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Reliability of 4-Mbit Toggle MRAM

Published online by Cambridge University Press:  01 February 2011

Johan Åkerman
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Philip Brown
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Brian Butcher
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Renu Dave
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Mark DeHerrera
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Mark Durlam
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Brad Engel
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Earl Fuchs
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Mark Griswold
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Greg Grynkewich
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Jason Janesky
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
John Martin
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Joseph Nahas
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Srinivas Pietambaram
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Nick Rizzo
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Jon Slaughter
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Ken Smith
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Ji-Jun Sun
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
Saied Tehrani
Affiliation:
Freescale Semiconductor, 1300 N Alma School Rd, Chandler, 85224, AZ
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Abstract

A 4Mb magnetoresistive random access memory (MRAM) with a novel magnetic free layer and toggle switching mode is presented. The new free layer uses a balanced synthetic-antiferromagnet trilayer structure and a novel write pulse sequence to provide robust switching performance with immunity from ½-select disturbs. This new mode greatly improves the switching performance of the MRAM as compared to conventional MRAM. The intrinsic reliability of the magnetoresistive tunnel junction (MTJ) and the metal interconnect system of MRAM are two other areas of great interest due to the new materials involved. Time dependent dielectric breakdown (TDDB) and resistance drift were the two main failure mechanisms identified for intrinsic memory bit reliability. Results indicated that a lifetime over 10 years is achievable under the operating conditions. Finally data retention is demonstrated over times that are orders of magnitude longer than 10 years.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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References

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