Modeling the capacitance-voltage response of In0.53Ga0.47As metal-oxide-semiconductor structures: Charge quantization and nonparabolic corrections

The capacitance-voltage (C-V) characteristic is calculated for p-type In0.53Ga0.47As metal-oxide-semiconductor (MOS) structures based on a self-consistent Poisson-Schroumldinger solution. For strong inversion, charge quantization leads to occupation of the satellite valleys which appears as a sharp increase in the capacitance toward the oxide capacitance. The results indicate that the charge quantization, even in the absence of interface defects (D-it), is a contributing factor to the experimental observation of an almost symmetric C-V response for In0.53Ga0.47As MOS structures. In addition, nonparabolic corrections are shown to enhance the depopulation of the Gamma valley, shifting the capacitance increase to lower inversion charge densities. (C) 2010 American Institute of Physics. (doi:10.1063/1.3436645