# US 7,609,487 B2 · Thin-film PZT micro-actuator integral with suspension of head gimbal assembly, and disk drive unit with the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,609,487 B2 - Document ID: US7609487B2 - Status: Granted - Kind: B2 - Application number: 11/385,704 - Filed: 2006-03-22 - Published: 2007-05-17 - Granted: 2009-10-27 - Earliest claimed: 2005-11-16 - Assignees: SAE Magnetics (H.K.) Ltd. - Inventors: MingGao Yao; LiYan Zhu; Masashi Shiraishi - Web page: https://patentgrep.com/patent/US7609487B2 ## CPC - G11B 5/4826: {Mounting, aligning or attachment of the transducer head relative to the arm assembly, e.g. slider holding members, gimbals, adhesive (G11B5/484 takes precedence; details of head housings or structures G11B5/10, G11B5/127; adjustment relative to the record carrier G11B5/56)} - G11B 5/4853: {Constructional details of the electrical connection between head and arm} - G11B 5/4873: {the arm comprising piezoelectric or other actuators for adjustment of the arm} - G11B 5/5552: {using fine positioning means for track acquisition separate from the coarse (e.g. track changing) positioning means} - 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 micro-actuator for a head gimbal assembly includes a support structure and a PZT element. The support structure includes a bottom support integrated with a suspension flexure of the head gimbal assembly, a top support adapted to support a slider of the head gimbal assembly, and a leading beam that couples the bottom support and the top support. The leading beam includes a weak point that allows the top support to rotate about a rotational axis in use. The PZT element is mounted between the top and bottom supports. The PZT element is excitable to cause selective rotational movement of the top support about the rotational axis in use. ## Claims ### Claim 1 A micro-actuator for a head gimbal assembly, comprising: a support structure including a bottom support integral with a suspension flexure of the head gimbal assembly, a top support adapted to support a slider of the head gimbal assembly, and a leading beam that couples the bottom support and the top support, the leading beam including a weak point that allows the top support to rotate about a rotational axis in use; and a PZT element mounted between the top and bottom supports, the PZT element being excitable to cause selective rotational movement of the top support about the rotational axis in use, wherein the PZT element includes a first PZT portion, a second PZT portion, and a coupling portion that couples the first and second PZT portions. ### Claim 2 (depends on 1) The micro-actuator according to claim 1, wherein the PZT element is a thin-film PZT element, ceramic single crystal, or PMN-PT single crystal. ### Claim 3 (depends on 1) The micro-actuator according to claim 1, wherein the top support and the leading beam define a T-shaped arrangement. ### Claim 4 (depends on 1) The micro-actuator according to claim 1, wherein the first and second PZT portions are mounted to the top support and the coupling portion is mounted to the bottom support. ### Claim 5 (depends on 4) The micro-actuator according to claim 4, wherein the first and second PZT portions are partially mounted to the top support by epoxy dots. ### Claim 6 (depends on 4) The micro-actuator according to claim 4, wherein the coupling portion is partially mounted to the bottom support by anisotropic conductive film (ACF). ### Claim 7 (depends on 6) The micro-actuator according to claim 6, wherein the coupling portion of the PZT element includes multiple bonding pads and the bottom support includes multiple bonding pads communicated with suspension traces of the suspension flexure, the multiple bonding pads of the coupling portion being electrically connected to the multiple bonding pads of the bottom support by the ACF. ### Claim 8 (depends on 4) The micro-actuator according to claim 4, wherein each of the first and second PZT portions include a notch on an inner side thereof. ### Claim 9 (depends on 4) The micro-actuator according to claim 4, wherein each of the first and second PZT portions include a notch on an outer side thereof. ### Claim 10 (depends on 4) The micro-actuator according to claim 4, further comprising a polymer layer provided to the leading beam. ### Claim 11 (depends on 10) The micro-actuator according to claim 10, wherein each of the first and second PZT portions include a notch on an inner side thereof. ### Claim 12 (depends on 10) The micro-actuator according to claim 10, wherein each of the first and second PZT portions include a notch on an outer side thereof. ### Claim 13 (depends on 1) The micro-actuator according to claim 1, wherein the first and second PZT portions have the same polarization direction. ### Claim 14 (depends on 1) The micro-actuator according to claim 1, wherein the first and second PZT portions have opposite polarization directions. ### Claim 15 (depends on 1) The micro-actuator according to claim 1, wherein the PZT element is made of a single-layer PZT material or a multi-layer PZT material. ### Claim 16 (depends on 1) The micro-actuator according to claim 1, wherein the top support includes a step constructed of a polymer laminate to support the slider. ### Claim 17 (depends on 1) The micro-actuator according to claim 1, further comprising a polymer layer provided to the leading beam. ### Claim 18 A head gimbal assembly comprising: a micro-actuator; a slider; and a suspension including a suspension flexure, wherein the micro-actuator includes: a support structure including a bottom support integral with the suspension flexure, a top support that supports the slider, and a leading beam that couples the bottom support and the top support, the leading beam including a weak point that allows the top support to rotate about a rotational axis in use; and a PZT element mounted between the top and bottom supports, the PZT element being excitable to cause selective rotational movement of the top support about the rotational axis in use, wherein the PZT element includes a first PZT portion, a second PZT portion, and a coupling portion that couples the first and second PZT portions. ### Claim 19 (depends on 18) The head gimbal assembly according to claim 18, wherein the PZT element is a thin-film PZT element, ceramic single crystal, or PMN-PT single crystal. ### Claim 20 (depends on 18) The head gimbal assembly according to claim 18, wherein the suspension includes a load beam, the load beam having a dimple that engages the weak point of the leading beam. ### Claim 21 (depends on 20) The head gimbal assembly according to claim 20, wherein a center of the slider, the weak point, and the dimple are aligned along a common axis. ### Claim 22 (depends on 18) The head gimbal assembly according to claim 18, wherein the top support includes a step constructed of a polymer laminate to support the slider. ### Claim 23 (depends on 22) The head gimbal assembly according to claim 22, wherein the slider is partially mounted on the step by epoxy or adhesive. ### Claim 24 (depends on 22) The head gimbal assembly according to claim 22, wherein a parallel gap is provided between the slider and the PZT element. ### Claim 25 (depends on 18) The head gimbal assembly according to claim 18, wherein the top support and the leading beam define a T-shaped arrangement. ### Claim 26 (depends on 18) The head gimbal assembly according to claim 18, wherein the first and second PZT portions are mounted to the top support and the coupling portion is mounted to the bottom support. ### Claim 27 (depends on 26) The head gimbal assembly according to claim 26, wherein the first and second PZT portions are partially mounted to the top support by epoxy dots. ### Claim 28 (depends on 26) The head gimbal assembly according to claim 26, wherein the coupling portion is partially mounted to the bottom support by anisotropic conductive film (ACF). ### Claim 29 (depends on 28) The head gimbal assembly according to claim 28, wherein the coupling portion of the PZT element includes multiple bonding pads and the bottom support includes multiple bonding pads communicated with suspension traces of the suspension flexure, the multiple bonding pads of the coupling portion being electrically connected to the multiple bonding pads of the bottom support by the ACF. ### Claim 30 (depends on 26) The head gimbal assembly according to claim 26, wherein each of the first and second PZT portions include a notch on an inner side thereof. ### Claim 31 (depends on 26) The head gimbal assembly according to claim 26, wherein each of the first and second PZT portions include a notch on an outer side thereof. ### Claim 32 (depends on 26) The head gimbal assembly according to claim 26, further comprising a polymer layer provided to the leading beam. ### Claim 33 (depends on 32) The head gimbal assembly according to claim 32, wherein each of the first and second PZT portions include a notch on an inner side thereof. ### Claim 34 (depends on 32) The head gimbal assembly according to claim 32, wherein each of the first and second PZT portions include a notch on an outer side thereof. ### Claim 35 (depends on 18) The head gimbal assembly according to claim 18, wherein the first and second PZT portions have the same polarization direction. ### Claim 36 (depends on 18) The head gimbal assembly according to claim 18, wherein the first and second PZT portions have opposite polarization directions. ### Claim 37 (depends on 18) The head gimbal assembly according to claim 18, wherein the PZT element is made of a single-layer PZT material or a multi-layer PZT material. ### Claim 38 (depends on 18) The head gimbal assembly according to claim 18, further comprising a polymer layer provided to the leading beam. ### Claim 39 A disk drive device comprising: a head gimbal assembly including a micro-actuator, a slider, and a suspension including a suspension flexure; a drive arm connected to the head gimbal assembly; a disk; and a spindle motor operable to spin the disk, wherein the micro-actuator includes: a support structure including a bottom support integral with the suspension flexure, a top support that supports the slider, and a leading beam that couples the bottom support and the top support, the leading beam including a weak point that allows the top support to rotate about a rotational axis in use; and a PZT element mounted between the top and bottom supports, the PZT element being excitable to cause selective rotational movement of the top support about the rotational axis in use, wherein the PZT element includes a first PZT portion, a second PZT portion, and a coupling portion that couples the first and second PZT portions. ### Claim 40 A head gimbal assembly comprising: a micro-actuator; a slider; and a suspension including a suspension flexure, the micro-actuator includes: a support structure including a bottom support integral with the suspension flexure, a top support that supports the slider, and a leading beam that couples the bottom support and the top support, the leading beam including a weak point that allows the top support to rotate about a rotational axis in use; and a PZT element mounted between the top and bottom supports, the PZT element being excitable to cause selective rotational movement of the top support about the rotational axis in use, wherein the suspension includes a load beam having a dimple that engages the weak point of the leading beam, and wherein a center of the slider, the weak point, and the dimple are aligned along a common axis. ### Claim 41 (depends on 40) The head gimbal assembly according to claim 40, wherein the top support includes a step constructed of a polymer laminate to support the slider. ### Claim 42 (depends on 41) The head gimbal assembly according to claim 41, wherein the slider is partially mounted on the step by epoxy or adhesive. ### Claim 43 (depends on 41) The head gimbal assembly according to claim 41, wherein a parallel gap is provided between the slider and the PZT element. ### Claim 44 A method for manufacturing a head gimbal assembly, comprising: forming a micro-actuator support structure integral with a suspension flexure; applying a bonding material to the micro-actuator support structure; aligning a PZT element with the micro-actuator support structure, the PZT element including a first PZT portion, a second PZT portion, and a coupling portion that couples the first and second PZT portions; bonding the PZT element to the micro-actuator support structure by the bonding material to physically and electrically connect the PZT element to suspension traces provided on the micro-actuator support structure; mounting a slider to the micro-actuator support structure; electrically connecting the slider to suspension traces provided on the micro-actuator support structure; and performing a resistance check and a visual check. ### Claim 45 (depends on 44) The method according to claim 44, wherein applying a bonding material includes applying ACF and epoxy to the micro-actuator support structure.