Selective Tungsten Silicide Deposition
Original Publication Date: 1986-Oct-01
Included in the Prior Art Database: 2005-Mar-09
This article relates generally to thin film deposition and, more particularly, to selective deposition of tungsten silicide by chemical vapor deposition and plasma etching. Refractory tungsten silicide can be selectively deposited by steps of chemical vapor deposition and plasma etching. This technique avoids the necessity of forming and removing a protective pattern to define deposition areas and is compatible with either CMOS or NMOS processing. Tungsten silicide is deposited generally over a substrate having surface areas of both polysilicon and silicon dioxide by using the reaction of silane and tungsten hexafluoride. The nucleation rate is slower on the silicon dioxide surface than on the polysilicon. Flow conditions can be adjusted to maximize this difference.