Abstract Two-dimensional (2D) van der Waals (vdW) materials-based photodetectors have attracted great attention because of quick response time, excellent photoresponsivity and high light/dark current ratio. α-In2Se3 is one of the interesting 2D vdW materials for photodetectors because of the interrelated in-plane (IP) and out-of-plane (OOP) polarizations. It has been demonstrated that the polarizations can be used to regulate photoresponsivity of the α-In2Se3 nanoflakes based photodetectors. In addition, domain evolution may be related to the photoresponsivity degradation when the α-In2Se3 nanoflakes based photodetectors are in radiation environment. However, it is still unclear the effect of ionization and displacement damage on photoresponsivity induced by radiation particles. In this article, the α-In2Se3 based transistors for photodetectors are exposed in the 60Co γ-rays environment to induce the photoresponsivity degradation, all the channel width is about 95–100 μm for observing significant radiation effects. In order to investigate the intrinsic photoresponsivity degradation of the α-In2Se3 based transistors, a 405 nm laser is used as the light source to measure the photoresponsivity. The photoresponsivity of the devices is significantly degraded with increasing irradiation dose. Besides these, the dark current and Se atoms ratio decrease as the increasing of total dose. It may show complicate coupling radiation effect that the domain evolution induced by both the ionization effect and displacement effect promotes the photoresponsivity degradation. After a total dose of 1 Mrad (Si) 60Co γ-rays, the photodetector can still be used to detect the light with a high photoresponsivity of about 107 A/W when the input optical power density is about 454 μW/cm2. Our results may promote the investigation of radiation effect in 2D vdW materials-based photodetectors.

中文翻译：

---

用于光电探测器的基于 α-In2Se3 的晶体管的电离效应和位移效应引起的光响应性退化

摘要 基于二维 (2D) 范德华 (vdW) 材料的光电探测器由于响应时间快、光响应性好和光暗电流比高而备受关注。由于相互关联的面内 (IP) 和面外 (OOP) 偏振，α-In2Se3 是用于光电探测器的有趣的 2D vdW 材料之一。已经证明，偏振可用于调节基于 α-In2Se3 纳米薄片的光电探测器的光响应性。此外，当基于 α-In2Se3 纳米薄片的光电探测器处于辐射环境时，域演化可能与光响应性下降有关。然而，电离和位移损伤对辐射粒子引起的光响应性的影响仍不清楚。在本文中，用于光电探测器的基于 α-In2Se3 的晶体管暴露在 60Co γ 射线环境中以引起光响应性下降，所有通道宽度约为 95-100 μm，用于观察显着的辐射效应。为了研究基于 α-In2Se3 的晶体管的固有光响应性退化，使用 405 nm 激光作为光源来测量光响应性。随着辐照剂量的增加，器件的光响应性显着降低。除此之外，随着总剂量的增加，暗电流和Se原子的比率降低。电离效应和位移效应引起的畴演化促进了光响应性的退化，可能表现出复杂的耦合辐射效应。在总剂量为 1 Mrad (Si) 60Co γ 射线后，当输入光功率密度约为 454 μW/cm2 时，光电探测器仍可用于探测具有约 107 A/W 的高光响应度的光。我们的结果可能会促进基于 2D vdW 材料的光电探测器中辐射效应的研究。