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


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.


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How to Cite
NULHAKIM, Lukman et al. Electrical and optical properties of Ga-doped ZnO thin films deposited by DC magnetron sputtering. Journal of Science and Applicative Technology, [S.l.], v. 4, n. 1, p. 15-20, june 2020. ISSN 2581-0545. Available at: <https://journal.itera.ac.id/index.php/jsat/article/view/264>. Date accessed: 22 jan. 2021. doi: https://doi.org/10.35472/jsat.v4i1.264.