Fast neutron irradiation effects on Si- and GaN-based avalanche photodiodes

Results in Physics

卷:38

Ge Tang¹  Biao Wei²  Xiang Fu³  Jianbin Kang³  Qian Li⁴  Mo Li⁴  Wangping Wang⁴  Feiliang Chen⁵ 

[1] Corresponding authors.;

[2] Microsystem and Terahertz Research Center, China Academy of Engineering Physics, 596 Yin He Road, Shuangliu, Chengdu 610200, China;

[3] Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Chongqing University, Chongqing 400044, China;

[4] The College of Nuclear Technology and Automation Engineering, Chengdu University of Technology, Chengdu 610059, China;

关键词: Si;    GaN;    APDs;    Neutron irradiation;   

DOI  :  

来源: DOAJ

【 摘 要 】

We report the behaviour of the dark current and gain characteristics of Si- and GaN-based avalanche photodiodes (APDs) irradiated by fast neutrons. For Si-based APDs, the dark current increases with the increase of neutron fluence, indicating that the avalanche property has been seriously affected. The gain values of Si-based APD slightly increase after irradiation by a low neutron fluence of 1.0 × 1012 cm−2, while the device exhibits gain degradation as the fluence increases to 1.0 × 1013 cm−2 or even above at high reverse bias voltage, unlike the previous studies where only degradation was observed. The steep increase of dark current and gain when approaching the breakdown voltage after neutron irradiation indicate that the avalanche property is almost unaffected for GaN-based APDs. Furthermore, we infer that the optical absorption between acceptor state and conduction band in the p-type layer plays an important role in influencing the change of dark current and gain at high reverse bias voltage. The findings not only enrich the understanding of neutron irradiation effect on Si- and GaN-based APDs, but also experimentally prove that GaN-based APDs hold better radiation resistance than Si-based devices.

【 授权许可】

Unknown