CoCrPtTa single layer perpendicular magnetic recording media with carbon underlayer

Sputter-deposited amorphous carbon was applied as an underlayer for a Co73C r18Pt6Ta3 Single layer perpendicular magnetic recording medium. It is shown that the amorphous carbon underlayer can control the Co [001] preferred or ientation of the Co73Cr18Pt6Ta3 magnetic recording layer and that the micro crystalline structure, magnetic properties, and read-write characteristics of Co73Cr18Pt6Ta3 media are greatly dependent on the carbon underlayer thic kness. By x-ray diffraction experiments and transmission electron microscop y observations, it was confirmed that the distribution of the c-axis orient ation of Co grains becomes broader in the direction perpendicular to the fi lm surface with increasing carbon underlayer thickness. Furthermore, the Co 73Cr18Pt6Ta3 medium with a thick carbon underlayer indicated a relatively h igh perpendicular coercivity of 2800 Oe and an excellent signal to noise ra tio in read-write characteristics. (C) 2000 American Institute of Physics. [S0021-8979(00)03324-7].