Electrical and optical properties of Ga-doped ZnO thin films deposited by DC magnetron sputtering

Lukman Nulhakim (Engineering Physics Department, Institut Teknologi Sumatera, Indonesia)
Monna Rozana (Research Unit for Clean Technology, Indonesian Institute of Sciences, Indonesia)
Brian Yuliarto (Engineering Physics Department, Institut Teknologi Bandung, Indonesia)
Hisao Makino (Electronic and Photonic System Engineering Department, Kochi University of Technology, Japan)

Journal of Science and Applicative Technology
Vol 4 No 1 (2020): Journal of Science and Applicative Technology June Chapter

The electrical and optical properties of Ga-doped ZnO (GZO) thin film prepared by direct current (dc) magnetron sputtering were investigated. The GZO thin film was deposited on a glass substrate at a substrate temperature (Ts) of room temperature (RT), 150 °C, and 200 °C using DC power of 100 W and an Ar gas flow rate of 450 sccm. The thickness of films was maintained at about 200 nm by controlling the deposition rate of about 12.5 nm/minute. The result showed that the electrical properties improved with increasing Ts. The films deposited at Ts of 200 °C showed the lowest resistivity, highest hall mobility, and carrier concentration compared to other Ts. The average transmittance of the films in the visible range (380-750 nm) was approximately 86.04%. The value of the optical band gap (Eg) was approximately 3.8 eV. The results suggested that GZO films deposited by DC magnetron sputtering at Ts of 200 °C can be applied to transparent conducting oxide (TCO) as an electrode in optoelectronic applications such as solar cells, LEDs and display technology.