Patent ID: 6083845
Filing Date: 2000-07-04
Classification: H01L

Abstract:
An etching method used in a high density plasma etching system to etch a silicon oxide dielectric layer for forming openings of different depth, comprising:performing a first stage of an etching process on the dielectric silicon oxide layer using a mixture of C.sub.4 H.sub.8, CH.sub.2 F.sub.2, and Ar as an etching gas source;performing a second stage of the etching process on the dielectric layer using a mixture of C.sub.4 H.sub.8, CO, and Ar as an etching gas source; andperforming a third stage of the etching process on the dielectric silicon oxide layer using a mixture of C.sub.4 H.sub.8, CH.sub.2 F.sub.2, CO, and Ar as an etching gas source.