Engineering the interface chemistry for improved performance III-V based infrared sensors

The unique electronic properties of Ga-free InAs/InAsSb type-II superlattices (T2SL) make them a superior alternative to the conventional HgCdTe sensors for the detection of Infrared Spectrum. Despite the highly promising performance of the T2SL device architectures with barriers, the p-type absorbers are very sensitive to surface band bending resulting in high leakage current. During the Phase I efforts, RMD will address this challenge by demonstrating a suitable passivation on p-type T2SL test structures by engineering the interface chemistry in order to eliminate the surface states. The Phase II effort will further this research by evaluating the FPA’s long term performance reliability by adopting the proposed passivation technology. The proposed passivation strategy is anticipated to provide chemical, electrical and gas diffusion barriers to the T2SL mesa surfaces. The process developed here will be amenable for commercial scale up and can be integrated with the traditional IRFPA manufacturing.