ETCHING METHOD AND ETCHING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an etching method etc. having a quick etching rate and high mask selectivity. SOLUTION: The etching method etches a silicon substrate laid on a base mount in a treatment chamber. The etching method comprises an etching step for etching the silicon substrate by giving bias potential to the base mount while supplying etching gas to be made plasma in the treatment chamber; a first step for repeating alternately the etching step and a protective film formation step for forming a protective film on the silicon substrate while supplying a protective film formation gas to be made plasma in the treatment chamber; and a second step for etching the silicon substrate by giving bias potential to the base mount while supplying the etching gas and the protective film formation gas to be made plasma in a treatment chamber. The first step and the second step are performed alternately once or more. An etching shape of an inclination angleθcan be acquired in such a way that etching is advanced in the depthwise direction of a groove as shown in Fig. 3 (a) in the first process, and also in the widthwise direction of the groove as shown in Fig. 3 (b) in the second step. COPYRIGHT: (C)2007,JPO&INPIT