Reactive ion etching of porous silicon for MEMS applications

Abstract

Dry etching by inductively-coupled-plasma reactive-ion etching was performed on porous silicon. When etching with a gas mixture of CF4 and O2, the etch rates of passivated PS were higher than that of Si by a factor of up to 20. It is found that the etch rate of PS is affected by the several seconds of plasma initialisation and stabilisation time.