Patent ID: 7631418

Claim:
A process to form an air bearing surface for a planar magnetic write head, comprising: providing a lower magnetic pole, having a first top surface and a second top surface that is parallel to, and lower than, said first top surface, thereby forming a step; forming a cavity that extends downwards from said first top surface and that is filled with a write coil which is covered by a layer of insulation whose top surface is coplanar with said first top surface; coating said layer of insulation and said first and second top surfaces with a layer of photoresist; forming a mold from said layer of photoresist, said mold covering all surfaces except an area that extends from an edge of said cavity to a distance that is sufficient to fully expose said step; through electroplating, depositing a layer of non-magnetic material to a thickness sufficient to cover all of said step; removing said mold and then planarizing until said layer of non-magnetic material has a third top surface that is coplanar with said first top surface; then forming an upper magnetic pole on said first and third top surfaces and on said layer of insulation; and then simultaneously polishing said upper and lower magnetic poles as well as said layer of non-magnetic material until a thickness of said layer of non-magnetic material remains, thereby forming said air bearing surface without stressing either of said magnetic poles.