Long Wavelength Resonator-Qwips

We are developing resonator-QWIPs for long wavelength applications. Detector pixels with 25 mu m pitch were hybridized to fanout circuits for radiometric measurements. With a moderate doping of 0.5 x 10(18) cm(-3), we achieved a quantum efficiency of 37% and conversion efficiency of 15% in a 1.3 mu m-thick active material and 35% QE and 21% CE in a 0.6 mu m-thick active material. Both detectors are cutoff at 10.5 mu m with a 2 mu m bandwidth. The temperature at which photocurrent equals dark current is about 65 K under F/2 optics. The thicker detector shows a large QE polarity asymmetry due to nonlinear potential drop in the QWIP material layers.