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:
Jun. 30, 2020
Filed:
Jun. 07, 2017
Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu, TW;
Huanlong Liu, Sunnyvale, CA (US);
Guenole Jan, San Jose, CA (US);
Yuan-Jen Lee, Fremont, CA (US);
Jian Zhu, San Jose, CA (US);
Po-Kang Wang, Los Altos, CA (US);
TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu, TW;
Abstract
Circuits and methods for programming a MTJ stack of an MRAM cell minimizes a ferromagnetic free layer or pinned layer polarization reversal due to back-hopping. The programming begins by applying a first segment of the segment of the write pulse at a first write voltage level for a first time period to program the MTJ stack. A second segment of the segment of the write pulse at a second write voltage level that is less than the first write voltage level is applied to the magnetic tunnel junction stack for a second time period to correct the polarization of the MTJ when the MTJ stack has reversed polarization during the first time period. The second segment of the segment of the write pulse may be a ramp, or multiple ramps, or have a quiescent period between it and the first segment of the write pulse.