Method of forming thin oxidation layer by cluster ion beam
US6800565B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 2003 |
| Grant date | Oct 5, 2004 |
| Priority date | — |
| Expiry date | Jan 24, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/84
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of forming a thin-film magnetic element, such as a TMR element or a spin valve element, on a substrate wherein at least a surface portion of a nonmagnetic metal layer is oxidized by cluster ion beam (CIB) oxidation. Specifically, the method comprises depositing a first magnetic layer on a substrate, then depositing a nonmagnetic metal layer on the first magnetic layer. At least a top surface of the nonmagnetic layer is oxidized by CIB oxidation. In one embodiment, only a top surface portion is oxidized such that a nano-oxide layer (NOL) is formed on a nonmagnetic conductive layer. In another embodiment, the nonmagnetic metal layer is oxidized throughout it's thickness such that the layer is converted to a nonmagnetic insulating film. After oxidation, a second magnetic layer is deposited on the oxidized layer. Oxidizing by cluster ion beam oxidation advantageously comprises mixing a pressurized inert carrier gas with oxygen gas to form a gas mixture and passing the gas mixture into a low pressure vacuum to produce a supersonic gas jet, whereby expansion occurs in the jet to cause formation of clusters of inert gas and oxygen atoms and molecules. The clusters are then ionize…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.