SURFACE DEFECT MEASUREMENTS OF COMPUTER HARD DISKS

THIS PROPOSAL PRESENTS A RESEARCH PLAN FOR THE MEASUREMENT OF SURFACE DEFECTS ON EITHER HARD DISK MEDIA OR HARD DISK SUBSTRATES. THESE DEFECTS CAN EFFECT THE PERFORMANCE OF A COMPUTER DISK AS THE HEAD TRACKS OVER THE SURFACE. THE PROPOSED RESEARCH PROGRAM IS TO MEASURE SURFACE DEFECTS ON COMPUTER HARD DISKS USING NON-CONTACT OPTICAL SCANNING INTERFEROMETRY. THE EFFECTS OF SIGNAL TO NOISE RATIO, SIGNAL BANDWIDTH, LASER SPOT SIZE, AND FOCUSING ERRORS WILL BE STUDIED FOR SEVERAL DISK ROTATION SPEEDS. THE ANTICIPATED RESULT OF THE PHASE I RESEARCH WILL BE THE CHARACTERIZATION OF A COMPUTER HARD DISK SURFACE AROUND ONE CIRCULAR SEGMENT. THE IMPLICATION OF THIS RESEARCH IS THE POTENTIAL FOR A RAPID NON-CONTACTING MEASUREMENT TECHNIQUE OF SURFACE FEATURES OF A FINISHED HARD DISK OR UNCOATED HARDDISK SUBSTRATE. THE POTENTIAL APPLICATION OF THIS RESEARCH IS THE DEVELOPMENT OF NEW MEASUREMENT TECHNIQUES AND TEST EQUIPMENT FOR THE COMPUTER INDUSTRY. THESE NEW MEASUREMENT TECHNIQUES AND TEST EQUIPMENT WILL HAVE THE POTENTIAL TO IMPROVE THE QUALITY OF COMPUTER HARD DISKS.