Charge density dependence of photoinduced stress in semiconductors

An extension of a theory of photoinduced stress ill unipolar semiconductor is considered. To derive a relationship between the magnitude of photoinduced stress and carrier number densities correctly, electrons are clearly distinguished from holes in free carriers. The obtained correction term of photoinduced stress to the existing formula is proportional to electric charge density inside the semiconductor, and its coefficient is determined from the pressure coefficient of the valence band of the semiconductor. Using a corrected formula, numerical calculations of optical deformation for Si, Ge. and GaAs wafers are demonstrated.