A bias voltage dependence of trapped hole annealing and its measurement technique [MOS capacitor]

A bias voltage dependence of the trapped hole annealing was observed by using a unique irradiation technique with a MOS capacitor which exhibits almost no annealing of the trapped holes under negative bias. The result showed the change of time scale for the annealing behavior with the Boltzmann factor as a function of the surface potential of the substrate. This result suggests that the oxide of the MOS capacitor has a trap level positioned above the Si conduction band edge. Additional annealing experiments at several temperatures supported the results, and the position of the trap level was determined