Method for measuring saturation magnetization of magnetic films and multilayer stacks
US10788561B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 2018 |
| Grant date | Sep 29, 2020 |
| Priority date | — |
| Expiry date | Feb 23, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/60
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A ferromagnetic resonance (FMR) measurement method is disclosed wherein a magnetic film or stack of layers is patterned into elongated structures having a length along a long axis. A magnetic field (H) is applied in two different orientations with respect to the long axis (in-plane parallel and perpendicular to the long axis) or one orientation may be perpendicular-to-plane. In another embodiment, H is applied parallel to a first set of elongated structures with a long axis in the x-axis direction, and perpendicular to a second set of elongated structures with a long axis in the y-axis direction. From the difference in measured resonance frequency (Δfr) (for a fixed magnetic field and sweeping through a range of frequencies) or the difference in measured resonance field (ΔHr) (for a fixed microwave frequency and sweeping through a range of magnetic field amplitudes), magnetic saturation Ms is determined using formulas of demagnetizing factors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.