Magnetic recording medium, method for manufacturing recording medium and magnetic recording apparatus

Abstract

A magnetic recording layer is formed on an under-layer comprising a Cu crystalline grain layer and a deposited nitrogen atom layer on the Cu crystalline grain layer surface. Then the magnetic recording layer comprising very small average grain diameter and sharp grain diameter distribution is obtained. The magnetic recording medium comprising the magnetic recording layer shows excellent signal to noise ratio at high density recording.

1 . A method for producing magnetic recording medium, comprising: 
 a process for forming a grain diameter control layer comprising Cu crystalline grains on a substrate;    a process for forming a deposited layer of nitrogen atoms depositing nitrogen on the grain diameter control under-layer surface; and    a process for forming a magnetic recording-layer on the substrate having the nitrogen-layer deposited grain diameter control under-layer.    
     
     
         2 . The method for producing magnetic recording medium as set forth in  claim 1 , 
 wherein the nitrogen atoms are deposited in an average areal density range from 1×10 13  atoms/cm 2  to 1×10 15  atoms/cm 2  on the grain diameter control under-layer surface at the process for forming a deposited layer of nitrogen atoms.    
     
     
         3 . The method for producing magnetic recording medium as set forth in  claim 1 , 
 wherein the grain diameter control under-layer comprising 50 nm or larger Cu crystalline grains is formed at the process for forming a grain diameter control under-layer, and the nitrogen atoms are deposited on the grain diameter control under-layer surface at the process for forming a deposited layer of nitrogen atoms.    
     
     
         4 . The method for producing magnetic recording medium as set forth in  claim 1 , 
 wherein the Cu crystalline grains of the grain diameter control under-layer orienting (100) planes of the crystalline grains parallel to the substrate surface is formed at the process for forming a grain diameter control layer.    
     
     
         5 . The method for producing magnetic recording medium as set forth in  claim 4 , 
 wherein the magnetic crystalline grains are arranged essentially in a form of tetragonal lattice structure in the magnetic recording-layer plane at the process of forming a magnetic recording-layer.    
     
     
         6 . The method for producing magnetic recording medium as set forth in  claim 1 , 
 wherein the magnetic crystalline grains in the magnetic recording-layer are formed in an average areal density range from 1×10 12  grains/cm 2  to 8×10 12  grains/cm 2  at the process for forming a magnetic recording-layer.