Novel infrared absorbing material coupled uncooled microbolometer

Abstract

A novel infrared absorbing material for an uncooled microbolometer was developed and a microbolometer was designed and fabricated using the new bolometric material. The new infrared absorbing material was fabricated based on the formation (by cosputtering) of a vanadium-tungsten alloy film and its oxidation. The new bolometric material has TCR values in the range of -1.5 to -4.0 %/K, depending on the variation of tungsten concentration and oxidation time. The novel infrared absorbing material coupled microbolometer was fabricated by surface micromachining and its bolometric properties were characterized. Finally, the responsivity and noise voltage were measured as a function of chopper frequency, and detectivities of 0.9-6.0/spl times/10/sup 8/ cmHz/sup 1/2//W were obtained at chopper frequencies of 10-100 Hz and bias current of 33 /spl mu/A.