SPUTTERING TARGET FOR FORMING PROTECTIVE FILM FOR OPTICAL DISK, AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To obtain a target capable of reducing the generation of particles at the time of film formation by sputtering and suitable for the preparation of a protective film for a dielectric for an optical disk. SOLUTION: Color control is performed so that the (a) value and the (b) value of a color-difference meter representing the color of a ZnS-SiO2 sputtering target become -2 to 0 and 0 to 6, respectively, and the control of a stoichiometric deviation from the composition of the sputtering target by the resultant color index is carried out. By this method, the generation of particles having a correlation with the color of a target can be remarkably reduced and also the uniformity of a film can be improved.