Modern scintillator-based radiation detectors require silicon photomultipliers(Si PMs)with photon detection efficiency higher than 40%at 420 nm,possibly extended to the vacuum ultraviolet(VUV)region,single-photon time...Modern scintillator-based radiation detectors require silicon photomultipliers(Si PMs)with photon detection efficiency higher than 40%at 420 nm,possibly extended to the vacuum ultraviolet(VUV)region,single-photon time resolution(SPTR)<100 ps,and dark count rate(DCR)<150 kcps/mm^(2).To enable single-photon time stamping,digital electronics and sensitive microcells need to be integrated in the same CMOS substrate,with a readout frame rate higher than 5 MHz for arrays extending over a total area up to 4 mm×4 mm.This is challenging due to the increasing doping concentrations at low CMOS scales,deep-level carrier generation in shallow trench isolation fabrication,and power consumption,among others.The advances at 350 and 110 nm CMOS nodes are benchmarked against available Si PMs obtained in CMOS and commercial customized technologies.The concept of digital multithreshold Si PMs with a single microcell readout is finally reported,proposing a possible direction toward fully digital scintillator-based radiation detectors.展开更多
中国神州系列飞船的成功发射和天宫系列建设任务的顺利实施,再次引发航天潮.美国提出了重返月球、登陆火星等计划(NASA Strategic Plan 2014,www.NASA.gov),俄罗斯、日本和印度等国也不甘落后,欧洲甚至提出移民火星.但是,外太空是个混...中国神州系列飞船的成功发射和天宫系列建设任务的顺利实施,再次引发航天潮.美国提出了重返月球、登陆火星等计划(NASA Strategic Plan 2014,www.NASA.gov),俄罗斯、日本和印度等国也不甘落后,欧洲甚至提出移民火星.但是,外太空是个混合辐照场,空间辐射的能量高、富含高能带电(high atomic number and high energy,HZE)粒子,对航天员的健康威胁在任何情况下都必然存在,是任何空间探索任务都不可回避的问题.对于登陆火星和月球殖民等长周期深空探索任务而言,航天员面临的最大挑战是空间辐射诱导的肿瘤发生、心血管疾病等健康问题.如果遭遇太阳粒子事件等空间灾害事件,还将面临急性放射损伤甚至生命威胁,这些健康威胁属于show-stopper(搅局者)[1],现有空间辐射相关健康风险评估标准显然是不够的.降低空间辐射危害评估的不确定性,建立医学健康标准和安全评价体系,研发有效的防护措施,才能保障航天员的作业能力和健康安全.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62250002,62027808,and 62027801)the Sino-German Mobility Programme(No.M-0387)。
文摘Modern scintillator-based radiation detectors require silicon photomultipliers(Si PMs)with photon detection efficiency higher than 40%at 420 nm,possibly extended to the vacuum ultraviolet(VUV)region,single-photon time resolution(SPTR)<100 ps,and dark count rate(DCR)<150 kcps/mm^(2).To enable single-photon time stamping,digital electronics and sensitive microcells need to be integrated in the same CMOS substrate,with a readout frame rate higher than 5 MHz for arrays extending over a total area up to 4 mm×4 mm.This is challenging due to the increasing doping concentrations at low CMOS scales,deep-level carrier generation in shallow trench isolation fabrication,and power consumption,among others.The advances at 350 and 110 nm CMOS nodes are benchmarked against available Si PMs obtained in CMOS and commercial customized technologies.The concept of digital multithreshold Si PMs with a single microcell readout is finally reported,proposing a possible direction toward fully digital scintillator-based radiation detectors.
基金supported by the Natural Science Foundation of Hebei Province of China(E2020203085,E2022203109)the National Natural Science Foundation of China(52090022,52288102)。
文摘中国神州系列飞船的成功发射和天宫系列建设任务的顺利实施,再次引发航天潮.美国提出了重返月球、登陆火星等计划(NASA Strategic Plan 2014,www.NASA.gov),俄罗斯、日本和印度等国也不甘落后,欧洲甚至提出移民火星.但是,外太空是个混合辐照场,空间辐射的能量高、富含高能带电(high atomic number and high energy,HZE)粒子,对航天员的健康威胁在任何情况下都必然存在,是任何空间探索任务都不可回避的问题.对于登陆火星和月球殖民等长周期深空探索任务而言,航天员面临的最大挑战是空间辐射诱导的肿瘤发生、心血管疾病等健康问题.如果遭遇太阳粒子事件等空间灾害事件,还将面临急性放射损伤甚至生命威胁,这些健康威胁属于show-stopper(搅局者)[1],现有空间辐射相关健康风险评估标准显然是不够的.降低空间辐射危害评估的不确定性,建立医学健康标准和安全评价体系,研发有效的防护措施,才能保障航天员的作业能力和健康安全.
