Multi-probe ferromagnetic resonance (FMR) apparatus for wafer level characterization of magnetic films
US11237240B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 2020 |
| Grant date | Feb 1, 2022 |
| Priority date | — |
| Expiry date | Aug 24, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/345
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A ferromagnetic resonance (FMR) measurement system is disclosed with a plurality of “m” RF probes and one or more magnetic assemblies to enable a perpendicular-to-plane or in-plane magnetic field (Hap) to be applied simultaneously with a sequence of microwave frequencies (fR) at a plurality of “m” test locations on a magnetic film formed on a whole wafer under test (WUT). A FMR condition occurs in the magnetic film (stack of unpatterned layers or patterned structure) for each pair of (Hap, fR) values. RF input signals are distributed to the RF probes using RF power distribution or routing devices. RF output signals are transmitted through or reflected from the magnetic film to a plurality of “n” RF diodes where 1≤n≤m, and converted to voltage signals which a controller uses to determine effective anisotropy field, linewidth, damping coefficient, and/or inhomogeneous broadening at the predetermined test locations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.