JP2000183125A - Substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the abrasions of fixed and driven pulleys and a belt, by reducing the frictional forces generated between the fixed and driven pulleys and the belt. SOLUTION: A belt mechanism 60 has a fixed pulley 62 fixed by bolts 61 to the upper end of a holding cylinder, a driven pulley 64 freely turnable around a pulley shaft 63 stood along a rotational axis C2 near the end of a base plate 52, and a belt 65 hung in a spanning way to the fixed and driven pulleys 62, 64. The surfaces of the fixed and driven pulleys 62, 64 are coated with a low- friction material having a lower friction coefficient than their surfaces. In the coating processings of the low-friction material, after forming electroless nickel- plated films on the surfaces of the fixed and driven pulleys 62, 64, the films are impregnated with a fluorinated resin to achieve the coating processings.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus for performing processing on various substrates to be processed such as a semiconductor wafer, a glass substrate for a liquid crystal display device, and a glass substrate for a PDP (plasma display panel).

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process, a substrate processing apparatus for performing various processes on a semiconductor wafer or a square glass substrate is used. The substrate processing apparatus is usually provided with an apparatus for transporting a substrate to be processed in a predetermined direction. As an apparatus for transporting the substrate, for example, a bending / stretching type transfer robot including a lower arm rotatable along a horizontal plane and an upper arm rotatable along a vertical plane at the tip of the lower arm Can be exemplified.

In this bending and stretching type transfer robot, the lower arm is rotated from the contracted state in which the lower arm and the upper arm are vertically overlapped, and the upper arm is rotated in the direction opposite to the rotation direction of the lower arm. The lower arm and the upper arm can be displaced to the expanded state by being rotated by twice the angle of the lower arm. A holding portion for holding a substrate to be transported at a plurality of locations on the peripheral edge of the back surface is provided on the top surface of the tip of the upper arm. Thus, the substrate can be transported in a predetermined direction by bending the upper arm and the lower arm while holding the substrate on the holding portion of the upper arm.

In this transfer robot, a belt mechanism including a pulley and a belt is sometimes used as a transmission mechanism for transmitting a driving force from a driving source to the upper arm. FIG. 5 shows a conceptual configuration of a belt mechanism for transmitting a driving force to the upper arm. The belt mechanism is provided with a driving pulley 1 to which a driving force from a driving source is input, a driven pulley 3 having a base end portion of an arm 2 fixed on an upper surface, and a driving pulley 1 and a driven pulley 3. A belt 4 is provided. The driving pulley 1 and the driven pulley 3
The belt 4 is constituted by a so-called timing belt, which is constituted by a toothed pulley having a large number of teeth formed on its peripheral surface. Therefore, when the driving pulley 1 is rotated by an angle corresponding to the transport distance of the substrate, the rotation of the driving pulley 1 is transmitted to the driven pulley 3 via the belt 4, and the driven pulley 3 is turned to the rotation angle of the driving pulley 1. Rotate by the corresponding angle. Thereby, the substrate held by the arm 2 is transported to a desired position with high accuracy.

[0005]

However, in the above-mentioned belt mechanism, the teeth of the driving pulley 1 and the driven pulley 3 or the teeth of the belt 4 wear as the substrate is transported repeatedly, and the driving pulley 1 and the driven pulley In some cases, the belt 4 wound around the belt 3 became loose. If the belt 4 becomes slack, the rotation angle of the driving pulley 1 is not reliably transmitted to the driven pulley 3, and there is a possibility that the transfer accuracy of the substrate by the arm 2 may vary. Therefore, in the substrate processing apparatus including the belt mechanism, it is necessary to periodically adjust the tension of the belt 4 or replace the belt 4 with a new one.

Further, there is a possibility that abrasion powder of the teeth of the driving pulley 1 and the driven pulley 3 and the teeth of the belt 4 may adhere to the substrate as particles and contaminate the substrate. Therefore,
An object of the present invention is to provide a substrate processing apparatus in which abrasion of a pulley and a belt is suppressed.

[0007]

According to a first aspect of the present invention, there is provided a moving member which moves to perform processing on a substrate, and a driving force from a driving source is applied to the moving member. A substrate processing apparatus comprising: a pulley rotatably provided; and a driving force transmission mechanism having a belt wound around the pulley, wherein the surface of the pulley is in contact with the belt or the surface of the belt is At least one of the surfaces contacting the pulley is coated with a low-friction material having a friction coefficient lower than the friction coefficient of the surface itself.

[0008] The pulley is preferably constituted by a toothed pulley having a large number of teeth formed on a peripheral surface thereof, and the belt is a timing belt having a large number of teeth formed on a surface in contact with the peripheral surface of the pulley. It is preferred to be composed of According to this configuration, at least one of the surface of the pulley that contacts the belt and the surface of the belt that contacts the pulley is coated with a low-friction material having a friction coefficient lower than the friction coefficient of the surface itself. The frictional force generated between the pulley and the belt is reduced, and the wear of the pulley and the belt can be suppressed.

[0009] This makes it possible to prevent the belt from being loosened due to the wear of the pulley and the belt, so that the frequency of the tension adjustment for maintaining the belt tension at a constant tension can be reduced. Further, the life of the pulley and the belt can be extended. Furthermore, since the wear of the pulley and the belt is suppressed, the amount of particles generated by the wear is reduced, and the possibility that the substrate is contaminated by the particles can be reduced.

According to a second aspect of the present invention, the moving member includes:
The substrate processing apparatus according to claim 1, further comprising a substrate holding member for holding the substrate. This claim 2
As described in, when the moving member can move while holding the substrate with the substrate holding member, it is possible to prevent the belt from being loosened due to the wear of the pulley or the belt, so that the substrate by the moving member can be prevented. Can maintain good transfer accuracy. Further, when a substrate is transferred to or from another substrate holding unit (for example, a spin chuck), the substrate holding member can be accurately moved to a position where the substrate holding unit is provided. The transfer of the substrate between the substrate holding member and another substrate holding means can be favorably performed.

The invention according to claim 3 is the substrate processing apparatus according to claim 1 or 2, wherein the low friction material contains a fluororesin. According to this configuration, since the low friction material contains the fluorine resin, the friction coefficient of the pulley or belt coated with the low friction material is reduced, and the heat resistance and the chemical liquid resistance are improved. Therefore, when the substrate processing apparatus performs processing on the substrate using a chemical solution such as hydrofluoric acid, even if the chemical solution adheres to the pulley or the belt, the chemical solution component may corrode the pulley or the belt. Absent.

[0012]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a plan view conceptually showing a partial configuration of a substrate processing apparatus according to an embodiment of the present invention. This substrate processing apparatus is for removing unnecessary substances such as particles, abrasives, and extra thin films attached to the surface of a semiconductor wafer W (hereinafter, simply referred to as “wafer W”). A chemical treatment section MTC and a washing / drying treatment section DTC are provided. A transfer robot STR for transferring the wafer W from the chemical processing section MTC to the washing / drying processing section DTC is provided between the chemical processing section MTC and the washing / drying processing section DTC.

The wafer W to be processed is first carried into the chemical processing section MTC. The chemical processing section MTC includes a spin chuck 11 that rotates while horizontally holding the wafer W, and a chemical nozzle (FIG. 1) for supplying a chemical such as hydrofluoric acid to the surface of the wafer W held by the spin chuck 11. (Not shown). The wafer W carried into the chemical processing section MTC is subjected to a cleaning process using a chemical by being supplied with a chemical from a chemical nozzle while being rotated by the spin chuck 11.

The wafer W that has been processed by the chemical processing section MTC is washed and dried by the transfer robot STR.
Transferred to TC. A spin chuck 21 that rotates while holding the wafer W horizontally is provided in the washing / drying processing unit DTC.
And a pure water nozzle (not shown) for supplying pure water to the surface of the wafer W held by the spin chuck 21. The rinsing / drying processing unit DTC supplies pure water from a pure water nozzle to the surface of the wafer W held by the spin chuck 21 to remove a chemical solution attached to the surface of the wafer W. Thereafter, the spin chuck 21 is rotated at a high speed, and the moisture adhering to the wafer W is shaken off by centrifugal force to be dried.

FIG. 2 is a sectional view showing the structure of the transfer robot STR. The transfer robot STR includes a lower arm 31 that is rotated around a rotation axis C1 along the vertical direction, and a rotation axis C along the vertical direction at the tip of the lower arm 31.
Upper arm 3 provided so as to be rotatable around 2
2 is provided. The upper arm 32 includes a plurality of hand members 3 having an arc-shaped guide surface along the periphery of the wafer W.
3 and a plurality of hand members 3 are provided in a state where the guide surface of the hand member 33 is in contact with the end surface of the wafer W.
3 has a structure capable of holding the wafer W.

The lower arm 31 is rotated by transmitting the rotation of a rotation shaft 34 disposed along the rotation axis C1. To the lower end of the rotating shaft 34, the rotating force from the motor M is transmitted by the pulleys 35 and 36 and the timing belt 37. In order to detect the rotation state of the motor M, the motor M is provided with an encoder EN.

When the motor M is energized, the rotating shaft 34 rotates, and accordingly, the lower arm 31 rotates around the rotating axis C1. At this time, the upper arm 32 is
Due to the function of a belt mechanism (to be described later) incorporated in the lower arm 31, the lower arm 31 rotates in a direction opposite to the rotation direction by twice the rotation angle of the lower arm 31. Therefore, by rotating the lower arm 31 approximately 90 degrees counterclockwise about the rotation axis C1 from the standby state shown by the solid line in FIG. 1, the upper arm 32 is treated with the chemical solution as shown by the two-dot chain line in FIG. Section MTC. By rotating the lower arm 31 approximately 90 degrees clockwise about the rotation axis C1 from the standby state shown by the solid line in FIG. 1, the upper arm 32 is washed and dried as shown by the two-dot chain line in FIG. It can enter into the processing unit DTC. That is, the lower arm 31 and the upper arm 32 bend and stretch between a standby state shown by a solid line in FIG. 1 and a developed state shown by a two-dot chain line in FIG. 1 to move the wafer W from the chemical processing section MTC. It can be transferred to the washing / drying processing section DTC.

The transfer robot STR is provided between the upper arm 32 and the spin chuck 11 of the chemical processing section MTC and the spin chuck 21 of the washing / drying processing section DTC.
The lower arm 31 and the upper arm 32 are movable up and down so that the wafer W can be transferred. Specifically, the holding cylinder 38 surrounding the rotating shaft 34 is attached to an attachment member 41, and the attachment member 41 includes:
A pair of guide blocks 43 that slide on guide rails 42 arranged along the vertical direction are fixed. The lower end of the mounting member 41 is connected to a rod 44a of the air cylinder 44. Therefore, by moving the rod 44a of the air cylinder 44 forward and backward, the holding cylinder 38 can be moved up and down, and the lower arm 31 and the upper arm 32 can be moved up and down.

FIG. 3 is a sectional view showing the internal configuration of the lower arm 31. FIG. 4 is a plan view showing the internal configuration of the lower arm 31 in a simplified manner. The lower arm 31 is provided rotatably with respect to a holding cylinder 38 surrounding the rotating shaft 34, and a base plate 52 attached to an upper end of the holding cylinder 38 via a bearing 51, It has a peripheral plate 53 rising from the peripheral edge and a top plate 54 provided so as to close the upper end of the peripheral plate 53. FIG. 4 shows a state where the top plate 54 is removed.

The top plate 54 is fixed by bolts 56 to a connecting member 55 for connecting the rotating shaft 34 and the top plate 54. The connecting member 55 is connected to the base plate 52.
Are fixed with bolts 57 to the base end. Therefore,
The rotation of the rotating shaft 34 is performed by connecting the base plate 5
2 and the top plate 54, whereby the lower arm 3
1 rotates around the holding cylinder 38 (rotation axis C1).

A belt mechanism 60 as a driving force transmitting mechanism for rotating the upper arm 32 in conjunction with the rotation of the lower arm 31 is provided inside the lower arm 31. The belt mechanism 60 includes a fixed pulley 62 fixed to the upper end of the holding cylinder 38 by bolts 61 and a driven pulley rotatable around a pulley shaft 63 erected along the rotation axis C2 near the tip of the base plate 52. 64, and a belt 65 wrapped around the fixed pulley 62 and the driven pulley 64.
The fixed pulley 62 and the driven pulley 64 are constituted by toothed pulleys having a large number of teeth formed on the peripheral surface thereof, and a belt 65
Is constituted by a timing belt having a large number of teeth formed on a surface in contact with the fixed pulley 62 and the driven pulley 64.

The driven pulley 64 is integrally formed with a cylindrical mounting portion 66 protruding upward. The mounting portion 66 projects above the top plate 54 via a hole 58 formed near the tip of the top plate 54. A base end portion 32 a of the upper arm 32 is fixed to an upper surface of the attachment portion 66 with a bolt 59. Accordingly, the upper arm 32 can be rotated around the rotation axis C2 at the tip of the lower arm 31 with the rotation of the driven pulley 64.

With the above configuration, when the lower arm 31 rotates clockwise in FIG. 4 about the rotation axis C1, the pulley shaft 63 of the driven pulley 64 erected on the base plate 52 moves around the fixed pulley 62. Revolves clockwise in the figure. At this time, since the fixed pulley 62 is fixed to the holding cylinder 38 and does not rotate, the driven pulley 64 is revolved by the revolution of the pulley shaft 63 with respect to the fixed pulley 62 while the teeth formed on the peripheral surface thereof mesh with the teeth of the belt 65. 4 rotates counterclockwise in FIG. 4 around the pulley shaft 63. As a result, the upper arm 32 attached to the driven pulley 64 rotates counterclockwise in FIG. 4 around the rotation axis C2. Conversely, when the lower arm 31 rotates counterclockwise in FIG. 4 about the rotation axis C1, the driven pulley 64 revolves clockwise in FIG. 4 around the pulley shaft 63, and the upper arm 32 rotates. It rotates clockwise in the figure around the axis C2.

Therefore, if the number of teeth of the driven pulley 64 is set to の of the number of teeth of the fixed pulley 62, the upper arm 32
To the lower arm 3 in the direction opposite to the rotation direction of the lower arm 31.
It can be rotated by twice the rotation angle of 1. As described above, since the fixed pulley 62 and the driven pulley 64 are constituted by toothed pulleys, and the belt 65 is constituted by a timing belt, the teeth of the fixed pulley 62 and the driven pulley 63 and the teeth of the belt 65 are used with use. , And the belt 65 may be loosened. When the belt 65 is loosened, the upper arm 32 is not accurately rotated by twice the rotation angle of the lower arm, and the upper arm 32 is rotated by the spin chuck 21 (see FIG. 1) of the washing / drying processing unit DTC or the chemical processing unit. There is a possibility that the MTC may not be accurately moved to the position of the spin chuck 11 (see FIG. 1).

Therefore, in the substrate processing apparatus according to this embodiment, at least the surfaces of the fixed pulley 62 and the driven pulley 64 are formed of a metal material (iron, stainless steel, copper, aluminum, or an alloy thereof). The surfaces of the pulley 62 and the driven pulley 64 are coated with a low-friction material having a friction coefficient lower than that of the surfaces. The coating process of the low-friction material on the fixed pulley 62 and the driven pulley 64 is performed by, for example, the fixed pulley 62 and the driven pulley 64.
This is achieved by forming an electroless nickel plating film (porous film) on the surface of the substrate and impregnating the film with a fluororesin.

As a result, the frictional force generated between the fixed pulley 62 and the driven pulley and the belt 65 is reduced,
Teeth and belt 65 of fixed pulley 62 and driven pulley 64
Of the belt 65 due to such wear of the teeth can be prevented. Therefore, the upper arm 32 can be accurately positioned below the spin chuck 11 (see FIG. 1) of the chemical processing section MTC, so that the hand member 33 of the upper arm 32 can successfully hold the substrate. Further, since the upper arm 32 can be accurately positioned above the spin chuck 21 (see FIG. 1) of the washing / drying processing unit DTC, the wafer W held by the upper arm 32 can be
Good transfer to the spin chuck 21 (see FIG. 1) of the washing / drying processing unit DTC is possible.

Since the wear of the fixed pulley 62, the driven pulley 64 and the belt 65 is suppressed, the fixed pulley 6
2. The service life of the driven pulley 64 and the belt 65 can be extended. Further, since the abrasion of the fixed pulley 62, the driven pulley, and the belt 65 is suppressed, the amount of particles generated by the abrasion is reduced, so that the risk of contamination of the substrate by the particles can be reduced.

In addition, since the low friction material contains a fluorine resin, the friction coefficient of the fixed pulley 62 and the driven pulley 64 is reduced, and the heat resistance and the chemical resistance are improved. Therefore, even if the atmosphere containing the chemical enters the lower arm 31, there is no possibility that the fixed pulley 62 and the driven pulley 64 are corroded by the chemical.

Further, the substrate processing apparatus according to the present embodiment has a configuration in which even if the belt 65 is loosened,
A tension adjusting mechanism 70 is provided so that the tension of the belt 65 can be easily adjusted. The tension adjusting mechanism 70 has tension rollers 71, 72 rotatably provided around shafts 71a, 72a along the vertical direction, and an interlocking mechanism 73 for moving the tension rollers 71, 72 in an interlocking manner. I have.

The interlocking mechanism 73 has a rotary plate 75 erected at a peripheral position where the shafts 71a and 72a face each other. The rotary plate 75 is formed in a circular recess 74 formed near the center of the base plate 52. It is fitted. The rotating plate 75 includes the rotating shaft 3
4 (rotation axis C1) and the pulley shaft 63 (rotation axis C2) are attached to the base plate 52 by a bolt shaft 76 provided on a straight line. The bolt shaft 76 is provided around the bolt axis 76 in a plane along the base plate 52. It is rotatable. The rotating plate 75 has an arc-shaped elongated hole 7 centered on the bolt shaft 76.
7, 78 are formed. Fixing bolts 79a and 79b are inserted into the elongated holes 77 and 78, respectively, and the rotation of the rotating plate 75 with respect to the base plate 52 can be restricted by fastening the fixing bolts 79a and 79b.

The tension rollers 71 and 72 are
5 is arranged symmetrically with respect to the bolt shaft 76 on the upper surface of the driven pulley 6 regardless of the rotational position of the rotary plate 75.
4 can be brought into contact with the outer peripheral surfaces of the belts 65 located on both sides. In an initial state immediately after assembling the belt mechanism 60, the shaft 71a of the tension roller 71 and the shaft 72a of the tension roller 72 are included in a plane orthogonal to a straight line connecting the rotation axis C1 and the rotation axis C2 in plan view. ing.

When the rotating plate 75 is rotated, the two tension rollers 71 and 72 rotate in association with each other by the same amount of rotation, and the two tension rollers 71 and 72 move in a direction intersecting the belt 65, and The path length of the belt 65 between the driven pulley 64 and the driven pulley 64 is increased,
The tension of 5 increases. Therefore, when adjusting the tension of the belt 65, the fixing bolts 79a and 79b are loosened and the rotating plate 75 is rotated, and the fixing bolts 79a and 79b are tightened with the belt 65 at a predetermined tension. It is only necessary to adjust the positions of the two tension rollers 71 and 72 individually. Therefore, the tension of the belt 65 can be easily adjusted.

As described above, according to this embodiment, since the surfaces of the fixed pulley 62 and the driven pulley 64 are coated with a low friction material, the wear of the fixed pulley 62, the driven pulley 64 and the belt 65 is suppressed. Is done.
Thus, the belt 65 can be prevented from being loosened due to the wear, so that the transfer accuracy of the wafer W by the upper arm 32 can be kept good. Further, since the slack of the belt 65 is prevented, it is not necessary to frequently adjust the tension of the belt 65, and the labor for adjusting the tension can be reduced.

Further, since the tension adjusting mechanism 70 is provided, even if the belt 65 becomes loose, the tension of the belt 65 can be easily adjusted only by rotating the rotating plate 75. . Therefore, even if it becomes necessary to adjust the tension of the belt 65, no trouble is required for the adjustment work. Although the description of one embodiment of the present invention is as described above, the present invention is not limited to the above embodiment. For example, in the above embodiment, the coating process of the low-friction material on the fixed pulley and the driven pulley is performed by forming an electroless nickel plating film (porous film) on the metal surface of the fixed pulley and the driven pulley, and forming a fluorine film on the film. It is said to be achieved by impregnating the resin. However, the coating process of the low-friction material on the fixed pulley and the driven pulley may be performed, for example, when the surfaces of the fixed pulley and the driven pulley are formed of aluminum. And impregnating with a fluororesin.

Further, in the above embodiment, the surfaces of the fixed pulley and the driven pulley are coated with a low-friction material, but the surface of the belt that contacts the fixed pulley and the driven pulley is coated with the low-friction material. May be done. For example, the contact surface of the belt is coated with a fluororesin or the like. Further, the surfaces of the fixed pulley and the driven pulley and the surface of the belt may be coated with a low friction material. For example, the surfaces of the fixed pulley and the driven pulley are coated with the above-described electroless nickel plating and impregnated with a fluororesin, and the surface of the belt is coated with a fluororesin. In this case, the wear of the pulley and the belt can be further suppressed as compared with the case where one of the surfaces of the pulley and the belt is coated with a low friction material.

Further, in the above embodiment, the case where the present invention is applied to a bending and stretching type transfer robot has been described as an example. However, the present invention has a driving force transmission mechanism including a pulley and a belt, for example. It can also be applied to spin chucks and the like. Further, the present invention is not limited to a substrate processing apparatus for processing a wafer, but may be applied to an apparatus for processing another type of substrate such as a glass substrate for a liquid crystal display device or a glass substrate for a PDP. The same can be applied.

In addition, various design changes can be made within the scope of the technical matters described in the claims.

[Brief description of the drawings]

FIG. 1 is a plan view conceptually showing a partial configuration of a substrate processing apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a configuration of a transfer robot.

FIG. 3 is a sectional view showing an internal configuration of a lower arm.

FIG. 4 is a plan view showing a configuration of a belt mechanism built in a lower arm.

FIG. 5 is a diagram showing a conceptual configuration of a driving force transmission mechanism using a belt.

[Explanation of symbols]

 32 upper arm (moving member) 33 hand member (substrate holding member) 60 belt mechanism (driving force transmission mechanism) 62 fixed pulley 64 driven pulley 65 belt

Claims (3)

[Claims] A moving member for moving the substrate, a pulley rotatably provided to apply a driving force from a driving source to the moving member, and a belt wound around the pulley. A driving force transmitting mechanism having a driving force transmission mechanism, wherein at least one of a surface of the pulley that contacts the belt or a surface of the belt that contacts the pulley,
A substrate processing apparatus, wherein the substrate processing apparatus is coated with a low-friction material having a friction coefficient lower than a friction coefficient of the surface itself. 2. The substrate processing apparatus according to claim 1, wherein said moving member includes a substrate holding member for holding a substrate. 3. The substrate processing apparatus according to claim 1, wherein the low friction material contains a fluorine resin.