Progress in resonator quantum well infrared photodetector (R-QWIP) focal plane arrays

Abstract

h i g h l i g h t sWe report on the performance of a 640 Â 512 resonant quantum well infrared photodetector (R-QWIP) focal plane array (FPA). We report on the conversion efficiency and quantum efficiency as a function of bias and temperature. We report on the dark current and Noise Equivalent Temperature Difference as a function of bias and temperature. a r t i c l e i n f o t r a c tIn this work, the performance of a 640 Â 512 long-wavelength resonant quantum well infrared photodetector (R-QWIP) focal plane array (FPA) was evaluated as a function of operating temperature, bias, and photon flux using an F/2.2 optic. From these FPA measurements an assessment of the dark current, noise, conversion efficiency and noise-equivalent temperature difference is provided herein. Histogram results are used to support a statistical interpretation of operability and non-uniformity across the R-QWIP FPA. In addition, single pixel devices fabricated from the same wafer lot enabled supplemental noise gain and spectral response measurements. The spectral response of this R-QWIP structure was confirmed to peak around 8.3 microns with a spectral bandwidth or approximately 1 micron (full-width half maximum) and the noise gain measurements were used to provide an estimation of the expected external quantum efficiency (conversion efficiency = quantum efficiency ⁄ gain).Published by Elsevier B.V.

Improvement of tunnel compensated quantum well infrared detector

“…However, the principle of the QWIPs determines that the photocurrent of the devices is basically independent of the number of quantum wells [8] , which limits the performance of these detectors [9] . To solve this problem, researchers have proposed a variety of improved structures [10][11][12][13] . Among them, an improved quantum well infrared photodetector based on tunnel compensation was proposed.…”