Jiang Hanjun, Li Lei, Wu Yao, Duan Ruihuan, Yi Kongyang, Wu Lishu, Zhu Chao, Luo Lei, Xu Manzhang, Zheng Lu, Gan Xuetao, Zhao Wu, Wang Xuewen, Liu Zheng
Frontiers Science Center for Flexible Electronics (FSCFE) & Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, Xi'an, 710072, P. R. China.
School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
Adv Mater. 2024 Aug;36(32):e2400670. doi: 10.1002/adma.202400670. Epub 2024 Jun 10.
Two-dimensional ultrathin ferroelectrics have attracted much interest due to their potential application in high-density integration of non-volatile memory devices. Recently, 2D van der Waals ferroelectric based on interlayer translation has been reported in twisted bilayer h-BN and transition metal dichalcogenides (TMDs). However, sliding ferroelectricity is not well studied in non-twisted homo-bilayer TMD grown directly by chemical vapor deposition (CVD). In this paper, for the first time, experimental observation of a room-temperature out-of-plane ferroelectric switch in semiconducting bilayer 3R MoS synthesized by reverse-flow CVD is reported. Piezoelectric force microscopy (PFM) hysteretic loops and first principle calculations demonstrate that the ferroelectric nature and polarization switching processes are based on interlayer sliding. The vertical Au/3R MoS/Pt device exhibits a switchable diode effect. Polarization modulated Schottky barrier height and polarization coupling of interfacial deep states trapping/detrapping may serve in coordination to determine switchable diode effect. The room-temperature ferroelectricity of CVD-grown MoS will proceed with the potential wafer-scale integration of 2D TMDs in the logic circuit.
二维超薄铁电体因其在非易失性存储器件高密度集成中的潜在应用而备受关注。最近，在扭曲双层h-BN和过渡金属二硫属化物（TMDs）中报道了基于层间平移的二维范德华铁电体。然而，在通过化学气相沉积（CVD）直接生长的非扭曲同质双层TMD中，滑动铁电性尚未得到充分研究。本文首次报道了通过逆流CVD合成的半导体双层3R MoS中室温平面外铁电开关的实验观察结果。压电力显微镜（PFM）滞后回线和第一性原理计算表明，铁电性质和极化切换过程基于层间滑动。垂直Au/3R MoS/Pt器件表现出可切换的二极管效应。极化调制的肖特基势垒高度和界面深态俘获/去俘获的极化耦合可能协同作用来确定可切换的二极管效应。CVD生长的MoS的室温铁电性将推动二维TMD在逻辑电路中实现潜在的晶圆级集成。
