Illumination of amorphous As2S3 film by ultraviolet light with an overall light intensity on the sample surface of around 10 W cm(-2) leads to extensive film oxidation. After 2 min of illumination most of As2S3 film of an original thickness at around 0.425 mu m was converted into a cubic form of As2O3-arsenolite. A considerable amount of arsenolite microcrystals were found at a height of around 2 mu m and more which indicated a growth of As2O3 microcrystalline particles from the vapor phase. (C) 2012 Elsevier B.V. All rights reserved.