Short-Wavelength Recording Properties of TeO_x Thin Films

We prepare TeO_x thin films by vacuum evaporation of TeO₂ powder. It is found that the as-deposited TeO_x films can represent a two-component system comprising crystalline tellurium particles dispersed in an amorphous TeO₂ matrix. Results of the static recording test show that the TeO_x films have good writing sensitivity for short-wavelength laser beam (514.5 nm). Primary results of the dynamic recording test at 514.5 nm are also reported. The carrier-to-noise ratio of 30 dB is obtained for the disk using a TeO_x film as the recording medium. Atomic force microscopy is used to study the microstructure of recorded marks. Micro-area morphology images show that the marks are mechanically deformed, and depressions and bulges have been imaged in the recorded marks, resulting in the scattering of the reading laser beam. The analytical results of transmission electron microscopy show that there is not obvious difference between the phase states of the tellurium particles before and after laser irradiation. Recording mechanism of the TeO_x thin films are discussed based on the experimental results.