[9p-PB1-1~80] 10 Spintronics and Magnetics (Poster)

▲ [9p-PB1-64] High TMR Ratio and High Signal Output of Array TMR Sensor Deposited on Chemical-Mechanical Polishing Cu Buffer Layer

〇Kousuke Fujiwara¹, Mahiro Sato¹, Sabri Cakir¹, Seiji Kumagai¹, Mikihiko Oogane², Yasuo Ando² (1.Spin Sensing Factory Corp., 2.Tohoku Univ.)

Keywords:sensor, bio magnetic field, magnetic tunnel junction

Medical applications of biomagnetic field measurement using TMR sensor are expected. In order to reduce 1/f noise, the TMR sensors are electrically connected in an array, but the signal output decreases due to the parasitic resistance. In this study, we fabricated TMR sensors on chemical-mechanical polished Cu layer. Comparison of TMR ratios with and without Cu layer, a TMR ratio as high as about 1.5 times was obtained with Cu. It is considered that the TMR ratio was improved due to the reduction in the parasitic resistance of the bottom layer of the sensor. As a result of this increase in TMR ratio, we succeeded in improving the signal output in the sensor using Cu.