Patent ID: 7598178

Claim:
A method of forming an epitaxial film on a substrate comprising: (a) providing a substrate; (b) exposing the substrate to a silicon source and at least one of SiH2(CH3)2, SiH(CH3)3, Si(CH3)4, 1,3-disilabutane, and C2H2, at a temperature of greater than about 250 degrees Celsius and a pressure greater than about 1 Torr so as to form an epitaxial film on at least a portion of the substrate; and (c) exposing the substrate to an etchant so as to etch the epitaxial film and any other films formed during step (b), the etchant comprising a compound from the group consisting of HCl and Cl2, and combinations thereof, wherein a larger flow rate of HCl relative to Cl2 is employed.