A 9 megapixel large-area back-thinned CMOS sensor with high sensitivity and high frame-rate for the TAOS Ⅱ program

摘要

The Transneptunian Automated Occultation Survey (TAOS Ⅱ) is a robotic telescope system using three telescopes in San Pedro Martir Observatory in Mexico. It measures occultation of background stars by small TransNeptunian Objects (TNO) in order to determine their size distribution. Each telescope focal plane uses ten buttable backthinned CMOS sensors. Key performance features of the sensors are: Large array format 4608 × 1920, Pixel size 16μm, Multi ROIs, 8 analogue video channels, Frame rate of 20-40 fps [using ROIs], Low noise ＜3e-, Cryogenic dark current ＜0.1e~-/pixel/s, backthinned for ＞90% peak quantum efficiency. The paper describes top level application requirements for the TAOS Ⅱ detector. The sensor design including the pixel and buttable package are described together with performance at room temperature and cryogenic temperature of backthinned devices. The key performance specifications have been demonstrated and will be presented. The production set of 40 devices are due for completion within 2017.