Sputtered multilayer films for digital magnetic recording

Abstract

Layered films of cobalt over chromium deposited by dc sputtering onto heated substrates exhibit magnetic properties suitable for digital saturation recording. A cobalt layer of a few tens of nanometers thickness deposited over a chromium layer of several hundred nanometers has coercivity between 1100 and 300 Oe and remanence-thickness product between 0.014 and 0.07 G.cm with squareness between 0.7 and 0.95. Additional alternate layers of chromium and cobalt can increase remanent flux without reduction of coercivity. Magnetic properties can be tailored to specific needs by varying layer thicknesses.