Ferromagnetically coupled magnetic recording media

Abstract

A ferromagnetically coupled magnetic recording medium having a first ferromagnetic layer, a second ferromagnetic layer, and a ferromagnetic coupling layer to ferromagnetically couple the first ferromagnetic layer to the second ferromagnetic layer is used as stable magnetic media with high MrT in high density recording hard drives. The first ferromagnetic layer is the stabilization layer and the second ferromagnetic layer is the main recording layer. The ferromagnetic coupling layer comprises a conductive material having a thickness which produces ferromagnetic coupling between said first ferromagnetic layer and said second ferromagnetic layer via the RKKY interaction.

1 - 26 . (canceled) 
     
     
         27 . An apparatus comprising:
 a substrate;   a first ferromagnetic layer overlying said substrate;   a coupling layer overlying said first ferromagnetic layer; and   a second ferromagnetic layer overlying said ferromagnetic coupling layer,
 wherein said coupling layer provides direct exchange interaction coupling between said first ferromagnetic layer and said second ferromagnetic layer. 
   
     
     
         28 . The apparatus of  claim 27  wherein said coupling layer includes two non-magnetic spacer layers separated by a magnetic interface layer. 
     
     
         29 . The apparatus of  claim 27  wherein said coupling layer includes Co, Ni, Fe, or alloys thereof. 
     
     
         30 . The apparatus of  claim 27  wherein said coupling layer has a magnetization less than 300 emu/cm3. 
     
     
         31 . The apparatus of  claim 27  wherein said coupling layer has a magnetization less than 100 emu/cm3. 
     
     
         32 . The apparatus of  claim 27  wherein said first ferromagnetic layer and said second ferromagnetic layer are ferromagnetically coupled together. 
     
     
         33 . The apparatus of  claim 27  wherein said first ferromagnetic layer and said second ferromagnetic layer are anti-ferromagnetically coupled together. 
     
     
         34 . An apparatus comprising:
 a substrate;   a first ferromagnetic layer overlying said substrate;   a coupling layer overlying said first ferromagnetic layer, wherein said coupling layer includes a first interface layer, a second interface layer, and a spacer layer between said first interface layer and said second interface layer; and   a second ferromagnetic layer overlying said ferromagnetic coupling layer,
 wherein said coupling layer provides direct exchange interaction coupling between said first ferromagnetic layer and said second ferromagnetic layer. 
   
     
     
         35 . The apparatus of  claim 34  wherein said first interface layer or said second interface layer includes Co, Fe, or alloys thereof, and wherein further said alloys thereof include Cr, Pt, Ta, B, Mo, Pd, Cu, Au, Ti, W, Ru, Si, Ge, Nb, or Ni. 
     
     
         36 . The apparatus of  claim 34  wherein said coupling layer has a magnetization greater than 300 emu/cm3. 
     
     
         37 . The apparatus of  claim 34  wherein said coupling layer has a magnetization greater than 500 emu/cm3. 
     
     
         38 . The apparatus of  claim 34  wherein said first ferromagnetic layer and said second ferromagnetic layer are ferromagnetically coupled together. 
     
     
         39 . The apparatus of  claim 34  wherein said first ferromagnetic layer and said second ferromagnetic layer are anti-ferromagnetically coupled together. 
     
     
         40 . An apparatus comprising:
 a substrate;   a first ferromagnetic layer overlying said substrate;   a coupling layer overlying said first ferromagnetic layer, wherein magnetic grains are distributed within said coupling layer; and   a second ferromagnetic layer overlying said ferromagnetic coupling layer,
 wherein said coupling layer provides direct exchange interaction coupling between said first ferromagnetic layer and said second ferromagnetic layer. 
   
     
     
         41 . The apparatus of  claim 40  wherein said magnetic grains are distributed substantially uniformly within said coupling layer. 
     
     
         42 . The apparatus of  claim 40  wherein said magnetic grains include Co, Fe, or alloys thereof, and wherein further said alloys thereof include Cr, Pt, Ta, B, Mo, Ru, Si, Ge, Nb, or Ni. 
     
     
         43 . The apparatus of  claim 40  wherein said coupling layer has a magnetization greater than 300 emu/cm3. 
     
     
         44 . The apparatus of  claim 40  wherein said coupling layer has a magnetization greater than 500 emu/cm3. 
     
     
         45 . The apparatus of  claim 40  wherein said first ferromagnetic layer and said second ferromagnetic layer are ferromagnetically coupled together. 
     
     
         46 . The apparatus of  claim 40  wherein said first ferromagnetic layer and said second ferromagnetic layer are anti-ferromagnetically coupled together.