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:
Oct. 07, 2003
Filed:
Mar. 08, 2000
Rolf Allenspach, Adliswil, CH;
Jean Fompeyrine, Waedenswil, CH;
Eric Fullerton, Morgan Hill, CA (US);
Jean Pierre Locquet, Horgen, BE;
Timothy Moran, Springfield, CA (US);
Maria Seo, Lausanne, CH;
International Business Machines Corporation, Armonk, NY (US);
Abstract
The present invention concerns at least an antiferromagnetic layer, which is in direct contact with a ferromagnetic layer for inducing an exchange bias in the ferromagnetic layer. Thus, the ferromagnetic layer is pinned by the antiferromagnetic layer, also referred to as the pinning layer. The antiferromagnetic or pinning layer comprises a compound from the group of orthoferrites, which show a variety of advantages. For example, these antiferromagnets can have a Néel temperature T ranging from at least 623 K to 740 K depending on the compounds, and they can display a weak ferromagnetic moment. Therefore, a magnetic device comprising the mentioned structure can be used properly in an environment of a high operating temperature. The compound can be described by the formula RFe TM O with R a rare earth element or Yttrium, and TM a transition metal which can be one element of the groups IB to VIII. The compound can be also doped by an element S being an element with another valence, such as Barium, Nickel, Strontium, Calcium, Potassium, or Sodium in compound R S FeO .