Impact of Shallow Void Corrosion on HDD Initialization Failures

This paper investigates how corrosion growth that originates from shallow film voids on thin film sputtered magnetic media can impact the final HDD system performance. The impact of shallow void corrosion [1] in HDD system can be both on its behavior during initialization i.e. servo write formatting and initial defect mapping, and on its long term reliability. One of the main concerns for HDD reliability due to media is the occurrence of a condition called metallic smear. Metallic smear is a contamination of the head-pole area that causes an unstable fly height condition. Metallic smear is possibly caused by media corrosion and therefore void corrosion is a logical concern. However, our study shows that shallow void corrosion is not associated with metallic smear risk and does not contribute to HDD initialization failures.