The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 04, 2006
Filed:
Jul. 28, 2004
Tai Min, San Jose, CA (US);
Yimin Guo, San Jose, CA (US);
Pokang Wang, San Jose, CA (US);
Headway Technologies, Inc., Milpitas, CA (US);
Abstract
An MTJ including the free layer and reference layer have a vortex magnetization state that is formed with a clockwise or counterclockwise rotation. The MTJ has a low aspect ratio elliptical shape and the magnetic layers have a dopant that is one of C, N, B, Zr, Ta, Pt, Nb, or Hf to facilitate the flux closure configuration. The vortex magnetization is induced by applying a reverse magnetic field in a direction opposite to the remnant magnetization in a magnetic layer. An anti-ferromagnetic layer is set in an AFM phase after the vortex state is induced in the adjacent reference layer. Switching the vortex state in the free layer involves applying a first field in a first direction to break the vortex and then applying a smaller second field in a reverse direction to a critical point where a vortex of opposite spin is induced.