摘要 |
An etching process includes the steps of: preparing an etchant containing ferric chloride and an anticorrosive agent for Cu, and etching with said etchant a multi-layer metal structure including a Cu layer and an Ni layer. The etchant may preferably further contain ferrous chloride. The etching process is effective in making etching rates of the respective substantially equal, thus suppressing occurrence of burr portions of the Ni layers.
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