SWIR HgCdTe 256x256 Focal Plane Array technology at BAE systems

This paper reports new performance data for SWIR HgCdTe 256x256 hybrid Focal Plane Arrays with cutoff wavelenaths of 2.6-2.7 mu m, operating at temperatures of 190 K to 220 K. The unit cell C, size is 30x30 mu m2. Back-illuminated SWIR HgCdTe P-on-n photodiode arrays were fabricated from two-layer LPE films grown on CdZnTe substrates. Response uniformity is excellent, with (sigma/mu=34%, and response operabilities are better than 99.9%. At a temperature of 190 K and a background photon flux of 6.8x10(11) ph/cm(2)-s, the median NEI is 1.1x10(9) ph/cm(2)-S, which is 1.4 times the BLIP NEI. NEI operabilities are better than 98.8%. Quantum efficiencies for large-area test diodes are 69% to 78%, close to the 79% upper limit imposed by reflection from the non-antireflection-coated CdZnTe substrate.