Highly oriented longitudinal magnetic media on direct textured glass substrates

Abstract

Oriented longitudinal magnetic recording media on direct texture glass or glass-ceramic substrates with a film structure of one or more Ni-containing layer, a Cr-containing underlayer, a Co-containing magnetic layer and carbon overcoat exhibits are capable of achieving Mrt OR of >1.5, preferably >1.85. Such highly oriented glass media shows a significant SNR (>2 dB) and parametric improvement over the counterpart isotropic media with the same film structure on non-textured glass or glass-ceramic substrates.

1 - 20 . (canceled)  
     
     
         21 . A method for manufacturing a magnetic recording medium comprising introducing a direct texture glass or glass-ceramic substrate into a sputtering chamber and forming a film structure on the direct texture glass or glass-ceramic substrate without removal of the glass or glass-ceramic substrate from the sputtering chamber.  
     
     
         22 . The method of  claim 21 , wherein the medium is an oriented longitudinal magnetic recording medium having Mrt OR of 1.5 or more.  
     
     
         23 . The method of  claim 21 , wherein the medium has SNR of greater than 2 dB over an isotropic medium with a defined film structure directly on a non-textured glass or glass-ceramic substrate, the defined film structure being identical to the film structure directly on the direct texture glass or glass-ceramic substrate.  
     
     
         24 . The method of  claim 21 , wherein the film structure comprises an oxidized NiP layer.  
     
     
         25 . The method of  claim 24 , wherein the oxidized NiP layer has a texture resulting substantially from a texture of the texture glass or glass-ceramic substrate and the texture of the oxidized NiP is not a mechanical texture.  
     
     
         26 . The method of  claim 24 , wherein the oxidized NiP layer if formed under a partial pressure of oxygen of between about 2 mT to 20 mT in the sputtering chamber.  
     
     
         27 . The method of  claim 24 , wherein the oxidized NiP layer is deposited at about ambient temperature.  
     
     
         28 . The method of  claim 24 , wherein the film structure further comprises a Cr-containing underlayer on the oxidized NiP layer.  
     
     
         29 . The method of  claim 28 , wherein the Cr-containing underlayer is deposited at a temperature of about 120° C. to 250° C.