A semiconductor YBaCuO microbolometer for room temperature IR imaging

Abstract

The characteristics of infrared (IR) microbolometer arrays utilizing semiconducting YBaCuO and operating at room temperature are presented. Surface-micromachined structures in the form of 1/spl times/10 arrays of pixel size 40 /spl mu/m/spl times/40 /spl mu/m and 60 /spl mu/m/spl times/60 /spl mu/m as well as single pixels of various geometries were constructed. Using the chopped radiation from a broad-band IR source, the responsivity R/sub V/ of the sensor was measured to be as high as 10/sup 4/ V/W and detectivity D* to be /spl sim/2/spl times/10/sup 7/ cm Hz/sup 1/2//W for a thermal conductance G/spl sim/10/sup -5/ W/K between the detector and the substrate. The spectral response was found to be uniform over a range of 1-12 /spl mu/m. Silicon micromachining and ambient-temperature processing were employed to ensure compatibility and, therefore, potential integration with CMOS-based signal processing circuitry. Methods of enhancing the figures of merit are discussed.