Isotropic texturing of amorphous carbon substrate by catalytic oxidation

A novel texture process using catalytic oxidation for ultra densified amorphous carbon substrates (UDAC) has been developed. The oxidation temperature is reached by means of either furnace annealing or heat absorption due to a CO₂ laser. Catalytic oxidation resulted in isotropic texturing of the UDAC, devoid of scratches, pits or asperities. Flying height of ≈50 nm was obtained on these isotropically textured disks and the static magnetic properties were not affected. Texture-Induced Modulation Noise determined as a result of isotropic texturing was comparable to that observed on polished UDAC. This was attributed to the absence of scratch marks which cause a broadening in the readback of the write signal, as is the case with mechanically textured disks. Zone texturing was successfully accomplished by changing the laser beam width