C-QWIP focal plane array development

ARL and L3-CE have been developing corrugated quantum well infrared photodetector (C-QWIP) technology for long wavelength applications. Several large format 1024 × 1024 C-QWIP focal plane arrays (FPAs) have been demonstrated. In this paper, we provide a detailed analysis on the FPA performance in terms of quantum efficiency η and compare it with a detector model. We found excellent agreement between theory and experiment when both the material parameters and the pixel geometry are taken into account. For C-QWIPs with the bound-to-quasi-bound structure, a η of 37% is observed, albeit at a large voltage of -11V. Since this voltage is outside the operating regime of the existing readout electronics, we investigated several more compatible structures and achieved η in the range of 15 - 26%. This range of η, although lower than the original value, is still approximately three times higher than that of the grating coupled QWIPs, and the coupling bandwidth is also three times wider. The C-QWIP approach thus holds significant performance advantages over the grating approach. Combined with its economical processing steps and flexible wavelength coverage, the C-QWIP technology has proven its advantages in infrared detection.