Analysis of Leakage Currents in MOCVD Grown GalnAsSb Based Photodetectors Operating at 2 mu m

摘要

This paper reports the fabrication and characterization of GalnAsSb photodetectors operating at 2 mu m.At room temperature,the performance of these photodiodes under reverse bias conditions is limited by the surface leakage.A model has been developed to separate the bulk (diffusion and generation-recombination (g-r)) and the surface leakage contributions toward the total leakage current.By fitting this model to the experimental data,values of material parameters such as minority carrier diffusion length and lifetime have been estimated.The highest R_0A of 55 OMEGA-cm~2 has been obtained with a responsivity of 0.44 AAV at 2 mu m.