JPH0611960U - Lap surface plate - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to process a work piece with high precision by lapping. [Constitution] In a lapping plate made of a combination of different materials having different thermal expansion coefficients, the adhesive has Young's modulus E = 0.3.
It is configured to have a thickness of 1 mm by using 5 kgf / mm ² .

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a lapping plate applied to lapping highly brittle materials such as semiconductor, optical, magnetic and electronic materials, and relates to a lapping plate designed to accurately lapping highly brittle materials.

[0002]

[Prior art]

 Conventionally, lapping is known as high-precision machining of magnetic heads and the like. Lapping is performed by dropping the lapping liquid containing abrasive grains onto the rotationally driven lapping plate, mounting the workpiece, and rocking the lapping plate so that the lapping between the lapping plate and the workpiece. The polishing is performed by the lapping liquid supplied to the. In this lapping, the surface shape of the lap surface plate is transferred as it is to the workpiece, so there is a close relationship between the surface shape of the lapping surface plate and the processing accuracy.

A conventional lapping plate uses granite or a soft metal as a lapping plate, and has a structure in which a lower plate is combined in order to connect with a driving unit that rotationally drives the lapping plate. The lap face plate and the lower plate are made of different materials.

[0004]

[Problems to be solved by the device]

 In the lap surface plate, in which the lap face plates of different materials having different thermal expansion coefficients are joined to the lower plate rotatably attached, a temperature rise occurs due to the polishing heat generated in the lapping and the heat generated by the driving source. Due to the difference in thermal expansion between the lap face plate and the rotatably attached lower plate, when the amount of thermal expansion of the lap face plate is larger than the amount of thermal expansion of the lower plate, the lap face plate surface is deformed to be convex, When the amount of thermal expansion of the lap face plate is smaller than the amount of thermal expansion of the lower plate, deformation occurs in which the surface of the lap face plate is concave. That is, the flatness of the lapping plate changes under the influence of the temperature change of the lapping plate.

For example, the lap face plate 1 shown in FIG. 1 has an outer diameter of 300 mm, an inner diameter of 60 mm, a thickness of 50 mm, a coefficient of linear expansion α ₁ of 9 × 10 ⁻⁶ / ° C., and a Young's modulus of 10 × 10 ⁴ k. used as gf / mm ² made of granite, the lower plate 2 to shape the outer diameter [phi] 300 mm, and a thickness of 10 mm, the linear expansion coefficient alpha ₂ is 22 × 10 ^-6 / ℃, Young's modulus of 6.8 × 1 0 An aluminum material of ³ kgf / mm ² was used as a material for the adhesive agent for bonding the lap face plate 1 and the lower plate 2 with a linear expansion coefficient α ₃ of 16 × 10 ^-5 / ° C and a Young's modulus of 8 kgf / In a lapping plate using a mm ² epoxy adhesive with a thickness of 1 mm, the flatness of the lapping plate 1 changes by about 2 μm / ° C as shown in Fig. 3 due to the temperature rise during lapping. Object 4 cannot be machined to a certain size, and the flatness is also more than There was a problem with the lapping accuracy, such as not being able to raise it further.

In consideration of the above problems, the present invention makes it possible to process a workpiece with high accuracy without changing the surface shape of the lapping plate even when the temperature of the lapping plate changes. The purpose is to provide a lap plate that has

[0007]

[Means for Solving the Problems]

The lapping plate of the present invention is formed by combining different kinds of materials having different thermal expansion coefficients. In the lapping plate, Young's modulus E = 0.1 kgf / mm ^{2 to} 0. An adhesive of 4 kgf / mm ² is used, and an elastic buffer band is provided so that the adhesive has a thickness of 1 mm to 10 mm, and the adhesive is attached.

[0008]

[Action]

When the temperature of the lapping plate rises during lapping, different materials having different coefficients of thermal expansion expand by different amounts, and Young's modulus E = 0.1 kgf / mm ² ~ provided between the different materials with a thickness of 1 mm to 10 mm. An adhesive having 0.4 kgf / mm ² is elastically deformed by being applied with tension due to thermal expansion, but the Young's modulus of the adhesive provided between different materials is E = 0.1 kgf / mm ^{2 to} 0.4 kgf / mm ^{2. Since} it is as small as ² , elastic deformation is performed without restraining different materials, so changes in the surface shape of the lapping plate are suppressed and the flatness of the lapping plate is maintained.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, below the flat-finished lap face plate 1 having a through hole, there is a lower plate 2 having a through hole in the center, and fixed with an adhesive 3 having a thickness to form a lower plate. The bolt 2 is fixedly supported on the spindle 5 using bolts 6.

In the present embodiment, the lap face plate 1 has a shape of outer diameter φ300 mm, inner diameter φ60 mm, thickness 50 mm, and is made of granite. The linear expansion coefficient α of this granite is used. ₁ Is 9 × 10^-6/ ° C, Young's modulus is 10 × 10^Fourkgf / mm²Is. The lower plate 2 has an outer diameter of 300 mm, a thickness of 10 mm, and a through hole of 11 mm in the center, and the material is made of aluminum. The linear expansion coefficient α of this aluminum is₂Is 22 × 10^-6/ ° C, Young's modulus is 6.8 × 10³kgf / mm²Is. Further, as a material of the adhesive 3 for bonding the lap face plate 1 and the lower plate 2, a linear expansion coefficient α₃Is 16 × 10^-Five/ ° C, Young's modulus is 0.35 kgf / mm²Elastic adhesive of 2 mm thickness was used. The lower plate 2 is fixed to and supported by the spindle 5 with M6 bolts 6.

When the workpiece 4 is provided on the lap face plate 1 and the lap face plate 1 is rotated in the direction of arrow 8 at a rotation speed of 49 rpm, the workpiece 4 is rotated in the direction of arrow 9 by the rotational force of the lap face plate 1. . In this state, when a lap liquid containing abrasive grains is dropped onto the lap face plate 1 which rotates in the direction of the arrow 8, the abrasive grains roll between the lap face plate 1 and the work piece 4, and the work piece is processed. Polish 4.

At this time, the lap surface plate is affected by the polishing heat generated between the upper surface of the lap face plate 1 and the workpiece 4 and the heat generated by the motor (not shown) of the rotary drive unit. It causes a temperature change. Under the influence of these heats, the lap face plate 1 and the lower plate 2 were at 23 ° C. and 24 ° C. before lapping, respectively, but the temperature was increased to 29 ° C. and 28 ° C. in the lapping time of 30 minutes, respectively. Due to this temperature rise, the lap face plate 1 and the lower plate 2 cause thermal expansion, but since the linear expansion coefficients are different, the thermal expansion amount is different. In this case, since the linear expansion coefficient of aluminum used for the lower plate 2 is larger than the linear expansion coefficient of granite used for the lap face plate 1, the thermal expansion amount of the lower plate 2 becomes large and the lap face plate 1 In the structure in which the lower plate 2 and the lower plate 2 are bonded together with the adhesive 3, the lower surface of the lap face plate 1 is deformed by the amount of thermal expansion of the lower plate 2, so that the upper surface of the lap face plate 1 has a concave shape. By using an elastic adhesive having a Young's modulus of 0.35 kgf / mm ² with a thickness of 2 mm for the face plate 1 and the lower plate 2, this adhesive layer absorbs the difference in the amount of thermal expansion, and the flatness of the lap face plate 1 is Even after the temperature rises, it is the same as before wrapping. As a result, the work piece 4 can be machined to a certain size with high accuracy, and the flatness of the work piece can be increased. Incidentally, FIG. 2 shows the relationship between the temperature of the lapping plate of the above-described embodiment and the flatness of the lapping plate 1. In the above example, the flatness change rate with temperature of the lap face plate 1 is 0.07 μm / ° C.

Further, in the above-mentioned embodiment, when the thickness of the adhesive 3 is 1 mm, the flatness change rate due to the temperature of the lap face plate 1 is 0.15 μm / ° C. In this case also, the lap platen at the time of lapping is used. The increase in the temperature does not affect the flatness change of the lap face plate 1, and the work piece 4 can be machined to a certain size with high accuracy, and the flatness of the work piece can be increased. Became possible.

As is clear from the above comparison, the lapping plate of the above-described embodiment enables extremely high-precision lapping as compared with the conventional lapping plate.

In the above embodiment, granite was used as the material of the lap face plate 1 and aluminum was used as the material of the lower plate 2. However, the present invention is not limited to this, and the material of the lap face plate 1 and the lower plate 2 is not limited to this. Various materials such as cast iron, mild steel, copper, tin, ceramics and resins may be applied.

Further, although two kinds of combinations of the lap face plate 1 and the lower plate 2 are used in the above embodiment, the present invention is not limited to this, and combinations of three kinds and four kinds of different materials may be used.

Further, in the above embodiment, the shape of the lap face plate 1 has an outer diameter of φ300 mm, an inner diameter of φ60 mm and a thickness of 50 mm, and the lower plate 2 has an outer diameter of φ300 mm and a thickness of 10 mm. However, the present invention is not limited to this.

[0018]

[Effect of device]

In a lapping plate made of a combination of different materials having different thermal expansion coefficients, a bonding agent having Young's modulus E = 0.1 kgf / mm ^{2 to} 0.4 kgf / mm ² was used for the bonding method. By using a lapping plate that is laminated to have a thickness of 1 mm to 10 mm, it is possible to eliminate warpage due to thermal expansion due to the temperature rise of the lapping plate during lapping, and to machine the work piece to a certain size with high accuracy. It is possible to increase the flatness of the work piece.

[Brief description of drawings]

FIG. 1 is a schematic view of a lap surface plate showing an embodiment of the present invention.

FIG. 2 is a diagram showing a change in flatness according to temperature of a lapping plate showing an embodiment of the present invention.

FIG. 3 is a diagram showing a change in flatness of a conventional lap face plate due to temperature.

[Explanation of symbols]

 1 Lap face plate 2 Lower plate 3 Adhesive 4 Workpiece 5 Spindle 6 Bolt

Claims (1)

[Scope of utility model registration request] 1. A lapping plate constituted by joining materials having different thermal expansion coefficients, the joining being performed by Young's modulus E = 0.
1kgf / mm ² ~0.4kgf / mm ² the adhesive used is, lap plate, characterized in that the thickness of the adhesive and 1 mm to 10 mm.