TY - JOUR
T1 - Novel Quad-Interface MTJ Technology and its First Demonstration with High Thermal Stability Factor and Switching Efficiency for STT-MRAM beyond 2X nm
AU - Nishioka, K.
AU - Sato, H.
AU - Endoh, T.
AU - Honjo, H.
AU - Ikeda, S.
AU - Watanabe, T.
AU - Miura, S.
AU - Inoue, H.
AU - Tanigawa, T.
AU - Noguchi, Y.
AU - Yasuhira, M.
N1 - Funding Information:
This work was supported in part by the Center for Science and Innovation in Spintronics (CIES) Consortium, in part by the CIES's Industrial Affiliation on Spin-Transfer- Torque Magnetoresistive Random Access Memory (STT-MRAM) Program, in part by the Japan Science and Technology Agency-Program on Open Innovation Platform with Enterprises, Research Institute and Academia (JST-OPERA) Programunder Grant JPMJOP1611, and in part by the Japan Science and Technology Agency-Accelerated Innovation Research Initiative Turning Top Science and Ideas into High-Impact Values (JST-ACCEL) Program under Grant JPMJAC1301.
Funding Information:
Manuscript received October 31, 2019; revised December 12, 2019; accepted January 8, 2020. Date of publication February 12, 2020; date of current version February 26, 2020. This work was supported in part by the Center for Science and Innovation in Spintronics (CIES) Consortium, in part by the CIES’s Industrial Affiliation on Spin-Transfer-Torque Magnetoresistive Random Access Memory (STT-MRAM) Program, in part by the Japan Science and Technology Agency-Program on Open Innovation Platform with Enterprises, Research Institute and Academia (JST-OPERA) Program under Grant JPMJOP1611, and in part by the Japan Science and Technology Agency-Accelerated Innovation Research Initiative Turning Top Science and Ideas into High-Impact Values (JST-ACCEL) Program under Grant JPMJAC1301. This article is an enhanced version of a conference paper presented at the 2019 Symposium on VLSI Technology, Kyoto, Japan. The review of this article was arranged by Editor K. Uchida. (Corresponding author: T. Endoh.) K. Nishioka, H. Honjo, T. Watanabe, S. Miura, H. Inoue, T. Tanigawa, Y. Noguchi, and M. Yasuhira are with the Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai 980-8572, Japan.
Publisher Copyright:
© 1963-2012 IEEE.
PY - 2020/3
Y1 - 2020/3
N2 - We have proposed a novel quad-interface magnetic tunnel junction (MTJ) technology which brings forth an increase of both thermal stability factor Δ and switching efficiency defined as the ratio of Δ to intrinsic critical current IC0 ( Δ /IC0 ) by a factor of 1.5-2 compared with the conventional double-interface MTJ technology. The free layer of the developed quad interface consists of bottom-MgO/FL1/middle-MgO/FL2/top-MgO stack structure. We successfully fabricated the quad-interface MTJ using a 300-mm process based on a novel low-damage integration process including physical vapor deposition (PVD), reactive ion etching (RIE), and so on. By developing the quad-interface MTJ, we have achieved about two times larger Δ and Δ /IC0 at the same time. Moreover, we have achieved about two times larger tunnel magnetoresistance (TMR) ratio at the same resistance area (RA) product by developing the FL1, bottom-MgO, and middle-MgO. The developed quad-interface MTJ technology considered as post-double-interface MTJ technology will become an essential technology for the scaling of the spin-transfer-torque magnetoresistive random access memory (STT-MRAM) beyond 20 nm.
AB - We have proposed a novel quad-interface magnetic tunnel junction (MTJ) technology which brings forth an increase of both thermal stability factor Δ and switching efficiency defined as the ratio of Δ to intrinsic critical current IC0 ( Δ /IC0 ) by a factor of 1.5-2 compared with the conventional double-interface MTJ technology. The free layer of the developed quad interface consists of bottom-MgO/FL1/middle-MgO/FL2/top-MgO stack structure. We successfully fabricated the quad-interface MTJ using a 300-mm process based on a novel low-damage integration process including physical vapor deposition (PVD), reactive ion etching (RIE), and so on. By developing the quad-interface MTJ, we have achieved about two times larger Δ and Δ /IC0 at the same time. Moreover, we have achieved about two times larger tunnel magnetoresistance (TMR) ratio at the same resistance area (RA) product by developing the FL1, bottom-MgO, and middle-MgO. The developed quad-interface MTJ technology considered as post-double-interface MTJ technology will become an essential technology for the scaling of the spin-transfer-torque magnetoresistive random access memory (STT-MRAM) beyond 20 nm.
KW - Interfacial anisotropy type magnetic tunnel junction (MTJ)
KW - quad interface
KW - spin-transfer-torque magnetoresistive random access memory (STT-MRAM)
KW - switching efficiency
KW - thermal stability factor
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U2 - 10.1109/TED.2020.2966731
DO - 10.1109/TED.2020.2966731
M3 - Article
AN - SCOPUS:85080865956
VL - 67
SP - 995
EP - 1000
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
SN - 0018-9383
IS - 3
M1 - 8995801
ER -