ATTAINMENT OF HIGH-SENSITIVITY AT ELEVATED OPERATING TEMPERATURES WITH STARING HYBRID HGCDTE-ON-SAPPHIRE FOCAL-PLANE ARRAYS

Cost-effective high-performance IR imaging cameras need affordable sta ring focal plane arrays (FPAs) that can operate effectively at tempera tures compatible with inexpensive long-life coolers. We report on star ing hybrid 128 x 128 and 256 x 256 Hg1-xCdxTe FPAs that have requisite yield, sensitivity, operability, and reliability at a medium-waveleng th IR (MWIR) cutoff wavelength (lambda approximately 4.6 mum at 180 K) and elevated operating temperatures. Mean 256 x 256 FPA noise-equival ent temperature differences (NEDELTAT) using broadband f/1.7 optics we re 4.3, 7.7, and 55 mK at 120, 140, and 180 K, respectively. We extrap olate that camera NEDELTAT less-than-or-equal-to 0.02 K can be achieve d at 190 K using optimized lambda(c) of approximately 4.4 mum (180 K), a 3.4- to 4.2-mum bandpass filter, and f/1 optics. Because the CMOS m ultiplexers have a low-power dissipation and need little ancillary cir cuitry in the dewar, a viable thermoelectrically-cooled FPA technology is thus implied once the lambda(c) is optimized for MWIR imaging.