High Responsivity InGaAsSb P–n Photodetector for Extended SWIR Detection

A molecular beam epitaxy-grown InGaAsSb p–n photodetector lattice matched to GaSb for extended short wave infrared is reported. Electrical and optical characteristics were analyzed at temperatures from 200 K to room temperature. The photodetectors exhibit dark current densities of 2.9 × 10−6 A/cm2 at 200 K and 4.6 mA/cm2 at 300 K (−0.1 V bias) and a high quantum efficiency of 73% at room temperature under front side illumination. High detectivity (D*) values of 2.2 × 1010 cm·Hz1/2 W−1 and 7.4 × 1011 cm·Hz1/2 W−1 were observed at 200 K and room temperature, respectively.