Determination of the doping profile near the metal-semiconductor interface of ZrN/GaAs contacts

摘要

The reduced capacitance and increased barrier heights observed for ZrN Schottky contacts to n-GaAs annealed from 700 to 850 degrees C suggest the progressive formation of a metal-p/sup +/-n diode. Since the position of the potential maximum varies with the applied voltage, the effective active profile of the p/sup +/ region can be determined by combining capacitance-voltage and current-density-voltage measurements. The analysis assumes only that the depletion approximation holds and the current is dominated by thermionic emission. When this analysis was applied to ZrN/GaAs Schottky contacts, it was found that the p/sup +/ region had penetrated more deeply into the n-type substrate as the annealing temperature was increased, consistent with the formulation of a metal-p/sup +/-n diode.