High frequency signal transmission structure and method for same

Abstract

A high frequency signal transmission structure includes an insulating sheet and a conductive wiring layer forming on the insulating sheet. The conductive wiring layer includes a silver conductive layer forming on the insulating sheet, a copper conductive layer forming on the silver conductive layer, and a silver covering layer covering a top surface and side surfaces of the copper conductive layer. The silver conductive layer and the silver covering layer together surround the copper conductive layer.

What is claimed is: 
     
         1 . A method for manufacturing a high frequency signal transmission structure, comprising:
 providing an insulating sheet, evaporating a silver bottom layer on the insulating sheet;   forming a copper conductive layer on part of the silver bottom layer;   removing the silver bottom layer which exposed by the copper conductive layer; and   forming a silver covering layer on the copper conductive layer, and the copper conductive layer is surrounded by the silver bottom layer and the silver covering layer, and the silver bottom layer, the copper conductive layer and the silver covering layer together form a conductive wiring layer.   
     
     
         2 . The method of  claim 1 , wherein the insulating sheet is made from polyester polymer. 
     
     
         3 . The method of  claim 1 , wherein before the step of evaporating a silver bottom layer on the insulating sheet, further comprising a step of pre-treatment to the surface of the insulating sheet. 
     
     
         4 . The method of  claim 3 , wherein a method of the pre-treatment comprising: and the ester group comprised in the insulating sheet is first hydrolyzed into carboxyl, the carboxyl (—COOH) then changed into ester ions (—COO − ) in a slightly alkaline environment. 
     
     
         5 . The method of  claim 2 , wherein a method for forming the copper conductive layer comprising:
 forming a dry film on the silver bottom layer;   exposing and development the dry film to deform a pattern of the copper conductive layer;   electroplating a copper layer on the silver bottom layer to form the copper conductive layer, and removing the dry film.   
     
     
         6 . The method of  claim 1 , wherein the silver bottom layer of exposed by the copper conductive layer is removed by an etching method using an alkaline solution. 
     
     
         7 . The method of  claim 1 , wherein a thickness of the silver conductive layer is same with a thickness of the silver covering layer. 
     
     
         8 . A high frequency signal transmission structure comprising:
 an insulating sheet, and   a conductive wiring layer forming on the insulating layer comprising:
 a silver conductive layer forming on the insulating sheet, 
 a copper conductive layer forming on the silver conductive layer, and a silver covering layer covering a top surface and side surfaces of the copper conductive layer, the silver conductive layer and the silver covering layer together surround the copper conductive layer. 
   
     
     
         9 . The high frequency signal transmission structure of  claim 8 , wherein a thickness of the silver conductive layer is about 0.1˜2 μm. 
     
     
         10 . The high frequency signal transmission structure of  claim 8 , wherein the insulating sheet is made from polyester polymer. 
     
     
         11 . The high frequency signal transmission structure of  claim 8 , wherein the silver conductive layer is formed on the insulating sheet using vapor deposition method. 
     
     
         12 . The high frequency signal transmission structure of  claim 8 , wherein a thickness of the silver conductive layer is same with a thickness of the silver covering layer. 
     
     
         13 . A method for manufacturing a high frequency signal transmission structure, comprising:
 providing an insulating sheet, forming a silver bottom layer on the insulating sheet;   forming a copper conductive layer on a surface of the silver bottom layer;   removing the silver bottom layer which exposed by the copper conductive layer; and   forming a silver covering layer on the copper conductive layer, and the copper conductive layer is surrounded by the silver bottom layer and the silver covering layer, and the silver bottom layer, the copper conductive layer and the silver covering layer together form a conductive wiring layer.   
     
     
         14 . The method of  claim 13 , wherein the insulating sheet is made from polyester polymer. 
     
     
         15 . The method of  claim 13 , wherein before the step of evaporating a silver bottom layer on the insulating sheet, further comprising a step of pre-treatment to the surface of the insulating sheet. 
     
     
         16 . The method of  claim 13 , wherein a method of the pre-treatment comprising: and the ester group comprised in the insulating sheet is first hydrolyzed into carboxyl, the carboxyl (—COOH) then changed into ester ions (—COO − ) in a slightly alkaline environment. 
     
     
         17 . The method of  claim 13 , wherein a method for forming the copper conductive layer comprising:
 forming a dry film on the silver bottom layer;   exposing and development the dry film to deform a pattern of the copper conductive layer;   electroplating a copper layer on the silver bottom layer to form the copper conductive layer, and removing the dry film.   
     
     
         18 . The method of  claim 13 , wherein the silver bottom layer of exposed by the copper conductive layer is removed by an etching method using an alkaline solution. 
     
     
         19 . The high frequency signal transmission structure of  claim 13 , wherein the silver conductive layer is formed on the insulating sheet using vapor deposition method.