基于低温原位掺杂技术的大面积硅漂移探测器研究

随着我国“神州”、“嫦娥”、“萤火”计划的进行，我国深空探测将进入一个全新的时期，研制具有高能量分辨率的大面积硅漂移探测器（SDD）对于突破国内脉冲星自主定位导航系统的技术瓶颈具有极其重要的意义。由于传统的SDD采用离子注入技术形成PN结，制备工艺的温度较高，导致衬底质量劣化，而且注入过程导致衬底表面损伤，器件漏电流增大，不利于器件能量分辨率的提高。本项目采用TCAD软件建立SDD的器件物理结构模型，通过仿真模拟明确了高能量分辨率大面积SDD的结构设计机理。创新的设计双面对称阳极穿通型SDD，将硅锗薄膜的低温原位掺杂技术应用到SDD，并对其工艺制备技术进行深入研究，制备工艺温度不超过550oC。合理设计SDD的漂移环、保护环及分压器，逐步攻克高能量分辨率SDD在制备工艺及测试等环节的关键技术难点，为我国高能量分辨率大面积SDD突破提供重要理论和技术基础。

With the implementation of China's "shenzhou", "chang’ e", "Yinghuo" plans, deep space exploration in our country will enter a new period. The development of Silicon Drift Detector (SDD) with high energy resolution is of great significance to breakthrough the technical bottleneck of pulsar autonomous navigation system. The traditional SDD was fabricated by ion implantation, and the process temperature is so high that the substrate quality was degraded. Further, the substrate surface was damaged during the implantation, resulting in high leak current of the detector, and thus a low energy resolution. In this project, TCAD will be applied to establish the physical structure model of SDD, and the mechanism of designing high energy resolution large-area SDD will be clear. Novel SDD is designed with double-side symmetric structure, where anodes are connected by a punched hole. Meanwhile, in-situ doped SiGe thin films prepared at low temperature (≤ 550oC) will be applied into SDD, and the whole fabrication process will be intensively studied. The drift rings, protection rings and the voltage divider of SDD will be precisely designed, and the key technical difficulties in the preparation process and test of high-energy resolution SDD will be solved. Finally, important theoretical and technical basis of high energy-resolution large-area SDD can be provided for our country.