High quantum efficiency Schottky diode photodetector on the base of ultrathin GaAs-on-Si film

Abstract

A new type of a Schottky diode photodetector based on the ultrathin (10 nm) low-temperature grown GaAs-on-Si heterolayer was fabricated and studied. Properties of the heterostructure and electrical characteristics of the photodetector were determined using low-temperature photoluminescence, high-resolution transmission electron microscopy, capacitance-voltage, current-voltage, and spectral responsivity measurements. The high responsivity of the photodetector (corresponding to external quantum efficiency of 0.8-0.9) is explained by effective carriers separation in the GaAs layer and by the carrier multiplication effect at the GaAs/Si interface. © 1996 American Institute of Physics.