Study of oxygen-doped GeSbTe film and its effect as an interface layer on the recording properties in the blue wavelength

An oxygen-doped GeSbTe interface layer improves the overwriting characteris tics of the phase-change optical disk in the blue wavelength. The thermal a nd optical properties of oxygen-doped GeSbTc film and its crystal structure were investigated. Crystallization temperature and activation energy of th e amorphous Ge-Sb-Te-O films are increased with the oxygen concentration wh ile the melting point is decreased. The refractive index of the crystalline state monotonically increases with the oxygen concentration of the film. w hile its extinction coefficient monotonically decreases. In terms of the cr ystalline structure. fcc characteristic peaks disappear gradually with oxyg en concentration, and above 35 at.% of oxygen, hexagonal peaks appear.