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. 30, 2013
Filed:
Oct. 10, 2007
Tai Min, San Jose, CA (US);
Po Kang Wang, San Jose, CA (US);
Tai Min, San Jose, CA (US);
Po Kang Wang, San Jose, CA (US);
MagIC Technologies, Inc., Milpitas, CA (US);
Abstract
A CPP MTJ MRAM unit cell utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The strength of the switching field, Hof the cell is controlled by the magnetic anisotropy of the cell which, in turn, is controlled by a combination of the shape anisotropy and the stress and magnetostriction of the cell free layer. The coefficient of magnetostriction of the free layer can be adjusted by methods such as adding Nb or Hf to alloys of Ni, Fe, Co and B or by forming the free layer as a lamination of layers having different values of their coefficients of magnetostriction. Thus, by tuning the coefficient of magnetostriction of the cell free layer it is possible to produce a switching field of sufficient magnitude to render the cell thermally stable while maintaining a desirable switching current.