PHASE TRANSITION TYPE OPTICAL DISK AND PRODUCTION OF PHASE TRANSITION TYPE OPTICAL DISK

摘要

PROBLEM TO BE SOLVED: To decrease the volume changes when a recording layer is heated for overwriting and to prevent exothermic reaction accompanied by crystallization of the recording layer, by forming the recording layer by sputtering a target comprising Ge, Sb and Te in a mixture atmosphere of Ar gas, nitrogen gas and oxygen gas. ;SOLUTION: A substrate 1 is set in a vacuum film forming device, and a first dielectric layer 2, a phase transition type recording layer 3, a second dielectric layer 4 and a reflection layer 5 are successively formed. The recording layer 3 is formed by sputtering a target comprising Ge-Sb-Te in an atmosphere of Ar and a mixture gas of nitrogen and oxygen. The proportion of the pressure of the mixture gas to the Ar gas is 0.3 to 5%. Thereby, decrease in the reproducing amplitude due to the movement of substances which constitute the recording layer 3 during repeated rewriting can be suppressed, and rewriting performances can be improved when a conventional material and device are used.;COPYRIGHT: (C)1998,JPO