使用曲面微通道板和感应电荷位置灵敏阳极的软X射线-极紫外光子计数成像探测器研究

本项目对我国空间探测的极紫外(EUV)波段大视场相机所需求的球面光子计数成像探测器的关键技术进行了研究。首先,建立了光阴极材料次级电子产出模型,利用该模型计算了软X射线-EUV波段常用的光电阴极材料—碱卤化物的次级电子产出,分析了微通道板(MCP)的次级电子产出。建立了测量MCP量子探测效率的装置,并推导出MCP量子探测效率的计算公式,测量了MCP在软X射线-EUV波段的量子效率以及MCP量子效率随掠入射角的变化。其次,建立了球面实芯微通道板的制备装置,利用高温热成型方法制备出曲率半径为150 mm球面MCP,利用光刻技术制备出有效直径为48 mm的楔条形感应电荷位置灵敏阳极,在此基础上集成了一套使用球面MCP和感应电荷位置灵敏阳极的两维光子计数成像探测器。再次,研制出包括快速前端模拟电路与后续数字电路的成像读出电路,编制了能矫正图像畸变的图像实时采集和处理软件。最后,建立了MCP探测器空间分辨率、图像线性的检测装置,对研制出的探测器性能进行了检测,检测结果表明:探测器的各项技术指标完全满足要求。

Soft X-ray and extreme ultraviolet photon-counting imaging detector with curved surface micro-channel plate and induced charge position-sensitive anode

The research on key techniques of wide field extreme ultraviolet(EUV) spherical micro-channel plate(MCP) photon-counting imaging detector which will be used in space probe in China have been done. Firstly, the secondary electron yield model of photocathode material was built, and the secondary yield of alkali halide and MCP in soft X-ray and EUV band were calculated using the model. The measurement equipment of MCP's quantum detection efficiency also was set up. The calculated fomula of MCP's quantum efficiency was introduced, and MCP's quantum efficiency vs. wavelength and incidence angle in soft X-ray and EUV region were measured. secondly, the instrument of solid core spherical MCP fabrication was established, a set of spherical MCP with 150 mm radius were made using the instrument. The 48 mm induced charge wedge and strip anode in effective diameter was made by the use of traditional UV lithography, and the photon-counting imaging detector was integrated based on the anode and spherical MCP stack in Z configuration. Thirdly, the position readout electronics including analog frent-end and digital processing circuit and the software with image distortion rectification and real-time collection were developed. Finally, the measurement instrument of spherical MCP detector's spatial resolution and image linearity was built, and the specifications of the detector were measured using the instrument, showing that all technical specificaions of the detector satisfy the design requirements.