Uncooled multi-band IR imaging using bimaterial cantilever FPA

This paper presents the design, fabrication and performance of a 256×256 bimaterial cantilever focal plane array (FPA) which is able to work in the three infrared (IR) atmospheric windows of 1~2.5μm, 3~5μm and 8~14μm simultaneously. The FPA employs a silicon-framed structure by selectively etching away the substrate with Deep Reactive Ion Etching technique, and a stacked layer of chromium and SiN_x serves as the multi-band absorber. The images of short wavelength, middle wavelength and long wavelength infrared were captured successfully with the same FPA by combining the Chromium nano-film with silicon nitride as the multi-band IR absorber. The measured sensitivity of the FPA is 0.18μm/K.