Method of chemical vapor depositing tungsten films

摘要

A method of depositing tungsten on a semiconductor substrate is disclosed. The semiconductor substrate is heated to between about 360 DEG C and about 390 DEG C and preferably about 375 DEG C. Initiation gases are introduced into a first deposition station of a chemical vapor deposition chamber to form an amorphous, monolayer of silicon. Initiation gas comprises a silane gas flow at a rate of about 40 to about 48 standard cubic centimeters per minute. A nucleation gas flow rate formed of silane of about 20 to about 30 standard cubic centimeters per minute and a tungsten hexafluoride gas flow at a rate of about 300 to about 350 standard cubic standard centimeters per minute is next introduced. A hydrogen reducing gas flow rate is then introduced to form a layer of hydrogen reduced bulk tungsten. This reduced gas flow comprises a hydrogen gas flow at a rate of about 7,000 to about 8,500 standard cubic centimeters per minute gas flow, and a tungsten hexafluoride gas flow at a rate of about 300 to about 350 standard cubic centimeters per minute. A bulk hydrogen reduced tungsten is deposited at successive deposition stations.