# US 7,611,911 B2 · Method and system for patterning of magnetic thin films using gaseous transformation to transform a magnetic portion to a non-magnetic portion > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,611,911 B2 - Document ID: US7611911B2 - Status: Granted - Kind: B2 - Application number: 10/680,260 - Filed: 2003-10-08 - Published: 2005-04-14 - Granted: 2009-11-03 - Earliest claimed: 2003-10-08 - Assignees: International Business Machines Corporation - Inventors: David William Abraham; Eugene John O'Sullivan - Web page: https://patentgrep.com/patent/US7611911B2 ## CPC - C23F 4/00: Processes for removing metallic material from surfaces, not provided for in group C23F1/00 or C23F3/00 - B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic - B82Y 25/00: Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance - G11B 5/3909: {Arrangements using a magnetic tunnel junction} - H01F 10/3254: {the spacer being semiconducting or insulating, e.g. for spin tunnel junction [STJ]} - H01F 41/34: in patterns, e.g. by lithography - H10N 50/01: Manufacture or treatment - G11B 5/3116: {Shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect, equalizing, side flux fringing, cross talk reduction between heads or between heads and information tracks (G11B5/3113, G11B5/245 take precedence)} - 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 5/3903: {using magnetic thin film layers or their effects, the films being part of integrated structures} - H01F 41/308: {lift-off processes, e.g. ion milling, for trimming or patterning} - Y10T 428/12542: More than one such component - C23F: NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE (working metal by laser beams B23K26/00; desurfacing by applying flames B23K7/00; working of metal by electro-erosion B23H; producing decorative effects by removing surface material, e.g. by engraving, by etching, B44C1/22; electrolytic etching or polishing C25F); INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25 - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - 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) - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A method (and resulting structure) of patterning a magnetic thin film, includes using a chemical transformation of a portion of the magnetic thin film to transform the portion to be non-magnetic and electrically insulating. ## Claims ### Claim 1 A method of patterning a magnetic thin film, comprising: transforming a portion of the magnetic thin film to be non-magnetic and electrically insulating using a chemical transformation, said chemical transformation comprises using a reactive plasma comprising a combination of a fluorine-based gas and a bromide-containing gas, wherein said reactive plasma includes 5% to 10% bromide, wherein said portion of said magnetic thin film comprises NiFe and said transforming comprises transforming said NiFe to a fluorine-containing film, and wherein said fluorine-containing film is electrically insulating. ### Claim 2 (depends on 1) The method of claim 1, further comprising: providing a mask over said portion of the magnetic thin film to be preserved using photolithography. ### Claim 3 (depends on 1) The method of claim 1, wherein said fluorine-based gas comprises any of NF3, CF4, SF6, and CHF3. ### Claim 4 (depends on 1) The method of claim 1, wherein a pressure used in said transforming is within a range of about 10 mT to about 30 mT. ### Claim 5 (depends on 2) The method of claim 2, wherein said mask comprises a photoresist. ### Claim 6 (depends on 2) The method of claim 2, wherein said mask comprises a hard mask patterned layer comprising one of diamond-like carbon (DLC), TiN, and TaN. ### Claim 7 (depends on 1) The method of claim 1, wherein said using said chemical transformation is performed at room temperature. ### Claim 8 (depends on 1) The method of claim 1, wherein said reactive plasma includes a fluorocarbon. ### Claim 9 (depends on 1) The method of claim 1, wherein said reactive plasma includes sulfur hexafluoride. ### Claim 10 (depends on 1) The method of claim 1, wherein a pressure is selectively employed for said plasma sputtering such that the magnetic thin film material is substantially free of erosion. ### Claim 11 (depends on 2) The method of claim 2, further comprising: forming an insulating layer over the converted portion of said magnetic thin film and said mask; and etching said insulating layer and said mask to planarize an upper level of the mask and the insulating layer. ### Claim 12 (depends on 11) The method of claim 11, further comprising: selectively etching said mask; and forming a conductive material over the insulating layer and an area where the mask was selectively etched. ### Claim 13 (depends on 2) The method of claim 2, wherein said mask comprises an insulating hard mask, said method further comprising: after said converting, selectively etching said insulating hard mask to remove said insulating hard mask. ### Claim 14 (depends on 13) The method of claim 13, further comprising: forming a conductive material over an area where the insulating hard mask was etched. ### Claim 15 (depends on 1) The method of claim 1, wherein said magnetic thin film includes a magnetic tunnel junction (MTJ), and wherein after said converting said portion, edges of the magnetic tunnel junction have no exposure to oxygen. ### Claim 16 (depends on 15) The method of claim 15, wherein an edge smoothness of the MTJ is determined by a line edge roughness of the mask. ### Claim 17 (depends on 1) The method of claim 1, wherein a pressure used in said transforming is substantially 20 mT.