Selective Tungsten Nitride Formation
Original Publication Date: 1988-Jul-01
Included in the Prior Art Database: 2005-Feb-15
This article describes a technique utilizing ammonia to nitridize tungsten at low temperatures. Tungsten plays an important role in very large scale integration (VLSI) technology, as it has midgap gate work function (4.8 ev), and it has low resistivity for source-drain and gate metallization. However, it is very susceptive to formation of volatile oxides during deposition of any oxide passivating layers. This results in degradation of film qualities. Thus, there is a need to provide a selective protection for tungsten.