Micromachined VO{sub}2-based uncooled IR bolometric detector arrays with integrated CMOS readout electronics

摘要

Uncooled IR bolometric detectors fabricated using surface silicon micromachining are presented. The detector fabrication process employs a polyimide sacrificial layer, and a VO{sub}2 thermistor layer exhibiting a thermal coefficient of resistance on the order of -3 %/°C. Detector sizes are 100 μm× 100 μm and 50 μm×50μm and 64 × 64 and 128 × 128 pixel arrays are fabricated. The detectors exhibit responsivities of up to 15 000 VW{sup}(-1), normalized detectivities typically exceeding 10{sup}8 cm Hz{sup}(1/2)W{sub}(-1) and response times below 20 ms. Three integrated readout circuit designs for 64 × 64 and 128 × 128 pixel detector arrays, fabricated using a standard 1.5 μm CMOS process, are described. These circuits include several test and detector nonuniformity correction features and can operate in either self scanning mode at a rate of 30 frames per second, or in the random access mode in which column and row addresses are input directly.