High-performance uncooled amorphous silicon video graphics array and extended graphics array infrared focal plane arrays with 17-μm pixel pitch

The high level of accumulated expertise by ULIS and CEA/LETI on uncooled microbolometers made from amorphous silicon with 45, 35, and 25 μm enables ULIS to develop video graphics array (VGA) and extended graphics array (XGA) infrared focal plane array (IRFPA) formats with 17-μm pixel pitch to fulfill every application. These detectors keep all the recent innovations developed on the 25-μm pixel-pitch read out integrated circuit (ROIC) (detector configuration by serial link, low power consumption, and wide electrical dynamic range). The specific appeal of these units lies in the high spatial resolution it provides while keeping the small thermal time constant. The reduction of the pixel pitch turns the VGA array into a product well adapted for high-resolution and compact systems and the XGA a product well adapted for high-resolution imaging systems. High electro-optical performances have been demonstrated with noise equivalent temperature difference (NETD) < 50 mK. We insist on NETD and wide thermal dynamic range trade-off, and on the high characteristics uniformity achieved thanks to the mastering of the amorphous silicon technology as well as the ROIC design. This technology node paves the way to high-end products as well as low-end, compact, smaller formats, such as 320 × 240 and 160 × 120 or smaller.