Current transport in GaSb /GaInAsSb/GaAlAsSb heterojunction photodiodes

Current flow mechanisms have been studied for Liquid Phase Epitaxy (LPE) grown n-GaSb /n-GaInAsSb /p -GaAlAsSb heterostructures lattice-matched to GaSb substrates. An experimental investigation of current-voltage characteristics has been done in the temperature range from 80-300K, and have been determined the mechanism of the flow of dark current. The qualitative comparison of experimental results with theory shows that, in the high temperature region the diffusion mechanism of the current flow dominates in both, forward and reverse biases. The tunneling charge has the key role at low temperatures under both forward and reverse biases.