Metal migration and surface modification have been observed in metal-doped amorphous arsenic and antimony-based chalcogenide systems such as As2Se3 and Sb2S3 Under the irradiation of an electron beam. Surface expansion of the order of 5-35% of the film thickness has been observed by applying 5-30 kV electron accelerating voltages. This electron beam induced surface modification has been employed to produce submicron and nanometre dimensional patterns which will have applications in single stage processing of X-ray masks fabricated on an X-ray transparent silicon nitride (Si3N4) membrane. Masks with a silver deficient trough-like structure have been obtained at lower accelerating voltages (5-10 kV). Silver-rich protruding structures were obtained at higher accelerating voltages (15-30 kV). These two types of masks exhibit a different X-ray absorption behaviour by comparison with the regions unexposed to the electron beam. (c) 2004 Elsevier B.V. All rights reserved.