A surface modification (expansion) has been observed in amorphous antimony based chalcogenide (Sb2S3) thin films when a pulsed electron beam is focused onto the surface of the film at accelerating voltages between 15 and 30 kV. The dependence of pattern heights and width on parameters such as exposure time, beam current and accelerating voltage have also been studied. The modification of the film surface involves lateral and vertical expanded which is typically in the micrometre and submicrometre range. This phenomenon can be explained in terms of electrostatic force. (c) 2004 Elsevier B.V. All rights reserved.