Hyun Changbae, Kim Jong Hun, Lee Jong-Young, Lee Gwan-Hyoung, Kim Kwang S
Department of Physics, Pohang University of Science and Technology Pohang 37673 Republic of Korea
Department of Materials Science and Engineering, Seoul National University Seoul 08826 Republic of Korea
RSC Adv. 2020 Jan 2;10(1):350-355. doi: 10.1039/c9ra08029e. eCollection 2019 Dec 20.
Black phosphorus (BP) is a promising two-dimensional (2D) material for future electronic devices due to its unique properties of high carrier mobility and large band gap tunability. However, thinner crystalline BP is more readily degraded under ambient conditions. For BP-based electronic devices, degradation of the exfoliated BP is a key issue. However, the nanometer scale study of BP degradation is rare so far. Herein, we report an atomically resolved degradation process of the BP surface using atomic force microscopy under temperature- and humidity-controlled environments. The atomically resolved crystal surface of BP deteriorated due to surface etching after cleavage, and showed monolayer etching. The etching process is accelerated by applying a bias voltage to BP a conductive tip. After the voltage-assisted BP etching, the BP etching product shows crystalline BP confirmed by Raman spectroscopy and atomic force microscopy. Our atomic scale study of BP will be useful for the future 2D-based electronic devices to overcome conventional silicon-based electronic devices.
黑磷（BP）因其具有高载流子迁移率和大带隙可调性等独特性质，是未来电子器件中一种很有前景的二维（2D）材料。然而，更薄的结晶态BP在环境条件下更容易降解。对于基于BP的电子器件而言，剥落的BP的降解是一个关键问题。然而，迄今为止，对BP降解的纳米尺度研究很少。在此，我们报告了在温度和湿度可控的环境下，使用原子力显微镜对BP表面进行原子分辨的降解过程。BP的原子分辨晶体表面在解理后由于表面蚀刻而恶化，并呈现出单层蚀刻。通过向BP施加偏置电压到导电尖端，蚀刻过程会加速。在电压辅助BP蚀刻之后，BP蚀刻产物经拉曼光谱和原子力显微镜证实为结晶态BP。我们对BP的原子尺度研究将有助于未来基于二维材料的电子器件克服传统的硅基电子器件。
