Quantum well infrared photodetectors

Abstract

We summarize the current state of Quantum Well Infrared Photodetector (QWIP) Focal Plane Array (FPA) technology. One-color longwave (LW) and midwave (MW) infrared FPAs in formats up to 640×480 are being produced by several groups. We recently demonstrated 2-color QWIP FPAs with spatially-registered simultaneous imagery. Our 2-color FPA architecture features 3 bumps/pixel to permit two vertically stacked QWIPs to be separately biased and the two photocurrents to be simultaneously integrated. We successfully applied this architecture to realize 2-color FPAs in three separate formats: LW/LW, MW/LW, and MW/MW. Fabrication and performance details are presented.