Electron-induced effects in Ge-Se films studied by Kelvin probe force microscopy

The processes of surface relief formation on Ge_xSe_100-x films under their point irradiation by an electron beam have been studied. Electron-induced effects in Ge_xSe_100-x films are interpreted in framework of a two-layer charge model. The distribution of the surface potential in the locally irradiated regions of the Ge_xSe_100-x film have been established using the Kelvin probe force microscopy (KFPM). The KPFM measurements reveal that the driving force behind mass transfer is not localized charge in the film itself, but rather the gradient of the electric field created by the charge. The potential distribution derived from the measured KPFM illustrates the distribution of gradient of the electric field. We find that the direction of the field gradient sets the direction of mass transfer during point exposure with electron beam.