TMR device with low magnetorestriction free layer
US8472151B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 2012 |
| Grant date | Jun 25, 2013 |
| Priority date | — |
| Expiry date | Apr 11, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1114
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A high performance TMR sensor is fabricated by employing a free layer with a trilayer configurations represented by FeCo/CoFeB/CoB, FeCo/CoB/CoFeB, FeCo/CoFe/CoB, or FeCo/FeB/CoB may also be employed. Alternatively, CoNiFeB or CoNiFeBM formed by co-sputtering CoB with CoNiFe or CoNiFeM, respectively, where M is V, Ti, Zr, Nb, Hf, Ta, or Mo may be included in a composite free layer or as a single free layer in the case of CoNiFeBM. A 15 to 30% in improvement in TMR ratio over a conventional CoFe/NiFe free layer is achieved while maintaining low Hc and RA<3 ohm-um2. In bilayer or trilayer embodiments, magnetostriction (λ) between −5×10−6 and 5×10−6 is achieved by combining CoB (−λ) and one or more layers having a positive λ.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.