JP3946578B2 - Manufacturing method of wiring board provided with passive element, wiring board provided with passive element - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a wiring board provided with passive elements and a wiring board provided with passive elements, and more particularly to a method for manufacturing a wiring board provided with passive elements and a passive element suitable for improving the characteristics of the passive elements. It is related with the wiring board provided with.
[0002]
[Prior art]
As portable electronic devices become smaller, lighter, and thinner, chip components such as L (inductors, coils), C (capacitors, capacitors), and R (resistors) have been reduced. In addition, techniques for embedding passive components such as C and L in one wiring board to form composite components have been developed. Such integration with a wiring board is actively performed especially with a multilayer ceramic substrate or the like, and is used in, for example, an RF (radio frequency) module of a cellular phone.
[0003]
For multilayer ceramic substrates, for example, a necessary number of green sheets (ceramic material sheets before firing) on which coil patterns and capacitor electrode patterns are formed by printing thick film conductor paste are prepared, and these are arranged in a predetermined order. It is created by laminating, thermocompression bonding and firing at the same time.
[0004]
Furthermore, a plurality of sheets having different dielectric constants are prepared, and the sheets are selected in accordance with the characteristics of the passive component to be manufactured. This is because the ceramic material of the layer constituting the inductor has a low dielectric constant green sheet that can ensure a high self-resonance frequency and a high Q value, and the capacitor that constitutes the capacitor has a high dielectric constant green sheet. Each is a choice. By such a combination, it is possible to build a LC composite component with higher functionality.
[0005]
[Problems to be solved by the invention]
All of these techniques are examples in which ceramics are used as a wiring board material. However, in anticipation of the case where the operating frequency of the RF circuit used in the cellular phone will reach 10 to 20 GHz in the future, an organic resin having a lower relative dielectric constant can be used as a substrate material. It is considered important in terms of product costs. At present, if an organic resin having a dielectric constant lower than that of ceramics is used as the substrate material (interlayer insulating layer), when a passive element such as a capacitor is formed in the same manner as a multilayer ceramic substrate, the area as an element is reduced. There is a possibility that it becomes large or a desired characteristic cannot be obtained.
[0006]
In addition, there are the following reported examples of what is called a hybrid laminated substrate. That is, first, a substrate material in which a dielectric material or a magnetic material is mixed into an organic polymer material is prepared according to the characteristics of the passive element to be formed. This substrate material is etched to form patterned capacitor layers and coil layers, which are laminated in a predetermined order to form a hybrid laminated substrate.
[0007]
However, in this method, the multilayered substrate may be warped due to a difference in characteristics such as a thermal expansion coefficient between the substrate materials. In addition, since only one type of passive element specialized for each layer can be formed, the degree of freedom of passive element arrangement design is low, and the number of layers tends to increase as a whole, which is not suitable for miniaturization.
[0008]
As another multilayer organic resin substrate, there is a substrate in which R, C, and L are formed by sequentially printing a resistance paste, a dielectric paste, and a conductive paste. However, since the paste that can be used in this case is limited to a type that can complete the heat treatment at a lower temperature due to the heat resistant temperature of the organic resin used as the insulating layer, the desired characteristics as a passive element may not be obtained. Conceivable.
[0009]
The present invention has been made in consideration of the above situation. That is, an object of the present invention is to provide a method for manufacturing a wiring board provided with passive elements having improved characteristics, and a wiring board provided with such passive elements.
[0015]
[Means for Solving the Problems]
  In order to solve the above problems, the present invention relates toIn the method of manufacturing a wiring board including a passive element, a dielectric is provided on at least the first surface of the second metal foil of the first and second metal foils having a first surface and a second surface, respectively. A step of applying a paste, a step of applying a conductive paste so as to cover the first surface to which the dielectric paste is applied, including the applied dielectric paste, and the first An insulating plate having thermoplasticity and thermosetting properties is disposed opposite to the first surface of the metal foil, and the surface of the insulating plate is opposed to a surface different from the surface facing the first metal foil. The step of arranging the first surface of the second metal foil and the three members of the arranged first metal foil, insulating plate, and second metal foil are laminated and pressurized and heated to be integrated. A step of forming a wiring board and at least the second gold of the formed double-sided wiring board; Characterized by comprising a step of patterning the foil.
[0016]
That is, the dielectric paste is applied on the metal foil. Therefore, treatments such as heat treatment of the paste (for example, drying, firing, thermosetting, etc.) can be performed regardless of the heat-resistant temperature of the insulating plate. In this way, for example, a metal foil having a heat-treated paste (dielectric) is laminated with an insulating plate, so that a wiring board having a passive element (in this case, a capacitor) having excellent characteristics can be obtained. .
[0017]
In this case, the dielectric can be further sandwiched between the conductor formed from the conductive paste and the metal foil, so that a so-called parallel plate type capacitor is formed. Thereby, a high-capacitance capacitor can be formed.
[0018]
  Further, according to the present inventionAnotherIn the method of manufacturing a wiring board having passive elements, at least the first surface of the second metal foil of the first and second metal foils having the first surface and the second surface is dielectric. A step of applying a body paste; a step of applying a first conductive paste so as to cover the applied dielectric paste and to extend onto the first surface to which the dielectric paste is applied; The applied firstofA step of applying a second dielectric paste so as to include the conductive paste; and the first surface including the second dielectric paste applied to the first surface. A step of applying a second conductor paste so as not to come into contact with the first conductor paste, and a thermoplastic and heat-sensitive material facing the first surface of the first metal foil. Disposing a curable insulating plate, and disposing the first surface of the second metal foil opposite to a surface different from the surface of the insulating plate opposite to the first metal foil; A step of forming a double-sided wiring board by laminating, pressing and heating the arranged first metal foil, insulating plate, and second metal foil to form a double-sided wiring board; and And patterning the second metal foil at least. That.
[0019]
That is, the dielectric paste and the conductive paste are applied on the metal foil. Therefore, treatments such as heat treatment (for example, drying, firing, thermosetting, etc.) of these pastes can be performed regardless of the heat-resistant temperature of the insulating plate. In this way, for example, a metal foil having a heat-treated paste (dielectric) is laminated with an insulating plate, so that a wiring board having a passive element (in this case, a capacitor) having excellent characteristics can be obtained. .
[0020]
In this case, the dielectric is further sandwiched between the conductor formed from the conductive paste and the metal foil, and the second dielectric is formed from the conductor and the second conductive paste. And so-called parallel plate type capacitors can be formed in multiple layers. Thereby, a capacitor having a higher capacity can be formed. Such a multilayer capacitor can be further increased in capacity by multilayering a dielectric and a conductor with a dielectric paste and a conductive paste.
[0026]
  Further, according to the present invention, ReceivedA wiring board provided with a moving element includes an insulating plate having a first surface and a second surface, and a layered conductive film provided by sinking in the thickness direction of the insulating plate on the second surface of the insulating plate. A layered dielectric provided in contact with a part of the upper surface of the layered conductor and sinking in the thickness direction of the insulating plate; and the layered conductive provided on the second surface of the insulating plate. Body andLayereddielectricTo the bodyAnd a wiring layer having individual connections.
[0028]
  thisThe wiring board described aboveMadeA wiring board that can be manufactured by a manufacturing method.
[0062]
DETAILED DESCRIPTION OF THE INVENTION
  BookThe wiring board according to the invention includes, as an embodiment, a second layered dielectric provided under the lower surface of the layered conductor and a lower surface of the second layered dielectric, and the wiring And a second conductor connected to the layer., And may be. It has a multilayered parallel plate type capacitor.
[0066]
  Embodiments of the present invention will be described below with reference to the drawings.First,1 (a) and 1 (b) show an embodiment of the present invention.To help explainIt is a figure which shows the process which manufactures a double-sided wiring board with a manufacturing method.
[0067]
First, as shown in FIG. 1A, a metal foil (for example, copper foil) 1 is prepared. A dielectric paste is applied on the metal foil 1 so as to be a dielectric 2 of a passive element (capacitor) necessary as a wiring board. The application method is not particularly limited. For example, when screen printing is used, the necessary number of the entire surface can be increased with high productivity and considerably high accuracy. As the dielectric paste, for example, a composition in which a powder of barium titanate, which is a high dielectric material, is dispersed in a resin binder can be used. As an example, dielectric paste CX-16 manufactured by Asahi Chemical Research Laboratory can be used.
[0068]
Further, a resistance paste is applied on the metal foil 1 so as to be a passive element (resistor) resistor 3 necessary as a wiring board. The method for applying the resistance paste is the same as described above. As the resistance paste, for example, a composition in which a powder of a resistance material is dispersed in a resin binder can be used. As an example, resistance paste TU-15-8, TU-50-8, or TU-100-8 manufactured by Asahi Chemical Research Laboratory can be used.
[0069]
In general, it is preferable to apply the dielectric paste and the resistance paste separately, and separately perform a treatment such as drying. This is because the dried state is more suitable for the maintenance without interfering with the previous application state. This treatment such as drying can be performed at an appropriate temperature as a treatment for the dielectric paste and the resistance paste itself, irrespective of the heat-resistant temperature of an insulating plate (organic material) described later. Therefore, the selection of the kind is wide and contributes to formation of a more accurate passive element.
[0070]
Furthermore, in order to make the resistor 3 more highly accurate, a method (post-processing) as shown in FIGS. 14A and 14B may be used. FIG. 14A and FIG. 14B are diagrams for explaining the disorder of the shape at the edge of the resistor (/ dielectric / conductor) applied to the metal foil and the improvement thereof. FIG. 14A is a cross-sectional view, and FIG. 14B is a top view thereof.
[0071]
As shown in FIG. 14A, the resistor 3 applied and formed by a method such as screen printing is generally formed with a shape such as a thickness at an end thereof slightly different from the inner portion ( Edge effect). Such a change in thickness causes a disturbance in the sheet resistance value (which is one of characteristic values as a resistor and is a resistance value between opposing sides of a square shape). Therefore, the end 30 of the resistor 3 is removed when the resistor 3 is formed on the metal foil 1. For such removal, for example, laser light can be used. By such removal, the thickness becomes uniform, and a resistor closer to the resistance value predicted from the sheet resistance value can be formed. In the case of the dielectric 2 as well, high accuracy can be achieved.
[0072]
As described above, the coated and formed metal foil 4 having the resistor 3 and the dielectric 2 formed on the surface can be formed. Next, as shown on the upper side of FIG. 1 (b), the resistor 3 and the dielectric 2 side of the two coated / formed metal foils 4 are connected to the wiring board so as to face both surfaces of the prepreg to be the insulating plate 5. It arranges in the predetermined position required as. For example, the prepreg is obtained by impregnating a reinforcing material such as glass fiber with a curable resin such as an epoxy resin. Moreover, it is in a semi-cured state before curing, and has thermoplasticity and thermosetting properties.
[0073]
Next, as shown in the center of FIG. 1 (b), the coated / formed metal foil 4, the insulating plate 5, and the other coated / formed metal foil 4 are laminated, pressurized and heated to be integrated. A double-sided wiring board 6 is obtained. In the double-sided wiring board 6, the dielectric 2 and the resistor 3 are integrated by sinking in the thickness direction of the insulating board 5. This is because the prepreg to be the insulating plate 5 is thermoplastic and thermosetting.
[0074]
Next, as shown on the lower side of FIG. 1B, the metal foils 1 on both sides are patterned into a pattern 1a necessary as a wiring board. By this patterning, a double-sided wiring board 7 on which at least both end electrodes of the dielectric 2 and the resistor 3 are formed can be obtained. For the patterning, for example, a known method such as formation of a mask by applying / exposure of a photoresist or etching of the metal foil 1 by this mask can be used.
[0075]
In addition, the resistor 3 may be trimmed by using both end electrodes formed by this patterning as resistance value measuring terminals. Trimming is a process in which, for example, a part of the resistor 3 is burned out to match a predetermined resistance value using laser light.
[0076]
Although not shown in the drawings, a solder resist or a plating layer including the pattern 1a is formed, a surface mount component is mounted on the pattern 1a, and a semiconductor chip is flip chip mounted by a known method. it can. Further, as is well known, through-holes are formed in the double-sided wiring board 7 and a conductive layer is formed on the inner surface thereof, so that the double-sided wiring board 7 can be electrically connected to each other. Moreover, according to the etching of the metal foil 1 as described above, a spiral inductor can be formed, but such a through hole can be used for the inner terminal in that case.
[0077]
  As described aboveExampleThen, since the dielectric 2 and the resistor 3 are formed on the metal foil 1 in advance by selecting materials from a wide selection range, it is possible to mix capacitors and resistors having excellent characteristics in the same layer. it can. Moreover, since an organic material is used as the insulating plate 5, the weight can be reduced as compared with ceramics.
[0078]
In the above description, it has been described that the dielectric 2 serving as a capacitor and the resistor 3 serving as a resistor are formed by applying a paste-like composition, respectively. However, in order to form a spiral inductor in addition to these. Alternatively, a conductive paste as a paste-like composition may be applied in a spiral shape on the metal foil 1 in advance.
[0079]
  nextThe figure2 (a) and FIG. 2 (b) show the present invention.oneEmbodimentAnother useful reference in explainingIt is a figure which shows the process which manufactures a double-sided wiring board with a manufacturing method, and the same code | symbol is attached | subjected to the site | part same as FIG. 1 (a) and FIG.1 (b). The description of the same part is omitted.
[0080]
  thisExampleAs shown in the lower side of FIG. 2 (a), a process of changing the coated / formed metal foil 4 to the conductive bump formed metal foil 4a on which the conductive bumps 8 are formed is added. ), Which is different from that shown in FIG.
[0081]
The conductive bump 8 can be formed in a place necessary as a wiring board on the coated / formed metal foil 4 by, for example, screen printing. For that purpose, for example, a conductive paste is prepared by dispersing metal particles (silver, gold, copper, solder, etc.) in a paste-like resin and mixing a volatile solvent. It can be printed on the metal foil 4 by printing and formed into a substantially conical shape as a whole.
[0082]
When the conductive bump-formed metal foil 4a is obtained as described above, next, as shown on the upper side of FIG. 2 (b), one side of both surfaces of the prepreg to be the insulating plate 5 is coated and coated. The resistor 3 and dielectric 2 side of the formed metal foil 4 is arranged on the other side, and the resistor 3, dielectric 2 and conductive bump 8 side of the metal foil 4a on which the conductive bump is formed are opposed to the other side. Let
[0083]
Next, as shown in the center of FIG. 2 (b), the coated / formed metal foil 4, the insulating plate 5, and the conductive bump-formed metal foil 4a are laminated, pressed and heated, and integrated into a double-sided wiring. A plate 6a is obtained. In this double-sided wiring board 6a, the dielectric 2 and the resistor 3 are submerged in the thickness direction of the insulating plate 5 and integrated, and the conductive bumps 8 penetrate the insulating plate 5 and face the opposing metal foil 1. It is in a state of being in direct contact. This is because, as already described, the insulating plate 5 has thermoplasticity and thermosetting property, and the shape of the conductive bumps 8 is essentially a cone.
[0084]
In this double-sided wiring board 6a, the electrical continuity of both wiring layers is made by the conductive bumps 8, and no further process such as through-hole formation is required for the conduction of both wiring layers. Therefore, a higher-density wiring board can be obtained without requiring a space for forming a through hole. Further, since the pressure applied to the dielectric 2 and the resistor 3 is relieved by the conductive bumps 8 in the integration step, changes in the characteristic values of the dielectric 2 and the resistor 3 that occur during the lamination integration There is also an effect that can be suppressed.
[0085]
Following the above, as shown in the lower side of FIG. 2B, the metal foils 1 on both sides are patterned on the pattern 1a required as a wiring board (substantially the same as in the lower case of FIG. 1B). By this patterning, it is possible to obtain a double-sided wiring board 7a on which at least both end electrodes of the dielectric 2 and the resistor 3 are formed. In addition, the resistor 3 may be trimmed by using both end electrodes formed by this patterning as resistance value measuring terminals. This is also as already explained.
[0086]
Although not shown in the drawings, a solder resist or a plating layer including the pattern 1a is formed, a surface mount component is mounted on the pattern 1a, and a semiconductor chip is flip chip mounted by a known method. it can. Further, by etching the metal foil 1 as described above, a spiral inductor can be formed, but the conductive bump 8 described above can be used for the inner terminal in that case.
[0087]
  As described aboveExampleThen, it demonstrated in FIG. 1 (a), FIG.1 (b).ExampleIn the same manner as above, since the dielectric 2 and the resistor 3 are formed on the metal foil 1 in advance by selecting a material from a wide selection range, capacitors and resistors having excellent characteristics are mixed in the same layer. be able to. Moreover, since an organic material is used as the insulating plate 5, the weight can be reduced as compared with ceramics. In order to form a spiral inductor, a conductive paste may be applied in advance on the metal foil 1 in a spiral shape.
[0088]
  3 has been described with reference to FIGS. 1 (a) and 1 (b).ExampleThe double-sided wiring board 7 that can be manufactured by the method described in FIG. 2A and FIG. 2BExampleThe double-sided wiring board 7a which can be manufactured by this is shown as a perspective view. As shown in FIG. 3, on both sides (or one side) of the insulating plate 5, a resistor by the resistor 3, a capacitor by the dielectric 2, and a spiral inductor by the pattern 1a are provided on the wiring boards 7 and 7a. It can be formed as a pre-arranged form. Of course, it is also possible to mount the surface mounting components, semiconductor devices, etc. on both sides of the double-sided wiring board 7a using the wiring pattern 1a as lands, and to make the mounting wiring board as it is.
[0089]
4 (a) and 4 (b) show a double-sided wiring board 7a (FIG. 1 (a) and FIG. 1 (b) or a double-sided wiring board 7a (FIG. 2 (a) and FIG. 2 (b)) manufactured by the process shown in FIG. It is a figure which shows the process performed in order to use 7) as a raw material of a four-layer wiring board. 4A is a cross-sectional view, and FIG. 4B is a perspective view. 5 (a) and 5 (b) show a double-sided wiring board 7a (FIG. 1 (a) and FIG. 1 (b) or a double-sided wiring board 7a (FIG. 2 (a) and FIG. 2 (b)) manufactured by the process shown in FIG. It is a figure which shows the metal foil required when manufacturing a four-layer wiring board using 7), and the process given to it. FIG. 5A is a cross-sectional view, and FIG. 5B is a perspective view. Further, the parts already described in these drawings are denoted by the same reference numerals. The n-layer wiring board is a wiring board having n wiring layers.
[0090]
First, as shown in FIGS. 4A and 4B, since the double-sided wiring board 7a (7) is used as a core wiring board, a required position on one side (a layout as a specific four-layer wiring board). The conductive bump 9 is formed at a position according to the above. The formation of the conductive bump 9 can be performed in substantially the same manner as the formation of the conductive bump 8 already described. Thereby, the wiring board material 71 having the conductive bumps 9 is formed.
[0091]
At the same time, as shown in FIGS. 5A and 5B, the metal foil 1 is prepared for the third wiring layer, and a necessary position on one side (a layout as a specific four-layer wiring board). The conductive bump 9 is formed at a position according to the above. The formation of the conductive bump 9 is the same as described above. Thereby, the metal foil 11 having the conductive bumps 9 is formed.
[0092]
FIG. 6 shows the wiring board material 71 manufactured by the process shown in FIGS. 4A and 4B and the metal foil 11 shown in FIGS. 5A and 5B as materials. It is a figure which shows the process of using and manufacturing a four-layer wiring board. FIG. 7 is a perspective view showing the process shown in FIG. In FIG. 6 and FIG. 7, the parts already described are given the same reference numerals.
[0093]
6 and 7, first, the metal foil 1 is passed through the prepreg to be the insulating plate 51 so as to face the surface of the wiring board material 71 on which the conductive bumps 9 are formed. The sides of the metal foil 11 on which the conductive bumps 9 are formed are arranged so as to face the surface of the wiring board material 71 on which the conductive bumps 9 are not formed, with the prepreg to be the insulating plate 51. Here, the prepreg to be used as the insulating plate 51 may be the same as the prepreg to be used as the insulating plate 5 described above.
[0094]
Next, as shown in each center of FIG. 6 and FIG. 7, the metal foil 1, the insulating plate 51, the wiring board material 71, the insulating plate 51, and the metal foil 11 are stacked and pressurized and heated to be integrated into 4. A layer wiring board 21 is obtained. In the four-layer wiring board 21, the wiring patterns 1 a on both surfaces of the wiring board material 71 are integrated by sinking in the thickness direction of the insulating board 51, and the conductive bumps 9 penetrate the insulating board 51 and face each other. 1 or the pattern 1a is brought into electrical contact. This is because the insulating plate 51 has thermoplasticity and thermosetting properties and the shape of the conductive bump 9 is essentially a cone.
[0095]
In the four-layer wiring board 21, electrical conduction between the outer wiring layer and the inner wiring layer is made by the conductive bumps 9, and a further process such as formation of a through hole is required for conduction between these wiring layers. do not do. Therefore, a higher-density four-layer wiring board can be obtained without requiring a space for forming a through hole. In addition, the fact that the formation of the through hole is unnecessary does not affect the layout of other layers, and the meaning becomes greater as the number of layers increases.
[0096]
Next, as shown in each lower side of FIGS. 6 and 7, the metal foils 1 on both surfaces of the four-layer wiring board 21 are patterned into a pattern 1b necessary as a wiring board. By this patterning, a four-layer wiring board 22 can be obtained. As described above, a well-known method can be used for patterning, and a spiral inductor may be formed by patterning.
[0097]
Although not shown in the drawings, a solder resist or a plating layer including the pattern 1b is formed, a surface mount component is mounted on the pattern 1b, and a semiconductor chip is flip chip mounted by a known method. it can.
[0098]
  AboveExampleThen, a four-layer wiring board using the double-sided wiring board 7a (7) obtained by the manufacturing method described in FIGS. 1A and 1B, 2A and 2B as a core wiring board. Explained to manufacture. Therefore, the four-layer wiring board can be obtained while maintaining the characteristics as the double-sided wiring board 7a (7) already described. In addition, since the insulating plate 51, which is an organic material, is used for multilayering, the multilayer wiring board can be reduced in weight compared to ceramics.
[0099]
In the above description, it has been described that the four-layer wiring board is manufactured using the double-sided wiring board 7a (7). However, the three-layer wiring board can be formed in substantially the same manner. That is, as one method, in the upper diagram of FIG. 6, up to three members (the metal foil 1, the insulating plate 51, and the wiring board material 71) are laminated and pressed and heated to integrate them. For example, a three-layer wiring board can be obtained. Further, as another method, in the upper diagram of FIG. 6, there are three from the bottom (however, in this case, the conductive bump 9 of the wiring board material 71 is unnecessary, so the wiring board material 7a (7) The three layers of the insulating plate 51 and the metal foil 11) are laminated and pressurized and heated and integrated to obtain a three-layer wiring board.
[0100]
Also in such a three-layer wiring board, the characteristics as the double-sided wiring board 7a (7) already described are maintained, and a three-layer circuit is realized.
[0101]
In the above description, the case where passive elements are not formed for the third and fourth wiring layers of the four-layer wiring board and the third wiring layer of the three-layer wiring board has been described. In the figure, instead of the upper metal foil 1, a coated and formed metal foil 4 (used with the passive element forming surface facing downward) shown in FIG. 1 (a) or FIG. 2 (a) is used. Instead of 11, the conductive bump-formed metal foil 4a shown in FIG. 2A may be used to form passive elements in the third and fourth wiring layers.
[0102]
According to these, the third and fourth wiring layers of the four-layer wiring board 22 can be formed in a form in which a resistor by the resistor 3 and a capacitor by the dielectric 2 are provided in advance. Since the resistors and capacitors provided in the third and fourth wiring layers are also formed in advance on the metal foil 1 before lamination, the same advantages as the resistors and capacitors provided in the first and second wiring layers are provided. have. Also, the resistors provided in the third and fourth wiring layers can be trimmed by the pattern 1b. In addition, by applying a spiral conductive paste to the metal foil 1 in advance, an inductor made of the conductive paste can be formed on the third and fourth wiring layers.
[0103]
Furthermore, if the method described above is used repeatedly, it is possible to easily obtain a wiring board having wiring layers exceeding four layers. For example, in the case of a six-layer wiring board, a board in which conductive bumps are formed on one side of the four-layer wiring board 22 may be used instead of the wiring board material 71 in the upper diagram of FIG. By repeating such a process, a multilayered wiring board can be obtained.
[0104]
FIG. 8 is a perspective view showing an example of a four-layer wiring board manufactured by the manufacturing method shown in FIGS. In the four-layer wiring board 22a of this example, a land for mounting the semiconductor device 32 and the surface mounting component is formed by the pattern 1b of the outer wiring layer, and the loop antenna 31 is provided near the outer edge of the four-layer wiring board 22a. It was made to form.
[0105]
Thereby, for example, the semiconductor device 32, the loop antenna 31, and the passive elements (things built in as a wiring board and surface mount components) necessary for an IC card (integrated circuit card) for exchanging information wirelessly are integrated. This can be configured with a four-layer wiring board. The formation of the loop antenna 31 with such a pattern can also be performed with the pattern 1a on the double-sided wiring board 7 (7a) already described in FIG. 1 (b) or FIG. 2 (b).
[0106]
  FIG. 9 illustrates the present invention.oneEmbodimentYet another reference to explainDouble-sided wiring board manufactured by manufacturing methodOneFIG. Components already described are given the same reference numerals.
[0107]
This double-sided wiring board 7b is different from that shown in FIG. 2B in that the conductive bumps 8 penetrating the insulating board 5 are directly used as the conductors of the resistor 3. In order to manufacture a double-sided wiring board with such a configuration, when the metal foil 4a shown in FIG. 2A is formed, the conductive bumps 8 are formed on the resistor 3 of the metal foil 1. What is necessary is just to set the position.
[0108]
And it laminates | stacks as shown in FIG.2 (b), and the metal foil 1 of both surfaces is patterned after that. In this patterning, the metal foil 1 on the side in contact with the resistor 3 can be patterned so as not to contact the resistor 3 at all.
[0109]
  In the resistor having such a configuration, since the conducting wire is not a metal material used for the metal foil 1, a resistor paste to be used as the resistor 3 can be selected without considering compatibility with the metal material. . Here, compatibility refers to, for example, the ease with which chemical and physical changes occur at the interface of the metal foil 1 due to contact between the metal material (for example, copper) and the resistor 3. If the compatibility is poor, corrosion may occur at an early stage. thisExampleThen, since it is not necessary to consider at least compatibility with the metal foil 1, the range of selection of the resistance paste can be further expanded. Therefore, it can contribute to higher accuracy.
[0110]
FIG. 10 is a bottom view as an example of the double-sided wiring board 7b shown in FIG. Parts corresponding to those in FIG. 9 are denoted by the same reference numerals.
[0111]
As shown in FIG. 10, the contact between the resistor 3 and the conductive bump 8 may be plural (3 in the case shown in the figure) at one end. This is because the shape of the resistor 3 changes in length and width depending on the required resistance value, and the size of the conductive bump 8 is usually fixed because it is formed at a time, for example, by printing. It is. By using a plurality of conductive bumps 8, it is possible to lead out the conductive wires according to the size of the resistor 3.
[0112]
11 is a partial cross-sectional view showing another example of the example shown in FIG. Components already described are given the same reference numerals.
[0113]
This double-sided wiring board 7c is the same as that shown in FIG. 9 in that conductive bumps 8a penetrating the insulating board 5 are formed directly on the resistor 3. However, in the case shown in FIG. 11, the conductive bump 8a is used not as a conductor but as a heat conductor for the resistor 3. The conductive bump 8a has a function of conducting heat to the wiring pattern 1c on the back surface side of the resistor 3. A plurality of conductive bumps 8 a may be provided for one resistor 3.
[0114]
In such a resistor having conductive bumps 8a for conducting heat, Joule heat generated due to the resistor is generated on both sides of the wiring board using the conductive bumps 8a and the wiring pattern 1c as heat sinks. It is possible to dissipate efficiently. Therefore, it is possible to increase the power rating as a resistor, thereby improving the degree of freedom of circuit design applied to the wiring board.
[0115]
  12 (a) and 12 (b) show the present invention.oneIt is a partial cross section figure for demonstrating an example of the double-sided wiring board manufactured with the manufacturing method which concerns on embodiment. Here, FIG. 12A shows an intermediate stage to reach the state of FIG. Moreover, the same code | symbol is attached | subjected to the component already demonstrated.
[0116]
The double-sided wiring board 7d is different from those shown in FIGS. 1B and 2B in that the pattern 1a and the conductor 35 formed of a conductor paste are used as both end electrodes of the dielectric 2. Is a point.
[0117]
In order to manufacture a double-sided wiring board having such a configuration, first, as shown in FIG. 12A, after applying and forming the dielectric 2 on the metal foil 1, the conductive material to be used as the conductor 35 is formed. The paste is applied so as to include on the dielectric 2 and also on the metal foil 1. For this application, a method similar to the application of the dielectric paste to be the dielectric 2 can be used. The applied conductive paste is subjected to processing such as predetermined drying. Then, this metal foil 1 is used in place of the coated / formed metal foil 4 on the upper side of FIG. 1B or FIG. Further, by patterning the metal foils 1 on both sides, a double-sided wiring board 7d as shown in FIG. 12B can be obtained (in FIG. 12B, strictly speaking, there are conductive bumps 8). This is applied to the case shown in Fig. 2B, but the presence of the conductive bumps 8 is not essential.
[0118]
In such a structure around the dielectric 2, since the dielectric 2 is sandwiched between the pattern 1 a and the conductor 35 to form a so-called parallel plate type, a capacitor having a higher capacity can be formed. Moreover, all the improvement effects as the passive elements and wiring boards already described are maintained.
[0119]
FIGS. 13A and 13B are partial cross-sectional views for explaining another example with respect to the example shown in FIGS. 12A and 12B. Here, FIG. 13A shows an intermediate stage to the state of FIG. Moreover, the same code | symbol is attached | subjected to the component already demonstrated.
[0120]
This double-sided wiring board 7e is formed by further laminating the parallel plate capacitor structure described above. A capacitor having a higher capacity can be formed by such lamination.
[0121]
Specifically, as shown in FIG. 13A, first, a dielectric 26 is applied and formed on the metal foil 1, and then a conductive paste to be the conductor 36 is applied on the dielectric 26. It is applied so as to extend over the metal foil 1. After this application, a predetermined drying process is performed. Next, a dielectric paste to be used as the dielectric 27 is applied so as to be in contact with the dielectric 26 including the conductor 36. After this application, a predetermined drying process is performed. Next, a conductive paste to be the conductor 38 is applied so as to cover the metal foil 1 so as not to be in contact with the conductor 36 but on the dielectric 27. After this application, a predetermined drying process is performed.
[0122]
Further, a dielectric paste to be the dielectric 28 is applied so as to include the conductor 38 and be in contact with the dielectric 27. After this application, a predetermined drying process is performed. Next, a conductive paste to be used as the conductor 37 is applied so as to include the dielectric 28 and not to contact the conductor 38 and to contact the conductor 36. After this application, a predetermined drying process is performed. The application of the dielectric paste to be the dielectrics 26, 27, and 28 and the application of the conductive paste to be the electrical conductors 36, 37, and 38 are shown in FIGS. 12 (a) and 12 (b), for example. This can be performed in the same manner as in the case of the dielectric 2 and the conductor 35 in the embodiment.
[0123]
Then, this metal foil 1 is used in place of the coated / formed metal foil 4 on the upper side of FIG. 1B or FIG. Further, by patterning the metal foils 1 on both sides, a double-sided wiring board 7e as shown in FIG. 13B can be obtained (in FIG. 13B, strictly speaking, there are conductive bumps 8). This is applied to the case shown in Fig. 2B, but the presence of the conductive bumps 8 is not essential. Here, the patterning of the metal foil 1 is performed so that there is a pattern that occupies most of the dielectric 26 and in contact with the conductor 38 as one electrode, and the conductor as the other electrode. This is performed so that there is a pattern having electrical continuity with 36 and 37.
[0124]
Such a laminated capacitor can be further increased in capacity by further carrying out similar lamination. Moreover, all the improvement effects as the passive elements and wiring boards already described are maintained.
[0125]
Note that the examples of FIGS. 9 to 13B described above describe the case of a double-sided wiring board, but a four-layer wiring board as shown in FIGS. 6 and 7 (or the three-layer already described). It is obvious that the passive elements described above can be formed also on the outer wiring layer in the wiring board). The same applies to a multilayer wiring board having more than four layers.
[0138]
【The invention's effect】
  As detailed above, according to the present invention,, InvitationElectrical paceToIs applied or formed on the metal foil. So these pacesToProcessing such as heat treatment (for example, drying, baking, thermosetting, etc.) can be performed regardless of the heat-resistant temperature of the insulating plate. And, for example, this is heat treatedDielectricSince the metal foil is laminated with the insulating plate, a wiring board provided with a passive element having excellent characteristics can be obtained.
[Brief description of the drawings]
FIG. 1 shows an embodiment of the present invention.To help explainThe figure which shows the process which manufactures a double-sided wiring board with a manufacturing method.
FIG. 2 of the present inventiononeEmbodimentAnother useful reference in explainingThe figure which shows the process which manufactures a double-sided wiring board with a manufacturing method.
3 is a perspective view showing an example of a double-sided wiring board manufactured by the process shown in FIG. 1 or FIG. 2. FIG.
4 is a diagram showing a process performed for using a double-sided wiring board manufactured by the process shown in FIG. 1 or FIG. 2 as a material for a three-layer wiring board or a four-layer wiring board; FIG.
FIG. 5 is a diagram showing a metal foil and a process applied thereto when manufacturing a three-layer wiring board or a four-layer wiring board using the double-sided wiring board manufactured by the process shown in FIG. 1 or FIG.
6 is a diagram showing a process for manufacturing a four-layer wiring board using the wiring board material manufactured by the process shown in FIG. 4 and the metal foil shown in FIG. 5;
7 is a perspective view showing the process shown in FIG. 6. FIG.
8 is a perspective view showing a four-layer wiring board formed by the manufacturing method shown in FIG. 6 (FIG. 7) and having a loop antenna on the outer layer of the wiring.
FIG. 9 shows the present invention.oneEmbodimentYet another reference to explainDouble-sided wiring board manufactured by manufacturing methodOneFIG.
10 is a bottom view of the double-sided wiring board shown in FIG. 9. FIG.
FIG. 11 is a partial cross-sectional view showing another example of the example shown in FIG. 9;
FIG. 12 shows the present invention.oneThe partial cross section figure for demonstrating an example of the double-sided wiring board manufactured with the manufacturing method which concerns on embodiment.
13 is a partial cross-sectional view for explaining another example with respect to the example shown in FIG. 12;
FIG. 14 is a diagram for explaining the disorder of the shape at the edge of the dielectric / resistor / conductor formed on the metal foil and the improvement thereof.
[Explanation of symbols]
  DESCRIPTION OF SYMBOLS 1 ... Metal foil 1a, 1b, 1c ... Pattern 2 ... Dielectric body 3 ... Resistor 4 ... Metal foil with application | coating and formation 4a ... Metal foil with conductive bump formation 5 ... Insulation board 6 ... Double-sided wiring board 6a ... Double-sided wiring board 7 ... Double-sided wiring board 7a ... Double-sided wiring board 7b, 7c, 7d, 7e ... Double-sided wiring board 8 ... Conductive bump 8a ... Conductive vane9... Conductive van1DESCRIPTION OF SYMBOLS 1 ... Metal foil which has conductive bump 21 ... Four-layer wiring board 22 ... Four-layer wiring board 22a ... Four-layer wiring board 26, 27, 28 ... Dielectric 30 ... End of resistor 31 ... Loop antenna 32 ... Semiconductor device 35 ... Conductor 36, 37, 38 ... Conductor 51 ... Insulating plate 71 ... Wiring board material

Claims (4)

Applying a dielectric paste to at least the first surface of the second metal foil of first and second metal foils each having a first surface and a second surface;
Applying a conductive paste so as to include on the applied dielectric paste and also on the first surface to which the dielectric paste is applied;
An insulating plate having thermoplasticity and thermosetting property is arranged opposite to the first surface of the first metal foil, and the surface of the insulating plate is different from the surface facing the first metal foil. Disposing the first surface of the second metal foil oppositely,
A step of forming a double-sided wiring board by laminating and pressing and laminating the first metal foil, the insulating plate, and the second metal foil, which are arranged, to form a double-sided wiring board;
And a step of patterning at least the second metal foil of the formed double-sided wiring board. A method of manufacturing a wiring board provided with passive elements. Applying a dielectric paste to at least the first surface of the second metal foil of first and second metal foils each having a first surface and a second surface;
Applying a first conductive paste so as to include on the applied dielectric paste and also on the first surface to which the dielectric paste is applied;
A step of applying the second dielectric paste so as to include the first conductive upper paste which is the coating,
The second dielectric paste is applied to the first dielectric paste so as not to come into contact with the first conductive paste. The second dielectric paste extends over the first surface to which the second dielectric paste is applied. Applying a conductive paste of
An insulating plate having thermoplasticity and thermosetting property is arranged opposite to the first surface of the first metal foil, and the surface of the insulating plate is different from the surface facing the first metal foil. Disposing the first surface of the second metal foil oppositely,
A step of forming a double-sided wiring board by laminating and pressing and laminating the first metal foil, the insulating plate, and the second metal foil, which are arranged, to form a double-sided wiring board;
And a step of patterning at least the second metal foil of the formed double-sided wiring board. A method of manufacturing a wiring board provided with passive elements. An insulating plate having a first surface and a second surface;
A layered conductor provided by sinking in the thickness direction of the insulating plate on the second surface of the insulating plate;
A layered dielectric provided in contact with a part of the upper surface of the layered conductor and sinking in the thickness direction of the insulating plate;
Wherein provided on the second surface of the insulating plate, characterized by comprising a wiring layer having a separate connection to the layered conductor and the layered dielectric, the wiring board having a passive element. A second layered dielectric provided below the bottom surface of the layered conductor;
The passive element according to claim 3 , further comprising: a second conductor provided under the lower surface of the second layered dielectric and connected to the wiring layer. Wiring board.

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