JP6324669B2 - Multilayer wiring board and manufacturing method thereof - Google Patents

Description

  The present invention relates to a multilayer wiring board comprising a ceramic wiring board having a substrate main surface and a substrate back surface, and a wiring structure laminated on the substrate main surface of the ceramic wiring substrate and having a resin insulating layer, a wiring layer, and a via conductor. And a manufacturing method thereof.

  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 in an array on the bottom surface of an IC chip. In order to inspect electronic components such as the IC chip, a multilayer wiring board for inspecting electronic components is used.

  As a multilayer wiring board for electronic component inspection, there is a multilayer wiring board in which a wiring structure composed of a plurality of resin insulating layers and a plurality of wiring layers is laminated on the upper side of a ceramic wiring board formed by laminating a plurality of ceramic insulating layers. It has been put into practical use. In this multilayer wiring board, each resin insulation layer and each ceramic insulation layer are provided with via conductors penetrating the insulation layers, and electrical connection between the layers is achieved by the via conductors.

  When the multilayer wiring board is manufactured, a wiring structure composed of each resin insulating layer is pressure-bonded to the ceramic wiring board by heating and pressing with a plurality of resin insulating layers arranged on the ceramic wiring board. . At the time of this pressure bonding, the resin insulating layer moves as the viscosity decreases due to heating, and the wiring layer is likely to be deformed or misaligned. In order to avoid this problem, a multilayer wiring board in which a non-through via conductor (dummy via conductor) is formed in a resin insulating layer has been proposed (for example, see Patent Document 1). In this multilayer wiring board, since the movement of the resin insulating layer in the planar direction is suppressed by the plurality of non-through via conductors, deformation and misalignment of the wiring layer are prevented, so that problems such as disconnection are avoided.

JP2012-93103A

  By the way, in the conventional multilayer wiring board disclosed in Patent Document 1, it is necessary to form a plurality of non-penetrating via conductors in the resin insulating layer in order to prevent misalignment of the resin insulating layers. In this multilayer wiring board, if the arrangement space for each non-through via conductor is secured, the wiring layers cannot be arranged at high density. Furthermore, when a non-through via conductor is provided, it may be easy to pick up electrical noise, and there is a concern that the electrical characteristics of the multilayer wiring board will deteriorate.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a highly reliable multilayer wiring board by laminating a wiring structure on a ceramic wiring board with high positional accuracy. Another object is to provide a method for manufacturing a multilayer wiring board suitable for manufacturing the multilayer wiring board.

  And as means (means 1) for solving the above-mentioned problems, a resin insulating layer having a pair of main surfaces and having a via hole penetrating between the main surfaces, at least one of the resin insulating layers A wiring layer disposed on the main surface; a wiring structure having a via conductor provided in the via hole and electrically connected to the wiring layer; a substrate main surface and a substrate back surface; And a through-hole conductor portion that conducts between the back surfaces of the substrate and a ceramic wiring substrate on which the wiring structure is laminated on the main surface of the substrate, wherein the resin insulating layer A first resin layer made of a curable resin and a second resin layer made of a thermoplastic resin that is laminated on the first resin layer and forms at least one of the main surfaces. The center is high and the outer periphery of the board is low There are multi-layer wiring board, wherein a difference in height which is provided with.

  Therefore, according to the invention described in Means 1, since the substrate main surface is provided with a height difference in which the central portion of the substrate is a high place and the peripheral portion of the substrate is a low place, the substrate main surface of the ceramic wiring board is provided. When the wiring structure is laminated by heating and pressing, tension (centrifugal tension in the plane direction of the wiring structure) is applied to the resin insulating layer. For this reason, the movement of the plane direction accompanying the viscosity fall of the resin insulating layer by heating can be prevented. Therefore, the wiring structure can be laminated with high positional accuracy on the ceramic wiring substrate, and the problem that the wiring is disconnected can be avoided. Further, in the multilayer wiring board of the present invention, it is not necessary to provide a non-penetrating via conductor (dummy via conductor) as in the prior art, so that it is possible to increase the density of wiring while maintaining good electrical characteristics. it can.

  There may be a stepped portion at the boundary between the high place and the low place on the main surface of the substrate. In this case, the shift in the planar direction of the resin insulating layer can be reliably prevented by the edge of the stepped portion. In addition, since the contact area between the ceramic wiring board and the resin insulating layer increases by the height difference of the stepped portion, the connection strength between the ceramic wiring board and the wiring structure can be increased.

  The stepped portion on the main surface of the substrate may be disposed on the outer peripheral side of the region where the wiring layer and the via conductor are formed. In this way, the step portion can be reliably formed without affecting the electrical characteristics of the multilayer wiring board, and the reliability of the multilayer wiring board can be ensured.

  The height difference on the substrate main surface may be set to be larger than the thickness of the second resin layer and smaller than the thickness of the resin insulating layer. Here, if the height difference is smaller than that of the second resin layer, the height difference is absorbed by the second resin layer softened during heating, so that the effect of stacking misalignment due to the height difference cannot be sufficiently obtained. Further, if the height difference is larger than that of the resin insulating layer, the flatness required on the surface of the multilayer wiring board may not be ensured. Therefore, if the height difference is set on the main surface of the substrate so as to be larger than the thickness of the second resin layer and smaller than the thickness of the resin insulating layer, it is possible to reliably prevent the resin insulating layer from being displaced during lamination. A highly reliable multilayer wiring board can be obtained.

  A height on the main surface of the substrate is a flat surface perpendicular to the thickness direction of the ceramic wiring substrate, and a substrate-side wiring layer connected to the through conductor is formed thereon. In this case, a substrate-side wiring layer having a uniform thickness can be formed with high positional accuracy, and disconnection between the ceramic wiring substrate and the wiring structure can be reliably prevented.

  The multilayer wiring board may be an IC inspection apparatus substrate. In this case, since the wiring layer in the IC inspection apparatus substrate can be formed with high accuracy, it is possible to reliably inspect IC chips in which a large number of terminals are densely arranged.

  As the resin insulation layer (the first resin layer and the second resin layer), a polyimide-based resin material is usually used, but it may be formed using a resin other than the polyimide-based resin, and has an insulating property and heat resistance. Further, it can be appropriately selected in consideration of moisture resistance and the like. In addition, as the first resin layer of the resin insulation layer, a composite material of resin and organic fibers such as glass fibers (glass woven fabric or glass nonwoven fabric) or polyamide fibers, or a three-dimensional network fluorine-based such as continuous porous PTFE A resin-resin composite material in which a resin base material is impregnated with a thermosetting resin may be used.

  The wiring layer is mainly made of copper, and is formed by a known method such as a subtractive method, a semi-additive method, or a full additive method. Specifically, for example, techniques such as etching of copper foil, electroless copper plating, or electrolytic copper plating are applied. It is also possible to form a wiring layer by etching after forming a thin film by a technique such as sputtering or CVD, or to form a wiring layer by printing a conductive paste or the like.

  Further, as another means (means 2) for solving the above-mentioned problem, there is provided a method of manufacturing the multilayer wiring board according to means 1, wherein a resin insulating layer on which the wiring layer and the via conductor are formed is provided. A wiring structure preparing step for preparing a wiring structure having a ceramic wiring substrate preparing step for preparing a ceramic wiring substrate provided with the through conductors, and providing the height difference on the main surface of the ceramic wiring substrate. A step of applying a difference in height, and a step of laminating the wiring structure to the main surface of the substrate by applying heat and pressure in a state where the wiring structure is disposed on the main surface of the substrate where the height difference exists. There is a manufacturing method of a multilayer wiring board characterized by including:

  Therefore, according to the invention described in the means 2, after the height difference is provided on the main surface of the ceramic wiring substrate in the height difference applying step, the stacking step is performed. In this laminating process, heating and pressurization are performed in a state where the wiring structure is disposed on the substrate main surface where there is a height difference, and the wiring structure is pressure-bonded to the substrate main surface. At this time, since tension is applied to the resin insulation layer of the wiring structure, movement in the plane direction due to a decrease in the viscosity of the resin insulation layer is prevented, and the wiring structure is accurately laminated on the ceramic wiring substrate. Can do.

  In the stacking step, the wiring structures may be collectively bonded to the main surface of the substrate by performing heat and pressure in a state where a plurality of wiring structures are arranged on the main surface of the substrate having a height difference. If it does in this way, compared with the case where a plurality of wiring structures are crimped one by one, a manufacturing process can be simplified and a multilayer wiring board can be manufactured in a short time. A plurality of wiring structures may be pressure-bonded one by one on the main surface of the substrate where there is a height difference. In this case, the work period of the multilayer wiring board is lengthened, but it is possible to reliably prevent the resin insulating layer from being displaced during lamination.

  In the elevation difference providing step, the elevation difference may be provided by removing the ceramic material on the outer periphery of the substrate on the substrate main surface of the ceramic wiring substrate that has undergone the firing step. In this way, a height difference of a predetermined dimension can be accurately and easily formed on the main surface of the ceramic wiring board. Specifically, when the stepped portion is formed by removing the ceramic material on the outer periphery of the substrate, the stepped portion with an edge can be accurately formed, thus reliably preventing the displacement of the resin insulating layer during lamination. can do.

  In the elevation difference providing step, the substrate main surface of the ceramic wiring substrate that has undergone the firing step is surface-polished in advance, and then the ceramic material on the outer peripheral portion of the substrate is removed from the surface-polished substrate main surface to provide a height difference May be. In this way, the height difference on the main surface of the substrate can be accurately provided. In addition, since the substrate main surface subjected to surface polishing becomes a flat surface, the substrate-side wiring layer connected to the through conductor portion can be formed on the substrate main surface with a uniform thickness with high positional accuracy. In addition, since the lower portion of the main surface of the substrate has a larger surface roughness than the higher portion, the lower portion of the outer periphery of the substrate can surely prevent the resin insulating layer from being displaced during lamination.

  In the elevation difference applying step, the ceramic material on the outer periphery of the substrate is removed by laser trimming, etching, or polishing. In other words, according to the present invention, an optimum method is selected from laser trimming, etching and polishing according to the type of ceramic material and the shape and size of the ceramic wiring substrate, and the ceramic material on the outer periphery of the substrate is removed by this method. To do. In this way, by removing the ceramic material on the outer peripheral portion of the substrate by an optimal method, it is possible to reliably provide a height difference on the main surface of the substrate.

Sectional drawing which shows schematic structure of the multilayer wiring board in this Embodiment. Explanatory drawing which shows the wiring structure preparation process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the wiring structure preparation process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the wiring structure preparation process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the ceramic wiring board preparation process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the ceramic wiring board preparation process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the ceramic wiring board preparation process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the ceramic wiring board preparation process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the height difference provision process in the manufacturing method of a multilayer wiring board. Explanatory drawing which shows the ceramic wiring board of another embodiment which does not provide a level | step-difference part in a board | substrate main surface.

  Hereinafter, an embodiment in which the present invention is embodied in a multilayer wiring board will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a schematic configuration of a multilayer wiring board according to the present embodiment.

  A multilayer wiring substrate 10 shown in FIG. 1 is a substrate for an IC inspection apparatus for performing an electrical inspection of an IC chip. The multilayer wiring board 10 includes a plurality (two in this embodiment) of wiring structures 20 and 21 stacked in the thickness direction, and a ceramic wiring board 40 provided on the lower layer side of the wiring structure 21. The multilayer wiring board 10 is a board having a vertical and horizontal length of about 10 cm and a thickness of about 4 mm. When used, the main surface 11 (upper surface in FIG. 1) of the multilayer wiring board 10 is directed toward an IC chip to be inspected. Arranged.

  The upper wiring structure 20 includes a resin insulating layer 22, a wiring layer 24 and a via conductor 26, and the lower wiring structure 21 includes a resin insulating layer 23, a wiring layer 25 and a via conductor 26. Each resin insulating layer 22, 23 has a pair of main surfaces 27, 28, and a via hole 29 penetrating between the main surfaces 27, 28 is formed. The wiring layer 24 is disposed on the main surface 27 (the upper surface in the present embodiment) of the resin insulating layer 22. The wiring layer 25 is disposed on the main surface 27 of the resin insulating layer 23. The via conductor 26 is provided in the via hole 29 and is electrically connected to the wiring layers 24 and 25.

  The resin insulating layers 22 and 23 are insulating layers made of polyimide resin, for example. Specifically, the resin insulating layers 22 and 23 are laminated on both surfaces of the first resin layer 31 and the first resin layer 31, and the second resin layer 32 forming the main surfaces 27 and 28 of the resin insulating layers 22 and 23. It is comprised by. In the present embodiment, the first resin layer 31 constituting the resin insulating layers 22 and 23 is made of a polyimide-based thermosetting resin and has a thickness of about 20 μm. The second resin layer 32 is made of a polyimide-based thermoplastic resin and has a thickness of about 2.5 μm. That is, the resin insulating layers 22 and 23 are about 25 μm. The wiring layers 24 and 25 are conductor layers made of, for example, copper, and the thickness thereof is about 5 μm. The via holes 29 and the via conductors 26 of the wiring structures 20 and 21 have a circular cross section, and the inner diameter of the via holes 29 and the outer diameter of the via conductors 26 are about 50 μm.

  A plurality of main surface side terminals 35 constituting the wiring layer 24 are formed in an array at the central portion of the main surface 11 of the multilayer wiring board 10 (the upper surface of the wiring structure 20). The main surface side terminal 35 has a circular cross section, and its diameter is set to about 60 μm, for example.

  The ceramic wiring substrate 40 has a substrate main surface 41 and a substrate back surface 42, and the wiring structures 20 and 21 are laminated on the substrate main surface 41. A plurality of ceramic insulating layers 43, 44, 45 and a plurality of conductor layers 46 are laminated on the ceramic wiring substrate 40. The ceramic insulating layers 43 to 45 are, for example, alumina sintered bodies, and the conductor layer 46 is, for example, a metallized layer of tungsten, molybdenum, or an alloy thereof. In the ceramic wiring substrate 40, each ceramic insulating layer 43 to 45 has a through hole 48 penetrating in the thickness direction, and a via conductor 49 connected to the conductor layer 46 is formed in the through hole 48. ing. Each through-hole 48 has a circular cross section, and the inner diameter thereof is about 60 μm. Each via conductor 49 also has a circular cross section, and the outer diameter thereof is about 60 μm. The via conductor 49 is made of a metallized layer of tungsten, molybdenum, or an alloy thereof, like the conductor layer 46. Each conductor layer 46 and each via conductor 49 function as a through conductor portion that conducts between the substrate main surface 41 and the substrate back surface 42.

  On the substrate back surface 42 of the ceramic wiring substrate 40 (the back surface 12 of the multilayer wiring substrate 10), a plurality of back surface side terminals 50 are formed in an array over almost the entire area. Each back terminal 50 has a circular cross section, and the diameter of the back terminal 50 is set to about 1.0 mm. In addition, a thin-film conductor layer 51 is formed in the central portion of the substrate main surface 41. The conductor layer 51 is a substrate-side wiring layer made of titanium and / or copper.

  Each back-side terminal 50 of the ceramic wiring board 40 is connected to the via conductor 26 of the wiring structure 21 via the via conductor 49 and the conductor layers 46 and 51, and further the wiring layer 25 and the wiring structure 20 of the wiring structure 21. The main surface side terminal 35 is connected through the via conductor 26.

  Further, in the ceramic wiring substrate 40, the substrate main surface 41 is provided with a height difference with the substrate central portion 54 as a high place and the substrate outer peripheral portion 55 as a low place. More specifically, on the substrate main surface 41 of the ceramic wiring substrate 40, a stepped portion 56 is formed at the boundary between the substrate central portion 54 that is a high place and the substrate outer peripheral portion 55 that is a low place. The step portion 56 is disposed on the outer peripheral side of the region where the wiring layer 25 and the via conductor 26 of the wiring structure 21 are formed. The height difference of the stepped portion 56 is about 10 μm, and is set to be larger than the thickness of the second resin layer 32 of the resin insulating layers 22 and 23 and smaller than the thickness of the resin insulating layers 22 and 23. . Further, the height of the substrate main surface 41 is a flat surface perpendicular to the thickness direction of the ceramic wiring substrate 40, and a conductor layer 51 (substrate-side wiring layer) connected to the via conductor 26 is formed thereon. ing.

  In the multilayer wiring board 10, the height difference in the substrate main surface 41 of the ceramic wiring substrate 40 is absorbed by the resin insulating layers 22 and 23 of the wiring structures 20 and 21, and the height difference between the central portion and the outer peripheral portion on the main surface 11. The difference is smaller than the height difference on the substrate main surface 41. That is, the height difference on the upper surface of each wiring structure 20, 21 becomes smaller toward the upper layer side.

  Next, a method for manufacturing the multilayer wiring board 10 in the present embodiment will be described.

  First, a wiring structure preparation process is performed. Specifically, as shown in FIG. 2, a copper foil 63 that becomes the wiring layers 24 and 25 is formed on one main surface 27 (upper surface in FIG. 2) of the resin insulating material 61 that becomes the resin insulating layers 22 and 23. The formed resin film 64 with copper foil is prepared and cut into predetermined dimensions. The resin insulating material 61 includes a first resin layer 31 made of a polyimide-based thermosetting resin, and a second resin layer 32 made of a polyimide-based thermoplastic resin disposed on both surfaces of the first resin layer 31. Composed. A copper foil 63 having a thickness of 5 μm is attached to the upper surface 27 side of the resin insulating material 61.

  Next, the via hole 29 which penetrates the resin insulating material 61 of the resin film 64 with copper foil and the copper foil 63 is formed by laser processing. Then, using a paste printing filling device (not shown), as shown in FIG. 3, the via hole 29 of the resin film 64 is filled with a conductive paste (copper paste) mainly composed of copper powder, and a via conductor is formed. 26 is formed. Thereafter, it is heated at 150 ° C. for 1 hour.

  Then, a photosensitive dry film is attached on the copper foil 63 formed on the upper surface 27 of the resin film 64. Further, an exposure mask in which a wiring pattern of the wiring layer 24 (main surface side terminal 35) is previously formed is disposed on the dry film. Next, after the dry film is exposed through an exposure mask, development is performed, and an etching resist for etching the copper foil 63 is patterned. Further, a photosensitive dry film is also attached to the main surface 28 (lower surface in FIG. 3) side of the resin film 64, and an etching resist is formed so as to cover the entire lower surface 28 by the exposure and development described above.

  Thereafter, a portion of the copper foil 63 exposed from the resist pattern of the etching resist is removed by etching to form the main surface side terminal 35 as the wiring layer 24. Thereafter, by contacting with the stripping solution, the etching resist remaining on the main surface side terminal 35 is removed, and the etching resist on the lower surface 28 side is removed.

  As a result, as shown in FIG. 4, the wiring structure 20 having the resin insulating layer 22, the wiring layer 24 (main surface side terminal 35), and the via conductor 26 is formed. Moreover, the wiring structure 21 having the resin insulating layer 23, the wiring layer 25, and the via conductor 26 is formed by performing the above-described steps in the same manner.

  Next, a ceramic wiring board preparation step is performed. Specifically, a plurality of green sheets are formed using a ceramic material mainly composed of alumina powder. Then, as shown in FIG. 5, laser processing is performed on the plurality of green sheets 71 to form a plurality of through holes 48 at predetermined positions. The through hole 48 may be formed by punching, drilling, or the like.

  Thereafter, using a conventionally known paste printing apparatus (not shown), the through holes 48 of each green sheet 71 are filled with a conductive paste (for example, tungsten paste) to form an unfired via conductor 49. Further, the conductive paste 46 is printed by using a conventionally known paste printing apparatus to form the unfired conductor layer 46 and the back-side terminal 50 (see FIG. 6). The order of filling and printing of the conductive paste may be reversed.

  Then, after the conductive paste is dried, the plurality of green sheets 71 are stacked and arranged, and a pressing force is applied in the sheet stacking direction, whereby the green sheets 71 are pressed and integrated to form a ceramic laminate 73. (See FIG. 7). Next, the ceramic laminate 73 is degreased and fired at a predetermined temperature for a predetermined time (firing step). As a result, the alumina of the green sheet 71 and the tungsten in the paste are simultaneously sintered, and the ceramic wiring substrate 40 is formed.

  And the board | substrate main surface 41 of the ceramic wiring board 40 which passed through the sintering process is surface-polished. Next, after sputtering titanium and copper to form a thin film on the substrate main surface 41, exposure and development are performed to form a thin film connected to the via conductor 49 at the substrate central portion 54 of the substrate main surface 41. A conductor layer 51 (substrate-side wiring layer) is formed (see FIG. 8).

  Further, as shown in FIG. 9, the stepped portion 56 is formed on the substrate main surface 41 by removing the ceramic material of the substrate outer peripheral portion 55 by laser trimming to provide a height difference (a height difference providing step). As a result, a low portion is formed in a frame shape (square frame shape) along the substrate outer peripheral portion 55 on the substrate main surface 41 of the ceramic wiring substrate 40. The ceramic wiring board 40 is prepared by performing the above steps. Since the surface of the substrate outer peripheral portion 55 which is a low place on the substrate main surface 41 is formed with fine irregularities by laser trimming, the low portion (substrate outer peripheral portion 55) of the substrate main surface 41 is a high place (the central portion of the substrate). The surface roughness is larger than 54).

Thereafter, 75 kgf / w while heating to a temperature of about 350 ° C. in a state where a plurality of wiring structures 20 and 21 shown in FIG. Pressurization is performed at a pressure of about cm ² (lamination step). Here, since the step portion 56 is provided in the substrate outer peripheral portion 55 on the substrate main surface 41, centrifugal tension (tension) acts in the planar direction of the wiring structures 20 and 21, and in this state, The wiring structures 20 and 21 are heated and pressurized. By performing this heating and pressurization, the second resin layer 32 of the resin insulating layers 22 and 23 softens and functions as an adhesive layer, and the wiring structures 20 and 21 are collectively pressure-bonded onto the ceramic wiring substrate 40. Is done. As a result, the multilayer wiring board 10 in which the wiring structures 20 and 21 and the ceramic wiring board 40 are integrated is manufactured.

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

  (1) In the multilayer wiring substrate 10 of the present embodiment, the substrate main surface 41 of the ceramic wiring substrate 40 is provided with a height difference with the substrate central portion 54 as a high place and the substrate outer peripheral portion 55 as a low place. Yes. In this case, when the wiring structures 20 and 21 are laminated by heating and pressing on the substrate main surface 41, centrifugal tension (tension) is applied in the plane direction of the wiring structures 20 and 21 (resin insulating layers 22 and 23). ) Is added. For this reason, the movement of the plane direction accompanying the viscosity fall of the resin insulating layers 22 and 23 by heating can be prevented. Therefore, the wiring structures 20 and 21 can be laminated with high positional accuracy on the ceramic wiring substrate 40, and the problem of the wiring being disconnected can be avoided. Further, in the multilayer wiring board 10 of the present invention, it is not necessary to provide a non-penetrating via conductor (dummy via conductor) as in the prior art, so that the wiring density can be increased while maintaining good electrical characteristics. be able to.

  (2) In the multilayer wiring board 10 of the present embodiment, a stepped portion 56 exists on the substrate main surface 41 of the ceramic wiring substrate 40 at the boundary between the substrate central portion 54 and the substrate outer peripheral portion 55. In this case, the deviation in the planar direction of the resin insulating layer 23 can be reliably prevented by the edge of the stepped portion 56. Further, since the contact area between the ceramic wiring substrate 40 and the resin insulating layer 23 increases by the height difference of the step portion 56, the connection strength between the ceramic wiring substrate 40 and the wiring structure 21 can be increased.

  (3) In the multilayer wiring substrate 10 of the present embodiment, the stepped portion 56 of the substrate main surface 41 is disposed on the outer peripheral side of the region where the wiring layers 24 and 25 and the via conductor 26 are formed. In this way, the step portion 56 can be reliably formed without affecting the electrical characteristics of the multilayer wiring board 10, and the reliability of the multilayer wiring board 10 can be ensured.

  (4) In the multilayer wiring substrate 10 of the present embodiment, the height difference of the substrate main surface 41 is set to be larger than the thickness of the second resin layer 32 and smaller than the thickness of the resin insulating layers 22 and 23. ing. Here, if the height difference is smaller than that of the second resin layer 31, the height difference is absorbed by the second resin layer 31 that is softened during heating, so that the effect of stacking misalignment due to the height difference cannot be sufficiently obtained. Further, if the height difference is larger than that of the resin insulating layers 22 and 23, the flatness required for the main surface 11 of the multilayer wiring board 10 may not be ensured. Accordingly, when the above-described height difference is set, it is possible to reliably prevent the resin insulating layers 22 and 23 from being displaced during lamination, and to obtain a highly reliable multilayer wiring board 10.

  (5) In the multilayer wiring substrate 10 of the present embodiment, the height of the substrate main surface 41 is a flat surface perpendicular to the thickness direction of the ceramic wiring substrate 40, and a conductor connected to the via conductor 49 thereon. Layer 51 is formed. In this case, since the conductor layer 51 having a uniform thickness can be formed with high positional accuracy, disconnection between the ceramic wiring substrate 40 and the wiring structure 21 can be reliably prevented.

  (6) In the multilayer wiring board 10 of the present embodiment, since the main surface side terminals 35 are formed with high positional accuracy, the IC chips in which a large number of terminals are densely arranged in an array are reliably inspected. be able to.

  (7) In the case of the present embodiment, in the laminating step, heating and pressing are performed in a state in which a plurality of wiring structures 20 and 21 are arranged on the substrate main surface 41 of the ceramic wiring substrate 40 having a height difference. Thus, the wiring structures 20 and 21 are collectively bonded to the substrate main surface 41. In this way, the manufacturing process can be simplified and the multilayer wiring board 10 can be manufactured in a short time as compared with the case where the plurality of wiring structures 20 and 21 are bonded to the substrate main surface 41 one by one. be able to.

  (8) In the case of the present embodiment, the height difference is provided on the substrate main surface 41 of the ceramic wiring substrate 40 that has undergone the firing process by removing the ceramic material of the substrate outer peripheral portion 55. In this way, a height difference of a predetermined dimension can be accurately and easily formed on the substrate main surface 41 of the ceramic wiring substrate 40. Specifically, since the stepped portion 56 with an edge can be accurately formed, it is possible to reliably prevent the positional displacement of the resin insulating layer 23 during lamination.

  (9) In the case of the present embodiment, an elevation difference applying step is performed after the surface of the substrate main surface 41 of the ceramic wiring substrate 40 is polished, and the substrate main surface 41 is provided with an elevation difference. In this way, the height difference in the substrate main surface 41 can be accurately provided. Further, since the substrate main surface 41 subjected to the surface polishing becomes a flat surface, the conductor layer 51 connected to the via conductor 49 can be formed on the substrate main surface 41 with a uniform thickness with high positional accuracy. Further, since the surface roughness of the low part of the substrate main surface 41 is larger than that of the high part, the positional deviation of the resin insulating layer 23 can be reliably prevented by the substrate peripheral part 55 which is the low part.

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

  In the multilayer wiring board 10 of the above embodiment, a difference in level is provided by forming the stepped portion 56 at the boundary between the substrate central portion 54 and the substrate outer peripheral portion 55 in the substrate main surface 41 of the ceramic wiring substrate 40. However, the present invention is not limited to this. For example, as shown in FIG. 10, a difference in height is provided by removing the ceramic material from the substrate central portion 54 toward the substrate outer peripheral portion 55 on the substrate main surface 41 of the ceramic wiring substrate 40A. May be. Even when the main surface 41 is thus provided with a height difference, tension is applied in the planar direction of the wiring structures 20 and 21 (resin insulating layers 22 and 23) in the stacking process. Lamination displacement can be prevented.

  In the multilayer wiring board 10 of the above-described embodiment, the height difference applying step is performed after surface polishing of the substrate main surface 41 of the ceramic wiring substrate 40. However, after the height difference applying step, the height of the substrate main surface 41 is increased. Surface polishing may be performed on the spot.

  In the above embodiment, the multilayer wiring board 10 is manufactured while leaving the substrate outer peripheral portion 55 with the stepped portion 56, but the substrate outer peripheral portion with the stepped portion 56 is obtained by performing a cutting step after the above-described lamination step. 55 may be cut and removed to manufacture a multilayer wiring board.

  The multi-layer wiring board 10 of the above embodiment is one in which two wiring structures 20 and 21 are laminated on the ceramic wiring board 40, but in addition to this, one wiring structure may be laminated. Three or more wiring structures may be stacked.

  In the multilayer wiring board 10 of the above embodiment, the stepped portion 56 that gives a height difference on the substrate main surface 41 is formed in a rectangular shape, but has other shapes such as a circular shape, an elliptical shape, and a polygonal shape. A stepped portion may be formed. Further, in order to form a height difference in the substrate main surface 41, a plurality of step portions may be provided, or irregularities having different heights may be provided.

  In the multilayer wiring board 10 of the above-described embodiment, an alumina sintered body is used as the ceramic insulating layers 43 to 45, but is not limited thereto. For example, glass-ceramic other than alumina may be used. When glass-ceramic is used, the conductor layer 46 and the via conductor 49 are made of silver, copper, or an alloy thereof.

  In the above embodiment, the present invention is embodied in the multilayer wiring board 10 for the IC inspection apparatus. However, the present invention may be embodied in a multilayer wiring board used for other purposes.

  Next, in addition to the technical ideas described in the claims, the technical ideas grasped by the embodiments described above are listed below.

  (1) The multilayer wiring board according to means 1, wherein the low portion has a surface roughness larger than that of the high portion.

  (2) A method for manufacturing a multilayer wiring board according to means 2, wherein the multilayer wiring board is a substrate for an IC inspection apparatus.

  (3) The method for manufacturing a multilayer wiring board according to means 2, wherein, in the height difference applying step, the ceramic material on the outer periphery of the substrate is removed by laser trimming, etching, or polishing.

  (4) The method for manufacturing a multilayer wiring board according to (2), wherein in the laminating step, heating and pressing are performed in a state where centrifugal tension is applied in a planar direction of the wiring structure.

DESCRIPTION OF SYMBOLS 10 ... Multilayer wiring board 20, 21 ... Wiring structure 22, 23 ... Resin insulation layer 24, 25 ... Wiring layer 26, 49 ... Via conductor 27, 28 ... Main surface 29 ... Via hole 31 ... 1st resin layer 32 ... 1st 2 resin layers 40, 40A ... ceramic wiring substrate 41 ... substrate main surface 42 ... substrate back surface 46 ... conductor layer as through conductor portion 51 ... conductor layer as substrate side wiring layer 54 ... substrate center portion 55 ... substrate outer peripheral portion 56 ... Step

Claims (8)

A resin insulating layer having a pair of main surfaces and having via holes formed between the main surfaces, a wiring layer disposed on at least one of the main surfaces of the resin insulating layer, and the via holes A wiring structure having a via conductor provided and electrically connected to the wiring layer;
A ceramic wiring substrate having a substrate main surface and a substrate back surface, provided with a through conductor portion for conducting between the substrate main surface and the substrate back surface, and wherein the wiring structure is laminated on the substrate main surface. A multilayer wiring board,
The resin insulation layer is composed of a first resin layer made of a thermosetting resin and a second resin layer made of a thermoplastic resin laminated on the first resin layer and forming at least one of the main surfaces,
The substrate main surface is provided with a height difference in which the central portion of the substrate is a high place and the peripheral portion of the substrate is a low place ,
A multilayer wiring board , wherein a step portion exists at a boundary between the high place and the low place . 2. The multilayer wiring board according to claim 1 , wherein the stepped portion is disposed closer to an outer peripheral portion than a region where the wiring layer and the via conductor are formed. The height difference, the multilayer wiring board according to claim 1 or 2, characterized in that it is set to be smaller than the thickness of the large and the resin insulating layer than a thickness of the second resin layer. The height of the main surface of the substrate is a flat surface perpendicular to the thickness direction of the ceramic wiring substrate, and a substrate-side wiring layer connected to the through conductor is formed thereon. The multilayer wiring board according to any one of claims 1 to 3 . A method for producing the multilayer wiring board according to any one of claims 1 to 4 ,
A wiring structure preparation step of preparing a wiring structure having a resin insulating layer in which the wiring layer and the via conductor are formed;
A ceramic wiring board preparation step of preparing a ceramic wiring board provided with the through conductor portion;
An elevation difference providing step of providing the elevation difference on the main surface of the ceramic wiring board;
And a laminating step in which the wiring structure is pressure-bonded to the substrate main surface by performing heat and pressure in a state where the wiring structure is disposed on the substrate main surface having the height difference. A method for manufacturing a multilayer wiring board. In the laminating step, the wiring structures are collectively applied to the substrate main surface by performing heat and pressure in a state where a plurality of the wiring structures are arranged on the substrate main surface where the height difference exists. The method for manufacturing a multilayer wiring board according to claim 5 , wherein the bonding is performed. In the height difference application step, in the substrate main surface of the ceramic wiring substrate after the firing step, by removing the ceramic material of the substrate peripheral portion, claim 5 or 6, characterized in that providing the height difference The manufacturing method of the multilayer wiring board as described in any one of. In the height difference providing step, the substrate main surface of the ceramic wiring substrate that has undergone the firing step is surface-polished in advance, and then the ceramic material on the outer peripheral portion of the substrate is removed on the surface-polished substrate main surface. the method of manufacturing a multilayer wiring board according to claim 5 or 6, characterized in that providing the height difference.

Images