大长径比微通道板电子清刷实验研究  

Experimental Research on Electron Scrubbing of Microchannel Plates with High Aspect Ratio

作　　者：闫保军 刘术林[1,2] YAN Bao-jun;LIU Shu-lin(State Key Laboratory of Particle Detection and Electronics,Institute of High Energy Physics of Chinese Academy of Sciences,Beijing 100049,China;School of Nuclear Science and Technology,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院高能物理研究所核探测与核电子学国家重点实验室,北京100049 [2]中国科学院大学核科学与技术学院,北京100049

出　　处：《真空电子技术》2024年第6期1-9,共9页Vacuum Electronics

基　　金：核探测与核电子学国家重点实验室资助项目(SKLPDE-ZZ-202412);国家自然科学基金面上项目(11675278,11975017)。

摘　　要：电子清刷实验对于评估微通道板(Microchannel plate,MCP)的体电阻、增益、累计拾取电荷量和寿命等性能参数具有重要意义。利用电子清刷系统在5×10-5Pa真空设备内,分别对两片长径比为80∶1、孔径为6μm、外径为25 mm的MCP进行了电子清刷实验研究,其中一片MCP表面及其通道内生长了氧化铝薄膜。通过改变清刷时间、剂量及次数和MCP工作电压,探索了电子清刷工艺。两片MCP的清刷次数、清刷总时间和累计拾取电荷量分别为21次和55次、1134 min和4460 min、263 mC和2329 mC。通过测试清刷前后MCP体电阻、增益和工作电压的关系,以及增益和清刷剂量之间的关系,详细评估了清刷工艺对MCP性能参数的影响。结果表明,进行大剂量清刷时,电子枪位置与MCP之间距离太小会造成MCP在清刷过程中由于受热严重而损坏;对于传统长径比为80∶1的MCP,其经过电子清刷后的稳定体电阻值高于清刷前的体电阻值,而对于镀膜氧化铝的MCP,经过电子清刷后的稳定体电阻值低于清刷前的体电阻值;经过电子清刷后,立即测试MCP体电阻值和增益,测试结果偏小,随着等待时间的延长,体电阻和增益会逐渐升高并趋于稳定;对每次清刷结束后立即测试MCP的体电阻值进行比较,可以有效判断MCP在清刷过程中的状态是否正常;随着清刷剂量的增多,在较低的工作电压下,MCP的增益迅速降低并很快趋于稳定;镀膜MCP的累计拾取电荷量可以超过2329 mC,其在不同工作电压下的稳定增益约为5~300。The electron scrubbing experiment is of great significance for evaluating the performance parame-ters of microchannel plates(MCPs),such as body resistance,gain,cumulative extracted charge and lifetime.Two MCPs with aspect ratio of 80:1,pore size of 6μm,and outer diameter of 25 mm are separately investigated using an electron scrubbing system in a 5×10-5 Pa vacuum equipment,one of the MCPs is coated with alumina thin film.By changing the scrubbing time,scrubbing dosage,scrubbing times,and MCP working voltage,the electron scrubbing process is investigated.The scrubbing times,total scrubbing time,and cumulative extracted charge of the two MCPs are 21 and 55 times,1134 and 4460 minutes,263 and 2329 mC,respectively.By testing the relationship between MCP body resistance,gain,and operating voltage before and after electron scrubbing,as well as the relationship between gain and scrubbing dose,the effects of electron scrubbing process on MCP performance parameters are evaluated in detail.The results show that when performing high-dose scrubbing,a small position gap between the electron gun and MCP can cause MCP damage due to severe heating during the scrubbing process.For the traditional 80:1 MCP,the stable body resistance value after electron scrubbing is higher than that before scrubbing,while for the MCP coated with alumina film,the stable body resistance value after scrubbing is lower than that before scrubbing.After scrubbing,when the MCP body resistance and gain are imme-diately tested,the test results are relatively small;as the waiting time extends,the body resistance and gain are gradually increase and tend to stabilize.After each scrubbing,comparing the immediately tested body resistance values of the MCP can effectively determine whether the state of the MCP during the scrubbing process is nor-mal.As the scrubbing dose increases,the gain of MCP rapidly decreases and tends to stabilize quickly under low operating voltage.The cumulative extracted charge of coated MCP can exceed 2329 mC,and the stable gain at d

关 键 词：微通道板 电子清刷 累计拾取电荷量 寿命 

分 类 号：TN15[电子电信—物理电子学]