Chemical Mechanical Polishing of Computer Hard Disk Substrate in Colloidal SiO_2 Slurry

摘要

With magnetic heads operating closer to the disks, the hard disks are forced to be ultra-smooth. At present, chemical-mechanical polishing (CMP) has become a widely accepted technology for global planarization. Chemical-mechanical polishing of hard disk substrate with nickel-phosphorous plated in colloidal SiO_2 slurry has been studied in the paper. Chapman MP2000~+ surface profiler shows that the average roughness (Ra) and waviness (Wa) of the surface are reduced to 0.55 A and 0.90 A respectively, those are the lowest values reported to date for hard disk polishing. Atom force microscopy (AFM) shows that a very smooth finishing surface has been obtained.