[17a-M_374-1~12] 10.3 スピンデバイス・磁気メモリ・ストレージ技術

11:00 〜 11:15奨励賞エントリー英語発表

[17a-M_374-9] Tunnel-magnetoresistance sensor using amorphous Co–Zr–Ta-based free layer

〇(M2)Tomoki Nagareda¹, Mikihiko Oogane^1,2, Takafumi Nakano^1,3 (1.Tohoku Univ., 2.Tohoku Univ CSIS, 3.Tohoku Univ Green X-Tech)

キーワード：

Spintronics、Magnetic sensor、Soft magnetic

Tunnel magneto-resistance (TMR) sensor is one of the promising bio-magnetic sensor due to its low power consumption, small size and high sensitivity. The sensitivity of TMR sensors is defined as TMR ratio divided 2H_k in which H_k is anisotropy field of free layer. Currently the sensitivity of 115%/Oe is achieved by using amorphous CoFeSiB for free layers. Generally, TMR ratio increases with increasing post-deposition annealing temperatures. However, the annealing temperature is limited to around 330 °C due to low thermal stability of CoFeSiB. In this work, we fabricated TMR sensors using amorphous Co–Zr–Ta alloys, which exhibit superior thermal stability even in µm films, and investigated their magnetoresistance properties.