EP3537541A1 - Electromagnetic decoupling - Google Patents

Abstract

The present invention relates to a device for transmitting and / or receiving radiofrequency signals comprising at least: • a microelectronic circuit • a first antenna (10) carried by a first zone of said microelectronic circuit • a second antenna (20) carried by a second zone of said microelectronic circuit; the device (1) comprises an electromagnetic decoupling module (30) of the first antenna (10) and the second antenna (20) carried by a third zone of said microelectronic circuit arranged between the first zone and the second zone; the electromagnetic decoupling module (30) comprising at least one raised structure and at least one connecting element of said raised structure to said microelectronic circuit.

Description

TECHNICAL FIELD OF THE INVENTION

The present invention generally relates to the field of antennas and more particularly that of miniature antennas used by all kinds of portable and mobile electronic devices for receiving and transmitting signals, typically in a range of frequencies currently up to about ten gigahertz ( GHz = 10 ⁹ Hertz), so that they can freely communicate within the limits of a geographical area covered by a so-called "wireless" or "wireless" network, a widely used English expression having the same meaning.

STATE OF THE ART

The so-called "wireless" communicating systems, which are increasingly used daily, and often almost permanently, by an ever-increasing user population, all have antennas for receiving and, more often than not, to transmit signals in the frequency band defined by the technical standard that governs them. It is mainly mobile phones, including those obeying the so-called GSM standard, the acronym for "global system for mobile communications" which defines a communication standard whose geographical coverage is worldwide.

Another communicating system, very widely used, which requires a very sensitive reception antenna, is the GPS acronym for "global positioning system". By decoding the signals coming from a satellite network, this system makes it possible to obtain, over the extent of the terrestrial globe, a very precise geographic positioning of the receiver. GPS receivers are increasingly present in mobile phones and all kinds of so-called smart phones or "smart phones" which also include all the functions of a personal digital assistant and the ability to connect to the global network of the Internet.

On the contrary, the wireless network can be designed to cover only a limited geographical area such as Wi-Fi, or even very restricted, such as the standard called "Bluetooth®" which allows communication up to ten meters of terminals between them.

Despite their necessary miniaturization to adapt to the dimensional constraints imposed by ever smaller sizes of housings, in particular thicknesses that have become very small, the antennas of the above devices must nevertheless be able to maintain optimum efficiency in the entire band of frequencies where they must operate. This efficiency depends on losses which are intrinsic to the antenna and which are measured most commonly using the so-called "S" parameters, of the English "scattering parameters" which make it possible to qualify the behavior of the antenna between the propagation medium on the one hand and the electronic control circuit on the other hand. In general terms, the S parameters have been designed and are used to measure and qualify the behavior of passive or active linear circuits operating in the frequency range referred to above often referred to as microwave or radio frequency (RF) in the technical literature. on these topics. They make it possible to evaluate the electrical properties of these circuits such as their gain, the loss of efficiency or the standing wave voltage ratio resulting from an impedance mismatch observed between the control circuit and the antenna. The adaptation of the antenna is defined in particular by the parameter S11 which represents the losses by reflection of the antenna. It is expressed in decibels (dB). The lower the value of S11, the better the adaptation and therefore the better the overall efficiency of the antenna.

The parameter S11, which is frequency dependent, makes it possible to define the bandwidth of the antenna, that is to say the frequency band in which S11 remains below a given threshold which is typically defined at a level of - 6dB. Under these conditions, a quarter of the power delivered by the electronic control circuit is lost by reflection and three quarters are therefore usefully radiated by the antenna.

The bandwidth of an antenna can be more or less wide. It is often expressed as a percentage of its center frequency. An antenna whose bandwidth is a few percent is considered to have a narrow band of operation. This type of antenna is well suited for certain applications. For example, for a GPS receiver, an antenna whose bandwidth is of the order of 2% is sufficient.

An antenna with a bandwidth equal to or greater than 15% is considered to have a wide bandwidth. Those whose bandwidth is greater than or equal to 20% benefit from a very wide bandwidth. Note that to qualify this type of antennas the acronym "UWB", the English "ultra wide band", is also often used.

The use of a very broadband antenna potentially offers many advantages. A single broadband antenna can then simultaneously cover several radio frequency standards. This makes it possible to reduce the number of antennas that must be able to be implemented in multiservice wireless devices such as smart phones, which gives not only a certain advantage in terms of cost but also allows to overcome technical problems that are difficult to solve otherwise, such as the parasitic coupling that can occur between the different antennas of the same smart phone.

However, faced with the versatility of UWB antennas, it is nonetheless sometimes necessary to have a second antenna, for example for communications according to the "Bluetooth®" protocol. Thus, even though the UWB antennas are used to restrict the number of antennas and thus the problems of electromagnetic coupling between two antennas close to each other, it appears that, in some cases of miniaturized devices, electromagnetic coupling problems remain between UWB antennas and other antennas present at the level of the microelectronic circuit carrying them.

The patent publication US 2014/085158 A1 discloses an antenna device with a part for decoupling between two antennas placed in a plane. This device may have different shapes, depending on the folding configuration of the metal element that constitutes it. The manufacturing methods of such a decoupling part are very rudimentary.

It is therefore an object of the invention to provide a solution to this problem of electromagnetic coupling by allowing the size reduction of antennas intended to be implanted in the same housing as their control circuit can however be done in preserving sufficient operating performance.

The present invention aims to solve at least in part the problems outlined above. Other objects, features and advantages of the present invention will become apparent from the following description and accompanying drawings. It is understood that other benefits may be incorporated.

SUMMARY OF THE INVENTION

• un circuit microélectronique s'étendant dans un plan principal d'extension et selon une direction principale d'extension ;
• une première antenne, de préférence à large bande, portée par une première zone dudit circuit microélectronique et s'étendant selon un premier plan d'extension, de préférence parallèle audit plan principal d'extension, de préférence disposée au regard d'une portion du circuit microélectronique ;
• une deuxième antenne portée par une deuxième zone dudit circuit microélectronique s'étendant selon un deuxième plan d'extension, de préférence parallèle audit premier plan d'extension ;

The present invention relates to a device for transmitting and / or receiving radiofrequency signals comprising at least:

• a microelectronic circuit extending in a main extension plane and in a main direction of extension;
• a first antenna, preferably broadband, carried by a first zone of said microelectronic circuit and extending in a first plane of extension, preferably parallel to said main extension plane, preferably arranged with respect to a portion of the microelectronic circuit;
• a second antenna carried by a second zone of said microelectronic circuit extending in a second extension plane, preferably parallel to said first extension plane;

Advantageously, the device is further characterized in that it further comprises an electromagnetic decoupling module of the first antenna and the second antenna, carried by a third zone of said microelectronic circuit arranged between the first zone and the second zone. , preferably the electromagnetic decoupling module being disposed between the first antenna and the second antenna;

Preferably, the electromagnetic decoupling module comprises at least one raised structure relative to said microelectronic circuit and at least one connecting element of said structure raised to said microelectronic circuit.

Compared to the decoupling technique implemented in the American anteriority US 2014/0085158 A1 supra. The structural and manufacturing methods of the device of the invention are significantly improved. In particular, the decoupling portion is raised relative to the main plane of the microelectronic circuit and is supported by an overmolding, a connecting element in the form of a plurality of vias passing through the overmolding so as to connect the decoupling part. elevated to the rest of the device, and advantageously to the mass. The provisions of the invention make it possible to use a deposition technique, in particular a metal deposition, to form the raised structure, offering great flexibility of shape, with a potentially very small thickness. However, the assembly is mechanically coherent and stronger than the prior art by the presence of the overmoulding element.

In one embodiment, the manufacture of the decoupling module can be widely shared with the manufacture of at least one of the antennas. Indeed, the overmoulding phase and, potentially, the polishing phase of the overmolding, can be pooled. Preferably, this common overmoulding then defines a single electrically conductive deposition plane for forming antenna portions of the decoupling portions.

The present invention makes it possible to have a device for transmitting and / or receiving radio frequency signals comprising two antennas having no or very little electromagnetic coupling with each other.

Indeed the present invention comprises an electromagnetic decoupling module between each of the first and second antennas of the device for transmitting and / or receiving radio frequency signals.

This electromagnetic decoupling module advantageously has an electrically conductive surface electrically connected by means of electrically conductive vias to the device for transmitting and / or receiving radio frequency signals.

In a particularly advantageous manner, this electromagnetic decoupling module is disposed between the first antenna and the second antenna. The use of an electrically conductive surface accompanied by a plurality of electrical conductive vias extending in a direction orthogonal to said electrical conductive surface makes it possible to reinforce the electromagnetic decoupling between the first and the second antenna. This makes it possible to form an electromagnetic shield comprising two parts, a first part consisting of the electrical conductive surface and a second part consisting of the plurality of electrical conductor vias.

The present invention also provides an electromagnetic decoupling module having an electrically conductive surface with respect to a portion of the microelectronic circuit and preferably raised relative to the microelectronic circuit by means of the vias electrically conductive. This allows a greater compactness of the device for transmitting and / or receiving radio frequency signals.

Advantageously, the use of electrical conducting vias for raising the elevated structure of the electromagnetic decoupling module provides a surface gain at the level of the microelectronic circuit which can be exploited to place microelectronic components, for example below the electromagnetic decoupling module. .

• Fourniture du circuit microélectronique présentant un plan principal d'extension ;
• Formation de la première antenne au niveau à la première zone dudit circuit microélectronique ;
• Formation de la deuxième antenne au niveau de la deuxième zone dudit circuit microélectronique ;
• Formation du dispositif de découplage électromagnétique au niveau de la troisième zone dudit circuit microélectronique, cette étape de formation comprenant au moins les étapes suivantes :
  1. i. Formation d'au moins un élément de raccordement au niveau de la troisième zone dudit du circuit microélectronique ;
  2. ii. Surmoulage du circuit microélectronique de manière à recouvrir en partie au moins l'au moins un élément de raccordement et le circuit microélectronique de sorte à définir une surface, de préférence plane, s'étendant sensiblement selon le troisième plan d'extension ;
  3. iii. Formation de la structure surélevée du module de découplage électromagnétique au niveau de ladite surface, de préférence par dépôt d'au moins un élément conducteur électrique.

The present invention also relates to a method of manufacturing a device for transmitting and / or receiving radio frequency signals according to the present invention.

• Providing the microelectronic circuit having a main extension plane;
• Forming the first antenna at the first zone of said microelectronic circuit;
• Forming the second antenna at the second zone of said microelectronic circuit;
• Formation of the electromagnetic decoupling device at the third zone of said microelectronic circuit, this forming step comprising at least the following steps:
  1. i. Forming at least one connecting element at the third zone of said microelectronic circuit;
  2. ii. Overmolding the microelectronic circuit so as to partially cover at least the at least one connecting element and the microelectronic circuit so as to define a surface, preferably plane, extending substantially along the third extension plane;
  3. iii. Formation of the raised structure of the electromagnetic decoupling module at said surface, preferably by deposition of at least one electrically conductive element.

BRIEF DESCRIPTION OF THE FIGURES

• La figure 1 illustre un dispositif d'émission et/ou de réception de signaux radiofréquences comprenant deux antennes distinctes présentant un couplage électromagnétique non souhaité, réduisant ainsi leurs performances respectives.
• Les figures 2a et 2b illustrent un dispositif d'émission et/ou de réception de signaux radiofréquences selon un mode de réalisation de la présente invention et comprenant un module de découplage électromagnétique.
• Les figure 3a, 3b, 3c, 3d et 3e illustrent des paramètres S d'un dispositif d'émission et/ou de réception de signaux radiofréquences comprenant deux antennes distinctes, en fonction des figures considérées le dispositif d'émission et/ou de réception de signaux radiofréquences comprend ou non un module de découplage électromagnétique selon un mode de réalisation de la présente invention.
  La figure 3a représente le coefficient de transmission inverse avec et sans module de découplage.
  La figure 3b représente le coefficient de réflexion de la première antenne sans le module de découplage.
  La figure 3c représente le coefficient de réflexion de la première antenne avec le module de découplage.
  La figure 3d représente le coefficient de réflexion de la deuxième antenne sans le module de découplage.
  La figure 3e représente le coefficient de réflexion de la deuxième antenne avec le module de découplage.
• Les figures 4a à 4e représentent différentes étapes d'un procédé de fabrication d'un élément antennaire surélevée selon un mode de réalisation de la présente invention.
• Les figures 5a à 5c représentent différentes étapes d'une technique de formation d'un via conducteur électrique vertical selon un mode de réalisation de la présente invention.
• La figure 6 représente un art antérieur d'une antenne UWB surélevée.

The objects, objects, as well as the features and advantages of the invention will become more apparent from the detailed description of an embodiment thereof which is illustrated by the following accompanying drawings in which:

• The figure 1 illustrates a device for transmitting and / or receiving radio frequency signals comprising two separate antennas having undesired electromagnetic coupling, thereby reducing their respective performances.
• The Figures 2a and 2b illustrate a device for transmitting and / or receiving radio frequency signals according to an embodiment of the present invention and comprising an electromagnetic decoupling module.
• The figure 3a , 3b , 3c , 3d and 3rd illustrate parameters S of a device for transmitting and / or receiving radio-frequency signals comprising two distinct antennas, according to the figures considered, the device for transmitting and / or receiving radio-frequency signals does or does not include an electromagnetic decoupling module according to an embodiment of the present invention.
  The figure 3a represents the inverse transmission coefficient with and without decoupling module.
  The figure 3b represents the reflection coefficient of the first antenna without the decoupling module.
  The figure 3c represents the reflection coefficient of the first antenna with the decoupling module.
  The figure 3d represents the reflection coefficient of the second antenna without the decoupling module.
  The figure 3e represents the reflection coefficient of the second antenna with the decoupling module.
• The Figures 4a to 4e represent different steps of a method of manufacturing a raised antennal element according to an embodiment of the present invention.
• The Figures 5a to 5c represent different steps of a technique of forming a vertical electrical conductor according to an embodiment of the present invention.
• The figure 6 represents a prior art of an elevated UWB antenna.

The accompanying drawings are given by way of example and are not limiting of the invention. These drawings are schematic representations and are not necessarily at the scale of the practical application.

DETAILED DESCRIPTION OF THE INVENTION

In the context of the present invention, two planes are considered parallel to each other, two planes having no coplanar deviation or having negligible deviation with respect to industrial tolerances, in particular less than 10 degrees and preferably less than 5 degrees.

In the present application, a broadband antenna, also called "UWB", means an antenna configured to operate in a frequency band ranging from a few megahertz to a few tens of gigahertz, for example between 3000 MHz and 11000 MHz. MHz.

• Avantageusement, ladite structure surélevée comprend au moins une surface conductrice électrique s'étendant selon un troisième plan d'extension coplanaire à au moins l'un parmi le premier plan d'extension et le deuxième plan d'extension.
  Cela permet d'accroître le découplage électromagnétique entre la première antenne et la deuxième antenne en diminuant le couplage électromagnétique entre la première antenne et la deuxième antenne, et de préférence en augmentant le couplage électromagnétique entre la surface conductrice électrique du module de découplage électromagnétique et l'une parmi la première antenne et la deuxième antenne.
• Avantageusement, l'élément de raccordement comprend une pluralité de vias conducteurs électriques électriquement connectés à ladite structure surélevée et audit circuit microélectronique et s'étendant depuis ladite structure surélevée vers ledit circuit microélectronique.
• Avantageusement, la surface conductrice électrique du module de découplage électromagnétique s'étend selon un troisième plan d'extension parallèle au plan principal d'extension.
  Cela permet d'accroître la compacité du dispositif tout en disposant d'un module découplage situé entre la première antenne et la deuxième antenne.
• Avantageusement, la pluralité de vias conducteurs électriques est disposée sur une partie au moins de la troisième zone du circuit microélectronique.
• Avantageusement, le premier plan d'extension et le deuxième plan d'extension sont décalés relativement à une direction perpendiculaire au premier plan d'extension et au deuxième plan d'extension.
  Cela permet de réduire le couplage électromagnétique entre la première antenne et la deuxième antenne tout en augmentant la compacité du dispositif.
• Avantageusement, au moins l'un parmi le premier plan d'extension et le deuxième plan d'extension sont coplanaires au plan principal d'extension. Cela permet de réaliser aisément la connexion électrique du circuit microélectronique avec l'une parmi la première antenne et la deuxième antenne.
• Avantageusement, le module de découplage électromagnétique est mécaniquement solidaire de la première antenne et de la deuxième antenne uniquement via le circuit microélectronique.
• Avantageusement, la structure surélevée du module de découplage électromagnétique est en partie au moins au-dessus d'une partie au moins des composants microélectroniques du circuit microélectronique, de préférence la structure surélevée du module de découplage électromagnétique recouvre au moins 15%, de préférence au moins 20% et avantageusement au moins 30% du circuit microélectronique.
• Avantageusement, la structure surélevée du module de découplage électromagnétique est en partie au moins au-dessus d'une partie au moins des composants microélectroniques du circuit microélectronique, de préférence la structure surélevée du module de découplage électromagnétique recouvre au moins 10%, de préférence au moins 20% et avantageusement au moins 30% du circuit microélectronique.
• Avantageusement, la structure surélevée du module de découplage électromagnétique présente au moins une extension transversale, perpendiculaire à ladite direction principale d'extension, supérieure ou égale à l'extension transversale, perpendiculaire à ladite direction principale d'extension, de la première surface conductrice électrique et à l'extension transversale, perpendiculaire à ladite direction principale d'extension, de la deuxième surface conductrice électrique.
• Avantageusement, la structure surélevée du module de découplage électromagnétique présente au moins une extension transversale perpendiculaire à ladite direction principale inférieure ou égale à la l'extension transversale dudit circuit microélectronique relativement à ladite direction principale d'extension.
• Avantageusement, le potentiel électrique de la structure surélevée du module de découplage électromagnétique est contrôlé, de préférence au travers dudit élément de raccordement.
  Le contrôle du potentiel électrique de la surface conductrice électrique permet un ajustement du découplage électromagnétique entre la première antenne et la deuxième antenne afin de l'améliorer et/ou de répondre à des conditions de fonctionnement ou des paramètres extérieurs.
• Avantageusement, le circuit microélectronique comprend une masse et la structure surélevée du module de découplage électromagnétique est électriquement connectée à ladite masse, de préférence au travers dudit élément de raccordement.
  Cela permet de réaliser un bouclier électromagnétique entre la première antenne et la deuxième antenne afin de limiter le couplage électromagnétique entre ces deux antennes.
• Avantageusement, la première antenne comprend une première surface conductrice électrique s'étendant selon le premier plan d'extension, la deuxième antenne comprend une deuxième surface conductrice électrique s'étendant selon le deuxième plan d'extension et la structure surélevée du module de découplage électromagnétique présente au moins une extension transversale, perpendiculaire à ladite direction principale d'extension, supérieure ou égale à l'extension transversale, perpendiculaire à ladite direction principale d'extension, de la première surface conductrice électrique et à l'extension transversale, perpendiculaire à ladite direction principale d'extension, de la deuxième surface conductrice électrique.
• Avantageusement, la première antenne comprend au moins une première structure surélevée relativement audit circuit microélectronique et au moins un premier élément de raccordement de ladite première structure surélevée audit circuit microélectronique, ladite première structure surélevée s'étendant dans le premier plan d'extension, le premier plan d'extension étant disposé en regard d'une partie au moins de ladite première zone dudit circuit microélectronique.
• Avantageusement, le premier élément de raccordement de ladite première structure surélevée audit circuit microélectronique comprend une première pluralité de vias conducteurs électriques électriquement connectés à ladite première structure surélevée et audit circuit microélectronique et s'étendant depuis ledit circuit microélectronique vers ladite première structure surélevée.
• Avantageusement, la première antenne est configurée pour fonctionner dans une bande de fréquences comprise entre 3000 MHz et 11000 MHz, et la deuxième antenne est configurée pour fonctionner dans une bande de fréquences comprise entre 2000 MHz et 3000 MHz.
• De préférence, la première antenne et la deuxième antenne sont configurées pour fonctionner dans des bandes de fréquences distinctes, de préférence séparée l'une de l'autre.
• Avantageusement, la première antenne est configurée pour fonctionner à une fréquence comprise entre 3000 MHz et 11000 MHz, et la deuxième antenne est configurée pour fonctionner dans une bande de fréquences comprise entre 2200 MHz et 2600 MHz, de préférence entre 2300 MHz et 2500 MHz et avantageusement entre 2400 MHz et 2 483.5 MHz.
  Cela permet de disposer d'une antenne à large bande ainsi que d'une antenne de type Bluetooth® afin d'accroître les fonctionnalités du dispositif d'émission et/ou de réception de signaux radiofréquences tout en conservant une compacité réduite et tout en limitant, voire évitant, le couplage électromagnétique entre ces deux antennes.
• Avantageusement, la structure surélevée du module de découplage électromagnétique présente une aire comprise entre 15% et 75%, avantageusement entre 25% et 50% de l'aire de l'une parmi la surface de la première antenne dans le premier plan d'extension et la surface de la deuxième antenne dans le deuxième plan d'extension.
  Cela permet d'améliorer le découplage électromagnétique entre la première antenne et la deuxième antenne.
• Avantageusement, la structure surélevée présente une forme identique à au moins une forme d'au moins l'une parmi la première antenne et la deuxième antenne.
  Cela permet d'améliorer le découplage électromagnétique entre la première antenne et la deuxième antenne.
• Avantageusement, le rapport entre l'aire de la surface conductrice électrique du module de découplage électromagnétique et l'aire de la surface du circuit microélectronique s'étendant dans le plan principale d'extension est compris entre 10% et 50%, de préférence entre 20% et 40% et avantageusement entre 25% et 35%.
  Cela permet d'améliorer le découplage électromagnétique entre la première antenne et la deuxième antenne.
• Avantageusement, le rapport entre l'aire de la surface conductrice électrique du module de découplage électromagnétique et l'aire de la surface de la première antenne dans le premier plan d'extension est compris entre 50% et 100%, de préférence entre 70% et 90% et avantageusement entre 75% et 85%.
  Cela permet d'améliorer le découplage électromagnétique entre la première antenne et la deuxième antenne.
• Avantageusement, le rapport entre l'aire de la surface conductrice électrique du module de découplage électromagnétique et l'aire de la surface de la deuxième antenne dans le deuxième plan d'extension est compris entre 50% et 100%, de préférence entre 70% et 90% et avantageusement entre 75% et 85%.
  Cela permet d'améliorer le découplage électromagnétique entre la première antenne et la deuxième antenne.
• Avantageusement, l'étape de formation de la structure surélevée du module de découplage électromagnétique est réalisée par dépôt d'au moins un élément conducteur électrique, de préférence par pulvérisation sélective de plasma.
• Avantageusement, l'étape de formation de l'au moins un élément de raccordement comprend la formation d'une pluralité de vias conducteurs électriques.
• Avantageusement, l'étape de formation d'au moins un élément de raccordement au niveau de la troisième zone dudit du circuit microélectronique comprend au moins les étapes suivantes :
  • ∘ Soudure d'une extrémité d'au moins un fil conducteur électrique au niveau d'une partie de la troisième zone dudit circuit microélectronique ;
  • ∘ Coupure d'une partie au moins dudit fil conducteur électrique soudé au niveau d'une partie de la troisième zone dudit circuit microélectronique ;
  • ∘ Disposition dudit fil conducteur électrique soudé au niveau d'une partie de la troisième zone dudit circuit microélectronique de sorte à ce qu'il présente une direction d'extension orthogonale au plan principal d'extension dudit circuit microélectronique.
• Avantageusement, l'étape de formation de la première antenne comprend au moins les étapes suivantes :
  • ∘ Former une première pluralité de vias conducteurs électriques au niveau de la première zone du circuit microélectronique ;
  • ∘ Surmouler le circuit microélectronique de manière à recouvrir en partie au moins lesdits vias conducteurs électriques de la première pluralité de vias conducteurs électriques de sorte à définir une première surface, de préférence plane, s'étendant sensiblement selon le premier plan d'extension ;
  • ∘ Former une première surface conductrice électrique de la première antenne au niveau de ladite première surface, de préférence par dépôt d'au moins un élément conducteur électrique.
  • ∘ De préférence, mais non limitativement, on protège la première surface conductrice électrique par un film isolant électrique, par exemple par un masque isolant électrique relativement fin par rapport à l'épaisseur de la première surface conductrice électrique et généralement dénommé « vernis de protection ».
• Selon un mode de réalisation, l'étape de formation de la première antenne comprend au moins les étapes suivantes :
  • ∘ Fourniture d'un circuit microélectronique ;
  • ∘ Formation d'une première pluralité de pistes conductrices électriques au niveau de la première zone du circuit microélectronique ;
  • ∘ Formation d'une troisième pluralité de vias conducteurs électriques au niveau de ladite première zone du circuit microélectronique ;
  • ∘ Surmoulage du circuit microélectronique de manière à recouvrir en partie au moins lesdits vias conducteurs électriques de la troisième pluralité de vias conducteurs électriques de sorte à définir une première surface, de préférence plane, s'étendant sensiblement selon le premier plan d'extension.
  • ∘ Formation d'une deuxième pluralité de pistes conductrices électriques au niveau de ladite première surface, de préférence par dépôt d'au moins un élément conducteur électrique.
• Avantageusement, l'étape de formation du module de découplage électromagnétique est réalisée en même temps que l'étape de formation de la première antenne.

Before starting a detailed review of embodiments of the invention, are set forth below optional features that may optionally be used in combination or alternatively:

• Advantageously, said raised structure comprises at least one electrical conductive surface extending along a third extension plane coplanar with at least one of the first extension plane and the second extension plane.
  This makes it possible to increase the electromagnetic decoupling between the first antenna and the second antenna by decreasing the electromagnetic coupling between the first antenna and the second antenna, and preferably by increasing the electromagnetic coupling between the electrically conductive surface of the electromagnetic decoupling module and the electromagnetic coupling. one of the first antenna and the second antenna.
• Advantageously, the connecting element comprises a plurality of electrical conductor vias electrically connected to said raised structure and said microelectronic circuit and extending from said raised structure to said microelectronic circuit.
• Advantageously, the electrically conductive surface of the electromagnetic decoupling module extends along a third extension plane parallel to the main extension plane.
  This increases the compactness of the device while having a decoupling module located between the first antenna and the second antenna.
• Advantageously, the plurality of electrical conductor vias is disposed on at least part of the third zone of the microelectronic circuit.
• Advantageously, the first extension plane and the second extension plane are offset relative to a direction perpendicular to the first extension plane and the second extension plane.
  This reduces the electromagnetic coupling between the first antenna and the second antenna while increasing the compactness of the device.
• Advantageously, at least one of the first extension plane and the second extension plane are coplanar with the main extension plane. This makes it easy to make the electrical connection of the microelectronic circuit with one of the first antenna and the second antenna.
• Advantageously, the electromagnetic decoupling module is mechanically secured to the first antenna and the second antenna only via the microelectronic circuit.
• Advantageously, the elevated structure of the electromagnetic decoupling module is partly at least over at least a portion of the microelectronic components of the microelectronic circuit, preferably the raised structure of the electromagnetic decoupling module covers at least 15%, preferably at least minus 20% and advantageously at least 30% of the microelectronic circuit.
• Advantageously, the raised structure of the electromagnetic decoupling module is partly at least over at least a portion of the microelectronic components of the microelectronic circuit, preferably the raised structure of the electromagnetic decoupling module covers at least 10%, preferably at least minus 20% and advantageously at least 30% of the microelectronic circuit.
• Advantageously, the raised structure of the electromagnetic decoupling module has at least one transverse extension, perpendicular to said main extension direction, greater than or equal to the transverse extension, perpendicular to said main extension direction, of the first electrically conductive surface. and at the transverse extension, perpendicular to said main extension direction, of the second electrical conductive surface.
• Advantageously, the raised structure of the electromagnetic decoupling module has at least one transverse extension perpendicular to said main direction less than or equal to the transverse extension of said microelectronic circuit relative to said main direction of extension.
• Advantageously, the electrical potential of the raised structure of the electromagnetic decoupling module is controlled, preferably through said connecting element.
  Controlling the electrical potential of the electrical conducting surface allows adjustment of the electromagnetic decoupling between the first antenna and the second antenna to improve it and / or to respond to operating conditions or external parameters.
• Advantageously, the microelectronic circuit comprises a mass and the raised structure of the electromagnetic decoupling module is electrically connected to said mass, preferably through said connecting element.
  This allows for an electromagnetic shield between the first antenna and the second antenna to limit the electromagnetic coupling between these two antennas.
• Advantageously, the first antenna comprises a first electrical conductive surface extending along the first extension plane, the second antenna comprises a second electrical conductive surface extending along the second extension plane and the elevated structure of the electromagnetic decoupling module. has at least one transverse extension, perpendicular to the said principal extension direction, greater than or equal to the transverse extension, perpendicular to the said principal extension direction, of the first electrical conducting surface and to the transverse extension, perpendicular to the said main direction of extension, the second electrical conductive surface.
• Advantageously, the first antenna comprises at least a first raised structure relative to said microelectronic circuit and at least a first connecting element of said first structure raised to said microelectronic circuit, said first raised structure extending in the first extension plane, the first extension plane being disposed facing at least a portion of said first zone of said microelectronic circuit.
• Advantageously, the first connecting element of said first structure raised to said microelectronic circuit comprises a first plurality of electrical conductor vias electrically connected to said first raised structure and to said microelectronic circuit and extending from said microelectronic circuit to said first raised structure.
• Advantageously, the first antenna is configured to operate in a frequency band between 3000 MHz and 11000 MHz, and the second antenna is configured to operate in a frequency band between 2000 MHz and 3000 MHz.
• Preferably, the first antenna and the second antenna are configured to operate in separate frequency bands, preferably separated from each other.
• Advantageously, the first antenna is configured to operate at a frequency between 3000 MHz and 11000 MHz, and the second antenna is configured to operate in a frequency band between 2200 MHz and 2600 MHz, preferably between 2300 MHz and 2500 MHz and advantageously between 2400 MHz and 2483.5 MHz.
  This makes it possible to have a broadband antenna as well as a Bluetooth® type antenna in order to increase the functionality of the device for transmitting and / or receiving radio frequency signals while maintaining a reduced compactness and while limiting or even avoiding the electromagnetic coupling between these two antennas.
• Advantageously, the elevated structure of the electromagnetic decoupling module has an area of between 15% and 75%, advantageously between 25% and 50% of the area of one of the surface of the first antenna in the first extension plane. and the surface of the second antenna in the second extension plane.
  This improves the electromagnetic decoupling between the first antenna and the second antenna.
• Advantageously, the raised structure has a shape identical to at least one form of at least one of the first antenna and the second antenna.
  This improves the electromagnetic decoupling between the first antenna and the second antenna.
• Advantageously, the ratio between the area of the electrically conductive surface of the electromagnetic decoupling module and the surface area of the microelectronic circuit extending in the main plane of extension is between 10% and 50%, preferably between 20% and 40% and advantageously between 25% and 35%.
  This improves the electromagnetic decoupling between the first antenna and the second antenna.
• Advantageously, the ratio between the area of the electrically conductive surface of the electromagnetic decoupling module and the area of the surface of the first antenna in the first extension plane is between 50% and 100%, preferably between 70%. and 90% and advantageously between 75% and 85%.
  This improves the electromagnetic decoupling between the first antenna and the second antenna.
• Advantageously, the ratio between the area of the electrically conductive surface of the electromagnetic decoupling module and the area of the surface of the second antenna in the second extension plane is between 50% and 100%, preferably between 70%. and 90% and advantageously between 75% and 85%.
  This improves the electromagnetic decoupling between the first antenna and the second antenna.
• Advantageously, the step of forming the raised structure of the electromagnetic decoupling module is performed by deposition of at least one electrically conductive element, preferably by selective spraying of plasma.
• Advantageously, the step of forming the at least one connecting element comprises forming a plurality of electrical conductor vias.
• Advantageously, the step of forming at least one connecting element at the third zone of said microelectronic circuit comprises at least the following steps:
  • ∘ Welding an end of at least one electrical conductor wire at a portion of the third zone of said microelectronic circuit;
  • ∘ Cutting at least a portion of said soldered electrical conductor wire at a portion of the third zone of said microelectronic circuit;
  • ∘ Providing said soldered electrical conductor wire at a portion of the third zone of said microelectronic circuit so that it has an extension direction orthogonal to the main extension plane of said microelectronic circuit.
• Advantageously, the step of forming the first antenna comprises at least the following steps:
  • Forming a first plurality of electrical conductor vias at the first zone of the microelectronic circuit;
  • Over-molding the microelectronic circuit so as to cover at least part of said electrical conductor vias of the first plurality of electrical conductor vias so as to define a first surface, preferably flat, extending substantially in the first extension plane;
  • ∘ Form a first electrically conductive surface of the first antenna at said first surface, preferably by deposition of at least one electrically conductive element.
  • Preferably, but not exclusively, the first electrically conductive surface is protected by an electrical insulating film, for example by a relatively thin electrical insulating mask with respect to the thickness of the first electrically conductive surface and generally referred to as "protective varnish". .
• According to one embodiment, the step of forming the first antenna comprises at least the following steps:
  • ∘ Providing a microelectronic circuit;
  • Forming a first plurality of electrical conductive tracks at the first zone of the microelectronic circuit;
  • ∘ forming a third plurality of electrical conductor vias at said first zone of the microelectronic circuit;
  • Over-molding of the microelectronic circuit so as to partially cover at least said electrical conductor vias of the third plurality of electrical conductor vias so as to define a first surface, preferably plane, extending substantially in the first plane of extension.
  • ∘ Formation of a second plurality of electrical conductive tracks at said first surface, preferably by deposition of at least one electrically conductive element.
• Advantageously, the step of forming the electromagnetic decoupling module is performed at the same time as the step of forming the first antenna.

The present invention finds the preferred field of application antennas boxed or AIP, acronym for the English "antenna in package". This field covers all the solutions that make it possible to implement in one and the same device: the radiofrequency chip for transmitting and receiving the radiofrequency signals; the antenna or antennas and their matching networks as well as other radio frequency components.

For this type of device, one of the main requirements is efficiency combined with compactness. The present invention as presented later, allows to meet both of these requirements.

Technique possible pour la réalisation d'un élément antennaire surélevé :We will first describe a method of manufacturing an elevated antenna using vertical vias formed by a technique called the "Bond Via Array" technique.

Possible technique for the realization of a raised antennal element :

The present invention rests in part at least on a manufacturing technique which surprisingly happens to be in perfect adequacy with the requirements required by this technical field. In general, vias are manufactured to form conductive elements between a raised portion above the substrate and the surface thereof.

Thus, according to a preferred embodiment, the present invention advantageously takes advantage of the Bond Via Array (BVA ™) technique (see in particular the article "BVA: Molded Cu Wire Contact Solution for Very High Density Package-on-Package ( PoP) Applications, Vern Solberg and Ilyas Mohammed Invensas Corporation, 02/06/2013) which allows the construction of connected vias on a circuit microelectronics extending perpendicular to the extension plane of the microelectronic circuit.

We will now describe the steps of a method in this context for forming one or more elevated antennas with respect to a microelectronic circuit according to a preferred embodiment of the present invention.

• Fourniture d'un circuit microélectronique 2 ;
  Ce circuit microélectronique peut comprendre des composants microélectroniques, des pistes mais également un plan de masse.
• Formation d'un ou d'une pluralité d'éléments de raccordement mécanique et électrique d'au moins un élément antennaire à former ;
  De manière préférée, cette pluralité d'éléments de raccordement comprend une pluralité de vias conducteurs électriques 12, 32.
  Cette étape de formation peut nécessiter le masquage d'une partie au moins du circuit microélectronique 2 de sorte à ce que l'intégralité du circuit microélectronique ne soit pas exposée aux étapes que peut comprendre la formation des éléments de raccordement.
• Surmoulage d'une partie au moins du circuit microélectronique 2 de manière à recouvrir en partie au moins lesdits éléments de raccordement.
  Selon un mode de réalisation, le circuit microélectronique 2 est surmoulé d'un matériau polymère, par exemple une résine.
• De manière optionnelle, réalisation d'un polissage du surmoulage, via une étape de CMP (de l'anglais « chemical mechanical polishing ») par exemple, de sorte à définir au moins une surface s'étendant sensiblement selon un plan d'extension et de sorte à exposer une partie desdits éléments de raccordement 12, 32 ;
• Formation d'une ou de plusieurs surfaces conductrices électriques au niveau de ladite surface, de préférence par dépôt d'au moins un élément conducteur électrique.
  Pour cette étape, un masquage d'une partie de ladite surface peut être nécessaire afin de ne pas réaliser la ou les surfaces conductrices électriques sur l'ensemble de ladite surface, ou bien afin de réaliser une surface conductrice électrique présentant une géométrie particulière, comme par exemple des pistes ou bien des structures polygonales complexes.
• Optionnellement, retrait du surmoulage.

This method can thus comprise at least the following steps:

• Providing a microelectronic circuit 2;
  This microelectronic circuit may comprise microelectronic components, tracks but also a ground plane.
• Formation of one or a plurality of mechanical and electrical connection elements of at least one antenna element to be formed;
  Preferably, this plurality of connection elements comprises a plurality of electrical conductive vias 12, 32.
  This forming step may require the masking of at least a portion of the microelectronic circuit 2 so that the entire microelectronic circuit is not exposed to the steps that can comprise the formation of the connecting elements.
• Overmolding at least a portion of the microelectronic circuit 2 so as to partially cover at least said connecting elements.
  According to one embodiment, the microelectronic circuit 2 is overmolded with a polymer material, for example a resin.
• Optionally, carrying out a polishing of the overmoulding, via a CMP (chemical mechanical polishing) step for example, so as to define at least one surface extending substantially along an extension plane and so as to expose a portion of said connecting members 12, 32;
• Formation of one or more electrically conductive surfaces at said surface, preferably by deposition of at least one electrically conductive element.
  For this step, a masking of a portion of said surface may be necessary in order not to make the electrically conductive surface (s) on the whole of said surface, or in order to produce an electrically conductive surface having a particular geometry, such as for example tracks or complex polygonal structures.
• Optionally, removal of overmolding.

In order to illustrate this manufacturing process, Figures 4a to 4e will now be described.
The figure 4a represents a microelectronic circuit 2 according to a sectional view. This microelectronic circuit 2 comprises a substrate 3 and a plurality of microelectronic components 4.

The figure 4b illustrates the formation of the mechanical and electrical connection elements 12, 32. These connecting elements are electrical conductive vias 12, 32.

Advantageously, the connecting elements are conducting wires. They are preferably formed from an electrically conductive micro-wire advantageously welded to a part of the microelectronic circuit 2 and then straightened in a vertical position, that is to say in a direction orthogonal to the main extension plane of the substrate 3.

According to one embodiment, the electrical conducting vias 12, 32 have a diameter, according to their transverse dimension, of between 10 .mu.m and 500 .mu.m, preferably between 20 .mu.m and 250 .mu.m and advantageously equal to 50 .mu.m.

Advantageously, the spacing between two electrical conductive vias 12, 32 is between 150 μm and 500 μm, preferably between 300 μm and 3000 μm and advantageously between 250 μm and 1000 μm.

Advantageously, the height dimension of the conductive vias 12, 32 is between 100 μm and 5000 μm, preferably between 750 μm and 3000 μm and advantageously equal to 1500 μm.

Preferably, the electrical conducting vias 12, 32 comprise at least one electrically conductive material is taken from at least: copper, gold, silver, aluminum, or an alloy formed by all or part of these elements.

The connection elements then form electrical conducting vias 12, 32 extending from the substrate 3 in a direction orthogonal to the main extension plane of the substrate 3.

This step of forming the electrical conducting vias 12, 32 will be described in greater detail below through Figures 5a to 5c .

Each via electrical conductor 12, 32 has a proximal end 12a, 32a integral with the substrate 3 and a distal end 12b, 32b intended to be secured to at least one metallized surface to be formed.

The figure 4c represents the overmolding step of the microelectronic circuit 2. This overmoulding is advantageously made from one or more resin-type polymers commonly used in microelectronics.

According to a non-illustrated embodiment, this resin 5 is deposited in a height dimension smaller than the height dimension of the connecting elements 12, 32.

According to a preferred embodiment and presented in figure 4c , overmolding is carried out so that the resin 5 covers the connecting elements 12, 32, that is to say that the resin 5 used for overmolding is preferably deposited in a height dimension greater than the dimension in height of the connecting elements 12, 32. According to this embodiment, the distal end 12b, 32b of the electrical conductive vias 12, 32 is then embedded in the resin 5.

Advantageously, the height dimension of the resin 5 is between 100 μm and 5000 μm, preferably between 750 μm and 3000 μm and advantageously equal to 1500 μm.

It will be understood that the use of an overmolding technique, in particular with a resin, makes it possible to take advantage of a liquid phase for placing the overmolding element in the appropriate places and surrounding the vias, and then, after solidification of the overmoulding material (typically by polymerization of the resin) to have a solid element in effect to build the portions of the upper plane of overmolding, in particular by a deposition of conductive material.

According to this embodiment, illustrated in figure 4d , a CMP type chemical mechanical polishing step may be necessary to reduce the height dimension of the resin at least up to the height dimension of the connecting members 12, 32 to expose at least the end distal 12b, 32b electrical conductive vias 12, 32.

In a clever way, this polishing step makes it possible, on the one hand, to define a raised flat surface relative to the microelectronic circuit 2 and, on the other hand, to expose the connection elements 12, 32, and preferably by locally spreading the distal end. 12b, 32b electrical conducting vias 12, 32 relative to said flat surface. This spreading phenomenon comes from the polishing of the distal end 12b, 32b of the connecting elements 12, 32. As will be seen later, this local spreading of the material of which the connection elements 12, 32 are composed participates in the mechanical and mainly electrical connection of the electrical conducting vias 12, 32 with the electrical conductive surface (s) to be formed.

The figure 4e represents the formation of two electric conductive surfaces 11, 31. The formation of each of these electric conductive surfaces 11, 31 comprises at least the deposition of at least one electrically conductive material.

According to one embodiment, this deposit may be a deposit by selective plasma spraying, for example, or by any other type of deposit allowing the formation of said electric conductive surfaces.

In a particularly advantageous manner, the deposition technique used is configured to allow the electrical connection between the distal end 12b, 32b of the electrical conductive vias 12, 32 and the deposited electrical conductive material.

Preferably, the deposited electrical conductive material is taken from at least: copper, nickel, gold, silver, aluminum, palladium or an alloy formed by all or part of these elements.

According to a preferred embodiment, the two electric conductive surfaces 11, 31 are formed at the same time and preferably from the same deposit of one or more electrically conductive materials. In addition, a mask can be used to form from the same deposit two electric conductive surfaces 11, 31 disjoint, that is to say not integral with each other in their respective extension plane .

Advantageously, one or more masks may be used to form one or more electrically conductive surfaces 11, 31 which are distinct from one another and / or which have particular geometries, such as tracks, discs, circles, etc. ...

We will now describe more precisely, according to one embodiment, the step of forming one or a plurality of mechanical and electrical connection elements through the Figures 5a to 5b .

The figure 5a represents a substrate 3 comprising an electrical conductive zone 62 and an electrical non-conductive zone 63.

By means of a wiring tool 60, an electrical conductor wire 61 is welded at the electrically conductive area 61 as illustrated in FIG. figure 5a .

Then the wiring tool 60 unwinds a portion of the electrical conductor wire 61 before cutting it at the electrical non-conductive area 62 as illustrated in FIG. figure 5b . These previous steps are common when microstrain is performed by the ultrasound wiring technique also called "wire bonding" in English.

Finally, by means of the same tool or of another, the electrical conductor wire 61 cut is disposed in a position orthogonal to the main plane of the substrate 3 so as to define an electrical conductive via 12, as illustrated in FIG. figure 5c .

As will be presented hereinafter, the present invention advantageously takes advantage of the BVA ™ construction technique to, on the one hand, increase the compactness of the device for transmitting and / or receiving radio frequency signals and, on the other hand, to reduce the number of steps in the manufacturing process.

This manufacturing method also allows a better dimensional accuracy in the production of electrical conductive surfaces which is an essential factor in the operation of the electromagnetic elements since the resonance frequencies and the electromagnetic couplings are directly affected by the dimensional aspect of the electromagnetic elements. electromagnetic elements.

In addition, this allows a great flexibility in the design of the antennas element (s), in particular the possibility of placing one or more antennas in one or more optimal positions relative to their functions.

This also allows a better reproducibility of the characteristics which represents a certain advantage in mass production.

Exemple d'antenne à large bande passante (UWB) :Finally, this method is compatible with electronic mass production processes, it has the advantage of being integrable in the assembly flow and industrial packaging therefore the cost is significantly reduced and reliability increased.

Example of a broadband antenna (UWB) :

With regard to the dual problem of compactness and efficiency, we will now describe a high bandwidth antenna, called "UWB", elevated and its manufacturing process using the technique of vias formation previously introduced.

For the question of compactness, we know for example devices according to the figure 6 which comprise a UWB type antenna raised relative to the microelectronic circuit 2 in order to increase the compactness of the device. Nevertheless, this type of solution still presents problems of compactness and efficiency.

Indeed, this type of device has a first disadvantage with respect to the efficiency of this UWB antenna 10. Due to its electrical connection with the microelectronic circuit 2 only at the flanks 11e carriers of the antenna UWB 10, there remain parts of the UWB antenna 10 relatively electrically distant microelectronic circuit 2, involving an increase in the electrical resistance of the antenna UWB 10 in some places.

In addition, the flanks 11e carriers of the UWB antenna 10 occupy a significant space on the microelectronic circuit 2 involving significant design constraints.

The present invention proposes a method of manufacturing a raised UWB type antenna solving at least in part these disadvantages and making it possible to meet at least partly the dual problem of efficiency and compactness.

According to one aspect, the present invention therefore relates to the realization of a broadband antenna called "UWB" elevated relative to a microelectronic circuit.

Advantageously taking advantage of the BVA ™ technique previously introduced, the present invention allows the formation of a UWB antenna over a microelectronic circuit so as to reduce the size that this type of antenna can represent and so to increase its efficiency via a greater distribution of mechanical and electrical connections of said UWB antenna with the microelectronic circuit.

Thus, according to a preferred embodiment, the present invention relates to a device for transmitting and / or receiving radio frequency signals comprising at least one microelectronic circuit extending in a main extension plane and in a main direction of extension. .

Advantageously, this radiofrequency transmission and / or reception device is further characterized in that it comprises a first antenna, preferably a UWB type broadband antenna, carried by a first zone of said microelectronic circuit and extending in a first extension plane, preferably parallel to said main extension plane and preferably disposed facing a portion of the microelectronic circuit.

Preferably, the first antenna comprises at least a first raised structure relative to said microelectronic circuit and at least a first connecting element of said structure raised to said microelectronic circuit.

We will now describe, through the figure 1 , a device for transmitting and / or receiving radio frequency signals comprising a first antenna 10 of the UWB type.

This radiofrequency transmission and / or reception device has traditionally a microelectronic circuit 2 arranged on a substrate 3 and comprising a plurality of microelectronic components 4. This microelectronic circuit 2 extends along a main extension plane and has a main extension dimension in a main direction.

The first antenna 10, for example of UWB type, has a first electrically conductive surface 11 raised by means of a first plurality of electrical conductive vias 12 electrically connecting this first electrically conductive surface 11 to the microelectronic circuit 2 and disposed above a first zone of the microelectronic circuit 2. This first electrically conductive surface 11 extends in a first plane of extension preferably parallel to the main plane of extension of the microelectronic circuit 2.

According to one embodiment, the first zone represents at least 25%, preferably at least 50% and advantageously at least 65% of the surface of the microelectronic circuit 2.

Advantageously, the first plurality of electrical conductive vias 12 is disposed mainly on a part of the periphery of the microelectronic circuit 2 and in particular mainly on one side of the microelectronic circuit 2.

According to one embodiment, the first plurality of electrical conductor vias 12 may be disposed at a distance from the periphery of the microelectronic circuit 2, for example in an internal zone of the microelectronic circuit 2, that is to say at the level of microelectronic components. 4, for example between microelectronic components 4.

This can make it possible to bring the electrical conducting vias 12 closer to certain parts of the microelectronic circuit 2, for example to certain microelectronic components 4 in particular. This may also make it possible to optimize the lengths of radiofrequency paths, in other words to optimize the distance between the antenna element and the part of the microelectronic circuit 2 intended to process the radio frequency signal or signals.

Advantageously, the number of electrical conducting vias of the first plurality of electrical conductor vias 12 is between 4 and 80, preferably between 8 and 40 and advantageously between 12 and 20.

It should be noted that in this figure the first plurality of electrical conductor vias 12 may comprise electrical conductive vias 12 grouped in several groups so for example to electrically connect certain portions of the first electrical conductive surface 11 at different points of the microelectronic circuit 2 .

Advantageously, the spacing between two groups of electrical conductive vias 12 is between 150 .mu.m and 50000 .mu.m, preferably between 200 .mu.m and 10000 .mu.m and advantageously between 250 .mu.m and 3000 .mu.m.

According to one embodiment, the number of electrical conducting vias of the first plurality of electrical conductor vias 12 is greater at one side of the first antenna 10.

According to one embodiment, the first antenna 10 comprises at least one electrical conductor via the first plurality of electrical conductor vias 12 at each corner of its geometric shape.

Without limitation, but as illustrated in figure 1 , the first antenna 10 can be arranged cantilevered, that is to say not be carried by a plurality of electrical conductive vias 12 at one or two contiguous sides. Thus, in this figure, the first antenna 10 is secured to the microelectronic circuit 2 at two contiguous sides, thus providing it cantilevered. This is particularly useful when the microelectronic component (s) 4 located under the first electrical conductive surface (11) prevent the provision of electrical conductor vias (12), or when the dimensions of the first electrical conducting surface (11) are such that one or more microelectronic components (4) make impossible the provision of additional electrical conductors vias 12.

Advantageously, this cantilevered arrangement allows a distribution of the planar currents, for example as in an antennal element of the PIFA type, that is to say a planar antennal device called "inverted F".

In this figure, and according to one embodiment, it will be noted that the first electrical conductive surface 11 has a first portion 11a and a second portion 11b mechanically and electrically connected to each other via a third portion 11c so as to define a slot 11d. Preferably, the second portion 11b has a lower surface than the first portion 11a, and a transverse extension, perpendicular to the main direction of extension of the microelectronic circuit 2, greater than that of the first portion 11a.

The presence of the first 11a and the second 11b portions having distinct geometries and forming the first electrical conductive surface 11 allows the first antenna 10 to have several resonance frequencies.

Indeed, it should be noted that the resonance frequencies of the different modes governing an antenna depend on the dimensions (width and length) of the latter and / or its different parts.

Thus, the production of this first cantilevered antenna 10 allows a precise and easy adjustment of the dimensions of the first electrically conductive surface 11 and therefore the resonant frequencies of said first antenna 10, preferably without regard to the mechanical rigidity of the first antenna 10 since the first electrical conductive surface 11 is supported by overmolding, that is to say by the resin 5.

In addition, the electromagnetic coupling between the resonance modes of the same antenna characterizes the bandwidth thereof. As a result, the geometry of the antenna directly influences its electromagnetic characteristics.

As a result, the electromagnetic coupling between the different resonance modes of the first antenna 10 varies according to the width of the slot 11d separating the first 11a and second 11b portions of the first electrical conducting surface 11.

In particular, the narrower the slot 11d, the greater the electromagnetic coupling between the first portion 11a and the second portion 11b, which may be particularly advantageous in certain applications.

According to one embodiment, the slit 11d has a width dimension of between a few tens of micrometers and a few hundred micrometers, and preferably of the order of 100 microns.

Advantageously, the slot 11d has a width dimension of between 1 .mu.m and 1000 .mu.m, preferably between 25 .mu.m and 500 .mu.m and advantageously between 50 .mu.m and 150 .mu.m.

In comparison with the techniques of the state of the art, the present invention makes it possible to create one or more slots 11d of controlled width. Indeed, it is the process of forming the first electrically conductive surface 11 by physico-chemical deposition that achieves this control and accuracy.

According to this embodiment, a first group of electrical conductive vias 12 mechanically and electrically connects the first portion 11a of the first electrical conductive surface 11 to the microelectronic circuit 2, and a second group of electrical conductive vias 12 mechanically and electrically connects the second portion. 11b of the first electrically conductive surface 11 to the microelectronic circuit 2.

It should be noted that here again the use of electric conductor vias 12 makes it possible to improve the performance of the first antenna 11 by electrically connecting each of the first 11a and second 11b portions of the first electrical conductive surface 11 to the microelectronic circuit 2.

As illustrated in figure 1 the first electrical conductive surface 11 covers at least 25%, preferably at least 50% and advantageously at least 65% of the microelectronic circuit 2.

As previously indicated, the present invention finds the preferred field of application antennas in a box or AIP, acronym for the English "antenna in package", and this area is facing problems of efficiency and compactness.

Thus, in order to solve this problem, the present invention advantageously takes advantage of the vias formation technique previously presented. Indeed, this technique allows the realization of the first antenna 10 raised above the microelectronic circuit. This advantageous arrangement allows a significant gain in compactness. As for the efficiency, this manufacturing method allows a very good reproducibility of the characteristics of the first antenna, a criterion necessary for the mass production of this type of device.

• Fourniture d'un circuit microélectronique 2 ;
• Formation d'une première pluralité de vias conducteurs électriques 12 destinée à raccorder mécaniquement et électriquement la première antenne 10 au niveau d'une première zone du circuit microélectronique 2 ;
• Surmoulage du circuit microélectronique 2 de manière à recouvrir en partie au moins lesdits vias conducteurs électriques de la première pluralité de vias conducteurs électriques 12.
• Réalisation d'un polissage du surmoulage via une étape de CMP de sorte à définir une première surface s'étendant sensiblement selon le premier plan d'extension et de sorte à exposer la première pluralité de vias conducteurs électriques 12 au niveau de ladite première surface ;
• Formation de la première surface conductrice électrique 11 de la première antenne 10 au niveau de ladite première surface, de préférence par dépôt d'au moins un élément conducteur électrique.

As regards the manufacturing method of this elevated UWB antenna, the method described above can be adapted as follows:
This method may comprise at least the following steps:

• Providing a microelectronic circuit 2;
• Forming a first plurality of electrically conductive vias 12 for mechanically and electrically connecting the first antenna 10 at a first zone of the microelectronic circuit 2;
• Over-molding of the microelectronic circuit 2 so as to partially cover at least said electrical conductor vias of the first plurality of electrical conductor vias 12.
• Performing a polishing of the overmolding via a CMP step so as to define a first surface extending substantially in the first extension plane and so as to expose the first plurality of electrical conductive vias 12 at said first surface;
• Formation of the first electrical conductive surface 11 of the first antenna 10 at said first surface, preferably by deposition of at least one electrically conductive element.

Module de découplage électromagnétique :Thus, surprisingly, this method makes it possible to solve the problem of compactness and efficiency by allowing the formation of a plurality of electrical conductor vias, rather than continuous sections, electrically connecting to the microelectronic circuit an antenna of the following type. UWB elevated relative to said microelectronic circuit.

Electromagnetic decoupling module :

As previously indicated, the present invention relates to solving a dual problem of efficiency and compactness.

Indeed, the AIP devices often have a plurality of antennas, and especially in the case where it has a UWB antenna, it may be necessary to use a second antenna, such as Bluetooth®, to increase the functionality of the device and to extend its modularity. It is in this type of situation that the present invention finds mainly application.

Due to the always decreasing size of microelectronic devices, the presence of a plurality of antennas leads to electromagnetic coupling problems causing performance losses relative to each antenna.

In order to solve this problem, the present invention relates to a device for transmitting and / or receiving radiofrequency signals comprising an electromagnetic decoupling module cleverly arranged between a first antenna and a second antenna.

This electromagnetic decoupling module, as will be explained later, is designed both to allow each antenna to present performance whose characteristics tend to be independent of the presence of another antenna, and while having a footprint reduced through, among other things, a clever positioning and design.

Typically, the electromagnetic decoupling module comprises an elevated structure, formed for example of an electrical conductive surface, disposed above a portion of a microelectronic circuit between a first antenna and a second antenna, preferably in the same plane. than one of the two antennas. In order to thus have this raised structure, the present invention can resort to the use of at least one connecting element, for example a plurality of vias electrically connected to the electrical conductive surface and to the microelectronic circuit, for example to raise said electrically conductive surface of the electromagnetic decoupling module.

According to one embodiment, the use of electrical conductor vias brings to the present invention on the one hand the possibility of raising the electrical conductive surface relative to the components of the microelectronic circuit, like one of the first and the second antenna, and secondly to enhance the electromagnetic shield phenomenon relative to each of the first and second antennas. Indeed, the vias electrically conductive participate in the phenomenon of electromagnetic shield between each of the first and second antennas.

The figure 1 previously presented illustrates the case of a device for transmitting and / or receiving radio frequency signals comprising a first antenna 10 of the UWB type and a second antenna 20 but not having an electromagnetic decoupling module. This type of device for transmitting and / or receiving radio frequency signals generally has limited efficiency by the electromagnetic coupling between its different antennas.

As previously described, this device for transmitting and / or receiving radiofrequency signals has a microelectronic circuit 2 disposed on a substrate 3 and comprising a plurality of microelectronic components 4.

In a manner similar to what has been described above, this device comprises the first antenna 10 which may for example be of the UWB type produced as previously indicated.

The second antenna 20, for example an antenna configured for Bluetooth® applications, is disposed at a second zone of the microelectronic circuit and in a second extension plane preferably different from the first extension plane of the first antenna 10. , but preferably parallel thereto. This second extension plane corresponds, for example, to the main extension plane of the microelectronic circuit 2. This second antenna 20 has a second electrically conductive surface 21 electrically connected to the microelectronic circuit 2.

According to one embodiment, the second zone represents at least 15%, preferably at least 20% and advantageously at least 25% of the surface of the microelectronic circuit 2.

As illustrated in figure 1 this second antenna 20 may have a coil shape extending mainly from the microelectronic circuit 2 according to a direction substantially collinear with the main direction of extension of the microelectronic circuit 2.

According to one embodiment, the second antenna 20 has a cross section, relative to its main extension dimension, increasing as it extends from the microelectronic circuit 2.

Advantageously, the second antenna 20 has a substantially two-dimensional geometric shape.

Preferably, the second antenna 20 is directly electrically and mechanically connected to the microelectronic circuit 2.

According to one embodiment, the transverse extension of the second antenna 20 perpendicular to the main direction of extension of the microelectronic circuit 2 is less than or equal to the transverse extension of the microelectronic circuit 2, and the longitudinal extension of the second antenna 20 relative to the main direction of extension of the microelectronic circuit 2 is less than or equal to the longitudinal extension of the microelectronic circuit 2.

According to a particular embodiment not shown, the second antenna 20 may comprise a second electrical conductive surface 21 raised relative to the microelectronic circuit 2 by means for example of a second connecting element of the type vias electrical conductors for example and / or of the type solid vertical walls.

In the configuration of this type of device for transmitting and / or receiving radio frequency signals, there is an electromagnetic coupling between the first antenna 10 and the second antenna 20. This electromagnetic coupling therefore disturbs the performance of each of the first 10 and second 20 antennas.

In order to highlight this electromagnetic coupling, the figure 3a illustrates the variation of the inverse transmission coefficient S12 40 of this device for transmitting and / or receiving radio frequency signals when no electromagnetic decoupling module is provided.

In this same figure, the curve 41 corresponds to the case where an electromagnetic decoupling module 30 between the first antenna 10 and the second antenna 20 is made. In particular, it will be noted the strong influence of this electromagnetic decoupling module 30 in the frequency band between 4GHz and 7 GHz by way of example.

Thus, in this frequency band which serves us here as an example of putting forward some of the advantages of the present invention, the presence of an electromagnetic decoupling module 30 allows the transmission device 1 and / or reception radio frequency signals to have enhanced radio frequency characteristics by limiting, and preferably suppressing, the electromagnetic coupling between the first and second antennas.

This electromagnetic decoupling module 30 is represented, according to one embodiment, in the Figures 2a and 2b which have a device 1 for transmitting and / or receiving radio frequency signals 1.

As previously, this device 1 for transmitting and / or receiving radiofrequency signals comprises a microelectronic circuit 2, a first zone carrying a first antenna 10 and a second zone carrying a second antenna 20.

In addition, this device 1 for transmitting and / or receiving radio frequency signals has a third zone carrying an electromagnetic decoupling module 30. This electromagnetic decoupling module 30 advantageously comprises an elevated structure relative to said microelectronic circuit 2.

This third zone is preferably arranged between the first zone and the second zone in the main direction of extension of the microelectronic circuit 2.

This elevated structure advantageously comprises an electrically conductive surface 31 disposed in a third extension plane.

According to one embodiment, the electromagnetic decoupling module 30 comprises at least one connecting element extending from the microelectronic circuit 2, preferably from a portion of the third zone of the microelectronic circuit 2, to said raised structure.

According to one embodiment, the connecting element may comprise a substantially vertical solid wall extending from the microelectronic circuit 2 to said raised structure.

Advantageously, and as previously indicated, it may be preferred to use electrical conductor vias 32 in order to form this connecting element so as to electrically connect the raised structure, in particular the electrically conductive surface 31, to the microelectronic circuit 2. for example to his plan of mass.

In addition, the use of electrical conductive vias 32 makes it possible to partially form at least one electromagnetic shielding for the microelectronic components 4 arranged between the electrically conductive surface 31 and the substrate 3 of the microelectronic circuit 2, in other words for the microelectronic components 4 arranged at the level of the third zone of the microelectronic circuit 2 with respect to the raised structure, preferably with respect to the electrically conductive surface 31.

Advantageously, the number of electrical conducting vias of the plurality of electrical conductor vias 32 is between 4 and 100, preferably between 10 and 80 and advantageously between 20 and 40.

Preferably, the electrical conductive surface 31 is supported by the electrical conductor vias 32 at at least 2 corners, preferably at least three corners and preferably at each of its corners.

According to one embodiment, the number of electrical conductor vias of the plurality of electrical conductor vias 32 is greater at one side of the electromagnetic decoupling module 30.

According to a preferred embodiment, the third extension plane corresponds to the plane of extension of one or the other of the first 10 and second 20 antennas, that is to say to the plane of extension of their surfaces. respective electric conductors 11 and 21.

Advantageously, the electric conductive surface 31 has a transverse extension perpendicular to the main direction of extension of the microelectronic circuit 2 less than or equal to the transverse extension of the microelectronic circuit 2.

According to one embodiment, the third zone represents at least 15%, preferably at least 25% and advantageously at least 35% of the surface of the microelectronic circuit 2.

Advantageously, the electrically conductive surface 31 of the electromagnetic decoupling module 30 has an area of at least 25%, preferably 50% and advantageously 75% of the area of one of the surface of the first antenna 10 according to the first extension plane and the surface of the second antenna 20 according to the second extension plane.

Preferably, the electrically conductive surface 31 of the electromagnetic decoupling module 30 has an area of at least 10%, preferably 20% and advantageously 30% of the area of the microelectronic circuit 2.

Advantageously, as visible in the figure 2b in particular, the electrical conductive surface 31 may be polygonal, and preferably rectangular. Preferably, the connecting element comprises vias on at least two sides of the polygonal structure; it can present via at each intersection between sides.

Advantageously, the electrical conductive surface 31 is a surface resulting from a metal deposit.

It should be noted, and this will be described more precisely later, that the electromagnetic decoupling module 30 and the first antenna 10 may comprise in part at least similar structural characteristics since they can be formed via the same method and preferably simultaneously.

In the figures 3a and 3b advantageously, the electrically conductive surface 31 of the electromagnetic decoupling module 30 is disposed in the plane of extension of the first electrical conducting surface 11 of the first antenna 10. This arrangement is particularly advantageous because it makes it possible to use the zone of the microelectronic circuit 2 not covered by the first electrical conductive surface 11 of the first antenna 10 and thus the electrical conductive surface 31 has a very small bulk.

Advantageously, the use of a plurality of vias 32 electrical conductors extending from the microelectronic circuit 2 to the electrical conductive surface 31 allows them to be electrically connected. These electrically conductive vias 32 therefore participate in the electromagnetic decoupling by playing a complementary role to that of the electrically conductive surface 31.

According to a preferred embodiment, the electrically conductive surface 31 is mechanically independent of the first electrical conductive surface 11 and the second electrically conductive surface 21. In other words, this means that the electrically conductive surface 31 does not have a physical contact point. direct neither with the first electrical conductive surface 11 nor with the second electrical conductive surface 21.

The Figures 3b and 3c show the reflection coefficient S11 of the first antenna 10 as a function of the frequency. Curve 42 of the figure 3b corresponds to the situation of the figure 1 that is to say, the absence of an electromagnetic decoupling module.

Conversely, curve 43 of the figure 3c corresponds to the situation of Figures 2a and 2b , that is to say the presence of an electromagnetic decoupling module 30.

It will be noted that on the figure 3c , a frequency band for which the reflection coefficient S11 of the first antenna 10, of the UWB type for example, has widened and for which its amplitude has been reduced.

This modification of the reflection coefficient S11 of the first antenna 10 is a marker of the electromagnetic decoupling effect enabled by the electromagnetic decoupling module 30.

About the figures 3d and 3d , these relate to the reflection coefficient S22 of the second antenna 20 as a function of the frequency. Curve 44 of the figure 3d corresponds to the situation of the figure 1 that is to say, the absence of an electromagnetic decoupling module. Curve 44 of the figure 3e corresponds to the situation of Figures 2a and 2b that is to say the presence of an electromagnetic decoupling module 30. It will be noted that the presence of an electromagnetic decoupling module 30 has only a minor effect on the performance of the second antenna 20, for example Bluetooth® type.

Indeed, relative to the positioning of the electromagnetic decoupling module 30 relative to the first 10 and the second 20 antennas in the Figures 2a and 2b , the electromagnetic decoupling has a more striking effect on the electromagnetic properties of the first antenna 10 than the second antenna 20.

Indeed, relative to the respective operating frequency bands of the first and second antennas, the electromagnetic decoupling module 30 allows an improvement in the electromagnetic performance of the first antenna 10 having the largest operating frequency band.

We will now describe the steps of a method of manufacturing a device 1 for transmitting and / or receiving radio frequency signals comprising an electromagnetic decoupling module according to a preferred embodiment. This manufacturing method incorporates many steps of the previously described method of manufacturing an elevated antenna from the vias formation technique described above.

• Fourniture du circuit microélectronique 2 ;
• Formation d'un premier élément de raccordement mécanique et électrique de la première antenne 10 au niveau de la première zone du circuit microélectronique 2 ;
  De manière préférée, ce premier élément de raccordement comprend une première pluralité de vias conducteurs électriques 12.
  Pour cette étape, il peut être avantageux de recourir à la technique précédemment décrite et illustrée au travers des figures 5a à 5c.
  Cette étape de formation peut nécessiter le masquage d'une partie au moins du circuit microélectronique 2, par exemple la deuxième zone et/ou la troisième zone du circuit microélectronique 2 peuvent être masquées de sorte à ne pas être exposées aux étapes que peut comprendre la formation du premier élément de raccordement.
• Formation de l'élément de raccordement de la structure surélevée du module de découplage électromagnétique 30 au niveau de la troisième portion du circuit microélectronique 2 ;
  De préférence, ledit élément de raccordement comprend la pluralité de vias conducteurs électriques 32. Pour cette étape, il peut être avantageux également de recourir à la technique précédemment décrite.
  De manière préférée, cette étape de formation des vias conducteurs électriques 32 est réalisée simultanément à l'étape de formation de la première pluralité de vias conducteurs électriques 12.
  Cette étape de formation peut également nécessiter le masquage d'une partie au moins du circuit microélectronique 2, comme par exemple la deuxième zone destinée à accueillir la deuxième antenne 20.
• Surmoulage du circuit microélectronique 2 de manière à recouvrir en partie au moins lesdits vias conducteurs électriques de la première pluralité de vias conducteurs électriques 12 et lesdits vias conducteurs électriques de la pluralité de vias conducteurs électriques 32. Selon un mode de réalisation, le circuit microélectronique 2 est surmoulé d'un matériau polymère ;
• De préférence, réalisation d'un polissage du surmoulage via une étape de CMP (de l'anglais « chemical mechanical polishing ») par exemple de sorte à définir une première surface s'étendant sensiblement selon le premier plan d'extension et une surface s'étendant sensiblement selon le troisième plan d'extension, de préférence coplanaire au premier plan d'extension et de sorte à exposer la première pluralité de vias conducteurs électriques 12 et la pluralité de vias conducteurs électriques 32 au niveau respectivement de la première surface et de ladite surface ;
• Formation de la première surface conductrice électrique 11 de la première antenne 10 au niveau de ladite première surface, de préférence par dépôt d'au moins un élément conducteur électrique. Pour cette étape, un masquage de ladite surface destinée à accueillir la structure surélevée du module de découplage électromagnétique 30 peut être réalisé afin de la protéger de ce dépôt. De même, un masquage de la deuxième zone peut être nécessaire.
• Formation de la surface conductrice électrique 31 du module de découplage électromagnétique 30 au niveau de ladite surface, de préférence par dépôt d'au moins un élément conducteur électrique. Ici également pour cette étape, un masquage de la première surface conductrice électrique 11 peut être réalisé afin de la protéger de ce dépôt. Selon un autre mode de réalisation préféré, la formation de la surface conductrice électrique 31 est réalisée simultanément à la formation de la première surface conductrice électrique 11.
• Optionnellement, retrait du surmoulage ;
• Formation de la deuxième antenne 20 au niveau de la deuxième zone du circuit microélectronique 2. Cette formation pouvant comprendre des étapes de gravure, masquage et de dépôts de matériaux conducteurs électriques.

Thus, this method can comprise at least the following steps:

• Supply of the microelectronic circuit 2;
• Forming a first mechanical and electrical connection element of the first antenna 10 at the first zone of the microelectronic circuit 2;
  Preferably, this first connection element comprises a first plurality of electrical conductor vias 12.
  For this step, it may be advantageous to use the technique previously described and illustrated through the Figures 5a to 5c .
  This formation step may require the masking of at least a portion of the microelectronic circuit 2, for example the second zone and / or the third zone of the microelectronic circuit 2 may be masked so that not to be exposed to the steps that can comprise the formation of the first connecting element.
• Formation of the connecting element of the raised structure of the electromagnetic decoupling module 30 at the third portion of the microelectronic circuit 2;
  Preferably, said connecting element comprises the plurality of electrical conductor vias 32. For this step, it may also be advantageous to use the technique described above.
  Preferably, this step of forming the electrical conducting vias 32 is carried out simultaneously with the step of forming the first plurality of electrical conductor vias 12.
  This formation step may also require the masking of at least a part of the microelectronic circuit 2, such as the second zone intended to receive the second antenna 20.
• Over-molding of the microelectronic circuit 2 so as to partially cover at least said electrical conductor vias of the first plurality of electrical conductor vias 12 and said electrical conductor vias of the plurality of electrical conductor vias 32. According to one embodiment, the microelectronic circuit 2 is overmolded with a polymeric material;
• Preferably, polishing the overmoulding via a CMP (chemical mechanical polishing) step, for example, so as to define a first surface extending substantially along the first extension plane and a surface extending substantially along the third extension plane, preferably coplanar with the first extension plane and so as to expose the first plurality of electrical conductor vias 12 and the plurality of electrical conductor vias 32 respectively at the first surface and the said surface;
• Formation of the first electrical conductive surface 11 of the first antenna 10 at said first surface, preferably by deposition of at least one electrically conductive element. For this step, a masking of said surface intended to accommodate the raised structure of the electromagnetic decoupling module 30 can be made to protect it from this deposit. Similarly, masking of the second zone may be necessary.
• Formation of the electrically conductive surface 31 of the electromagnetic decoupling module 30 at said surface, preferably by deposition of at least one electrically conductive element. Here also for this step, a masking of the first electrically conductive surface 11 can be made to protect it from this deposit. According to another preferred embodiment, the formation of the electrically conductive surface 31 is performed simultaneously with the formation of the first electrically conductive surface 11.
• Optionally, removal of overmolding;
• Formation of the second antenna 20 at the second zone of the microelectronic circuit 2. This formation may include etching, masking and deposition steps of electrically conductive materials.

Thus, surprisingly, the vias formation technique and the method of manufacturing an antenna raised from this vias formation technique have a synergy with the resolution of the electromagnetic decoupling problem between the first antenna 10 and the second antenna. Antenna 20. This technique and this method make it possible to have the electrically conductive surface 31 in the same plane of extension as the first electrically conductive surface 11, thus allowing better electromagnetic decoupling between the first 10 and second antennas.

The present invention thus makes it possible, in a non-limiting embodiment, to increase the efficiency of the AIP devices without affecting their compactness via, inter alia, the use of an original method of forming an elevated antennal system advantageously used for the production of an electromagnetic decoupling module for example and an antenna then located in the same extension plane.

The invention is not limited to the embodiments described, but extends to any embodiment within the scope of the claims.

REFERENCES

• 1. Device for transmitting and / or receiving radio frequency signals
• 2. Microelectronic circuit
• 3. Substrate
• 4. Microelectronic components
• 5. Resin
• 10. First antenna
• 11. First electrical conductive surface
  • 11a. First portion
  • 11b. Second portion
  • 11c. Third portion
  • 11d. Slot
  • 11th. Electrically conductive flank
• 12. First plurality of electric conductor vias
  • 12a. Proximal end of a via of the first plurality of electrical conductor vias
  • 12b. Distal end of a via of the first plurality of electrical conductor vias
• 20. Second antenna
• 21. Second electrical conductive surface
• 22. Second plurality of electrical conductor vias
  • 22a. Proximal end of a via of the second plurality of electrical conductor vias
  • 22b. Distal end of a via of the second plurality of electrical conductor vias
• 30. Electromagnetic decoupling module
• 31. Electrical conductive surface
• 32. Plurality of electrical conductor vias
  • 32a. Proximal end of a via of the plurality of electrical conductor vias
  • 32b. Distal end of a via of the plurality of electrical conductor vias
• 40. Coefficient of inverse transmission between the first antenna and the second antenna in the absence of the electromagnetic decoupling module
• 41. Inverse transmission coefficient between the first antenna and the second antenna in the presence of the electromagnetic decoupling module
• 42. Coefficient of reflection of the first antenna in the absence of the electromagnetic decoupling module
• 43. Coefficient of reflection of the first antenna in the presence of the electromagnetic decoupling module
• 44. Coefficient of reflection of the second antenna in the absence of the electromagnetic decoupling module
• 45. Coefficient of reflection of the second antenna in the presence of the electromagnetic decoupling module
• 60. Cabling tool
• 61. Electrical conductor
• 62. Electrical conductive area
• 63. Electrical non-conductive area

Claims (15)

Device (1) for transmitting and / or receiving radiofrequency signals comprising at least: A microelectronic circuit (2) extending in a main extension plane and in a main direction of extension; A first antenna (10) carried by a first zone of said microelectronic circuit (2) and extending in a first extension plane; A second antenna (20) carried by a second zone of said microelectronic circuit (2) extending in a second extension plane; the device (1) further comprising an electromagnetic decoupling module (30) between the first antenna (10) and the second antenna (20) carried by a third zone of said microelectronic circuit (2) disposed between the first zone and the second zone; the electromagnetic decoupling module (30) comprising at least one raised structure relative to said microelectronic circuit (2) and at least one connecting element of said raised structure to said microelectronic circuit (2),
the device being characterized in that : it comprises an overmolding of the microelectronic circuit (2) configured so as to partly cover at least the at least one connecting element and the microelectronic circuit (2) so as to define a surface, preferably plane, extending substantially according to a third extension plan; the connecting element comprises a plurality of electrical conducting vias (32) electrically connected to said raised structure and to said microelectronic circuit (2) and extending from said microelectronic circuit (2) to the raised structure; the raised structure is a deposit of at least one metallic conductive element situated on said surface. Device (1) according to the preceding claim, wherein the raised structure is supported by the electrical conducting vias (32) at at least two of its corners, preferably at least three of its corners and even more preferably at the level of each of its corners. Device (1) according to one of the preceding claims, wherein said raised structure comprises at least one electrically conductive surface (31) extending along a third coplanar extension plane to at least one of the first extension plane and the second extension plane. Device according to any one of the preceding claims, wherein the overmolding is in at least one polymeric material. Device according to any one of the preceding claims, wherein the diameter of the electrical conductive vias (32), according to their transverse dimension, and between 10 microns and 500 microns. Device (1) according to one of the preceding claims, wherein the plurality of electrical conductive vias (32) is disposed on at least a portion of the third zone of the microelectronic circuit (2). Device (1) according to any one of the preceding claims, wherein the first extension plane and the second extension plane are offset relative to a direction perpendicular to the first extension plane and the second extension plane. Device (1) according to any one of the preceding claims, wherein the electromagnetic decoupling module (30) is mechanically secured to the first antenna (10) and the second antenna (20) only via the microelectronic circuit (2). Device (1) according to any one of the preceding claims, wherein the first antenna (10) comprises a first electrical conductive surface (11) extending in the first extension plane, the second antenna (20) comprises a second electrical conductive surface (21) extending along the second extension plane and the raised structure (31) of the electromagnetic decoupling module (30) has at least one transverse extension, perpendicular to said main extension direction, greater than or equal to at the transverse extension, perpendicular to said main extension direction, of the first electrical conducting surface (11) and at the transverse extension, perpendicular to said main extension direction, of the second electrical conducting surface (21). Device according to any one of the preceding claims, wherein the microelectronic circuit (2) comprises a mass and wherein the raised structure of the electromagnetic decoupling module (30) is electrically connected to said mass, preferably through said connecting element . A method of manufacturing a device (1) for transmitting and / or receiving radio frequency signals according to any one of the preceding claims, comprising at least the following steps: • Supply of the microelectronic circuit (2) having a main extension plane and an antenna called second antenna (20) at the second zone of said microelectronic circuit (2) • forming the first antenna (10) at the first zone of said microelectronic circuit (2); • Formation of the electromagnetic decoupling device (30) at the third zone of said microelectronic circuit (2), this forming step comprising at least the following successive steps: i. Formation of at least one connecting element at the third zone of said microelectronic circuit (2), the connecting element comprising a plurality of electrical conducting vias (32) electrically connected to said raised structure and to said microelectronic circuit (2) ) and extending from said microelectronic circuit (2) to the raised structure; ii. Over-molding of the microelectronic circuit (2) so as to partially cover at least the at least one connecting element and the microelectronic circuit (2) so as to define a surface, preferably plane, extending substantially along a third plane of 'extension ; iii. Formation of the raised structure of the electromagnetic decoupling module (30) by deposition of at least one metallic conductive element at said surface. Method according to the preceding claim wherein the step of forming the raised structure (31) of the electromagnetic decoupling module (30) by deposition of at least one electrically conductive element is performed by selective plasma spraying. Method according to any of the two preceding claims wherein the step of forming at least one connecting element at the third zone of said microelectronic circuit (2) comprises at least the following steps: • Wiring an end of at least one electrical conductor wire (61) at a portion of the third zone of said microelectronic circuit (2); • Cutting at least a portion of said soldered electrical conductor wire (61) at a portion of the third zone of said microelectronic circuit (2); • Arranging said soldered electrical conductor wire (61) at a portion of the third zone of said microelectronic circuit (2) so that it has an orthogonal extension direction to the main extension plane of said microelectronic circuit ( 2). A method according to any one of the three preceding claims wherein the step of forming the first antenna (10) comprises at least the following steps: • forming a first plurality of electrical conductor vias (12) at the first zone of the microelectronic circuit (2); Overmoulding of the microelectronic circuit (2) so as to partially cover at least said electrical conductor vias of the first plurality of electrical conductor vias (12) so as to define a first surface, preferably plane, extending substantially according to the first extension plan; • Formation of a first electrical conductive surface (11) of the first antenna at said first surface, preferably by deposition of at least one electrically conductive element. A method as claimed in any one of the preceding claims wherein the step of forming the electromagnetic decoupling module (30) is performed concurrently with the step of forming the first antenna (10).

Images