AgGaSe2 thin films were prepared on quartz glass by using an evaporation method at room temperature. Some of the samples were annealed at temperatures from 100 to 600 degrees C in a nitrogen atmosphere for 10 min. X-ray diffraction showed that single phase AgGaSe2 could be grown at an annealing temperature of 600 degrees C. From transmittance and reflectance spectra, an absorption coefficient of 105 cm(-1) around bandgap region and bandgap energy of 1.787 eV could be obtained. (c) 2005 Elsevier B.V. All rights reserved.