RU2636575C1 - Method of manufacturing of plastic radioelectronic nodes and interconnections - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: method involves manufacturing of a rigid base in the form of a supporting metal ring. Then, a metal foil is fixed on the supporting metal ring. Apply a photosensitive material on one side of the metal foil and form a topological drawing with photolithography in this layer. After this, the first layer of silicone polymer is applied to the drawing formed by photolithography. Then the topological drawing is formed by photolithography on the other side of the metal foil and etched through the metal foil. Finally, the second layer of silicone polymer is applied to the obtained topological drawing.

EFFECT: reduction of labour intensity of manufacturing, expansion of functionality and increase in reliability of plastic radioelectronic nodes and interconnections.

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Description

The present invention relates to instrumentation, and in particular to a technology for the production of plastic electronic devices and interconnects that have the ability to compensate for large deformations (tension and compression), while maintaining a functional state, and to a method for producing such plastic devices and interconnects for the production technology of electronic components.

A known method of manufacturing a plastic interconnect of an electronic device for communication of two or more electronic devices, including the formation of switching between two devices by photolithography. In this case, the conductor for interconnection is preferably spiral-shaped [1]. Plastic interconnects are V-shaped on a pre-fixed base, after removing the fastening and turning the base, the conductors should form a spiral shape. The disadvantages of this method are the complexity of the process, the need for manufacturing complex equipment for fixing the base, the high complexity, the duration of the technological formation of the layers and the high cost of its manufacture.

Closest to the claimed technical solution is a method of manufacturing a plastic electronic device, which we adopted for the prototype, including the manufacture of the base, the connection of the switching layer with a rigid base and the formation of a topological pattern [2]. The switching layer is enhanced by an intermediate flexible layer and has a predetermined shape.

The disadvantages of this method is the large number of operations, relatively low reliability and poor maintainability, since when re-installing electronic components, sections of the reinforcing material can easily be damaged. So the manufactured sample must be fixed over the entire surface to the technological base, this requires additional operations (including high-temperature) and complex materials. In addition, this entails the creation of tense areas in the places of formation of conductors and contacts, which, after removing the technological base and before applying subsequent topological layers, can lead to rupture of the created electrical connections. Gluing is carried out after the formation of a topological pattern on one side. And this increases the risk of damage to contacts and connections. In addition, additional operations are required to prepare for gluing and operations to remove the adhesive layer. Another disadvantage is the need to manufacture special casting molds for each individual device, which significantly affects the complexity and cost.

The problem to which the invention is directed is to reduce the complexity of manufacturing, expand the functionality and increase the reliability of plastic electronic components and interconnects.

To achieve this goal in a method of manufacturing a plastic electronic components and interconnects, including the manufacture of the base, the connection of the switching layer with a rigid base, the formation of a topological pattern and the strengthening of the switching layer with an intermediate flexible layer, a rigid base is made - a support metal ring, a metal foil is fixed on the support metal ring , an intermediate flexible layer is applied on one side of the metal foil, a photolithography pattern is formed in it, rvy silicone polymer layer formed on a photolithography pattern is formed by photolithography topological figure on the other side of the metal foil, etched through the metal foil is applied to the second layer of the organosilicon polymer obtained topological pattern.

Signs that distinguish the claimed method from the known is that they make a rigid base - a supporting metal ring. Fix the metal foil on the support metal ring. A photosensitive material is applied on one side of the metal foil. A topological pattern is formed by photolithography in a layer of photosensitive material. The first layer of organosilicon polymer is applied to the pattern formed by photolithography. A topological pattern is formed by photolithography on the other side of the metal foil. Poison metal foil through and through. A second layer of organosilicon polymer is applied to the resulting topological pattern.

The invention is illustrated by the drawings of FIG. 1 (a, b, c, d, d, e, f, h, and, k) is a sequence of technological operations of a method for manufacturing plastic electronic components and interconnects,

Where:

1 - a layer of metal foil,

2 - rigid support ring,

3 - photosensitive material

4 is a topological drawing in a layer of photosensitive material,

5 - the first layer of organosilicon polymer,

6 - layer of photoresist,

7 is a drawing formed in a photoresist layer,

8 is a topological drawing in a metal layer,

9 - the second layer of organosilicon polymer.

In FIG. 2 shows a plastic electronic assembly with formed S-shaped conductive channels manufactured by the proposed method.

The method is implemented as follows. The manufacturing process of plastic electronic components and interconnects begins with the manufacture and preparation of special equipment in the form of a rigid support ring 2. The ring can be made of any material that is thermally and chemically resistant to etchants used in subsequent operations, preferably metal. A method of manufacturing a rigid support ring does not matter. If necessary, the working side of the support ring is machined in order to obtain a smooth surface with low roughness. The use of a rigid support metal ring allows you to fix the conductive layer of metal - the foil, which is used for the manufacture of plastic bases (printed circuit boards) for microelectronic devices and form a shape for the applied silicone polymer, which plays the role of a structural base in this method.

The next step is to fix the metal foil 1, later acting as a switching layer, on a rigid support ring (Fig. 1A). Fastening can be carried out using various adhesives by gluing with the application of the required pressure. Depending on the fixing method and the adhesive used, certain drying modes are selected to achieve reliable fixing.

A photosensitive material 3 is applied to the metal foil 1 from the inside of the support ring 2 (Fig. 1b). The material may be a photosensitive material with dielectric properties and high tensile strength. The most optimal way to obtain a uniform layer of photosensitive material is centrifugation, however, any other well-known method can be used. Depending on the viscosity of the selected material, the optimum application mode is selected. Then the material is dried in a convection oven according to the temperature conditions specified in the technical specifications of the selected material. This material acts as a buffer layer between the switching layers and the plastic structural base. It prevents excessive stretching, gives the necessary rigidity and has high adhesion to both metals and organosilicon polymers.

Using the method of photolithography, a topological pattern is formed in the layer of photosensitive material 3 (Fig. 1c), also marks are formed in the layer for subsequent combination of layers.

The first layer of organosilicon polymer 5 is applied to the pattern formed in the photosensitive material (Fig. 1d). The polymer can be applied in any known manner — by spraying, centrifuging, dipping, watering. The use of an organosilicon polymer with unique electrophysical and mechanical parameters as a structural material provides high technological and operational characteristics to plastic multilayer patch boards. The use of organosilicon polymer expands the functionality of plastic printed circuit boards manufactured in this way for microelectronic devices with a high degree of integration, that is, they actually have unlimited possibilities for placing microelectronic components in a given volume of the device — the ability to adapt the form. Such plastic printed circuit boards for microelectronic devices can stretch, bend and twist together with the object on which they are installed. In addition, the level of moisture protection and resistance to vibration increases sharply. The proposed method allows to reduce weight and size parameters. Reliability increases, vibration resistance, heat resistance and moisture protection of electronic components are increased. In addition, the use of the proposed method can improve the controllability, reproducibility and reliability of compounds in a plastic electronic device.

A photoresist 6 is applied to another surface of the foil 1 (Fig. 1e). In the photoresist layer, a pattern is formed by photolithography (Fig. 1e). Like metal (Fig. 1g). The photoresist is removed (Fig. 1h). The processes of forming a pattern and etching of a metal are typical and do not differ from those in the processes of forming, for example, traditional printed circuit boards. As a result, we have a plastic microelectronic assembly with S-shaped conductive channels formed (Fig. 2). This form of conductors is caused by the need to stretch and compress the manufactured sample along the X and Y axes. Due to the non-plastic nature of metals, the switching pattern of traditional forms will lead to defects and ruptures in the conductive circuits. After reviewing and conducting theoretical studies of various forms of conductors, the optimal S-shape was identified. It allows you to achieve stretchings up to 100% without the occurrence of tears and other defects. Also, to increase reliability, the switching pattern is recommended to be made of several duplicate conductive lines of smaller thickness (for example, instead of a conductive line 100 microns thick, it is recommended to make 4 conductive lines 20 microns thick with small gaps).

A second layer of organosilicon polymer 9 is applied to the resulting conductive topological pattern (Fig. 1i). If there is a need for soldering or welding processes for the installation of components, first soldering / welding is carried out, then a second layer of silicone polymer is applied. In addition, the formation of subsequent layers of switching and the creation of a multilayer base. To create interlayer transitions, various types of liquid and / or dry etching can be used. The formation of subsequent layers of switching can be carried out by additive methods with the subsequent process of photolithography in order to obtain a picture. After completion of all the processes of layer formation, the manufactured sample is separated from the snap (Fig. 1K).

Example

The example below describes the process of forming a plastic connector (cable) based on silicone material brand SIEL. A rigid support metal ring is made of AISI304 stainless steel sheet (Art. 08X12H10) 0.8 × 250 × 500 with a diameter of 100 mm and an inner diameter of 80 mm.

Then, with a heat-resistant epoxy adhesive, a copper foil DPRNT M1 0.015 × 210 GOST 5638-75 is glued to the stainless steel ring. To achieve a high-quality one-piece connection, a pressure of 10 N is applied to the sample and placed in a convection oven to dry the glue.

A photosensitive polyimide varnish is applied to the copper foil from the inside of the ring. To obtain a uniform and defect-free coating, varnish is applied in a centrifuge at a speed of 2500 rpm for 30 s. The polyimide layer acts as a buffer. The intermediate layer allows you to reduce stress on the metal layer during subsequent stretching and compression of the manufactured devices, in addition, the polyimide has high adhesion to the metal and to the organosilicon material. After application, the sample is placed in a convection oven for drying photolac. It is necessary to observe the temperature profile of drying in order to avoid further difficulties with exposure and the manifestation of photosensitive varnish.

Then the photosensitive varnish is exposed through a photo mask. Exposure Mode:

Exposure time - 22 sec; Lamp power - 25 mW / cm ² .

Further, the varnish appears in the following modes:

Development time - 20 seconds; Rinsing in deionized water - 40 sec; Blowing with nitrogen, drying from moisture - 50 sec; The temperature of the solution is room temperature.

After that, the silicone polymer "SIEL" is applied. The polymer is applied to the inside of the sample. The approximate polymer thickness is 0.65 mm, the polymer is poured to the brink of a stainless steel ring. Drying of the organosilicon polymer can be carried out in various modes, both at room temperature and at elevated temperatures, in this example, the regime was applied: 60 min at room temperature, 60 min at 100 ° C in a convection oven. This layer will continue to serve as a structural basis.

Next, a photoresist is applied to the surface of the copper, exposed, manifested by the developer. The sample is immersed in an etchant to etch copper.

Photoresist etching mode.

The sample is immersed in an etchant for copper for 6 seconds, then washed in deionized water and dried from moisture in a stream of hot air from both sides. Then the photoresist is removed, the solvent dimethylformamide is used. Photoresist removal is carried out in the following modes.

Removal time - 10 ± 2 min; Rinsing in deionized water - 10-20 minutes.

An organosilicon polymer is applied to the side with a conductive pattern for additional protection and sealing of the sample. Application can be carried out either manually or in a centrifuge. Due to the fact that the material is self-leveling, it is enough to apply the material evenly over the entire surface and leave it for a while so that the material spreads evenly over the entire surface. Drying is carried out at the previously indicated mode.

Thus, manufactured by the proposed method, the products allow their use in a wide range of operating temperatures, a wide range of vibration effects in comparison with the prototype. The electronic components made in this way have high ductility, flexibility, and strength compared to the prototype, which expands their functionality. The method is intended for mounting electronic components or for manufacturing and connecting a plastic cable to other devices or printed circuit boards, as well as the materials and coatings used in their formation, also allow for high-density intercell connection in electronic equipment. Products made according to the proposed method make it possible to create devices of the same size and then change their shape and dimensions to the necessary, this will allow you to create devices that are built into complex-shaped cases and the formation of 3D structures. The possibility of deformation into the necessary form allows you to create wearable devices and wearable devices. In addition, it becomes possible to create various sensors and sensors.

The resulting product has unique properties with the ability to stretch, compress and take the necessary shape, while maintaining its functional properties and having increased reliability, vibration resistance.

Information sources

U.S. Patent No. 2002/0094701,

Patent WO No. 2010/086416 - prototype.

Claims (1)

A method of manufacturing a plastic electronic components and interconnects, including the manufacture of the base, the connection of the switching layer with a rigid base, the formation of a topological pattern and the strengthening of the switching layer by an intermediate flexible layer, characterized in that they make a rigid base - a support metal ring, fix the metal foil to the support metal ring, apply an intermediate flexible layer on one side of the metal foil, form a photolithography pattern in it, apply the first layer of cre of an organo-organic polymer onto a pattern formed by photolithography, a topological pattern is formed by photolithography on the other side of the metal foil, etched through the metal foil, a second layer of organosilicon polymer is applied to the obtained topological pattern.

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