| 摘要 |
PURPOSE:To prevent peeling and to obtain stable film quality by setting the internal stress of an SiN protective film formed by a prescribed method and an etching rate by boiling of pure water at prescribed values. CONSTITUTION:An SiN film 14 is formed as the substrate protective film on a polycarbonate substrate 12 and a TbFeCoTi film 16 is formed as a recording film thereon. The SiN protective film 18, an AlTi reflection film 20 and a protective resin film 22 are formed thereon. The SiN film 14 is formed by subjecting an Si target to reactive sputtering in a gaseous mixture composed of gaseous Ar and gaseous nitrogen. The internal stress of this SiN film 14 is <=10<10> dyn/cm<2> and the etching rate by the boiling of the pure water is 1300Angstrom /Hr. Since the internal stress of the film 14 is small, the film does not peel in spite of swelling of the substrate 12 by moisture absorption. |
