JPH11170162A - Surface polishing surface plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form a plurality of cooling passages having an equal passage length by concentrically forming a plurality of coolant passing circumferential grooves differed in size whose circumferences are partially discontinued around the center of a surface plate, and mutually connecting the inner and outer circumferential grooves by a proper number by communicating holes. SOLUTION: A plurality of coolant passing circumferential grooves 11-16 differed in size whose circumferences are partially discontinued are formed on the upper surface of a base concentrically around the central axial line L of a surface plate 1 at equal intervals, and a plurality of circumferential grooves situated on the inner and outer sides are mutually connected in series by communicating holes 17, 18, whereby a plurality of cooling passages 4, 5, 6 having an equal passage length are formed. Since a refrigerant is carried from the outer side of the surface plate 1 to the inner side in each cooling passage 4, 5, 6, the outer circumferential side can be locally cooled with high efficiency even if the temperature tends to become higher on the outer circumferential side according to the polishing of a work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface plate for polishing a surface of a work such as a semiconductor wafer or a magnetic disk substrate.

[0002]

2. Description of the Related Art In a planar polishing apparatus such as a lapping apparatus or a polishing apparatus, when a work is pressed against a rotating platen and polished, heat is generated at an interface between the platen and the work due to friction between the platen and the work. In addition, there is a problem that the surface plate is thermally deformed by the heat and the polishing accuracy is reduced. Therefore, a cooling chamber is formed inside the surface plate, and cooling water is allowed to flow through the cooling room to cool the surface plate.
Since the flow of the cooling water is disturbed by the rotation of the surface plate, or the heated cooling water easily stays on the outer peripheral side of the surface plate, uniform cooling is hardly performed, and a sufficient effect has not been obtained.

In order to solve such a problem, for example, Japanese Unexamined Patent Publication No. Hei 6-39704 discloses a method in which two spiral refrigerant flow paths having the same flow path length are formed inside a surface plate. Disclosed is a configuration in which a refrigerant flows from the inside to the outside of the surface plate in the path, and the refrigerant flows from the outside to the inside of the surface plate in the other flow path.

According to the improved platen, since the refrigerant can be almost uniformly flowed through the entire platen by the two refrigerant passages having the same flow path length, the cooling effect is also excellent. It is a very difficult processing technique to form a spiral groove on the board, and a more difficult processing technique is required if a plurality of grooves are continuously and uniformly formed from the inside to the outside of the platen.

Further, the entire surface plate does not always generate heat evenly during processing, and the heat generation temperature varies locally due to the surface shape of the surface plate which changes due to wear, the difference in sliding contact between the inner and outer circumferences with the work, and the like. In many cases, particularly, the temperature on the outer peripheral side of the platen tends to increase. Therefore, in order to make the temperature uniform over the entire surface plate, local fine temperature adjustment is necessary.However, the conventional surface plate described in the above publication has a spiral refrigerant flow path formed by the surface plate. Since the refrigerant is formed continuously from the inner peripheral end to the outer peripheral end and the refrigerant flows in the two refrigerant flow paths in the opposite directions from the inside and the outside, it is not possible to locally finely adjust the temperature of the surface plate. Have difficulty.

[0006]

The main technical problem of the present invention is that a plurality of cooling channels having the same channel length can be simply formed by a plurality of circumferential grooves without forming a spiral groove. An object of the present invention is to provide a surface plate that can be easily processed and manufactured and has an excellent cooling effect.

Another technical object of the present invention is to make it possible to perform local fine adjustment of temperature on the above-mentioned surface plate.

[0008]

In order to solve the above-mentioned problems, a surface plate according to the present invention comprises a plurality of circumferential grooves, each part of which is discontinuous, for circulation of refrigerant having different sizes. , And a plurality of cooling channels having the same channel length are formed by connecting a suitable number of inner and outer circumferential grooves to each other through communication holes.

According to the present invention, a plurality of concentric circumferential grooves are connected to each other by an appropriate number,
A plurality of cooling channels having the same channel length can be formed. For this reason, the surface plate is easier to process and manufacture than a conventional product in which a plurality of spiral grooves are continuously formed from the inner peripheral end to the outer peripheral end of the surface plate. In addition, since the plurality of cooling channels allow the refrigerant to flow evenly over the entire surface plate,
Superior cooling effect.

In one embodiment of the present invention, an even number of the circumferential grooves are formed at regular intervals, and the circumferential grooves located at the same order counted from the outer peripheral side and the inner peripheral side of the platen are connected to each other. ing.

In a preferred specific embodiment of the present invention, the discontinuous portions of the mutually connected inner and outer circumferential grooves of the respective cooling passages are located at the same position in the radial direction, and the communication holes extend in the radial direction. And the discontinuous portions and the communication holes in the plurality of cooling channels are radially arranged at an equal angle.

In the present invention, the plurality of cooling passages may be connected to a common coolant supply passage or different coolant supply passages.

According to a preferred specific configuration of the present invention, the outer circumferential groove among the inner and outer circumferential grooves connected to each other in each cooling flow path is connected to the refrigerant supply flow path. The refrigerant is configured to flow from the outer peripheral side to the inner peripheral side of the platen. This makes it possible to efficiently cool the outer peripheral side of the surface plate, where the temperature is likely to increase, and to make the entire surface plate a uniform temperature.

In the present invention, it is preferable that the surface plate has at least three cooling channels.

[0015]

1 and 2 show an embodiment of a surface plate according to the present invention. The surface plate 1 comprises a surface plate main body 2 which slides on a work directly or via a pad or the like. It is attached to the upper surface of the base 3.

On the upper surface of the base 3, a plurality of circumferential grooves 11 to 16 of different sizes, each part of which is discontinuous, are formed around the central axis L of the surface plate 1. A plurality of circumferential grooves formed concentrically at equal intervals and located inside and outside are connected to each other in series by communication holes 17, 18, 19, so that a plurality of cooling passages 4, 5 having the same passage length are provided. 6 are formed. More specifically, six first to sixth circumferential grooves 11, 12, 13, 14, 1 having the same cross-sectional area are provided.
5 and 16 are formed in the base 3, and the circumferential grooves located in the same order counted from the outer circumferential side and the inner circumferential side of the surface plate 1, that is, the first circumferential groove 11 positioned on the outermost side and The sixth inner circumferential groove 16 located on the innermost side, and the second circumferential groove 16 located on the innermost side.
A circumferential groove 12 and a fifth circumferential groove 15 located second from the inside,
The third circumferential groove 13 located third from the outside and the fourth circumferential groove 14 located third from the inside are each formed with the communication hole 1.
The three cooling passages 4, 5, and 6 having the same passage length are formed by being connected by 7, 18, and 19.

The two inner and outer circumferential grooves 11 and 16, 12 and 15, 13 and 14 constituting the cooling channels 4, 5 and 6 are
The discontinuous portions 20 are formed so as to be at the same position in the radial direction, and the groove ends 11a and 16a, 12a and 15a, 13a and 14a located on the same left and right sides of the discontinuous portion 20 Are connected to each other by the communication holes 17, 18, and 19, which are formed substantially radially in the inside of the. The discontinuous portions 20 and the communication holes 17, 18, 19 of the respective circumferential grooves in the three cooling passages 4, 5, 6 are 12
They are arranged radially at equal angles of 0 degrees each. The communication holes 17, 18, and 19 are formed from the peripheral side surface of the base 3, and are configured by closing unnecessary portions on the outside with a plug member 25.

In each of the cooling passages 4, 5, and 6, a refrigerant inlet is provided at the other end of each of the first, second, and third circumferential grooves 11, 12, and 13 located outside. 21 are formed, and the sixth circumferential groove 16 and the fifth circumferential groove 1 located on the inside are formed.
5. An outlet 22 for the refrigerant is formed at each end of the fourth circumferential groove 14, and each of the inlets 21 is connected to a common refrigerant supply passage 23 which leads to a supply source of the refrigerant such as water or gas. At the same time, the outlets 22 are connected to the common refrigerant discharge passage 24 so that the cooling passages 4, 5, 6
The refrigerant flows from the outside toward the inside.

The surface plate 1 having the above-described structure is composed of a plurality of circumferential grooves 11, 12, 13, 14, 15, 1 positioned concentrically.
Since a plurality of cooling passages 4, 5, and 6 having the same passage length can be formed only by connecting a suitable number of them to each other,
Processing and manufacturing of the platen are very easy as compared with a conventional product in which a plurality of spiral grooves are continuously formed from the inner peripheral end to the outer peripheral end of the platen.

Further, a plurality of cooling passages 4 having the same passage length,
Since the refrigerant can be uniformly flowed through the entire surface plate by the steps 5 and 6, the cooling effect can be improved. In particular, each cooling channel 4, 5,
6, the temperature of the platen 1 rises as the work is polished, and the temperature of the platen 1 increases toward the outer peripheral side due to a difference in sliding contact with the work. Even if the rise tends to increase, the outer peripheral side can be locally and efficiently cooled. In addition, the coolant in the outermost first circumferential groove 11, which absorbs heat by cooling the surface plate 1 and has the highest temperature, is transferred to the innermost sixth circumferential groove 16, which has the lowest temperature rise. Guiding the refrigerant in the second circumferential groove 12 whose temperature rise is smaller than that of the first circumferential groove 11 to the fifth circumferential groove 15 whose temperature rise is larger than that of the sixth circumferential groove 16,
Third circumferential groove 1 having a lower temperature rise than second circumferential groove 12
By guiding the refrigerant in 3 to the fourth circumferential groove 14 whose temperature rise is larger than that of the fifth circumferential groove 15, the temperature of the entire surface plate can be simply and efficiently uniformized.

In the above embodiment, the cooling channels 4, 5, and 6 are connected to the common refrigerant supply channel 23 so that the same type and the same temperature of the refrigerant are supplied. The two cooling passages may be connected to different refrigerant supply passages to supply different types of refrigerants such as water and gas, or to supply the same or different refrigerants having different temperatures or different flow rates. Can be supplied. By supplying the coolants having different temperatures and different flow rates to the cooling passages 4, 5, and 6, the coolant inlets 21 in the cooling passages 4, 5, and 6 are arranged in the radial direction of the platen 1 in the radial direction. Combined with being provided at different positions, local fine adjustment of the temperature of the platen can be performed more easily and more reliably than when a common refrigerant is supplied.

The number of the cooling channels 4, 5, 6 does not need to be three as in the illustrated embodiment, but may be two or four or more. It is determined by the size of the board and the cross-sectional area of the circumferential groove.

Further, in the illustrated embodiment, in connecting the two inner and outer circumferential grooves in each of the cooling flow paths 4, 5, 6, the groove ends located on the same left and right sides of the discontinuous portion 20 are mutually connected. The connection allows the refrigerant to flow in the inner and outer circumferential grooves in the opposite directions. However, the groove ends located on the left and right opposite sides of the discontinuous portion 20 may be connected to each other, thereby forming the inner and outer circles. The direction of the flow of the refrigerant in the circumferential groove can be made the same.

[0024]

As described above, according to the present invention, a plurality of concentric circumferential grooves are formed and inner and outer circumferential grooves are connected to each other without forming spiral grooves. A plurality of cooling passages having the same diameter can be easily formed, so that the working and manufacturing of the surface plate are easy, and the cooling effect is superior. In addition, by supplying a coolant having a different temperature or flow rate to each cooling channel, the temperature of the platen can be locally finely adjusted.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a surface plate according to the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Surface plate 4,5,6 Cooling flow path 11,12,13,14,15,16 Circumferential groove 17,18,19 Communication hole 20 Discontinuous part 23 Refrigerant supply flow path

Claims (7)

[Claims] 1. A plurality of circumferential grooves, each having a discontinuous part of the circumference, for flowing refrigerant having different sizes are formed concentrically around the center of the platen, and a suitable number of circumferential grooves are formed inside and outside the plate. Characterized in that a plurality of cooling passages having the same passage length are formed by connecting the plurality of cooling passages with each other through communication holes. 2. An even number of circumferential grooves, each part of which has a discontinuous circumference, for refrigerant flow, are formed concentrically at equal intervals around the center of the platen. A plurality of cooling passages having the same passage length are formed by connecting the circumferential grooves located at the same order from the outer peripheral side and the inner peripheral side with communication holes, thereby forming a plurality of cooling passages having the same passage length. Surface plate. 3. The platen according to claim 1, wherein 1
The discontinuous portions of the inner and outer circumferential grooves forming the two cooling passages are located at the same position in the radial direction, are connected to each other by the communication holes extending substantially in the radial direction, and have a plurality of cooling passages. The discontinuous portion and the communication hole are radially arranged at an equal angle. 4. The surface plate according to claim 1, wherein said plurality of cooling channels are connected to a common coolant supply channel. 5. The surface plate according to claim 1, wherein at least one of the plurality of cooling channels is connected to a coolant supply channel different from the others. thing. 6. The surface plate according to claim 4, wherein an outer one of the inner and outer circumferential grooves connected to each other in each cooling flow path is connected to the refrigerant supply flow path. Thus, the refrigerant is configured to flow from the outer peripheral side to the inner peripheral side of the surface plate. 7. The platen according to claim 1, wherein the platen has at least three cooling passages.