Patent ID: 9312064
Filing Date: 2016-04-12
CPC Classification: G11B,H01F

Claim Text:
1. A method to manufacture a magnetic head, the method comprising: providing a first layered structure including a magnetic layer, a first hard mask layer immediately adjacent and contacting the magnetic layer, a second hard mask layer immediately adjacent and contacting the first hard mask layer; and a first stepping layer immediately adjacent and contacting the second hard mask layer; etching through the first stepping layer to create a sidewall of the first stepping layer; depositing a mask-width definition layer on and adjacent to the sidewall, until a mask-width definition layer thickness is achieved adjacent to the sidewall; removing the mask-width definition layer except on the sidewall; removing the first stepping layer; etching away the second hard mask layer except for a remainder of the second hard mask layer beneath the mask-width definition layer; etching away the first hard mask layer around the remainder of the second hard mask layer to define a remainder of the first hard mask layer beneath the remainder of the of the second hard mask layer, to form a dual layer hard mask comprising the remainder of the second hard mask layer and the remainder of the first hard mask layer; and ion milling the magnetic layer around the dual hard mask.