Two step process for forming an oxide layer over a stepped surface of semiconductor wafer.

摘要

A two step process is disclosed for forming a silicon oxide layer (40,50) over a stepped surface of a semiconductor wafer (10) while inhibiting the formation of voids in the oxide layer which comprises depositing a layer (40) of an oxide of silicon over a stepped surface of the semiconductor wafer (10) in a CVD chamber by flowing into the chamber a gaseous mixture comprising a source of oxygen, a portion of which comprises O3, and tetraethylorthosilicate as the gaseous source of silicon while maintaining the pressure in the CVD chamber within a range of from about 250 Torr to about 760 Torr and then depositing a second layer (50) of oxide over the first layer (40) in a CVD chamber by flowing into the chamber a gaseous mixture comprising a source of oxygen, a portion of which comprises O3; and tetraethylorthosilicate as the gaseous source of silicon while maintaining the CVD chamber at a lower pressure than during the first deposition step.