JP2000286185A - Spin chuck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate accurate alignment of rotary direction between a spin chuck and a substrate, when carrying and fitting a substrate in a configuration where the spin chuck for retaining the substrate and rotating it for performing treatment onto the surface is supported only at the peripheral part of the reverse side of the substrate, to prevent a main part inside the reverse side from being contaminated, scratched, or the like. SOLUTION: A substrate-support member 59 that is provided on the upper surface of a bottom plate 57 is arranged, so that the main part on the lower surface of a substrate is lifted from the bottom plate 57 by supporting the lower surface peripheral edge part of a substrate W, a vacuum suction hole is provided on it for suction and friction force for preventing sliding, when accelerating or decelerating the rotation operation of a spin chuck, is obtained, and the need for the positional regulation of a regulation pin in a rotating direction for regulating the horizontal position of the substrate W to be placed is eliminated. Then the regulation pin is arranged on the same circle according to the diameter of the substrate W to be applied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spin chuck, and more particularly to a spin chuck which rotates to chuck one surface of a substrate and perform processing on the other surface. The present invention relates to a spin chuck in which a main part is not stained or scratched.

[0002]

2. Description of the Related Art Conventionally, a spin chuck which holds a substrate and rotates to perform processing such as application of a chemical solution on the surface of the substrate is configured to hold the back surface of the substrate by vacuum suction. However, due to the strong suction force, chuck marks are left on the back surface of the substrate, and the chuck marks add to the contamination from the previous process, causing a shift in the height of the substrate surface, for example, a focus error during photoresist exposure. There was a problem that caused. In addition, when particles attached to the back surface of the substrate separate and are accommodated in a cassette, they contaminate the surface of the substrate accommodated on the lower side, or transfer to the substrate transport device and contaminate other substrates. There was such a problem. Furthermore, in the case where the substrate is a semiconductor wafer and the back surface is processed by rotating with a spin chuck, there is a problem that the semiconductor devices are built on the front side, but these are rejected.

In order to avoid the above-mentioned problem, there is a proposal in Japanese Patent Application Laid-Open No. Hei 8-222512.

[0004] The spin chuck will be described with reference to the drawings. 4 is a plan view of a main part, and FIG. 5 is a perspective view of the main part.
FIG. 6 is an enlarged sectional view of an essential part. A spin chuck 3 that mounts and holds an outer peripheral edge of the substrate W on an upper end of a rotating shaft (not shown) that rotates around a vertical axis by driving an electric servomotor (not shown) can be integrally rotated. Attached to. The spin chuck 3 is provided with six regulating pins 8... At predetermined intervals in the circumferential direction on a bottom plate 7 connected to a rotating shaft (not shown) so as to be integrally rotatable. Three pin-shaped substrate support members 9 for supporting the substrate W are provided on the rotation center side, and the restricting pins 8 are brought into point contact with the outer peripheral edge of the substrate W to adjust the horizontal position of the substrate W. In addition to the restriction, the substrate W is configured to be brought into point contact with the back surface of the substrate W to support the substrate W. Two of the restricting members 8...
Are provided so that the rotational force can be effectively transmitted to the substrate W by making point contact with the outer peripheral edge of the orientation flat.

As shown in an enlarged sectional view of a main portion of FIG. 6, a cylindrical body 11 extending downward at three predetermined locations on the downward surface of the bottom plate 7 is provided.
A lower portion of the substrate support member 9 is fitted in the cylindrical body 11 so as to be able to move up and down, and a compression coil spring 12 for urging the substrate support member 9 to be displaced downward is provided. ing. An opening 13 is formed at a lower portion of the cylindrical body 11, and a pressing member 14 that is brought into contact with the substrate supporting member 9 and rises corresponding to a position below the opening 13.
Are provided so as to be able to move up and down, and an air cylinder 15 is connected to the pressing member 14 in an interlocking manner. The structure including the pressing member 14 and the air cylinder 15 is referred to as elevating means.

With the above structure, when the substrate W is loaded, the pressing member 14 is pressed against the spin chuck 3 stopped at a predetermined rotation angle position by a rotary encoder or the like.
Is raised, and is brought into contact with the substrate supporting member 9 to be raised to the transfer position of the substrate W. After the transfer of the substrate W, the pressing member 14 is lowered to the outside of the cylindrical body 11 to
The substrate supporting member 9 is brought into a non-contact state, the substrate supporting member 9 is lowered by the elastic restoring force of the compression coil spring 12, and the substrate W is lowered to the processing position. In this state, the substrate W is rotated to apply a resist solution, for example. Then
When the substrate W is carried out, the rotation of the spin chuck 3 is stopped at a predetermined rotation angle position by a rotary encoder or the like, the pressing member 14 is raised with respect to the spin chuck 3, and the substrate W comes into contact with the substrate support member 9 and is supported thereon. The transported substrate W is lifted to the transfer position and carried out.

[0007]

The spin chuck 3
According to the above description, the horizontal position is regulated by the regulating pins 8..., And the substrate W is supported by three pin-shaped substrate supporting members disposed on the rotation center side (peripheral portion of the substrate W) with respect to the regulating pins 8. Since the support is provided from the lower surface, the main portion (the middle portion) of the lower surface of the substrate W is not stained or damaged. However, since the spin chuck 3 does not perform vacuum suction, regulating pins 8 are provided so as to regulate the position of the orientation flat OF as shown in FIG. The substrate W does not slip even when the rotation is accelerated or decelerated. Therefore, in order to place the substrate W thereon, the rotational position of the spin chuck 3 and the rotational position of the substrate W must be accurately aligned. Therefore, while accurately stopping at a predetermined rotation angle position using a rotary encoder, etc.,
The device for transporting the substrate W also needs a function of accurately controlling the direction of the substrate W. That is, an apparatus using the spin chuck 3, for example, a photoresist coating apparatus requires a high degree of control of a stop angle position, and is not suitable for a simple and inexpensive apparatus, for example, a simple apparatus for attaching and detaching a substrate by hand. It is. Therefore, in the present invention, similar to the above-mentioned spin chuck, the main part at the center of the lower surface of the substrate does not become dirty or damaged, and the rotational direction position of the substrate and the rotational direction position of the spin chuck at the time of mounting the substrate are different. Provided is a spin chuck that does not require highly accurate alignment.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a rotatable bottom plate integrally attached to the upper end of a rotating shaft, and a plurality of standing plates arranged on the upper surface thereof at predetermined intervals in a circumferential direction. A regulating pin that regulates the horizontal position of the mounted substrate, and a substrate supporting member that is provided on the upper surface of the bottom plate, supports the lower peripheral edge of the mounted substrate, and floats a main portion of the lower surface of the substrate from the bottom plate. A vacuum chuck hole provided at a portion of the substrate support member for supporting the substrate. According to the above configuration, the main portion of the lower surface of the substrate is supported from the bottom plate by supporting the peripheral portion of the lower surface, so that the main portion of the lower surface of the substrate on the center side is not stained or damaged. Since a vacuum suction hole is provided in a portion of the substrate support member that supports the substrate, if the vacuum suction hole is suctioned, a frictional force for transmitting the rotation operation of the spin chuck to the substrate can be obtained. Therefore, it is not necessary for the regulation pins for regulating the horizontal position of the substrate to regulate the rotational position of the substrate.

Therefore, it is preferable that the restriction pins are arranged on the same circle according to the diameter of the substrate to be applied. This eliminates the necessity of performing high-accuracy alignment of the spin chuck and the substrate in the rotation direction when transporting and mounting the substrate having the orientation flat.

The substrate supporting member is structured to support with a small contact area, has a vacuum suction hole opened on the top surface, and is arranged at a plurality of positions in the circumferential direction at positions supporting the outer peripheral portion of the substrate. Alternatively, the substrate may have an annular shape that supports the outer peripheral portion of the substrate, and the supporting surface may have vacuum suction holes arranged at a plurality of positions in the circumferential direction.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings. FIG. 1 is a plan view of a main part of an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA, and FIG. 3 is a cross-sectional view taken along line BB in FIG. A spin chuck 53 that mounts and holds an outer peripheral edge of the substrate W is integrally rotatably attached to an upper end of a rotating shaft 51 that rotates around a vertical axis by driving of an electric servomotor (not shown). I have. The spin chuck 53 is provided with six regulating pins 8... At predetermined intervals in a circumferential direction on a bottom plate 57 connected to the rotating shaft 51 so as to be integrally rotatable, and is slightly closer to the rotation center than the regulating pins 8. Are provided at six locations for supporting the substrate W with a small contact area, and the restricting pins 8 are brought into point contact with the outer peripheral edge of the substrate W to regulate the horizontal position of the substrate W. , The substrate support members 59 are point-contacted to the back surface of the substrate W to support the substrate W so that the lower surface of the substrate W does not contact the bottom plate 57. Control member 8
Are arranged on the same circle regardless of the orientation flat of the substrate W.

The substrate support members 59 have a vacuum suction hole 59a opened on the top surface thereof to form a vacuum suction nozzle. The vacuum suction holes 59a are connected to an intake pump (not shown) via bottom plates 57 and ventilation paths 57a and 51a provided in the rotating shaft 51.

With the above structure, when the substrate W is carried in, the regulating pins 8 are arranged on the same circle even if the spin chuck 53 is not accurately stopped at a predetermined rotation angle position. Can be loaded and installed without accurately adjusting the direction of the camera. In other words, the orientation flat part happens to be positioned and the vacuum suction hole 5
The accuracy may be sufficient to avoid a situation where 9a is not blocked and cannot be absorbed. Then, the substrate W is fixed on the substrate supporting members 59 by vacuum suction through the vacuum suction holes 59a. The attraction force is considerably weaker than the attraction force utilizing the entire lower surface of the substrate, but it is sufficient that the friction to the extent that no slip occurs when the spin chuck 53 is accelerated or decelerated is obtained. The regulation of the substrate in the horizontal direction is performed by the regulation pins 8.

In this state, the substrate W is rotated to apply a resist solution, for example. Next, when the substrate W is carried out, the rotation of the spin chuck 53 is stopped, vacuum suction is cut off, and the substrate W is taken out.

According to the spin chuck 53, since the substrate supporting members 59 are provided so as to support the outer peripheral portion of the substrate W, the main portion is not scratched or contaminated in the lower surface of the substrate W. Then, the substrate support members 59 ...
Is used as a vacuum suction nozzle, so that the rotation of the spin chuck 53 can be accelerated and decelerated so that the substrate W does not slip when it is decelerated, so that it is not necessary to arrange the regulating pins in alignment with the orientation flat. well,
In this case, there is an advantage that positioning is not required with high precision when carrying and mounting the substrate.

In the above embodiment, the substrate supporting members 59 are configured to support the outer peripheral portion of the substrate W in a point-like manner (with a small contact area). At this time, a plurality of vacuum suction holes may be provided so as to perform suction.

[0017]

As described above, according to the spin chuck of the present invention, the outer peripheral portion of the substrate is supported, the main portion of the lower surface of the substrate is lifted to prevent the generation of dirt and scratches, and the supporting portion is vacuum-adsorbed. Therefore, a frictional force can be obtained to transmit the rotational movement of the spin chuck to the substrate, and it is not necessary to regulate the position of the substrate in the rotational direction with the regulating pin.

Therefore, when the regulating pins are arranged on the same circle, it is not necessary to perform high-precision positioning in the rotating direction when the substrate is transported and mounted, thereby simplifying the apparatus.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line AA.

FIG. 3 is a sectional view taken along line BB in FIG. 1;

FIG. 4 is a plan view of a main part of a conventional spin chuck.

FIG. 5 is a perspective view thereof.

FIG. 6 is a sectional view of a main part thereof.

[Explanation of symbols]

 8 Regulatory Pin 51 Rotating Shaft 53 Spin Chuck 57 Bottom Plate 59 Substrate Supporting Member 59a Vacuum Suction Hole W Substrate

Claims (4)

[Claims] A rotatable bottom plate integrally attached to an upper end of a rotating shaft; and a plurality of standing plates provided on a top surface of the bottom plate at predetermined intervals in a circumferential direction to regulate a horizontal position of a substrate to be placed. A pin, a substrate supporting member provided on the upper surface of the bottom plate, supporting a lower peripheral edge of the substrate to be placed, and allowing a main portion of the lower surface of the substrate to float from the bottom plate; and a portion of the substrate supporting member supporting the substrate. A spin chuck comprising a vacuum suction hole. 2. The spin chuck according to claim 1, wherein said regulating pins are arranged on the same circle in accordance with the diameter of a substrate to be applied. 3. The substrate supporting member has a structure in which it is supported with a small contact area, and has a vacuum suction hole opened on the top surface thereof, and is disposed at a plurality of positions in the circumferential direction at positions supporting the outer peripheral portion of the substrate. The spin chuck according to claim 1 or 2, wherein 4. The apparatus according to claim 1, wherein said substrate support member has an annular shape for supporting an outer peripheral portion of the substrate, and has a plurality of vacuum suction holes arranged at a plurality of positions in a circumferential direction on a support surface thereof. Or the spin chuck according to claim 2.