AN ANALYSIS ON MICROSTRUCTURAL GROWTH-PROCESS IN ELECTROLESS CONIREP FILMS FOR PERPENDICULAR MAGNETIC RECORDING MEDIA

The segregated microstructure and the growth process of electroless CoNiReP films were examined using selective chemical etching and heat-treatment methods. The segregated condition in the film changes with an increase in the film thickness up to ca. 200 nm, while it keeps a constant nature with a further increase in the film thickness of up to 2 mum. In the region of thickness over 200 nm, the film consists of high-crystallized particles with 20 nm diam segregating in the nonmagnetic region with low crystallinity. Such a segregation is confirmed to occur from the nucleation stage before forming a continuous film, and the segregated structure is stable with heat-treatment up to 500-degrees-C.