Orientation controlled sputtered CoNi/Cr recording rigid disk

Abstract

Well orientated sputtered CoNi/Cr Films For magnetic recording disks have been prepared by a new process. A shielding mask has been used to control the incident direction of the sputtered Cr atoms. In the layered Film of the 420A thick Co <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">82</inf> Ni <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">18</inf> deposited over pure Cr by OC magnetron sputtering, a high coercive Force of 1430 Oe and a high squareness ratio of 0.82 in tangential direction are achieved. These magnetic properties are not isotropic. By using the shielding mask, a magnetic easy axis has been orientated in the tangential direction to the circumference of the disk. An SEM observation shows that agglomeration of the deposits into chains occurs whose long axes are parallel to the circumferential direction of the disk. The well controlled orientation is considered to be caused by the self shadowing effect.