JP2010194692A - Surface plate and polishing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface plate improving polishing efficiency with respect to a treated surface of a treated material, and preventing occurrence of damage to or a scratch on the treated material; and a polishing device including the surface plate. <P>SOLUTION: An annular polishing surface 131 and a plurality of recesses 132 opening into the polishing surface 131 are formed in a lower surface plate 130. These recesses 132 are independently formed. The shape of an opening of each recess 132 is a substantially circular shape. The diameter of the opening of each recess 132 is 20 μm to 2 mm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a surface plate and a polishing apparatus.

  Conventionally, as processing for improving the flatness of the surface (surface to be processed) of an object to be processed such as a silicon wafer, polishing processing (lapping processing, polishing processing, etc.) for polishing the surface to be processed has been performed. This polishing process is performed using a surface plate having a polished surface. Specifically, while the polishing surface is pressed against the surface to be processed, a slurry-like abrasive (a liquid in which abrasive particles are suspended) is supplied between the polishing surface and the surface to be processed. This is done by rotating the surface plate in the circumferential direction. As a surface plate used in such a polishing process, one having a plurality of grooves formed on its polishing surface is known (for example, Patent Document 1).

  The surface plate described in Patent Document 1 includes a plurality of grooves formed in a grid pattern on a circular polished surface (a plurality of first grooves extending in the x-axis direction and a y-axis orthogonal to the axial direction). A plurality of second grooves extending in the direction are formed, and the plurality of grooves make it easy for the abrasive to penetrate between the polishing surface and the surface to be processed. However, in the surface plate provided with the polishing surface having such a configuration, the polishing efficiency is improved, while the corners of the plurality of block portions formed by the pair of adjacent first grooves and the pair of adjacent second grooves. The part (edge part) may cause scratches (scratches) on the surface to be processed or may damage the object to be processed.

JP 2003-109924 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a surface plate capable of preventing the processing object from being damaged and generating scratches while improving the polishing efficiency of the surface to be processed, and a polishing apparatus equipped with the surface plate. There is to do.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.
[Application Example 1]
The surface plate of the present invention has an annular polished surface,
A plurality of recesses opening in the polishing surface;
Each of the plurality of recesses is formed independently,
The opening shapes of the plurality of recesses are each substantially circular.
As a result, no protruding corners (edges) are formed on the polishing surface, so that it is possible to prevent the processing object from being damaged or scratching while improving the polishing efficiency of the processing object to the processing surface. A board can be provided. In addition, there is no anisotropy of the polishing ability, and the surface to be processed of the object to be processed can be similarly polished regardless of the direction in which the object passes through the recess. Therefore, the surface to be processed can be uniformly polished.

[Application Example 2]
In the surface plate of the present invention, the polishing surface has a first region located on the inner peripheral side, and a second region located outside the first region, and the first region includes the first region. It is preferable that an average opening diameter of the plurality of recessed portions formed is larger than an average opening diameter of the plurality of recessed portions formed in the second region.
Thereby, the difference of the polishing rate with respect to a to-be-processed surface can be made small between the inner peripheral side and the outer peripheral side of a polishing surface, and the whole surface of a to-be-processed surface can be grind | polished uniformly.

[Application Example 3]
In the surface plate of the present invention, the polishing surface has a first region located on the inner peripheral side, and a second region located outside the first region, and the first region includes the first region. The average depth of the plurality of recesses formed is preferably deeper than the average depth of the plurality of recesses formed in the second region.
Thereby, the difference of the polishing rate with respect to a to-be-processed surface can be made small between the inner peripheral side and the outer peripheral side of a polishing surface, and the whole surface of a to-be-processed surface can be grind | polished uniformly.

[Application Example 4]
In the surface plate of the present invention, the polishing surface has a first region located on the inner peripheral side, and a second region located outside the first region, the number of the recesses per 1 cm ² is preferably larger than the number of said recesses per 1 cm ² in the second region.
Thereby, the difference of the polishing rate with respect to a to-be-processed surface can be made small between the inner peripheral side and the outer peripheral side of a polishing surface, and the whole surface of a to-be-processed surface can be grind | polished uniformly.

[Application Example 5]
In the surface plate of the present invention, the polishing surface has a first region located on the inner peripheral side, and a second region located outside the first region, The occupation ratio of the recess is preferably higher than the occupation ratio of the recess in the second region.
Thereby, the difference of the polishing rate with respect to a to-be-processed surface can be made small between the inner peripheral side and the outer peripheral side of a polishing surface, and the whole surface of a to-be-processed surface can be grind | polished uniformly.

[Application Example 6]
In the surface plate of the present invention, it is preferable that each of the plurality of concave portions has a portion formed of a curved concave surface.
Thereby, the abrasive | polishing agent (abrasive microparticles | fine-particles) accommodated in the recessed part becomes easy to flow between a grinding | polishing surface and a to-be-processed surface from the inside of a recessed part. Therefore, a sufficient amount of abrasive can be supplied between the polishing surface and the surface to be processed, and the polishing efficiency of the surface to be processed is improved. Further, it is possible to eliminate the abrasive particles that remain in the recess for a long time, and it is possible to keep the diameters of the plurality of abrasive particles approximately equal to each other over time. For this reason, it is possible to effectively prevent the surface to be processed from being scratched or the object to be processed from being damaged during lapping.

[Application Example 7]
The polishing apparatus of the present invention comprises the surface plate of the present invention,
Holding means for holding the workpiece so as to come into contact with the polishing surface of the surface plate;
Abrasive supply means for supplying an abrasive between the workpiece and the surface plate;
It has the moving means which moves the said workpiece | work and the said grinding | polishing surface relatively.
Accordingly, it is possible to provide a polishing apparatus including a surface plate that can prevent the processing object from being damaged or scratched while improving the polishing efficiency of the processing object on the processing surface.

It is sectional drawing which shows 1st Embodiment of the grinding | polishing apparatus of this invention. FIG. 2 is a plan view of the polishing apparatus shown in FIG. 1. It is a top view of the lower surface plate with which the grinding | polishing apparatus shown in FIG. 1 is provided. It is sectional drawing of the lower surface plate shown in FIG. It is a top view of the lower surface plate with which the polisher concerning a 2nd embodiment of the present invention is provided. It is sectional drawing of the lower surface plate shown in FIG. It is a top view of the lower surface plate with which the polisher concerning a 3rd embodiment of the present invention is provided. It is a top view of the lower surface plate with which the polisher concerning a 4th embodiment of the present invention is provided.

Hereinafter, a surface plate and a polishing apparatus of the present invention will be described in detail based on embodiments shown in the accompanying drawings.
<First Embodiment>
First, a polishing apparatus (the polishing apparatus of the present invention) provided with the surface plate of the present invention will be described.
1 is a cross-sectional view showing a first embodiment of the polishing apparatus of the present invention, FIG. 2 is a plan view of the polishing apparatus shown in FIG. 1, and FIG. 3 is a plan view of a lower surface plate provided in the polishing apparatus shown in FIG. 4 is a cross-sectional view of the lower surface plate shown in FIG.

  In the following description, three directions orthogonal to each other in FIG. 1 are defined as an x-axis direction, a y-axis direction, and a z-axis direction. Of these, the polishing surface 131 of the lower surface plate 130 is the xy plane, and the normal direction of the polishing surface 131 is the z-axis direction. Hereinafter, the corresponding directions are the same in other drawings. Further, the upper side in FIG. 1 is referred to as “upper” and the lower side is referred to as “lower”. 3 and 4 are different from actual ones for convenience of explanation, such as the balance of the size of the lower surface plate and the recesses and the number of recesses.

The polishing apparatus 100 is an apparatus for polishing and flattening (mirroring) the upper surface and the lower surface of a workpiece (object to be processed) 10.
As shown in FIGS. 1 and 2, such a polishing apparatus 100 includes four carriers (holding means) 111, 112, 113, and 114 that support the workpiece 10, and an upper surface positioned above the carriers 111 to 114. A plate 120, a lower platen 130 positioned below the carriers 111 to 114, an upper platen support unit 140 driven by the rotation of the drive shaft 141, a sun gear 150 driven by the rotation of the drive shaft 151, and the drive shaft 161. Lower platen support 160 that is driven by rotation, internal gear 170 that is driven by rotation of the drive shaft 171, a suspension device 180 that suspends the upper platen 120 so as to be movable up and down, and abrasive supply that supplies abrasive A device 190 and a driving device (moving means) 200 are included.

As shown in FIG. 1, the four drive shafts 141, 151, 161, and 171 are formed as multiple shafts arranged concentrically, and from the inside, the drive shaft 141, the drive shaft 151, the drive shaft 161, and the drive shaft 171 are formed. It is arranged in the order. These four drive shafts 141, 151, 161, and 171 are independently rotatable around the Z axis.
At the upper end of the drive shaft 141, an upper surface plate support portion 140 is disposed. The upper surface plate support part 140 is engaged with the upper surface plate 120 when the upper surface plate 120 is disposed at the lower position by the operation of the suspension device 180.
A gear 142 is disposed at the lower end of the drive shaft 141. The gear 142 meshes with a gear 204 described later.

A sun gear 150 is disposed at the upper end of the drive shaft 151. The sun gear 150 is located below the upper surface plate support portion 140. The sun gear 150 has an annular shape provided concentrically with the upper surface plate support portion 140, and a gear portion 153 is formed on the outer periphery thereof.
A gear 152 is disposed at the lower end of the drive shaft 151. The gear 152 meshes with a gear 205 described later.

An internal gear 170 is disposed at the upper end of the drive shaft 171. The internal gear 170 is disposed so as to surround the periphery (outer periphery) of the sun gear 150. The internal gear 170 has an annular shape formed concentrically with the sun gear 150, and a gear portion 173 is formed on the inner periphery thereof.
A gear 172 is disposed at the lower end of the drive shaft 171. The gear 172 meshes with a gear 207 described later.

A lower surface plate support portion 160 is disposed at the upper end of the drive shaft 161. The lower surface plate support section 160 is disposed between the sun gear 150 and the internal gear 170 without meshing with these gears. The lower surface plate support portion 160 has an annular shape formed concentrically with the sun gear 150.
A lower surface plate 130 is disposed on the upper surface of the lower surface plate support 160. The lower surface plate 130 has an annular plate shape in plan view, and is provided with a polishing surface 131 on its upper surface. The lower surface plate 130 will be described in detail later.
A gear 162 is disposed at the lower end of the drive shaft 161. The gear 162 meshes with a gear 206 described later.

Four carriers (holding means) 111, 112, 113, 114 are provided between the sun gear 150 and the internal gear 170 and above the lower surface plate 130. As shown in FIG. 2, these four carriers 111, 112, 113, 114 are arranged at equiangular intervals (90 ° intervals) in the circumferential direction of the sun gear 150.
Next, the configuration of the carriers 111 to 114 will be described with reference to FIG. 2. Since the four carriers 111 to 114 have the same configuration, the carrier 111 will be representatively described, and the carriers 112 to 114 will be described. The description is omitted.

  As shown in FIG. 2, the carrier 111 has a disk shape. The carrier 111 has four holding holes 111 a penetrating in the thickness direction (z-axis direction) at equal angular intervals (90 ° intervals) along the circumferential direction of the carrier 111. The four holding holes 111 a have a circular shape corresponding to the shape of the workpiece 10 and are formed so that the diameter thereof is slightly larger than the diameter of the workpiece 10. The carrier 111 holds the workpiece 10 by fitting the workpiece 10 inside the holding hole 111a.

  A gear portion 111 b is formed on the outer periphery of the carrier 111, and the gear portion 111 b meshes with the sun gear 150 and the internal gear 170. Therefore, the carrier 111 revolves while rotating at a direction and a speed determined by the rotation direction and the rotation speed of the sun gear 150 and the internal gear 170 in conjunction with the rotation of the sun gear 150 and the internal gear 170.

Further, the thickness of the carrier 111 (the length in the z-axis direction) is slightly thinner than the thickness of the workpiece 10. Therefore, in a state where the carrier 111 holds the workpiece 10 by the holding hole 111a, the upper surface and the lower surface of the held workpiece 10 protrude from the upper surface and the lower surface of the carrier 111, respectively.
The constituent material of the carrier 111 is not particularly limited, and examples thereof include resin materials such as glass epoxy and vinyl chloride.

The workpiece 10 held by the carriers 111 to 114 is a plate having a circular shape in plan view. The shape of the workpiece 10 is not particularly limited. For example, the workpiece 10 may not have a plate shape, and the planar view shape may have a polygonal shape such as a triangle or a quadrangle.
The workpiece 10 is not particularly limited, and examples thereof include various glasses such as quartz glass and alkali-free glass, crystalline materials such as quartz, various ceramics such as alumina, silica, and titania, silicon, gallium arsenide, and the like. Various semiconductor materials, carbon materials such as diamond and graphite, polyethylene, polystyrene, polycarbonate, polyethylene terephthalate, liquid crystal polymer, phenol resin, acrylic resin and other dielectric materials such as plastic materials Examples include various metal materials such as aluminum, copper, and iron-based metals.

The suspension device 180 suspends and holds the upper surface plate 120 rotatably. The suspension device 180 has an upper position between the lower position where the upper surface plate 120 is engaged with the upper surface plate support portion 140 and the upper position where the engagement is released (the position shown in FIG. 1). The surface plate 120 can be moved up and down in the z-axis direction. Further, the suspension device 180 is configured to press the upper surface plate 120 against the workpiece 10 with a predetermined pressure when being in the lower position.
The upper surface plate 120 has an annular plate shape in plan view, and has a polishing surface 121 on its lower surface. The upper surface plate 120 is formed with a plurality of abrasive supply holes (not shown) penetrating in the thickness direction, and the abrasive supply pipes provided in the abrasive supply device 190 in the respective abrasive supply holes. 191 is connected. The upper surface plate 120 will be described in detail later.

A part of the abrasive supplied through the abrasive supply pipe 191 and the abrasive supply hole penetrates between the workpiece 10 and the upper surface plate 120, and a part thereof is formed on each of the carriers 111 to 114. Passing between the holding holes 111 a to 114 a and the workpiece 10, it penetrates between the workpiece 10 and the lower surface plate 130.
The abrasive supplied by the abrasive supply device 190 is not particularly limited, and examples thereof include a slurry in which abrasive fine particles (abrasive grains) are dispersed in, for example, an aqueous dispersion medium.

The abrasive fine particles are not particularly limited. For example, metal oxides such as cerium oxide (CeO ₂ ), manganese dioxide (MnO ₂ ), fumed alumina, colloidal alumina, and other metal oxides (Al ₂ O ₃ ), precipitation Examples thereof include silicon oxides (SiO ₂ ) such as silica, fumed silica and colloidal silica.
The average particle size of the abrasive fine particles can be appropriately set according to the type of workpiece 10 to be polished, the required processing speed, etc., but is preferably about 2 μm to 10 μm, and is about 5 μm. Is more preferable.

  The dispersion medium may be either aqueous or organic, or a mixture thereof. Here, examples of the organic dispersion medium include aromatics such as benzene, toluene, and xylene, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, alcohols such as butanol, isopropanol, ethanol, and methanol, ethyl cellosolve, and methyl. Examples include ethers such as cellosolve, esters such as ethyl acetate, methyl formate, ethyl formate, and methyl butyrate, and mixtures thereof. Examples of the aqueous dispersion medium include water.

The drive device 200 includes a drive motor 201 as a drive source, a gear box 202 that changes the rotation direction of the drive motor 201 to a right angle, an output shaft 203 that extends from the gear box 202, and the above-described fixed to the output shaft 203. 4 gears 204, 205, 206, and 207. Further, as described above, the gears 204, 205, 206, and 207 mesh with the gears 142, 152, 162, and 172, respectively.
When the drive motor 201 is operated, the drive shafts 141, 151, 161, and 171 are rotationally driven through the gear box 202, the output shaft 203, and the gears 204, 205, 206, and 207, respectively, and the upper surface plate 120, the sun gear 150, The lower surface plate 130 and the internal gear 170 are rotationally driven at a predetermined rotational speed and rotational direction.

Next, the upper surface plate 120 and the lower surface plate 130 will be described.
The surface plate of the present invention is a surface plate used when the workpiece 10 is polished. Here, the polishing of the workpiece 10 includes lapping for rough polishing and polishing for mirror polishing after the lapping. The surface plate of the present invention is a lapping surface plate used for lapping among these polishings.

The surface plate of the present invention can be applied to at least one of the upper surface plate 120 and the lower surface plate 130, but it is preferable to apply to both. In the present embodiment, a case where the surface plate of the present invention is applied to both the upper surface plate 120 and the lower surface plate 130 will be described.
Since the upper surface plate 120 has the same configuration as the lower surface plate 130 except that the above-described abrasive supply holes are formed, the lower surface plate 130 will be described as a representative, and the upper surface plate 120 will be described. Is omitted. 3 and 4, the upper side is referred to as "upper", the lower side as "lower", the left side as "left", and the right side as "right".

As shown in FIG. 3, the lower surface plate 130 has an annular plate shape in plan view. Further, the upper surface (surface on the workpiece 10 side) of the lower surface plate 130 constitutes an annular polishing surface 131.
Although it does not specifically limit as an internal diameter of the lower surface plate 130, It is preferable that it is about 300-500 mm. The outer diameter of the lower surface plate 130 is not particularly limited, but is preferably about 500 to 700 mm. The thickness of the lower surface plate 130 is not particularly limited, but is preferably about 20 to 50 mm.

  As shown in FIG. 3, the polishing surface 131 has a first region 131a located on the inner peripheral side and a second region 131b located so as to surround the outside of the first region 131a. Each of the first region 131a and the second region 131b has an annular shape concentric with the inner and outer periphery of the polishing surface 131. Further, the boundary (boundary line) between the first region 131a and the second region 131b is the inner periphery of the polishing surface 131, where R is the distance between the inner periphery and the outer periphery of the polishing surface 131 (the radial distance). It is preferable to pass through a point spaced about 1 / 3R to 2 / 3R in the radial direction. In the present embodiment, the boundary is set so as to pass through a point that is 1/2 R apart from the inner circumference of the polishing surface 131 in the radial direction.

  The lower surface plate 130 has a plurality of recesses 132 opened in such a polishing surface 131. In the following, for convenience of explanation, the recess 132 located in the first region 131a is also referred to as “first recess 132a”, and the recess 132 located in the second region 131b is also referred to as “second recess 132b”. . In addition, when “depressed portion 132” is simply described, it includes both the first recessed portion 132a and the second region 131b.

  Each recess 132 once accommodates (holds) an abrasive inside thereof, and thereafter, an appropriate amount of abrasive is placed between the polishing surface 131 and the lower surface 10a of the workpiece 10 (hereinafter also referred to as “surface to be processed 10a”). It has the function of supplying (penetrating) to By providing a plurality of recesses 132 having such a function on the polishing surface 131, the polishing efficiency of the surface to be processed 10a is improved. In addition, even if a plurality of recesses 132 are formed on the polishing surface 131, corners (corner portions of the respective blocks as in the prior art) are not formed on the polishing surface 131. Thus, it is possible to prevent the occurrence of scratches or the damage of the workpiece 10. That is, according to the surface plate of the present invention, it is possible to improve the polishing efficiency of the surface to be processed 10a while preventing the workpiece 10 from being damaged and the surface to be processed 10a from being scratched.

  Each of such recesses 132 is formed independently (that is, formed without communicating with the other recesses 132). Moreover, the opening shape of each recessed part 132 is substantially circular shape. As a result, the polishing surface 131 can obtain isotropic polishing characteristics (isotropic polishing is possible), and the surface to be processed no matter what direction the workpiece 10 passes over the recess 132. 10a can be polished in the same way (at the same polishing rate). Therefore, according to the polishing surface 131, the processing target surface 10a of the workpiece 10 can be uniformly polished.

The diameter (diameter) of each recess 132 is not particularly limited, but is preferably about 20 μm to 2 mm. Thereby, in particular, when the diameter of the abrasive fine particles in the abrasive is about 2 μm to 10 μm as described above (preferably 5 μm), a sufficient amount of the abrasive (abrasive fine particles) is accommodated in each recess 132. Can do. Therefore, the abrasive can be efficiently supplied from the inside of each recess 132 between the polishing surface 131 and the surface to be processed 10a.
In the present embodiment, the average opening diameter of the plurality of first recesses 132a is set larger than the average opening diameter of the plurality of second recesses 132b. Thereby, the whole area of the processing target surface 10a can be uniformly polished.

  Specifically, when the surface 10a to be processed of the workpiece 10 is polished using the above-described polishing apparatus 100 (by the carrier 111 holding the workpiece 10 revolving while rotating), the workpiece 10 is in the first region 131a. Since the moving speed (rotational speed) when passing through the second region 131b is slower than the moving speed when passing through the second region 131b, the polishing rate of the polishing surface 131 with respect to the processing surface 10a is higher than that in the first region 131a. Becomes lower than the second region 131b. Therefore, in order to increase the polishing rate of the first region 131a to the same level as the polishing rate of the second region 131b, the average opening diameter of the plurality of first recesses 132a is set to the average opening of the plurality of second recesses 132b. It was set larger than the aperture. As a result, the polishing rate for the surface to be processed 10a becomes substantially equal between the first region 131a and the second region 131b, and the entire surface of the surface to be processed 10a can be uniformly polished as described above.

  Although it does not specifically limit as an average opening diameter of the some 1st recessed part 132a, It is preferable that it is about 1 mm-2 mm. The average opening diameter of the plurality of second recesses 132b is not particularly limited, but is preferably about 20 μm to 200 μm. By using such a combination, the above-described effect becomes more remarkable (that is, the entire surface 10a can be polished more uniformly).

  As shown in FIG. 3, in the present embodiment, the diameter of the recess 132 gradually decreases from the inner periphery to the outer periphery of the polishing surface 131. In other words, the diameter of the recess 132 located near the boundary between the first region 131 a and the second region 131 b is smaller than the opening diameter of the recess 132 located near the inner periphery of the polishing surface 131, and It is larger than the opening diameter of the recessed part 132 located in the outer periphery vicinity. Thereby, the polishing rate can be gradually changed from the inner peripheral side of the polishing surface 131 toward the outer peripheral side.

  FIG. 4 is a cross-sectional view of the lower surface plate 130. As shown in the figure, each recess 132 is formed of a curved concave surface. As a result, the abrasive fine particles accommodated in the recess 132 can easily flow between the polishing surface 131 and the surface to be processed 10 a from the recess 132. Therefore, a sufficient amount of polishing fine particles (abrasive) can be supplied between the polishing surface 131 and the surface to be processed 10a, and the polishing efficiency for the surface to be processed 10a is improved.

  Further, when the concave portion 132 is formed of a curved concave surface, the abrasive fine particles staying in the concave portion 132 for a long time are eliminated (decreased). Here, the polishing agent supplied between the polishing surface 131 and the surface to be processed 10a from the above-described polishing agent supply device 190 is recovered after being discharged from the edge of the lower surface plate 130, for example, and is again supplied to the polishing agent supply device. 190 may be supplied between the polishing surface 131 and the surface to be processed 10a. In this case, the concave portion 132 is formed of a curved concave surface, and by eliminating the abrasive fine particles that remain in the concave portion 132 for a long time, all the abrasive fine particles are uniformly used for polishing, and the particle size distribution of the abrasive fine particles is changed over time. Can be kept constant. That is, even if the abrasive is reused and used repeatedly, the diameters of a large number of abrasive particles can be kept substantially equal, so that when the lapping is performed, scratches occur on the surface 10a to be processed, It is possible to effectively prevent breakage.

  Although it does not specifically limit as the depth (maximum depth) of each recessed part 132, It is preferable that it is about 10 micrometers-1 mm. Thereby, in particular, when the diameter of the abrasive fine particles in the abrasive is about 2 μm to 10 μm as described above (preferably 5 μm), a sufficient amount of the abrasive (abrasive fine particles) is accommodated in each recess 132. Can do. Therefore, it is possible to efficiently supply the abrasive between the polishing surface 131 and the surface to be processed 132 from within each recess 132.

Further, the number of recesses 132 formed per 1 cm ^{2 of} the polishing surface 131 is not particularly limited, but is preferably about 10 to 100. Thereby, since the abrasive | polishing agent accommodated in each recessed part 132 can be efficiently supplied to the whole area | region between the grinding | polishing surface 131 and the to-be-processed surface 10a, it is between the polishing surface 131 and the to-be-processed surface 10a. It is possible to effectively prevent the occurrence of a portion where no abrasive is present on the surface, and it is possible to prevent the surface to be treated 10a from being scratched or the workpiece 10 from being damaged. Furthermore, the polishing efficiency for the surface to be processed 10a is improved.

The occupation ratio of the plurality of recesses 132 with respect to the polishing surface 131 is not particularly limited, but is preferably about 20 to 80%. Thus, the abrasive contained in each recess 132 can be sufficiently supplied between the polishing surface 131 and the surface to be processed 10a, and the polishing efficiency for the surface to be processed 10a is improved.
A method for forming such a plurality of recesses 132 is not particularly limited. For example, various blasting processes in which an abrasive is sprayed onto the polishing surface 131 at a high speed and the impact surface is used to form the plurality of recesses 132 on the polishing surface 131. Alternatively, it is preferably formed by water jet processing in which a plurality of recesses 132 are formed on the polishing surface 131 by compressing water mixed with an abrasive to a high pressure and spraying the water onto the polishing surface 131. According to blast processing or water jet processing, it is possible to relatively easily form the minute-diameter concave portion 132 composed of a curved concave surface at a high density (or low density). Further, since the recess 132 is formed later on the polishing surface 131 which is a flat surface, the flatness of the polishing surface 131 can be made excellent.

  In addition, the constituent material of the lower surface plate 130 is not particularly limited. For example, various materials such as iron, nickel, cobalt, gold, platinum, silver, copper, manganese, aluminum, magnesium, zinc, lead, tin, titanium, tungsten, etc. Metals, alloys or intermetallic compounds containing at least one of these, ductile cast iron FCD400, FCD450, FCD700, cast iron such as gray cast iron FC400, FC450, and oxides, nitrides, carbides of these metals Etc. Among these, examples of alloys include stainless steel (for example, SUS303, SUS304, SUS316, SUS316L, SUS316J1, SUS316J1L, SUS318, SUS405, SUS430, SUS434, SUS444, SUS429, SUS430F, SUS302, etc.), Inconel, Copper, Hastelloy, Bronze, Hakuyo, Danko, Brass, Beryllium copper, Superelastic alloys (eg, Ni-Ti alloys, Ni-Al alloys, Cu-Zn alloys), cemented carbides (eg, tungsten carbide and cobalt are mixed) And other aluminum alloys such as duralumin.

Moreover, the manufacturing method of the lower surface plate 130 is not particularly limited, and examples thereof include casting, forging, and powder sintering (including the MIM method).
The polishing apparatus 100 as described above operates as follows.
First, the upper surface plate 120 and the lower surface plate 130 are fixed to the suspension device 180 and the lower surface plate support portion 160, respectively, with the suspension device 180 in the upper position. Next, the workpieces 10 are fitted into the holding holes 111a to 114a of the four carriers 111 to 114 (that is, in the present embodiment, a maximum of 16 workpieces 10 can be held). Operate to the lower position. As a result, the upper surface plate 120 and the upper surface plate support portion 140 are engaged, and the polishing surface 121 of the upper surface plate 120 is in press contact with the upper surface of each workpiece 10.

  In this state, the abrasive supply device 190 is operated, and between the work 10 upper surface and the polishing surface 121 and between the work 10 lower surface and the polishing surface 131 through the polishing agent supply hole formed in the upper surface plate 120. The abrasive is infiltrated and the drive motor 201 is operated to rotate the upper surface plate 120, the sun gear 150, the lower surface plate 130, and the internal gear 170 in a predetermined rotational speed and rotation direction, respectively. Then, as described above, the carriers 111 to 114 revolve while rotating, and the upper surface plate 120 and the lower surface plate 130 rotate in the circumferential direction, so that the workpiece 10 and the polishing surfaces 121 and 131 move relatively. . Thereby, the upper surface and the lower surface of the workpiece 10 are each polished.

<Second Embodiment>
Next, a second embodiment of the polishing apparatus of the present invention will be described.
FIG. 5 is a plan view of the lower surface plate provided in the polishing apparatus according to the second embodiment of the present invention, and FIG. 6 is a cross-sectional view of the lower surface plate shown in FIG. 5 and 6 are different from actual ones for convenience of explanation, such as the balance of the size of the lower surface plate and the recesses and the number of recesses.
Hereinafter, the polishing apparatus according to the second embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  The polishing apparatus according to the second embodiment of the present invention is the same as that of the first embodiment described above except that the configuration of the recesses formed on the upper surface plate and the lower surface plate is different. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above. The upper platen is the same as the lower platen except that the abrasive supply holes are formed. Therefore, the lower platen will be described as a representative, and the description of the upper platen will be omitted.

As shown in FIG. 5, the polishing surface 131 of the lower surface plate 130 is formed with a plurality of concave portions 132 having a substantially circular opening. The opening diameters of the plurality of recesses 132 are approximately equal to each other and are approximately 20 μm to 2 mm.
FIG. 6 is a cross-sectional view of the lower surface plate 130. As shown in the figure, in the present embodiment, the average depth (maximum depth) of the plurality of first recesses 132a is set deeper than the average depth of the plurality of second recesses 132b. According to such a polishing surface 131, the entire area of the processing target surface 10a can be uniformly polished.

  As described in the first embodiment, when the surface 10a to be processed of the workpiece 10 is polished using the polishing apparatus 100, the polishing rate for the surface 10a to be processed is higher in the first region 131a. It becomes lower than the area 131b. Therefore, in order to increase the polishing rate of the first region 131a to the same level as the polishing rate of the second region 131b, the average depth of the plurality of first recesses 132a is made larger than the average depth of the plurality of second recesses 132b. Also, the first region 131a was supplied with more abrasive (more per unit area) than the second region 131b. As a result, the polishing rate for the surface to be processed 10a becomes substantially equal between the first region 131a and the second region 131b, and the entire surface of the surface to be processed 10a can be uniformly polished as described above.

Although it does not specifically limit as an average depth of the some 1st recessed part 132a, It is preferable that it is about 0.5 mm-1 mm. The average depth of the plurality of second recesses 132b is not particularly limited, but is preferably about 10 μm to 100 μm. By using such a combination, the above-described effect becomes more remarkable.
In the present embodiment, the depth of the concave portion 132 gradually decreases from the inner periphery to the outer periphery of the polishing surface 131. In other words, the depth of the concave portion 132 located near the boundary between the first region 131a and the second region 131b is shallower than the depth of the concave portion 132 located near the inner periphery of the polishing surface 131. It is deeper than the depth of the recessed part 132 located in the outer periphery vicinity. Thereby, the polishing rate can be gradually changed from the inner peripheral side of the polishing surface 131 toward the outer peripheral side.
According to the second embodiment as described above, the same effect as that of the first embodiment can be exhibited.

<Third Embodiment>
Next, a third embodiment of the polishing apparatus of the present invention will be described.
FIG. 7 is a plan view of the lower surface plate provided in the polishing apparatus according to the third embodiment of the present invention. Note that FIG. 7 differs from an actual one for convenience of explanation, such as the balance of the size of the lower surface plate and the recesses and the number of recesses.
Hereinafter, the polishing apparatus according to the third embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  The polishing apparatus according to the third embodiment of the present invention is the same as that of the first embodiment described above except that the configuration of the recesses formed on the upper surface plate and the lower surface plate is different. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above. The upper platen is the same as the lower platen except that the abrasive supply holes are formed. Therefore, the lower platen will be described as a representative, and the description of the upper platen will be omitted.

As shown in FIG. 7, the polishing surface 131 of the lower surface plate 130 is formed with a plurality of recesses 132 having a substantially circular opening. The diameters of the recesses 132 are approximately equal to about 20 μm to 2 mm. Moreover, the depth (maximum depth) of each recessed part 132 is substantially equal, respectively, and is about 10 micrometers-1 mm.
In the present embodiment, the number of first recesses 132a per first region 131a and 1 cm ² is set to be larger than the number of second recesses 132b per ^second region 131b and 1 cm ² . According to such a polishing surface 131, the entire area of the processing target surface 10a can be uniformly polished.

As described in the first embodiment, when the surface 10a to be processed of the workpiece 10 is polished using the polishing apparatus 100, the polishing rate for the surface 10a to be processed is higher in the first region 131a. It becomes lower than the area 131b. Therefore, in order to increase the polishing rate of the first region 131a to the same level as the polishing rate of the second region 131b, the number of the first recesses 132a per 1 cm ² of the first region 131a is the second region. 131b was configured to be larger than the number of second recesses 132b per 1 cm ² . As a result, the polishing rate for the surface to be processed 10a becomes substantially equal between the first region 131a and the second region 131b, and the entire surface of the surface to be processed 10a can be uniformly polished as described above.

The number of the first region 131a, a first recess 132a per 1 cm ^2, is not particularly limited, preferably about 70 to 100 pieces. The number of the second recesses 132b per 1 cm ² of the second region 131b is not particularly limited, but is preferably about 10 to 30. By using such a combination, the above-described effect becomes more remarkable.
Further, in the present embodiment, the number of the recesses 132 per 1 cm ² of the polishing surface 131 is gradually reduced from the inner periphery to the outer periphery of the polishing surface 131. In other words, the number of recesses 132 per 1 cm ² of the polishing surface 131 near the boundary between the first region 131a and the second region 131b is the number of recesses 132 per 1 cm ² of the polishing surface 131 near the inner periphery. Is larger than the number of the recesses 132 per 1 cm ² of the polishing surface 131 in the vicinity of the outer periphery. Thereby, the polishing rate can be changed stepwise from the inner peripheral side to the outer peripheral side of the polishing surface 131.
According to the third embodiment as described above, the same effect as that of the first embodiment can be exhibited.

<Fourth embodiment>
Next, a fourth embodiment of the polishing apparatus of the present invention will be described.
FIG. 8 is a plan view of the lower surface plate provided in the polishing apparatus according to the fourth embodiment of the present invention. Note that FIG. 8 is different from the actual one for convenience of explanation, such as the balance of the size of the lower surface plate and the recesses and the number of recesses.
Hereinafter, the polishing apparatus according to the fourth embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

The polishing apparatus according to the fourth embodiment of the present invention is the same as that of the first embodiment described above except that the configuration of the recesses formed on the upper surface plate and the lower surface plate is different. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above. The upper platen is the same as the lower platen except that the abrasive supply holes are formed. Therefore, the lower platen will be described as a representative, and the description of the upper platen will be omitted.
As shown in FIG. 8, the diameters of the plurality of recesses 132 are different from each other. The diameter of each concave portion 132 is not particularly limited, but is preferably about 20 μm to 2 mm.

In the present embodiment, the occupation ratio of the first recess 132a in the first region 131a is set higher than the occupation ratio of the second recess 132b in the second region 131b. According to such a polishing surface 131, the entire area of the processing target surface 10a can be uniformly polished.
As described in the first embodiment, when the surface to be processed 10a of the workpiece 10 is polished using the polishing apparatus 100, the polishing rate for the surface to be processed 10a is higher in the first region 131a. It becomes lower than the area 131b. Therefore, in order to increase the polishing rate of the first region 131a to the same level as the polishing rate of the second region 131b, the occupancy rate of the first recess 132a in the first region 131a is the second region 131b. The occupancy rate of the second recess 132b is set higher. As a result, the polishing rate for the surface to be processed 10a becomes substantially equal between the first region 131a and the second region 131b, and the entire surface of the surface to be processed 10a can be uniformly polished as described above.

The occupation ratio of the first recess 132a in the first region 131a is not particularly limited, but is preferably 60% to 80%. Further, the occupation ratio of the second recess 132b in the second region 131b is not particularly limited, but is preferably 20% to 40%. Thereby, the above-mentioned effect becomes more remarkable.
In the present embodiment, the occupancy ratio of the recess 132 with respect to the polishing surface 131 decreases from the inner periphery to the outer periphery of the polishing surface 131. In other words, the occupation ratio of the recess 132 with respect to the polishing surface 131 near the boundary between the first region 131a and the second region 131b is lower than the occupation ratio of the recess 132 with respect to the polishing surface 131 near the inner periphery. It is higher than the occupation ratio of the recess 132 with respect to the polishing surface 131 in the vicinity. Thereby, the polishing rate can be changed stepwise from the inner peripheral side to the outer peripheral side of the polishing surface 131.
According to the fourth embodiment as described above, the same effect as that of the first embodiment can be exhibited.

  As described above, the surface plate and the polishing apparatus of the present invention have been described based on the illustrated embodiments. However, the present invention is not limited to these, and the configuration of each part is an arbitrary configuration having the same function. Can be substituted. Moreover, other arbitrary structures and processes may be added. Further, the surface plate of the present invention may be a combination of any two or more configurations (features) of the above-described embodiments. That is, for example, the depth of the concave portion may be continuously decreased while the diameter of the concave portion is continuously reduced from the inner peripheral side to the outer peripheral side of the polishing surface.

In the above-described embodiment, the polishing apparatus for polishing both surfaces of the workpiece has been described. However, the present invention is not limited to this, and is configured to polish only one of the upper surface and the lower surface of the workpiece. Also good.
In the above-described embodiment, the concave portion formed on the polishing surface of the upper surface plate and the concave portion formed on the polishing surface of the lower surface plate are described as having the same configuration, but the present invention is not limited thereto. For example, the lower surface plate of the first embodiment described above and the upper surface plate of the second embodiment described above may be combined. That is, the groove formed on the polishing surface of the upper surface plate and the groove formed on the polishing surface of the lower surface plate may have different configurations.
In the above-described embodiment, the surface plate of the present invention is applied to the upper surface plate and the lower surface plate. However, the present invention is not limited to this. For example, the present invention is applied to only one of the upper surface plate and the lower surface plate. The surface plate may be applied.

  DESCRIPTION OF SYMBOLS 10 ... Work 10a ... Surface to be treated 100 ... Polishing apparatus 111-114 ... Carrier 111a-114a ... Holding hole 111b ... Gear part 120 ... Upper surface plate 121 ... Polishing surface 130 ... Lower surface plate 131 …… Polished surface 131a …… first region 131b …… second region 132 …… concave portion 132a …… first concave portion 132b …… second concave portion 140 …… upper surface plate support portion 141 …… drive shaft 142 ... Gear 150 ... Sun gear 151 ... Drive shaft 152 ... Gear 153 ... Gear portion 160 ... Lower surface plate support portion 161 ... Drive shaft 162 ... Gear 170 ... Internal gear 171 ... Drive shaft 172 ... ... gear 173 ... gear section 180 ... suspension device 190 ... abrasive supply device 191 ... abrasive supply tube 200 ... drive device 201 ... drive Motor 202 ...... gearbox 203 ...... output shaft 204-207 ...... gear

Claims (7)

An annular polished surface;
A plurality of recesses opening in the polishing surface;
Each of the plurality of recesses is formed independently,
An opening shape of the plurality of concave portions is a substantially circular shape, respectively.   The polishing surface has a first region located on the inner peripheral side and a second region located outside the first region, and the plurality of recesses formed in the first region. The surface opening according to claim 1, wherein the average opening diameter is larger than the average opening diameter of the plurality of recesses formed in the second region.   The polishing surface has a first region located on the inner peripheral side and a second region located outside the first region, and the plurality of recesses formed in the first region. 2. The surface plate according to claim 1, wherein the average depth is deeper than the average depth of the plurality of recesses formed in the second region. The polishing surface has a first region located on the inner peripheral side and a second region located outside the first region, and the recesses per 1 cm ² in the first region. The surface plate according to claim 1, wherein the number is larger than the number of the concave portions per 1 cm ² in the second region.   The polishing surface has a first region located on the inner peripheral side and a second region located outside the first region, and the occupation ratio of the recesses in the first region is: The platen according to claim 1, wherein the surface area is higher than an occupation ratio of the concave portion in the second region.   The surface plate according to any one of claims 1 to 5, wherein each of the plurality of concave portions has a portion formed of a curved concave surface. A surface plate according to any one of claims 1 to 6,
Holding means for holding the workpiece so as to come into contact with the polishing surface of the surface plate;
Abrasive supply means for supplying an abrasive between the workpiece and the surface plate;
A polishing apparatus comprising a moving means for relatively moving the workpiece and the polishing surface.

Images