Characterization and impact of traps in lattice-matched and strain-compensated In1−xGaxAs/GaAs1−ySby multiple quantum well photodiodes

Abstract

InP-based multiple quantum well (MQW) photodiodes in the InGaAs/GaAsSb material system are promising for mid-infrared detection [1]; by including strain in these devices, the detection wavelength has been extended to beyond 3 μm [2]. However, owing to the relative immaturity of these materials, there have been few reports of the characteristics of defects in this system and their impact on device performance, especially under strain and at material compositions appropriate for MQW detectors. In this work, In0.53Ga0.47As/GaAs0.5Sb0.5 (lattice-matched) and In0.34Ga0.66As/GaAs0.25Sb0.75 (strain-compensated) MQW photodiodes are evaluated using low-frequency noise spectroscopy (LFNS) and deep level transient spectroscopy (DLTS) to detect and extract the properties of defect levels, and their impact on dark current and noise performance of the photodiodes is evaluated.