Lam Research Corporation
SELF-LIMITING GROWTH

Abstract:

Provided herein are methods and apparatuses for forming metal films such as tungsten (W) and molybdenum (Mo) films on semiconductor substrates. The methods involve forming a reducing agent layer, then exposing the reducing agent layer to a metal precursor to convert the reducing agent layer to a layer of the metal. In some embodiments, the reducing agent layer is a silicon- (Si-) and boron- (B-) containing layer. The methods may involve forming the reducing agent layer at a first substrate temperature, raising the substrate temperature to a second substrate temperature, and then exposing the reducing agent layer to the metal precursor at the second substrate temperature. The methods may be used to form fluorine-free tungsten or molybdenum films in certain embodiments. Apparatuses to perform the methods are also provided.