Gao Xiangxiang, Liu Hai-Yang, Zhang Jincheng, Zhu Jian, Chang Jingjing, Hao Yue
Advanced Interdisciplinary Research Center for Flexible Electronics, Xidian University, Xi'an 710071, China.
National Institute for Advanced Materials, School of Materials Science and Engineering, Nankai University, Tianjin 300350, China.
Micromachines (Basel). 2022 Jun 16;13(6):956. doi: 10.3390/mi13060956.
The wafer-scale fabrication of two-dimensional (2D) semiconductor thin films is the key to the preparation of large-area electronic devices. Although chemical vapor deposition (CVD) solves this problem to a certain extent, complex processes are required to realize the transfer of thin films from the growth substrate to the device substrate, not to mention its harsh reaction conditions. The solution-based synthesis and assembly of 2D semiconductors could realize the large-scale preparation of 2D semiconductor thin films economically. In this work, indium selenide (In2Se3) nanosheets with uniform sizes and thicknesses were prepared by the electrochemical intercalation of quaternary ammonium ions into bulk crystals. Layer-by-layer (LbL) assembly was used to fabricate scalable and uniform In2Se3 thin films by coordinating In2Se3 with poly(diallyldimethylammonium chloride) (PDDA). Field-effect transistors (FETs) made from a single In2Se3 flake and In2Se3 thin films showed mobilities of 12.8 cm2·V−1·s−1 and 0.4 cm2·V−1·s−1, respectively, and on/off ratios of >103. The solution self-assembled In2Se3 thin films enriches the research on wafer-scale 2D semiconductor thin films for electronics and optoelectronics and has broad prospects in high-performance and large-area flexible electronics.
二维（2D）半导体薄膜的晶圆级制造是制备大面积电子器件的关键。尽管化学气相沉积（CVD）在一定程度上解决了这个问题，但要实现薄膜从生长衬底到器件衬底的转移，需要复杂的工艺，更不用说其苛刻的反应条件了。基于溶液的二维半导体合成与组装能够经济地实现二维半导体薄膜的大规模制备。在这项工作中，通过将季铵离子电化学插入块状晶体中制备了尺寸和厚度均匀的硒化铟（In2Se3）纳米片。通过将In2Se3与聚二烯丙基二甲基氯化铵（PDDA）配位，采用逐层（LbL）组装法制备了可扩展且均匀的In2Se3薄膜。由单个In2Se3薄片和In2Se3薄膜制成的场效应晶体管（FET）的迁移率分别为12.8 cm2·V−1·s−1和0.4 cm2·V−1·s−1，开/关比大于103。溶液自组装的In2Se3薄膜丰富了用于电子和光电子领域的晶圆级二维半导体薄膜的研究，在高性能和大面积柔性电子领域具有广阔前景。
