Patent ID: 6339023
Filing Date: 2002-01-15
Classification: C23C,H01L

Abstract:
A method of forming a blanket tungsten film on a substrate by chemical vapor deposition process, said method including:a first step of evacuating a vacuum chamber containing a substrate to a predetermined degree of vacuum; a second step of carrying out preprocessing of said substrate by introducing a first mixed gas containing tungsten hexafluoride gas and monosilane gas with a tungsten hexafluoride gas/monosilane gas flow ratio adjusted to less than 1 into said vacuum chamber for a processing time within the range of 2 to 10 seconds; a third step of forming a nucleus of a blanket tungsten film on said substrate by introducing a second mixed gas containing tungsten hexafluoride gas and monosilane gas with a tungsten hexafluoride gas/monosilane gas flow ratio adjusted to 1 or more into said vacuum chamber after completion of said second step; and a fourth step of growing a tungsten film on said substrate formed with said nucleus by introducing a third mixed gas containing tungsten hexafluoride gas and hydrogen gas at a predetermined ratio after completion of said third step.