Magnetoresistance effect device

Abstract

A magnetoresistance effect device including a multilayer structure having a pair of ferromagnetic layers and a barrier layer positioned between them, wherein at least one ferromagnetic layer has at least the part contacting the barrier layer made amorphous and the barrier layer is an MgO layer having a highly oriented texture structure.

1 . A magnetoresistance effect device including a multilayer structure comprised of a pair of ferromagnetic layers and a barrier layer positioned between them, wherein 
 at least a part of at least one of said ferromagnetic layers contacting said barrier layer is amorphous, and    said barrier layer is an MgO layer having a single crystal structure.    
     
     
         2 . A magnetoresistance effect device including a multilayer structure comprised of a pair of ferromagnetic layers and a barrier layer positioned between them, wherein 
 at least a part of at least one of said ferromagnetic layers contacting said barrier layer is amorphous, and    said barrier layer is an MgO layer having a highly oriented fiber-texture structure.    
     
     
         3 . The magnetoresistance effect device as set forth in  claim 1 , wherein said MgO layer is a single crystal layer formed by a sputtering method.  
     
     
         4 . The magnetoresistance effect device as set forth in  claim 2 , wherein said MgO layer is a highly oriented fiber-texture layer formed by a sputtering method.  
     
     
         5 . The magnetoresistance effect device as set forth in  claim 3 , wherein said MgO layer is a single crystal layer formed using an MgO target and a sputtering method.  
     
     
         6 . The magnetoresistance effect device as set forth in  claim 4 , wherein said MgO layer is a a highly oriented fiber-texture layer formed using an MgO target and a sputtering method.  
     
     
         7 . The magnetoresistance effect device as set forth in  claim 1 , wherein said ferromagnetic layers are CoFeB layers.  
     
     
         8 . The magnetoresistance effect device as set forth in  claim 2 , wherein said ferromagnetic layers are CoFeB layers.  
     
     
         9 . A magnetoresistance effect device comprising: 
 a barrier layer having fiber-texture with a crystal, and a first and second ferromagnetic layers positioned at both sides of said barrier layer.    
     
     
         10 . The magnetoresistance effect device as set forth in  claim 9 , wherein said barrier layer includes Mg an O.  
     
     
         11 . The magnetoresistance effect device as set forth in  claim 10 , wherein both or either of said first and second ferromagnetic layers includes CoFeB.