Source: http://patents.com/us-9788439.html
Timestamp: 2018-12-10 21:49:05
Document Index: 606538988

Matched Legal Cases: ['arts 51', 'arts 52', 'arts 53', 'ART 7', 'ART 31', 'ART 32']

US Patent # 9,788,439. Manufacturing method of multilayer printed wiring board - Patents.com
United States Patent 9,788,439
Family ID: 1000002881960
15/022,292
PCT/JP2014/058587
WO2015/040878
US 20160295707 A1 Oct 6, 2016
Current CPC Class: H05K 3/4069 (20130101); H05K 1/0298 (20130101); H05K 1/092 (20130101); H05K 1/115 (20130101); H05K 3/06 (20130101); H05K 3/4623 (20130101); H05K 3/4617 (20130101); Y10T 29/49165 (20150115); H05K 2201/0355 (20130101); H05K 2203/1383 (20130101); Y10T 29/49128 (20150115)
Current International Class: H05K 3/20 (20060101); H05K 1/02 (20060101); H05K 1/09 (20060101); H05K 3/46 (20060101); H05K 3/40 (20060101); H05K 1/11 (20060101); H05K 3/06 (20060101)
Field of Search: ;29/830,831,846,852 ;174/255,262
9148963 September 2015 Matsuda
Notiication of Resson for Rejection, dated Feb. 7, 2017, with English translation (10 pages). cited by applicant .
International Search Report, dated Apr. 28 2014 (2 pages). cited by applicant.
1. A manufacturing method of a multilayer printed wiring board comprising: attaching an adhesive protective film having a weak adhesive layer formed on one side thereof to a single-sided metal-foiled laminate sheet having a first insulating resin film and a first metal foil on a front face of the first insulating resin film in such a way that the weak adhesive layer contacts with a rear face of the first insulating resin film; forming a bottomed via hole that has a bottom face with the first metal foil exposed therefrom by partially removing the adhesive protective film and the first insulating resin film; first printing of filling a conductive paste into the bottomed via hole by a printing method; peeling off the adhesive protective film from the first insulating resin film and causing a part of the conductive paste filled in the bottomed via hole to protrude from the first insulating resin film to obtain a first wiring substrate; forming, on a double-sided metal-foiled laminate sheet having a second insulating resin film and second and third metal foils respectively provided on a front face and a rear face of the second insulating resin film, a piercing mask by patterning the second metal foil; forming an adhesive protective layer including an adhesive-agent layer that covers the front face of the second insulating resin film and buries the patterned second metal foil and a protective film that is laminated on the adhesive-agent layer; forming a bottomed step via hole that has a middle part with the piercing mask exposed therefrom and a bottom face with the third metal foil exposed therefrom by partially removing the adhesive protective layer and the second insulating resin film; second printing of filling a conductive paste into the bottomed step via hole by a printing method; peeling off the protective film from the adhesive-agent layer and causing a part of the conductive paste filled in the bottomed step via hole to protrude from the adhesive-agent layer to obtain a second wiring substrate; and laminating in which the first wiring substrate and the second wiring substrate are laminated in such a way that a protruding part of the conductive paste filled in the bottomed via hole of the first wiring substrate comes into contact with a protruding part of the conductive paste filled in the bottomed step via hole of the second wiring substrate, and the laminated first and second wiring substrates are heated to be integrated with each other.
2. The manufacturing method of a multilayer printed wiring board according to claim 1, wherein heating is performed at a predetermined laminating-process temperature in the laminating, thereby achieving metal bonding among metal particles included in the conductive pastes filled in the bottomed via hole and the bottomed step via hole and metal bonding among the metal particles and the first to third metal foils, and substantially completing heat-curing reaction of resin binder included in the conductive pastes and the adhesive-agent layer.
3. The manufacturing method of a multilayer printed wiring board according to claim 1, wherein in the first printing and/or the second printing, a conductive paste that includes metal particles made of In, SnIn, or SnBi is used.
4. The manufacturing method of a multilayer printed wiring board according to claim 1, wherein the first to third metal foils are copper foils, and in the first printing and/or the second printing, a conductive paste that includes metal particles made of Sn, Zn, Al, Ag, Ni, Cu or an alloy of these metals is used.
5. The manufacturing method of a multilayer printed wiring board according to claim 1, wherein before the laminating, the first metal foil and the third metal foil are patterned to form respective predetermined wiring patterns.
6. The manufacturing method of a multilayer printed wiring board according to claim 1, wherein after the laminating, the first metal foil and the third metal foil are patterned to form respective predetermined wiring patterns.
7. The manufacturing method of a multilayer printed wiring board according to claim 6, wherein the first metal foil and the third metal foil are simultaneously patterned by both-side simultaneous exposure.
8. The manufacturing method of a multilayer printed wiring board according to claim 1, further comprising: forming, in a second single-sided metal-foiled laminate sheet having a third insulating resin film and a fourth metal foil on a rear face of the third insulating resin film, a second adhesive protective layer having a second adhesive-agent layer that covers a front face of the third insulating resin film and a second protective film that is laminated on the adhesive-agent layer; forming a second bottomed via hole having a bottom face with the fourth metal foil exposed therefrom by partially removing the second adhesive protective layer and the third insulating resin film; filling a conductive paste into the second bottomed via hole by a printing method; and peeling off the second protective film from the second adhesive-agent layer and causing a part of the conductive paste filled in the second bottomed via hole to protrude from the second adhesive-agent layer, thereby obtaining a third wiring substrate, wherein in the laminating, the first to third wiring substrates are laminated in such a way that a protruding part of the conductive paste filled in the second bottomed via hole of the third wiring substrate comes into contact with a reception land that is formed by patterning the third metal foil of the second wiring substrate.
The present invention relates to a manufacturing method of a multilayer printed wiring board and the multilayer printed wiring board. More specifically, the present invention relates to a manufacturing method of a multilayer printed wiring board having three or more wiring layers that are interlayer connected through conductive vias formed of conductive paste and the multilayer printed wiring board.
Patent Literature 1: Japanese Patent No. 2631287 Patent Literature 2: Japanese Patent Laid-Open No. 2011-66293 Patent Literature 3: Japanese Patent Laid-Open No. 2007-96121
A manufacturing method of a multilayer printed wiring board according to an embodiment of the present invention includes
attaching an adhesive protective film having a weak adhesive layer formed on one side thereof to a single-sided metal-foiled laminate sheet having a first insulating resin film and a first metal foil on a front face of the first insulating resin film in such a way that the weak adhesive layer contacts with a rear face of the first insulating resin film,
forming a bottomed via hole that has a bottom face with the first metal foil exposed therefrom by partially removing the adhesive protective film and the first insulating resin film,
first printing of filling a conductive paste into the bottomed via hole by a printing method, peeling off the adhesive protective film from the first insulating resin film and causing a part of the conductive paste filled in the bottomed via hole to protrude from the first insulating resin film, and thereby obtaining a first wiring substrate,
forming, on a double-sided metal-foiled laminate sheet having a second insulating resin film and second and third metal foils respectively provided on a front face and a rear face of the second insulating resin film, a piercing mask by patterning the second metal foil,
forming an adhesive protective layer including an adhesive-agent layer that covers the front face of the second insulating resin film and buries the patterned second metal foil and a protective film that is laminated on the adhesive-agent layer,
forming a bottomed step via hole that has a middle part with the piercing mask exposed therefrom and a bottom face with the third metal foil exposed therefrom by partially removing the adhesive protective layer and the second insulating resin film,
second printing of filling a conductive paste into the bottomed step via hole by a printing method,
peeling off the protective film from the adhesive-agent layer and causing a part of the conductive paste filled in the bottomed step via hole to protrude from the adhesive-agent layer, thereby obtaining a second wiring substrate, and
laminating in which the first wiring substrate and the second wiring substrate are laminated in such a way that a protruding part of the conductive paste filled in the bottomed via hole of the first wiring substrate comes into contact with a protruding part of the conductive paste filled in the bottomed step via hole of the second wiring substrate, and the laminated first and second wiring substrates are heated to be integrated with each other.
FIG. 4 is a process sectional view for explaining a manufacturing method of a wiring substrate 40 of a multilayer printed wiring board 50 according to a second embodiment of the present invention.
FIG. 5B is a sectional view of the multilayer printed wiring board 50 according to the second embodiment of the present invention.
Subsequently, reception lands 2a and wirings 2b are formed by patterning the metal foil 2 by a known photofabrication method. The diameter of the reception land 2a is approximately .phi.250 .mu.m, for example.
Subsequently, the adhesive protective film 4 and the insulating resin film 1 are partially removed, thereby forming bottomed via holes (bottomed conducting holes) 5 each having a bottom face with the metal foil 2 exposed therefrom as illustrated in (4) of FIG. 1B. The diameter of the bottomed via hole 5 is .phi.150 to 200 .mu.m, for example.
Roughing treatment may be performed to the metal foil 12 before the adhesive protective layer 17 is formed. The roughing treatment can improve the adhesion strength between the metal foil 12 and the adhesive-agent layer 15. Here, the roughing treatment is performed to the copper foil that is the metal foil 12 using Neo Brown NBD series manufactured by Ebara-Udylite Co., Ltd.
In this process, in addition to the bottomed step via holes 18a, bottomed via holes 18b and 18d and bottomed step via holes 18c are formed as illustrated in (4) of FIG. 28. The bottomed via hole 18b is a bottomed via hole that penetrates the adhesive protective layer 17 in the thickness direction and has a bottom face with the reception land 12b exposed therefrom. The bottomed step via hole 18c is a bottomed step via hole having a same structure as the bottomed step via hole 18a. The bottomed via hole 18d is a bottomed via hole that penetrates the adhesive protective layer 17 and the insulating resin film 11 in the thickness direction and has a bottom face with the reception land 13a exposed therefrom.
Subsequently, conductive pastes 19 are filled into the bottomed step via holes 18a and 18c and the bottomed via holes 18b and 18d, by a printing method (a second printing process) as illustrated in (5) of FIG. 28. More specifically, while the protective film 16 is used as a printing mask, the conductive pastes 19 are filled into the bottomed step via holes 18a and 18c and the bottomed via holes 18b and 18d by a printing method such as screen printing. The conductive pastes 19 are obtained by dispersing metal particles on resin binder that is a pasty thermosetting resin.
The above processes provide the wring substrate 20 illustrated in (6) of FIG. 2B.
Subsequently, in the single-sided metal-foiled laminate sheet 23, reception lands 22a and wirings 22b are formed by patterning the metal foil 22 by a known photofabrication method. The diameter of the reception land 22a is approximately 0250 .mu.m, for example.
The conductive via 51 is formed of conductive via parts 51a, 51b, and 51c. The conductive via 52 is formed of conductive via parts 52a, 52b, and 52c. The conductive via 53 is formed of conductive via parts 53a, 53b, and 53c.
Subsequently, the adhesive protective film 35 is peeled off from the insulating resin film 11, thereby causing respective parts of the conductive pastes 19C to protrude from the piercing masks 12a as illustrated in (3) of FIG. 7. Similarly, the adhesive protective film 36 is peeled off from the insulating resin film 11, thereby causing respective parts of the conductive pastes 190 to protrude from the piercing masks 13c.
Subsequently, an adhesive protective layer 9B is formed on the front face 21a of the single-sided metal-foiled laminate sheet 23 as illustrated in (1) of FIG. 8. The adhesive protective layer 9B includes an adhesive-agent layer 7B that covers the front face 21a of the insulating resin film 21 and a protective film 83 that is laminated on the adhesive-agent layer 7B. The forming method of the adhesive protective layer 9B is identical to that of the adhesive protective layer 17 in the first embodiment, and therefore, explanations thereof are omitted.
1, 11, 21 INSULATING RESIN FILM 1a, 11a, 21a FRONT FACE 1b, 11b, 21b REAR FACE 2, 12, 13, 22 METAL FOIL 2a RECEPTION LAND 2b WIRING 3, 23 SINGLE-SIDED METAL-FOILED LAMINATE SHEET 4, 35, 36 ADHESIVE PROTECTIVE FILM 5, 18b, 18d, 27 BOTTOMED VIA HOLE 6, 6A, 19, 19A, 19B, 19C, 19D, 28, 28A CONDUCTIVE PASTE 6a, 19a, 28a PROTRUDING PART 7A, 7B, 15, 15A, 15B, 247 ADHESIVE-AGENT LAYER 8A, 8B, 16, 16A, 16B, 25 PROTECTIVE FILM 9A, 17, 17A, 17B, 26 ADHESIVE PROTECTIVE LAYER 10, 10A, 20, 20A, 40, 40A WIRING SUBSTRATE 12a, 13c PIERCING MASK 12b, 13a, 22a RECEPTION LAND 12c, 13b, 22b WIRING 14 DOUBLE-SIDED METAL-FOILED LAMINATE SHEET 18a, 18c BOTTOMED STEP VIA HOLE 30, 50, 60 MULTILAYER PRINTED WIRING BOARD 31, 32, 33, 34, 51, 52, 53, 61, 62, 63 CONDUCTIVE VIA 31a UPPER CONDUCTIVE VIA PART 31b LOWER CONDUCTIVE VIA PART 32a, 32b, 34a, 34b, 51a, 51b, 51c, 52a, 52b, 52c, 53a, 53b, 53c, 61a, 61b, 61c, 62a, 62b, 62c, 63a, 63b, 63c CONDUCTIVE VIA PART
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