In this study, we investigated the behaviour of electrochemically deposited amorphous titanium oxide (TiO{sub}2) thin films towards controlled electron beam (e-beam) exposure in view of locally modifying its chemical and structural properties. Contrary to crystalline TiO{sub}2, we found amorphous TiO{sub}2 films to be significantly more sensitive to e-beam irradiation. E-beam exposure experiments were performed under scanning electron microscope conditions at 20keV with well-controlled beam current (I{sub}p), current density and exposure dose. As shown by atomic force microscopy and Micro-Raman spectroscopy, even moderate e-beam exposure immediately leads to oxide reduction and local film volume loss due to electron stimulated oxygen desorption, while exposure with I{sub}p≥lμA and J≥1A/cm{sup}2 triggers localized crystallization into anatase phase already after seconds of irradiation. The mechanisms for oxide reduction and beam heating induced crystallization are discussed, and an estimation of the temperature in the beam center indicates that crystallization occurs at less than 150°C. The well-defined volume loss upon oxygen desorption is shown to be attractive for precise topographical surface patterning in combination with e-beam lithography tools, while triggering of local structural changes within a semi-conductive amorphous matrix opens interesting possibilities for tailoring of its local electrical or catalytic properties.
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