Padma R, Lee Gilho, Kang Jeong Seob, Jun Seong Chan
School of Mechanical Engineering, Yonsei University, Seoul 120-749, South Korea.
School of Mechanical Engineering, Yonsei University, Seoul 120-749, South Korea.
J Colloid Interface Sci. 2019 Aug 15;550:48-56. doi: 10.1016/j.jcis.2019.04.061. Epub 2019 Apr 20.
In this study, Au/MoS/n-GaAs heterojunction is fabricated with single MoS layer and its structural, chemical and electrical parameters are investigated using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and measurement of current-voltage (I-V) characteristics at room temperature. XRD and XPS analysis results confirm the formation of MoS layer on the n-GaAs surface. The electrical properties of the Au/MoS/n-GaAs heterojunction are compared with those of the Au/n-GaAs Schottky junction. Interestingly, the heterojunction possesses a higher barrier height, lower leakage current and higher rectification ratio, in comparison with the Schottky junction. The shunt resistance (R) and series resistance (R) are also assessed for both the junctions. Moreover, the ideality factor (n), barrier height (Φ) and series resistance (R) are evaluated using Norde, Cheung's and surface potential (Ψ-V) plots and the results are well-matched. Furthermore, the current transport mechanism is analyzed based on the forward bias I-V data. Lastly, the Poole-Frenkel emission conduction mechanism is employed to control the reverse bias I-V behavior of both Au/n-GaAs Schottky junction and Au/MoS/n-GaAs heterojunction. The results demonstrate that the Au/MoS/n-GaAs heterojunction fabricated using a simple technique is suitable for high-quality electronic and optoelectronic device applications.
在本研究中，制备了具有单MoS层的Au/MoS/n-GaAs异质结，并使用X射线衍射（XRD）、X射线光电子能谱（XPS）以及在室温下测量电流-电压（I-V）特性来研究其结构、化学和电学参数。XRD和XPS分析结果证实了在n-GaAs表面形成了MoS层。将Au/MoS/n-GaAs异质结的电学性质与Au/n-GaAs肖特基结的电学性质进行了比较。有趣的是，与肖特基结相比，该异质结具有更高的势垒高度、更低的漏电流和更高的整流比。还对两种结的并联电阻（R）和串联电阻（R）进行了评估。此外，使用诺德（Norde）、张（Cheung）的方法以及表面势（Ψ-V）图评估了理想因子（n）、势垒高度（Φ）和串联电阻（R），结果吻合良好。此外，基于正向偏置I-V数据对电流传输机制进行了分析。最后，采用普尔-弗伦克尔（Poole-Frenkel）发射传导机制来控制Au/n-GaAs肖特基结和Au/MoS/n-GaAs异质结的反向偏置I-V行为。结果表明，采用简单技术制备的Au/MoS/n-GaAs异质结适用于高质量的电子和光电器件应用。
