Magnetic recording disk, method of the magnetic recording disk and magnetic recording apparatus

Abstract

A magnetic recording medium includes a non-magnetic substrate, an inorganic compound layer that is formed on the substrate and which contains a crystalline first oxide and an amorphous second oxide, and a magnetic layer that is formed on the inorganic compound layer. The crystalline first oxide comprises at least one oxide selected from cobalt oxide, chromium oxide, iron oxide and nickel oxide. The amorphous second oxide comprises at least one oxide selected from silicon oxide, aluminum oxide, titanium oxide, tantalum oxide and zinc oxide. The amorphous second oxide is present at a grain boundary of crystal grains of the first oxide.

What is claimed is:  
     
         1 . A magnetic recording medium comprising 
 a nonmagnetic substrate,    an inorganic compound layer including a crystalline first oxide having a hexagonal structure and an amorphous second oxide, said inorganic compound layer being formed on the substrate, and    a magnetic layer formed on said inorganic compound layer,    wherein said crystalline first oxide comprises at least one oxide selected from the group consisting of cobalt oxide, chromium oxide, iron oxide and nickel oxide, 
 said amorphous second oxide comprises at least one oxide selected from the group consisting of silicon oxide, aluminum oxide, titanium oxide, tantalum oxide and zinc oxide, and  
 said amorphous second oxide is present at a grain boundary of crystal grains of said first oxide.  
   
     
     
         2 . The magnetic recording medium according to  claim 1 , wherein a grain size of crystal grains constituting the first oxide is 10 nm or less, and a spacing between crystal grains constituting the first oxide is 0.5 nm-1.0 nm.  
     
     
         3 . The magnetic recording medium according to  claim 1 , wherein an average grain size of crystal grains constituting the magnetic layer is 10 nm or less, and a standard deviations σ of the crystal grain size is 2 nm or less.