# US 7,612,963 B2 · Perpendicular magnetic recording head with photoresist dam between write coil and air bearing surface > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,612,963 B2 - Document ID: US7612963B2 - Status: Granted - Kind: B2 - Application number: 11/478,925 - Filed: 2006-06-30 - Published: 2008-01-03 - Granted: 2009-11-03 - Earliest claimed: 2006-06-30 - Assignees: Hitachi Global Storage Technologies Netherlands B.V. - Inventors: Donald G. Allen; Edward Hin Pong Lee; Jennifer Ai-Ming Leung - Web page: https://patentgrep.com/patent/US7612963B2 ## CPC - G11B 5/1278: {specially adapted for magnetisations perpendicular to the surface of the record carrier} - G11B 5/3123: {by using special coil configurations or conductors} - G11B 5/3163: {Fabrication methods or processes specially adapted for a particular head structure, e.g. using base layers for electroplating, using functional layers for masking, using energy or particle beams for shaping the structure or modifying the properties of the basic layers} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A magnetic recording head for use in perpendicular magnetic recording having a design that allows the write coil to be manufactured by a damascene process for increased coil pitch and reduced coil resistance. The magnetic write head includes a photoresist dam structure that allows a hard baked photoresist to be formed that does not extend to the air bearing surface (ABS). Since the photoresist dam prevents the hard baked photoresist from reaching the ABS, the damascene process, in which the hard baked photoresist remains in the finished write head, can be used to produce the write head. The use of such a damascene process advantageously allows the space between the coil turns to be reduced, which maximizes the number of turns that can be used and also maximizes the number width to which the coil turns can be constructed, thereby minimizing the electrical resistance of the write coil. ## Claims ### Claim 1 A magnetic write head for perpendicular magnetic data recording, the write head having an air bearing surface (ABS), the magnetic write head comprising: a magnetic return pole; a magnetic write pole that is magnetically connected with the return pole in a region away from the ABS; a write coil passing between the write pole and the return pole, the write coil being electrically insulated from the write pole and return pole; and a photoresist dam disposed between the write coil and the ABS; wherein the photoresist dam comprises an electrically conductive material and contacts the write coil. ### Claim 2 (depends on 1) A magnetic write head as in claim 1, wherein the photoresist dam and the write coil both comprise copper (Cu) and wherein the photoresist dam contacts the write coil. ### Claim 3 A magnetic write head for perpendicular magnetic data recording, the write head having an air bearing surface (ABS), the magnetic head comprising: a magnetic return pole; a magnetic write pole that is magnetically connected with the return pole in a region away from the ABS; a write coil having a plurality of turns, a portion of which pass between the write pole and the return pole, the write coil being electrically insulated from the write pole and return pole; a coil insulation layer comprising hard baked photoresist disposed between and insulating the turns of the coil from one another; and a photoresist dam disposed between the write coil and the ABS; wherein the photoresist dam and the write coil are constructed of the same electrically conductive material. ### Claim 4 (depends on 3) A magnetic write head as in claim 3 further comprising a fill layer comprising alumina disposed between the photoresist dam and the ABS. ### Claim 5 (depends on 3) A magnetic write head as in claim 3 wherein the photoresist dam contacts the write coil. ### Claim 6 (depends on 3) A magnetic write head as in claim 3 wherein the photoresist dam and the coil both comprise copper (Cu) and wherein the photoresist dam contacts the write coil. ### Claim 7 A magnetic write head for perpendicular magnetic data recording, the write head having an air bearing surface (ABS), the magnetic head comprising: a magnetic return pole; a magnetic write pole that is magnetically connected with the return pole in a region away from the ABS; an electrically conductive write coil having a plurality of turns, a portion of which pass between the write pole and the return pole; a coil insulation layer comprising hard baked photoresist, a portion of which is disposed between the turns of the write coil; and an alumina fill layer disposed between the write coil and the ABS; wherein the write coil has an outermost turn that passes closer to the ABS than the other coil turns, and wherein the outermost coil turn is wider than the other coil turns in a region where the coil turns pass between the return pole and the write pole; and wherein the outermost coil turn, in the region that passes between the return pole and the write pole, comprises a coil turn portion and a photoresist dam portion, both of which are constructed of copper (Cu).