Effects of Zn doped MoO3 nanocomposite interlayer on electrical and surface chemical state properties of Ni/Cr/n-GaN Schottky junction

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 2024-10, Vol.308, p.117602, Article 117602
• Main Authors: Manjunath, V., Kunapalli, Chaitanya Kumar, Vani, M., Jaya Madhuri, R., Ragab, Sameh Abdallah, Karim, Mohammad Rezaul, Nanda Kumar Reddy, N., Munirathnam, K., Sekhar Reddy, P.R., Siddarapu, Himagirish Kumar, Ko, Tae J., Prakash, Nunna Guru, Rosaiah, P.
• Format: Article
• Language: English
• Subjects: Chemically synthesised Zn:MoO3 nanocomposite; DC/RF sputtering; Microstructural and electrical properties; n-type GaN
• ISSN: 0921-5107
• DOI: 10.1016/j.mseb.2024.117602

•Morphological, structural and Chemical properties of Ni/Cr/Zn:MoO3/n-GaN/Al/Ti MIS junction are investigated by XRD and XPS.•Ni/Cr/Zn:MoO3/n-GaN MIS junction electrical properties exhibited excellent rectifying nature.•Higher Φb and low reverse leakage current is achieved for the MIS junction compared to the Schottky junction.•The cross-sectional SEM image clearly displays a smooth and uniform Ni/Cr/Zn:MoO3/n-GaN coating. Furthermore, the AFM analysis confirms that the surface morphology of the Ni/Cr contacts on n-type GaN is significantly smooth.•The interface state density of the MIS junction was lesser than the Schottky junction. A nanocomposite insulating layer of Zn:MoO3 was prepared for a Ni/Cr/Zn:MoO3/n-GaN MIS junction, wherein the structural and chemical states, and electrical properties were analysed through using various techniques including XRD, SEM, AFM, XPS, I-V and C-V measurements at room temperature. Using XPS spectra and survey scans, clear peaks were observed with increasing counts, indicating the presence of all elements in the fabricated MIS junction. This was further verified by GIXRD analysis, ensuring comprehensive validation of the elemental composition and structural integrity of the materials used. The electrical characterization indicated that the fabricated MIS Schottky junctions exhibited appropriate rectifying behaviour with lower leakage currents. Moreover, the series resistance (RS) was determined for both the Ni/Cr/n-GaN SJ and the Ni/Cr/Zn-MoO3/n-GaN MIS junctions. Interestingly, the MIS junction exhibited a reasonable Schottky barrier height (Φb) compared to the SJ. The MIS junction yielded 0.87eV and 1.12 eV from I-V and C-V measurements at room temperature, respectively. Whereas the SJ junction yielded 0.72 eV from I-V and 0.89 eV from C-V measurements at room temperature. This suggests that the presence of the interlayer in the MIS junction significantly influenced the Φb. Utilizing Cheung’s, Norde, Hernord and surface potential analysis methods, the Φb, ideality factor (n), and RS values were estimated. Further analysis indicated a lower interface state density (NSS) for the MIS junction compared to the SJ, indicating that the Zn:MoO3 insulator layer played a crucial role in reducing NSS. Experimental observations suggested that while SE governed the reverse current in SJ, both PF and SE were leading current conduction mechanisms in different bias regions of the MIS junction. Overall, the findings supported the suit