Magnetic films having a predetermined coercivity
Abstract
Abstract D R A W I N G MAGNETIC FILMS HAVING A PREDETERMINED COERCIVITY ARE FORMED BY DISPOSING A VACUUM DEPOSITED, POLYCRYSTALLINE THIN MAGNETIC FILM OF IRON, COBALT OR NICKEL IN AN OXYGEN BEARING ATMOSPHERE AND SUBSEQUENTLY ANNEALING THE MAGNETIC FILM AT A TEMPERATURE BETWEEN 50*C. AND 600*C. FOR A SUFFICIENT PERIOD, E.G. BETWEEN 10 TO 300 MINUTES, TO INCREASE THE COERCIVITY OF THE MAGNETIC FILM TO A DESIRED VALUE WITHIN A FIXED RANGE. IN A SPECIFIC INSTANCE, A MONOTONIC INCREASE FROM 38.4 OERSTEDS TO 530 OERSTEDS WAS OBSERVED IN THE COERCIVE FORCE OF 300 A. THICK IRON FILM UPON A GLASS SUBSTRATE WHEN ANNEALED FOR 130 MINUTES AT A PRESSURE OF 5X10**-5 TORR. ANNEALING OF THE MAGNETIC FILMS GENERALLY WAS FOUND TO PRODUCE ONLY A FRACTIONAL DECREASE IN THE MAGNETIZATION OF THE FILMS.
Inventors
- 👤 Donald Stanley Rodbell
- 👤 James M Lommel
Bibliographic Details
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