Passivation of InAs/GaInSb Superlattices for Improved VLWIR Focal Plane Performance

High performance InAsGaInSb superlattice detectors are of great interest to the DoD for various DoD applications and, in particular, detection of space borne objects. They are capable of infrared detection from 2 to >30 mm. This proposal will utilize anadvanced plasma deposition process to passivate surface traps, to dramatically reduce surface-related transient effects and improve the device performance. We will use this technique to produce high quality passivation layers, such that charge traps in thelayer can be greatly reduced which are a major source of leakage current. During the Phase I of the project this deposition method will be investigated for the oxy-nitride material. Detector devices with passivation layer will be fabricated and comparedwith untreated samples. This process will be further optimized in the follow-on Phase II leading to significant improvement in the detection capability of the superlattice devices. The proposed passivation technique is expected to be scalable forcommercial production and can be extended to a host of other device structures. This material system has detection capability from 2-30 um. Within the infrared range various products can be developed including thermal and medical imaging, and pollutionmonitoring.The passivatin process will improve overall detection performance.