Current pulses and high-frequency oscillations in a-Si/Si(p)/Si(n) heteroiunction device

摘要

A three-terminal a-Si/Si(p)/Si(n) heterojunction device was found to generate pulses of the collector current with a rise time of approximately 10~(-7) s and a fall time of approximately 4 × 10~(-7) s. The voltage applied to the base (0.8-1.5 V) controlled the pulse repetition rate. When the voltage reaches ～1.0 V, the pulses start to overlap, and the output signal is a high-frequency oscillation (10~6-10~7 Hz) of the collector current. A simple mechanism explaining the pulse generation and the high-frequency oscillations has been proposed. It involves the extremely high recombination rate of the injected carriers in the thin a-Si layer of the a-Si/Si(p) interface.