Wide Bandgap Zinc Oxide Thin Films Prepared by RF Magnetron Sputtering at Room Temperature

Abstract

Room temperature RF magnetron sputtering deposition of Zinc Oxide thin films on a glass substrate was carried out by varying deposition parameters such as sputtering pressure, target-to-substrate distance, and RF power. The as-deposited film at 75 W, sputtering pressure of 9.8 mbar and a target-to-substrate distance of 104 mm has showed a band gap of 3.31 eV and RMS surface roughness of 7.1 nm. Electrical characterization and UV–VIS results reveal its high resistivity (1.3 × 10⁷ Ω-cm) and transparency >86% in a wide optical range (494–1100 nm). This film could be used as a buffer layer of CIS solar cells, SAW, and other similar thin film devices over a flexible substrate.

KEYWORDS:

• Flexible substrate
• SAW
• Solar cell
• Sputtering
• ZnO

ACKNOWLEDGEMENT

The research work was carried out at Centre of Excellence in NanoTechnology (CEN) at IIT Bombay under INUP (Indian Nanoelectronics Users' Programme) which is an initiative by the Ministry of Electronics and Information Technology (MeitY), Government of India.

Additional information

Notes on contributors

Gaurav Saxena

Gaurav Saxena received the BTech degree in electronics and telecommunication engineering from Uttar Pradesh Technical University, Lucknow, India in 2007. He obtained the MTech and PhD from National Institute of Technology Hamirpur and Indian Institute of Technology Guwahati in 2009 and 2015, respectively, in the area of VLSI design and semiconductor devices. He is currently working as an Assistant Professor in the Department of Electronics and Communication Engineering, Indian Institute of Information Technology Senapati, Manipur, India. His research focuses on the semiconductor devices and sensors.

Roy Paily

Roy Paily received the BTech degree in electronics and communication engineering from College of Engineering, Trivandrum, India in 1990. He obtained the MTech and PhD from Indian Institute of Technology Kanpur and Indian Institute of Technology Madras in 1996 and 2004 respectively, in the area of semiconductor Devices. Presently he is working as a Professor in the Department of Electronics and Electrical Engineering, Indian Institute of Technology Guwahati. His research interests are VLSI devices/circuits and MEMS. Email: [email protected]