Electron beam induced surface modification of amorphous Sb2Se3 thin film

The change in the surface morphology of amorphous Sb2Se3 thin films during the electron beam irradiation has been studied mainly by atomic force microscopy (AFM). Electron beam at accelerating voltages 30 kV is focused onto the surface of the specimens of 100-μm thickness, and then the surface morphology of each specimen has been observed by AFM in air. The modification of the film surface includes lateral and vertical resizing which is typically in the micrometer and sub-micrometer range. Protrusions above the surface as high as 90 nm are observed at 180 pA electron beam current, whilst trenches as deep as 97 nm are observed at 800 pA electron beam current (total thickness of thin film is 100 nm). The dependence of patterns characteristics on irradiation parameters such as exposure time and beam current has also been studied. Physical mechanisms for trench and mound formation are proposed.