Jin Weifeng, Yang Xinyang
Key Laboratory of Optoelectronic Technology and Systems (Ministry of Education), College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China.
Phys Chem Chem Phys. 2023 Oct 11;25(39):26455-26460. doi: 10.1039/d3cp03341d.
Field-effect transistors (FETs) based on semiconductor nanowires (NWs) have been extensively investigated and used for constructing novel nanoelectronic and optoelectronic devices in the past two decades. High electric field transport characteristics in FETs are of significance in both physics and applications. However, some specific physics phenomena at high electric field, such as drift velocity saturation, have rarely been reported in semiconductor NW FETs. In this work, the high electric field transport characteristics in FETs based on CdSe NWs were investigated. In the output characteristic curves, the current saturation phenomenon at high electric field caused by drift velocity saturation was observed. Typical values of saturation drift velocity and low electric field mobility in CdSe NW FETs were obtained. The low electric field mobility is in the range of 265.2 to 388.0 cm V s. The saturation drift velocity is in the range of 5.1 × 10 to 7.0 × 10 cm s and decreases monotonically with the increase of charge density, indicating that the electron-phonon scattering mechanism dominates at high electric field. Saturation drift velocity is an important figure-of-merit which characterizes the high electric field transport performance in FETs. As far as we know, this is the first experimental report on saturation drift velocity in CdSe NW FETs, which may provide valuable guidance for the design of nanoelectronic and optoelectronic devices based on CdSe NWs in the future.
在过去二十年中，基于半导体纳米线（NWs）的场效应晶体管（FETs）得到了广泛研究，并被用于构建新型纳米电子和光电器件。FETs中的高电场输运特性在物理和应用方面都具有重要意义。然而，在半导体NW FETs中，一些高电场下的特定物理现象，如漂移速度饱和，却鲜有报道。在这项工作中，研究了基于CdSe NWs的FETs的高电场输运特性。在输出特性曲线中，观察到了由漂移速度饱和引起的高电场下的电流饱和现象。获得了CdSe NW FETs中饱和漂移速度和低电场迁移率的典型值。低电场迁移率在265.2至388.0 cm² V⁻¹ s⁻¹范围内。饱和漂移速度在5.1×10⁷至7.0×10⁷ cm s⁻¹范围内，并随着电荷密度的增加而单调下降，这表明在高电场下电子 - 声子散射机制占主导地位。饱和漂移速度是表征FETs中高电场输运性能的一个重要品质因数。据我们所知，这是关于CdSe NW FETs中饱和漂移速度的首次实验报告，这可能为未来基于CdSe NWs的纳米电子和光电器件的设计提供有价值的指导。
