Magnetic memory device

Abstract

A method of manufacturing a magnetic memory device includes forming a stacked structure including a magnetic element, forming a metal film which covers the stacked structure, and forming a protective insulating film formed of a metallic oxide by oxidizing the metal film. A metal element contained in the metallic oxide is selected from yttrium (Y), aluminum (Al), magnesium (Mg), calcium (Ca), zirconium (Zr) and hafnium (Hf).

What is claimed is: 
     
         1 . A method of manufacturing a magnetic memory device, the method comprising:
 forming a stacked structure including a magnetic element;   forming a metal film which covers the stacked structure; and   forming a protective insulating film formed of a metallic oxide by oxidizing the metal film, wherein   a metal element contained in the metallic oxide is selected from yttrium (Y), aluminum (Al), magnesium (Mg), calcium (Ca), zirconium (Zr) and hafnium (Hf).   
     
     
         2 . The method of  claim 1 , wherein a linear coefficient of thermal expansion of the metallic oxide is greater than 5×10 −6 /K. 
     
     
         3 . The method of  claim 1 , wherein a linear coefficient of thermal expansion of the metallic oxide is greater than 7×10 −6 /K. 
     
     
         4 . The method of  claim 1 , wherein the magnetic element contains at least one of cobalt (Co), iron (Fe), boron (B) and magnesium (Mg). 
     
     
         5 . The method of  claim 1 , wherein the magnetic element includes a first magnetic layer, a second magnetic layer, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer. 
     
     
         6 . A method of manufacturing a magnetic memory device, the method comprising:
 forming a stacked structure including a magnetic element;   forming a metal film which covers the stacked structure; and   forming a protective insulating film formed of a metallic oxide by oxidizing the metal film, wherein   a linear coefficient of thermal expansion of the metallic oxide is greater than 5×10 −6 /K.   
     
     
         7 . The method of  claim 6 , wherein the linear coefficient of thermal expansion of the metallic oxide is greater than 7×10 −6 /K. 
     
     
         8 . The method of  claim 6 , wherein the magnetic element contains at least one of cobalt (Co), iron (Fe), boron (B) and magnesium (Mg). 
     
     
         9 . The method of  claim 6 , wherein the magnetic element includes a first magnetic layer, a second magnetic layer, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer.