Mtj pillar having temperature-independent delta
AssigneeInternational Business Machines Corporation
InventorsDaniel Worledge, Guohan Hu
Life of this patent
Estimating the term…
Abstract
A magnetoresistive random access memory (MRAM) including spin-transfer torque (STT) MRAM is provided that has enhanced data retention. The enhanced data retention is provided by constructing a MTJ pillar having a temperature-independent Delta, where Delta is Delta=Eb/kt, wherein Eb is the activation energy, k is the Boltzmann's constant, and T is the absolute temperature. Notably, the present application provides a way for EB to actually increase with temperature, which can cancel the effect of the term KT, resulting in a temperature independent Delta.
Claims20
A method comprising:
- reading data stored in a magnetoresistive random access memory (MRAM) comprising a magnetic tunnel junction (MTJ) pillar having a temperature-independent delta and comprising a tunnel barrier layer located between a magnetic reference layer and a magnetic free layer, wherein the magnetic free layer is composed of a material whose magnetization increases with increasing temperature and the magnetic free layer provides at least a 10 fold increase in data retention as compared to an equivalent MTJ pillar that lacks the magnetic free layer whose magnetization increases with increasing temperature.
A method comprising:
- reading data stored in a magnetoresistive random access memory (MRAM) comprising a magnetic tunnel junction (MTJ) pillar having a temperature-independent delta and comprising a tunnel barrier layer located between a magnetic reference layer and a multilayered magnetic free layer structure that includes a first magnetic free layer and a second magnetic free layer separated by a non-magnetic layer, wherein the second magnetic free layer is composed of a material whose magnetization increases with increasing temperature and the second magnetic free layer provides at least a 10 fold increase in data retention as compared to an equivalent MTJ pillar that lacks the second magnetic free layer whose magnetization increases with increasing temperature.
Dependencies are inferred from the claim text.