Structural, chemical, and electrical parameters of Au/MoS 2 /n-GaAs metal/2D/3D hybrid heterojunction

• Published in: Journal of colloid and interface science 2019-08, Vol.550, p.48
• Main Authors: Padma, R, Lee, Gilho, Kang, Jeong Seob, Jun, Seong Chan
• Format: Article
• Language: English
• ISSN: 1095-7103
• DOI: 10.1016/j.jcis.2019.04.061

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.