Two step thermal treatment procedure applied to polycide structures deposited using dichlorosilane as a reactant

摘要

A process for fabricating a polycide SAC structure, for a MOSFET device, has been developed. This process features a polycide SAC structure, comprised of tungsten silicide on in situ doped polysilicon, using tungsten hexafluoride and dichlorosilane as reactants for deposition of tungsten silicide. A first thermal anneal treatment is performed prior to polycide patterning, supplying protection to exposed tungsten silicide sides, during the patterning procedure. A second thermal anneal treatment is performed after polycide patterning, and prior to a silicon oxide deposition, offering protection to the exposed top surface of tungsten silicide, during the silicon oxide deposition.