Abstract
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.
Original language | English |
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Article number | 8995801 |
Pages (from-to) | 995-1000 |
Number of pages | 6 |
Journal | IEEE Transactions on Electron Devices |
Volume | 67 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2020 Mar |
Keywords
- Interfacial anisotropy type magnetic tunnel junction (MTJ)
- quad interface
- spin-transfer-torque magnetoresistive random access memory (STT-MRAM)
- switching efficiency
- thermal stability factor
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering