10:30 〜 10:45
▼ [12a-S302-7] Fabrication of MTJs using D03-FeAlSi epitaxial film
キーワード：TMR effect, MTJ, Sendust
To improve the sensitivity of Magnetic tunnel junction (MTJ) sensors, there is a need for soft magnetic materials that have both a high tunnel magnetoresistance (TMR) ratio and soft magnetic properties. This study focused on Fe85Al5.4Si9.6 (sendust, hereinafter referred to as FeAlSi), which exhibits excellent soft magnetic properties in the bulk state. Our previous study succeeded in fabricating D03-FeAlSi thin film on MgO substrate, which shows good soft magnetic properties [1]. Since the crystal structure is similar to that of Fe electrodes, a high TMR ratio is also expected due to Δ1 coherent tunneling through the MgO barrier layer [2]. This study aims to fabricate a single crystal MTJ device using FeAlSi thin film as a free layer and evaluate its TMR effect.
From the X-ray diffraction results of the FeAlSi thin film prepared under the optimum conditions, four symmetric peaks of FeAlSi(111) were observed, confirming the successful preparation of D03-FeAlSi epitaxial thin film. From the magnetization curve of the D03-FeAlSi epitaxial thin film, it was observed that the soft magnetic property (Hk=0.3Oe) was better than that of the free layer materials such as NiFe in the previous study. In addition, the TMR effect was successfully observed (58.4%, R.T.), and a relatively small reversal field (=2.47 Oe) reflecting the soft magnetic properties of the FeAlSi free layer was also confirmed. In conclusion, the prepared FeAlSi epitaxial thin film is a promising material for high-sensitivity MTJ sensors.
From the X-ray diffraction results of the FeAlSi thin film prepared under the optimum conditions, four symmetric peaks of FeAlSi(111) were observed, confirming the successful preparation of D03-FeAlSi epitaxial thin film. From the magnetization curve of the D03-FeAlSi epitaxial thin film, it was observed that the soft magnetic property (Hk=0.3Oe) was better than that of the free layer materials such as NiFe in the previous study. In addition, the TMR effect was successfully observed (58.4%, R.T.), and a relatively small reversal field (=2.47 Oe) reflecting the soft magnetic properties of the FeAlSi free layer was also confirmed. In conclusion, the prepared FeAlSi epitaxial thin film is a promising material for high-sensitivity MTJ sensors.