EP0478313A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A multilayer printed circuit board and manufacturing method therefor
Assignee: International Business Machines Corp
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Filing: 1991-09-25
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Granted: —
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Expires: 2011-09-25
Abstract
Abstract A laminate of wiring layers are stacked up on one side of a copper clad glass-epoxy substrate by alternately depositing photosensitive resin layers and electrolessly plated copper layers. The copper layer on the one side of the copper clad substrate is used as a first level wiring layer. Interconnection of the wiring layers are made by vias in the photosensitive resin layers. The copper layer on the other side of the substrate is used as a power plane. Interconnection between the power plane and power supply pads or lands in the outermost wiring layer is made by plated through holes which extend through the substrate. Thus the photoprocessed vias are used for interconnection of signal conductors in the wiring layers and the plated through holes are used for power connections. This minimizes the use of relatively large, mechanically drilled through holes to thereby provide higher circuit density. The laminate of the wiring layers may be provided on both sides of the substrate. In this modification, the copper layer on the other side of the copper clad substrate may be used as an additional wiring layer, not as a power plane, and the power conductors are formed in the outermost copper layers, which are interconnected by through holes.
Inventors
- 👤 Yutaka Tsukada
- 👤 Shuhei Tsuchida
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 17:49
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/4602; H05K1/00; H05K1/02; H05K1/0213; H05K1/0263; H05K1/0265; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0352; H05K2201/09; H05K2201/09209; H05K2201/0929; H05K2201/09327; H05K2201/095; H05K2201/09509; H05K2203/00; H05K2203/14; H05K2203/1438; H05K2203/15; H05K2203/1581; H05K3/0011; H05K3/0017; H05K3/0023; H05K3/10; H05K3/18; H05K3/181; H05K3/40; H05K3/42; H05K3/425; H05K3/426; H05K3/429; H05K3/4644; H05K3/4661; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49126; Y10T29/49155; Y10T29/49165
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
111 words
A multilayer printed circuit board comprising: an insulating substrate (10); a conductive layer (14) provided on one side of said substrate; a laminate provided on the other side of said substrate, said laminate comprising wiring layers (12,22,36) and at least one insulating layer (18); a conductive through hole (32) extending through said substrate (10) and said laminate; said conductive layer (14) including a power supply conductor (46); the outermost wiring layer (36) of said laminate including signal wiring conductors (40) and a power supply conductor (44); and the power supply conductors (46,44) in said conductive layer (14) and said outermost wiring layer (36) being interconnected by said conductive through hole (32).
Claim 2
Dependent Claim
81 words
A multilayer printed circuit board comprising: an insulating substrate (10); a laminate provided on each side of said substrate, each said laminate comprising wiring layers and at least one insulating layer; a conductive through hole (32) extending through said substrate and said laminates; the outermost wiring layer of each said laminate including signal wiring conductors (40,40′) and power supply conductors (44,46); and the power supply conductors in said outermost wiring layers of said laminates being interconnected by said conductive through hole.
Claim 3
Dependent Claim
44 words
A multilayer printed circuit board ms claimed in Claim 1 or Claim 2, wherein each of said wiring layers (12,22,36) includes signal wiring conductors (16,26,40) and said signal wiring conductors in said wiring layers are interconnected by conductive vias (24,34) in said insulating layers.
Claim 4
Dependent Claim
22 words
A multilayer printed circuit board as claimed in any preceding Claim wherein said insulating substrate (10) is a glass - epoxy substrate.
Claim 5
Dependent Claim
34 words
A multilayer printed circuit board as claimed in any preceding Claim, wherein said signal wiring conductors (40) in said outermost wiring layer (36) are patterned to provide terminals for attachment of surface mount components.
Claim 6
Dependent Claim
23 words
A multilayer printed circuit board as claimed in any preceding Claim, wherein said outermost wiring layer (36) further includes a ground conductor (42).
Claim 7
Independent Claim
258 words
A method for manufacturing a multilayer printed circuit board comprising the steps of: (a) preparing an insulating substrate (10) with both surfaces being clad with copper; (b) patterning the copper layer (12) on one side of said substrate to form a wiring layer including signal wiring conductors (16); (c) depositing an insulating layer (18) on said wiring layer; (d) forming vias (20) in said insulating layer (18) to expose selected portions of said signal wiring conductors (16); (e) depositing a copper layer (22) on said insulating layer, including said vias; (f) patterning the deposited copper layer (22) to form a wiring layer including signal wiring conductors (26); (g) repeating said steps (c) - (f), as required; (h) depositing an insulating layer (28) on the top wiring layer; (i) forming vias in the insulating layer (28) formed in step (h) to expose selected portions of the signal wiring conductors (26) in said top wiring layer; (j) forming a through hole (32) at a selected location of the resulting structure; (k) depositing a copper layer (36) on the entire surface of said structure, including said through hole (22); and (l) patterning the deposited copper layer (36) to form, on the insulating layer formed in step (h), an outermost wiring layer including signal wiring conductors (40) and a power supply conductor (44) and, on the other side of said substrate, a conductive layer (14) including a power supply conductor (46), said power supply conductors (44,46) in said outermost wiring layer and said conductive layer being interconnected by said through hole (32).
Claim 8
Independent Claim
237 words
A method for manufacturing a multilayer printed circuit board comprising the steps of: (a) preparing an insulating substrate (10) with both surfaces being clad with copper; (b) patterning the copper layers (12,14) on both sides of said substrate to form wiring layers including signal wiring conductors (16,16′); (c) depositing an insulating layer (18,18′) on each of said wiring layers; (d) forming vias (20,20′) in said insulating layers to expose selected portions of said signal wiring conductors in said wiring layers; (e) depositing a copper layer (22,22′) on each of said insulating layers, including said vias; (f) patterning the deposited copper layers (22,22′) to form wiring layers including signal wiring conductors (26,26′); (g) repeating said steps (c) - (f), as required; (h) depositing an insulating layer (28,28′) on each of the top wiring layers; (i) forming vias in the insulating layers formed in step (h) to expose selected portions of the signal wiring condurtors (26,26′) in said top wiring layers; (j) forming a through hole (32) at a selected location of the resulting structure; (k) depositing a copper layer (36,36′) on the entire surface of said structure, including said through hole (32); and (l) patterning the deposited copper layer (36) to form, on each side of said substrate, an outermost wiring layer including signal wiring conductors (40,40′) and power supply conductors (44,46), said power supply conductors in said outermost wiring layers being interconnected by said through hole (32).
Claim 9
Dependent Claim
33 words
A method as claimed in Claim 7 or Claim 8, wherein said insulating layers are formed out of a photosensitive resin and said vias are formed by exposing and developing the photosensitive layers.
Claim 10
Independent Claim
20 words
A method as claimed in any preceding Claim, wherein the deposition of said copper layers are performed by electroless plating.
Claim 11
Independent Claim
24 words
A method as claimed in any preceding Claim, wherein said outermost wiring layer is patterned to provide terminals for attachment of surface mount components.
Claim 12
Independent Claim
22 words
A method as claimed in any preceding Claim, wherein said outermost wiring layer is patterned to further include a ground conductor (42).
References Cited (Backward Citations)
No citation records indexed.
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