基于事件采样的微秒量级时间分辨率X射线CMOS图像传感器关键技术研究

High time resolution detection on cosmic X ray is of great importance for humans to understand the formation and evolution of celestial bodies. The image sensors manufactured from silicon on insulator (SOI, Silicon-On-Insulator) have the great potential of realizing microsecond time resolution detection on cosmic X ray. This project intends to look at the research subject from two perspectives, which are.signal collection and signal sampling. Specifically, the content of the project includes design theories on CMOS image sensor pixel with microsecond time resolution and sampling methods of image sensor pixel array. By means of theoretical computation，device simulation and experimental verification, the research will reveal the metrics of how sub-silicon characteristics and pixel bias conditions influence microsecond time resolution CMOS image sensor pixel’s signal charge collection efficiency and will realize microsecond time resolution CMOS.image sensor pixel with low dark current and high charge collection efficiency. On basis of that, the project will start the research of incident event marking method based on threshold and intelligent recognition method of sensitive area, aiming to abandon frame sampling used in traditional image sensors and to realize high speed sensitive area information sampling based on incident trigger event. Conclusively, the project will achieve optimization for image sensor pixel design theories and image sensor read-out circuit design methods, and will provide.theoretical foundation to the microsecond time resolution detection on X ray.

宇宙X射线高时间分辨率探测对人类认识天体的形成和演化规律具有重要意义。利用绝缘体上硅（SOI，Silicon-On-Insulator）技术制造的CMOS图像传感器具有实现宇宙X射线微秒量级时间分辨率探测的巨大潜力。本项目拟从信号收集和采样两方面开展研究，具体包括微秒量级时间分辨率CMOS图像传感器像素设计理论和像素阵列采样方法：通过理论计算、器件仿真、实验验证等手段研究衬底硅特性及动态偏置条件对微秒量级时间分辨率像素电荷收集效率的影响机理，实现低暗电流、高收集效率的微秒量级时间分辨率像素；在此基础上研究基于阈值判定的入射事件标记方法和敏感区域智能识别方法，摒弃传统图像传感器基于“帧”的采样方式，实现基于事件触发的像素阵列敏感区域信息高速采样。最终在图像传感器核心器件设计理论、图像传感器读出电路设计方法等方面取得科研成果，为实现微秒量级时间分辨率X射线探测提供理论支持。

宇宙X射线高时间分辨率探测对人类认识天体的形成和演化规律具有重要意义。利用绝缘体上硅（SOI，Silicon-On-Insulator）技术制造的CMOS图像传感器具有实现宇宙X射线微秒量级时间分辨率探测的巨大潜力。本项目从信号收集和采样两方面开展研究，具体包括微秒量级时间分辨率CMOS图像传感器像素设计理论和像素阵列采样方法：通过理论计算、器件仿真、实验验证等手段研究像素电荷收集效率提升方法，实现低暗电流、高收集效率的微秒量级时间分辨率像素，最终设计了基于SOI工艺的X射线微秒量级时间分辨率像素阵列，并进行了流片验证；在此基础上研究基于阈值判定的入射事件标记方法和敏感区域智能识别方法，包括基于人工智能的图像识别硬件计算加速平台设计，摒弃传统图像传感器基于“帧”的采样方式，实现基于事件触发的像素阵列敏感区域信息高速采样。最终在图像传感器核心器件设计理论、图像传感器读出电路设计方法等方面取得科研成果，为实现微秒量级时间分辨率X射线探测提供理论支持。