JP2016066393A - Work clamp jig and work-piece polishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work clamp jig and a work-piece polishing method which prevent decrease in accuracy of torsion in row-bar polishing a magnetic head element bent due to a difference between thermal expansion coefficients of a circuit layer and a ceramic layer.SOLUTION: Polishing is performed without correcting a curved surface of a work-piece 3 by bringing one clamp tool 5A into contact with a circuit layer (lower end part) of the work-piece 3 using an elastic material 21, and supporting the work-piece 3 so as to bring the other clamp tool 5B into contact with a curved surface of a ceramic layer of the work-piece 3 by a projection part 20 and reciprocating the work-piece in a surface plate radial direction while being in contact with a rotating surface plate.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a workpiece clamping jig and a workpiece polishing method capable of preventing a reduction in torsional accuracy due to residual stress generated during polishing of a magnetic head element.

  As shown in FIG. 4A, a magnetic head element used in a recent magnetic disk apparatus has a large number of works (also referred to as row bars) 3 arranged on a disk-shaped wafer 2 by a semiconductor manufacturing technique. The workpiece 3 manufactured and cut from the wafer 2 is firmly fixed to the workpiece fixture 4 as shown in FIG. 4B, and the workpiece 3 attached to the workpiece fixture 4 is gripped as shown in FIG. The magnetic head flying surface is polished by being pressed against the surface plate 6 rotating in the arrow D direction by the clamping jig 5 and reciprocating in the arrow E direction.

  In addition, as a document describing a technique related to a magnetic head machining apparatus according to the prior art, the following Patent Document 1 can be cited. Thus, a technique for relieving internal stress during polishing is described.

Japanese Patent Laid-Open No. 5-20643

  In the workpiece polishing method for the magnetic head element shown in FIG. 4, the workpiece 3 is polished while the workpiece 3 is slightly curved and the workpiece fixture 4 corrects the curvature. There was a problem that residual stress remained in the subsequent workpiece 3 and the torsional accuracy of several nanometers was lowered.

  Although the technique described in Patent Document 1 can relieve internal stress during polishing by a plurality of cuts provided on the air bearing surface of the workpiece, it is difficult to perform a plurality of cuts with high accuracy and There was a problem that internal stress during processing may remain on the workpiece.

  An object of the present invention is to solve the above-described problems caused by the prior art, and to provide a workpiece clamping jig and a workpiece polishing method capable of preventing a reduction in torsional accuracy due to residual stress.

In order to achieve the above object, the invention described in claim 1 is a work clamping jig for gripping a workpiece curved by a difference in thermal expansion coefficient between a ceramic layer and a circuit layer, wherein a screw hole is opened to remove the workpiece. A workpiece fixing tool held at the lower end, one clamp tool having a pair of elastic members that are open from the plane and have screw holes, the other clamp tool having a protrusion protruding from the center of the plane, the one and the other And a screw that passes through the screw hole of the workpiece fixing tool and fixes one and the other clamping tool, and supports the workpiece at a plurality of points by the one and the other protrusions, and the one clamping tool is used for the workpiece. It is configured to contact the circuit layer and to support the workpiece so that the other clamping tool contacts the curvature of the ceramic layer of the workpiece,
The invention described in claim 2 is characterized in that, in the workpiece clamping jig of the above feature, the projections that enable the plurality of configurations are point supports along the curvature of the workpiece.

According to a third aspect of the present invention, there is provided a work fixture for holding a work bent at a lower end by a difference in thermal expansion coefficient between a ceramic layer and a circuit layer and a pair of elastic members having a screw hole opened and projecting from a plane. One clamp tool having a material, the other clamp tool having a protrusion protruding from the center of the plane, and the one and the other clamp tool through the screw holes of the one and the other clamp tool and the work fixing tool. A work polishing method in which a work clamp jig provided with a fixing screw is used, and a lower end of the work clamp jig is polished by a rotating surface plate, wherein the work clamp jig is a circuit of a work piece. The workpiece is supported so that the other clamp is in contact with the curvature of the ceramic layer of the workpiece, and the plate is reciprocated in the radial direction of the platen while rotating the platen.
The invention according to claim 4 is characterized in that the plurality of projecting portions that enable the plurality of configurations are point supports along the curvature of the workpiece.

  The workpiece clamping jig and the workpiece polishing method according to the present invention support a workpiece such that one clamping tool is in contact with the circuit layer of the workpiece by an elastic material, and the other clamping tool is in contact with the curvature of the ceramic layer of the workpiece. By reciprocating in the radial direction of the platen while rotating, the polishing is performed without correcting the curvature of the workpiece. Therefore, no residual stress is generated by the correction, and a reduction in torsional accuracy can be prevented.

The figure which shows the assembly state of the workpiece clamp jig | tool by embodiment of this invention. The figure which shows the lower surface of the workpiece clamp jig | tool by this embodiment. The figure which shows the principle of the workpiece clamp jig | tool by this embodiment. The figure which shows the workpiece | work grinding | polishing method for magnetic head elements. The figure which shows the cross section of a workpiece | work.

Hereinafter, a workpiece clamping jig and a workpiece polishing method according to an embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1A, the workpiece clamping jig 5 according to the present embodiment includes a workpiece fixing tool 4 for holding a workpiece 3 having a screw hole opened and a circuit element (circuit layer) formed on the lower surface, and a screw. Clamping tool 5A having a pair of elastic members 21 (FIG. 3) that are open from the plane and projecting from a plane, Clamping tool 5B having a projection 20 (FIG. 3) that projects from the center of the plane, and the clamping tools 5A and 5B And a screw 7 that passes through the screw hole of the workpiece fixing tool 4 and fixes the clamping tools 5A and 5B. As shown in FIG. 1 (b), the lower end of the workpiece 3 is exposed from the bottom of the clamping tool 5A and 5B. It is assembled by screwing the screw 7 in a state of being sandwiched. Holding the workpiece 3 without being deformed by the protruding portion 20 in the sandwiched state is referred to as gripping in the present invention.

As shown in FIG. 2 showing the lower surface in the assembled state, the workpiece clamping jig 5 is configured such that the clamping tool 5B applies a pressing force that presses the central portion of the workpiece 3 toward the clamping tool 5A. As shown in FIG. 3 in which only the clamp tools 5A and 5B and the workpiece 3 are extracted and enlarged, the pressing force is obtained by the clamp tool 5A having the elastic material 21 protruding from the flat plane and the ceramic material protruding from the center of the flat plane. The workpiece 3 is sandwiched between the clamp tool 5B having the protruding portion 20 and the workpiece 3 is fixed in a state where no load is applied as much as possible by the three points ABC at both ends and the center position. The elastic material 21 has a flat shape when not in contact with the work 3 and is elastically deformed along the shape of the work 3 when pressed against the work 3.
In other words, the workpiece clamping jig 5 according to the present embodiment is configured to support the two positions and the center position of the workpiece 3 in a state where the curvature of the workpiece 3 is maintained.

  In the illustrated example, the elastic material 21 of the clamp tool 5A and the protruding portion 20 of the 5B support the workpiece 3 at three points. However, the present invention is not limited to the three-point support, and five or more points are supported. You may comprise so that it may be point-supported in the state which maintained the curvature of the workpiece | work 3 with the odd-numbered protrusion part.

  The wafer 2 is manufactured by growing a circuit layer including a magnetic head element on a ceramic layer by thin film growth using a semiconductor forming technique. For this reason, the curvature (warping) of the work 3 cut from the wafer 2 is shown in FIG. As shown in the cross section, it is known that when the thin film is grown, it is caused by a difference in thermal expansion coefficient between the ceramic layer 3B and the circuit layer 3A, and in the bending direction, the circuit layer extends and the ceramic layer contracts.

  For this reason, the workpiece clamping jig 5 according to the present embodiment uses the protrusion 20 and the elastic material 21 that allow a plurality of point contacts, the circuit layer side of the workpiece 3 is brought into contact with the clamp tool 5A, and the ceramic layer side is The curved workpiece 3 is supported by being brought into contact with the projection 20 of the clamp 5B.

  In the workpiece polishing method according to the present embodiment, the above-described workpiece clamping jig 5 is brought into contact with the circuit layer of the workpiece 3 by the projection 20 and the elastic material 21 that allow a plurality of point contacts, and the clamping tool 5B. In the state where the workpiece 3 is supported at three points so as to be in contact with the curvature of the ceramic layer of the workpiece 3, it operates to reciprocate in the radial direction of the platen while rotating the platen.

  Therefore, since the workpiece 3 polished according to the present embodiment is polished in a state in which the workpiece is allowed to be curved without correcting the curvature inherent in the workpiece 3, no residual stress is generated by the curvature correction, and the torsional accuracy is not generated. Can be prevented.

2 wafers, 3 workpieces, 3A circuit layer, 3B ceramic layer,
4 Work fixing tool, 5 Work clamp jig, 5A Clamp tool,
5B Clamping tool, 6 Surface plate, 7 Screw, 20 Projection, 21 Elastic material

Claims (4)

  A workpiece clamping jig for gripping a curved workpiece due to a difference in thermal expansion coefficient between a ceramic layer and a circuit layer, wherein a screw hole is opened to hold the workpiece at the lower end, and the screw hole is opened and protrudes from a plane. One clamp tool having a pair of elastic materials, the other clamp tool having a protrusion protruding from the center of the plane, the one and the other through the screw holes of the one and the other clamp tool and the work fixing tool A screw for fixing the clamp tool of the workpiece, the workpiece is supported at a plurality of points by the one and the other protrusions, one clamp tool is in contact with the circuit layer of the workpiece, and the other clamp tool is used to curve the ceramic layer of the workpiece. A workpiece clamping jig configured to support a workpiece in contact with the workpiece.   The workpiece clamping jig according to claim 1, wherein the projecting portions that enable the plurality of configurations point-support along the curvature of the workpiece.   A workpiece fixing tool that holds a workpiece curved at the lower end by a difference in thermal expansion coefficient between the ceramic layer and the circuit layer, and one clamp tool that has a pair of elastic members that are opened from the plane and protrude from the plane; Work clamp comprising: the other clamp tool having a protrusion protruding from the center of the plane; and the one and other clamp tool and a screw that passes through the screw hole of the work fix tool and fixes one and the other clamp tool. A workpiece polishing method using a jig and polishing the lower end of the workpiece clamp jig with a rotating surface plate, wherein the workpiece clamp jig is in contact with a circuit layer of the workpiece, and the other clamp tool is A work polishing method comprising: supporting a work so as to be in contact with the curvature of a ceramic layer of the work; and reciprocating in a radial direction of the surface plate while rotating the surface plate.   The workpiece polishing method according to claim 3, wherein the protrusions that enable the plurality of configurations perform point support along the curvature of the workpiece.

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