Wu Guangjian, Wang Xudong, Chen Yan, Wu Shuaiqin, Wu Binmin, Jiang Yiyang, Shen Hong, Lin Tie, Liu Qi, Wang Xinran, Zhou Peng, Zhang Shantao, Hu Weida, Meng Xiangjian, Chu Junhao, Wang Jianlu
National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Science, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
State Key Laboratory of Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu Tian Road, Shanghai, 200083, China.
Adv Mater. 2020 Apr;32(16):e1907937. doi: 10.1002/adma.201907937. Epub 2020 Feb 27.
Doped p-n junctions are fundamental electrical components in modern electronics and optoelectronics. Due to the development of device miniaturization, the emergence of two-dimensional (2D) materials may initiate the next technological leap toward the post-Moore era owing to their unique structures and physical properties. The purpose of fabricating 2D p-n junctions has fueled many carrier-type modulation methods, such as electrostatic doping, surface modification, and element intercalation. Here, by using the nonvolatile ferroelectric field polarized in the opposite direction, efficient carrier modulation in ambipolar molybdenum telluride (MoTe ) to form a p-n homojunction at the domain wall is demonstrated. The nonvolatile MoTe p-n junction can be converted to n-p, n-n, and p-p configurations by external gate voltage pulses. Both rectifier diodes exhibited excellent rectifying characteristics with a current on/off ratio of 5 × 10 . As a photodetector/photovoltaic, the device presents responsivity of 5 A W , external quantum efficiency of 40%, specific detectivity of 3 × 10 Jones, fast response time of 30 µs, and power conversion efficiency of 2.5% without any bias or gate voltages. The MoTe p-n junction presents an obvious short-wavelength infrared photoresponse at room temperature, complementing the current infrared photodetectors with the inadequacies of complementary metal-oxide-semiconductor incompatibility and cryogenic operation temperature.
掺杂的 p-n 结是现代电子学和光电子学中的基本电子元件。由于器件小型化的发展，二维（2D）材料的出现因其独特的结构和物理性质，可能引发向摩尔时代之后的下一次技术飞跃。制造二维 p-n 结的目的推动了许多载流子类型调制方法的发展，如静电掺杂、表面改性和元素插层。在此，通过使用反向极化的非易失性铁电场，证明了在双极碲化钼（MoTe₂）中实现高效的载流子调制，从而在畴壁处形成 p-n 同质结。非易失性 MoTe₂ p-n 结可通过外部栅极电压脉冲转换为 n-p、n-n 和 p-p 配置。两个整流二极管均表现出优异的整流特性，电流开/关比为 5×10⁴。作为光电探测器/光伏器件，该器件在无任何偏置或栅极电压的情况下，响应度为 5 A/W，外部量子效率为 40%，比探测率为 3×10¹² Jones，快速响应时间为 30 µs，功率转换效率为 2.5%。MoTe₂ p-n 结在室温下呈现出明显的短波红外光响应，弥补了当前红外光电探测器在互补金属氧化物半导体不兼容性和低温工作温度方面的不足。
