High recording density magnetic media with square b-h loop
Abstract
Abstract A MAAGNETIC RECORDING MEDIUM AND A METHOD OF PRODUCING IT WHICH PERMITS THE PRODUCTION OF A MAGNETIC RECORDING MEDIUM HAVING A HIGH INTRINSIC COERCIVITY GREATER THAN 300 OERSTEDS AND AN 0.95 SQUARE B-H HYSTERESIS LOOP PERMITTING HIGH SWITCHING SPEEDS AND HIGH DENSITY RECORDING. THE MAGNETIC RECORDING MEDIUM COMPRISES AN ALUMINUM ALLOY DISC SUBSTRATE COVERED BY XINC AND NICKEL LAYERS, OVERLAID BY A GOLD FILM AND THIN-FILM COBALT MAGNETIC LAYER. THE FABRICATION PROCESS INVOLVES ELECTROLESS DEPOSITION OF THIN-FILM LAYERS OF ZINC AND NICKEL ON THE SUBSTRATE, THEN THE DEPOSITION OF A ONE-HALF MICRO-INCH GOLD LAYER CONVERTED BY A COBBALT PHOSPHORUS THIN-FILM LAYER. THE METHOD PROVIDES FOR TAILORING OF THE VALUE OF COERCIVITY INDEPENDENT OF THE THICKNESS OF THE MAGNNETIC FILM LAYER. D R A W I N G
Inventors
- 👤 E Stone
- 👤 P Patel
Bibliographic Details
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