Amorphous gadolinium-iron layers for bubble memories - made by vapour deposition and with very low coercive force

摘要

Amorphous layers contg. Gd and Fe are made by vapour deposition, in an appts. using a vacuum of min. 10-8 torr and then a partial pressure (Pa) of a reactive gas during vapour deposition of Gd and Fe at specific speeds on a substrate. The speeds and Pa are pref. matched to produce a desired collapse field strength, saturation magnetisation, and coercive force. Only Gd and Fe may be deposited, or a non-magnetic metal, esp. Pd, may also be included, esp. using max. 10 atom % Pd in the Fe + Pd. Reactive gas is pref. O2, H2, or N2. Used for the mfr. of bubble memories. Gd-FE-(Pd) layers obtd. have good magnetic properties, esp. a very low coercive force.