JP2009054230A - Magnetic recording apparatus and suspension - Google Patents

Abstract

A magnetic recording apparatus and a suspension for a magnetic recording apparatus capable of detecting suspension distortion with higher sensitivity and detecting the flying height of a magnetic head element with high accuracy.
A leaf spring-like suspension is provided at the tip of an arm to urge a magnetic head element toward a magnetic disk. The suspension 25 is provided with an opening 25a, and a piezoelectric sensor 27 is attached so as to cut the opening 25a vertically. Since the rigidity around the opening 25 is low, when the magnetic head element 23 floats as the magnetic disk 22 rotates, the distortion generated in the suspension 25 concentrates around the opening 25 and is caused by the piezoelectric sensor 27. It is detected efficiently.
[Selection] Figure 2

Description

  The present invention relates to a magnetic recording apparatus for writing data to or reading data from a magnetic recording medium and a suspension used in the magnetic recording apparatus, and more particularly to a magnetic recording provided with a sensor for detecting the flying height of a magnetic head element. The present invention relates to a device and a suspension.

  FIG. 1 is a plan view showing a general structure of a magnetic recording device (hard disk device).

  The magnetic recording apparatus 10 includes a housing 11, a disk-shaped magnetic disk (magnetic recording medium) 12 disposed in the housing 11, a spindle motor (not shown) that rotates the magnetic disk 12, and a magnetic head An arm 14 that supports the element 13, a voice coil motor (not shown) that drives the arm 14, a spindle motor and a voice coil motor are controlled, and data is written to the magnetic disk 12 via the magnetic head element 13 A control circuit unit (electronic circuit) 16 that performs reading is configured.

  The central portion of the magnetic disk 12 is connected to the rotation shaft 12a of the spindle motor, and rotates at a high speed around the rotation shaft 12a. The arm 14 is connected to the drive shaft 14a of the voice coil motor, and rotates around a certain angle range around the drive shaft 14a. A leaf spring suspension 15 is provided at the tip of the arm 14, and a magnetic head element 13 is disposed on the surface of the tip of the suspension 15 on the magnetic disk 12 side. The magnetic head element 13 is composed of a substantially rectangular parallelepiped member called a slider, and a read element (such as a magnetoresistive element) and a write element (inductive head element) disposed on the end face of the slider.

  In the magnetic recording apparatus 10 configured as shown in FIG. 1, when the magnetic disk 12 is rotated at a high speed by the spindle motor, the magnetic head element 13 slightly floats from the magnetic disk 12 due to the air flow generated by the rotation of the magnetic disk 12. . The flying height of the magnetic head element 13 at this time is determined by the wind pressure accompanying the rotation of the magnetic disk 12 and the urging force of the suspension 15 against the magnetic head element 13. The control circuit unit 16 controls the voice coil motor to drive the arm 14 and moves the magnetic head element 13 to a predetermined position in the radial direction of the magnetic disk 12 to write or read data.

  Conventionally, as described above, the distance between the magnetic head element 13 and the magnetic disk 12 (the flying height of the magnetic head element 13) is the wind pressure accompanying the rotation of the magnetic disk 12 and the urging force of the suspension 15 against the magnetic head element 13. It was decided by. However, in recent years, as the storage capacity of the magnetic recording apparatus has increased, it has been required to control the distance between the magnetic head element 13 and the magnetic disk 12 with higher accuracy. For this purpose, a sensor for detecting the flying height of the magnetic head element 13 is required.

Patent Document 1 describes that a voltage is applied between a magnetic head element (slider) and a magnetic disk to generate an attractive force to control the distance between the magnetic head element and the magnetic disk. In Patent Document 2, longitudinal and lateral displacements of a magnetic head element are detected by a piezoelectric sensor attached to a suspension, and the flying height of the magnetic head element is controlled by driving the piezoelectric element according to the detection result. It is described to do.
JP-A-9-82014 Japanese Patent Laid-Open No. 11-53856

  In order to detect the flying height of the magnetic head element, for example, as described in Patent Document 2, a piezoelectric sensor (strain sensor) is attached to the surface of the suspension, and the strain amount of the suspension is detected by this piezoelectric sensor. Conceivable. However, it is difficult to obtain sufficient sensitivity for detecting strain by simply attaching a piezoelectric sensor to the surface of the suspension.

  In view of the above, an object of the present invention is to provide a magnetic recording apparatus and a suspension for a magnetic recording apparatus that can detect the strain of the suspension with higher sensitivity and can detect the flying height of the magnetic head element with high accuracy. is there.

  According to one aspect of the present invention, a magnetic recording medium, a magnetic head element that writes or reads data to or from the magnetic recording medium, a suspension that biases the magnetic head element toward the magnetic recording medium, A piezoelectric sensor that is attached to the suspension and detects strain generated in the suspension, and the suspension is provided with an opening, and the piezoelectric sensor is attached to the suspension so as to cut through the opening. A magnetic recording device is provided.

  According to another aspect of the present invention, in a suspension that is used in a magnetic recording apparatus and biases a magnetic head element toward a magnetic recording medium, a suspension body, an opening provided in the suspension body, There is provided a suspension for a magnetic recording apparatus, comprising: a piezoelectric sensor attached to the suspension body so as to cut through the opening.

  In the present invention, the suspension (suspension body) is provided with an opening, so that the rigidity around the opening is lower than that of the other parts, and the magnetic head element floats around the opening when it floats. Distortion is concentrated. Moreover, in this invention, the piezoelectric sensor is attached so that an opening part may be longitudinally cut. Therefore, the strain generated in the suspension when the magnetic head element floats is efficiently transmitted to the piezoelectric sensor, and a signal corresponding to the flying height of the magnetic head element is output from the piezoelectric sensor. Thereby, the flying height of the magnetic head element can be detected with high accuracy.

  As the piezoelectric sensor, for example, a sensor having a structure in which a thin film sensor having a structure in which a piezoelectric film is sandwiched between first and second electrodes is disposed on a substrate such as stainless steel can be used. In this case, by providing the opening in the substrate portion corresponding to the piezoelectric film, the piezoelectric film is not restrained by the substrate, and the sensitivity is increased. Moreover, it is good also as a structure which divided | segmented the board | substrate into two so that a piezoelectric material film may not be restrained with a board | substrate. Furthermore, the sensitivity of the piezoelectric sensor can be further improved by using a crystallized ferroelectric film as the piezoelectric film.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(First embodiment)
FIG. 2 is a plan view showing the structure of the magnetic recording apparatus according to the first embodiment of the present invention.

  The magnetic recording apparatus 20 includes a casing 21, a disk-shaped magnetic disk (magnetic recording medium) 22 disposed in the casing 21, a spindle motor (not shown) that rotates the magnetic disk 22, and a magnetic head. An arm 24 for supporting the element 23, a voice coil motor (not shown) for driving the arm 24, a spindle motor and a voice coil motor are controlled, and data is written to the magnetic disk 22 via the magnetic head element 23. A control circuit unit (electronic circuit) 26 that performs reading is configured.

  The central portion of the magnetic disk 22 is connected to the rotation shaft 22a of the spindle motor, and rotates at a high speed around the rotation shaft 22a. The arm 24 is connected to a drive shaft 24a of the voice coil motor, and rotates around a certain angle range around the drive shaft 24a.

  A leaf spring suspension 25 is provided at the tip of the arm 24, and a magnetic head element 23 is disposed on the surface of the tip of the suspension 25 on the magnetic disk 22 side. The magnetic head element 23 includes a slider having a substantially rectangular parallelepiped shape, and a reading element (such as a magnetoresistive element) and a writing element (inductive head element) disposed on the end face of the slider.

  FIG. 3 is a perspective view showing a state when the suspension 25 of the magnetic recording apparatus 20 of the present embodiment is viewed from the magnetic disk 22 side.

  As shown in FIG. 3, the suspension (suspension body) 25 of the magnetic recording apparatus 20 of this embodiment is formed by processing a thin metal plate such as stainless steel into a predetermined shape, and has a magnetic head element 23 at the tip. It is designed to be attached. The suspension 25 is provided with a relatively large opening (hole) 25a having a substantially triangular shape. The opening 25a has a lower peripheral rigidity than the other portions, and strain concentrates around the opening 25a when the magnetic head element 23 floats. In the present embodiment, the piezoelectric sensor 27 is arranged so as to cut the opening 25 a longitudinally along the longitudinal direction of the suspension 25. Thereby, when the magnetic head element 23 floats, the strain generated in the suspension 25 is efficiently transmitted to the piezoelectric sensor 27, and a signal corresponding to the flying height of the magnetic head element 23 is output from the piezoelectric sensor 27.

  Although not shown in FIG. 3, a plurality of wiring patterns are provided on the surface of the suspension 25 via insulating films, and magnetic head elements (writing elements and reading elements) are provided via these wiring patterns. 23 and the control circuit unit 26 and between the piezoelectric sensor 27 and the control circuit unit 26 are electrically connected. The piezoelectric sensor 27 may be disposed on the surface of the suspension 25 on the magnetic disk 22 side, or may be disposed on the surface opposite to the magnetic disk 22.

  Further, in the present embodiment, the case where the opening 25a is provided in the central portion in the width direction of the suspension 25 is described. However, a notch is provided on one or both sides of the suspension as the opening. You may arrange | position a piezoelectric sensor so that a notch may be longitudinally cut.

  In the magnetic recording apparatus 20 according to the present embodiment configured as shown in FIG. 2, when the magnetic disk 22 is rotated at a high speed by the spindle motor, the magnetic head element 23 is moved by the air flow generated by the rotation of the magnetic disk 22. From the surface. The flying height of the magnetic head element 23 at this time is determined by the wind pressure accompanying the rotation of the magnetic disk 22 and the urging force of the suspension 25 against the magnetic head element 23. The control circuit unit 26 controls the voice coil to move the magnetic head element 23 in the radial direction of the magnetic disk 22 and writes or reads data to or from the magnetic disk 22.

  When the magnetic head element 23 floats from the surface of the magnetic disk 22, a distortion corresponding to the flying height of the magnetic head element 23 is generated in the suspension 25. The piezoelectric sensor 27 detects distortion generated in the suspension 25 and outputs a signal corresponding to the detection result to the control circuit unit 26. The control circuit unit 26 detects the flying height of the magnetic head element 23 based on the signal output from the piezoelectric sensor 27 and controls the flying height of the magnetic head element 23 as necessary. As a method for controlling the flying height of the magnetic head element 23, for example, a method using an electrical attractive force as described in Patent Document 1 or a method using a piezoelectric element as described in Patent Document 2 and so on.

  In the present embodiment, as described above, the suspension 25 is provided with the relatively large opening 25a. Therefore, when stress is applied to the suspension 25, strain concentrates around the opening 25a. In this embodiment, since the piezoelectric sensor 27 is disposed so as to cut through the opening 25a, strain generated in the suspension 25 is efficiently transmitted to the piezoelectric sensor 27. Thereby, the piezoelectric sensor 27 can detect a minute strain generated in the suspension 25, and as a result, the flying height of the magnetic head element 23 can be detected with good accuracy.

4A is a perspective view showing the piezoelectric sensor 27, and FIG. 4B is a cross-sectional view of the piezoelectric sensor 27 taken along the line AA in FIG. 4A. As shown in FIGS. 4A and 4B, the piezoelectric sensor 27 is formed on a substrate 30 made of stainless steel. Lead zirconate titanate (Pb (Zr, Ti) O ₃ : PZT ”), barium titanate (BaTiO ₃ : commonly called“ BTO ”), or lead lanthanum zirconate titanate ((Pb, La) (Zr, Ti) O ₃ : usually called“ PLZT ”. ) Or the like is sandwiched between a lower electrode 32 and an upper electrode 34 made of a metal such as platinum (Pt) or iridium (Ir). The material of the piezoelectric film 33 is not limited to the ferroelectric material described above, but is preferably formed of a ferroelectric material because of its large piezoelectric constant.

  An insulating layer 31 is provided between the lower electrode 32 and the substrate 30 so that the lower electrode 32 and the substrate 30 are electrically separated. The substrate 30 and the insulating layer 31 are provided with a rectangular opening through which the lower electrode 32 is exposed. The piezoelectric sensor 27 is composed of a thin film sensor section constituted by a piezoelectric film 33, a lower electrode 32 and an upper electrode 34 sandwiched between the piezoelectric film 33, and a frame-like substrate 30 that supports the thin film sensor section. It is a kind of diaphragm.

  A wiring 35 a is bonded (bonded) to the lower electrode 32, and a wiring 35 b is electrically connected to the upper electrode 34. The wiring 35a is connected to a wiring pattern provided on the lower side of the suspension 25, and is connected to the control circuit unit 26 through this wiring pattern. Similarly, the wiring 35b is connected to a wiring pattern provided on the upper side of the suspension 25, and is connected to the control circuit unit 26 through this wiring pattern.

  In such a piezoelectric sensor 27, when pressure (strain) is applied to the piezoelectric film 33, charges corresponding to the pressure are generated in the piezoelectric film 33. By detecting this charge with a charge amplifier, the magnitude of the pressure generated in the piezoelectric film 33 can be known. In the piezoelectric sensor 27 of the present embodiment, an opening is provided in the substrate 30 as shown in FIG. 4B, and deformation of the piezoelectric film 33 is not constrained by the substrate 30 or the suspension 25, so that good sensitivity is obtained. can get.

  5 and 6 are cross-sectional views showing the method of manufacturing the piezoelectric sensor 27 in the order of steps.

  First, as shown in FIG. 5A, a substrate 30 made of a metal thin film such as stainless steel is prepared. Then, a silica layer or an alumina layer is formed on the substrate 30 as the insulating layer 31 to a thickness of, for example, 200 nm by, for example, sputtering. Thereafter, the lower electrode 32 made of a metal such as platinum or iridium is formed to a thickness of 200 nm on the insulating layer 31 by, for example, sputtering or vacuum deposition. The lower electrode 32 may be formed of a conductive nitride film such as TiN or a conductive oxide such as ITO (Indium-Tin Oxide) instead of platinum or iridium.

  Next, as shown in FIG. 5B, a piezoelectric film (electrostrictive film) 33 is formed on the lower electrode 32. In the present embodiment, a PZT film is formed to a thickness of 2 μm as the piezoelectric film 33. The PZT film can be formed using a low-temperature film formation process such as a hydrothermal synthesis method or an aerosol deposition method.

  Next, as shown in FIG. 5C, an upper electrode 34 made of a metal such as platinum or iridium is formed on the piezoelectric film 33 to a thickness of 200 nm, for example. Similarly to the lower electrode 32, the upper electrode 34 may be formed of a conductive nitride film such as TiN or a conductive oxide such as ITO.

  The upper electrode 34 is preferably formed slightly smaller than the piezoelectric film 33 as shown in FIG. For example, a mask made of a thin metal plate (metal through mask) provided with an opening slightly smaller than the piezoelectric film 33 is disposed on the piezoelectric film 33, and then a conductor such as platinum or iridium is sputtered. The upper electrode 34 slightly smaller than the piezoelectric film 33 can be formed. In addition, after a photoresist film is formed on the piezoelectric film 33 in advance, exposure and development are performed to form a resist opening slightly smaller than the piezoelectric film 33, and then a conductor such as platinum or iridium is formed. The upper electrode 34 slightly smaller than the piezoelectric film 33 can be formed by a method (lift-off method) of removing the photoresist film together with the conductor film thereon after sputtering. If the upper electrode 34 is formed by such a method, a short circuit between the upper electrode 34 and the lower electrode 32 can be reliably prevented.

  Next, as shown in FIG. 5D, a photoresist is applied to the lower surface side of the stainless plate 30 to form a photoresist film 36, which is exposed and developed to be slightly smaller than the lower electrode 32, and A rectangular opening 36a through which the substrate 30 is exposed is formed.

  Next, as shown in FIG. 6A, using the photoresist film 36 as a mask, the substrate (stainless steel plate) 30 is wet-etched using an etchant such as hydrofluoric acid. Further, as shown in FIG. 6B, the insulating layer 31 is etched with a hydrofluoric acid aqueous solution or an ammonia aqueous solution to expose the lower electrode 32. Thereafter, as shown in FIG. 6C, the photoresist film 36 is dissolved and removed using a remover (stripping solution).

  After the piezoelectric sensor 27 thus manufactured is joined to the suspension 25 by a method such as spot welding, the upper electrode 34, the lower electrode 32, and the suspension 25 are attached to the suspension 25 using a wire bonding apparatus as shown in FIG. The wiring patterns provided are electrically connected by wirings 35a and 35b. In this way, the suspension 25 including the piezoelectric sensor 27 is completed.

(Second Embodiment)
FIG. 7A is a perspective view showing a piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the second embodiment of the present invention, and FIG. 7B is cut along the line BB in FIG. It is sectional drawing when doing. The magnetic recording device of this embodiment is different from the magnetic recording device of the first embodiment in that the structure of the piezoelectric sensor attached to the suspension is different, and the other configurations are basically the same as those of the first embodiment. Therefore, the description of the overlapping part is omitted here. This embodiment will also be described with reference to FIGS.

  In the piezoelectric sensor 27 according to the first embodiment (see FIG. 4), the substrate 30 has a portion that communicates from one end to the other end in the longitudinal direction, and therefore, distortion generated in the suspension 25 is generated. It can be considered that the substantial sensitivity of the piezoelectric sensor 27 is lowered by being relaxed by the substrate 30. On the other hand, in the piezoelectric sensor 40 used in the present embodiment, the substrate 30 is divided into two as shown in FIGS.

  That is, in the piezoelectric sensor 40 of the present embodiment, as shown in FIG. 7A, since the substrate 30 only reaches the edge of the lower electrode 32, distortion generated in the suspension 25 is relieved by the substrate 30. Without being transmitted to the piezoelectric film 33. Thereby, the piezoelectric sensor 40 of this embodiment has the effect that the sensitivity with respect to distortion improves compared with the piezoelectric sensor 27 of 1st Embodiment.

  The piezoelectric sensor 40 of this embodiment can be manufactured through the same process as the piezoelectric sensor 27 of the first embodiment.

(Third embodiment)
FIG. 8A is a perspective view showing a piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the third embodiment of the present invention, and FIG. 8B is cut along the line CC in FIG. 8A. It is sectional drawing when doing. The magnetic recording device of this embodiment is different from the magnetic recording device of the first embodiment in that the structure of the piezoelectric sensor attached to the suspension is different, and other configurations are basically the same as those of the first embodiment. Therefore, the description of the overlapping parts is omitted here. This embodiment will be described with reference to FIGS.

  The piezoelectric sensor 60 of the present embodiment is formed on a substrate 50 made of stainless steel, and a piezoelectric film 53 made of a crystal-oriented ferroelectric material is applied to a lower electrode 52 made of a conductor such as platinum or gold (Au). And the upper electrode 54. An insulating layer 51 is provided between the lower electrode 52 and the substrate 50 so that the lower electrode 52 and the substrate 50 are electrically separated. The substrate 50 and the insulating layer 51 are provided with a rectangular opening through which the lower electrode 52 is exposed.

  On the piezoelectric film 53, a rod-shaped member 56 made of Si is provided along two opposing sides of the piezoelectric film 53 (sides parallel to the longitudinal direction of the substrate 50). The upper electrode 54 is formed on the piezoelectric film 53 between these rod-shaped members 56.

  The lower electrode 52 is electrically connected to a wiring pattern provided on one surface side of the suspension 25 via a wiring (bonding wire) 55a, and the upper electrode 54 is connected to the other side of the suspension 25 via a wiring (bonding wire) 55b. It is electrically connected to a wiring pattern provided on the surface side of the.

  Also in the piezoelectric sensor 60 shown in FIGS. 8A and 8B, distortion generated in the suspension 25 as the magnetic head element 23 floats is detected efficiently, and the distortion is applied to the control circuit unit 26 (see FIG. 2). A signal corresponding to the size of is output.

  9-12 is sectional drawing which shows the manufacturing method of the above-mentioned piezoelectric sensor 60. As shown in FIG. 9 shows a manufacturing method of the first member 60a constituting the piezoelectric sensor 60, FIG. 10 shows a manufacturing method of the second member 60b constituting the piezoelectric sensor 60, and FIGS. The steps up to combining the member 60a and the second member 60b into the piezoelectric sensor 60 are shown.

  First, with reference to FIGS. 9A to 9C, a method for manufacturing the first member 60a will be described. As shown in FIG. 9A, a substrate 50 made of a stainless steel thin plate is prepared. Then, as shown in FIG. 9B, a silica layer or an alumina layer is formed on the substrate 50 as the insulating layer 51 to a thickness of 200 nm, for example. Thereafter, as shown in FIG. 9C, a first conductor film 52a to be the lower electrode 52 is formed on the insulating layer 51 to a thickness of 100 nm using, for example, platinum or iridium. In this way, the first member 60a is completed.

Next, with reference to FIGS. 10A to 10E, a method for manufacturing the second member 60b will be described. First, as shown in FIG. 10A, a substrate 71 is prepared. In this embodiment, a single crystal substrate of silicon (Si), magnesia (MgO), or sapphire (Al ₂ O ₃ ) is used as the substrate 71 in order to crystallize the piezoelectric film 53. In the case of a silicon substrate, a crystal orientation buffer layer such as yttrium-stabilized zirconia (YSZ) is preferably formed thereon. Here, a silicon substrate is used as the substrate 71.

  Next, a piezoelectric film 53 having a thickness of 2 μm, for example, is formed on the substrate 71. As a method for forming the PZT film, there are a sputtering method, a sol-gel method, a MOCVD (Metal Organic Chemical Vapor Deposition) method, a PLD (Pulsed Laser Deposition) method, and the like. When the PZT film is epitaxially grown on the above-described single crystal substrate, the crystal plane orientation of the PZT film is the same as the cut surface of the single crystal substrate, for example, (001) (111) or (110). It is necessary to select the polarization axis according to the composition or type of the material. In this embodiment, as an example, a PZT (Zr / Ti = 52/48) film is formed as the piezoelectric film 53, and the crystal plane orientation is (001). Thus, by using the ferroelectric film crystal-oriented as the piezoelectric film 53, the polarization direction can be made uniform, and the performance of the piezoelectric sensor is further improved.

  Next, a second conductor film 52b to be the lower electrode 52 is formed on the piezoelectric film 53 to a thickness of 100 nm using, for example, platinum or gold.

  Next, as shown in FIG. 10B, a photoresist film 74 is formed under the substrate 71 and over the second conductive film 52b. Then, exposure and development are performed to form an opening 74 a in the photoresist film 74 below the substrate 71.

  Next, as shown in FIG. 10C, using the photoresist film 74 as a mask, the substrate 71 is wet etched using, for example, an alkaline aqueous solution containing KOH to expose the piezoelectric film 53. The substrate 71 may be etched by dry etching using a halogen-based gas or a fluorine-based gas. A portion of the substrate 71 remaining after the etching becomes a rod-shaped member 56 shown in FIG.

  Next, as shown in FIG. 10D, the upper surface of the piezoelectric film 53 is formed through the opening 74a of the photoresist film 74 on the lower side of the substrate 71 by sputtering or the like (the lower side in FIG. 10D). A film made of a conductor such as platinum or gold is formed to a thickness of, for example, 200 nm to form the upper electrode 54. Next, as shown in FIG. 10E, the photoresist film 74 is removed. In this way, the second member 60b is completed.

  Hereinafter, with reference to FIG. 11 and FIG. 12, a process until the piezoelectric member 60 is obtained by combining the first member 60a and the second member 60b will be described.

  After the first member 60a and the second member 60b are formed in the above-described process, as shown in FIG. 11A, the second member 60b is disposed on the first member 60a and the lower electrode 52b is disposed on the first member 60a. The lower electrode 52a and the lower electrode 52b are joined with the formed surface facing down. As a method for bonding the lower electrode 52a and the lower electrode 52b, there are a room temperature bonding method, an ultrasonic metal bonding method, a diffusion bonding method, and the like. By this joining, the lower electrode 52a and the lower electrode 52b are integrated to form the lower electrode 52.

  Note that room temperature bonding is also called surface activation bonding, and is a method in which the bonds of the surface atoms are directly bonded by removing the surface layer that hinders bonding. In the ultrasonic metal bonding, the members to be bonded are superposed to give pressure and strong ultrasonic vibration, and the solid phase bonding is performed by rubbing the interface between the members. Diffusion bonding is a method in which two members are heated while applying pressure to cause mutual diffusion of atoms to bond the members together.

  Next, as shown in FIG. 11B, a photoresist film 76 is formed on the lower side and the upper side of the substrate 50. Then, exposure and development processes are performed to form an opening 76 a in which the substrate 50 is exposed in the photoresist film 76 on the lower side of the substrate 50.

  Next, as shown in FIG. 11C, the substrate 50 is etched using the photoresist film 76 as a mask to form a rectangular opening through which the lower electrode 52 is exposed. Thereafter, as shown in FIG. 12A, the photoresist film 76 is removed.

  After the piezoelectric sensor 60 thus manufactured is connected to the suspension 25 by a method such as spot welding, the upper electrode 54, the lower electrode 52, and the suspension 25 are attached to the suspension 25 using a wire bonding apparatus as shown in FIG. The wiring pattern provided is electrically connected by wirings 56a and 56b. In this way, a suspension including the piezoelectric sensor 60 is completed.

  The rod-shaped member 56 may be completely removed from the piezoelectric film 52. In this case, the external appearance of the piezoelectric sensor is as shown in FIGS.

(Fourth embodiment)
FIG. 13A is a perspective view showing a piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the fourth embodiment of the present invention, and FIG. 13B is cut along the line DD in FIG. 13A. It is sectional drawing when doing. This embodiment is different from the third embodiment in that the substrate 50 is divided into two parts, and other configurations are the same as those of the third embodiment. ), The same components as those shown in FIGS.

  In the piezoelectric sensor 60 of the third embodiment (see FIGS. 8A and 8B), the substrate 50 has a portion that communicates from one end to the other end in the longitudinal direction. On the other hand, in the piezoelectric sensor 80 used in the present embodiment, the substrate 50 is divided into two as shown in FIGS.

  That is, in the piezoelectric sensor 80 of the present embodiment, the substrate 50 is only up to the edge of the lower electrode 52, so that the strain generated in the suspension is transmitted to the piezoelectric film 53 without being relaxed by the substrate 50. Thereby, the piezoelectric sensor 80 has the effect that the sensitivity with respect to distortion improves compared with the piezoelectric sensor 60 of 3rd Embodiment.

(Other embodiments)
14A and 14B are perspective views showing other examples of the piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the embodiment of the present invention.

  In the above-described third embodiment (see FIGS. 8A and 8B), the rod-shaped member 56 is formed along the longitudinal edge of the stainless steel substrate 50. FIG. In the illustrated piezoelectric sensor 81, a rod-shaped member 86 made of Si extends in a direction orthogonal to the longitudinal direction of the substrate 50. In the piezoelectric sensor 82 shown in FIG. 14B, a rod-shaped member 86 is formed extending in a direction orthogonal to the longitudinal direction of the stainless steel substrate 50, and the stainless steel substrate 50 is divided into two. In these piezoelectric sensors 81 and 82, similarly to the piezoelectric sensor of the third embodiment, the strain generated in the suspension due to the floating of the magnetic head element can be detected with high sensitivity.

  Hereinafter, various aspects of the present invention will be collectively described as supplementary notes.

(Appendix 1) Magnetic recording medium;
A magnetic head element for writing or reading data on the magnetic recording medium;
A suspension for urging the magnetic head element toward the magnetic recording medium;
A piezoelectric sensor that is attached to the suspension and detects strain generated in the suspension;
An opening is provided in the suspension, and the piezoelectric sensor is attached to the suspension so as to cut through the opening.

(Appendix 2) The piezoelectric sensor is
A substrate,
A first electrode formed on the substrate via an insulating film;
A piezoelectric film formed on the first electrode;
2. The magnetic recording apparatus according to appendix 1, wherein the magnetic recording apparatus includes a second electrode formed on the piezoelectric film.

  (Supplementary note 3) The magnetic recording apparatus according to supplementary note 2, wherein an opening is provided in a portion of the piezoelectric sensor substrate corresponding to the first electrode.

  (Supplementary note 4) The magnetic recording apparatus according to supplementary note 2, wherein the substrate of the piezoelectric sensor is constituted by two members divided in a longitudinal direction of the suspension.

  (Supplementary note 5) The magnetic recording apparatus according to supplementary note 2, wherein the piezoelectric film of the piezoelectric sensor has a crystal orientation.

  (Supplementary Note 6) The first electrode of the piezoelectric sensor is electrically connected to a wiring pattern disposed on the first surface side of the suspension, and the second electrode of the piezoelectric sensor is the second electrode of the suspension. The magnetic recording apparatus according to appendix 2, wherein the magnetic recording apparatus is electrically connected to a wiring pattern arranged on the surface side.

(Supplementary note 7) In a suspension that is used in a magnetic recording apparatus and biases a magnetic head element toward a magnetic recording medium,
The suspension body,
An opening provided in the suspension body;
A suspension for a magnetic recording apparatus, comprising: a piezoelectric sensor attached to the suspension body so as to cut the opening vertically.

(Appendix 8) The piezoelectric sensor is
A substrate,
A first electrode formed on the substrate via an insulating film;
A piezoelectric film formed on the first electrode;
The suspension for a magnetic recording apparatus according to appendix 7, wherein the suspension is configured by a second electrode formed on the piezoelectric film.

  (Supplementary note 9) The suspension for a magnetic recording device according to supplementary note 8, wherein the substrate of the piezoelectric sensor is provided with an opening in a portion corresponding to the first electrode.

  (Supplementary note 10) The suspension for a magnetic recording device according to supplementary note 8, wherein the substrate of the piezoelectric sensor is constituted by two members divided in the longitudinal direction of the suspension.

  (Supplementary note 11) The suspension for a magnetic recording device according to supplementary note 8, wherein the piezoelectric film of the piezoelectric sensor has a crystal orientation.

FIG. 1 is a plan view showing a general structure of a magnetic recording apparatus. FIG. 2 is a plan view showing the structure of the magnetic recording apparatus according to the first embodiment of the present invention. FIG. 3 is a perspective view showing a state when the suspension of the magnetic recording apparatus of the first embodiment is viewed from the magnetic disk side. 4A is a perspective view showing the piezoelectric sensor according to the first embodiment, and FIG. 4B is a cross-sectional view taken along the line AA in FIG. 4A. FIG. 5 is a cross-sectional view (part 1) illustrating the method for manufacturing the piezoelectric sensor according to the first embodiment. FIG. 6 is a cross-sectional view (part 1) illustrating the method of manufacturing the piezoelectric sensor according to the first embodiment. FIG. 7A is a perspective view showing a piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the second embodiment of the present invention, and FIG. 7B is cut along the line BB in FIG. 7A. It is sectional drawing when doing. FIG. 8A is a perspective view showing a piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the third embodiment of the present invention, and FIG. 8B is cut along the line CC in FIG. 8A. It is sectional drawing when doing. FIG. 9 is a cross-sectional view (part 1) illustrating the method of manufacturing the piezoelectric sensor according to the third embodiment. FIG. 10 is a cross-sectional view (part 2) illustrating the method of manufacturing the piezoelectric sensor according to the third embodiment. FIG. 11 is a cross-sectional view (part 3) illustrating the method of manufacturing the piezoelectric sensor according to the third embodiment. FIG. 12 is a cross-sectional view (part 4) illustrating the method of manufacturing the piezoelectric sensor according to the third embodiment. FIG. 13A is a perspective view showing a piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the fourth embodiment of the present invention, and FIG. 13B is cut along the line DD in FIG. 13A. It is sectional drawing when doing. 14A and 14B are perspective views showing other examples of the piezoelectric sensor attached to the suspension of the magnetic recording apparatus according to the embodiment of the present invention.

Explanation of symbols

10, 20 ... Magnetic recording device,
11, 21 ... casing,
12, 22 ... Magnetic disk,
13, 23 ... Magnetic head element,
14, 24 ... arm,
15, 25 ... suspension,
25a ... opening,
16, 26 ... control circuit part,
27, 40, 60, 80, 81, 82 ... piezoelectric sensor,
30, 50 ... Substrate (stainless steel substrate),
31, 51 ... insulating layer,
32, 52 ... lower electrode,
33, 53 ... Piezoelectric film,
34, 54 ... upper electrode,
35a, 35b, 55a, 55b ... wiring,
36, 74, 76 ... photoresist film,
56, 86 ... rod-shaped members,
71 ... Substrate (single crystal substrate).

Claims (5)

A magnetic recording medium;
A magnetic head element for writing or reading data on the magnetic recording medium;
A suspension for urging the magnetic head element toward the magnetic recording medium;
A piezoelectric sensor that is attached to the suspension and detects strain generated in the suspension;
An opening is provided in the suspension, and the piezoelectric sensor is attached to the suspension so as to cut through the opening. The piezoelectric sensor is
A substrate,
A first electrode formed on the substrate via an insulating film;
A piezoelectric film formed on the first electrode;
The magnetic recording apparatus according to claim 1, comprising a second electrode formed on the piezoelectric film.   The magnetic recording apparatus according to claim 2, wherein an opening is provided in a portion corresponding to the first electrode in the substrate of the piezoelectric sensor.   The magnetic recording apparatus according to claim 2, wherein the piezoelectric film of the piezoelectric sensor has a crystal orientation. In a suspension used in a magnetic recording device and biasing a magnetic head element toward a magnetic recording medium,
The suspension body,
An opening provided in the suspension body;
A suspension for a magnetic recording apparatus, comprising: a piezoelectric sensor attached to the suspension body so as to cut the opening vertically.

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