PASS WEAR DURABILITY AND DEFECT BEHAVIOR FOR Co-Cr THIN FILM MEDIA

The influence of media defects on missing signal pulses was studied for a 3.5 inch single sided Co-Cr flexible disk drive. Most of the missing pulses were brought about by relatively large defects, which were induced during the deposition process of the Co-Cr and protective films. Small protuberances of the media due to the substrate film seldom induced the missing pulses. The head run on the top of the surface of the defects in contact. As a result, the defects had a tendency to be worn down and became flat, but the wear rate was extremely slow, different from the case of small protuberances. The wear rate for a defect in a thin film medium depended on, first, the head surface condition, second, the size and shape of the defect. The authors confirmed the possibility of defect burnishing without leading to serious problems.