Effects of argon pressure on the properties of ZnO:Ga thin films deposited by DC magnetron sputtering

• Main Authors: Marwoto, Putut, Fatiatun, Sulhadi, Sugianto, Aryanto, Didik
• Format: Conference Proceeding
• Language: English
• Subjects: Argon; Energy gap; Gallium; Gas pressure; Glass substrates; Grain; Magnetic properties; Magnetron sputtering; Optical properties; Photovoltaic cells; Pressure effects; Thin films; Zinc oxide; Zinc oxides
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/1.4943711

Gallium (Ga)-doped zinc oxide (ZnO:Ga) thin films were deposited on corning glass substrates by homemade DC magnetron sputtering. Effects of argon gas pressure on the structural and optical properties of ZnO:Ga thin films were investigated by XRD, SEM and UV-Vis spectroscopy. The argon gas pressure was adjusted at 450, 500 and 550 mtorr. All the films exhibit a strong (002) peak and a weak (004) peaks. The XRD pattern demonstrated that crystallinity of the film improved with increasing of the argon pressure. ZnO:Ga thin films deposited have polycrystalline structure. It was shown that the argon pressure has a great influence on ZnO:Ga film surface structures. The grain size of the films was increased with the increases of argon pressure. The grains shape of the film change from an equiaxed rough grain to a longish grain with the argon pressure. The average of transmittance of the films is about 80% in the visible range. It is shown that the argon pressure has no effect significantly on optical bandgap of ZnO:Ga, but in general it can be explained that increasing of the argon pressure can reduce the bandgap. The optical bandgap of ZnO:Ga thin films in the range of 3.25 - 3.3 eV.