Preparation and short-wavelength optical storage properties of Ge-Te alloy phase change thin film

The preparation method and short-wavelength optical storage properties of Ge-Te alloy phase change thin film are reported. The film was prepared by rf-sputtering technology. The deposited films were amorphous. The crystallization temperature was 190 degrees Celsius. The optical spectrum measurements showed that the reflectivity of the crystalline state film was rather high -- about 50% at 780 nm, which may be suitable for CD-E storage medium. A static optical recording tester with a focused Argon laser beam (514.5 nm) irradiating on the films was used to evaluate the optical storage performance of the films. The results showed that a rather large reflectivity contrast (larger than 15%) can be obtained at low power beam.