# US 7,466,522 B2 · Electrical lead structures having crystalline structures that match underlying magnetic hard bias layers for magnetoresistive sensors > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,466,522 B2 - Document ID: US7466522B2 - Status: Granted - Kind: B2 - Application number: 11/363,435 - Filed: 2006-02-27 - Published: 2006-07-06 - Granted: 2008-12-16 - Earliest claimed: 2003-07-30 - Assignees: Hitachi Global Storage Technologies Netherlands B.V. - Inventors: Michael Andrew Parker; Mustafa Michael Pinarbasi - Web page: https://patentgrep.com/patent/US7466522B2 ## CPC - G11B 5/3906: {Details related to the use of magnetic thin film layers or to their effects} - G01R 33/09: Magnetoresistive devices - H10N 50/10: Magnetoresistive devices - 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) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR ## Abstract A magnetic head including an electrical lead layer that is comprised of a material having an ordered-phase crystalline structure. In a preferred embodiment, the ordered-phase crystalline structure of the electrical lead is epitaxially matched to the crystalline structure of the hard bias layer upon which it is formed, and there is no need for a seed layer for the electrical leads. Electrical leads comprised of the materials used in the invention having an ordered-phase crystalline structure, particularly a B2, L10, L11, and L12 structure, will have significantly reduced resistivity over the prior art electrical leads that are typically composed of rhodium or tantalum. As a result, thinner electrical leads can be fabricated which carry the same, or even greater, current than the prior art rhodium or tantalum leads. The preferred leads are comprised of NiAl, FeCo, or CuZn having a B2 crystalline structure, and alternative embodiments are comprised of CuAu, Cu3Au, CuPt, and Cu3Pt. ## Claims ### Claim 1 A magnetic head having a magnetoresistive sensor, comprising: a plurality of sensor layers; a hard bias/lead structure being disposed at side areas of said sensor layers, said hard bias/lead structure including an electrical lead layer having an ordered-phase crystalline structure; and wherein said electrical lead layer is comprised of a material selected from the group consisting of CuZn, FeCo, CuPt and Cu3Pt. ### Claim 2 (depends on 1) A magnetic head as described in claim 1 wherein said hard bias/lead structure includes a hard bias layer having a crystalline structure, and wherein said ordered-phase crystalline structure of said electrical lead layer is epitaxially matched to said crystalline structure of said hard bias layer. ### Claim 3 (depends on 2) A magnetic head as described in claim 2 wherein said lead layer is formed with a B2 structure comprised of an alloy selected from the group consisting of CuZn and FeCo. ### Claim 4 (depends on 3) A magnetic head as described in claim 3 wherein said lead layer is comprised of an alloy of CuZn, wherein the Cu composition ranges from approximately 55 a/o to approximately 50 a/o. ### Claim 5 (depends on 4) A magnetic head as described in claim 4 wherein said Cu composition is approximately 50 a/o. ### Claim 6 (depends on 3) A magnetic head as described in claim 3 wherein said lead layer is comprised of an alloy of FeCo, wherein the Fe composition ranges from approximately 40 a/o to approximately 60 a/o. ### Claim 7 (depends on 6) A magnetic head as described in claim 6 wherein said Fe composition is approximately 50 a/o. ### Claim 8 (depends on 1) A magnetic head as described in claim 1 wherein said hard bias/lead structure includes a hard bias layer that is comprised of a cobalt alloy, and an electrical lead layer that is comprised of an alloy selected from the group consisting of CuZn and FeCo that is deposited directly upon said hard bias layer. ### Claim 9 A hard disk drive including a magnetic head having a magnetoresistive sensor, comprising: a plurality of sensor layers; a hard bias/lead structure being disposed at side areas of said sensor layers, said hard bias/lead structure including a hard bias layer and electrical lead layer having an ordered-phase crystalline structure; and wherein said electrical lead layer is comprised of a material selected from the group consisting of CuZn, FeCo, CuPt and Cu3Pt. ### Claim 10 (depends on 9) A hard disk drive as described in claim 9 wherein said hard bias layer has a crystalline structure, and wherein said ordered-phase crystalline structure of said electrical lead layer is epitaxially matched to said crystalline structure of said hard bias layer. ### Claim 11 (depends on 10) A hard disk drive as described in claim 10 wherein said lead layer is formed with a B2 structure comprised of an alloy selected from the group consisting of CuZn and FeCo. ### Claim 12 (depends on 10) A hard disk drive as described in claim 10 wherein said lead layer is comprised of an alloy of CuZn, wherein the Cu composition ranges from approximately 55 a/o to approximately 50 a/o. ### Claim 13 (depends on 10) A hard disk drive as described in claim 10 wherein said lead layer is comprised of an alloy of FeCo, wherein the Fe composition ranges from approximately 40 a/o to approximately 60 a/o. ### Claim 14 (depends on 9) A hard disk drive as described in claim 9 wherein said hard bias layer is comprised of a cobalt alloy, and said electrical lead layer is comprised of an alloy selected from the group consisting of CuZn and FeCo and is deposited directly upon said hard bias layer.