Influence of deposition conditions on mechanical properties of low-pressure chemical vapor deposited low-stress silicon nitride films

Low-pressure chemical vapor deposited silicon nitride films were deposited with room temperature deposition stresses. The effect of deposition pressure, input gas ratio, and deposition temperature was evaluated. Film biaxial modulus, hardness, thermal expansion, and plane strain modulus were independent of room temperature deposition stress. Film density and refractive index were sensitive to the changes in the deposition conditions and room temperature deposition stress was altered by the changes.