The underlayer film treatment effect on TbCo film properties in optical disk memory structure

A large perpendicular magnetic anisotropy constant (K
u
) has been achieved for the TbCo film by introducing a sputter-etching treatment on the dielectric underlayer film before the deposition of the TbCo film. The K
u
value exceeded 2 × 10
⁶
erg/cm
³
by sputter-etching treatment at power densities of 70 mW/cm
²
or greater. It has also been clarified that sputter-etching treatment contributed to achieving high stability of multilayer media life. The effects of the treatment process are described experimentally.