Electrical and photoelectrical properties of isotype N+-GaSb/n(0)-GaInAsSb/N+-GaAlAsSb double heterojunctions

Abstract

The electrical and optical properties of a double type II heterojunction in the GaSb/GaInAsSb/GaAlAsSb system with staggered band alignment were studied. The dark current mechanisms in the isotype heterostructures were investigated at several temperatures. It is shown that a type II staggered hetero-junction can behave as Schottky diodes and the dark current-voltage (I-V) characteristics of this isotype heterostructures were rectifying over the whole temperature range 90-300 K. The qualitative comparison of experimental results with theory shows that, the low temperature region the tunneling mechanism of the current flow dominates in both, forward and reverse biases. A mechanism of photocurrent amplification in isotype N+-n(0)-N+ heterojunctions due to hole confinement at the type II interface is observed and discussed.