可见光盲SiC紫外雪崩光电二极管  

SiC Visible Light Blindness UV Avalanche Photodiodes

作　　者：杨成东 苏琳琳 夏开鹏 马文烨 Yang Chengdong;Su Linlin;Xia Kaipeng;Ma Wenye(School of Electronic Information Engineering,Wuxi University,Wuxi 214105,Jiangsu,China)

机构地区：[1]无锡学院电子信息工程学院,江苏无锡214105

出　　处：《中国激光》2022年第24期15-19,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金(62106111);无锡学院引进人才科研启动项目(2021r011,2021r012)。

摘　　要：SiC雪崩光电二极管(APD)是用于探测微弱紫外光的优选器件。通过研究器件在高压下的光响应行为,发现随着偏压的增加,器件响应峰值和截止波长始终稳定在280 nm和380 nm处,表明SiC APD在雪崩击穿状态下仍具有可见光盲特性。这说明SiC APD在进行微弱紫外光探测时,凭借材料本身性质便可屏蔽可见及红外光的影响,有利于降低器件复杂度和成本。另外,为了增大器件的感光面积,将SiC APD直径增大到500μm,器件在95%击穿电压下,暗电流仅为2×10^(-10)A,当暗计数为1 Hz/μm^(2)时,器件单光子探测效率为0.7%,实现了SiC APD尺寸上的突破。Objective High-sensitivity ultraviolet(UV)detectors are required in many critical applications such as corona discharge,m issile plume detection,environmental monitoring,and non-line-of-sight communications.As an attractive candidate for weak UV signal detection,avalanche photodiodes(APDs)operating in Geiger mode exhibit promising performance,including small size,low dark current,and high multiplication gain.Wide-bandgap semiconductor materials,such as Ga N and Si C,can effectively shield the influence of visible light and infrared light,showing obvious advantages in the field of UV detection.The defect density of Ga Nis relatively high,which leads to a generally high dark current in Ga NAPDs.In addition,the photoresponse behavior of Ga NAPDs under high pressure undergoes a significant red shift,and the cut-off wavelength is extended to 440 nm,indicating the loss of visible light blindness.In comparison,Si Ccan construct APDs with a much lower dark current than Ga Nowin g to its excellent material epitaxial technology.However,there is still little research on the high-voltage photoresponse characteristics of Si CAPDs,which are a key issue related to the background noise of the device.This work discusses the photoresponse behavior of Si CAPD under high voltages.Moreover,owing to material defects,the size of the Si CAPD is always below 300μm,but a device with a large photosensitive area is needed to improve the detection sensitivity.Although some studies have reported Si CAPDs with a diameter of 800μm,the key parameter of the single-photon detection efficiency has not been successfully detected.In this study,low-dark-current Si C APDs with a diameter of 500μm were successfully fabricated,and the devices exhibited single-photon detection performance.This is clearly a breakthrough in terms of the size of Si CAPDs.Methods Si CAPDs were fabricated on n-type 4H-Si Csubstrates(Fig.1).The epi-structure from bottom to top consists o f a 10μm p+layer(NA=3×1018cm^(-3)),a 0.78μm n-multiplication layer(ND=1×1015cm^(-3))

关 键 词：激光器 SIC 雪崩光电二极管 可见光盲 大面积 

分 类 号：O47[理学—半导体物理]