OPTICALLY STIMULATED DEEP-LEVEL IMPEDANCE SPECTROSCOPY - APPLICATION TO AN N-GAAS SCHOTTKY DIODE

Optically stimulated deep-level impedance spectroscopy is shown to be sensitive to transitions between deep-level states in an n-GaAs Schott ky diode. The technique is based on interpretation of both the real an d imaginary components of the impedance response over a continuous ran ge of electrical frequencies under sub-bandgap illumination. The resul ts obtained are compared to those by deep-level transient spectroscopy and thermally stimulated deep-level impedance spectroscopy. Optical e nergies associated with onset of electronic transitions are easily ide ntified at low electrical frequencies and from regression to the resul ting spectra of a model that accounts for the influence of deep-level states.