Single-pass defect detection for hard-disk drive systems

Abstract

In one embodiment, defects are detected on the face of a hard-disk drive platter. A preamble, a sync mark, user or pseudorandom data, and a data pad are written to every sector on a track of the platter. Inter-sector gaps that separate consecutive sectors are overwritten with a fixed data pattern such that consecutive sectors are in phase lock with one another. After the track has been written, the track is read back and analyzed. Consecutive sectors are analyzed continuously without stopping. The preambles, sync marks, data pads, and overwritten inter-sector gaps are analyzed using suitable flaw-scan techniques. The user or pseudorandom data is analyzed using both data-integrity checks and suitable flaw-scan techniques. This process is repeated for all tracks on the disk, and defect detection is completed when all tracks have been analyzed.