JP2011159666A - Method of manufacturing wiring board with reinforcing member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a wiring board with a reinforcing member, capable of surely buffering a stress applied to the reinforcing member and preventing the wiring board from warpage. <P>SOLUTION: The wiring board 11 with a stiffener includes a wiring board 40, having a principal board plane 41 and a rear board face 42, and the stiffener 31 including a plurality of split pieces 36 and jointed with a side of the principal board plane 41. An upper tool 92 including a plurality of storage parts 95 is placed on the side of the principal board plane 41 during a tool arrangement step. The plurality of split pieces 36 are stored in respective storage parts 95 during a jointing step, thereby laying out the respective split pieces 36 in a frame as a whole, while mutually positioning them and jointing them on the principal board plane 41. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a wiring board with a reinforcing material provided with a reinforcing material for preventing warping of the wiring board.

  In recent years, semiconductor integrated circuit elements (IC chips) used as computer microprocessors and the like have become increasingly faster and more functional, with an accompanying increase in the number of terminals and a tendency to narrow the pitch between terminals. . In general, a large number of terminals are densely arranged on the bottom surface of an IC chip, and such a terminal group is connected to a terminal group on the motherboard side in the form of a flip chip. However, it is difficult to connect the IC chip directly on the mother board because there is a large difference in the pitch between the terminals on the IC chip side terminal group and the mother board side terminal group. For this reason, a method is generally adopted in which a semiconductor package is prepared by mounting an IC chip on an IC chip mounting wiring board, and the semiconductor package is mounted on a motherboard (see, for example, Patent Document 1).

  The IC chip is generally formed using a semiconductor material (for example, silicon) having a thermal expansion coefficient of about 2.0 ppm / ° C. to 5.0 ppm / ° C. On the other hand, the IC chip mounting wiring board is often a resin wiring board formed using a resin material having a considerably larger thermal expansion coefficient. As an example of this resin wiring board, a structure in which a buildup layer is formed on the front surface and the back surface of a core substrate has been put into practical use. In this resin wiring substrate, for example, a resin substrate (glass epoxy substrate or the like) in which a reinforcing fiber is impregnated with a resin is used as a core substrate. Then, by utilizing the rigidity of the core substrate, a resin layer and a conductor layer are alternately laminated on the front surface and the back surface of the core substrate, thereby forming a buildup layer. That is, in this resin wiring substrate, the core substrate plays a role of reinforcement and is formed much thicker than the build-up layer. In addition, wiring (specifically, a through-hole conductor or the like) is formed through the core substrate for conduction between buildup layers formed on the front surface and the back surface.

  By the way, in recent years, with the increase in the speed of semiconductor integrated circuit elements, the signal frequency used has become a high frequency band. In this case, the wiring penetrating the core substrate contributes as a large inductance, leading to transmission loss of high-frequency signals and circuit malfunction, which hinders speeding up. In order to solve this problem, it has been proposed that the resin wiring substrate is a substrate that does not have a core substrate (see, for example, Patent Document 2). Since this substrate is obtained by shortening the overall wiring length by omitting a relatively thick core substrate, the transmission loss of high-frequency signals is reduced, and the semiconductor integrated circuit element can be operated at high speed. .

  However, if the core substrate is omitted, the resin wiring board is thinned, and thus the rigidity of the resin wiring board is inevitably lowered. In this case, when the solder used for flip chip connection is cooled, the resin wiring board tends to warp to the chip mounting surface side due to the influence of thermal stress caused by the difference in thermal expansion coefficient between the chip material and the substrate material. Become. As a result, cracks occur in the chip bonding portion, and open defects are likely to occur. That is, when a semiconductor package is configured using the above IC chip, there arises a problem that high yield and reliability cannot be realized.

  In order to solve the above problem, there has been proposed a semiconductor package 100 in which a frame-like stiffener 105 (reinforcing material) is attached to one side of the resin wiring substrate 101 (the mounting surface 102 of the IC chip 106) (see FIG. 22). ). The stiffener 105 is formed using a material (for example, a metal material) having higher rigidity than the resin wiring substrate 101. Here, when the semiconductor package 100 is manufactured using the metal stiffener 105, the thermal expansion coefficient of the resin wiring substrate 101 is larger than the thermal expansion coefficient of the metal stiffener 105, and therefore, it is caused by the difference in thermal expansion coefficient. The resin wiring board 101 may be warped under the influence of the thermal stress.

  As a countermeasure, a technique has been proposed in which slits are formed in a part of the stiffener so as to distribute thermal stress (see, for example, Patent Document 3). FIG. 23 shows the stiffener 110 used in the semiconductor package of Patent Document 3. The stiffener 110 in FIG. 23 is formed in a rectangular frame shape having four corners 111, and an opening 112 for accommodating an IC chip is formed at the center of the stiffener 110. In addition, the stiffener 110 is provided with slits 114 extending from the corners of the opening 112 to the corresponding corners 111 of the stiffener 110.

JP 2002-26500 A (FIG. 1 and the like) Japanese Unexamined Patent Publication No. 2002-26171 (FIG. 5 etc.) JP 2007-299887 A (FIG. 3 etc.)

  By the way, in the conventional stiffener 110, the slit 114 is formed such that one end thereof is opened in the opening 112 and the other end is located in the vicinity of the corner 111. That is, the stiffener 110 is not completely divided by the slit 114 and is partially connected. For this reason, thermal stress may concentrate on the connected portion of the stiffener 110, and in this case, it becomes impossible to eliminate the warp of the resin wiring board. If the resin wiring board is warped, it is difficult to mount the IC chip, and the product reliability is lowered.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a method of manufacturing a wiring board with a reinforcing material that can reliably relieve stress applied to the reinforcing material and prevent warping of the wiring board. There is to do.

  As means for solving the above problems (means 1), the substrate has a main surface and a back surface, and has a structure in which a plurality of resin insulation layers and a plurality of conductor layers are laminated, and chip components are connected. A plurality of possible main surface side connection terminals are joined to the plate main surface side disposed on the substrate main surface, the main surface side connection terminals are exposed, and the plurality of main surface side connection terminals are exposed. A method of manufacturing a wiring board with a reinforcing material, comprising a reinforcing material consisting of a plurality of divided pieces that form a frame shape as a whole, wherein the plurality of divided pieces can be arranged in a frame shape as a whole while positioning each other. A jig placement step of placing a jig having a plurality of housing portions on the substrate main surface side, and housing the plurality of divided pieces in the plurality of housing portions, respectively, And a joining step for joining the split pieces. There are provided methods for producing the wood with the wiring board.

  Therefore, according to the invention described in the means 1, in the jig arranging step, the jig is arranged on the substrate main surface side. In the subsequent joining step, the plurality of divided pieces are respectively stored in the plurality of storage portions in the jig, so that each divided piece is positioned as a whole while being positioned with respect to each other, and the plurality of divided pieces are the substrate main surface. To be joined. If it does in this way, a plurality of division pieces can be quickly joined to an exact position in the substrate main surface side, and the strength of a wiring board can be certainly raised by the reinforcing material which consists of each division piece. In addition, since the reinforcing material is completely divided by each divided piece, the thermal stress applied to the reinforcing material due to the difference in thermal expansion coefficient between the reinforcing material and the wiring board can be surely alleviated, and the wiring with the reinforcing material Warpage of the substrate can be prevented.

  The reinforcing material is preferably more rigid than the resin material constituting the wiring board. The reason is that if the reinforcing material itself is given high rigidity, it can be given high rigidity to the wiring board by surface bonding, and becomes stronger against externally applied stress. In addition, if the reinforcing material has high rigidity, the wiring board can be provided with sufficiently high rigidity even if the reinforcing material is thinned, so that the thinning of the entire wiring board with reinforcing material is not hindered.

  The reinforcing material is preferably formed using, for example, a highly rigid metal material or ceramic material. For example, the reinforcing material may be formed of a composite material in which an inorganic material is contained in a resin material.

  Examples of the metal material constituting the reinforcing material include iron, gold, silver, copper, copper alloy, iron nickel alloy, silicon, and gallium arsenide. Examples of the ceramic material constituting the reinforcing material include low-temperature fired materials such as alumina, glass ceramic, and crystallized glass, aluminum nitride, silicon carbide, and silicon nitride. As the resin material constituting the reinforcing material, epoxy resin, polybutene resin, polyamide resin, polybutylene terephthalate resin, polyphenylene sulfide resin, polyimide resin, bismaleimide / triazine resin, polycarbonate resin, polyphenylene ether resin, acrylonitrile butadiene styrene copolymer There is a coalescence (ABS resin).

  The reinforcing material is bonded to the main surface of the wiring board, but the bonding method is not particularly limited, and a well-known method suitable for the nature, shape, etc. of the material forming the reinforcing material is adopted. be able to. For example, the joining surface of the reinforcing material is preferably joined to the substrate main surface via an adhesive. In this way, the reinforcing material can be reliably and easily joined to the wiring board. Examples of the adhesive include an acrylic adhesive, an epoxy adhesive, a cyanoacrylate adhesive, and a rubber adhesive.

  At least one divided piece of the plurality of divided pieces constituting the reinforcing material may be formed of a material different from other divided pieces, or have a thickness different from that of the other divided pieces. But you can.

  In the wiring board, the part where the chip component is mounted and the part where the conductor layer is formed may have different strength and thermal expansion coefficient than the peripheral part. In this case, the warping of the wiring board with the reinforcing material is surely prevented by joining the split pieces formed of different materials and the split pieces having different thicknesses according to the difference in strength and thermal expansion coefficient in the wiring board. be able to. Moreover, even if the formation material and thickness of each division | segmentation piece differ, each division | segmentation piece can be rapidly joined to an exact position by using the said jig | tool.

  At least one divided piece of the plurality of divided pieces may be bonded using an adhesive different from the other divided pieces. When the forming materials of the plurality of divided pieces are different, the warping of the wiring board with the reinforcing material can be surely prevented by bonding the divided pieces using an adhesive suitable for the forming materials.

  At least one of the plurality of divided pieces may be formed to include a conductive metal material, and may be bonded to the conductor layer of the wiring board using a conductive adhesive. In this case, it becomes possible to electrically connect to the conductor layer of the wiring board through the divided piece formed including the conductive metal material, and the divided piece can be used as the external terminal.

  The reinforcing material has an outer dimension set to be larger than an outer dimension of the wiring board, and the outer edge portion of the reinforcing material protrudes from the outer edge portion of the wiring board in the substrate plane direction as a whole. It may be joined to. If it does in this way, it will be in the state where the outer edge part of the wiring board was relatively retracted rather than the outer edge part of a reinforcing material, and it will become difficult for other members etc. to contact the outer edge part of a wiring board. As a result, the outer edge portion of the wiring board can be reliably protected with the reinforcing material, and damage to the outer edge portion of the wiring board can be prevented.

  The shape of the slit formed between the divided pieces in the reinforcing material is not particularly limited, and may be a linear shape or a non-linear shape. A specific example of the non-linear shape is a crank shape, for example. In the case of forming this non-linear slit in the reinforcing material, even if the position of each divided piece is shifted in order to relieve the thermal stress applied to the reinforcing material, each of the divided pieces in the surface direction of the reinforcing material. Some will overlap. And the curvature of a wiring board can be prevented reliably by the overlapping part of each division | segmentation piece.

  It is preferable that a plane-like conductor layer is disposed over a plurality of layers at a position corresponding to the position where the slit is formed on the wiring board. In this case, the portion where the slit is formed in the reinforcing material has low rigidity, but by providing a plane conductor layer on a plurality of layers of the wiring board, the portion where the rigidity is low can be reinforced. For this reason, the rigidity of the wiring board with a reinforcing material can be sufficiently ensured.

  The plate-like wiring board has a substrate main surface and a substrate back surface, has a structure in which a plurality of resin insulation layers and a plurality of conductor layers are laminated, and a plurality of main surface sides to which chip components can be connected A structure in which connection terminals are arranged on the main surface of the substrate is used. Examples of the wiring board include a coreless wiring board that does not have a core, and is manufactured through the following steps.

  First, in the base resin sheet forming step, the base resin sheet is formed on a support substrate used for reinforcement during manufacturing, and in the metal sheet body arranging step, the two metal foils are adhered in a peelable state. A laminated metal sheet is placed on the base resin sheet. Thereafter, in the metal sheet body sealing step, a resin insulating sheet to be the resin insulating layer is disposed so as to wrap the laminated metal sheet body, and the laminated metal is interposed between the resin insulating sheet and the base resin sheet. The sheet body is sealed. And in a laminated body formation process, the wiring pattern which should become the said conductor layer, and the resin insulating sheet which should become the said resin insulating layer are laminated | stacked alternately on the said resin insulating sheet which sealed the said laminated metal sheet body. By this step, a laminated body including the wiring laminated portion to be the wiring board on the laminated metal sheet body is formed. Further, in the peripheral portion cutting step, the laminate is cut along with the support substrate along the boundary between the wiring laminated portion and the peripheral portion, and the peripheral portion is removed. The support substrate is peeled off at the interface of the metal sheet (two metal foils). In the connection terminal forming step, the metal foil on the surface of the wiring laminated portion is patterned to form a plurality of main surface side connection terminals on the substrate main surface.

  In the wiring board, it is preferable that the plurality of via conductors are formed in the plurality of resin insulation layers, and the plurality of via conductors are expanded in the same direction in each layer of the plurality of resin insulation layers. In this way, a coreless wiring board that does not include a core board can be reliably manufactured.

1 is a schematic cross-sectional view showing a semiconductor package of an embodiment. The top view which shows a semiconductor package. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. Explanatory drawing which shows the manufacturing method of a wiring board with a stiffener. The top view which shows the jig | tool for arrangement | positioning of each division | segmentation piece. Sectional drawing which shows the jig | tool for arrangement | positioning of each division | segmentation piece. Sectional drawing which shows the wiring board with a stiffener of another embodiment. Sectional drawing which shows the wiring board with a stiffener of another embodiment. The principal part sectional drawing which shows the wiring board with a stiffener of another embodiment. The top view which shows the wiring board with a stiffener of another embodiment. The top view which shows the jig | tool for arrangement | positioning of each division | segmentation piece. The top view which shows the wiring board with a stiffener of another embodiment. The top view which shows the wiring board with a stiffener of another embodiment. The principal part sectional drawing which shows the wiring board with a stiffener of another embodiment. The perspective view which shows the semiconductor package of a prior art. The top view which shows the stiffener of a prior art.

  Hereinafter, an embodiment in which the present invention is embodied in a wiring board with a reinforcing material will be described in detail with reference to the drawings.

  As shown in FIGS. 1 and 2, the semiconductor package 10 of the present embodiment includes a BGA (ball grid array) composed of a wiring board 11 with stiffeners (wiring board with reinforcing material) and an IC chip 21 (chip parts). ). Note that the form of the semiconductor package 10 is not limited to BGA alone, and may be PGA (pin grid array), LGA (land grid array), or the like. The IC chip 21 is a rectangular flat plate having a length of 15.0 mm, a width of 15.0 mm, and a thickness of 0.8 mm, and is made of silicon having a thermal expansion coefficient of 4.2 ppm / ° C.

  The wiring board 11 with a stiffener includes a wiring board 40 and a wiring board stiffener (hereinafter referred to as “stiffener”) 31 that is a reinforcing material. The wiring substrate 40 of the present embodiment has a substrate main surface 41 and a substrate back surface 42 and is formed in a substantially rectangular shape in plan view of 50.0 mm long × 50.0 mm wide × 0.4 mm thick. The wiring board 40 is a coreless wiring board formed without including a core board, and is composed of four resin insulation layers 43, 44, 45, 46 made of epoxy resin and conductor layers 51 made of copper alternately. It has a laminated structure. In the wiring board 40 of the present embodiment, the thermal expansion coefficients of the resin insulating layers 43 to 46 are about 30 ppm / ° C., and the thermal expansion coefficient of the conductor layer 51 is about 17 ppm / ° C. In addition, a thermal expansion coefficient says the average value of the measured value between 0 degreeC-glass transition temperature (Tg).

  As shown in FIG. 1, terminal pads 52 (main surface side connection terminals) are arranged in an array on the substrate main surface 41 of the wiring substrate 40 (on the surface of the fourth resin insulating layer 46). Yes. Furthermore, a plurality of main surface side solder bumps 54 are disposed on the surface of the terminal pad 52. Each main surface side solder bump 54 is electrically connected to the surface connection terminal 22 of the IC chip 21. That is, the IC chip 21 is mounted on the substrate main surface 41 side of the wiring substrate 40. In addition, the area | region in which each terminal pad 52 and each main surface side solder bump 54 is formed is the IC chip mounting area 23 in which the IC chip 21 can be mounted.

  On the other hand, BGA pads 53 (back surface side connection terminals) are arranged in an array on the substrate back surface 42 of the wiring substrate 40 (on the lower surface of the first resin insulating layer 43). A plurality of backside solder bumps 55 for connecting a mother board are provided on the surface of each BGA pad 53, and the wiring board 40 is not shown in the figure by the backside solder bumps 55. Implemented above.

  Each resin insulation layer 43 to 46 is provided with a via hole 56 and a via conductor 57. Each via hole 56 has a truncated cone shape, and is formed by drilling the resin insulation layers 43 to 46 using a YAG laser or a carbon dioxide gas laser. Each via conductor 57 is a conductor whose diameter increases toward the back side 42 of the substrate (downward in FIG. 1), and electrically connects each conductor layer 51, the terminal pad 52 and the BGA pad 53 to each other. ing.

  As shown in FIGS. 1 and 2, the stiffener 31 is a rectangular frame-shaped reinforcing material having a length of 50.0 mm, a width of 50.0 mm, and a thickness of 2.0 mm, for example. Become. Each divided piece 36 is completely divided through a slit 39 extending from the frame inner surface 37 to the frame outer surface 38. Each of the divided pieces 36 of the present embodiment is a member having the same shape and the same size, and specifically, a trapezoidal member having a long side and a short side. Then, in the stiffener 31, by arranging each divided piece 36 with the short side facing the frame inner surface 37 side and the long side facing the frame outer surface 38 side, slits having a linear shape at each of the four corner portions. 39 is formed.

  The stiffener 31 (divided piece 36) is formed thicker than the wiring board 40 using a metal material (for example, copper). Therefore, the stiffener 31 (divided piece 36) is more rigid than the wiring board 40. Furthermore, the thermal expansion coefficient of the stiffener 31 is about 17 ppm / ° C., which is smaller than the thermal expansion coefficient (about 30 ppm / ° C.) of the resin insulating layers 43 to 46 constituting the wiring board 40.

  The stiffener 31 has a bonding surface 32 bonded to the wiring substrate 40 and a non-bonding surface 33 located on the opposite side of the bonding surface 32. The bonding surface 32 can come into surface contact with the outer peripheral portion of the substrate main surface 41 (that is, the region excluding the IC chip mounting region 23 in the substrate main surface 41).

  The stiffener 31 is formed with a rectangular opening 35 penetrating in a plan view opening at the center of the joint surface 32 and the center of the non-joint surface 33. The opening 35 exposes the terminal pad 52 and the main surface side solder bump 54. More specifically, the opening 35 is a hole having a substantially square cross section having a size of 20 mm long × 20 mm wide.

  As shown in FIG. 1, the joining surface 32 of each divided piece 36 constituting the stiffener 31 is surface-bonded to the outer peripheral portion of the substrate main surface 41 via an adhesive 30 (for example, an epoxy-based adhesive). Is done. If the stiffener-equipped wiring board 11 is configured in this way, the stiffener 31 imparts high rigidity to the wiring board 11.

  Next, the manufacturing method of the wiring board 11 with a stiffener is demonstrated.

  In the preparation step, the wiring board 40 is prepared and prepared in advance.

  The wiring board 40 is manufactured through the following wiring board manufacturing process. In the wiring board manufacturing process, first, as shown in FIG. 3, a support board 70 which is a board having sufficient strength such as a glass epoxy board and is used for reinforcement at the time of manufacture is prepared. Next, a base resin insulating layer 71 (base resin sheet) is formed on the support substrate 70 by attaching a sheet-like insulating resin base material made of an epoxy resin, so that the support substrate 70 and the base resin insulation layer 71 are separated. A base material 69 is obtained (underlying resin sheet forming step). Then, as shown in FIG. 4, the laminated metal sheet body 72 is arranged on one side of the base material 69 (specifically, the upper surface of the base resin insulating layer 71) (metal sheet body arranging step). Here, by disposing the laminated metal sheet body 72 on the base resin insulating layer 71, adhesiveness is secured to such an extent that the laminated metal sheet body 72 is not peeled off from the base resin insulating layer 71 in the subsequent manufacturing process. The laminated metal sheet body 72 is formed by closely attaching two copper foils 73 and 74 (metal foil) in a peelable state. Specifically, the laminated metal sheet body 72 is formed by laminating the copper foils 73 and 74 via metal plating (for example, chromium plating).

  Thereafter, as shown in FIG. 5, a sheet-like resin insulating base material 75 (resin insulating sheet) is disposed so as to wrap the laminated metal sheet body 72, and is vacuumed using a vacuum press-bonding hot press (not shown). By applying pressure and heating, the resin insulating substrate 75 is cured to form the fourth resin insulating layer 46. Here, the resin insulating layer 46 is in close contact with the laminated metal sheet body 72, and is in close contact with the base resin insulating layer 71 in the peripheral region of the laminated metal sheet body 72, thereby sealing the laminated metal sheet body 72 ( Metal sheet body sealing step).

  Then, as shown in FIG. 6, laser processing is performed to form via holes 56 at predetermined positions of the resin insulating layer 46, and then desmear processing is performed to remove smears in the via holes 56. Then, via conductors 57 are formed in each via hole 56 by performing electroless copper plating and electrolytic copper plating according to a conventionally known method. Further, the conductor layer 51 is patterned on the resin insulating layer 46 by performing etching by a conventionally known method (for example, semi-additive method) (see FIG. 7).

  The first to third resin insulation layers 43 to 45 and the conductor layer 51 are also formed by the same method as the above-described fourth resin insulation layer 46 and conductor layer 51, and the resin insulation layer 46 is formed on the resin insulation layer 46. (Laminate forming step). The laminated body 80 which laminated | stacked the laminated metal sheet body 72, the resin insulating layers 43-46, and the conductor layer 51 on the base material 69 is formed by the above process (refer FIG. 8). As shown in FIG. 8, a region located on the laminated metal sheet body 72 in the laminated body 80 is a wiring laminated portion 81 to be the wiring board 40.

  The laminated body 80 is cut by a dicing apparatus (not shown), and the peripheral region of the wiring laminated portion 81 in the laminated body 80 is removed (peripheral part cutting step). At this time, as shown in FIG. 8, at the boundary between the wiring laminated portion 81 and the peripheral portion 82 (the boundary indicated by the arrow in FIG. 8), the base material 69 (the support substrate 70 and the base layer) below the wiring laminated portion 81 is provided. The entire resin insulation layer 71) is cut. By this cutting, the outer edge portion of the laminated metal sheet body 72 sealed with the resin insulating layer 46 is exposed. That is, due to the removal of the peripheral portion 82, the close contact portion between the base resin insulating layer 71 and the resin insulating layer 46 is lost. As a result, the wiring laminated portion 81 and the base material 69 are connected via the laminated metal sheet body 72 only.

  Here, as shown in FIG. 9, the wiring laminated portion 81 is separated from the base material 69 by peeling at the interface between the two copper foils 73 and 74 in the laminated metal sheet 72 (peeling step). Then, as shown in FIG. 10, by patterning by etching the copper foil 73 on the lower surface of the wiring laminated portion 81 (resin insulating layer 46), terminal pads are formed on the outermost resin insulating layer 46. 52 is formed (connection terminal forming step).

  In the subsequent solder bump forming step, main surface side solder bumps 54 for IC chip connection are formed on the plurality of terminal pads 52 formed on the outermost resin insulation layer 46 (see FIG. 11). Specifically, a solder ball is placed on each terminal pad 52 using a solder ball mounting device (not shown), and then the solder ball is heated to a predetermined temperature and reflowed, whereby the main surface is placed on each terminal pad 52. Side solder bumps 54 are formed. Similarly, back-side solder bumps 55 are formed on the plurality of BGA pads 53 formed on the resin insulating layer 43.

  Next, a stiffener 31 including a plurality of divided pieces 36 is prepared, and the wiring board 40 is reinforced using the stiffener 31. Each divided piece 36 of the stiffener 31 is manufactured by processing a copper plate or the like using a conventionally known processing apparatus.

  In the present embodiment, it is necessary to dispose a plurality of divided pieces 36 through the slits 39 so that the stiffener 31 has a rectangular frame shape. Here, if each of the divided pieces 36 is arranged one by one, it takes time and it becomes difficult to join the individual divided pieces 36 to an accurate position. Furthermore, if any one of the divided pieces 36 is displaced in the fixed position, a desired slit width cannot be secured. And when the slit width becomes narrow, the relaxation of thermal stress becomes insufficient. On the other hand, if the slit width is widened, the strength of the stiffener 31 cannot be sufficiently secured. For this reason, in this Embodiment, the new manufacturing method for joining the stiffener 31 which consists of several division | segmentation piece 36 correctly is employ | adopted.

  Specifically, by using an arrangement jig 90 as shown in FIGS. 12 and 13, the individual divided pieces 36 constituting the stiffener 31 are joined at accurate positions. The placement jig 90 according to the present embodiment includes a lower jig 91 and an upper jig 92. The lower jig 91 is formed with a recess 93 for storing and fixing the wiring board 40. The upper jig 92 is formed with a rectangular opening 94 in plan view, and around the opening 94, there are four housings that can be arranged in a frame shape while positioning the divided pieces 36 relative to each other. A portion 95 is formed. The opening 94 is a through hole for exposing the IC chip mounting region 23 in the wiring board 40. The accommodating portion 95 is a trapezoidal through hole having a long side and a short side, and is formed according to the shape of the stiffener 31.

  Then, in the jig placement step, the wiring board 40 with the board main surface 41 facing upward is housed in the recess 93 of the lower jig 91, and in this state, the upper side of the lower jig 91 (the board main surface of the wiring board 40). 41) and the upper jig 92 is arranged so as to overlap.

  In the bonding step, after the adhesive 30 is applied to the bonding surface 32 of each divided piece 36, each divided piece 36 is accommodated in each accommodating portion 95, and the bonding surface 32 is brought into contact with the substrate main surface 41. In this state, if the adhesive 30 is solidified by performing a heat treatment (curing) at about 150 ° C., for example, the adhesive 30 is cooled to room temperature after the heat treatment, and each divided piece 36 is formed on the substrate main surface 41. On the other hand, it is bonded and fixed via an adhesive 30. As a result, the divided pieces 36 are joined in a frame shape as a whole on the board main surface 41 of the wiring board 40. Then, after the lower jig 91 and the upper jig 92 are separated from each other, the wiring board 40 is taken out from the arrangement jig 90.

  Thereafter, the IC chip 21 is mounted on the IC chip mounting area 23 of the wiring board 40. At this time, the surface connection terminals 22 on the IC chip 21 side and the main surface side solder bumps 54 on the wiring board 40 side are aligned. Then, by heating and reflowing the main surface side solder bumps 54, the surface connection terminals 22 and the main surface side solder bumps 54 are joined, and the IC chip 21 is mounted on the wiring board 40 (see FIG. 1). .

  Therefore, according to the present embodiment, the following effects can be obtained.

  (1) In the present embodiment, by using the arrangement jig 90, the plurality of divided pieces 36 can be arranged in a frame shape as a whole while being positioned with respect to each other. A plurality of divided pieces 36 can be quickly joined at various positions. In this case, a slit 39 having a uniform slit width can be formed between the divided pieces 36 in the stiffener 31. Therefore, the strength of the wiring board 40 can be reliably increased by the stiffener 31 including the respective divided pieces 36. Further, since the stiffener 31 is completely divided by each divided piece 36, the thermal stress applied to the stiffener 31 due to the difference in thermal expansion coefficient between the stiffener 31 and the wiring board 40 can be surely relieved, and reinforcement is performed. Warpage of the wiring board 11 with material can be prevented.

  (2) In the wiring board 11 with a stiffener of the present embodiment, the stiffener 31 having a rectangular frame shape is joined on the board main surface 41 of the wiring board 40 so as to surround the periphery of the IC chip 21. The strength of the can be reliably increased.

  In addition, you may change embodiment of this invention as follows.

  In the wiring board 11 with the stiffener of the above embodiment, the stiffener 31 is formed using the four divided pieces 36 made of copper. However, a divided piece made of metal other than copper may be used, or a ceramic made piece. Alternatively, a divided piece made of resin or a divided piece made of resin may be used. Furthermore, you may use the division piece formed by affixing a metal plate or a ceramic board on the surface of the base material which consists of resin materials. Further, at least one of the divided pieces 36 constituting the stiffener 31 may be formed of a material different from that of the other divided pieces 36. Further, at least one of the divided pieces 36 may be joined using an adhesive different from that of the other divided pieces 36.

  Specifically, for example, as shown in FIG. 14, in the stiffener-equipped wiring board 11A, the divided piece 36A disposed on the right side is formed of copper, which is a metal material, and the divided piece 36B disposed on the left side is formed of a resin material. It is made of epoxy resin. In the stiffener-equipped wiring board 11A, the metal divided pieces 36A and the resin divided pieces 36B are joined using different adhesives 30A and 30B. Further, in the wiring board 11A with a stiffener, the IC chip 21 is mounted at a position shifted to the left side from the center in the wiring board 40, and the right side is insufficient in strength. Therefore, the right side is reinforced with a metal divided piece 36A. ing. On the other hand, since the difference in thermal expansion coefficient between the IC chip 21 and the wiring board 40 increases on the left side of the wiring board 40, the wiring board 40 is reinforced with resin-made segment pieces 36B that have a small difference in thermal expansion coefficient. . Further, by using the adhesives 30A and 30B suitable for the material for forming the divided pieces 36A and 36B, the divided pieces 36A and 36B can be reliably bonded. Thus, by configuring the stiffener 31A with the divided pieces 36A and 36B of different materials, it is possible to reliably prevent the wiring board 11A with a stiffener from warping.

  In the wiring board 11 with a reinforcing material of the above embodiment, the stiffener 31 is formed using a plurality of divided pieces 36 having the same shape, but the present invention is not limited to this. The stiffener 31B may be configured by using divided pieces 36C and 36D having different thicknesses as in the wiring board with reinforcing material 11B shown in FIG. In this stiffener-equipped wiring board 11B, the IC chip 21 is mounted at a position shifted to the left side from the center of the wiring board 40, and the right side strength is insufficient. For this reason, the right side of the wiring board 40 is reinforced with a thick divided piece 36C, and the left side is reinforced with a thin divided piece 36D. If the wiring board 11B with the reinforcing material is configured in this way, the wiring board 40 can be reinforced with the divided pieces 36C and 36D having different thicknesses, and the warping of the wiring board 11B with the strong material can be surely prevented. Can do. Further, for example, the width of the divided pieces arranged in the portion where the strength is insufficient in the wiring board with the reinforcing material may be increased. That is, the stiffener is formed using divided pieces having different shapes according to the warp of the wiring board 40. Also in this case, the wiring board 40 can be reliably reinforced and the warping of the wiring board 40 can be prevented.

  In the above embodiment, the divided pieces 36 constituting the stiffener 31 are bonded to the resin insulating layer 46 of the wiring board 40 using the epoxy adhesive 30, but the present invention is not limited to this. Like the wiring board 40A shown in FIG. 16, the conductive layer 51 may be bonded to the conductor layer 51 using a conductive adhesive 30C. Here, since the divided piece 36 is made of copper, which is a conductive metal material, it can be electrically connected to the conductor layer 51 of the wiring board 40 via the divided piece 36. In this case, the divided piece 36 can be used as an external terminal, which is practically preferable. The other divided pieces 36 that are not used as external terminals are bonded to the resin insulating layer 46 using the epoxy adhesive 30.

  -In above-mentioned embodiment, although the division | segmentation piece 36 which comprises the stiffener 31 is a trapezoidal member, the shape can be changed suitably. Another specific example of the divided piece 36 is shown in FIG. As shown in FIG. 17, the stiffener 31C of the reinforcing-material-attached wiring board 11C is formed in a rectangular frame shape by four divided pieces 36E having an L-shape. Also in this stiffener 31C, a slit 39A extending from the frame inner surface 37 to the frame outer surface 38 is formed. Each slit 39A is formed in a direction perpendicular to each side at the center of each side of the stiffener 31C. And when manufacturing the wiring board 11C with a reinforcing material, the arrangement | positioning jig | tool 90A as shown in FIG. 18 is used. This arrangement jig 90A also includes a lower jig 91 and an upper jig 92A. The upper jig 92A is formed with four accommodating portions 95A that can be arranged in a frame shape as a whole while positioning the divided pieces 36E relative to each other. The lower jig 91 has the same shape as that of the above embodiment shown in FIG. By using the placement jig 90A, the plurality of divided pieces 36E can be quickly joined to the correct positions on the board main surface 41 of the wiring board 40.

  The stiffeners 31, 31 </ b> A to 31 </ b> C having the same outer dimensions as the wiring board 40 are used in the wiring boards 11, 11 </ b> A to 11 </ b> C with the reinforcing material of the above embodiment, but are not limited thereto. A stiffener 31D having an outer dimension larger than that of the wiring board 40 may be used like the wiring board with reinforcing material 11D shown in FIG. The stiffener 31D is composed of four divided pieces 36F divided through the slits 39B. The stiffener 31D is joined to the wiring board 40 in a state where the outer edge portion is entirely projected in the substrate plane direction from the outer edge portion of the wiring board 40. Yes. When the wiring board 11D with the reinforcing material is configured in this manner, the outer edge portion of the wiring board 40 is relatively retracted from the outer edge portion of the stiffener 31D, and other members or the like are less likely to contact the outer edge portion of the wiring board 40. . As a result, the outer edge portion of the wiring board 40 can be reliably protected by the stiffener 31D, and the outer edge portion of the wiring board 40 can be prevented from being damaged.

  In each of the above embodiments, the slits 39, 39A, 39B formed in the stiffeners 31, 31A to 31D have a linear shape, but may be changed to a non-linear shape. A specific example is shown in FIG. A stiffener 31E of the wiring board with reinforcing material 11E shown in FIG. 20 is composed of four divided pieces 36G, and each divided piece 36G is divided through a crank-shaped slit 39C. By forming such a slit 39C in the stiffener 31E, the thermal stress applied to the stiffener 31E due to the difference in thermal expansion coefficient between the stiffener 31E and the wiring board 40 can be reliably relieved. In this case, even if the positions of the individual divided pieces 36G are shifted in order to relieve the thermal stress, a part of each divided piece 36G overlaps in the surface direction of the stiffener 31E. And the curvature of the wiring board 40 can be reliably prevented by the overlapping portions of the divided pieces 36G.

  As in the wiring board 40B shown in FIG. 21, a plane conductor layer 51A may be provided across a plurality of layers of the resin insulating layers 44 to 46 at positions corresponding to the locations where the slits 39 are formed. The plane conductor layer 51A is a dummy conductor layer that is not connected to the via conductor 57 and has no electrical function. In the stiffener-provided wiring substrate 11F of FIG. 21, the portion of the stiffener 31 where the slit 39 is formed has low rigidity, but the portion of the wiring substrate 40B provided with a plane-like conductor layer 51A reinforces the portion of low rigidity. can do. For this reason, the rigidity of the wiring board 11F with the reinforcing material can be sufficiently ensured.

  -Although the stiffeners 31 and 31A-31F of each said embodiment were comprised by the four division | segmentation pieces 36 and 36A-36G, the number of division | segmentation pieces can be changed suitably.

  Next, the technical ideas grasped by the embodiment described above are listed below.

  (1) It has a substrate main surface and a substrate back surface, has a structure in which a plurality of resin insulation layers and a plurality of conductor layers are laminated, and a plurality of main surface side connection terminals to which chip components can be connected are the main substrate A plate-like wiring board disposed on the surface, and a frame-like reinforcement as a whole in a plan view, which is joined to the substrate main surface side and is composed of a plurality of divided pieces and exposes the plurality of main surface side connection terminals. And a jig having a plurality of accommodating portions that can be arranged in a frame shape as a whole while positioning the plurality of divided pieces relative to each other. A jig arranging step of arranging the plurality of divided pieces in the plurality of accommodating portions, and a joining step of joining the plurality of divided pieces to the substrate main surface, A lower jig having a recess for storing and fixing the wiring board, and an upper surface of the lower jig Is Kasaneawaru so arranged, the manufacturing method of the reinforcing member with the wiring board, characterized in that it comprises an upper jig having a plurality of accommodating portions.

  (2) In the technical idea (1), at least one divided piece of the plurality of divided pieces is bonded using an adhesive different from the other divided pieces, and the reinforcing material-attached wiring A method for manufacturing a substrate.

  (3) In the technical idea (1) or (2), at least one divided piece of the plurality of divided pieces is formed to include a conductive metal material and to the conductor layer of the wiring board. A method for manufacturing a wiring board with a reinforcing material, wherein the wiring board is bonded using a conductive adhesive.

  (4) In the technical idea (1), a method of manufacturing a wiring board with a reinforcing material, characterized in that divided pieces having different shapes are joined to the wiring board according to warping of the wiring board.

  (5) In any one of the technical ideas (1) to (4), an outer dimension of the reinforcing material is set larger than an outer dimension of the wiring board, and an outer edge portion of the reinforcing material is an outer edge portion of the wiring board. A method of manufacturing a wiring board with a reinforcing material, wherein the reinforcing material is joined to the wiring board in a state of projecting in an overall direction in the plane of the board.

  (6) In any one of the technical ideas (1) to (5), in the reinforcing material, the slit formed between the divided pieces has a linear shape. Method.

  (7) In any one of the technical ideas (1) to (5), in the reinforcing material, the slit formed between the divided pieces has a crank shape. Method.

  (8) In the technical idea (6) or (7), a plane-like conductor layer is disposed over a plurality of layers at a position corresponding to the position where the slit is formed in the wiring board. Manufacturing method of wiring board with reinforcing material.

11, 11A to 11F: Wiring board with stiffener as wiring board with reinforcing material 21 ... IC chip 31, 31A to 31E as chip component ... Stiffeners 36, 36A to 36G as reinforcing material 40, 40A, 40B ... Wiring board 41 ... substrate main surface 42 ... substrate back surface 43-46 ... resin insulating layer 51 ... conductor layer 52 ... terminal pad as main surface side connection terminal 70 ... support substrate 71 ... base resin insulating layer 72 as base resin sheet 72 ... Laminated metal sheet bodies 73, 74 ... copper foil as metal foil 75 ... resin insulating base material as resin insulating sheet 80 ... laminated body 81 ... wiring laminated portion 82 ... peripheral portion 92,92A ... upper jig 95 as jig , 95A ... Accommodating section

Claims (4)

A substrate main surface and a substrate back surface, having a structure in which a plurality of resin insulation layers and a plurality of conductor layers are stacked, and a plurality of main surface side connection terminals to which chip components can be connected are on the substrate main surface An arranged plate-like wiring board;
Manufacturing of a wiring board with a reinforcing material, which is bonded to the main surface side of the substrate, exposes the plurality of main surface side connection terminals, and includes a reinforcing material composed of a plurality of divided pieces that form a frame shape as a whole in plan view. A method,
A jig arranging step of arranging a jig provided with a plurality of accommodating portions that can be arranged in a frame shape as a whole while positioning the plurality of divided pieces on the substrate main surface side;
A method of manufacturing a wiring board with a reinforcing material, comprising: a joining step of housing the plurality of divided pieces in the plurality of housing portions and joining the plurality of divided pieces to the substrate main surface.   2. The method of manufacturing a wiring board with a reinforcing material according to claim 1, wherein at least one of the plurality of divided pieces is formed of a material different from that of the other divided pieces.   2. The method of manufacturing a wiring board with a reinforcing material according to claim 1, wherein at least one of the plurality of divided pieces has a thickness different from that of the other divided pieces. The plate-like wiring board is
A base resin sheet forming step of forming a base resin sheet on a support substrate used for reinforcement during production;
A metal sheet body arranging step of arranging a laminated metal sheet body in close contact with the two metal foils in a peelable state on the base resin sheet;
A metal sheet body seal is provided, wherein a resin insulating sheet to be the resin insulating layer is disposed so as to wrap the laminated metal sheet body, and the laminated metal sheet body is sealed between the resin insulating sheet and the base resin sheet. Stop process,
On the resin insulation sheet encapsulating the laminated metal sheet body, a wiring pattern to be the conductor layer and a resin insulation sheet to be the resin insulation layer are alternately laminated to form a wiring laminate to be the wiring board. A laminated body forming step of forming a laminated body including a portion on the laminated metal sheet body;
A peripheral part excision step of removing the peripheral part by cutting the laminated body together with the support substrate along a boundary between the wiring laminated part and the peripheral part;
A peeling step of peeling the wiring laminated portion and the support substrate at the interface of the laminated metal sheet body;
The metal foil on the surface of the wiring laminated portion is patterned and manufactured through each step of a connection terminal forming step of forming a plurality of main surface side connection terminals on the substrate main surface. The manufacturing method of the wiring board with a reinforcing material of any one of Claims 1 thru | or 3.

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