面向SOC新型紫外探测器特性研究及集成读出电路技术

At present the UV detection system has some disadvantages, such as low sensitivity, low integration, bulky, power consumption, etc.. The subjects of this project are to find one's way out to resolve those current shortcomings. Based on the CMOS technology features and the research experience of silicon detectors, this project researches on the theories how to improve the quantum efficiency, how to reduce noise and how to improve low light sensitivity; and then reveals the possibility of the system integrating UV detector with the signal process circuit. The above researches provide the new ideas for the single chip integrated UV detection system adopting the system on a chip method. A novel high-performance super-ultraviolet single photon avalanche photodetector structures are proposed in this project, which is to be researched through the methods of the Physical modeling, the computer simulation, the structural design, process design, and tapeout verification. A variety of the analytical models and the equivalent circuit models are established for the proposed device. Adopting the device fabrication and the testing, the silicon parameters are feedbacked the built models to improve the simulation. The interface parameters and the simulation models of the proposed device are provided for the simulation of the on-chip integrated readout circuit design. In this project, the readout circuit technology is researched for the proposed UV photodetector. One low noise and low power readout circuit structure is proposed that can effectively suppress the detector dark current and noise, increase the injection efficiency and high charge sensitivity and large dynamic range. Therefore this project provides a new signal processing circuit technology for SOC integrated UV detector. Finally, the SOC chip integrated with both the proposed UV detector and the readout circuit is tapeout and be tested. The results of this project can be applied to the fields, such as the medical, scientific and defense, etc.

目前紫外探测系统有灵敏度低、集成度低、体积庞大、功耗高等缺点，本课题从解决目前紫外探测器存在的缺点出发，基于CMOS工艺特点和已有的硅基探测器研究基础，研究提高光量子效率、降低噪声、提高弱光响应灵敏度的理论，揭示系统集成紫外探测器的可能性，为面向SOC单芯片集成紫外探测系统提供新思路，提出高性能超级紫外单光子雪崩光电探测器新结构。采用物理建模、计算模拟、结构设计、工艺设计、流片加工的研究方法，建立新器件各种光学、电学特性的解析和电路模型，通过器件制备、参数测试、反馈并改进模型，为片上集成读出电路的设计提供接口参数、仿真模型和实际器件。针对提出的新器件研究读出电路技术，提出一种具有对探测器暗电流和噪声有效抑制、注入效率和电荷灵敏度高、动态响应范围大、低噪声和高稳定的读出电路结构，为SOC集成紫外探测器提供信号处理电路新技术，并完成芯片试制和验证。本课题成果可应用于医疗、科学和国防等领域。

紫外探测技术是继激光探测技术和红外探测技术之后发展起来的又一种新颖探测技术，在军事领域中广泛应用于导弹预警、制导、紫外通讯、生化分析等；同时紫外探测技术民用方面，广泛应用于空间探测、火焰火灾检测、生物医药的分析等。本项目针对目前紫外探测技术存在探测器难与信号处理电路单片集成；紫外探测器的控制复杂，需要相对高的工作电压功耗大；成本高等缺点，基于CMOS工艺研究紫外探测技术，单芯片集成高性能紫外探测器件和信号处理电路，实现高集成度、低功耗的特点。基于硅基研究提高光量子效率、降低噪声、提高弱光响应灵敏度的原理，并提出一些新的器件结构，采用数值建模和计算机模拟，建立器件光学、电学特性解析和电路模型并进行仿真。基于理论建模和分析的基础上，进行结构设计和仿真，在0.5um、0.35um和0.18um CMOS工艺进行了3批次累计20余个器件或芯片的流片和测试，通过器件制备、参数测试、反馈并改进模型。针对设计分析的器件结构，设计了有效抑制暗电流、提高注入效率和电荷灵敏度、低噪声和低功耗读出电路技术和结构，并完成芯片试制和验证。基于上述研究工作，取得以下成果：发表论文51篇，其中SCI收录17篇（其中SCI，EI双收录16篇）、EI单收录23篇、其他期刊论文11篇；申请或获得国家知识产权24项，其中申请或授权发明专利7项（获得授权专利号3项，获得申请号4项）、获得实用新型专利2项、获得集成电路布图保护登记证书15项；培养16名硕士研究生、其中4人次获得国家奖学金；培养3名年轻科技人员；2014年获得湖南省科技进步奖三等奖1项；2015年获得中国电子学会科技进步奖1项；基于项目成果2015年获得湖南省杰出青年科学基金；2013年11月获得湖南省微光电与系统集成工程实验室。本项目提出的紫外探测器件和读出电路技术完全与CMOS工艺兼容，有望实现单芯片集成紫外探测系统，对提升国内紫外探测的技术水平具有重要意义。