Etching a:CH films by electron cyclotron resonance microwave plasma

In order to obtain good etching effect, parameters as working pressure and ratio of gas flux for etching processes with and without Al mask were studied. The results are as follows: under the same conditions, etching rate varies little; whether or not having Al mask on a: CH films have no effect on etching rate; when gas flux is fixed, etching rate descends with bulk ratio of argon and oxygen increasing. In this study, the best etching conditions are using pure oxygen gas, flux of 4 mL·s-1, working pressure of 9.9×10-2 Pa, microwave current of 80 mA, bias of -90 V. Under these conditions, fabricated micro-gear has vertical sidewall, small degree of distortion. Micro-gear could be released from the substrate using HF solution.