Method of forming circuit wiring pattern

• US 5,369,881 A
• Filed: 09/20/1993
• Issued: 12/06/1994
• Est. Priority Date: 09/25/1992
• Status: Expired due to Term

• Current Assignee: Nippon Mektron Limited (NOK Corporation)
• Original Assignee: Nippon Mektron Limited (NOK Corporation)
• Inventors: Fujita, Norimasa, Inaba, Masaichi
• Primary Examiner(s): Arbes, Carl J.
• Application Number:
  US08/124,268
• Time in Patent Office: 442 Days
• Field of Search: 29/896, 228/180, 174/259, 174/262, 156/901, 156/902
• US Class Current: 29/846
• CPC Class Codes: H05K 2201/0347 Overplating, e.g. for reinforcing conductors or bumps; Plating over filled vias
• CPC Class Codes: H05K 2201/0376 Flush conductors, i.e. flush with the surface of the printed circuit
• CPC Class Codes: H05K 2201/09036 Recesses or grooves in insulating substrate
• CPC Class Codes: H05K 2201/09881 Coating only between conductors, i.e. flush with the conductors
• CPC Class Codes: H05K 2203/0152 Temporary metallic carrier, e.g. for transferring material
• CPC Class Codes: H05K 2203/025 Abrading, e.g. grinding or sand blasting
• CPC Class Codes: H05K 2203/0376 Etching temporary metallic carrier substrate
• CPC Class Codes: H05K 2203/0554 Metal used as mask for etching vias, e.g. by laser ablation
• CPC Class Codes: H05K 2203/0726 Electroforming, i.e. electroplating on a metallic carrier thereby forming a self-supporting structure
• CPC Class Codes: H05K 3/0023 by exposure and development of a photosensitive insulating layer
• CPC Class Codes: H05K 3/0032 of organic insulating material
• CPC Class Codes: H05K 3/045 by making a conductive layer having a relief pattern, followed by abrading of the raised portions
• CPC Class Codes: H05K 3/064 Photoresists
• CPC Class Codes: H05K 3/107 by filling grooves in the support with conductive material H05K3/045, H05K3/101, H05K3/1258 and H05K3/465 take precedence
• CPC Class Codes: H05K 3/108 by semi-additive methods; masks therefor characterised by metallic etch mask H05K3/062; electroplating methods or apparatus H05K3/241
• CPC Class Codes: H05K 3/205 using a pattern electroplated or electroformed on a metallic carrier
• CPC Class Codes: H05K 3/28 Applying non-metallic protective coatings H05K3/0091 takes precedence; methods for intermediate insulating layers for build-up multilayer circuits H05K3/4673
• CPC Class Codes: H05K 3/388 by the use of a metallic or inorganic thin film adhesion layer
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base

Abstract

This invention provides a method of forming a circuit wiring pattern which cannot be formed by a prior art method such as etching or plating. This method comprises a step of forming trenches for forming a circuit wiring pattern at predetermined positions on at least one of the surface of an insulating base material and then filling a conductive material into the trenches, a step of removing conductor layers in such a manner that the conductor layers formed by the step described above exist only in the trenches formed in the insulating base material and gap portions of the circuit wiring pattern comprising the conductor layers formed in the trenches of the insulating base material are exposed, and a step of forming an insulating surface protection layer.

Claims

1. A method of forming a circuit wiring pattern comprising the steps of:

forming trenches at predetermined positions for defining a circuit wiring pattern, on at least one of the surfaces of an insulating base material, and filling said trenches with a conductive material;

removing said conductive material in such a manner that a conductive layer resulting from said filling exists only in registration with said trenches formed in said insulating base material, and non-conductive gap portions of said circuit wiring pattern comprising said insulating base material intermediate said trenches are exposed; and

forming an insulating surface protection layer over the surface of said circuit wiring pattern.

2. A method of forming a circuit wiring pattern according to claim 1 wherein said trenches are so formed as to penetrate through said insulating base material from the other surface and wherein the step of filling the trenches with conductive material includes forming a conductive layer on said one surface of said insulating base material, the method further including the step of removing said conductive layer from said one surface of said insulating base material after formation of the circuit wiring pattern.

3. A method of forming a circuit wiring pattern according to claim 2 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises cutting and polishing from the side of said conductive layer.

4. A method of forming a circuit wiring pattern according to claim 2 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises selectively removing exposed metallic material after a resist layer is formed in desired regions.

5. A method of forming a circuit wiring pattern according to claim 1 wherein said trenches are formed by molding and machining.

6. A method of forming a circuit wiring pattern according to claim 1 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises cutting and polishing from the side of said conductive layer.

7. A method of forming a circuit wiring pattern according to claim 1 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises selectively removing exposed metallic material after a resist layer is formed in desired regions.

8. A method of forming a circuit wiring pattern comprising the steps of:

forming trenches at predetermined positions for defining a circuit wiring pattern on at least one of the surfaces of an insulating base material, and forming a functional film on the surface of said insulating base material including the surfaces of said trenches;

filling said trenches with conductive material;

removing said conductive material and functional film in such a manner that layers of said conductive material and said functional film remain in said trenches formed in said insulating base material, and non-conductive gap portions of said circuit wiring pattern are exposed intermediate said trenches; and

forming an insulating surface protection layer over the surface of said circuit wiring pattern defined by said conductive material in said trenches and said gap portions.

9. A method of forming a circuit wiring pattern according to claim 8 wherein said conductor layer is formed on one of the surface of said insulating base material and said trenches are so formed as to penetrate through said insulating base material from the other surface and which wherein the step of filling the trenches with conductive material includes forming a conductive layer on said one surface of said insulating base material, the method further including the step of removing said conductive layer from said one surface of said insulating base material after formation of the circuit wiring pattern.

10. A method of forming a circuit wiring pattern according to claim 9 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises cutting and polishing from the side of said conductive layer.

11. A method of forming a circuit wiring pattern according to claim 8 wherein said trenches are formed by molding and machining.

12. A method of forming a circuit wiring pattern according to claim 9 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises selectively removing exposed metallic material after a resist layer is formed in desired regions.

13. A method of forming a circuit wiring pattern according to claim 8 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises cutting and polishing from the side of said conductive layer.

14. A method of forming a circuit wiring pattern according to claim 8 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises selectively removing exposed metallic material after a resist layer is formed in desired regions.

15. A method of forming a circuit wiring pattern comprising the steps of:

forming trenches at predetermined positions for defining a circuit wiring pattern on at least one of the surfaces of an insulating base material, and then forming a layer of conductive material on the surface of said insulating base material, said layer of conductive material extending into and filling said trenches;

removing said conductive material in such a manner that said conductive layer exists only in said trenches formed in said insulating base material and said insulating base material is exposed in regions displaced from said trenches; and

forming an insulating surface protection layer over said remaining conductive layer.

16. A method of forming a circuit wiring pattern according to claim 15 wherein said conductor layer is formed on one of the surface of said insulating base material and said trenches are so formed as to penetrate through said insulating base material from the other surface and which wherein the steer of filling the trenches with conductive material includes forming a conductive layer on said one surface of said insulating base material, the method further including the step of removing said conductive layer from said one surface of said insulating base material after formation of the circuit wiring pattern.

17. A method of forming a circuit wiring pattern according to claim 16 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises cutting and polishing from the side of said conductive layer.

18. A method of forming a circuit wiring pattern according to claim 16 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises selectively removing exposed metallic material after a resist layer is formed in desired regions.

19. A method of forming a circuit wiring pattern according to claim 15 wherein said trenches are formed by molding and machining.

20. A method of forming a circuit wiring pattern according to claim 15 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises cutting and polishing from the side of said conductive layer.

21. A method of forming a circuit wiring pattern according to claim 15 wherein said step of removing conductive material to expose said insulating base material layer in pattern gaps comprises selectively removing exposed metallic material after a resist layer is formed in desired regions.