Ligand-Driven Grain Engineering of High Mobility Two-Dimensional Perovskite Thin-Film Transistors
Ligand-Driven Grain Engineering of High Mobility Two-Dimensional Perovskite Thin-Film Transistors
复制标题
高迁移率二维超导薄膜晶体管的配体驱动晶粒工程
DOI：
10.1021/jacs.1c06337
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发表时间：
2021-09-13
影响因子：
15
通讯作者：
Dou, Letian
中科院分区：
文献类型：
--
作者：
Liang, Aihui;Gao, Yao;Dou, Letian
控制晶粒生长对于最大化多晶薄膜电子器件的电荷载流子输运是非常重要的。卤化物钙钛矿材料的薄膜生长已经通过许多方法进行了控制，包括溶剂工程，组合物工程和后处理工艺。然而，这些方法中没有一种导致具有极大晶粒尺寸和高电荷载流子迁移率的大规模原子级平坦薄膜。在这里，我们展示了一种新的p-共轭配体设计方法，用于控制薄膜成核和生长动力学在二维（2D）卤化物钙钛矿。通过扩展p-共轭和增加半导体配体的平面性，成核密度可以降低超过5个数量级。结果，容易获得具有高度有序的晶体结构和极大晶粒尺寸的晶片级2D钙钛矿薄膜。我们展示了高性能场效应晶体管，空穴迁移率接近10 cm（2）V-1 s（-1），开/关电流比接近106，具有出色的稳定性和再现性。我们的建模分析进一步证实了增强的电荷传输和所观察到的迁移率的场和温度依赖性的起源，这使得在这些新生的2D半导体系统中的结构-性质关系的清晰的破译。
Controlling grain growth is of great importance in maximizing the charge carrier transport for polycrystalline thin-film electronic devices. The thin-film growth of halide perovskite materials has been manipulated via a number of approaches including solvent engineering, composition engineering, and post-treatment processes. However, none of these methods lead to large-scale atomically flat thin films with extremely large grain size and high charge carrier mobility. Here, we demonstrate a novel p-conjugated ligand design approach for controlling the thin-film nucleation and growth kinetics in two-dimensional (2D) halide perovskites. By extending the p-conjugation and increasing the planarity of the semiconducting ligand, nucleation density can be decreased by more than 5 orders of magnitude. As a result, wafer-scale 2D perovskite thin films with highly ordered crystalline structures and extremely large grain size are readily obtained. We demonstrate high-performance field-effect transistors with hole mobility approaching 10 cm(2) V-1 s(-1) with ON/OFF current ratios of similar to 106 and excellent stability and reproducibility. Our modeling analysis further confirms the origin of enhanced charge transport and field and temperature dependence of the observed mobility, which allows for clear deciphering of the structure-property relationships in these nascent 2D semiconductor systems.