Study on irradiation-induced defects in GaAs/AlGaAs core–shell nanowires via photoluminescence techn

• 作 者: 谭立英 黎发军 谢小龙 周彦平 马晶
• 机 构: National Key Laboratory of Tunable Laser Technology, Harbin Institute of Technology,
• 出 处: Chinese Physics B
• 发表日期: 2017年08期
• 关键词: irradiation lifetime defects AlGaAs proton recombination minority behave normali

To gain a physical insight into the radiation effect on nanowires(NWs), the time resolved photoluminescence(TRPL)technique is used to investigate the carrier dynamic behaviors in GaAs/AlGaAs core–shell NWs before and after 1-MeV proton irradiation with fluences ranging from 1.0 × 10~(12) cm~(-2) to 3.0 × 10~(13) cm~(-2). It is found that the degradations of spectral peak intensity and minority carrier lifetime show similar trends against irradiation fluence, which is closely related to the displacement defects induced by irradiation. We also find that the proton irradiation-induced defects behave as Shockley–Read–Hall(SRH) recombination center trapping free carriers. Finally, the defect concentration could be estimated through measuring the minority carrier lifetime.

To gain a physical insight into the radiation effect on nanowires (NWs), the time resolved photoluminescence (TRPL) technique is used to investigate the carrier dynamic behaviors in GaAs / AlGaAs core-shell NWs before and after 1-MeV proton irradiation with fluences ranging from 1.0 × 10-12 cm -2 to 3.0 × 10-13 cm -2. It is found that the degradations of spectral peak intensity and minority carrier lifetime show similar similar against irradiation fluence, which is closely related to the displacement defects induced by irradiation. We also find that the proton irradiation-induced defects behave as Shockley-Read-Hall (SRH) recombination center trapping free carriers. Finally, the defect concentration could be estimated through measuring the minority carrier lifetime.