Characterization of HOT MWIR InAs/InAsSb T2SL Discrete Photodetectors

A comprehensive study of mid-wavelength infrared (MWIR) InAs/InAsSb type-II superlattice (T2SL) photodetectors was performed for full characterization of the E-O performance, reliability, and linearity as well as response speed. Teledyne Judson Technologies has recently developed high operating temperature (HOT) MWIR InAs/InAsSb T2SL large area discrete detectors of 0.25mm and 1mm for front-side illumination. The 50% cut-off wavelength of the detectors ranges from similar to 5.4 to similar to 5.7 mu m at room temperature. For the reliability tests, the T2SL detectors were thermally cycled and humidity tested. Initial testing data showed excellent stability to the temperature and humidity, indicating the T2SL detectors have long-term stability. Linearity, response speed and capacitance were measured at various temperatures and reverse biases. This work presents comprehensive test results, data analysis, and discussion, showing these large size, discrete T2SL detectors have the potential to replace conventional MWIR detector materials.