A novel SPRAM (SPin-transfer torque RAM) with a synthetic ferrimagnetic free layer for higher immunity to read disturbance and reducing write-current dispersion

被引：23

作者：

Miura, K. ^{[1
]}

Kawahara, I. ^{[2
]}

Takemura, R. ^{[2
]}

Hayakawa, J. ^{[1
,3
]}

Ikeda, S. ^{[3
]}

Sasaki, R. ^{[3
]}

Takahashi, H. ^{[1
,2
]}

Matsuoka, H. ^{[1
]}

Ohno, H. ^{[3
]}

机构：

[1] Hitachi Ltd, Adv Res Lab, Kokubunji, Tokyo 1858601, Japan

[2] Hitachi Ltd, Cent Res Lab, Kokubunji, Tokyo 1858601, Japan

[3] Tohoku Univ, Lab Nanoelect & Spintron, Res Inst Elect Commun, Aoba Ku, Sendai, Miyagi 9808577, Japan

来源：

2007 SYMPOSIUM ON VLSI TECHNOLOGY, DIGEST OF TECHNICAL PAPERS | 2007年

关键词：

D O I：

10.1109/VLSIT.2007.4339706

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

A novel SPRAM (SPin-transfer torque RAM) consisting of MgO-barrier-based magnetic tunnel junctions (MTJs) with a synthetic ferrimagnetic (SyF) structure in a free layer was demonstrated for both higher immunity to read disturbance and a sufficient margin between the read and write currents. Since magnetization of the free layer becomes stable against thermal fluctuation with increasing thermal-stability factor E/k(B)T, the SyF free layer of the MTJs realized a magnetic information retention of over 10 years due to its high E/k(B)T of 67. Furthermore, it was found that the SyF free layer has an advantage of reducing dispersion of write-current density J(c), which is necessary for securing an adequate margin between the read and write currents.

引用

页码：234 / +

页数：2

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