High aspect ratio fabrication method using O2 RIE and electroplating

Abstract

A polyimide-based process for the fabrication of vertical structures with high aspect ratio has been developed. O2 reactive ion etching (O2 RIE) has been employed in the polyimide processing. Achieved etching characteristics of the O2 RIE system are: 4.0 μm/min etching rate, 15 aspect ratio, 75 μm etching depth. Polyimide has excellent chemical and thermal properties which makes it a good building material for micromachines. Polyimide could be also used as molds for electroplating. Electroplated copper structures were formed in the polyimide molds and metal gears were fabricated by these fabrication technologies. New possibilities for micromachining were opened by the use of O2 RIE and electroplating.