Investigation of the surface morphology of P-doped LPCVD silicon films

The surface morphology of LPCVD silicon films as a function of P doping concentration has been investigated. The films were deposited in the amorphous phase at 550/spl deg/C and in the polycrystalline phase at 620/spl deg/C and were P doped at 1.5/spl times/10/sup 20/ cm/sup -3/, 1/spl times/10/sup 20/ cm/sup -3/ and 9/spl times/10/sup 19/ cm/sup -3/ concentrations. SEM and EDX observations showed that hillocks of pure silicon are formed on the film surface. Their size increases as the phosphorus concentration increases, the variations being more significant for the amorphous phase deposited films.