抗辐射低噪声CMOS图像传感器设计技术研究

Research on the Design Technology of Radiation Hardened Low Noise CMOS Image Sensor

为满足航天应用对大面阵高动态CMOS图像传感器的需求,对噪声优化与辐射加固等关键技术进行了深入研究。基于系统架构的增益级与双相关双采样设计优化、基于采样电路的时序改进,实现了对系统噪声的多层次优化;基于像素级与电路级的总剂量辐射加固与单粒子闩锁辐射加固设计,实现了对100k rad(Si)总剂量和99.8 MeV·cm2/mg单粒子效应的免疫。研究成果已成功应用于一款64M像素超大面阵高性能CMOS图像传感器产品。流片测试结果显示,抗总剂量辐射能力优于100k rad(Si)、暗电流与噪声随辐射增长率提升了一个数量级;抗单粒子闩锁能力优于99.8 MeV·cm2/mg;在整个辐射环境下读出噪声不超过5e-;本征动态范围高达75dB。

To meet the requirement of large array and wide dynamic range CMOS image sensor in space application,the noise optimization and radiation hardened design are studied. The noise suppression technology is studied from the aspects of system structure optimization,circuit topology and logic improvement. The reliability design of large array CMOS image sensor for space applications is discussed through radiation-hardened design based on pixel and single event latch up based on circuit and layout. The research results have been successfully applied to 64M pixel super large array CMOS image sensor. Measurement results show that TID is better than 75k rad(Si),dark current and noise increasing ratio is better than the same product one degree,and SEL threshold is better than 99.8 MeV·cm2/mg. Under the whole irradiation environment,the read noise is not exceeding 5e-,and intrinsic dynamic range is up to 75 dB.