Patent ID: 8159773

Claim:
A method for forming servo patterns on a magnetic-recording disk, said method comprising: moving a magnetic-recording head in an opposite direction to a pattern development direction, when there is a faulty servo pattern from which data cannot be read by a read element of said magnetic-recording head; positioning a write element of said magnetic recording head on a track where said faulty servo pattern was formed and forming a reserve servo pattern at a different circumferential location from a circumferential location of said faulty servo pattern; moving said magnetic-recording head in said pattern development direction; positioning said read element on said track where said faulty servo pattern was formed and forming a new servo pattern in said pattern development direction by said write element at said circumferential location of said faulty servo pattern on a track disposed between said track where said faulty servo pattern was formed and an outside diameter of said magnetic-recording disk, based on data read from said reserve servo pattern by said read element; moving said magnetic-recording head in said pattern development direction, when said faulty servo pattern exists, and checking in said pattern development direction whether there is another faulty servo pattern on tracks disposed between said track where said faulty servo pattern was formed and an outside diameter of said magnetic-recording disk; and then moving said magnetic-recording head in said opposite direction to said pattern development direction.