Thin films of beta-AgGaO2, were fabricated on (0001)-Al2O3 substrates by radio frequency magnetron sputtering. beta-AgGaO2 is a ternary oxide semiconductor possessing a wurtzite-derived beta-NaFaO(2)-type structure. The effects of changing experimental parameters including sputtering atmosphere, pressure and substrate temperature were investigated. The effects of the sputtering conditions on the composition, phase, morphology and optical transmission of the films were determined. A highly crystalline beta-AgGaO2 film was obtained by deposition at 200 degrees C under a 15% O-2 atmosphere at a pressure of 0.5 Pa. This film was (001)-oriented, similar to wurtzite-type phases. The energy band gap of beta-AgGaO2 was determined to be 2.2 eV from its photocurrent spectrum. (C) 2013 Elsevier B.V. All rights reserved.