Hydrogenation of SLS for Defect Mitigation of III-V-based Infrared Detectors

Infrared devices fabricated using III-V strained-layer superlattice (SLS) materials have many advantages over present state-of-the-art HgCdTe detectors, e.g., cost, manufacturability, operability, and theoretically lower Auger generation rates. However, due to the presence of inherent growth related defects the SLS materials have not achieved full potential. While growth improvements are anticipated, it is not clear whether those will be sufficient enough to enable widespread adoption of the SLS technology. This issue is addressed by a post-epitaxy process for improving material quality by passivating defects and shallow donor impurities with a UV-assisted hydrogenation. This is ideally suited to advance the integration of SLS into DoD systems due to its effectiveness and the ease of its integration into the process flow. The primary parameter to monitor material quality is the minority carrier lifetime, which was nearly doubled by hydrogenation as demonstrated in the Phase I program. In this Phase II, in partnership with Hughes Research Laboratories and Air Force Research Laboratory we will optimize the hydrogenation process, evaluate lifetimes, and test Performance Evaluation Chips, and FPA operabilities of treated materials.