35 μm pitch at ULIS, a breakthrough

Abstract

This paper reviews ULIS’progress, on 35 μm pitch, in amorphous silicon uncooled microbolometer focal plane (UFPA) technology and product development over the last year. The ULIS FPA products have been described in great detail, including product capabilities and complete EO performances. At 60 Hz frame rate, focal planes with 40 mK (f/1) NETD are now achieved in production with a spatial fixed pattern noise lower than 25 mK after gain and offset compensation. Key improvements, compared to 45 μm pitch technology, have been the achievement of microbolometer resistance uniformity better than 0.5 % (standard deviation) on the IRFPA die for the different formats. Thanks to a new pixel design, high fill factor along with low thermal time constant (7 ms), 35 μm pitch amorphous silicon UFPAs are prime candidates for FLIR applications.