Fabrication of Au Microstructure Using ICP-RIE

UV lithography has been used in most case of microstructure patterning. However, it is difficult to form a fine rectangular microstructure in the thin film at a small width. On the other hand, silicon dry etching technology makes it possible to fabricate rectangular structures by repeating two steps of etching process and protection process. Then, we introduce the ability of Si dry etching technology in order fabricate un-tapered, high precision Au microstructures containing rectangular patterns in order to fabricate Au microstructures. Au electroforming was realized from the bottom of the Si microstructure groove. We succeeded in forming about 4 μm thick, void-free Au film in a space as narrow as 2.6 μm in large effective area of 60 mm squares on 4 inch Si wafer. Therefore, it is expected to be used in the production of a wide variety of devices that have not yer been put into practice.