| 摘要 |
PROBLEM TO BE SOLVED: To form a metal pattern or a circuit board having a high aspect ratio by being subjected to a multistage etching by means of a metal masking. SOLUTION: A resist (12) is applied to both the sides or one side of a copper sheet (10), the resist is patterned to form a resist pattern, a tinned layer (14) is formed by utilizing the resist pattern, the copper board is half-etched with the tinned layer as the masking, a positive resist (18) is applied, exposured and developed to protect a lower positive resist of the tinned layer, and the copper board is half-etched again with each tinned layer and protective resist layer as the masking. Such process is repeated, and, finally, the resist and the tinned layer used as the masking are removed to obtain the objective metal pattern. COPYRIGHT: (C)2007,JPO&INPIT |
