2D transition metal dichalcogenides and their heterojunctions have demonstrated great potentialities for applications in optoelectronics, and rare‐earth doping has proven an effective way for achieving high performance. Here, 2D WS2 and Er3+ in situ doped WSe2 are prepared by the chemical vapor deposition method. Thicknesses and atomic structures of the prepared WS2 and WSe2 are characterized by atomic force microscopy and transmission electron microscope, while qualities of the membranes are characterized by photoluminescence spectroscopy and Raman spectroscopy, respectively. The 13.7 and 15.8 at% of Er3+ doping concentration in WSe2 are examined by energy dispersive spectroscopy and X‐ray photoelectron spectroscopy, respectively. Performances of photodetectors based on the WSe2 and Er3+ doped WSe2 membranes are characterized individually. A microregion fixed‐point transfer technique is used to transfer the monolayer WS2 onto the Er‐doped monolayer WSe2 to form vertical van der Waals heterojunctions. Excellent performances are measured from the monolayer WS2/WSe2(Er3+) heterojunction photodetector with a photoresponsivity (Rλ) of up to 40.5 A W−1 and external quantum efficiency (EQE) of 8793%. The results prove the effectiveness of Er3+ in situ doping in WS2/WSe2(Er) heterojunctions for high‐performance photodetectors.

中文翻译：

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用于高性能光电探测器的 2D WS2/WSe2(Er) 异质结

二维过渡金属二硫属化物及其异质结在光电子学中显示出巨大的应用潜力，而稀土掺杂已被证明是实现高性能的有效方法。这里，2D WS2和厄尔3+原位掺杂WSe2采用化学气相沉积法制备。制备的WS的厚度和原子结构2和硒化钨2通过原子力显微镜和透射电子显微镜表征，而膜的质量分别通过光致发光光谱和拉曼光谱表征。 Er 的 13.7 和 15.8 at%3+WSe 掺杂浓度2分别通过能量色散光谱和X射线光电子能谱进行检测。基于WSe的光电探测器的性能2和厄尔3+掺杂WSe2膜是单独表征的。使用微区域定点转移技术来转移单层 WS2到掺铒单层WSe上2形成垂直范德华异质结。优异的性能是通过单层 WS 来衡量的2/硒化钨2（呃3+）具有光响应性（Rλ) 高达 40.5 AW−1外量子效率（EQE）为8793%。结果证明Er的有效性3+WS 中的原位掺杂2/硒化钨2用于高性能光电探测器的（Er）异质结。