JP2016009810A - Wiring board manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring board manufacturing method which can improve yield by enabling accurate formation of a through hole even when an inner diameter of the through hole is small.SOLUTION: A wiring board of the present embodiment is manufactured through a base material preparation process, a base material placement process and a through hole formation process. In the base material preparation process, a base material 45 having a first surface 46 and a second surface 47 is prepared. In the base material placement process, the base material 45 is placed on a support surface 50 of a support member 49 in a state where the first surface 46 faces the support surface 50 and a light-permeable protection layer 51 is sandwiched between the base material 45 and the support member 49. In the through hole formation process, through holes 26 each of which pierces the base material 45 in a thickness direction by irradiation of laser beams L1. Note that, a hole 53 is provided in the support member 49. An inner diameter A2 of the hole 53 is set at equal to or larger than an inner diameter A1 of each through hole 26 and less than a pitch A3 between adjacent through holes 26.

Description

  The present invention relates to a method for manufacturing a wiring board in which a plurality of through holes are formed in a base material such as a resin insulating layer.

  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 the IC chip. Therefore, in order to inspect this IC chip, a dedicated inspection device, for example, an inspection device provided with a wiring board for electronic component inspection is required.

  As an electronic component inspection wiring board, for example, a plurality of resin insulating layers and a plurality of wiring layers are laminated on the upper layer side of a ceramic substrate portion formed by laminating a plurality of ceramic insulating layers and a plurality of conductor layers. A wiring board on which a resin insulating portion is formed has been put into practical use. A plurality of through holes are formed in a base material such as a ceramic insulating layer or a resin insulating layer, and a through conductor (via conductor) is formed in each through hole. In addition, a through-hole is formed by irradiating a laser with respect to a base material (for example, refer patent document 1).

  Hereinafter, a method for forming a through hole in the resin insulating layer (base material) will be described. First, a base material 103 made of a resin material is prepared (see FIG. 12). Note that a metal layer 101 serving as a wiring layer is formed on the surface 102 of the base material 103. Next, the base material 103 is placed on the support surface 105 in a state where the back surface 106 faces the support surface 105 of the lower jig 104 made of acrylic resin, and the paper 107 made of flame-retardant fiber is used as a base. It is interposed between the material 103 and the lower jig 104 (see FIG. 12). A plurality of through holes 108 are formed in the base material 103 by irradiating the base material 103 with a laser (generally a carbon dioxide laser) (see FIG. 12).

JP 2007-175721 A (FIGS. 2 to 4 etc.)

  Incidentally, in recent years, in response to the trend toward miniaturization of IC chips, the inner diameter of the through hole 108 on the electronic component inspection wiring board side also tends to be reduced. However, since the output of the carbon dioxide laser is too strong, if the inner diameter of the through-hole 108 is 60 μm or less, for example, the base material 103 or the metal layer 101 is melted under the influence of the processing heat of the laser. As a result, there is a variation in the inner diameter of the through-hole 108 to be formed, and the through-hole 108 cannot be formed accurately, resulting in a problem that the defective product generation rate increases and the yield decreases.

  In addition, it has also been proposed to form the through-hole 108 using a relatively low-power UV laser instead of using a carbon dioxide laser. However, when the inner diameter of the through hole 108 is 50 μm or less, even if it is a UV laser, the base material 103 or the metal layer 101 is melted by the influence of the laser processing heat, and the inner diameter of the through hole 108 is reduced. Variations may occur. Therefore, also in this case, since the through-hole 108 cannot be formed accurately, there is a problem that the defective product generation rate is increased and the yield is lowered.

  The present invention has been made in view of the above problems, and the object thereof is to improve the yield by enabling the through-hole to be accurately formed even when the through-hole has a small inner diameter. The object is to provide a method of manufacturing a wiring board.

  As means (means 1) for solving the above-mentioned problems, the base material is thickened on a base material formed in a plate shape having a first surface and a second surface located on the opposite side of the first surface. A method of manufacturing a wiring board in which a plurality of through holes penetrating in a vertical direction is formed, the base material preparing step for preparing the base material, and the first surface facing a support surface of a support member made of a metal material In this state, the base material is placed on the support surface, and a base material placement step of interposing a protective layer made of a light-transmitting material between the base material and the support member; The support used in the substrate placing step, including a through hole forming step of forming the plurality of through holes in the substrate by irradiating a laser from the side opposite to the support member side in the substrate In the member, a plurality of holes at positions corresponding to the plurality of through holes to be formed There is provided a method of manufacturing a wiring board, wherein the size of the inner diameter of the hole is equal to or larger than the inner diameter of the through hole and less than the pitch between the adjacent through holes. .

  Therefore, in the invention described in the means 1, the base material is placed on the support surface of the support member provided with the plurality of holes in the base material placing step. As a result, even if the substrate is irradiated with a laser in the through hole forming step, the laser processing heat applied to the substrate is diffused through the support member made of the metal material and passes through the hole to the outside. Released. In addition, in the substrate placing step, a protective layer made of a light transmissive material is interposed between the substrate and the support member. As a result, the laser irradiated to the base material travels straight through the protective layer, so that it is difficult for the laser to scatter within the base material. From the above, even when the inner diameter of the through hole is small, variations in the inner diameter of the through hole due to laser processing heat and laser scattering are less likely to occur, and the through hole can be formed accurately. Therefore, the defective product occurrence rate is kept low, and the yield of manufactured wiring boards is increased.

  Hereinafter, a method of manufacturing the wiring board according to the means 1 will be described.

  In the base material preparation step, a base material formed in a plate shape having a first surface and a second surface located on the opposite side of the first surface is prepared. Although it does not specifically limit as a kind of base material and is arbitrary, For example, it is suitable for it to be the resin insulating material used as a resin insulating layer. When the base material is a resin insulating material, a problem peculiar to the present application that the base material is melted by the processing heat of the laser tends to occur. In addition, as another base material, the insulating layer which consists of various ceramics, for example can also be selected.

  The resin insulating material can be appropriately selected in consideration of insulation, heat resistance, moisture resistance, and the like. Preferable examples of the polymer material for forming the resin insulating material include epoxy resin, polyimide resin, phenol resin, urethane resin, silicone resin, bismaleimide-triazine resin, and polyphenylene ether resin.

  In the base material preparation step, it is preferable to prepare a base material in which a metal layer to be a wiring layer is formed on at least one of the first surface and the second surface. In this way, since an electric circuit composed of a wiring layer can be formed on the wiring board, the functionality of the wiring board can be enhanced. Furthermore, the metal layer is preferably a copper foil. In this case, since a film with copper foil, which is a general-purpose material that is generally used, can be used, the manufacturing cost of the wiring board can be kept low.

  In the subsequent substrate placing step, the substrate is placed on the support surface with the first surface of the substrate facing the support surface of the support member made of a metal material. The support member used here has a structure in which a plurality of holes are provided at positions corresponding to the plurality of through holes to be formed in the base material. Examples of the metal material constituting the support member include stainless steel (SUS303, SUS304, etc.), copper, aluminum, nickel, and the like.

  In the substrate placing step, a protective layer made of a light transmissive material is interposed between the substrate and the support member. The material for forming the protective layer is appropriately selected in consideration of light transmittance, heat resistance, pressure resistance, releasability, etc., as well as low damage to the base material and support member, and low cost. The Therefore, for example, a resin material or glass is preferably used as the protective layer. Here, examples of the resin material used for the protective layer include polyethylene terephthalate resin, polycarbonate resin, and acrylic resin. In particular, the protective layer is preferably formed of a polyethylene terephthalate resin that is relatively excellent in releasability among resin materials.

  In addition, the protective layer may be formed on the 1st surface of a base material, and may be formed on the support surface of a support member. The protective layer is preferably formed on both the first surface and the second surface. In this case, after the laser goes straight through the inside of the protective layer formed on the second surface (that is, the protective layer formed on the side opposite to the support member side in the base material), Since the inside of the protective layer (that is, the protective layer formed on the support member side in the substrate) goes straight, the laser becomes more difficult to scatter in the substrate. As a result, variations in the inner diameter of the through-hole due to laser scattering are more unlikely to occur, and the through-hole can be formed more accurately. Yield is even higher.

  In the subsequent through-hole forming step, a plurality of through-holes are formed in the base material by irradiating the base material with laser from the side opposite to the support member side. Here, a well-known technique can be adopted as the laser, and specific examples include a UV laser, a carbon dioxide gas laser, and a YAG laser. Conventionally, a carbon dioxide laser is the mainstream, but when a through hole having an inner diameter of, for example, 40 μm or less is formed, the output is too strong, making it difficult to form the through hole. Therefore, the laser is, for example, a UV laser, and in the through-hole forming step, it is preferable to form the through-hole by irradiating the laser several times along a virtual circle serving as an opening edge of the through-hole. Since the UV laser has a relatively low output, when the laser is irradiated in a plurality of times, the through-hole can be reliably formed while avoiding damage to the base material due to the processing heat of the laser.

  The inner diameter of the through holes is preferably set to 40 μm or less, and the pitch between adjacent through holes is preferably set to 100 μm or less. In such a case, it is possible to make the wiring finer and higher in density in the manufactured wiring board. Further, the above means 1 is more likely to cause a problem peculiar to the present application that the base material is melted by the processing heat of the laser and a problem peculiar to the present application that adjacent through holes are connected in the case of a fine pitch of 100 μm or less. Significance of adopting will increase.

  Moreover, it is good to perform the through-conductor formation process which fills a conductive paste in a through-hole, and forms a through-conductor after a through-hole formation process. In this way, when forming an insulating portion formed by laminating a plurality of base materials and a plurality of metal layers (wiring layers), the metal layers formed on the base materials are surely formed through the through conductors. Can be connected.

  A wiring board is manufactured through the above processes. The structure of the wiring board is not particularly limited, and examples thereof include a build-up multilayer wiring board having a build-up layer on one side or both sides of the core board, and a coreless wiring board having no core board. The wiring board is provided with a resin insulating portion in which a plurality of resin insulating layers made of a base material and a plurality of wiring layers are laminated, a lower layer side of the resin insulating portion, and a plurality of ceramic insulating layers and a plurality of conductor layers May be a wiring board for inspection of electronic components.

Sectional drawing which shows schematic structure of the wiring board for electronic component inspection in this embodiment. The expanded sectional view which shows the connection part of a wiring layer and a penetration conductor. Explanatory drawing which shows the process of forming the through-hole of a ceramic substrate part. Explanatory drawing which shows the process of forming the via conductor and conductor layer of a ceramic substrate part. Explanatory drawing which shows the process of forming the ceramic laminated body used as a ceramic substrate part. Explanatory drawing which shows a base material preparation process. Explanatory drawing which shows a base material mounting process. Explanatory drawing which shows a through-hole formation process. The principal part top view which shows a through-hole formation process. Explanatory drawing which shows a penetration conductor formation process. Explanatory drawing which shows the process of forming a wiring layer. Explanatory drawing which shows the manufacturing method of the wiring board in a prior art.

  Hereinafter, an embodiment in which the present invention is embodied in an electronic component inspection wiring board will be described in detail with reference to the drawings.

  As shown in FIG. 1, an electronic component inspection wiring board 10 (hereinafter referred to as “wiring board 10”) according to the present embodiment is used as a part of an inspection apparatus for performing an electrical inspection of an IC chip (electronic component). Parts to be used. The wiring substrate 10 includes a resin insulating part 20 and a ceramic substrate part 30 provided on the lower layer side of the resin insulating part 20. The wiring board 10 is a wiring board having a vertical and horizontal length of about 10 cm and a thickness of about 4 mm. In use, the main surface 11 (the surface of the resin insulating portion 20) of the wiring board 10 is an IC chip to be inspected. Placed.

  The ceramic substrate portion 30 has a structure in which ceramic insulating layers 31, 32, 33 and conductor layers 34 are alternately stacked. Each of the ceramic insulating layers 31 to 33 is, for example, an alumina sintered body, and the conductor layer 34 is a metallized layer made of, for example, tungsten, molybdenum, or an alloy thereof. A through hole 36 penetrating in the thickness direction is formed in each ceramic insulating layer 31 to 33, and a through conductor 37 connected to the conductor layer 34 is formed in the through hole 36. Each through-hole 36 has a circular cross section, and the inner diameter is set to about 60 μm. Each through conductor 37 has a circular cross-section and an outer diameter of about 60 μm. The through conductor 37 is a metallized layer made of the same material as the conductor layer 34, that is, tungsten, molybdenum, or an alloy thereof. Furthermore, on the back surface 12 of the wiring substrate 10 (the back surface of the ceramic substrate portion 30), a plurality of back surface side terminals 38 are formed in an array over almost the entire area. Each back-side terminal 38 has a circular cross section and a diameter of about 1.0 mm.

  As shown in FIG. 1, the resin insulating portion 20 has a structure in which resin insulating layers 21 and 22 and wiring layers 23 are alternately stacked. Each of the resin insulating layers 21 and 22 is an insulating layer made of, for example, a polyimide resin. Specifically, the resin insulating layers 21 and 22 are formed on both surfaces of the first resin layer 24 made of a polyimide-based thermosetting resin and the first resin layer 24, and are made of a polyimide-based thermoplastic resin. 2 resin layers 25. In the present embodiment, the thickness of the first resin layer 24 is set to about 20 μm, and the thickness of the second resin layer 25 is set to about 5 μm. Therefore, the thickness of the resin insulating layers 21 and 22 is about 30 μm. The wiring layer 23 is a conductor layer made of copper, for example, and has a thickness of about 5 μm.

  As shown in FIGS. 1 and 2, each resin insulation layer 21, 22 is formed with a through hole 26 that penetrates the resin insulation layers 21, 22 and the wiring layer 23 in the thickness direction. A through conductor 27 connected to the wiring layer 23 is formed. Each through hole 26 has a circular cross section, and an inner diameter A1 is set to 30 μm. A pitch A3 (see FIG. 8) between the adjacent through holes 26 is set to 60 μm. Each through conductor 27 has a circular cross section and an outer diameter of 30 μm. The through conductor 27 is made of copper, which is a material different from that of the wiring layer 23.

  Furthermore, a plurality of main surface side terminals 28 which are the wiring layers 23 are formed in an array at the central portion on the main surface 11 (the surface of the resin insulating portion 20) of the wiring substrate 10. Each main surface side terminal 28 has a circular cross section and has a diameter of, for example, about 50 μm. Therefore, in the wiring board 10 shown in FIG. 1, each main surface side terminal 28 is connected to the wiring layer 23 on the inner layer side through the through conductor 27, and further the conductor layer 34 and the through conductor 37 of the ceramic substrate portion 30 are connected. To the back side terminal 38.

  Next, a method for manufacturing the wiring board 10 will be described.

  First, a plurality of green sheets 41 are formed using a ceramic material mainly composed of alumina powder (see FIG. 3). Then, a plurality of through holes 36 are formed at predetermined positions by drilling the plurality of green sheets 41 by laser processing, punching processing, drilling, or the like (see FIG. 3). Thereafter, using a conventionally known paste printing apparatus (not shown), each through hole 36 is filled with a conductive paste (for example, tungsten paste) to form an unfired through conductor 37 (see FIG. 4). Further, using a paste printing device, a conductive paste is printed on the front and back surfaces of each green sheet 41 to form unfired conductor layers 34 and unfired backside terminals 38 (see FIG. 4). The order of filling and printing with the conductive paste may be reversed.

  Then, after the conductive paste is dried, the green sheets 41 are stacked and a pressing force is applied in the sheet stacking direction. As a result, the green sheets 41 are integrated to form a ceramic laminate 43 (see FIG. 5). Next, the ceramic laminate 43 is degreased and fired at a predetermined temperature for a predetermined time. As a result, the alumina of the green sheet 41 and the tungsten in the paste are simultaneously sintered, and the ceramic substrate portion 30 is formed.

  Moreover, the resin insulation layers 21 and 22 which comprise the resin insulation part 20 are produced with the following method. Specifically, first, a base material preparation step is performed to prepare a resin insulating material 45 (base material) to be the resin insulating layers 21 and 22 (see FIG. 6). The resin insulating material 45 is formed in a plate shape having a first surface 46 and a second surface 47 located on the opposite side of the first surface 46, and a copper foil 48 (metal) having a thickness of 5 μm serving as the wiring layer 23. Layer) is a resin film with a copper foil affixed to the second surface 47 (the upper surface in FIG. 6). The resin insulating material 45 includes the first resin layer 24 and the second resin layer 25 disposed on both surfaces of the first resin layer 24.

  In the subsequent substrate mounting step, first, a protective film 51 (protective layer) having a thickness of 50 μm or less is pasted on the first surface 46 of the resin insulating material 45 using a conventionally known laminator (see FIG. 7). Similarly, a protective film 52 (protective layer) having a thickness of 50 μm or less is also pasted on the second surface 47 of the resin insulating material 45 (specifically, on the surface of the copper foil 48). As a result, the protective films 51 and 52 having a common thickness are formed on both the first surface 46 and the second surface 47. In addition, the protective films 51 and 52 of this embodiment are formed in the sheet form with the polyethylene terephthalate resin which is a material which has a light transmittance. That is, the protective films 51 and 52 are made of a common material.

  Then, the resin insulating material 45 in which the through hole 26 (see FIG. 8) is to be formed is supported on the support surface 50 with the first surface 46 of the resin insulating material 45 facing the support surface 50 of the support jig 49 (support member). Place it on top (see Figure 7). At this time, the protective film 51 is interposed between the resin insulating material 45 and the support jig 49. The support jig 49 used in the substrate placing step is formed in a plate shape from stainless steel (SUS303), which is a metal material, and has a thickness of 80 μm. In the support jig 49, a plurality of holes 53 that penetrate the support jig 49 in the thickness direction are provided at positions corresponding to the plurality of through holes 26 to be formed. The size of the inner diameter A2 of the hole 53 is not less than the inner diameter A1 (30 μm) of the through hole 26 and less than the pitch A3 (60 μm) between the adjacent through holes 26, and is set to 35 μm in this embodiment. (See FIGS. 7 and 8).

  In the subsequent through-hole forming step, the resin insulating material 45 is irradiated with a laser L1 (in this embodiment, a UV laser) from the side opposite to the support jig 49 side (specifically, the second surface 47 side), thereby forming the resin. A plurality of through holes 26 penetrating the insulating material 45 in the thickness direction are formed (see FIG. 8). Specifically, the laser L1 is moved while moving the laser irradiation device (not shown) along the virtual circle C1 (see FIG. 9) serving as the opening edge of the through hole 26 in the plane direction (clockwise direction in the present embodiment). Irradiate in several steps. As a result, one through hole 26 is formed. All the through holes 26 are formed by performing similar laser irradiation on the remaining through holes 26. Thereafter, the protective films 51 and 52 are peeled off.

  Then, in the through conductor forming step after the through hole forming step, a conductive paste (specifically, in the through hole 26 from the second surface 47 side of the resin insulating material 45 using a paste printing device (not shown). Fill with silver paste. And the penetration conductor 27 is formed by heating at the temperature of about 180 degreeC for 1 hour (refer FIG. 10).

  Thereafter, a wiring layer forming step is performed, and the copper foil 48 of the resin insulating material 45 is patterned by a subtractive method to form the main surface side terminal 28 (wiring layer 23) on the resin insulating layer 21 (see FIG. 11). Specifically, a dry film is laminated on each of the first surface 46 and the second surface 47 of the resin insulating material 45, and the dry film is exposed and developed. As a result, an etching resist is formed so as to cover the entire first surface 46 of the resin insulating layer 21, and an etching resist having a predetermined pattern is formed on the second surface 47 of the resin insulating layer 21. In this state, the main surface side terminal 28 is formed on the resin insulating layer 21 by performing patterning by etching on the copper foil 48. Thereafter, the contact with the stripping solution removes the etching resist remaining on the main surface side terminal 28 and the etching resist on the first surface 46 side.

  Through the above steps, the resin insulating layer 21 having the main surface side terminals 28 and the through conductors 27 connected to the main surface side terminals 28 is formed. Moreover, the resin insulation layer 22 which has the wiring layer 23 and the penetration conductor 27 connected to the wiring layer 23 is formed by performing the base material preparation process-wiring layer formation process mentioned above similarly.

Next, the resin insulating layer 21 and the resin insulating layer 22 are stacked on the upper layer side of the ceramic substrate portion 30 and pressurized at a pressure of about 30 to 100 kgf / cm ² while being heated to a temperature of about 300 to 400 ° C. . As a result, the wiring substrate 10 in which the resin insulating portion 20 and the ceramic substrate portion 30 are integrated is manufactured (see FIG. 1). In the above manufacturing process, after the resin insulating layer 21 and the resin insulating layer 22 are pressure laminated, the wiring substrate 10 laminated on the ceramic substrate unit 30 may be produced.

  Next, the evaluation method of the resin insulating material 45 and the result will be described.

  First, a measurement sample was prepared as follows. The same resin insulating material 45 as that of the present embodiment, specifically, a copper foil 48 is formed on the second surface 47, and the protective films 51 and 52 are pasted on both the first surface 46 and the second surface 47. The prepared resin insulating material 45 was prepared and used as an example. Moreover, although the copper foil was formed, the resin insulating material in which the protective films 51 and 52 were not affixed was prepared and this was made into the comparative example.

Next, a plurality of through holes were formed in each measurement sample by irradiating a laser from the copper foil side of each measurement sample (Example, Comparative Example). And the internal diameter of the through-hole in the X direction (refer FIG. 9) and the Y direction (refer FIG. 9) was measured in the incident surface (surface on the copper foil side) of the laser of each measurement sample. Further, the average value, maximum value, and minimum value of all the inner diameters on the incident surface were calculated, and the standard deviation of the inner diameter on the incident surface was calculated. In addition, on the laser emission surface (surface on the resin insulation side) of each measurement sample, the inner diameters of the through holes in the X direction and the Y direction are measured, and the average value, maximum value, and minimum value of all inner diameters on the emission surface are measured. And the standard deviation of the inner diameter at the exit surface was calculated. Then, for each measurement sample, a taper ratio derived from the equation {(average value of inner diameters on the exit surface) / (average value of inner diameters on the incident surface)} × 100 was calculated. The results are shown in Table 1. In addition, nine samples for each measurement were prepared.

  As a result, in the comparative example, the average value of the inner diameter on the incident surface was 37.7 μm, the maximum value was 40 μm, the minimum value was 35 μm, and the standard deviation of the inner diameter on the incident surface was 1.7. In the comparative example, the average value of the inner diameter on the exit surface was 30.9 μm, the maximum value was 32 μm, the minimum value was 30 μm, and the standard deviation of the inner diameter on the exit surface was 0.7. Furthermore, in the comparative example, the taper rate was 81.80%.

  On the other hand, in the example, the average value of the inner diameter at the incident surface was 27.9 μm, the maximum value was 31 μm, the minimum value was 26 μm, and the standard deviation of the inner diameter at the incident surface was 1.5. In the example, the average value of the inner diameter on the exit surface was 27.4 μm, the maximum value was 30 μm, the minimum value was 26 μm, and the standard deviation of the inner diameter on the exit surface was 1.2. Furthermore, in the Example, the taper rate became 98.20%.

  From the above, if the through hole is formed with the protective film pasted on both surfaces (first surface and second surface) of the resin insulating material, the inner diameter on the incident surface does not become too large, and the through hole is less likely to be tapered. It was confirmed that can be formed.

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

  (1) In the manufacturing method of the wiring board 10 of the present embodiment, the resin insulating material 45 is placed on the support surface 50 of the support jig 49 provided with the plurality of holes 53 in the base material placing step. Yes. As a result, even if the resin insulating material 45 is irradiated with the laser L1 in the through-hole forming step, the processing heat of the laser L1 applied to the resin insulating material 45 causes the support jig 49 made of a metal material (stainless steel in this embodiment) to And is released to the outside through the hole 53. In addition, in the substrate placing step, a protective film 51 made of a light transmissive material (polyethylene terephthalate resin in the present embodiment) is interposed between the resin insulating material 45 and the support jig 49. As a result, since the laser L1 irradiated to the resin insulating material 45 travels straight in the protective film 51, the laser L1 is less likely to be scattered in the resin insulating material 45. From the above, even when the inner diameter A1 of the through hole 26 is small, variations in the inner diameter A1 of the through hole 26 due to the processing heat of the laser L1 and the scattering of the laser L1 are less likely to occur, and the through hole 26 can be accurately Can be formed. Therefore, the defective product occurrence rate is suppressed low, and the yield of the manufactured wiring board 10 is increased.

  (2) In the conventional manufacturing method, the through-hole 108 is formed in the base material 103 by laser irradiation, but the base material 103 or the metal layer 101 may be melted under the influence of laser processing heat ( (See FIG. 12). In particular, since excessive processing heat is applied to the laser incident surface (the upper surface in FIG. 12), the inner diameter of the through hole 108 on the incident surface is likely to increase, and the end of the through hole 108 on the incident surface side is likely to rise. Become. In this case, a large taper is generated in the formed through hole 108 (that is, the taper rate is small), and thus there is a problem that the through hole 108 cannot be formed accurately.

  Therefore, in the present embodiment, not only the protective film 51 is formed on the first surface 46 of the resin insulating material 45 but also the protective film 52 is stuck on the second surface 47 of the resin insulating material 45, and the penetration is made. A hole 26 is formed. In this case, the laser L1 travels straight inside the protective film 52 and then enters the resin insulating material 45 from the second surface 47 side in the same direction. Therefore, the laser L1 is near the second surface 47 of the resin insulating material 45. Becomes difficult to scatter. As a result, it is difficult for excessive processing heat to be applied to the second surface 47, which is the laser incident surface, so that the inner diameter of the through hole 108 on the incident surface is increased and the end of the through hole 108 on the incident surface side is raised. It will be suppressed. Therefore, the taper generated in the through-hole 26 is reduced, and a plurality of through-holes 26 can be formed at a fine pitch. Therefore, the defective product generation rate is further suppressed, and the yield of the manufactured wiring board 10 is further increased. Become.

  (3) The through-hole 26 of the present embodiment is formed by irradiating the laser L1 in a plurality of times along a virtual circle C1 (see FIG. 9) serving as an opening edge of the through-hole 26. As described above, when the laser L1 is irradiated in a plurality of times, the cumulative amount of heat applied to the processed portion of the resin insulating material 45 is reduced. Can be formed.

  (4) In the wiring substrate 10 of the present embodiment, the resin insulating layers 21 and 22 are formed on both surfaces of the first resin layer 24 made of a polyimide-based thermosetting resin and the first resin layer 24, and polyimide-based The second resin layer 25 is made of a thermoplastic resin. In this case, since the second resin layer 25 functions as an adhesive layer by heating and pressing in the step of laminating the resin insulation layers 21 and 22, the resin in which the resin insulation layers 21 and 22 are integrated. The wiring board 10 having the insulating part 20 can be reliably manufactured.

  In addition, you may change this embodiment as follows.

  In the substrate placing process of the above embodiment, the resin insulating material 45 having the sheet-like protective film 51 attached on the first surface 46 is placed on the support surface 50 of the support jig 49. However, in the substrate placing step, the resin insulating material 45 may be placed on the sheet-like protective film 51 attached to the support surface 50 of the support jig 49.

  In the above embodiment, the resin insulating material 45 in which the protective film 51 is stuck on the first surface 46 and the protective film 52 is stuck on the second surface 47 is used. However, a resin insulating material in which a protective film is attached only on the first surface 46 may be used. That is, the protective film stuck on the second surface 47 may be omitted.

  -In the said embodiment, the resin insulating material 45 in which the copper foil 48 was formed only in the 2nd surface 47 was used as a base material prepared in a base material preparation process. However, a resin insulating material in which the copper foil 48 is formed only on the first surface 46 may be used, or a resin insulating material 45 in which the copper foil 48 is formed on both the first surface 46 and the second surface 47 is used. May be.

  -In the said embodiment, the silver paste was used as an electrically conductive paste with which the through-hole 26 is filled in a through-conductor formation process. However, the present invention is not limited to this, and other conductive pastes such as a copper paste or a paste containing silver and copper may be used.

  -In the said embodiment, although the sintered compact of the alumina was used as the ceramic insulating layers 31-33, it is not necessarily limited to this. For example, glass ceramic may be used instead of alumina. When glass ceramic is used, as the via conductor 34 and the through conductor 37, silver, copper, or an alloy thereof is used.

  In the above embodiment, the present invention is embodied in the electronic component inspection wiring substrate 10 including the resin insulating portion 20 and the ceramic substrate portion 30. However, the present invention is embodied in a wiring substrate used in other applications. Also good. For example, the present invention may be embodied in a multilayer wiring board composed of a plurality of resin insulating layers.

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

  (1) In the means 1, the protective layer is formed on both the first surface and the second surface, the protective layer formed on the first surface, and the second surface A method for manufacturing a wiring board, wherein the protective layer formed thereon is made of a common material.

  (2) In the above means 1, the protective layer is formed on both the first surface and the second surface, the protective layer formed on the first surface, and the second surface A method for manufacturing a wiring board, wherein the protective layer formed thereon has a common thickness.

  (3) In the above means 1, in the base material placing step, the base material having the sheet-like protective layer stuck on the first surface is placed on the support surface. A method for manufacturing a substrate.

  (4) In the said means 1, the said base material mounting process WHEREIN: The said base material is mounted on the said sheet-like protective layer affixed on the said supporting member, The manufacturing method of the wiring board characterized by the above-mentioned.

  (5) In the said means 1, the said protective layer is a protective film 50 micrometers or less in thickness, The manufacturing method of the wiring board characterized by the above-mentioned.

  (6) In the above means 1, the support member is a plate-like jig in which the base material on which the through hole is to be formed is placed on the support surface, and the plurality of holes penetrates in the thickness direction. A method for manufacturing a wiring board, wherein:

  (7) In the above means 1, the wiring board is provided on a lower side of the resin insulation part, a resin insulation part in which a plurality of resin insulation layers made of the base material and a plurality of wiring layers are laminated, A method of manufacturing a wiring board, comprising: an electronic component inspection wiring board comprising: a ceramic substrate layer on which a ceramic insulating layer and a plurality of conductor layers are laminated.

10. Wiring board (wiring board for electronic component inspection)
21, 22 ... Resin insulating layer 23 ... Wiring layer 26 ... Through hole 27 ... Through conductor 45 ... Resin insulating material 46 as base material ... First surface 47 ... Second surface 48 ... Copper foil 49 as metal layer ... Support member Supporting jig 50 as a support surface 51, 52 ... Protective film 53 as a protective layer ... Hole A1 ... Inside diameter A2 of the through hole ... Pitch C1 between the through holes C1 ... Virtual circle L1 ... Laser

Claims (8)

A wiring board in which a plurality of through holes penetrating the base material in the thickness direction are formed in a base material formed in a plate shape having a first surface and a second surface located on the opposite side of the first surface A manufacturing method of
A substrate preparation step of preparing the substrate;
With the first surface facing the support surface of a support member made of a metal material, the base material is placed on the support surface, and a protective layer made of a light-transmitting material is disposed on the base material and the base material. A substrate placing step to be interposed between the support member,
A through hole forming step of forming the plurality of through holes in the base material by irradiating a laser from the side opposite to the support member side in the base material;
In the support member used in the substrate placing step, a plurality of holes are provided at positions corresponding to the plurality of through holes to be formed,
The method of manufacturing a wiring board, wherein the size of the inner diameter of the hole is equal to or larger than the inner diameter of the through hole and less than the pitch between the adjacent through holes.   The method for manufacturing a wiring board according to claim 1, wherein the protective layer is formed on both the first surface and the second surface.   The wiring according to claim 1 or 2, wherein in the base material preparation step, the base material in which a metal layer to be a wiring layer is formed on at least one of the first surface and the second surface is prepared. A method for manufacturing a substrate.   The method for manufacturing a wiring board according to claim 3, wherein the metal layer is a copper foil. The laser is a UV laser;
The said through-hole formation process forms the said through-hole by irradiating a laser in multiple times along the virtual circle used as the opening edge of the said through-hole in the said through-hole formation process. A method for manufacturing a wiring board according to claim 1.   6. The wiring board manufacturing method according to claim 1, wherein an inner diameter of the through hole is set to 40 μm or less, and a pitch between the adjacent through holes is set to 100 μm or less. Method.   The wiring board according to claim 1, wherein after the through hole forming step, a through conductor forming step of forming a through conductor by filling the through hole with a conductive paste is performed. Manufacturing method.   The method for manufacturing a wiring board according to claim 1, wherein the base material is a resin insulating material to be a resin insulating layer.

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