JP4467125B2 - Manufacturing method of multilayer printed wiring board - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention provides a multilayer printed wiring board in which an interlayer resin insulation layer and a conductor layer are alternately laminated, and a buildup layer in which each conductor layer is connected by a via hole is formed on both surfaces of a core substrate. Manufacturing methodLawIt is about.
[0002]
[Prior art]
Conventionally, a build-up multilayer printed wiring board is manufactured by, for example, a method disclosed in JP-A-9-130050.
For the core substrate of the multilayer printed wiring board, a copper clad laminate having copper foil laminated on both sides is used. First, the copper-clad laminate was drilled, electroless-plated, and etched into a pattern to form inner layer copper patterns and through holes on both sides of the substrate.
[0003]
Thereafter, an interlayer insulating resin is applied by a roll coater or printing. Then, a mask is brought into close contact with the interlayer insulating resin, exposed and developed to form a via hole opening for interlayer conduction. Thereafter, an interlayer resin insulation layer is formed through UV curing and main curing. Further, the interlayer resin insulation layer is subjected to a roughening treatment with an acid or an oxidizing agent, and a catalyst such as palladium is attached to the roughened surface. Then, a thin electroless plating film is formed, and a pattern is formed on the plating film with a dry film. Further, after thickening by electrolytic plating, the dry film is peeled off with alkali and etched to produce a conductor circuit. Next, an upper interlayer resin insulation layer is formed and the above steps are repeated. Thereby, a build-up multilayer printed wiring board is obtained.
[0004]
In addition, a solder resist layer is applied to the outermost layer of the printed wiring board in order to protect the conductor circuit. When forming solder bumps, solder bumps are printed by opening a part of the solder resist layer for connection to the conductor circuit, printing the solder paste on the exposed conductor circuit, and performing reflow. Is forming.
Here, as a method for opening the solder resist layer, first, a photosensitive resin is used as the solder resist. Next, a mask with a black circle is placed on the solder resist at a position corresponding to the opening. Then, the solder resist is exposed to dissolve the unexposed portion corresponding to the black circle position of the mask. Thereby, an opening was formed in the solder resist layer.
[0005]
[Problems to be solved by the invention]
However, in the above-described method of forming a through hole by a drill and forming a via hole and an opening of a solder resist layer by an exposure phenomenon, it is not possible to form fine openings and through holes at a narrow pitch, and a multilayer printed wiring board In some cases, it may not be possible to satisfy the performance required for high integration.
[0006]
For this reason, this inventor devised forming an opening and a through-hole using a laser (a carbon dioxide gas, excimer, UV, YAG) on a printed wiring board. However, even if a laser is used, it is difficult to form small-diameter openings and through-holes at accurate positions. Further, if the laser is irradiated to form fine openings and through-holes one by one, the processing time is reduced. Was expected to be longer.
[0007]
  The present invention has been made to solve the above-described problems, and an object of the present invention is to produce a multilayer printed wiring board in which the wiring density is increased and the opening and the through hole are formed at an accurate position.LawIs to provide.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the invention of claim 1 lies in a method for manufacturing a multilayer printed wiring board characterized by including at least the following steps (A) to (C):
(A) a step of aligning the substrate and the mask from a positioning mark provided on the substrate and a positioning mark provided on a mask having an opening;
(B) a step of adsorbing the mask to the substrate side through a through hole formed in the substrate;
(C) A step of irradiating the mask with a laser to form a plurality of through holes in the substrate.
[0009]
According to a first aspect of the present invention, the substrate and the mask are aligned by positioning marks provided on both the substrate and the mask. Thereafter, air is sucked out through the through-hole formed in the substrate, thereby reducing the pressure between the mask and the substrate or bringing the mask into close contact with the substrate. This prevents the mask from being displaced from the substrate. Therefore, when the opening is formed in the substrate with the laser through the mask, the opening can be accurately formed at the opening forming position of the substrate.
[0010]
In addition, since a plurality of fine through holes are formed in the mask at a narrow pitch, a plurality of fine holes are collectively applied to the substrate by irradiating the substrate with a laser through the mask. Openings can be formed at a narrow pitch. Furthermore, since the through-hole is formed in the substrate by a laser, the material for the interlayer resin insulating layer and the solder resist layer is not limited to the photosensitive resin, unlike the case of forming the through-hole by exposure and development processing. Materials can be used.
[0011]
  The invention of claim 2 is a method for producing a multilayer printed wiring board characterized by comprising at least the following steps (A) to (C):
(A) A step of aligning the substrate and the mask from a positioning mark provided on a substrate for multi-cavity and a positioning mark provided on a mask having an opening.Because
A step of adsorbing the mask to the substrate side through a through hole formed in the substrate;When,
(B) irradiating the mask with a laser to form a plurality of through holes in the substrate;
(C) A step of moving the mask, moving the multi-piece substrate, and performing the steps (A) and (B).
[0012]
According to a second aspect of the present invention, the multiple substrate and the mask are aligned by positioning marks provided on both the multiple substrate and the mask. For this reason, it is possible to accurately form openings in the multi-piece substrate with a laser through the mask. In addition, since a plurality of through holes are formed in the mask, a plurality of fine openings can be formed in a plurality of substrates at once.
[0013]
Since the mask is a size of a plurality of substrate units of the multi-piece substrate, the area is smaller than the mask corresponding to the multi-piece substrate, and the influence of expansion and contraction of the mask due to the heat of the laser is small. Therefore, the accuracy of forming the opening in the substrate can be improved. In addition, since the mask is moved and moved on the substrate for picking up multiple pieces and the above process is repeated, the mask can be reused. In addition, it is also possible to process in a lump by forming a mask with the same size as the substrate for taking a large number of pieces.
[0015]
  Claim2Then, by sucking out air through the through holes formed in the multi-piece substrate, the pressure between the mask and the multi-piece substrate is reduced or reduced to a vacuum state, and the mask is Adhere closely to the substrate side for picking up multiple pieces. For this reason, the mask does not deviate from the multiple substrate. Therefore, when an opening is formed in the multi-piece substrate with the laser through the mask, the opening can be accurately formed at the opening forming position of the multi-piece substrate. The through holes are preferably formed at the four corners of the substrate. In particular, it is desirable to form at the edge of the substrate (meaning an area formed for holding the substrate by hand).
[0016]
  Claim3The present invention is technically characterized in that the mask is moved to one substrate unit of the multi-piece substrate to perform laser irradiation.
[0017]
  Claim3Then, the mask is moved to one substrate unit of the multi-piece substrate, and laser irradiation is performed. Since the mask is the size of one substrate unit of the multi-piece substrate, the area is smaller than the mask corresponding to the multi-piece substrate, and the influence of expansion and contraction of the mask due to the heat of the laser can be minimized. . Therefore, the accuracy of forming the opening in the substrate can be improved.
[0018]
  Claim4In the present invention, the laser is scanned in the step of irradiating the laser.
[0019]
  Claim4Then, by scanning the laser, even if a linear laser is used, a plurality of fine openings can be formed at a narrow pitch in the substrate through the mask in a short time.
[0020]
  Claim5According to the present invention, a technical feature is that a step of cleaning the mask with a compressed gas or a solvent is provided after the step of irradiating the laser.
[0021]
  Claim5Then, after the step of irradiating the laser, the residue such as a resin piece attached to the mask can be removed by cleaning the mask with a compressed gas or a solvent. Therefore, even if the mask is repeatedly used, an opening defect or the like due to the resin piece attached to the mask does not occur.
[0024]
Preferably, the laser irradiation device is a carbon dioxide laser, and the mask is formed by forming a metal film on the surface of a metal plate. By using a carbon dioxide laser that can easily obtain a high output, a through hole can be formed in the core substrate more easily than other lasers (excimer, UV, YAG). In addition, by forming a metal film on the mask, the mask can withstand long-term use.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
A method for manufacturing a multilayer printed wiring board and a laser processing apparatus according to embodiments of the present invention will be described below with reference to the drawings.
First, the configuration of the multilayer printed wiring board 10 and the laser processing apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 9 and 11 to 15.
FIG. 9 shows a cross-sectional view of the multilayer printed wiring board 10 according to the first embodiment of the present invention. FIG. 11 is an enlarged explanatory view of laser processing according to the first embodiment of the present invention. FIG. 12 shows a top view of the mask. FIG. 13C is a cross-sectional view taken along line AA of the mask shown in FIG. FIG. 14 is an explanatory diagram of the laser processing apparatus according to the first embodiment of the present invention. FIG. 15 shows imaging of a positioning mark by the camera of the optical device.
[0026]
As shown in FIG. 9, in the multilayer printed wiring board 10, through holes 36 are formed in the core substrate 30, and conductor circuits 34 are formed on both surfaces of the core substrate 30. On the core substrate 30, a lower-layer interlayer resin insulation layer 50 in which via holes 60 and conductor circuits 58 are formed is disposed. On the lower interlayer resin insulation layer 50, an upper interlayer resin insulation layer 150 in which via holes 160 and conductor circuits 158 are formed is disposed. A solder resist layer 70 is disposed on the upper interlayer resin insulation layer 150. Openings 71 are formed in the solder resist layer 70, and solder bumps 76 are disposed in the openings 71.
[0027]
The through hole 36 of the multilayer printed wiring board 10 is drilled by a carbon dioxide laser. The openings 48 and 148 of the via holes 60 and 160 and the opening 71 of the solder resist layer 70 are also formed by a carbon dioxide gas laser.
Since fine through holes are formed in the substrate by the laser, the wiring density of the substrate can be increased. In addition, unlike the case where through holes are formed by exposure and development processing, various materials can be used as materials for the interlayer resin insulating layer and the solder resist layer without being limited to the photosensitive resin.
[0028]
Next, a schematic configuration of the laser processing apparatus according to the first embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 14, the multilayer printed wiring board 10 is placed on a table 90 that moves in the XY directions. The XY table 90 is provided with a mesh-like suction port (not shown) for sucking out air having a size corresponding to the multilayer printed wiring board 10. The multilayer printed wiring board 10 has a through hole 33 formed therein. Next, a mask 78 in which a through hole 78a corresponding to the opening formation position of the multilayer printed wiring board 10 is formed on the multilayer printed wiring board 10 is brought into close contact through an alignment process by an optical device described later. is doing.
[0029]
A carbon dioxide laser oscillator 81 is provided on the multilayer printed wiring board 10 to which the mask 78 is in close contact. The carbon dioxide laser oscillator 81 is provided with a lens 82 for expanding the laser light irradiation area. The laser light emitted from the carbon dioxide laser oscillator 81 is applied to the mask 78 through the lens 82, passes through the through hole 78 a, and forms an opening in the multilayer printed wiring board 10. FIG. 11 is an enlarged cross-sectional explanatory diagram showing how the openings are formed by the laser.
[0030]
The output of the carbon dioxide laser is 1 J / cm²The above is preferable.
In the present embodiment, a carbon dioxide laser that easily obtains a high output is used. However, a carbon dioxide laser and another laser (excimer, UV, YAG) may be used together.
[0031]
Next, alignment by the optical device will be described with reference to FIG.
Light is emitted from the illuminator 95 of the mask mounting device 94 toward a positioning mark (not shown) of the multilayer printed wiring board 10 and a mask positioning mark (not shown). Then, the reflected light from both positioning marks is imaged by the camera 92. Based on this, the position of the XY table 90 on which the multilayer printed wiring board 10 is placed is adjusted.
[0032]
Next, the configuration of the mask according to the embodiment of the present invention will be described with reference to FIGS.
The mask 78 shown in FIG. 12 has a plurality of fine through holes 78a formed at a narrow pitch. Thus, by irradiating the mask 78 with a laser, a plurality of fine openings can be formed at a narrow pitch in a lump on the substrate. In addition, positioning marks 79 are provided at the four corners of the surface of the mask 78. The thickness of the mask 78 is preferably 1 mm or less.
[0033]
Next, a mask manufacturing method will be described with reference to FIG.
(1) First, a copper plate is used as the metal material 84 constituting the mask 78. About the metal material 84, metals, such as copper and aluminum, with favorable workability are preferable. In addition to metal, ceramic may be used (FIG. 1A).
[0034]
(2) The metal material 84 is etched into a pattern so as to correspond to the opening formation position of the multilayer printed wiring board, thereby forming a through hole 78a (FIG. 1B). The through-hole 78a may be formed in the metal material 84 by laser.
[0035]
(3) Next, electroless plating is performed on the metal material 84 to form a metal film 86 on the surface of the metal material 84 (FIG. 1C). The metal used for the metal film 86 has good strength such as nickel, chromium, tungsten, etc., has a high melting point, and can withstand a carbon dioxide laser. The metal film 86 allows the mask 78 to withstand long-term use. In addition to the electroless plating, the metal film 86 may be formed by electrolytic plating, sputtering, or a composite thereof.
[0036]
Subsequently, the manufacturing process of the multilayer printed wiring board according to the first embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the multilayer printed wiring board is formed by a semi-additive method.
[0037]
(1) A copper-clad laminate 30A in which 18 μm copper foil 32 is laminated on both surfaces of a substrate 30 made of glass epoxy resin or BT (bismaleimide triazine) resin having a thickness of 0.8 mm is used as a starting material (FIG. 1). (A)). First, a through hole 33 is formed by drilling a hole in the substrate end D of the copper-clad laminate 30A, which is divided and cut along a cut line C in a process described later (FIG. 1B). As shown in FIG. 10, positioning marks 31 are provided at the four corners of the substrate end D of the core substrate 30.
[0038]
(2) Thereafter, the core substrate 30 is placed on the XY table 90 of the laser processing apparatus described above with reference to FIG. Next, the mask 78 in which the plurality of fine through holes 78 a described above with reference to FIG. 12 is formed at a narrow pitch is moved onto the core substrate 30. Then, the positioning mark 31 provided on the core substrate 30 and the positioning mark 79 provided on the mask 78 are optically read by a camera, and the core substrate 30 and the mask 78 are aligned. Thereafter, air between the mask 78 and the core substrate 30 is sucked out from the suction port provided in the XY table 90 through the through hole 33. Thus, the pressure between the mask 78 and the core substrate 30 is reduced, and the mask 78 is brought into close contact with the core substrate 30 (FIG. 1C).
[0039]
(3) A carbon dioxide laser is irradiated from above the core substrate 30 with the mask 78 in close contact with the upper surface. The output of the carbon dioxide laser is 1 J / cm.²The above is preferable. Through this step, a through hole 35 is formed in the core substrate 30 (FIG. 1D). As described above with reference to FIG. 14, the lens 82 for expanding the laser light irradiation area is attached to the laser oscillator 81 that emits the carbon dioxide laser. Therefore, the laser can be irradiated over a wide range, and a plurality of fine through holes 35 can be formed in the core substrate 30 at once.
[0040]
(4) Thereafter, the decompression is released and the mask 78 is removed from the core substrate 30. Then, compressed air is blown onto the mask 78 to remove residues such as resin pieces attached to the mask 78 from the mask 78. Alternatively, the mask 78 may be washed with static electricity or a solvent. Therefore, in the next use, an opening defect or the like due to the resin piece adhering to the mask 78 does not occur.
[0041]
(5) Next, after forming a plating resist on the core substrate 30, an electroless copper plating process is performed to form a through hole 36. Further, the conductor circuit 34 is formed on both surfaces of the substrate by etching the copper foil 32 in a pattern according to a conventional method (FIG. 2A).
[0042]
(6) The substrate on which the conductor circuit 34 is formed is washed with water and dried, and then an etching solution is sprayed on both sides of the substrate 30 to spray the surface of the conductor circuit 34, the surface of the land 36a of the through hole 36, and the inner wall. . As a result, a roughened surface 34α is formed on the surfaces of the conductor circuit 34 and the through hole 36 (FIG. 2B). As an etching solution, a mixture of 10 parts by weight of imidazole copper (II) complex, 7 parts by weight of glycolic acid, 5 parts by weight of potassium chloride and 78 parts by weight of ion-exchanged water was used.
[0043]
(7) The resin filler 40 containing epoxy resin as a main component was applied to both surfaces of the substrate 30 by using a printing machine to fill the space between the conductor circuits 34 or the through holes 36, followed by heat drying. That is, by this step, the resin filler 40 is filled between the conductor circuits 34 or in the through holes 36 (FIG. 2C). At this time, the resin filler 40 is also filled in the through hole 33.
[0044]
(8) Resin-filling the surface of the conductor circuit 34 or the surface of the land 36a of the through-hole 36 on one side of the substrate 30 after the processing of the above (7) by belt sander polishing using belt polishing paper (manufactured by Sankyori Chemical) Polishing was performed so that the agent 40 did not remain, and then buffing was performed to remove scratches due to the belt sander polishing. Such a series of polishing was similarly performed on the other surface of the substrate. Then, the filled resin filler 40 was cured by heating (FIG. 2D).
[0045]
In this way, the surface layer portion of the resin filler 40 filled between the conductor circuits 34 or in the through holes 36 and the roughened surface 34α on the upper surface of the conductor circuit 34 are removed to smooth both surfaces of the substrate. Thereby, a wiring substrate is obtained in which the resin filler 40, the conductor circuit 34, and the through hole 36 are firmly adhered to each other through the roughened surface 34α.
[0046]
(9) Next, the same etching solution as that used in (6) above is sprayed on both surfaces of the substrate 30 by spraying. The roughened surface 34β was formed on the entire surface of the conductor circuit 34 by etching the surface of the conductor circuit 34 once flattened and the surface of the land 36a of the through hole 36 (FIG. 3A).
[0047]
(10) A pressure of 5 kg / cm while raising a thermosetting cycloolefin resin sheet having a thickness of 50 μm to a temperature of 50 to 150 ° C. on both surfaces of the substrate 30 having undergone the step (9).²And an interlayer resin insulating layer 50 made of cycloolefin resin was provided (FIG. 3B). At this time, the degree of vacuum at the time of vacuum pressure bonding was 10 mmHg.
[0048]
(11) Thereafter, a portion of the interlayer resin insulation layer 50 located on the through hole 33 is drilled. As a result, through holes that are directly connected to the through holes 33 are formed in the interlayer resin insulating layer 50 and the resin filler 40 in the through holes 33 that have blocked the through holes 33 (FIG. 3C).
[0049]
(12) Next, as in the step (2), the mask 178 on which a via hole opening pattern 178a described later is formed is aligned on the substrate 30 by the positioning marks provided on both sides. Place. After that, the inside of the through-hole 33 is decompressed, and the mask 178 is brought into close contact with one surface of the substrate 30 (FIG. 3D). Subsequently, as in the step (3), the substrate 30 is irradiated with laser through the mask 178 to form the via hole opening 48. Such a series of steps was similarly performed on the other surface of the substrate (FIG. 4A). The laser used in this step may be any of carbon dioxide, excimer, UV, and YAG. Thereafter, desmear treatment is performed using oxygen plasma.
Further, the mask 178 is cleaned in the same manner as in the step (4).
[0050]
(13) Next, plasma processing is performed using SV-4540 manufactured by Nippon Vacuum Technology Co., Ltd., and the surface of the interlayer resin insulation layer 50 is roughened to form a roughened surface 50β (FIG. 4B). . At this time, argon gas is used as an inert gas, and plasma treatment is performed for 1 minute under the conditions of power 200 W, gas pressure 0.6 Pa, and temperature 70 ° C.
[0051]
(14) Next, using the same apparatus, after replacing the argon gas inside, sputtering using Ni—Cu alloy as a target is performed under conditions of atmospheric pressure 0.6 Pa, temperature 80 ° C., power 200 W, and time 5 minutes. Then, a Ni—Cu alloy layer 52 is formed on the surface of the interlayer resin insulation layer 50 (FIG. 4C). At this time, the thickness of the formed Ni—Cu alloy layer 52 was 0.2 μm.
[0052]
(15) A commercially available photosensitive dry film is pasted on both surfaces of the substrate 30 after the above-described treatment, and a photomask film is placed thereon, and 100 mJ / cm.²After the exposure, a development process is performed with 0.8% sodium carbonate to provide a plating resist 54 having a thickness of 15 μm (FIG. 4D).
[0053]
(16) Next, electrolytic plating is performed under the following conditions to form an electrolytic plating film 56 having a thickness of 15 μm (FIG. 5A). In addition, with this electrolytic plating film 56, the thickness of the portion that becomes the conductor circuit 58 and the plating filling of the portion that becomes the via hole 60 are performed in the steps described later.
[0054]
(Electrolytic plating aqueous solution)
Sulfuric acid 2.24 mol / l
Copper sulfate 0.26 mol / l
Additive (manufactured by Atotech Japan, Kaparaside HL) 19.5 ml / l
[Electrolytic plating conditions]
Current density 1A / dm²
65 minutes
Temperature 22 ± 2 ° C
[0055]
(17) After removing the plating resist 54 with 5% NaOH, the Ni—Cu alloy layer 52 under the plating resist is dissolved and removed by etching using a mixed solution of nitric acid, sulfuric acid and hydrogen peroxide, and Ni—Cu A conductor circuit 58 and a via hole 60 having a thickness of 16 μm formed of the alloy layer 52 and the electrolytic plating film 56 are formed (FIG. 5B).
[0056]
(18) Subsequently, by repeating the steps (10) to (17), an upper conductor circuit 158 (including the via hole 160) is formed (FIG. 5C).
[0057]
(19) Next, a photosensitizing agent obtained by acrylated 50% of an epoxy group of a cresol novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.) dissolved in diethylene glycol dimethyl ether (DMDG) to a concentration of 60% by weight. 46.67 parts by weight of oligomer (molecular weight 4000), 80 parts by weight of bisphenol A type epoxy resin dissolved in methyl ethyl ketone (manufactured by Yuka Shell, trade name: Epicoat 1001), 15 parts by weight of imidazole curing agent (manufactured by Shikoku Kasei Co., Ltd.) , Trade name: 2E4MZ-CN) 1.6 parts by weight, polyfunctional acrylic monomer (manufactured by Kyoei Chemical Co., Ltd., trade name: R604) which is a photosensitive monomer, polyvalent acrylic monomer (manufactured by Kyoei Chemical Co., Ltd., product) Name: DPE6A) 1.5 parts by weight, dispersion antifoaming agent (manufactured by San Nopco, trade name: S-65) 0.7 A weight part is put into a container, and a mixed composition is prepared by stirring and mixing. 2.0 parts by weight of benzophenone (manufactured by Kanto Chemical Co., Inc.) as a photoweight initiator and Michler's ketone as a photosensitizer for the mixed composition. 0.2 parts by weight (manufactured by Kanto Chemical Co., Inc.) is added to obtain a solder resist composition 70 (organic resin insulating material) having a viscosity adjusted to 2.0 Pa · s at 25 ° C.
In addition, the viscosity measurement was based on rotor No. 3 in the case of 60 rpm with a B type viscometer (manufactured by Tokyo Keiki Co., Ltd., DVL-B type).
[0058]
(20) The solder resist composition 70α was applied in a thickness of 20 μm on both surfaces of the multilayer printed wiring board obtained in the above (18) (FIG. 6A). Subsequently, the solder resist composition 70α is cured by heat treatment at 80 ° C. for 1 hour, 100 ° C. for 1 hour, 120 ° C. for 1 hour, and 150 ° C. for 3 hours.
Thereafter, a portion of the solder resist composition 70α located on the through hole 33 is drilled to form a through hole directly connected to the through hole 33 in the solder resist composition 70α that has blocked the through hole 33 ( FIG. 6 (B)).
Moreover, you may laminate | stack the thing formed as a film which made the soldering resist layer the semi-hardened B stage shape by pressurization and heat pressurization.
In addition to the above, as the solder resist composition, a resin composition composed of a cresol novolak type epoxy resin, a phenoxy resin, and a curing agent (an amine curing agent or an imidazole curing agent) may be used.
[0059]
(21) Next, in the same manner as in the above step (2), the mask 378 in which the pattern 378a of the solder resist opening is formed is aligned on the multilayer printed wiring board by the positioning marks provided on both sides, Place. Thereafter, the inside of the through-hole 33 is decompressed to bring the mask 378 into close contact with the multilayer printed wiring board (FIG. 7A). Then, the multilayer printed wiring board is irradiated with laser through the mask 378 to form an opening 71 of the solder resist. The laser used in this step may be any of carbon dioxide, excimer, UV, and YAG. Further, the mask 378 is cleaned in the same manner as in the step (4).
As a result, a solder resist layer (organic resin insulating layer) 70 having a thickness of 20 μm and having an opening 71 in the solder pad portion (including the via hole and its land portion) is formed (FIG. 7B).
[0060]
(22) Next, the substrate on which the solder resist layer (organic resin insulating layer) 70 is formed is nickel chloride (2.3 × 10^-1mol / l), sodium hypophosphate (2.8 × 10 6)^-1mol / l), sodium citrate (1.6 × 10^-1The nickel plating layer 72 having a thickness of 5 μm is formed in the opening 71 by immersing in an electroless nickel plating solution having a pH of 4.5 containing 1 mol / l) (FIG. 8A).
[0061]
(23) Further, the substrate was made of potassium gold cyanide (7.6 × 10^-3mol / l), ammonium chloride (1.9 × 10^-1mol / l), sodium citrate (1.2 × 10^-1mol / l), sodium hypophosphite (1.7 × 10^-1In order to form a 0.03 μm thick gold plating layer 74 on the nickel plating layer 72 by immersing in an electroless plating solution containing (mol / l) at 80 ° C. for 7.5 minutes, the via hole 160 and the conductor Solder pads 75 are formed in the circuit 158 (FIG. 8B).
[0062]
(24) After that, solder bumps (solder bodies) 76 are formed by printing solder paste in the openings 71 of the solder resist layer 70 and reflowing at 200 ° C. Finally, the substrate end D shown in FIG. 10 is divided and cut along the cut line C and cut off. Thereby, the multilayer printed wiring board 10 which has the solder bump 76 can be obtained (refer FIG. 9).
[0063]
Next, the multilayer printed wiring board 20 according to the second embodiment of the present invention will be described with reference to FIG. In 1st Embodiment mentioned above, the case where BGA was arrange | positioned demonstrated. The second embodiment is substantially the same as the first embodiment, but is configured in a PGA system in which connection is established via conductive connection pins 96 as shown in FIG.
[0064]
A method for manufacturing a multilayer printed wiring board will be described. Here, the A.M. used for the manufacturing method of the multilayer printed wiring board of 2nd Embodiment is demonstrated. A resin film for an interlayer resin insulation layer; The resin filler will be described.
[0065]
A. Preparation of resin film for interlayer resin insulation layer
30 parts by weight of bisphenol A type epoxy resin (epoxy equivalent 469, Epicoat 1001 manufactured by Yuka Shell Epoxy), cresol novolak type epoxy resin (epoxy equivalent 215, Epicron N-673 manufactured by Dainippon Ink & Chemicals), triazine 30 parts by weight of a structure-containing phenol novolak resin (phenolic hydroxyl group equivalent 120, Phenolite KA-7052 manufactured by Dainippon Ink & Chemicals, Inc.) was dissolved in 20 parts by weight of ethyl diglycol acetate and 20 parts by weight of solvent naphtha with stirring. Thereto, terminal epoxidized polybutadiene rubber (Nagase Kasei Kogyo Denarex R-45EPT) 15 parts by weight, 2-phenyl-4,5-bis (hydroxymethyl) imidazole pulverized product 1.5 parts by weight, finely pulverized silica 2 parts by weight , Silicon Added to prepare an epoxy resin composition agent 0.5 parts by weight.
The obtained epoxy resin composition was applied on a PET film having a thickness of 38 μm using a roll coater so that the thickness after drying was 50 μm, and then dried at 80 to 120 ° C. for 10 minutes, whereby an interlayer resin was obtained. A resin film for an insulating layer was produced.
[0066]
B. Preparation of resin filler
100 parts by weight of bisphenol F type epoxy monomer (manufactured by Yuka Shell Co., Ltd., molecular weight: 310, YL983U), SiO having an average particle diameter of 1.6 μm and a maximum particle diameter of 15 μm or less coated with a silane coupling agent on the surface₂170 parts by weight of spherical particles (manufactured by Adtech, CRS 1101-CE) and 1.5 parts by weight of a leveling agent (Perenol S4, manufactured by San Nopco) are placed in a container and mixed by stirring. A 49 Pa · s resin filler was prepared. As the curing agent, 6.5 parts by weight of an imidazole curing agent (manufactured by Shikoku Kasei Co., Ltd., 2E4MZ-CN) was used.
[0067]
Next, a method for manufacturing a multilayer printed wiring board according to the second embodiment of the present invention will be described with reference to FIGS.
[0068]
(1) A copper-clad laminate 30A in which 18 μm copper foil 32 is laminated on both surfaces of a substrate 30 made of glass epoxy resin or BT (bismaleimide triazine) resin having a thickness of 0.8 mm is used as a starting material (FIG. 16). (A)). First, in the later-described process of the copper-clad laminate 30A, a drill hole is drilled in the substrate end D that is cut by being cut by the cut line C to form the through hole 33 (FIG. 16B). As shown in FIG. 10, positioning marks 31 are provided at the four corners of the substrate end D of the core substrate 30.
[0069]
(2) Thereafter, the core substrate 30 is placed on the XY table 90 of the laser processing apparatus described above with reference to FIG. Next, the mask 78 in which a plurality of fine through holes 78a are formed at a narrow pitch is moved onto the core substrate 30 as in the first embodiment. Then, the positioning mark 31 provided on the core substrate 30 and the positioning mark 79 provided on the mask 78 are optically read by a camera, and the core substrate 30 and the mask 78 are aligned. Thereafter, air between the mask 78 and the core substrate 30 is sucked out from the suction port provided in the XY table 90 through the through hole 33. Accordingly, the pressure between the mask 78 and the core substrate 30 is reduced, and the mask 78 is brought into close contact with the core substrate 30 (FIG. 16C).
[0070]
(3) A carbon dioxide laser is irradiated from above the core substrate 30 with the mask 78 in close contact with the upper surface. The output of the carbon dioxide laser is 1 J / cm.²The above is preferable. Through this step, a through hole 35 is formed in the core substrate 30 (FIG. 16D). As described above with reference to FIG. 14, the lens 82 for expanding the laser light irradiation area is attached to the laser oscillator 81 that emits the carbon dioxide laser. Therefore, the laser can be irradiated over a wide range, and a plurality of fine through holes 35 can be formed in the core substrate 30 at once.
[0071]
(4) Thereafter, the decompression is released and the mask 78 is removed from the core substrate 30. Then, compressed air can be blown onto the mask 78 to remove residues such as resin pieces attached to the mask 78 from the mask 78. Alternatively, electrostatic removal or cleaning with a solvent may be used. Therefore, in the next use, an opening defect or the like due to the resin piece adhering to the mask 78 does not occur.
[0072]
(5) Next, after forming a plating resist on the core substrate 30, an electroless copper plating process is performed to form a through hole 36. Further, the copper foil 32 is etched into a pattern according to a conventional method, thereby forming a conductor circuit 34 on both surfaces of the substrate (FIG. 17A).
[0073]
(6) The substrate on which the conductor circuit 34 is formed is washed with water and dried, followed by NaOH (10 g / l), NaClO₂(40 g / l), Na_ThreePO_FourBlackening treatment using an aqueous solution containing (6 g / l) as a blackening bath (oxidation bath), and NaOH (10 g / l), NaBH_FourA reduction treatment using an aqueous solution containing (6 g / l) as a reduction bath is performed to form a roughened surface 37α on the surfaces of the conductor circuit 34 and the through hole 36 (FIG. 17B).
[0074]
(7) After preparing the resin filler described in B above, within 24 hours after adjustment by the following method, within the through hole 36 and on the one side of the substrate 30 where the conductor circuit 34 is not formed and the outer edge of the conductor circuit 34 A layer of the resin filler 40 was formed on the part.
That is, first, a resin filler was pushed into the through hole 36 using a squeegee, and then dried at 100 ° C. for 20 minutes. Next, a mask having an opening corresponding to a portion where the conductor circuit 34 is not formed is placed on the substrate 30, and a layer of the resin filler 40 is formed on the portion where the conductor circuit 34 is not formed using a squeegee. And dried at 100 ° C. for 20 minutes (FIG. 17C). Further, the resin filler 40 is also filled in the through hole 33.
[0075]
(8) The surface of the conductor circuit 34 or the surface of the land 36a of the through hole 36 is obtained by subjecting one side of the substrate 30 having been subjected to the processing of (7) above to belt sander polishing using # 600 belt polishing paper (manufactured by Sankyo Rikagaku). The resin filler 40 is polished so as not to remain. Next, buffing for removing scratches caused by the belt sander polishing was performed. Such a series of polishing was similarly performed on the other surface of the substrate. Next, heat treatment was performed at 100 ° C. for 1 hour and at 150 ° C. for 1 hour to heat and cure the resin filler 40 (FIG. 17D).
[0076]
In this way, the surface layer portion of the resin filler 40 and the surface of the conductor circuit 34 formed in the through hole 36 and the portion where the conductor circuit 34 is not formed are flattened. As a result, a wiring board is obtained in which the resin filler 40, the conductor circuit 34, and the through hole 36 are firmly adhered via the roughened surface 37α. That is, by this step, the surface of the resin filler 40 and the surface of the conductor circuit 34 are flush.
[0077]
(9) Next, the substrate 30 that has been subjected to the process (8) is washed with water and soft-etched. Next, an etching solution is sprayed on both surfaces of the substrate 30 to etch the surface of the conductor circuit 34 and the land surface and inner wall of the through hole 36, thereby forming a roughened surface 37β on the entire surface of the conductor circuit 34. (FIG. 18A).
As an etchant, an etchant (MEC Etch Bond, manufactured by MEC Co.) consisting of 10 parts by weight of imidazole copper (II) complex, 7 parts by weight of glycolic acid, and 5 parts by weight of potassium chloride was used.
[0078]
(10) A resin film for an interlayer resin insulation layer that is slightly larger than the substrate 30 produced in A is placed on both sides of the substrate 30 that has undergone step (9) above. Then, the resin film for the interlayer resin insulation layer and the substrate 30 are subjected to a pressure of 4 kgf / cm.²Temporary pressure bonding is performed under the conditions of a temperature of 80 ° C. and a pressure bonding time of 10 seconds, and the resin film for the interlayer resin insulation layer is cut into the size of the substrate 30. Further, the interlayer resin insulating layer 50 is formed by pasting using a vacuum laminator apparatus by the following method (FIG. 18B). That is, a resin film for an interlayer resin insulation layer is placed on the substrate 30 with a degree of vacuum of 0.5 Torr and a pressure of 4 kgf / cm.²The film was subjected to main pressure bonding under conditions of a temperature of 80 ° C. and a pressure bonding time of 60 seconds, and then thermally cured at 170 ° C. for 30 minutes.
[0079]
(11) Thereafter, a portion of the interlayer resin insulation layer 50 located above the through hole 33 is drilled to close the through hole 33 and the resin filler 40 in the through hole 33. Then, a through hole directly connected to the through hole 33 is formed (FIG. 18C).
[0080]
(12) Next, in the same manner as in the above step (2), a mask 178 on which a via hole opening pattern 178a described later is formed is aligned on the substrate 30 by positioning marks provided on both sides. , Place. Thereafter, the inside of the through-hole 33 is decompressed, and the mask 178 is brought into close contact with one surface of the substrate 30 (FIG. 18D). Subsequently, as in the step (3), the substrate 30 is irradiated with laser through the mask 178 to form the via hole opening 48. Such a series of steps was similarly performed on the other surface of the substrate (FIG. 19A). The laser used in this step may be any of carbon dioxide, excimer, UV, and YAG. Thereafter, desmear treatment is performed using oxygen plasma.
Further, the mask 178 is cleaned in the same manner as in the step (4).
[0081]
(13) Then, the substrate 30 on which the via hole opening 48 is formed is immersed in an 80 ° C. solution containing 60 g / l permanganic acid for 10 minutes. Thereby, the epoxy resin particles present on the surface of the interlayer resin insulation layer 50 are dissolved and removed, so that the surface of the interlayer resin insulation layer 50 is roughened and a roughened surface 50β is formed on the surface of the interlayer resin insulation layer 50 ( FIG. 19 (B)).
[0082]
(14) Next, the substrate after the above treatment is immersed in a neutralization solution (manufactured by Shipley Co., Ltd.) and then washed with water. Further, by applying a palladium catalyst to the surface of the roughened substrate (roughening depth 3 μm), catalyst nuclei are attached to the surface of the interlayer resin insulation layer 50 and the inner wall surface of the via hole opening 48. It was.
[0083]
(15) Next, the substrate 30 is immersed in an electroless copper plating aqueous solution having the following composition to form an electroless copper plating film 53 having a thickness of 0.6 to 3.0 μm over the entire rough surface (FIG. 19). (C)).
[0084]
[Electroless plating aqueous solution]
NiSO_Four                      0.003 mol / l
Tartaric acid 0.200 mol / l
Copper sulfate 0.030 mol / l
HCHO 0.050 mol / l
NaOH 0.100 mol / l
α, α'-bipyridyl 40 mg / l
Polyethylene glycol (PEG) 0.10 g / l
[Electroless plating aqueous solution]
40 minutes at 35 ° C liquid temperature
[0085]
(16) A commercially available photosensitive dry film is attached to the electroless copper plating film 53 on both surfaces of the substrate 30 after the above processing. Then, a photomask film is placed and 100 mJ / cm²After the exposure, a development process is performed with 0.8% sodium carbonate to provide a plating resist 54 having a thickness of 30 μm (FIG. 19D).
[0086]
(17) Next, the substrate 30 is washed and degreased with water at 50 ° C., washed with water at 25 ° C., and further washed with sulfuric acid. Thereafter, electrolytic copper plating is performed under the following conditions to form an electrolytic copper plating film 56 having a thickness of 20 μm (FIG. 20A).
[0087]
(Electrolytic plating aqueous solution)
Sulfuric acid 2.24 mol / l
Copper sulfate 0.26 mol / l
Additive (manufactured by Atotech Japan, Kaparaside HL) 19.5 ml / l
[Electrolytic plating conditions]
Current density 1A / dm²
65 minutes
Temperature 22 ± 2 ° C
[0088]
(18) After removing the plating resist 54 with 5% NaOH, the electroless copper plating film 53 under the plating resist is dissolved and removed by etching using a mixed solution of sulfuric acid and hydrogen peroxide. A conductor circuit 58 and a via hole 60 having a thickness of 18 μm are formed of 53 and an electrolytic plating film 56 (FIG. 20B).
[0089]
(19) The same treatment as in (9) is performed, and a roughened surface 58α is formed by an etching solution containing a cupric complex and an organic acid (FIG. 20C).
[0090]
(20) Subsequently, by repeating the steps (10) to (19), a further upper conductor circuit 158 (including the via hole 160) is formed (FIG. 20D).
[0091]
(21) A solder resist composition 70α similar to that of the first embodiment is applied to both surfaces of the multilayer printed wiring board with a thickness of 20 μm (FIG. 21A). Subsequently, the solder resist composition 70α is cured by heat treatment at 80 ° C. for 1 hour, 100 ° C. for 1 hour, 120 ° C. for 1 hour, and 150 ° C. for 3 hours. Thereafter, a portion of the solder resist composition 70α located above the through hole 33 is drilled to form a through hole directly connected to the through hole 33 in the solder resist composition 70α that has blocked the through hole 33. (FIG. 21 (B)).
[0092]
(22) Next, as in the step (2), the mask 378 in which the pattern 378a of the solder resist opening is formed is aligned on the multilayer printed wiring board by the positioning marks provided on both sides, Place. Thereafter, the inside of the through hole 33 is decompressed, and the mask 378 is brought into close contact with the multilayer printed wiring board (FIG. 22A). Then, the multilayer printed wiring board is irradiated with laser through the mask 378 to form solder resist openings 71U and 71D. The laser used in this step may be any of carbon dioxide, excimer, UV, and YAG. Further, the mask 378 is cleaned in the same manner as in the step (4).
Thus, a solder resist layer (organic resin insulating layer) 70 having a thickness of 20 μm and having openings 71U and 71D in the solder pad portion (including the via hole and its land portion) is formed (FIG. 22B).
[0093]
(23) Next, the substrate on which the solder resist layer (organic resin insulating layer) 70 is formed is nickel chloride (2.3 × 10^-1mol / l), sodium hypophosphate (2.8 × 10 6)^-1mol / l), sodium citrate (1.6 × 10^-1The nickel plating layer 72 having a thickness of 5 μm is formed in the opening 71 by immersing in an electroless nickel plating solution containing 0.5 mol / l) of pH = 4.5 (FIG. 23A).
[0094]
(24) Further, the substrate was made of potassium gold cyanide (7.6 × 10^-3mol / l), ammonium chloride (1.9 × 10^-1mol / l), sodium citrate (1.2 × 10^-1mol / l), sodium hypophosphite (1.7 × 10^-1In order to form a 0.03 μm thick gold plating layer 74 on the nickel plating layer 72 by immersing in an electroless plating solution containing (mol / l) at 80 ° C. for 7.5 minutes, the via hole 160 and the conductor Solder pads 75 are formed in the circuit 158 (FIG. 23B).
[0095]
(25) Thereafter, a solder paste containing tin-lead is printed in the opening 71U of the solder resist layer 70 on the surface on which the IC chip of the substrate is placed. Further, a solder paste is printed as the conductive adhesive 97 in the opening 71D on the other surface. Next, the conductive connection pin 96 is attached to and supported by an appropriate pin holding device, and the fixing portion 98 of the conductive connection pin 96 is brought into contact with the conductive adhesive 97 in the opening 71D. Then, reflow is performed to fix the conductive connection pin 96 to the conductive adhesive 97. As a method for attaching the conductive connection pin 96, a conductive adhesive 97 formed in a ball shape or the like is put into the opening 71D, or the conductive adhesive 97 is joined to the fixing portion 98 to conduct the conductive. May be attached and then reflowed.
Finally, the substrate end D shown in FIG. 10 is divided and cut along the cut line C and cut off. Thereby, the multilayer printed wiring board 20 which has the solder bump 76 and the electroconductive connection pin 96 can be obtained (refer FIG. 24).
[0096]
Next, a third embodiment of the present invention will be described with reference to FIGS.
FIG. 25 is an explanatory diagram of a laser processing apparatus and a laser processing method for a multilayer printed wiring board according to the third embodiment of the present invention. FIG. 26 is a top view of the multi-piece substrate shown in FIG. FIG. 27 is a top view of the mask shown in FIG.
[0097]
First, a schematic configuration of a substrate and a mask according to a third embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 26, a mask suction through-hole 133 is provided at the substrate end E of the multi-cavity core substrate 130 and the cutting portion G between the substrates. In addition, positioning marks 131 are provided at the four corners of the multi-piece substrate 130.
As shown in FIG. 27, a plurality of fine through holes 478a are formed in the mask 478 corresponding to the multi-piece substrate 130. In addition, positioning marks 479 are provided at the four corners of the mask 478.
[0098]
Next, a laser processing apparatus and laser processing method for a multilayer printed wiring board according to a third embodiment of the present invention will be described with reference to FIG.
The light emitted from the laser oscillator 181 enters the galvano head 170 through a transfer mask 182 for sharpening the focal point on the substrate. The galvano head 170 is composed of a pair of galvano mirrors, a galvano mirror 174X that scans laser light in the X direction and a galvano mirror 174Y that scans in the Y direction. It is driven by motors 172X and 172Y. The motors 172X and 172Y are configured to adjust the angles of the mirrors 174X and 174Y according to a control command from a control device (not shown) and to send a detection signal from a built-in encoder to the computer side.
[0099]
The laser light is scanned in the XY direction via the galvanometer mirrors 174X and 174Y, passes through the f-θ lens 176, and is taken in a large number through the mask 478 as in the first embodiment of the present invention. A through hole is formed in the core substrate 130. The multi-piece substrate 130 is placed on an XY table 90 that moves in the XY direction.
[0100]
In the first and second embodiments, as described above with reference to FIG. 14, the lens 82 that expands the irradiation area is used in the laser oscillator 81. This irradiation area is a circle or an ellipse. On the other hand, in the laser processing apparatus of the third embodiment, as shown in FIG. 25, the mask is irradiated with a linear laser as shown in FIG. Openings are formed in the insulating layer and the solder resist layer in a short time.
[0101]
In the first and second embodiments, an opening and a through hole are formed on one substrate via a mask. In contrast, in the third embodiment, as shown in FIG. 25, a multi-piece substrate 130 is provided with a mask 478 in which a through hole 478a corresponding to the opening formation position of the multi-piece substrate 130 is formed. Thus, an opening and a through hole are formed. Thereby, openings and through holes are formed in a plurality of substrates at once.
[0102]
Subsequently, a fourth embodiment of the present invention will be described with reference to FIGS.
FIG. 28 is an explanatory diagram of a laser processing method for a multilayer printed wiring board according to the fourth embodiment of the present invention. FIG. 29 is a plan view showing a state where a mask is placed on the multi-piece substrate shown in FIG.
[0103]
First, a schematic configuration of a substrate and a mask according to a fourth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 29, a mask suction through-hole 133 is provided at the cut end F of each substrate of the multi-chip substrate 130. In addition, positioning marks 131 are provided at the four corners of the cutting end F of one substrate unit. On the other hand, the mask 578 is formed in a size corresponding to three of the multiple substrates 130. A plurality of fine through holes 578a are formed in the mask 578, and positioning marks 579 are provided at the four corners.
[0104]
Then, the laser processing method of the multilayer printed wiring board concerning 4th Embodiment of this invention is demonstrated with reference to FIG.
As shown in FIG. 28 in substantially the same manner as in the first embodiment of the present invention, in the fourth embodiment, the multi-chip substrate 130 is made to correspond to three of the multi-chip substrates 130. Then, the mask 578 is placed. The mask 578 is brought into close contact with the substrate side through the through-hole 133, and then the laser is irradiated through the mask 578 and the XY table 90 is moved to make a through hole in each of the three substrates. Set up. When the through holes are drilled in the three substrates, the mask 578 is moved to the next three substrates for positioning, and laser irradiation is performed. As for laser irradiation, openings and through holes may be formed while scanning a linear laser as in the third embodiment.
[0105]
Since the mask 578 according to the fourth embodiment has a size of a unit of three substrates of a multi-piece substrate, the mask 578 has a smaller area than the mask corresponding to the multi-piece substrate of the third embodiment, and the heat of the laser. The influence of expansion and contraction of the mask due to can be reduced. Therefore, the accuracy of forming the opening in the substrate can be improved.
[0106]
Next, a fifth embodiment of the present invention will be described with reference to FIGS.
FIG. 30 is an explanatory diagram of a laser processing method for a multilayer printed wiring board according to the fifth embodiment of the present invention. FIG. 31 is a plan view showing a state where the mask is placed on the substrate shown in FIG.
[0107]
The fifth embodiment is the same as the above-described fourth embodiment. However, as shown in FIG. 30, a mask 678 corresponding to one substrate unit of the multi-piece substrate 130 is used, and a large number of the masks 678 are used. The substrate is moved to one substrate unit of the taking substrate 130 and irradiated with laser.
Since the mask 678 is the size of one substrate unit of the multi-chip substrate 130, the area of the mask 678 is smaller than that of the mask corresponding to the multi-chip substrate 130, and the expansion and contraction of the mask due to the heat of the laser is also affected. Can be minimized. Therefore, it is possible to improve the accuracy of forming openings and through holes in the substrate. However, since the resin used in the embodiment of the present application has a melting point of 300 ° C. or lower, the resin is dissolved and carbonized when a temperature of 350 ° C. or higher is applied.
[0108]
【The invention's effect】
In the present invention, as described above, the mask and the substrate are aligned, and then the mask is brought into close contact with the substrate side, and then an opening is formed in the substrate through the mask with a laser. By bringing the mask into close contact with the substrate side, a plurality of fine openings can be accurately formed in the substrate with a narrow pitch with a laser without shifting the mask. For this reason, it becomes possible to increase the wiring density of the multilayer printed wiring board.
[Brief description of the drawings]
FIGS. 1A, 1B, 1C, and 1D are manufacturing process diagrams of a multilayer printed wiring board according to a first embodiment of the present invention.
2A, 2B, 2C, and 2D are manufacturing process diagrams of a multilayer printed wiring board according to the first embodiment of the present invention. FIG.
3A, 3B, 3C, and 3D are manufacturing process diagrams of a multilayer printed wiring board according to the first embodiment of the present invention.
4A, 4B, 4C, and 4D are manufacturing process diagrams of the multilayer printed wiring board according to the first embodiment of the present invention. FIG.
5A, 5B, and 5C are manufacturing process diagrams of a multilayer printed wiring board according to the first embodiment of the present invention.
6A and 6B are manufacturing process diagrams of the multilayer printed wiring board according to the first embodiment of the present invention.
7A and 7B are manufacturing process diagrams of the multilayer printed wiring board according to the first embodiment of the present invention.
8A and 8B are manufacturing process diagrams of the multilayer printed wiring board according to the first embodiment of the present invention.
FIG. 9 is a cross-sectional view of the multilayer printed wiring board according to the first embodiment of the present invention.
FIG. 10 is a top view of the core substrate according to the first embodiment of the present invention.
FIG. 11 is an enlarged explanatory view of a state of laser processing of the multilayer printed wiring board according to the first embodiment of the present invention.
FIG. 12 is a plan view of a mask according to the first embodiment of the present invention.
13A, 13B, and 13C are manufacturing process diagrams of the mask shown in FIG.
FIG. 14 is an explanatory diagram of the laser processing apparatus according to the first embodiment of the present invention.
FIG. 15 shows imaging of a positioning mark by the camera of the optical device.
16 (A), (B), (C), and (D) are manufacturing process diagrams of a multilayer printed wiring board according to a second embodiment of the present invention.
17 (A), (B), (C), and (D) are manufacturing process diagrams of a multilayer printed wiring board according to a second embodiment of the present invention.
18A, 18B, 18C, and 18D are manufacturing process diagrams of the multilayer printed wiring board according to the second embodiment of the present invention.
19A, 19B, 19C, and 19D are manufacturing process diagrams of a multilayer printed wiring board according to the second embodiment of the present invention.
20A, 20B, 20C, and 20D are manufacturing process diagrams of a multilayer printed wiring board according to a second embodiment of the present invention.
FIGS. 21A and 21B are manufacturing process diagrams of a multilayer printed wiring board according to a second embodiment of the present invention.
22A and 22B are manufacturing process diagrams of the multilayer printed wiring board according to the second embodiment of the present invention.
23A and 23B are manufacturing process diagrams of the multilayer printed wiring board according to the second embodiment of the present invention.
FIG. 24 is a cross-sectional view of a multilayer printed wiring board according to the second embodiment of the present invention.
FIG. 25 is an explanatory diagram of a laser processing apparatus for a multilayer printed wiring board according to a third embodiment of the present invention.
FIG. 26 is a plan view of a multi-piece substrate according to a third embodiment of the present invention.
FIG. 27 is a plan view of a mask according to a third embodiment of the present invention.
FIG. 28 is an explanatory diagram of laser processing of the multilayer printed wiring board according to the fourth embodiment of the present invention.
FIG. 29 is a plan view showing a state where a mask is placed on the multi-piece substrate shown in FIG. 28;
FIG. 30 is an explanatory diagram of laser processing of the multilayer printed wiring board according to the fifth embodiment of the present invention.
FIG. 31 is a plan view showing a state where a mask is placed on the multi-piece substrate shown in FIG. 30;
[Explanation of symbols]
30 core substrate
31 Positioning mark (board side)
33 Through hole
34 Conductor circuit
36 Bahia Hall
50 Interlayer resin insulation layer
58 Conductor circuit
60 Bahia Hall
70 Solder resist layer
71U, 71D opening
72 Nickel plating layer
74 Gold plating layer
76 Solder bump
78 Mask
78a through hole
79 Positioning mark (mask side)
81 Laser oscillator
82 Optical system (lens)
96 Conductive connection pins
130 Multi-chip substrate
150 Interlayer resin insulation layer
158 Conductor circuit
160 Viahole
178 mask
178a through hole
378 mask
378a through hole
478 mask
478a through hole
479 Positioning mark (mask side)
578 mask
678 mask

Claims (5)

A method for producing a multilayer printed wiring board comprising at least the following steps (A) to (C):
(A) a step of aligning the substrate and the mask from a positioning mark provided on the substrate and a positioning mark provided on a mask having an opening;
(B) a step of adsorbing the mask to the substrate side through a through hole formed in the substrate;
(C) A step of irradiating the mask with a laser to form a plurality of through holes in the substrate. A method for producing a multilayer printed wiring board comprising at least the following steps (A) to (C):
(A) a step of aligning the substrate and the mask from a positioning mark provided on a substrate for multi-cavity and a positioning mark provided on a mask having an opening ,
Adsorbing the mask to the substrate side through a through-hole formed in the substrate ;
(B) irradiating the mask with a laser to form a plurality of through holes in the substrate;
(C) A step of moving the mask, moving the multi-piece substrate, and performing the steps (A) and (B).   3. The method of manufacturing a multilayer printed wiring board according to claim 2, wherein the mask is moved to one substrate unit of the substrate for picking up multiple pieces, and laser irradiation is performed. In the step of irradiating the laser, according to claim. 1 to any one multilayer printed wiring board manufacturing method of 3, wherein the scanning the laser. After the step of irradiating the laser, according to claim 1 any one of a method for manufacturing a multilayer printed wiring board 4, characterized in that it comprises the step of cleaning the mask by compressed gas or solvent.

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