A Global Shutter Wide Dynamic Range Soft X-Ray CMOS Image Sensor With Backside- Illuminated Pinned Photodiode, Two-Stage Lateral Overflow Integration Capacitor, and Voltage Domain Memory Bank
Hiroya Shike, Rihito Kuroda, Ryota Kobayashi, Maasa Murata, Yasuyuki Fujihara, Manabu Suzuki, Shoma Harada, Taku Shibaguchi, Naoya Kuriyama, Takaki Hatsui, Jun Miyawaki, Tetsuo Harada, Yuichi Yamasaki, Takeo Watanabe, Yoshihisa Harada, Shigetoshi Sugawa
Abstract
This article presents a prototype 22.4 μ\textm pixel pitch global shutter (GS) wide dynamic range (WDR) soft X-ray CMOS image sensor (sxCMOS). Backside-illuminated (BSI) pinned photodiodes with a 45- μ\textm thick Si substrate were introduced for low noise and high radiation hardness to high energy photons. Two-stage lateral overflow integration capacitor (LOFIC) and voltage domain memory bank with high-density Si trench capacitors were introduced for WDR and for GS. The developed sxCMOS achieved maximum 21.9 Me <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> full well capacity with a single exposure 129 dB dynamic range by GS operation. Over 70% quantum efficiency (QE) toward soft X-ray was successfully achieved. The developed prototype sxCMOS is a step forward toward a 4 M pixel detector system to be utilized in next-generation synchrotron radiation facilities and X-ray free-electron lasers.