Active and passive infrared imager based on short-wave and mid-wave type-II superlattice dual-band detectors

作者：Huang Edward Kwei wei; Haddadi Abbas; Chen Guanxi; Anh Minh Hoang; Razeghi Manijeh^*

来源：Optics Letters, 2013, 38(1): 22-24.

A versatile dual-band detector capable of active and passive use is demonstrated using short-wave (SW) and mid-wave (MW) IR type-II superlattice photodiodes. A bilayer etch-stop scheme is introduced for back-side-illuminated detectors, which enhanced the external quantum efficiency both in the SWIR and MWIR spectral regions. Temperature-dependent dark current measurements of pixel-sized 27 mu m detectors found the dark current density to be similar to 1 x 10(-5) A/cm(2) for the similar to 4.2 mu m cutoff MWIR channel at 140 K. This corresponded to a reasonable imager noise equivalent difference in temperature of similar to 49 mK using F/2.3 optics and a 10 ms integration time (t(int)), which lowered to similar to 13 mK at 110 K using t(int) = 30 ms, illustrating the potential for high-temperature operation. The SWIR channel was found to be limited by readout noise below 150 K. Excellent imagery from the dual-band imager exemplifying pixel coincidence is shown.

• 出版日期2013-1-1
• 单位西北大学