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:
Jan. 21, 2014
Filed:
Jun. 21, 2011
Ioan Tudosa, Fremont, CA (US);
Yuchen Zhou, San Jose, CA (US);
Jing Zhang, Los Altos, CA (US);
Rajiv Yadav Ranjan, San Jose, CA (US);
Yiming Huai, Pleasanton, CA (US);
Ioan Tudosa, Fremont, CA (US);
Yuchen Zhou, San Jose, CA (US);
Jing Zhang, Los Altos, CA (US);
Rajiv Yadav Ranjan, San Jose, CA (US);
Yiming Huai, Pleasanton, CA (US);
Avalanche Technology Inc., Fremont, CA (US);
Abstract
High-frequency resonance method is used to measure magnetic parameters of magnetic thin film stacks that show magnetoresistance including MTJs and giant magnetoresistance spin valves. The thin film sample can be unpatterned. Probe tips are electrically connected to the surface of the film (or alternatively one probe tip can be punched into the thin film stack) and voltage measurements are taken while injecting high frequency oscillating current between them to cause a change in electrical resistance when one of the layers in the magnetic film stack changes direction. A measured resonance curve can be determined from voltages at different current frequencies. The damping, related to the width of the resonance curve peak, is determined through curve fitting. In embodiments of the invention a variable magnetic field is also applied to vary the resonance frequency and extract the magnetic anisotropy and/or magnetic saturation of the magnetic layers.