Shield Film, Shielded Printed Wiring Board, And Method for Manufacturing Shield Film

• US 20140326484A1
• Filed: 10/12/2012
• Published: 11/06/2014
• Est. Priority Date: 11/24/2011
• Status: Active Grant

• Current Assignee: Tatsuta Electric Wire & Cable Co Ltd
• Original Assignee: Tatsuta Electric Wire & Cable Co Ltd
• Inventors: Tajima, Hiroshi, Yamauchi, Sirou, Kamino, Kenji, Watanabe, Masahiro
• Granted Patent: US 10,015,915 B2
• Time in Patent Office: Days
• US Class Current: 174/250
• CPC Class Codes: H05K 1/0216 Reduction of cross-talk, noise or electromagnetic interference grounding H05K1/0215
• CPC Class Codes: H05K 2201/0715 provided by an outer layer of PCB
• 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 9/00 Screening of apparatus or components against electric or magnetic fields devices for absorbing radiation from an antenna H01Q17/00
• CPC Class Codes: H05K 9/0084 comprising a single continuous metallic layer on an electrically insulating supporting structure, e.g. metal foil, film, plating coating, electro-deposition, vapour-deposition
• CPC Class Codes: H05K 9/0088 comprising a plurality of shielding layers; combining different shielding material structure
• CPC Class Codes: Y10T 29/49226 Electret making

Abstract

To provide a shield film which is capable of suitably shielding electric field waves, magnetic field waves, and electromagnetic waves progressing from one side to the other side of the shield film and has good transmission characteristics, a shielded printed wiring board, and a method for manufacturing the shield film, a metal layer 3 which is 0.5 μm to 12 μm thick and an anisotropic conductive adhesive layer 4 which is anisotropic so as to be electrically conductive only in thickness directions are provided in a deposited manner, so that electric field waves, magnetic field waves, and electromagnetic waves progressing from one side to the other side of the shield film are suitably shielded.

Claims

1. A shield film, comprising:

a metal layer which is 0.5 nm to 12 nm thick and an anisotropic conductive adhesive layer, which are in a deposited state.

2. The shield film according to claim 1, wherein the metal layer is metal foil.

3. The shield film according to claim 2, wherein the metal foil has been formed by rolling.

4. The shield film according to claim 3, wherein the thickness of the metal foil has been adjusted by etching.

5. The shield film according to claim 4, wherein the metal foil is mainly made of copper.

6. The shield film according to claim 5, wherein a protective metal layer is provided between the metal layer and the anisotropic conductive adhesive layer.

7. The shield film according to claim 1, wherein the metal layer has been formed by an additive process.

8. The shield film according to claim 7, wherein as the additive process, the metal layer has been formed by at least one of electroplating and electrodeless plating.

9. The shield film according to claim 1, wherein the shield film is configured to function as an electromagnetic waves shield film of a signal transmission system transmitting a signal with a frequency of 10 MHz to 10 GHz.

10. A shielded printed wiring board, comprising:

a printed wiring board including a base member in which a printed circuit is formed and an insulating film provided on the base member so as to cover the printed circuit; and

a shield film according to claim 1 provided on the printed wiring board.

11. The shielded printed wiring board according to claim 10, wherein the printed circuit includes a ground wiring pattern.

12. A method for manufacturing shield film, comprising the steps of:

forming metal foil with a predetermined thickness by rolling, then etching the metal foil to have a predetermined thickness falling within the range of 0.5 μ

m to 12 μ

m; and

forming an anisotropic conductive adhesive layer on one side of the metal layer.