Control of sidewall angles using UV LEDs during wet etching of GaAs

Abstract

The ultraviolet (UV) light induced wet etching for micro-optical electromechanical systems applications produces a range of sidewall angles depending on the relative contributions of photo and chemical dissolution. The technique uses recently developed multi-element UV light emitting diodes (LEDs) that feature broad area coverage and relatively low cost compared with laser-based systems. The UV LED illumination creates sidewall profiles with angles ranging from 55° to 90° by changing the oxidizer content and the light intensity. © 2004 The Electrochemical Society. All rights reserved.