Title :
Transport and Magnetic Properties of CPP-GMR Sensor With CoMnSi Heusler Alloy
Author :
Mizuno, Tomohito ; Tsuchiya, Yoshihiro ; Machita, Takahiko ; Hara, Shinji ; Miyauchi, Daisuke ; Shimazawa, Kouji ; Chou, Tsutomu ; Noguchi, Kiyoshi ; Tagami, Katsumichi
Author_Institution :
Adv. Head Dev. Group, TDK Corp., Nagano
Abstract :
We investigated structural and magnetic properties of CoMnSi (CMS) Heusler alloy films and giant magneto-resistance (GMR) ratio of current-perpendicular-to-plane (CPP) GMR sensor elements. The films were deposited with magnetron sputtering method and annealed at 673 K and 773 K. The CMS films were identified as B2 structure by using X-ray diffraction and the magnetization of the films were evaluated as 0.95 T. We fabricated the CPP-GMR sensors varying the composition of the CMS films, Co48 Mn21 Si31 (at. %) as Si-rich CMS and Co51Mn25Si24 (at. %) as CMS-ref, having a FeCo layer between the CMS and Cu spacer. It was found that the element with Si-rich CMS exhibited higher GMR ratio of 9.0% than that with CMS-ref. Our calculations indicate that larger spin polarization of contact region between the CMS film and the FeCo film relates to larger GMR ratio.
Keywords :
X-ray diffraction; cobalt alloys; giant magnetoresistance; magnetic sensors; magnetic thin film devices; magnetisation; magnetoresistive devices; manganese alloys; silicon alloys; spin polarised transport; sputter deposition; Co45Mn21Si31; Cu; FeCo; Heusler alloy films; X-ray diffraction; current-perpendicular-to-plane GMR sensor elements; giant magnetoresistance ratio; magnetization; magnetron sputtering method; spin polarization; temperature 673 K; temperature 773 K; Current-perpendicular-to-plane (CPP); Heusler alloys; giant magneto-resistance (GMR); magnetic recording;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2008.2001655
