Radiation effects on GaAs/AlGaAs core/shell ensemble nanowires and nanowire infrared photodetectors

Fajun Li; Ziyuan Li; Liying Tan; Yanping Zhou; Jing Ma; Mykhaylo Lysevych; Lan Fu; Hark Hoe Tan; Chennupati Jagadish

doi:10.1088/1361-6528/aa5bad

Radiation effects on GaAs/AlGaAs core/shell ensemble nanowires and nanowire infrared photodetectors

Nanotechnology. 2017 Mar 24;28(12):125702. doi: 10.1088/1361-6528/aa5bad. Epub 2017 Jan 31.

Authors

Fajun Li¹, Ziyuan Li, Liying Tan, Yanping Zhou, Jing Ma, Mykhaylo Lysevych, Lan Fu, Hark Hoe Tan, Chennupati Jagadish

Affiliation

¹ National Key Laboratory of Tunable Laser Technology, Harbin Institute of Technology, Harbin 150001, People's Republic of China. Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra 2601, A.C.T., Australia.

PMID: 28140378
DOI: 10.1088/1361-6528/aa5bad

Abstract

With the recent advances in nanowire (NW) growth and fabrication, there has been rapid development and application of GaAs NWs in optoelectronics. It is also of importance to study the radiation tolerance of optoelectronic nano-devices for atomic energy and space-based applications. Here, photoluminescence (PL) and time-resolved photoluminescence measurements were carried out on GaAs/AlGaAs core/shell NWs at room temperature before and after 1 MeV proton irradiation with fluences ranging from 1.0 × 10¹²-3.0 × 10¹³ cm^-2. It is found that the GaAs/AlGaAs core/shell NWs with smaller diameter show much less PL degradation compared with the ones with larger diameters. The increased radiation hardness is mainly attributed to the improvement of a room temperature dynamic-annealing mechanism near the surface of the NWs. We also found that the minority carrier lifetime is closely related to both the PL intensity and defect density induced by irradiation. Finally, GaAs/AlGaAs ensemble NW photodetectors operating in the near-infrared spectral regime have been demonstrated. The influence of proton irradiation on light and dark current characteristics also indicates that NW structures are a good potential candidate for radiation harsh-environment applications.