PLASMA ETCHING METHOD, PLASMA ETCHING APPARATUS, CONTROL PROGRAM AND COMPUTER-READABLE STORAGE MEDIUM

摘要

A plasma etching method for performing an etching process for forming on an insulating film formed on a substrate a hole shape having a ratio of depth to opening width of more than 20. The hole shape is formed on the insulating film by converting processing gas containing at least C4F6 gas and C6F6 gas into a plasma. A flow rate ratio of the C4F6 gas to the C6F6 gas (C4F6 gas flow rate/C6F6 gas flow rate) ranges from 2 to 11.