Yao Jiandong, Zheng Zhaoqiang, Yang Guowei
State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering , Sun Yat-sen University , Guangzhou 510275 , Guangdong , P. R. China.
ACS Appl Mater Interfaces. 2018 Nov 7;10(44):38166-38172. doi: 10.1021/acsami.8b10396. Epub 2018 Oct 23.
In this work, a p-type 2D SnS nanofilm containing both laterally and vertically aligned components was successfully deposited on an n-type Si substrate through pulsed-laser deposition. Energy band analysis demonstrates a typical type-II band alignment between SnS and Si, which is beneficial to the separation of photogenerated carriers. The as-fabricated p-SnS/n-Si heterojunction photodetector exhibits multicolor photoresponse from ultraviolet to near-infrared (370-1064 nm). Importantly, the device manifests a high responsivity of 273 A/W, a large external quantum efficiency of 4.2 × 10%, and an outstanding detectivity of 7× 10 Jones (1 Jones = 1 cm Hz W), which far outperforms state-of-the-art 2D/3D heterojunction photodetectors incorporating either laterally or vertically aligned 2D layered materials (2DLMs). The splendid performance is ascribed to lateral SnS's dangling-bond-free interface induced efficient carrier separation, vertical SnS's high-speed carrier transport, and collision ionization induced carrier multiplication. In sum, the current work depicts a unique landscape for revolutionary design and advancement of 2DLM-based heterojunction photodetectors.
在这项工作中，通过脉冲激光沉积成功地在n型硅衬底上沉积了一种包含横向和纵向排列成分的p型二维硫化锡纳米薄膜。能带分析表明硫化锡和硅之间存在典型的II型能带排列，这有利于光生载流子的分离。所制备的p-SnS/n-Si异质结光电探测器表现出从紫外到近红外（370 - 1064 nm）的多色光响应。重要的是，该器件表现出273 A/W的高响应度、4.2×10%的大外部量子效率以及7×10琼斯（1琼斯 = 1 cm Hz W）的出色探测率，这远远超过了包含横向或纵向排列的二维层状材料（2DLMs）的最先进的二维/三维异质结光电探测器。出色的性能归因于横向硫化锡无悬空键界面诱导的高效载流子分离、纵向硫化锡的高速载流子传输以及碰撞电离诱导的载流子倍增。总之，当前的工作描绘了基于二维层状材料的异质结光电探测器的革命性设计和发展的独特前景。
