Performance of write-line inserted magnetic tunneling junction for low-write-current magnetic random access memory cell

Abstract

We have developed a write-line-inserted magnetic tunnelingjunction(MTJ) (WLIM) for use in low-write-current magnetoresistance random access memory (MRAM). The write current of the WLIM was reduced to 0.98 mA and its thermal stability factor was 85 for a 0.32 × 0.48 μ m 2 MTJ. We evaluated the switching property of the WLIM in an external magnetic field ( H sw ̱ ext ) and an internal magnetic field ( H sw ̱ int ) . We found that H sw ̱ ext was larger than H sw ̱ int when the aspect ratio of the MTJs was less than 1.5. Furthermore, we obtained a high write-current magnetic-field efficiency of 13.0 Oe ∕ mA when the aspect ratio of the MTJs was low. These properties mean that the WLIM structure has advantages for use in low-write-current MRAM.