We investigated the effects of H+ ion irradiation on a chalcogenide Cu(In,Ga)Se2 (CIGS) thin film as a function of the dose concentration (1014 ∼ 1016/cm2) at 200 keV by using time-resolved THz spectroscopy. The optical conductivity of these films was derived from THz time-domain spectroscopy (THz-TDS) in the THz region. THz emission spectroscopy revealed the emission of a strong-intensity THz pulse from the H+ ion-irradiated CIGS thin film. This is explained by considering the ultrafast behavior of photocarriers, resulting in strong surface band bending induced by the built-in potential with a conversion of the CIGS thin film from p- to n-type. Finally, we used optical pump THz probe spectroscopy to examine the ultrafast photocarrier dynamics determined by the time of capture at the increased number of surface and bulk defect states. This clearly showed that irradiation with H+ ions could generate a number of defect states while simultaneously pacifying the Cu vacancy defects.

中文翻译：

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太赫兹区 Cu(In,Ga)Se2 薄膜氢离子辐照诱导的超快光激发载流子行为


我们利用时间分辨太赫兹光谱研究了 200 keV 下 H+ 离子辐照对硫族化物 Cu(In,Ga)Se2 (CIGS) 薄膜的影响与剂量浓度 (1014 ∼ 1016/cm2) 的函数关系。这些薄膜的光导率来自太赫兹区域的太赫兹时域光谱（THz-TDS）。太赫兹发射光谱显示 H+ 离子辐照的 CIGS 薄膜发射强强度太赫兹脉冲。这是通过考虑光载流子的超快行为来解释的，随着 CIGS 薄膜从 p 型到 n 型的转换，内置电势会导致强烈的表面能带弯曲。最后，我们使用光泵太赫兹探针光谱来检查由表面和体缺陷态数量增加的捕获时间决定的超快光载流子动力学。这清楚地表明，H+离子辐照可以产生多种缺陷态，同时平息铜空位缺陷。