MULTISPECTRAL INFRARED IMAGING ARRAY USING ALGAAS/GAAS MULTIPLE QUANTUM WELLS

WE PROPOSE TO DEVELOP A MULTISPECTRAL INFRARED (IR) IMAGING SYSTEM USING ALGAAS/GAAS MULTIPLE QUANTUM WELLS (MQW) FOCAL PLANE ARRAYS (FPAS) FOR DETECTING RADIATION IN MULTIPLE SPECTRAL BANDS. THE DETECTOR STRUCTURE COMPRISES A VERTICAL STACK OF TWO (OR MORE) DIFFERENT PERIODICITY OF MQWS: ONE CORRESPONDS TO LONG-WAVELENGTH (LWIR, 8-12 MICRON) AND THE OTHER CORRESPONDS TO MEDIUM-WAVELENGTH (MWIR, 3-5 MICRON) FORMING A TWO-COLOR (OR MULTI-COLOR) IMAGING ARRAY. THE RESULTANT MULTISPECTRAL IR IMAGING ARRAY IS CAPABLE OF MEASURING SIMULTANEOUSLY SPATIAL AS WELL AS SPECTRAL DISTRIBUTIONS OF IR TARGETS FOR TARGET RECOGNITION AND DISCRIMINATION AGAINST CLUTTER OR DECOYS. A PLASMA-ASSISTED METALORGANIC MOLECULAR BEAM EPITAXY (PAMOMBE) PROCESS WILL BE USED TO GROW MQW STRUCTURES. IN PHASE I, WE WILL DESIGN ULTRA-HIGH VACUUM FIXTURES FOR EPITAXY TO ACHIEVE A HIGH GROWTH RATE UNDER AN ULTRA-PURE MBE GROWTH ENVIRONMENT AND DELINEATE THE PAMOMBE PROCESSES TO GROW THE MQW DEVICES. WE WILL ALSO EVALUATE THE SYSTEM PERFORMANCE OF MULTISPECTRAL IR IMAGER WITH THE FPAS AND READOUT ELECTRONICS. IN SUBSEQUENT PHASES, WE WILL FABRICATE SEVERAL MQWS ONE ON TOP OF ANOTHER FORMING A VERTICAL STACK OF IR DETECTORS. THESE STACKS WILL THEN BE FABRICATED INTO A 2-DIMENSIONAL ARRAY FORM FOR MULTISPECTRAL IMAGING AND WILL BE MONOLITHICALLY INTEGRATED TO THE MULTIPLEXER AND READOUT ELECTRONICS. IR SPECTROSCOPY, IR DETECTOR ARRAYS, THERMAL IMAGING, IR SURVEILLANCE, IMAGING, SMART MUNITIONS THAT ARE LIGHT WEIGHT AND HIGH PERFORMANCE.