JP4097356B2 - Flat plate chuck base, flat plate polishing apparatus and flat plate polishing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a flat plate chuck base for chucking in order to polish a flat plate surface.ThePolishing device for polishing flattened flat plate surfaceAnd flat plate polishing methodAbout.
[0002]
[Prior art]
The position of the retainer that holds the wafer and the position of the wafer surface is set to a predetermined positional relationship (the surface of the retainer protrudes to the polishing surface side by about tens of microns from the wafer surface), and the wafer surface is properly polished. To do. For this setting, when a shim is inserted between the retainer and the chuck base on which the wafer is placed, the conditions fluctuate due to a deviation in the thickness of the wafer, and the in-plane uniformity of the polished wafer is increased. It is difficult to maintain accuracy.
[0003]
Therefore, in the conventional wafer chuck table, instead of inserting the shim, the retainer and the chuck part for chucking the wafer are structured to be movable independently of the wafer chuck table and the polishing pad, respectively, and the pressure of the retainer and the chuck part is set. By independently adjusting the pressures, the pressure acting on the retainer can be changed relative to the pressure acting on the chuck portion.
[0004]
By appropriately adjusting the biasing force acting on the retainer with respect to the biasing force acting on the chuck portion, the polishing pad can perform optimum polishing of the peripheral region of the wafer.
[0005]
[Problems to be solved by the invention]
According to the wafer chuck table as described above, since only the pressure is controlled, it is difficult to maintain the positional relationship between the retainer and the wafer at a predetermined condition.
[0006]
  Accordingly, the present invention provides a flat plate chuck table capable of easily maintaining the positional relationship between the retainer and the flat plate to be polished, and a flat plate polishing apparatus using the flat plate chuck table.And flat plate polishing methodThe purpose is to provide.
[0007]
[Means for Solving the Problems]
  In order to achieve the above object, a flat plate chuck base according to the present invention is connected to a chuck portion 12 having a chuck surface 36 for chucking the flat plate 13 and the chuck portion 12 as shown in FIG. A first cylinder 15A having a first piston 17A inside, and a first chamber 16A communicating with the first cylinder 15A via a first restrictor 21A, the first cylinder 15A, The inside surrounded by the cylinder 15A and the first piston 17A and the inside of the first chamber 16A are configured to be accommodated in the first fluid.
  The flat plate chuck base according to the present invention is a chuck for chucking a flat plate.A chuck portion having a surface, a first cylinder having a slidable first piston connected to the chuck portion and forming a chamber, and a through-hole formed in a lower surface of the first cylinder A piston rod that connects the chuck portion and the first piston, a first chamber that forms a communication chamber with the first cylinder, the first cylinder, and the first chamber; And a first communication passage provided with a first throttle in the middle, and an interior of the first cylinder surrounded by the first cylinder and the first piston, and the first Configured to contain the first fluid within the chamber ofIt is characterized by that.
[0008]
If comprised in this way, since a 1st cylinder, a 1st piston, and a 1st aperture_diaphragm | restriction are provided, the plane plate chuck stand which chucked the plane plate will descend | fall, for example at the time of surface-finding, and a plane plate When the polishing surface of the surface plate for polishing the surface comes into contact with the surface to be polished of the flat plate, the first piston moves inside the first cylinder relative to the first chuck table in the direction of the chuck table. . The movement of the first piston in this direction causes the plane plate to move in the same direction as the first piston. Further, the movement of the first piston pushes the first fluid in the direction of the first orifice.
[0009]
The first fluid pushed by the first piston passes through the first throttle and further moves to the first chamber, thereby absorbing and mitigating the impact caused by the contact with the polishing surface of the flat plate. it can. This is because the damper effect can be obtained when the first fluid passes through the first restrictor, so that the movement of the first piston (planar plate) can be absorbed smoothly. Further, the first piston and the first cylinder may be in a sliding relationship, and may be connected to each other via, for example, a bellows or an elastic film.
[0010]
  BookThe flat plate chuck base according to the invention is:AboveIn the flat plate chuck base, the first fluid is pressurized and sealed in the first cylinder and the first chamber.
[0011]
Since the first fluid is pressurized and sealed in the first cylinder and the first chamber, the first cylinder and the first chamber do not cause a large pressure fluctuation, and the flat plate Such impact and vibration of the flat plate can be stably reduced and suppressed. Since the first fluid is sealed, even if it is necessary to supply the first fluid from the outside to the first chamber, the supply is not frequent. Is less likely to enter.
[0012]
  BookThe flat plate chuck base according to the invention is:AboveIn the flat plate chuck table, the first fluid contains a liquid, the liquid is filled in the first cylinder, and further filled so as to reach at least the first throttle. .
[0013]
Since the liquid is filled to reach at least the first throttle, the first piston pushes the liquid, the liquid passes through the first throttle and enters the first chamber. Therefore, the damper effect is further enhanced, and the impact due to the contact of the flat plate and the vibration during polishing of the flat plate can be absorbed more smoothly.
[0014]
  BookThe flat plate chuck base according to the invention is:AbovePressure measuring means for measuring the pressure of the first fluid;,And pressure adjusting means for adjusting the pressure to be a predetermined value based on the measured pressure.
[0015]
The pressure of the fluid can be adjusted by the pressure adjusting means so that the flat plate is most appropriately polished.
[0016]
The pressure adjusting means feeds back the pressure difference between the detected pressure and the target pressure with respect to the flat plate chuck table lifting / lowering adjusting means provided in the flat plate polishing apparatus so that the fluid pressure becomes a predetermined value. You may adjust a pressure by raising / lowering a flat board chuck | zipper stand to an raising / lowering adjustment means.
[0017]
  BookThe flat plate chuck base according to the invention is:AboveA retainer disposed around the flat plate held by the chuck portion;,A second cylinder having therein a second piston connected to the retainer;,A second chamber communicating with the second cylinder via a second throttle,The inside of the second cylinder surrounded by the second cylinder and the second piston and the inside of the second chamber are configured to store the second fluid.
[0018]
For example, at the time of chamfering, the flat plate comes into contact with the polished surface and collides, the first piston moves, the first fluid in the first cylinder passes through the first throttle, and the first piston is caused by the damper effect. Absorbs vibration. Similarly, for example, when chamfering, the retainer comes into contact with the polishing surface and collides, the second piston moves, the second fluid in the second cylinder passes through the second throttle, and the second effect is generated by the damper effect. The vibration of the piston is absorbed. Thereby, the positional relationship between the retainer and the flat plate is prevented from abruptly changing, and also serves to help alleviate the contact impact of the flat plate on the polishing surface.
[0019]
It is preferable that the second fluid is pressurized and sealed inside the second cylinder and the second chamber. The second fluid may include a liquid, and the liquid may be filled inside the second cylinder and further filled so as to reach at least the second throttle.
[0020]
  According to the inventionFlat plate polishing equipmentAboveFlat plate chuck base and,A surface plate having a polishing surface for polishing the flat plate is provided.
  A flat plate polishing method according to the present invention is a flat plate polishing method in which a flat plate chucked on the above-described flat plate chuck table is rotated and polished by a surface plate having a polishing surface. The flat plate is polished by the polishing surface while the flat plate chuck table absorbs the shock of the above and the vibration of the flat plate accompanying rotation is absorbed by the flat plate chuck table.
[0021]
Since the impact between the flat plate and the polishing surface or the impact between the flat plate and the polishing surface of the retainer can be alleviated at the time of chamfering, it is not necessary to slow down the lowering speed of the flat plate chuck base. Further, since the vibration of the flat plate or the vibration of the flat plate and the retainer at the time of polishing can be absorbed, the flat plate can be polished satisfactorily.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1A is a schematic cross-sectional view showing a flat plate polishing apparatus 1 according to an embodiment of the present invention. The flat plate polishing apparatus 1 has a chuck base 11 as a flat plate chuck base. The chuck base 11 has a disk-shaped holding plate 12 as a chuck portion at the lower part in the vertical direction, and a disk-shaped flat plate 13 is placed on the chuck surface 36 of the holding plate 12 by a vacuum suction method. The chuck base 11 has an annular retainer 14 disposed so as to surround the holding plate 12 in the horizontal direction. A surface plate 24 having a polishing surface 23 facing the flat plate 13 on the upper surface is disposed below the flat plate 13.
[0023]
The chuck base 11 is processed with a cylindrical first cylinder 15A and a cylindrical first chamber 16A disposed above the first cylinder 15A in alignment with the center line. A disc-shaped first piston 17A is incorporated in the first cylinder 15A so as to be slidable in the vertical direction. The outer diameter of the first piston 17A is slightly smaller than the inner diameter of the first cylinder 15A.
[0024]
As shown in FIG. 1B, an O-ring groove 25 is formed in the outer peripheral portion of the side surface of the first piston 17A, and an O-ring 26 is fitted therein. The O-ring 26 is formed inside the first cylinder 15A. Is kept airtight and slides along the inner periphery of the first cylinder 15A. Therefore, the first fluid (for example, gas such as air or nitrogen gas) in the first cylinder 15A leaks practically from between the first piston 17A and the sliding surface of the first cylinder 15A. There is no. A seal portion including the O-ring groove 25 and the O-ring 26 is configured to keep the inside of the first cylinder 15A airtight. A plurality of O-rings 26 may be provided on the outer periphery of the side surface of the first piston 17A. It is good also as a seal part comprised including an O ring and a cap seal.
[0025]
Returning to FIG. 1A, the description will be continued. The first lower wall 33A between the lower surface 31 of the chuck base 11 and the first lower surface 32A of the first cylinder 15A has four (or five or more) first through holes 34A. Four first piston rods 35A (the same number as the first through holes 34A) that are processed and connect the holding plate 12 and the first piston 17A through the first through holes 34A are arranged. Yes. The first piston rod 35A is vertically connected to the first piston. The first piston slides in the longitudinal direction of the first piston rod 35A.
[0026]
The chuck base 11 is processed with a first communication path 20A that communicates the first cylinder 15A and the first chamber 16A, and a first diaphragm is provided at a position approximately in the middle of the first communication path 20A. The first orifice 21A is provided.
[0027]
The chuck base 11 is processed with a first fluid supply path 22A (partially shown, partly indicated by a straight line, partly omitted) communicating with the first chamber 16A, in the middle of the first fluid supply path 22A. Is connected to a pressure indicating transmitter PIT. A first gate valve (not shown) is provided at the tip of the first fluid supply path 22A, and a first fluid supply port (not shown) is provided at the tip. During polishing, the first gate valve is closed, and no inflow / outflow of fluid occurs.
[0028]
The chuck base 11 is processed with an annular second cylinder 15B and an annular second chamber 16B disposed above the second cylinder 15B in alignment with the center line to form a chamber. An annular second piston 17B is incorporated in the second cylinder 15B so as to be slidable in the vertical direction. The outer diameter of the second piston 17B is slightly smaller than the outer diameter of the inner wall of the second cylinder 15B, and the inner diameter of the second piston 17B is slightly smaller than the inner diameter of the inner wall of the second cylinder 15B. Big.
[0029]
As shown in FIG. 1C, an outer O-ring groove 27 is formed in the outer peripheral portion of the side surface of the second piston 17B, an outer O-ring 28 is fitted, and an inner O-ring groove is inserted in the inner peripheral portion of the side surface. 29 is formed, and the inner O-ring 30 is fitted. The outer O-ring 28 and the inner O-ring 30 keep the inside of the second cylinder 15B airtight, and slide on the outer peripheral portion and the inner peripheral portion of the second cylinder 15B, respectively. Therefore, the second fluid inside the second piston is not practically leaked from between the sliding surfaces of the second piston 17B and the second cylinder 15B. A seal portion that includes the outer O-ring groove 27, the outer O-ring 28, the inner O-ring groove 29, and the inner O-ring 30 is configured to keep the inside of the second cylinder 15B airtight. A plurality of O-rings may be provided on the outer peripheral surface and the inner peripheral surface of the second piston 17B. It is good also as a seal part comprised including an O ring and a cap seal.
[0030]
Returning to FIG. 1A again, the description will be continued. The second lower wall 33B between the lower surface 31 of the chuck base 11 and the second lower surface 32B of the second cylinder 15B has four (may be five or more) second through holes 34B. Four second piston rods 35B (the same number as the second through holes 34B) that are processed and connect the holding plate 12 and the second piston 17B through the second through holes 34B are arranged. Yes.
[0031]
A second communication path 20B that communicates between the second cylinder 15B and the second chamber 16B is processed, and a second orifice 21B as a second throttle is formed at a substantially middle position of the second communication path 20B. Is provided.
[0032]
A second fluid supply path 22B (partially shown, partially indicated by a straight line, partially omitted) communicating with the second chamber 16B is processed, and a pressure gauge PI is connected to the middle of the second fluid supply path 22B. Has been. A second gate valve (not shown) is provided at the tip of the second fluid supply path 22B, and a second fluid supply port (not shown) is provided at the tip. In the present embodiment, the same fluid is used as the first fluid and the second fluid. Hereinafter, the first fluid and the second fluid are referred to as fluids. During polishing, the second gate valve is closed, and fluid inflow / outflow does not occur.
[0033]
A pressure signal corresponding to the pressure PhA of the first chamber 16A from the pressure indicating transmitter PIT is sent to the pressure regulator PC. The pressure controller PC compares the pressure PhA based on the pressure signal with a predetermined pressure at which polishing is most appropriately performed. If the pressure PhA is smaller, the pressure controller PC outputs a signal for lowering the chuck base 11 (direction of the polishing surface). Then, it is sent to a chuck base lifting operation device (not shown). The chuck table raising / lowering operation device lowers the chuck table 11. Therefore, the pressure PhA increases to a predetermined value.
[0034]
When the pressure PhA is larger, a signal for raising the chuck table 11 (in a direction away from the polishing surface) is sent to the chuck table lifting operation device. The chuck table raising / lowering operation device raises the chuck table 11. Therefore, the pressure PhA is decreased to a predetermined value.
[0035]
Next, the operation of the embodiment of the present invention will be described.
First, before starting the apparatus, the pressure PhA in the first chamber 16A and the pressure PhB in the second chamber 16B are read by the pressure indicating transmitter PIT (for pressure PhA) and the pressure gauge PI (for pressure PhB). At this time, since the surface is not surfaced, the first and second pistons 17A and 17B are pushed to the lowest point position by the internal pressure of the first and second cylinders 15A and 15B.
[0036]
When these pressures PhA and PhB are lower than a predetermined pressure due to the disappearance of fluid during the previous processing, the first gate valve (not shown), the second gate valve (not shown) are set so that these pressures PhA and PhB become the predetermined pressure. The gate valve is opened, pressure fluid (first fluid, second fluid) is introduced into the first fluid supply passage 22A and the second fluid supply passage 22B, and the pressures PhA and PhB are corrected, and then the first The gate valve and the second gate valve are tightened so that the pressure fluid is sealed. When the pressures PhA and PhB are higher than the predetermined pressure, the first gate valve and the second gate valve are opened, the pressure fluid is discharged so as to reach the predetermined pressure, and the pressures PhA and PhB are corrected.
[0037]
The above is a case where pressure correction is necessary for both the first chamber 16A and the second chamber 16B, and pressure correction for only one of them may be performed. In the case of the first chamber 16A, for example, if the flat plate 13 is a wafer, the predetermined pressure is about 100 to 500 g / cm.² In the case of the second chamber 16B, for example, if the flat plate 13 is a wafer, the surface pressure of the retainer 14 is about 100 to 500 g / cm.² The pressure should be such that
[0038]
Next, in order to mirror-finish the flat plate 13, it is placed on the chuck base 11 by a vacuum suction method. Then, the chuck base 11 and the surface plate 24 are respectively rotated, the chuck base 11 is lowered toward the surface plate 24 at a predetermined feed speed, and the flat plate 13 is pressed against the polishing surface 23. At this time, the polishing surface 23 and the flat plate 13 or the polishing surface 23 and the retainer 14 collide, but the collided flat plate 13 or retainer 14 is connected to the first piston 17A, the second piston 17A, and the second piston 14A. Each piston 17B is pushed up.
[0039]
When the first piston 17A and the second piston 17B are pushed up, the pressure PyA of the first cylinder 15A and the pressure PyB of the second cylinder 15B increase. Therefore, a differential pressure between the pressure PhA in the first chamber and the pressure PhB in the second chamber is generated, and the fluid flows from the first piston 17A and the second piston 17B to the first cylinder 15A and the second cylinder 15B, respectively. Flowing.
[0040]
Therefore, the pressure PyA and the pressure PyB are decreased, the pressure PhA and the pressure PhB are increased, and the first fluid and the second fluid are the first fluid until the pressure PyA is equal to the pressure PhA and the pressure PyB is equal to the pressure PhB. It flows through the orifice 21A and the second orifice 21B. Therefore, the increase in pressure PyA and pressure PyB due to the collision is alleviated.
[0041]
Even during the polishing, the flat plate 13 and the retainer 14 are displaced due to the waviness and uneven wear of the polishing surface 23, that is, the first piston 17A and the second piston 17B are displaced, and the first piston 17A and the second piston 17B are displaced. The displacement of the piston 17B causes the pressure PyA and the pressure PyB to fluctuate, causing the fluid to pass through the first orifice 21A and the second orifice 21B, as described above, the damper effect, and the first cylinder 15A and the first cylinder 15A. The displacement of the first piston 17A and the second piston 17B is suppressed by the spring effect due to the repulsive force caused by the compression of the fluid in the second cylinder 15B.
[0042]
Further, in the case of a sudden pressure change such as when the flat plate 13 and the retainer 14 collide with the polishing surface 23 as described above, the first orifice 21A and the second orifice 21B pass. As the fluid velocity increases, the orifice damper effect increases. Therefore, since the resistance force as a damper acting in the direction opposite to the displacement direction of the first piston 17A and the second piston 17B increases, the positional relationship between the flat plate 13 and the retainer 14 changes rapidly and the flat plate 13 Prevents the polishing surface 23 from being strongly pressed. Therefore, it is possible to prevent the flat plate 13 and the surface plate 24 from being damaged and to prevent the life of the polishing surface 23 from being reduced.
[0043]
Moreover, the vibration during polishing accompanying the rotation of the chuck base 11 and the surface plate 24 of the first and second pistons 17A and 17B is attenuated by the damper effect, and the pressures PhA, PhB, PyA, and PyB during polishing continue to fluctuate. It is prevented. For example, even when resonance occurs in the first piston 17A and the second piston 17B due to rotation, the amplitude can be suppressed low.
[0044]
Consider a case in which the polishing surface 23 first collides with one side of the retainer 14 and then collides with the flat plate 13 during chamfering. In this case, first, the second piston 17B is pushed, and then the first piston 17A is pushed. Even when only the second piston 17B is pushed, the second piston 17B is not compressed by the spring effect due to the compression of the fluid in the second cylinder 15B and the damper effect due to the fluid passing through the second orifice 21B. Move smoothly. When the second piston 17B moves to some extent, the flat plate then collides with the polishing surface and the first piston 17A is also pushed at the same time, but the spring effect due to the compression of the fluid in the first cylinder 15A and the first The first piston 17A moves smoothly due to the damper effect caused by the fluid passing through the orifice 21A. Since both pistons are smoothly displaced, the positional relationship between the retainer 14 and the surface of the flat plate 13 is maintained.
[0045]
For example, the above-described damper effect can also be applied to relatively gentle vibrations of the planar plate 13 and the retainer 14 (vibrations of the first piston 17A and the second piston 17B) due to the waviness of the polishing surface 23. It acts to suppress and dampen this vibration. In this case, since the displacement is small, the amount of fluid passing through the first orifice 21A and the second orifice 21B is not so large, so that the damper effect also acts but the first cylinder 15A and the second cylinder 15B Spring effect by air compression is stronger. When the air in the first cylinder 15A and the second cylinder 15B is compressed by the movement of the first piston 17A and the second piston 17B, the first cylinder 15A and the second cylinder 15B are caused by the repulsive force due to the compression. The pressure of the cylinder 15B works to return to the original, and the first piston 17A and the second piston 17B act to return to their original positions. As a result, the pressures in the first cylinder 15A and the second cylinder 15B The difference is maintained.
[0046]
During polishing, if the pressure in the first chamber 16A exceeds a predetermined value for some reason, the pressure signal is sent to the pressure regulator PC by the pressure indication transmitter PIT, and the pressure regulator PC raises the chuck table. Since the first piston is moved in the direction of the polishing surface, the pressure in the first cylinder 15A is reduced, and the first piston 15A is reduced accordingly. The pressure in the chamber 16A decreases to a predetermined value.
[0047]
During polishing, if the pressure in the first chamber 16A falls below a predetermined value for some reason, the pressure signal is sent to the pressure regulator PC by the pressure indication transmitter PIT, and the pressure regulator PC moves down the chuck table. The signal to be sent is sent to the chuck base lifting operation device. Therefore, the first piston 17A moves up with respect to the chuck base 11 and compresses the cylinder 15A, so that the pressure in the first cylinder 15A increases, and the pressure in the first chamber 16A increases accordingly. And a predetermined value.
[0048]
When the lowering speed of the chuck base 11 is lowered to prevent impact at the time of chamfering, the time required for lowering increases, the number of processing units per unit time of the apparatus decreases significantly, and the running cost increases. Since the chuck base 11 of this embodiment can prevent an impact without reducing the descending speed, it is possible to avoid a decrease in the number of processed sheets per unit time.
[0049]
The chuck base 11 of the present embodiment pressurizes and seals the first fluid and the second fluid in the first and second cylinders 15A and 15B and the first and second chambers 16A and 16B, respectively. Compared to a chuck base that is supplied during polishing and controls the polishing pressure, the pressure in the path is less likely to become unstable due to the path closing due to contamination of an abnormal object in the fluid supply path and the reliability is high.
[0050]
The chuck base 11 according to the present embodiment has first and second pistons 17A and 17B, first and second cylinders 15A and 15B, first and second orifices 21A, B, the first and second chambers 16A and 16B are included, and the structure is relatively simple. Therefore, in maintenance and replacement work, the number of workers is not limited, and work time can be reduced. Further, since the number of parts is small and the assembling accuracy is higher, polishing reproducibility is increased.
[0051]
As shown in FIGS. 2A and 2B, the first cylinder 15A and the second cylinder 15B of the flat plate polishing apparatus according to the embodiment of the present invention are supplied with liquid (for example, water, oil) in the first cylinder 15A. When the piston 17A and the second piston 17B are at the lowest point, the first orifice 21A and the second orifice 21B may be filled so as to be immersed. In this case, when the first piston 17A and the second piston 17B are raised and lowered, the liquid passes through the first orifice 21A and the second orifice 21B. Vibration absorption of the flat plate 13 and the retainer 14 during polishing can be performed more smoothly.
[0052]
As shown in FIG. 3, as another embodiment of the chuck base, a plane plate 43, a holding plate 42, a first cylinder 45A / first piston 47A, and a first chamber 46A are arranged in the vertical lower direction in this order. The first cylinder 45A and the first chamber 46A may be filled with a liquid. Also in this case, the first orifice 51A is immersed in the liquid. A gas chamber 55 may be provided above the first chamber 46A. Similarly, the retainer, the second cylinder / second piston, and the second chamber may be arranged in the vertical direction downward in this order to be filled with liquid. Similarly, a gas chamber may be provided above the second chamber.
[0053]
【The invention's effect】
As described above, according to the present invention, since the first cylinder, the first diaphragm, and the first chamber are provided, the positional relationship between the retainer and the flat plate to be polished can be easily maintained. Furthermore, when starting polishing, the impact when the flat plate collides with the polishing surface can be reduced, and vibration of the flat plate during polishing can be suppressed.
[Brief description of the drawings]
FIG. 1A is a schematic cross-sectional view of a flat plate polishing apparatus according to an embodiment of the present invention. FIG. 2B is an enlarged schematic partial cross-sectional view around the first piston. (C) is the expanded typical fragmentary sectional view of the 2nd piston periphery.
FIG. 2A is a schematic partial cross-sectional view of a chuck base when the first cylinder of FIG. 1 is filled with liquid. (B) is a typical fragmentary sectional view of the chuck | zipper stand at the time of filling the 2nd cylinder of FIG. 1 with the liquid.
FIG. 3 is a schematic partial cross-sectional view showing a plane plate, a first cylinder, and a first chamber around a chuck base according to another embodiment.
[Explanation of symbols]
1 Flat plate polishing equipment
11 Chuck stand
12 Holding plate
13 Flat plate
14 Retainer
15A first cylinder
15B 2nd cylinder
16A first chamber
16B Second chamber
17A First piston
17B 2nd piston
20A First communication path
20B Second communication path
21A First orifice
21B Second orifice
22A First fluid supply path
22B Second fluid supply path
23 Polished surface
24 Surface plate
25 O-ring groove
26 O-ring
27 Outer O-ring groove
28 Outer O-ring
29 Inner O-ring groove
30 Inner O-ring
31 Bottom
32A first lower surface
32B second lower surface
33A First lower wall
33B Second lower wall
34A First through hole
34B second through hole
35A first piston rod
35B 2nd piston rod
36 Chuck surface
42 Holding plate
43 flat plate
45A first cylinder
46A First chamber
47A First piston
51A First orifice
55 Air chamber
PhA, PhB, PyA, PyB pressure
PC pressure regulator
PIT pressure indicating transmitter
PI pressure gauge

Claims (7)

A chuck portion having a chuck surface for chucking a flat plate;
A first cylinder forming a closed and chamber a first piston slidable connected to the chuck portion therein,
A piston rod that penetrates a through hole formed in the lower surface of the first cylinder and connects the chuck portion and the first piston;
A first chamber forming a communication chamber with the first cylinder;
A first communication path that communicates the first cylinder and the first chamber, and that has a first throttle in the middle;
A flat plate configured to store a first fluid in an interior of the first cylinder surrounded by the first cylinder and the first piston and in the first chamber. Chuck stand. The first fluid, flat plate chuck table according to claim 1, characterized in that it is enclosed pressurized in the inner and the first chamber of the first cylinder. The first fluid comprises a liquid;
3. The flat plate chuck base according to claim 1, wherein the liquid is filled in the first cylinder and further filled so as to reach at least the first throttle. 4. Pressure measuring means for measuring the pressure of the first fluid;
The flat plate chuck table according to any one of claims 1 to 3 , further comprising pressure adjusting means for adjusting the pressure to be a predetermined value based on the measured pressure. A retainer disposed around a flat plate held by the chuck portion;
A second cylinder having therein a second piston connected to the retainer;
A second chamber communicating with the second cylinder through a second restriction,
The interior of the second cylinder surrounded by the second cylinder and the second piston and the interior of the second chamber are configured to store the second fluid. The flat plate chuck base according to claim 4 . A flat plate chuck base according to any one of claims 1 to 5 ,
A flat plate polishing apparatus comprising a surface plate having a polishing surface for polishing a flat plate. A flat plate polishing method in which a flat plate chucked on the flat plate chuck table according to any one of claims 1 to 5 is rotated and polished by a surface plate having a polishing surface.
Absorbing the impact between the flat plate and the polished surface during chamfering with the flat plate chuck base,
A flat plate polishing method comprising polishing a flat plate with a polishing surface while absorbing vibrations of the flat plate accompanying rotation by the flat plate chuck base.

Images