JP5318393B2 - Semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiring board that satisfies characteristics required for a wiring board such as strength, low thermal expansion coefficient, or the like by microfabricating the arrangement pitch of conductive through holes formed in the wiring board. <P>SOLUTION: The method of manufacturing the wiring substrate includes: a step of arranging a carbon fiber 5a so that a position where a conductive through hole 19 passes through may be a vacancy 6, thermally crimping prepregs 10a, 10b and 10c that the carbon fiber 5a is impregnated with a resin 11, and forming a core 10; a step of forming a through hole 13 passing the inside of the vacancy 6 at a position where the vacancy 6 is formed in the core 10; and a step of forming a conductive layer 14 on the inside surface of the through hole 13, forming the conductive through hole 19 in a manner not to be interfered with the carbon fiber 5a and completing a core substrate 20. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a wiring board and a manufacturing method thereof, and more particularly to a wiring board including a core substrate, a manufacturing method of the wiring board, a semiconductor device using the wiring board, and a prepreg used in the wiring board.

  As a wiring board on which a semiconductor element is mounted, there is a product having a core substrate made of carbon fiber reinforced plastic (CFRP). The core substrate provided with this carbon fiber reinforced plastic has a low coefficient of thermal expansion compared to a core substrate made of a conventional glass epoxy substrate, and the wiring substrate using this core substrate matches the thermal expansion coefficient with the semiconductor element. This is useful in avoiding thermal stress generated between the semiconductor element and the wiring board.

  The wiring board is formed by laminating wiring layers on both sides of the core board, and a conductive through hole PTH (Plated through hole) is formed on the core board for electrical connection with the wiring layer laminated on both sides of the core board. The The conductive through hole is formed by forming a through hole in the substrate and forming a conductive portion (plating layer) on the inner wall surface of the through hole by plating.

By the way, in the case of a core substrate having a conductive core portion such as a carbon fiber reinforced plastic, simply forming a through hole in the substrate and plating the inner wall surface of the through hole results in a conduction through hole and a core portion. Are electrically short-circuited. For this reason, when a conductive through hole is formed in a core substrate having a conductive core portion, a hole having a diameter larger than that of the conductive through hole is formed in the core substrate, and the insulating resin is formed in the lower hole. After filling, the conductive through hole is penetrated into the lower hole so that the conductive through hole and the core portion are not electrically short-circuited (see Patent Documents 1 and 2).
JP 2003-218287 A Table 2004/064467

However, in the arrangement in which a through hole is made in the core substrate and the through hole is penetrated into the under hole, the diameter of the lower hole is larger than that of the through through hole. Thus, the arrangement interval of the conductive through holes is widened, and it is restricted that the conductive through holes are arranged at high density.
In addition, when an insulating resin is filled in the lower hole, the core substrate acts so as to increase the thermal expansion coefficient, and in the case of a wiring substrate having a carbon fiber in the core portion, it is formed with a low thermal expansion coefficient. The advantage of the core substrate is hindered.

  The present invention has been made to solve these problems, and can reduce the pitch of conductive through holes formed in a wiring board, and can provide characteristics such as strength and coefficient of thermal expansion required for a core board. It is an object of the present invention to provide a satisfactory wiring board, a manufacturing method thereof, a semiconductor device, and a prepreg used for the wiring board.

The present invention has the following configuration in order to achieve the above object.
That is, as a method of manufacturing a wiring board, a step is performed in which fibers are arranged so that a position where a conductive through hole passes is vacant, and a prepreg formed by impregnation with a resin is thermocompression bonded to form a core portion; Forming a through-hole that passes through the inside of the vacancy at a position that becomes the vacancy of the core portion, and forming a conductive layer on the inner surface of the through-hole to form a conductive through-hole in an arrangement that does not interfere with the fiber. a step of a core substrate Te, possess a cutting step of cutting the large-sized wiring board into pieces, and in the step of forming the core portion, said fibers, a composite of carbon fibers and a non-conductive fibers Using a prepreg formed as a woven fabric and having vacancies through which the conductive through-holes are formed in the woven fabric, and in the cutting step, cutting at a position where the non-conductive fibers are arranged I, wherein the exposing the non-conductive fibers in the cut end face.

The wiring board includes a core board, a wiring layer provided on both surfaces of the core board, and a conductive through hole provided in the core board for electrically connecting the wiring layers. The core part constituting the core substrate is formed by thermocompression bonding of a prepreg formed by impregnating a resin into a fiber, and the conductive through hole is provided without interfering with the fiber of the core part , The fiber is formed as a woven fabric composed of a composite of carbon fiber and non-conductive fiber, and a vacancy through which the conductive through hole passes is formed in the woven fabric, and the non-conductive fiber is disposed. It cut | disconnects in a position and this nonelectroconductive fiber is exposed to the cut end surface, It is characterized by the above-mentioned. The wiring board can also be used as an interposer.

  Further, a semiconductor device can be provided by mounting a semiconductor element on the wiring board.

Also, a prepreg constituting a core portion constituting a core substrate of a wiring board, containing a fiber having a lower thermal expansion coefficient than copper, and the fiber interferes with a conductive through hole formed in the core substrate. Those provided in an arrangement not to be used are effectively used.
Further, the fiber is formed as a carbon fiber woven fabric, and the carbon fiber woven fabric is formed with a vacancy through which the conductive through hole passes, so that an electrical short circuit with the conductive through hole is avoided, and a low heat There is an advantage that it is configured as a core substrate having an expansion coefficient. In addition, it is preferable that the fiber is formed as a woven fabric in which a carbon fiber and a non-conductive fiber are combined, and a vacancy through which the conductive through hole passes is formed in the woven fabric.

  In the wiring board and the manufacturing method thereof according to the present invention, the fibers contained in the prepreg forming the core portion of the core substrate are arranged so as not to interfere with the position through which the conductive through hole of the core substrate passes. Regardless of the arrangement of the conductive through holes, the conductive through holes can be formed, and the conductive through holes can be arranged at a fine pitch. Further, by selecting the fiber to be included in the prepreg, the core substrate can be provided with characteristics such as required strength.

(Method for manufacturing a wiring board)
Hereinafter, an embodiment of a method for manufacturing a wiring board according to the present invention will be described.
In the method for manufacturing a wiring substrate according to the present embodiment, a core substrate having a core portion made of carbon fiber reinforced plastic is used.
FIG. 1 shows a process until a core substrate 20 having a core portion 10 made of carbon fiber reinforced plastic is formed.

FIG. 1 (a) shows a prepreg 10a, 10b, 10c containing carbon fibers, and a prepreg 12 having electrical insulation containing a filler such as alumina, silica, etc. for adjusting the thermal expansion coefficient. In order to perform the pressure bonding, a state where the alignment is made is shown.
In the present embodiment, the core portion 10 is formed by stacking three prepregs 10a, 10b, and 10c, but the number of prepregs constituting the core portion 10 depends on the thickness of the wiring substrate, the strength as the core substrate, or the like. The request can be selected as appropriate.

The most characteristic configuration in the method for manufacturing a wiring board according to the present embodiment is the configuration of prepregs 10 a, 10 b, and 10 c containing carbon fibers that constitute the core portion 10. That is, the prepregs 10a, 10b, and 10c are formed as a woven fabric using long carbon fibers, and the carbon fiber woven fabric is impregnated with a resin such as an epoxy resin to form a semi-cured state having adhesiveness. .
A structural feature of the prepregs 10a, 10b, and 10c is the weaving method. That is, in a normal woven fabric, the fibers are uniformly woven in a plane, but the carbon fiber woven fabric used in the prepregs 10a, 10b, and 10c used in this embodiment is a conductive through hole and a carbon fiber formed in the core substrate. In order not to interfere with 5a, it is woven so that the position through which the conductive through hole passes becomes an empty portion.

  In FIG. 2, the state which looked at the carbon fiber woven fabric 5 used for prepreg 10a, 10b, 10c from the plane direction is shown. The carbon fiber woven fabric 5 is formed by weaving the carbon fibers 5a in a plain weave shape. However, as a weaving method for separating the plain weave portions at regular intervals, empty portions (referred to as vacancies in this specification) are formed at predetermined intervals. I try to do it. In this vacancy 6, a conductive through hole passes when the core substrate is formed. That is, the carbon fiber woven fabric 5 is woven so as to form vacancies 6 in advance in accordance with the arrangement of the conductive through holes formed in the core substrate.

Although the planar arrangement of the conductive through holes formed in the core substrate differs depending on the product, the conductive through holes provided in the core substrate are usually arranged at predetermined intervals in the vertical and horizontal directions. In this way, when the conductive through holes are arranged at predetermined intervals, the carbon fiber woven fabric 5 can be formed so that the vacancy 6 is formed in accordance with the planar arrangement of the conductive through holes. is there.
In addition, when forming the carbon fiber woven fabric 5, it is possible to adjust the vertical and horizontal dimensions of the vacancy 6 through which the conductive through hole passes while matching the arrangement of the conductive through hole.

The carbon fiber single wire has a diameter of about several μm. Therefore, it is possible to form a carbon fiber woven fabric 5 as shown in FIG. 2 by weaving a single wire of carbon fiber, or to use a yarn obtained by twisting a plurality of single wires of carbon fiber. Can also be formed. In the case of carbon fiber twisted yarn, the diameter is about several tens of μm.
The arrangement pitch of the conductive through holes formed in the core substrate varies depending on the product. For example, if the conductive through holes are arranged at an arrangement pitch of about 400 μm used in a general semiconductor element mounting substrate, it is several tens of μm. It is easy to form the carbon fiber woven fabric 5 in an arrangement for forming the void 6 using a twisted yarn of a degree.

  The carbon fiber woven fabric 5 shown in FIG. 2 is woven so that the carbon fibers 5a intersect at right angles. However, the crossing angle of the carbon fibers 5a is other than right angles, for example, intersects at an angle of 120 °. It is also possible to form the carbon fiber woven fabric 5 in which the voids 6 are formed. Further, the planar shape of the vacancy 6 formed in the carbon phiffer woven fabric 5 can be woven into a rectangle, a rhombus, a hexagon, an octagon, or the like other than a square.

  Further, the carbon fiber woven fabric 5 shown in FIG. 2 is an example in which the vacancies 6 are aligned at regular intervals in the vertical and horizontal directions. However, the conductive through holes formed in the core substrate are not arranged in a uniform manner, but in a plane. It is also conceivable that the carbon fiber woven fabric 5 is formed so as to form vacancies 6 in accordance with the planar arrangement of these conduction through holes. The present invention is not limited to the wiring board in which the conductive through holes are arranged uniformly and is applicable to the case where the conductive through holes are arranged unevenly.

A prepreg is obtained by impregnating the carbon fiber woven fabric 5 with a resin. This prepreg is obtained by impregnating the carbon fiber 5a portion of the carbon fiber woven fabric 5 with resin and filling the vacant space 6 with the resin 11. In addition, when the vacancy 6 is greatly opened, the vacancy 6 may not be filled with resin.
FIG. 1A shows a state in which the prepregs 10a, 10b, and 10c thus obtained are aligned. When aligning a plurality of prepregs in such a manner, the alignment is performed so that the plane positions of the vacancies 6 of the carbon fiber woven fabric 5 coincide.

  In the manufacturing process, a large carbon fiber woven fabric 5 is prepared, and the carbon fiber woven fabric 5 is impregnated with a resin such as an epoxy resin to form large prepregs 10a, 10b, 10c, and large prepregs 10a, 10b. 10c is used to form the core substrate. FIG. 1 is an enlarged view of a part of large prepregs 10a, 10b, and 10c for taking a large number of pieces.

  FIG. 1B shows a state in which the prepregs 10a, 10b, 10c, and 12 are thermocompression bonded to form a flat plate. The core portion 10 formed by integrating the prepregs 10a, 10b, and 10c is disposed on the inner layer of the insulating layer 12a made of the prepreg 12. The core portion 10 includes a region including the carbon fiber 5 a and a region where the carbon fiber woven fabric 5 is vacant 6. A region including the carbon fiber 5a is a region having conductivity, and a region having a vacancy 6 is a region filled with the resin 11 and a region having electrical insulation. When the vacant space 6 of the carbon fiber woven fabric 5 is not filled with the resin 11 in the prepreg state, the vacant space 6 is filled with the resin from the prepreg 12 by thermocompression bonding.

  After the core portion 10 is integrally formed, the through hole 13 is formed in accordance with the position where the resin 11 (12) of the core portion 10 is filled, in other words, the position where the carbon fiber woven fabric 5 is the vacant 6 (see FIG. 1 (c)). The through hole 13 is formed to have a smaller diameter than the void 6 formed in the carbon fiber woven fabric 5. As a result, the resin 11 is exposed on the inner surface of the through hole 13. The through hole 13 is formed by drilling, for example.

  In FIG. 1 (d), in order to form a conductive through hole, electroless copper plating and electrolytic copper plating are applied to the core portion 10, and the conductor layer 14 is formed on the inner side surface of the through hole 13 and the surface of the core portion 10. State. Since the inner surface of the through-hole 13 is covered with the resin 11 and the insulating layer 12a, the conductor layer 14 and the core portion 10 have conductivity even when the conductor layer 14 is formed on the inner surface of the through-hole 13. The region containing the carbon fiber 5a is not electrically short-circuited.

FIG. 1E shows a state in which the conductor layer 16 is formed on both surfaces of the core portion 10 after the through hole 13 is filled with the resin 15. The conductor layer 16 can be formed by plating.
FIG. 1F shows a state in which the conductor layers 16 and 14 are etched into a predetermined pattern to form a wiring pattern 18 on the surface of the substrate and a core substrate 20 is formed. The conductor layer 14 formed on the inner surface of the through hole 13 becomes a conductive through hole 19 that electrically connects the wiring patterns formed on both surfaces of the core substrate 20.
The conductive through hole 19 is disposed through the through hole 13 formed in the core portion 10, and the inner side surface of the through hole 13 is covered with the electrically insulating resin 11. It is possible to prevent an electrical short circuit with 10 conductor portions, that is, the region containing the carbon fiber 5a.

  As described above, in the method for manufacturing the core substrate of the present embodiment, the conductive through hole is formed in the core substrate 20 by providing the void 6 that allows the conductive through hole 19 to pass through the carbon fiber woven fabric 5 constituting the core portion 10. When 19 is provided, it is avoided that the conduction through hole 19 is electrically connected to the carbon fiber woven fabric 5, and the conduction through hole 19 is prevented from being electrically short-circuited to the core portion 10.

Further, the core portion 10 of the core substrate 20 is only provided with the through hole 13 for forming the conductive through hole 19, and there is no need to form a pilot hole through which the conductive through hole passes unlike the conventional core substrate. Thereby, the arrangement pitch of the conductive through holes 19 formed in the core substrate 20 can be made narrower than that of the conventional core substrate, and the conductive through holes 19 can be formed at a higher density.
Moreover, since the through-hole 13 formed in the core part 10 has a smaller diameter than the conventional one, even if the resin 15 is filled in the through-hole 13, the resin is less than the conventional case where the resin is filled in the lower hole. It is possible to effectively suppress an increase in the thermal expansion coefficient of the core substrate.

(Wiring board)
FIG. 3 shows a state where the wiring board 30 is formed by laminating the wiring layers 22 on both surfaces of the core board 20. The wiring layer 22 is formed by electrically connecting the wiring pattern 26 between the insulating layers 25 via the vias 24. The wiring patterns 26 formed on the wiring layers 22 on both surfaces of the wiring substrate 30 are electrically connected through the conductive through holes 19 formed in the core substrate 20.
The wiring layer 22 can be formed by, for example, a build-up method. Pads 27 to which the semiconductor elements are connected are formed on one surface of the wiring board 30 on which the semiconductor elements are mounted. A land 29 to which an external connection terminal such as a solder ball is joined is formed on the other surface of the wiring board 30.

FIG. 4 shows a state in which the semiconductor device 50 in which the semiconductor element 40 is mounted on the wiring substrate 30 is mounted on the mounting substrate 60. The semiconductor element 40 is mounted on the wiring board 30 by flip chip connection. The semiconductor device 50 is mounted on the mounting substrate 60 with solder balls 62 bonded to the lands 29.
The semiconductor element 40 and the mounting substrate 60 are electrically connected through the conductive through hole 19 formed in the wiring substrate 30, the wiring patterns 18 and 26 formed in the wiring layer 22, the via 24, and the like.

  As described above, the conductive through hole 19 formed in the wiring substrate 30 is formed by opening the through hole 13 for forming the conductive through hole 19 in the core substrate 20. It can be arranged at a fine pitch such as 400 μm pitch, and is suitable for mounting a semiconductor element in which electrodes are arranged at a fine pitch.

  In addition, the wiring board 30 and the semiconductor device 50 according to the present embodiment can match the thermal expansion coefficient with the semiconductor element 40 by using the carbon fiber woven fabric 5 having a low thermal expansion coefficient for the core board 20. The thermal expansion coefficient of the carbon fiber is about 1 ppm / ° C., and the thermal expansion coefficient of silicon constituting the semiconductor element 40 is about 3 ppm / ° C. Therefore, the overall thermal expansion coefficient of the wiring board 30 can be reduced by mixing filler in the prepreg including the carbon fiber constituting the core portion 10 or adjusting the thermal expansion coefficient of the insulating layer 25 used for the wiring layer 22. The thermal expansion coefficient of the semiconductor element 40 can be matched.

  Thus, by matching the thermal expansion coefficient of the wiring board 30 with the thermal expansion coefficient of the semiconductor element 40, heat generated between the semiconductor element 40 and the wiring board 30 during the heat treatment process in the manufacturing process or during the mounting operation. The stress can be relieved and the wiring board 30 and the semiconductor device 50 can be provided with high reliability.

In the above embodiment, the core portion 10 of the core substrate 20 is formed by using the carbon fiber woven fabric 5, but the woven fabric constituting the core portion 10 is formed as a composite weave of the carbon fiber 5a and other fibers. You can also.
In the above embodiment, the semiconductor device 50 in which the semiconductor element 40 is mounted on the wiring board 30 is mounted on the mounting board 60. However, the wiring board 30 is used as an interposer, and the wiring board 30 is interposed on the circuit board. Thus, the semiconductor device on which the semiconductor element 40 is mounted may be mounted on the mounting substrate 60.

  FIG. 5 shows a plan view of a woven fabric 8 that is a composite weave of carbon fibers 5a and aramid fibers 7 in the carbon fiber woven fabric 5 shown in FIG. This woven fabric 8 is also woven so as to form vacancies 6 in accordance with the arrangement of the conductive through holes 19 formed in the core substrate 20. The aramid fiber 7 has a thermal expansion coefficient of 2-3 ppm / ° C., which is lower than that of silicon, and is suitably used as a fiber constituting the woven fabric 8. Of course, resin fibers other than aramid fibers, non-conductive fibers such as ceramic fibers, or conductive fibers can be used.

  Also when this woven fabric 8 is used, the woven fabric 8 is immersed in a resin such as an epoxy resin, and the woven fabric 8 is impregnated with the resin to form a prepreg. The method of forming the core substrate using the prepreg formed using the woven fabric 8 is exactly the same as the method described above.

According to the method using the woven fabric 8 in which the fiber such as the aramid fiber 7 and the carbon fiber 5a are woven together, the coefficient of thermal expansion of the core portion 10 is adjusted by adjusting the composition ratio between the carbon fiber 5a and the aramid fiber 7. There is an advantage that it can be adjusted.
Further, after the wiring board is formed, when the large-sized wiring board is cut into individual pieces, as shown in FIG. 5, the position where the aramid fibers 7 are arranged is a cutting position (for example, AA in the figure). The aramid fiber 7 is exposed on the cut end surface of the wiring board by cutting as the line position), and the range in which the carbon fiber 5a is exposed is suppressed, and the carbon fiber 5a is peeled off from the outer surface of the separated wiring board. And the problem that the carbon fiber 5a exposed on the side surface of the wiring board contacts other electronic components and is electrically short-circuited can be avoided.

  In addition, when using the woven fabric which combined carbon fiber and another fiber, the fiber used combining with a carbon fiber is not restricted to one type of fiber. A carbon fiber and two or more kinds of other fibers can be combined to form a woven fabric, or another conductive fiber can be used instead of the carbon fiber.

Moreover, in the said embodiment, although the carbon fiber woven fabric 5 was used for the core part 10, not only a woven fabric but a nonwoven fabric can also be used.
Further, the present invention can also be applied to the case where a conductive fiber other than carbon fiber or a non-conductive fiber such as a ceramic fiber or a ceramic filler is used as the core portion constituting the core substrate 20. That is, the core substrate uses a certain strength required as a holding body for the wiring board and copper or a fiber having a lower thermal expansion coefficient than that of the semiconductor element as a fiber that does not greatly deviate from the semiconductor element mounted on the wiring board. It is done. Therefore, when these materials (fibers) are used, the fiber is arranged in an arrangement that does not interfere with the passing position of the conductive through-hole, in order to adjust the strength or thermal expansion coefficient of the core substrate. The core substrate or the wiring substrate can be formed in exactly the same form as the embodiment.
(Appendix 1)
The step of forming the core part by thermocompression bonding the prepreg formed by impregnating the resin with the fibers arranged so that the position where the conductive through hole passes becomes vacant, and the position of the core part at the vacant position A step of forming a through hole that passes through the inside of the vacancy, and a step of forming a conductive layer on the inner surface of the through hole and forming a conductive through hole in an arrangement that does not interfere with the fibers to form a core substrate A method for manufacturing a wiring board.
(Appendix 2)
The method of manufacturing a wiring board according to claim 1, further comprising a step of laminating wiring layers on both surfaces of the core substrate.
(Appendix 3)
The method for manufacturing a wiring board according to claim 1 or 2, wherein, in the step of forming the core portion, a plurality of prepregs are thermocompression-bonded with the vacant positions aligned with each other.
(Appendix 4)
In the step of forming the core portion, the fiber is formed as a carbon fiber woven fabric, and the carbon fiber woven fabric uses a prepreg in which a vacancy through which the conduction through hole passes is formed. The method for manufacturing a wiring board according to any one of claims 3 to 4.
(Appendix 5)
In the step of forming the core portion, the fiber is formed as a woven fabric in which carbon fibers and non-conductive fibers are combined, and a prepreg in which a vacancy through which the conductive through hole passes is formed in the woven fabric is used. The manufacturing method of the wiring board as described in any one of the additional remarks 1-3 characterized by performing.
(Appendix 6)
A core comprising the core substrate, a wiring layer provided on both surfaces of the core substrate, and a conductive through hole provided in the core substrate for electrically connecting the wiring layers, and constituting the core substrate The wiring board is characterized in that the portion is formed by thermocompression bonding of a prepreg formed by impregnating a resin into a fiber, and the conductive through hole is provided without interfering with the fiber of the core portion.
(Appendix 7)
The wiring board according to appendix 6, wherein the fiber has a lower coefficient of thermal expansion than the semiconductor element.
(Appendix 8)
The wiring board according to appendix 7, wherein the fiber is formed as a carbon fiber woven fabric, and a vacancy through which the conduction through hole passes is formed in the carbon fiber woven fabric.
(Appendix 9)
The fiber is formed as a woven fabric composed of a composite of carbon fiber and non-conductive fiber,
The wiring board according to appendix 6, wherein a vacancy through which the conductive through hole passes is formed in the woven fabric.
(Appendix 10)
The wiring board according to appendix 9, wherein the non-conductive fibers are aramid fibers.
(Appendix 11)
A core comprising the core substrate, a wiring layer provided on both surfaces of the core substrate, and a conductive through hole provided in the core substrate for electrically connecting the wiring layers, and constituting the core substrate The part is formed by thermocompression bonding of a prepreg formed by impregnating a resin into a fiber, and the conductive through hole is mounted on a wiring board provided without interfering with the fiber of the core part. A semiconductor device in which a semiconductor element is mounted using a wiring board as an interposer.
(Appendix 12)
The semiconductor device according to claim 11, wherein the fiber is formed as a carbon fiber woven fabric, and a vacancy through which the conduction through hole passes is formed in the carbon fiber woven fabric.
(Appendix 13)
A prepreg constituting a core portion of a core substrate, containing fibers having a thermal expansion coefficient lower than that of copper, and the fibers are provided in an arrangement that does not interfere with conductive through holes formed in the core substrate. A prepreg characterized by that.
(Appendix 14)
The prepreg according to appendix 13, wherein the fiber is formed as a carbon fiber woven fabric, and a vacancy through which the conductive through hole passes is formed in the carbon fiber woven fabric.
(Appendix 15)
15. The prepreg according to appendix 14, wherein the fiber is formed as a woven fabric in which a carbon fiber and a non-conductive fiber are combined, and a vacancy through which the conductive through hole passes is formed in the woven fabric.

It is sectional drawing which shows the manufacturing process of a core board | substrate. It is a top view which shows arrangement | positioning of a carbon fiber woven fabric and a conduction | electrical_connection through hole. It is sectional drawing of a wiring board. It is sectional drawing of the state which mounted the semiconductor device. It is a top view which shows the example of the woven fabric which comprises a core part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 Carbon fiber woven fabric 5a Carbon fiber 6 Void 7 Aramid fiber 8 Woven fabric 10 Core part 10a, 10b, 10c Prepreg 11 Resin 13 Through-hole 18, 26 Wiring pattern 19 Conductive through hole 20 Core substrate 22 Wiring layer 24 Via 27 Pad 29 Land 30 Wiring board 40 Semiconductor element 50 Semiconductor device 60 Mounting board

Claims (1)

A core comprising the core substrate, a wiring layer provided on both surfaces of the core substrate, and a conductive through hole provided in the core substrate for electrically connecting the wiring layers, and constituting the core substrate The part is formed by thermocompression bonding of a prepreg formed by impregnating a resin into a fiber, and the semiconductor element is mounted on a wiring board in which the conductive through hole is provided without interfering with the fiber of the core part. ,
The fiber is formed as a woven fabric that is a composite of carbon fiber and non-conductive fiber, and in the woven fabric, a vacancy through which the conductive through hole passes is formed,
The wiring board is cut at a position where the non-conductive fibers are disposed, and the non-conductive fibers are exposed on the cut end face,
A semiconductor device characterized in that a coefficient of thermal expansion of the wiring board as a whole is matched with a coefficient of thermal expansion of the semiconductor element by adjusting a composition ratio between the carbon fiber and the non-conductive fiber.

Images