Magneto-resistance effect device, and magnetic recorder

Abstract

According to one embodiment, a magneto-resistance effect device includes: a multilayer structure having a cap layer; a magnetization pinned layer; a magnetization free layer provided between the cap layer and the magnetization pinned layer; a spacer layer provided between the magnetization pinned layer and the magnetization free layer; a function layer which is provided in the magnetization pinned layer, between the magnetization pinned layer and the spacer layer, between the spacer layer and the magnetization free layer, in the magnetization free layer, or between the magnetization free layer and the cap layer, the function layer having oxide containing at least one element selected from Zn, In, Sn and Cd, and at least one element selected from Fe, Co and Ni; and a pair of electrodes for applying a current perpendicularly to a film plane of the multilayer structure.

1 . A magneto-resistance effect device comprising:
 a multilayer structure having a cap layer;   a magnetization pinned layer;   a magnetization free layer provided between the cap layer and the magnetization pinned layer;   a spacer layer provided between the magnetization pinned layer and the magnetization free layer;   a function layer which is provided in the magnetization pinned layer, between the magnetization pinned layer and the spacer layer, between the spacer layer and the magnetization free layer, in the magnetization free layer, or between the magnetization free layer and the cap layer, the function layer having oxide containing at least one element selected from Zn, In, Sn and Cd, and at least one element selected from Fe, Co and Ni; and   a pair of electrodes applying a current perpendicularly to a film plane of the laminate.   
     
     
         2 . The device according to  claim 1 , wherein
 resistivity of the function layer is not higher than 5×10 4  μΩcm.   
     
     
         3 . The device according to  claim 1 , wherein
 film thickness of the function layer is not smaller than 1 nm and not larger than 10 nm.   
     
     
         4 . The device according to  claim 1 , wherein
 the product of a sectional area perpendicular to a stacking direction of the multilayer structure and resistance obtained from the pair of electrodes when a current is applied perpendicularly to the film plane of the multilayer structure is not larger than 1 Ωμm 2 .   
     
     
         5 . The device according to  claim 1 , wherein
 the spacer layer comprises:   an insulating layer containing oxygen or nitrogen; and   current paths which punched though the insulating layer in a direction perpendicular to a film plane of the spacer layer so that a current can be applied in the spacer layer.   
     
     
         6 . The device according to  claim 1 , wherein
 the function layer further contains at least one element selected from Al, B, Ga, C, Si, Ge and Sn.   
     
     
         7 . The device according to  claim 1 , wherein
 the spacer layer contains any one of Cu, Au and Ag.   
     
     
         8 . A magnetic recorder comprising:
 a magnetic recording medium;   a magnetic recording head comprising a magneto-resistance effect device comprising:
 a multilayer structure having a cap layer; 
 a magnetization pinned layer; 
 a magnetization free layer provided between the cap layer and the magnetization pinned layer; 
 a spacer layer provided between the magnetization pinned layer and the magnetization free layer; 
 a function layer which is provided in the magnetization pinned layer, between the magnetization pinned layer and the spacer layer, between the spacer layer and the magnetization free layer, in the magnetization free layer, or between the magnetization free layer and the cap layer, the function layer having oxide containing at least one element selected from Zn, In, Sn and Cd, and at least one element selected from Fe, Co and Ni; and 
 a pair of electrodes for applying a current perpendicularly to a film plane of the multilayer structure; and 
   a signal processing portion which performs signal writing/reading into/from the magnetic recording medium by using the magnetic recording head.