Development of High-Performance eSWIR HgCdTe-Based Focal-Plane Arrays on Silicon Substrates

摘要

We report the development of high-performance and low-cost extended short-wavelength infrared (eSWIR) focal-plane arrays (FPAs) fabricated from molecular beam epitaxial (MBE)-grown HgCdTe on Si-based substrates. High-quality n-type eSWIR HgCdTe (cutoff wavelength similar to 2.68 mu m at 77 K, electron carrier concentration 5.82 x 10(15) cm(-3)) layers were grown on CdTe/Si substrates by MBE. High degrees of uniformity in composition and thickness were demonstrated over three-inch areas, and low surface defect densities (voids 9.56 x 10(1) cm(-2), micro-defects 1.67 x 10(3) cm(-2)) were measured. This material was used to fabricate 320 x 256 format, 30 mu m pitch FPAs with a planar device architecture using arsenic implantation to achieve p-type doping. The dark current density of test devices showed good uniformity between 190 K and room temperature, and high-quality eSWIR imaging from hybridized FPAs was obtained with a median dark current density of 2.63 x 10(-7) A/cm(2) at 193 K with a standard deviation of 1.67 x 10(-7) A/cm(2).