针对表面淬灭电阻技术引起死区面积较大,以及高光子探测效率与大动态范围不能同时满足的矛盾,应用外延电阻淬灭技术,采用与雪崩光电二极管微单元相连的衬底外延层硅材料制作了淬灭电阻.研制成功的外延电阻淬灭硅光电倍增器的有源区面积为1×1mm~2,微单元尺寸为7μm,微单元密度高达21 488个/mm~2,测试结果表明:漏电流为10量级,反向击穿电压为24.5V,过偏压为2.5V时,增益达1.4×10~5,室温下暗计数率约为600kHz/mm~2,串话率低于10%,说明该器件具有良好的光子计数特性.该高密度硅光电倍增器测量的动态范围是1.8×10~4个/mm,光子探测效率为16%(@λ_(peak)=480nm),恢复时间为8.5ns,单光子分辨能力较高,并且在液氮温度环境能够探测光子,这对于拓展硅光电倍增器在极低温度条件下的应用,比如暗物质测量实验方面具有潜力.
In view of the large area of dead zone caused by the surface quenching and the contradiction between the dynamic range and the detection efficiency. By applying the epitaxial resistance quenching technology, the quenching resistance was prepared by using a substrate epitaxial layer of silicon material connected with the Avalanche Photo Diode (APD) unit. The developed Silicon Photomultiplier (SiPM) with the active area of 1 × 1mm2 is called F5 2 which micro cell size is 7μm and the density of the micro element is as high as 21 488 cells/mm2. The breakdown voltage is 24.5 V; the leakage current is on 10 pA; the gain is 1.4× 10^2 ; the dark count rate is about 600 kHz/mm2 and the crosstalk rate is about 10^5 at room temperature over bias 2. 5 V; the dynamic range is about 1. 8 ×10^4 cells/ mm2 and the Photon Detection Efficiency (PDE) peak value @480 nm is 16% ;the recovery time is about 8.5 ns. The device has good characteristics of photon counting on account of the better single photon resolution ability. Moreover it can detect photons at the liquid nitrogen temperature which has a great potential for expanding SiPM applications such as dark matter measurements at very low temperatures.