Development of shutter-less SOI diode uncooled IRFPA for compact size and low power consumption

In this study, we develop a shutter-less algorithm for a silicon-on-insulator (SOI) diode uncooled infrared focal plane array (IRFPA). The optimal non-uniformity correction is calculated onboard. The effectiveness of the proposed algorithm was verified using a prototype uncooled IR camera. The performance of the shutter-less algorithm was studied by measuring a fixed pattern noise (FPN) at different correction points and verification of favorable camera operation. Even at two correction points, the FPN was at a practical level. The temperature behavior of the proposed SOI diode is highly uniform and predictable, which leads to simpler device modeling and therefore simpler shutter-less operation. A new pixel structure was also developed for pixel size reduction. This approach is based on the realization of a novel thermal isolation structure that can be fabricated by post processing on top of CMOS wafers. Ten series diodes can be arranged in a pixel by designing a 12 μm pixel pitch IRFPA with the new pixel structure. These developed technologies have significantly enhanced the performance of the SOI diode uncooled IRFPA, which inherently possesses excellent uniformity and low noise.