JP2007096001A - Manufacturing method of multi-layered wiring substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the manufacturing method of multi-layered wiring substrate wherein a substrate and a metal plate are pressurized uniformly upon manufacturing the multi-layered wiring substrate through hot press molding of the substrate and the metal plate. <P>SOLUTION: In the manufacturing method of the multi-layered wiring substrate, the configuration of a contacting surface between the substrate and the metal plate is substantially same as that between the metal plate and a cushion member. In this case, a pressure is applied on only a part where the metal plate and the substrate exist in the pressurizing direction of the metal plate whereby there is no deflection of the metal plate. According to this method, the substrate and the metal plate can be pressurized uniformly through the cushion member and the metal plate. Accordingly, the generation of faulty connection or void can be prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a multilayer wiring board formed by sandwiching a substrate on which wiring is formed of a conductor with a metal plate.

  Conventionally, as a method of manufacturing a multilayer wiring board, a plurality of boards are stacked, a pressure-sensitive body in which a metal plate is superimposed on the outside is sandwiched between a pair of metal plates, and heat-pressure molding is performed via the metal plate. There was a method (for example, refer patent document 1). At this time, a cushion material having an outer dimension smaller than that of the metal plate is used between the pressed body and the metal plate.

JP 9-29773 A

  However, when the shape of the cushion material is larger than the shape of the contact surface between the metal plate and the substrate, the shape of the contact surface between the cushion material and the metal plate is more than the shape of the contact surface between the pressed body and the cushion material. Becomes larger. Therefore, the end portion of the metal plate having no pressure object in the pressing direction is also pressed. Therefore, the metal plate is bent, and the pressure applied to the metal plate and the substrate, which are to be pressed, becomes non-uniform. For this reason, connection failure and voids are caused.

  Therefore, in view of the above circumstances, the present invention provides a method for manufacturing a multilayer wiring board that uniformly pressurizes the board and the metal plate when the substrate and the metal plate are heated and pressed to produce a multilayer wiring board. For the purpose.

  In order to achieve the above object, a method for manufacturing a multilayer wiring board according to the present invention is a method for manufacturing a multilayer wiring board in which a substrate is sandwiched between metal plates, wherein the substrate sandwiched between the metal plates is a first. A first step sandwiched between the metal plate and the second metal plate, and opposed to a surface sandwiching the substrate and the metal plate among the two opposing surfaces of the first metal plate and the second metal plate A second step of disposing a cushion material on each of the surfaces to be performed, and a third step of heat-press molding the metal plate and the substrate via the first metal plate, the second metal plate, and the cushion material. And the shape of the contact surfaces of the first metal plate, the second metal plate and the cushion material is substantially the same as the shape of the contact surface of the substrate and the metal plate. It is characterized by .

  In the method for manufacturing a multilayer wiring board of the present invention, the shape of the contact surface between the substrate and the metal plate and the shape of the contact surface between the metal plate and the cushion material are substantially the same. That is, since the pressure is applied only to the portion where the metal plate and the substrate are present in the pressing direction of the metal plate, there is no bending of the metal plate. Therefore, the substrate and the metal plate can be uniformly pressurized through the cushion material and the metal plate. Therefore, it is possible to prevent poor connection and voids.

  Further, in the method for manufacturing a multilayer wiring board according to the present invention, the first metal plate and the second metal plate have a shape of a contact surface between the substrate and the metal plate on a surface in contact with the cushion material. It has the convex part which has the main surface of substantially the same shape, It is characterized by the above-mentioned. Since the pressure is not applied to the portion where the cushion material and the metal plate do not contact, the metal plate does not bend. Therefore, the substrate and the metal plate can be uniformly pressurized through the cushion material and the metal plate.

  Furthermore, in the method for manufacturing a multilayer wiring board according to the present invention, the surface of the first metal plate and the second metal plate contacting the cushion material is substantially the same as the shape of the contact surface between the substrate and the metal plate. It has the same shape. Thereby, since there is no portion in which the metal plate and the substrate do not exist in the pressing direction of the metal plate, the metal plate does not bend. Therefore, the substrate and the metal plate can be uniformly pressurized through the cushion material and the metal plate.

  Still further, in the method for manufacturing a multilayer wiring board according to the present invention, the cushion material is a fine cloth made of stainless fiber. Thereby, even if it heat-press-molds at high temperature, there is little damage and deterioration of a cushion material, and it can be reused many times and is suitable.

  Furthermore, in the method for manufacturing a multilayer wiring board according to the present invention, in the first step, the portion of the first metal plate that does not contact the cushion material and the portion of the second metal plate that does not contact the cushion material. The intermediate plate is arranged so as to be aligned at a predetermined position by contacting the end face of the intermediate plate arranged so as to contact the metal plate holding the substrate with the rod body connecting It is characterized by that. Thereby, the alignment of the intermediate plate is facilitated, the workability is improved, and the multilayer wiring board can be easily formed.

  Moreover, in the manufacturing method of the multilayer wiring board of the present invention, in the first step, of the two opposing surfaces of the first metal plate and the second metal plate, a surface that contacts the cushion material; A second cushion material is disposed on each of the opposing surfaces. Thereby, the influence of minute unevenness on the surface of the metal plate facing the metal plate can be reduced. Therefore, the metal plate and the substrate can be pressed more uniformly.

  Furthermore, in the method for manufacturing a multilayer wiring board according to the present invention, the first metal plate and the second metal plate are in contact with the substrate and the metal plate, respectively, on the surfaces that are in contact with the second cushion material. It has the convex part which has the main surface of the shape substantially the same as the shape of a surface. Accordingly, the surface in contact with the metal plate via the second cushion material becomes substantially the same as the shape of the contact surface between the metal plate and the substrate, and the pressure applied to the metal plate can be uniformly transmitted to the metal plate and the substrate. .

  Furthermore, in the method for manufacturing a multilayer wiring board according to the present invention, the second cushion material is a polyimide plate sandwiched between a polyimide plate or a copper plate, or a cloth made of stainless fiber. Thereby, a metal plate and a board | substrate can be pressurized uniformly suitably.

  In the method for manufacturing a multilayer wiring board according to the present invention, the shape of the contact surface between the substrate and the metal plate and the shape of the contact surface between the metal plate and the cushion material are substantially the same. That is, since the pressure is applied only to the portion where the metal plate and the substrate are present in the pressing direction of the metal plate, there is no bending of the metal plate. Therefore, the substrate and the metal plate can be uniformly pressurized through the cushion material and the metal plate. Therefore, it is possible to prevent poor connection and voids.

  Hereinafter, a manufacturing method of a multilayer wiring board to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view showing a step of heat-press molding a substrate sandwiched between metal plates in the method for manufacturing a multilayer wiring board of the present invention. In the method for manufacturing a multilayer wiring board of the present invention, first, the substrate 10 is held between a pair of metal plates 20.

  The metal plate 20 is, for example, a rectangular plate material having a predetermined size. It becomes wiring of the multilayer wiring board in which this metal plate 20 was formed. Examples of the metal plate 20 include, but are not limited to, a metal foil formed of a conductor such as copper. The shape of the metal plate 20 may be the same as the shape of the substrate 10. The metal plate 20 is aligned with a predetermined position with respect to the substrate 10, and the substrate 10 is held between the pair of metal plates 20. For example, when the shape of the metal plate 20 is the same shape as the substrate 10, the substrate 10 is aligned so that the metal plate 20 does not protrude from the substrate 10 when the main surface of the substrate 10 is viewed from above. 10 is held by a metal plate 20.

  The substrate 10 is a rectangular plate material having a predetermined size formed of, for example, a polyimide resin material or the like, and has bumps formed of a conductor such as copper. The bumps formed on the substrate 10 are formed by etching a conductor such as copper provided on one metal plate 20. At this time, etching of the metal plate 20 can be prevented by providing an etching barrier layer made of nickel or the like between the conductor and the metal plate 20. The substrate 10 having bumps is formed by applying a polyimide resin material or the like as an insulator on the metal plate 20 on which the bumps are formed.

  Next, the intermediate plate 50 is arranged while aligning the substrate 10 held by the metal plate 20 so as to be arranged at a predetermined position of the metal plate 20 on the surface that does not come into contact with the substrate 10. The plate 20 and the substrate 10 and the intermediate plate 50 are alternately stacked. At this time, the intermediate plate 50 is positioned so that the shape of the contact surface between the metal plate 20 and the substrate 10 does not protrude from the intermediate plate 50 when viewed from above the metal plate and the substrate 10 in the stacking direction. Match. The shape of the intermediate plate 50 is a metal plate-like member such as stainless steel having a main surface having a shape larger than the shape of the contact surface between the metal plate 20 and the substrate 10 and a predetermined thickness. The intermediate plate 50 is disposed between the intermediate plate 50 and the substrate 10 sandwiched between the metal plates 20, and can transmit pressure to the metal plate 20 and the substrate 10 at the time of heat and pressure molding.

  The second cushion material 42 is arranged while being aligned at a predetermined position on the surface of the plurality of intermediate plates 50 that are not in contact with the metal plate 20 of the outermost intermediate plate 50. The The second cushion material 42 may be the same shape as the shape of the contact surface between the metal plate 20 and the substrate 10 or a shape larger than the shape of the contact surface between the metal plate 20 and the substrate 10. When the second cushion material 42 is seen through from above in the stacking direction of the metal plate 20 and the substrate 10, the shape of the contact surface between the metal plate 20 and the substrate 10 is the outer shape of the second cushion material 42. Align so that it does not protrude from the shape. As a result, even if there are minute irregularities on the surfaces of the first metal plate 31 and the second metal plate 32 described below facing the metal plate 20, the influence of the irregularities being transmitted to the metal plate 20 and the substrate 10 is affected. Can be reduced. Therefore, the metal plate 20 and the substrate 10 can be more uniformly pressed.

  Examples of the second cushion material 42 include a polyimide plate or a polyimide plate sandwiched between copper plates or a cloth made of stainless steel. Thereby, a metal plate and a board | substrate can be pressurized uniformly suitably.

  The metal plate 20 and the substrate 10 are sandwiched between the first metal plate 31 and the second metal plate 32 via the second cushion material 42 and the intermediate plate 50. And the 1st cushion material 41 is distribute | arranged to the surface which opposes the surface which pinches | interposes the board | substrate 10 and the metal plate 20 among the two surfaces which each oppose to this 1st metal plate 31 and the 2nd metal plate 32, respectively.

  The first cushion material 41 absorbs irregularities on the surface of the pressurizing portion of a heating and pressing molding means such as a press machine, and can uniformly pressurize the first metal plate 31 and the second metal plate 32. it can. The first cushion material 41 is a predetermined surface of a surface facing a surface sandwiching the metal plate 20 and the substrate 10 out of two surfaces facing each other of a first metal plate 31 and a second metal plate 32 described below. It is arranged while positioning. When the first cushion material 41 is seen through from above in the stacking direction of the metal plate 20 and the substrate 10, the shape of the contact surface of the metal plate 20 and the substrate 10 is the outer shape of the first cushion material 41. Align so that it does not protrude from the shape. Examples of the first cushion material 41 include a fine cloth made of stainless steel fibers. Thereby, even if it heat-press-molds at high temperature, there are few damages and deterioration of the 1st cushion material 41, and it can reuse again and again, and is suitable.

  The first cushion material 41 may be the same shape as the shape of the contact surface between the metal plate 20 and the substrate 10 or a shape larger than the shape of the contact surface between the metal plate 20 and the substrate 10. When the first cushion material 41 is relatively small, the end portion of the cushion material may be unwound or deformed by being used a plurality of times. As a result, the cushion material may not be able to cover the entire contact surface between the metal plate and the substrate, causing non-uniform pressurization. However, since the first cushion material 41 is larger than the shape of the contact surface between the metal plate 20 and the substrate 10, the first cushion material 41 is unraveled and deformed to the portion that contacts the first metal plate 31 or the second metal plate 32. The influence is reduced and the first cushion material 41 can be reused.

  The first metal plate 31 and the second metal plate 32 are both substantially the same shape, have a predetermined thickness, and are made of a material such as stainless steel. The first metal plate 31 and the second metal plate 32 have a metal plate 20 sandwiched between the first metal plate 31 and the second metal plate 32 so that the surface of the first metal plate 31 and the second metal plate 32 in contact with the first cushion material 41 is in contact with each other. And the shape of the contact surface between the substrate 10 and the substrate 10. The first metal plate 31 and the second metal plate 32 are disposed while being aligned with each other at a predetermined position on the surface of the second cushion material 42 that does not contact the intermediate plate 50. When the first metal plate 31 is seen through from above the stacking direction of the metal plate 20 and the substrate 10, the shape of the contact surface of the metal plate 20 and the substrate 10, the first metal plate 31 and the first metal plate 31 Alignment is performed so that the shape of the contact surface of the first cushion material 41 matches without protruding. Similarly to the first metal plate 31, the second metal plate 32 is aligned.

  The first metal plate 31 and the second metal plate 32 may be convex plate members having a convex cross section as shown in FIG. In this case, on the contact surface between the first metal plate 31 or the second metal plate 32 and the first cushion material 41, a convex portion having a main surface that is substantially the same as the shape of the metal plate 20, the substrate 10, and the contact surface. By being formed, the first metal plate 31 and the second metal plate 32 having a convex cross section are obtained. By adopting such a shape, no pressure is applied to a portion where the first cushion material 41 and the first metal plate 31 or the second metal plate 32 are not in contact with each other, so the first metal plate 31 and the second metal plate 31 The metal plate 32 does not bend. Therefore, the substrate 10 and the metal plate 20 can be uniformly pressed through the first cushion material 41, the first metal plate 31, and the second metal plate 32. In addition, although this convex part may be provided with the convex part on the flat plate-shaped plate, it is more preferable that it is integrally formed. Further, a convex portion having a main surface substantially the same as the shape of the contact surface of the substrate 10 and the metal plate 20 may be provided on the surface that contacts the second cushion material 42. That is, the metal plate which has this convex part on both surfaces may be sufficient. In this case, it is preferable that the respective convex portions are provided at corresponding positions on both surfaces of the metal plate. Thereby, when arrange | positioning the convex part of both surfaces above or below the board | substrate 10 and the metal 20, it becomes possible to arrange | position so that it may not protrude from the board | substrate 10 and the metal plate 20 together. Therefore, the surface in contact with the metal plate 20 through the second cushion material 42 is substantially the same as the shape of the contact surface of the metal plate 20 and the substrate 10, and the pressure applied to the first metal plate 31 and the second metal plate 32. Can be uniformly transmitted to the metal plate 20 and the substrate 10.

  In this manner, the metal plate 20 and the substrate 10 can be heated and pressed through the first metal plate 31, the second metal plate 32, and the first cushion material 41 to manufacture a multilayer wiring board. In the multilayer wiring board manufactured in this way, pressure is uniformly applied to the metal plate 20 and the substrate 10, and connection failure between the metal plate 20 and the substrate 10 and generation of voids can be prevented.

  In addition, the board | substrate 10, the metal plate 20, etc. are laminated | stacked based on the shape of the contact surface of the 1st metal plate 31 or the 2nd metal plate 32, and the 1st cushion material 41. FIG. At this time, for example, the second metal plate 32 is arranged on the first cushion material 41, and light that indicates the shape of the contact surface is irradiated from above, and the substrate 10 and the metal plate 20 are matched to this light. May be aligned. Further, although the intermediate plate 50 and the second cushion material 42 depend on the shape and size, the intermediate plate 50 is irradiated with another light from above as in the case of the substrate 10 and the metal plate 20 and is matched to the light. Alternatively, the second cushion material 42 may be aligned.

  The method of aligning the position of the intermediate plate 50 is not limited to the above method. For example, as shown in FIG. 2, the first metal plate is provided at a location where the first cushion material 41 of the first metal plate 31 does not contact and a location where the first cushion material 41 of the second metal plate 32 does not contact. The rod body 60 is inserted so that 31 and the 2nd metal plate 32 may be connected. That is, the non-convex portions of the first metal plate 31 and the second metal plate 32 are connected by the rod body 60. Then, by bringing the end surface of the intermediate plate 50 into contact with the rod body 60, the intermediate plate 50 can be disposed at a predetermined position on the surface of the metal plate 20 that does not contact the substrate 10. Thereby, the position alignment of the intermediate | middle board 50 can be performed easily and workability | operativity improves. Similarly, the metal plate 20 and the substrate 10 may be aligned.

  Furthermore, the manufacturing method of the multilayer wiring board of the present invention can manufacture a multilayer wiring board at the same time in two rows by using a pair of metal plates having two convex portions, and the production efficiency is doubled. Become.

  Further, the first metal plate and the second metal plate sandwiching the metal plate 20 and the substrate 10 have a contact surface shape between the metal plate 20 and the substrate 10 as shown in FIG. It may be a flat plate material having substantially the same shape as the shape of the contact surface. As a result, there is no portion where the metal plate 20 and the substrate 10 do not exist in the pressurizing direction of the first metal plate 34 and the second metal plate 35, so that the first metal plate 31 and the second metal plate 32 are bent. No. Therefore, the substrate 10 and the metal plate 20 can be uniformly pressed through the first cushion material 41, the first metal plate 31, and the second metal plate 32.

  Examples of the method for manufacturing a multilayer wiring board according to the present invention will be described below. The present invention is not limited to this embodiment, and can be modified without departing from the gist of the present invention.

[Example 1]
First, a multilayer wiring board was manufactured by a conventional method. A 255 mm × 335 mm polyimide substrate sandwiched between 255 mm × 335 mm copper metal plates of the same type as this substrate was used. Then, a stainless steel plate-like intermediate plate having a larger main surface than the substrate and the metal plate is prepared, and the substrate, the metal plate, and the intermediate plate are alternately laminated so that the intermediate plate is on the outer side. The substrate and the metal plate were sandwiched between intermediate plates while being aligned to a predetermined position.

  A second cushion material having a size of 255 mm × 335 mm in which a copper plate is disposed on both surfaces of a plate-like polyimide resin was disposed at a predetermined position on the surface not in contact with the metal plate of the intermediate plate while being aligned. Furthermore, a stainless steel flat metal plate having a major surface larger than the intermediate plate was sandwiched while being positioned at a predetermined position on the surface not in contact with the intermediate plate of the second cushion material. A 370 mm × 560 mm Naslon (registered trademark) was placed as a first cushion material at a predetermined position on the surface of the metal plate opposite to the surface sandwiching the metal plate. Thus, the board | substrate and metal plate pinched | interposed with the metal plate were distribute | arranged to the press, and the board | substrate and the metal plate were heat-press-molded with the pressure of 5.1518 MPa, and the temperature of 25 degreeC and 335 degreeC.

  Among the substrates and metal plates laminated in this manner, the pressure applied to the surface of the uppermost substrate and metal plate during heating and pressing was measured. Among these, the result in the measurement at 335 ° C. is shown in FIG. As shown in FIG. 4, in the case of Example 1, it was found that the pressure applied to the end portion and the center portion was different. It was found that the pressure applied to the end portion and the center portion was different in the heat and pressure molding at 25 ° C.

[Example 2]
Next, examples of the method for manufacturing a multilayer wiring board according to the present invention will be described. In Example 2, the substrate, the metal plate, and the intermediate plate used in Example 1 were used and laminated in the same manner as in Example 1. A second cushion material having a size of 255 mm × 335 mm, which is different only in size compared to Example 1, was placed at a predetermined position on the surface of the intermediate plate that is not in contact with the metal plate while being aligned. Further, a metal plate having a convex portion of 255 mm × 335 mm on one main surface of a flat plate of 400 mm × 590 mm made of stainless steel at a predetermined position on the surface not in contact with the intermediate plate of the second cushion material, It was pinched while aligning so that the convex part went to. Then, Naslon (registered trademark) of 370 mm × 560 mm, which is the same as that of the first embodiment, is arranged while being aligned as a first cushion material at a predetermined position on the surface of the metal plate facing the surface sandwiching the metal plate. . The thus laminated substrate and metal plate were placed in a press machine and heated and pressed in the same manner as in Example 1. And the pressure concerning a board | substrate and a metal plate was shown in FIG. As a result, it was found that the pressure was uniformly applied as compared with Example 1. Further, it was found that the pressure was uniformly applied even in the heat and pressure molding at 25 ° C.

[Example 3]
In Example 3, the substrate, the metal plate, the intermediate plate, the metal plate, and the first cushion material used in Example 2 were used. Moreover, the 2nd cushion material of 370 mm x 560 mm from which only a magnitude | size compared with Example 1 was used. This was laminated in the same manner as in Example 2. The laminated substrate and metal plate were placed in a press machine and subjected to heat and pressure molding in the same manner as in Example 1. And the pressure concerning a board | substrate and a metal plate was shown in FIG. As a result, it was found that the pressure was uniformly applied as compared with Example 1. Further, it was found that the pressure was uniformly applied even in the heat and pressure molding at 25 ° C.

[Example 4]
In Example 4, the substrate, the metal plate, the intermediate plate, the first cushion material, and the second cushion material used in Example 3 were used. Moreover, it laminated | stacked similarly to Example 3 using the metal plate of 400 mm x 590 mm which has a convex part of 255 mm x 335 mm on both surfaces. The laminated substrate and metal plate were placed in a press machine and subjected to heat and pressure molding in the same manner as in Example 1. And the pressure concerning a board | substrate and a metal plate was shown in FIG. As a result, it was found that the pressure was uniformly applied as compared with Example 1. Further, it was found that the pressure was uniformly applied even in the heat and pressure molding at 25 ° C.

[Example 5]
In Example 5, the substrate, the metal plate, the intermediate plate, the first cushion material, and the second cushion material used in Example 2 were used. And the flat metal plate of the magnitude | size of 255 mm x 335 mm which is the same magnitude | size as a board | substrate and a metal plate was used. This was laminated in the same manner as in Example 2. At this time, the metal plate was aligned so that the shapes of the contact surfaces of the metal plate 31 and the first cushion material coincided with the shapes of the contact surfaces of the metal plate and the substrate without protruding. The laminated substrate and metal plate were placed in a press machine and subjected to heat and pressure molding in the same manner as in Example 1. And the pressure concerning a board | substrate and a metal plate was shown in FIG. As a result, it was found that the pressure was uniformly applied as compared with Example 1. Further, it was found that the pressure was uniformly applied even in the heat and pressure molding at 25 ° C.

[Example 6]
In Example 6, the substrate, the metal plate, the intermediate plate, the metal plate, and the first cushion material used in Example 5 were used. And what was used in Example 3 was used for the 2nd cushion material. This was laminated in the same manner as in Example 5. The laminated substrate and metal plate were placed in a press machine and subjected to heat and pressure molding in the same manner as in Example 1. And the pressure concerning a board | substrate and a metal plate was shown in FIG. As a result, it was found that the pressure was uniformly applied as compared with Example 1. Further, it was found that the pressure was uniformly applied even in the heat and pressure molding at 25 ° C.

  As described above, the maximum value and the minimum value of the pressure on the substrate surface, the maximum value of the equivalent stress, and the maximum value and the minimum value of the tension on the substrate surface when the multilayer wiring board manufactured in Example 1 to Example 6 is molded. The results are summarized in Table 1.

  From this result, it was shown that the pressure difference applied to the substrate and the metal plate was smaller in Examples 2 to 6 than in Example 1. Thereby, a board | substrate and a metal plate can be pressurized uniformly.

It is sectional drawing explaining an example of the manufacturing method of the multilayer wiring board of this invention. It is sectional drawing at the time of aligning using the rod in the manufacturing method of the multilayer wiring board of this invention. It is sectional drawing explaining another example of the manufacturing method of the multilayer wiring board of this invention. It is a figure which shows a state in the pressure concerning the board | substrate and metal plate of Example 1. FIG. It is a figure which shows the state concerning the pressure concerning the board | substrate and metal plate of Example 2. FIG. It is a figure which shows the state concerning the pressure concerning the board | substrate and metal plate of Example 3. FIG. It is a figure which shows a state in the pressure concerning the board | substrate and metal plate of Example 4. FIG. It is a figure which shows the state concerning the pressure concerning the board | substrate and metal plate of Example 5. FIG. It is a figure which shows the state concerning the pressure concerning the board | substrate and metal plate of Example 6. FIG.

Explanation of symbols

10 substrate 20 metal plate 31 first metal plate 32 second metal plate 41 first cushion material 42 second cushion material 50 intermediate plate

Claims (8)

A method of manufacturing a multilayer wiring board in which a substrate is sandwiched between metal plates,
A first step of sandwiching the substrate sandwiched between the metal plates between a first metal plate and a second metal plate;
A second step of disposing a cushioning material on each of the opposing surfaces of the first metal plate and the second metal plate, the surfaces facing the surface sandwiching the substrate and the metal plate;
A third step of heating and press-molding the metal plate and the substrate through the first metal plate, the second metal plate, and the cushion material;
Each of the contact surfaces of the first metal plate, the second metal plate, and the cushion material has substantially the same shape as the contact surface of the substrate and the metal plate. A method for manufacturing a wiring board.   Each of the first metal plate and the second metal plate has a convex portion having a main surface having a shape substantially the same as a shape of a contact surface between the substrate and the metal plate on a surface that contacts the cushion material. The method for producing a multilayer wiring board according to claim 1, wherein:   2. The surface of the first metal plate and the second metal plate in contact with the cushion material is substantially the same as the shape of the contact surface between the substrate and the metal plate. Manufacturing method of multilayer wiring board.   The method for manufacturing a multilayer wiring board according to claim 1, wherein the cushion material is a cloth made of stainless steel fibers. In the first step,
The rod that connects the portion of the first metal plate that does not contact the cushion material and the portion of the second metal plate that does not contact the cushion material contacts the metal plate that sandwiches the substrate. 3. The method of manufacturing a multilayer wiring board according to claim 2, wherein the intermediate plate is arranged so as to be aligned at a predetermined position by contacting end faces of the intermediate plate arranged in this manner. In the first step,
Of the two opposing surfaces of the first metal plate and the second metal plate, a second cushion material is arranged on each of the surfaces facing the surface in contact with the cushion material. The manufacturing method of the multilayer wiring board of Claim 1.   The first metal plate and the second metal plate are convex surfaces having substantially the same shape as the shape of the contact surface between the substrate and the metal plate on the surface that contacts the second cushion material, respectively. The method for manufacturing a multilayer wiring board according to claim 6, further comprising a portion.   7. The method for manufacturing a multilayer wiring board according to claim 6, wherein the second cushion material is a polyimide plate sandwiched between a polyimide plate or a copper plate, or a cloth made of stainless steel fibers.