Growth of oxide exchange bias layers
AssigneeThe Regents of the University of California
InventorsAlison Chaiken, Richard P. Michel
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Abstract
An oxide (NiO, CoO, NiCoO) antiferromagnetic exchange bias layer produced by ion beam sputtering of an oxide target in pure argon (Ar) sputtering gas, with no oxygen gas introduced into the system. Antiferromagnetic oxide layers are used, for example, in magnetoresistive readback heads to shift the hysteresis loops of ferromagnetic films away from the zero field axis. For example, NiO exchange bia layers have been fabricated using ion beam sputtering of an NiO target using Ar ions, with the substrate temperature at 200.degree. C., the ion beam voltage at 1000V and the beam current at 20 mA, with a deposition rate of about 0.2 .ANG./sec. The resulting NiO film was amorphous.
Claims14
In a process for forming an oxide exchange bias layer, the improvement comprising:
- depositing the oxide layer by ion beam sputtering of a metal oxide target in an atmosphere consisting of an inert sputtering gas,
- whereby ion beam sputtering is carried out in the absence of oxygen gas.
A process for forming antiferromagnetic NiO layers for use in magnetoresistive readback heads, magnetic random access memories, magnetic field sensors, etc., comprising:
- providing a deposition chamber;
- providing an NiO target;
- providing a substrate;
- directing an ion beam onto the NiO target in the presence of argon gas and absence of oxygen gas causing sputter deposition of the NiO of the target onto the substrate.
Dependencies are inferred from the claim text.