JP2004039978A - Substrate holding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce linear factors with respect to an airflow path for sucking a substrate. <P>SOLUTION: A substrate holding device A has such an arrangement that grooves 11 are formed in a plane 10 of an suction pad 1 for mounting the substrate B, and that the substrate B is sucked with the suction of air through the grooves 11. The grooves 11 are constituted of an endless groove 11b and a plurality of ended curved grooves 11a, with one end of each of which being coupled to the endless groove 11b and radially formed therefrom. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate holding device that holds a substrate by suction in a semiconductor manufacturing process or the like.
[0002]
[Prior art]
In a manufacturing process of a semiconductor or an electronic component, various substrates such as a glass substrate, a silicon wafer, and a printed board are transported and rotated in each process. As an apparatus for holding a substrate during such transfer, rotation, and the like of the substrate, a substrate holding apparatus that suctions and holds the substrate by vacuum has been proposed.
[0003]
Generally, such a substrate holding device is provided with a groove on a mounting surface of a substrate, and sucks air from the groove to adsorb the substrate to the mounting surface. Further, as the shape of the groove, a groove in which a linear groove is formed radially (for example, JP-A-7-142343) or a groove in which a plurality of concentric grooves are formed (for example, JP-A-5-21584) ). The groove communicates with an exhaust hole opened on the back side of the mounting surface, and the air in the groove is exhausted from the back side of the mounting surface through the exhaust hole by a vacuum pump or the like, and the inside of the groove is evacuated. To the state.
[0004]
[Problems to be solved by the invention]
However, when a linear groove is employed, the flow velocity of air flowing through the groove tends to be higher, and the portion of the substrate on the groove is more likely to be cooled than other portions, and particularly at the start of suction (at the start of suction). At the time of) or at the end of suction (at the time of opening), since air flows in the groove at a stretch, a part of the substrate located on the groove is locally cooled.
[0005]
As described above, when the substrate is locally cooled and a difference occurs in the temperature distribution on the substrate, for example, in a process of applying a resist liquid or a coating liquid on the substrate, the viscosity of the coating liquid on the substrate becomes uneven. And there is a problem that a uniform film cannot be obtained.
[0006]
On the other hand, when the concentric grooves are used, the resistance to the air flowing through the grooves is greater than when the linear grooves are used, so that the flow velocity is not so high. At a glance, the above problem can be solved. However, when a concentric groove is used, the back surface of the mounting surface communicates with the above-described exhaust hole and traverses the concentric groove in the radial direction in order to uniformly exhaust air from the groove. It is necessary to provide a straight linear exhaust groove.
[0007]
This linear exhaust groove also tends to increase the flow velocity of the air flowing through the groove, and especially at the start of suction and at the end of suction, air flows through the exhaust groove at a stretch, so that it is also located above the exhaust groove. Part of the substrate is locally cooled. As a result, a difference occurs in the temperature distribution on the substrate.
[0008]
Therefore, an object of the present invention is to further reduce linear elements in a flow path of air for adsorbing a substrate.
[0009]
[Means for Solving the Problems]
According to the present invention,
In a substrate holding device that forms a groove on a mounting surface of a mounting member on which a substrate is mounted and sucks air from the groove to suck the substrate onto the mounting surface,
Said groove,
With endless grooves,
One end is connected to the endless groove, and a plurality of end-shaped curved grooves formed radially from the endless groove;
And a substrate holding device characterized by having:
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a schematic configuration diagram of a substrate holding device A according to an embodiment of the present invention. The substrate holding device A has a function of rotating a substrate to be held. For example, the substrate holding device A is used in a semiconductor or liquid crystal manufacturing process, supplies a coating solution such as a resist solution onto the substrate, and applies This is a so-called spin coater that uniformly forms a liquid film of the coating liquid on the top. In the present embodiment, this type of substrate holding apparatus will be described as an example. However, it is needless to say that the present invention can be applied to, for example, holding of a substrate in transporting the substrate.
[0011]
In FIG. 1, the suction pad 1 is a mounting member having a mounting surface 10 on which a substrate B is mounted. Grooves 11a and 11b are formed on the mounting surface 10 of the suction pad 1, and these grooves 11a and 11b communicate with a recess 11d provided on the back surface 12 of the suction pad 1 through a hole 11c. I have. The substrate B is held by vacuum suction by sucking air from the grooves 11a and 11b. Details of the suction pad 1 will be described later.
[0012]
A circular flat reinforcing plate 2 is fixed to the back surface 12 of the suction pad 1 in a sealed state with respect to the back surface 12 of the suction pad 1. The reinforcing plate 2 has a hole 2 a at the center thereof, and is fixed to the upper end of the spindle 4 via a flange 3. The flange 3 is also provided with a hole 3a at the center thereof and communicates with the hole 2a.
[0013]
The lower end of the spindle 4 is connected to the motor 5 and rotates by the rotation of the motor 5. Due to the rotation of the spindle 4, the suction pad 1, the substrate B held by the suction pad 1, and the reinforcing plate 2 rotate integrally.
[0014]
The spindle 4 is rotatably supported by upper and lower bearings 5a provided on the inner periphery of a cylindrical support member 5 surrounding the spindle. In addition, a seal portion 5b is provided between the support member 5 and the spindle 4, and an annular space 5c defined by the inner peripheral surface of the support member 5 and the outer peripheral surface of the spindle 4 is substantially airtight. ing.
[0015]
The support member 5 is provided with a hole 5d penetrating from the outer peripheral surface to the space 5c, and the vacuum pump 6 is connected to the hole 5d. On the other hand, the spindle 4 is formed with a hole 4a drilled in the axial direction from the upper end toward the middle portion, and the hole 4a is bent laterally at the lower end thereof and communicates with the space 5c. .
[0016]
Therefore, when the vacuum pump 6 is operated, the air in the grooves 11a and 11b is sucked by the vacuum pump 6 through the holes 5d, the spaces 5c, the holes 4a, 3a and 2a, and the concave portions 11d and the holes 11c of the suction pad 1, and The grooves 11a and 11b are in a vacuum state, and the substrate B is sucked.
[0017]
The substrate holding device A having such a configuration holds the substrate B by suctioning the air in the grooves 11 a and 11 b by the vacuum pump 6, and rotates the substrate B by rotating the spindle 4 by the motor 5. When a coating liquid is dropped from the nozzle 7 onto the substrate B, the coating liquid flows on the substrate B by centrifugal force, and a coating film is formed.
[0018]
Next, the configuration of the suction pad 1, particularly, the grooves 11a and 11b will be described. FIG. 2 is a plan view of the suction pad 1, and FIG. 3 is a cross-sectional view of the suction pad 1 and the reinforcing plate 2 along a line XX in FIG.
[0019]
The suction pad 1 is made of, for example, a resin material such as MC nylon, and is formed in a circular plate shape in the present embodiment, and has a diameter of, for example, 300 to 400 mm and a thickness of about 10 mm. Grooves 11a and 11b are provided on the mounting surface (front surface) of the suction pad 1. The grooves 11a and 11b preferably have, for example, a width and a depth of about 1 mm, respectively.
[0020]
The groove 11b is formed at the center of the suction pad 1, and is configured as an endless groove by forming a circular groove. In the present embodiment, the groove 11b is circular. However, for example, an endless groove having another shape such as an elliptical shape may be employed.
[0021]
On the other hand, the groove 11a is configured as an end-shaped curved groove, one end of which is connected to the groove 11b so that air flows therethrough, and the other end of which is directed toward the periphery of the suction pad 1. It is formed radially. In the present embodiment, each of the grooves 11a has the same shape and a curved shape with a predetermined radius of curvature, and each groove 11a is bent in the same direction around the center of the suction pad 1 to form a spiral. Thus, the flatness of the mounting surface 10 of the suction pad 1 is maintained and the substrate B can be suctioned in a manner similar to the conventional case in which the groove is formed as a plurality of concentric circles. However, the shape of the groove 11a is not limited to an arc shape, other non-linear shapes can be adopted, and the shape of each groove 11a may be different.
[0022]
Although it is possible to form the groove only by the groove 11a by removing the groove 11b, when the groove 11a is formed in a spiral shape as in the present embodiment, the grooves 11a are densely formed at the center thereof. , Its processing is not easy. For this reason, in the present embodiment, the groove 11b is provided at the center, and each groove 11a is connected to this.
[0023]
Next, the concave portion 11d is formed in the center of the back surface 12 of the suction pad 1, and in the case of the present embodiment, is hollowed out into a circle slightly larger than the groove 11b. The hole 11c penetrates from the groove 11b to the concave portion 11d and opens to the back surface 12. The diameter of the hole 11c is preferably, for example, about 1 mm. The hole 11c forms a flow path for air sucked by the vacuum pump 6 from the grooves 11a and 11b.
[0024]
In the case of the present embodiment, the hole 11c communicates only with the groove 11b. This is because, since the groove 11a is connected to the groove 11b, air can be sucked from the groove 11a via the groove 11b without directly connecting the hole 11c to the groove 11a. That is, in the present embodiment, it is sufficient that the hole 11c communicates only with the groove 11b in order to suck air from the groove 11a. In the case of the present embodiment, the holes 11c are arranged at the respective connecting portions of the grooves 11a and 11b in order to more efficiently suck air from the grooves 11a. Not limited to
[0025]
In the suction pad 1 having such a configuration, since the grooves 11a and 11b are configured as described above, since there is no linear element as the suction groove, it is possible to suppress an increase in the flow velocity of the air flowing through the groove. It is possible to prevent a part of the substrate B from being locally cooled.
[0026]
In addition, by connecting the groove 11a to the groove 11b, air can flow between them. Accordingly, it is not necessary to provide a flow path (exhaust path) for sucking air from the grooves 11a and 11b, such as the hole 11c and the concave section 11c, over the entire suction pad 1, and if it is provided corresponding to the groove 11b. Is enough. Therefore, it is possible to design the area of the exhaust path to be smaller, and it is possible to eliminate linear elements at all, or at least reduce the linear elements more than before. For this reason, it is possible to suppress an increase in the flow velocity of the air caused by the shape of the exhaust path as well as the shape of the suction groove, and also to prevent a part of the substrate B from being locally cooled.
[0027]
<Other embodiments>
In the above embodiment, the groove 11b is a single circle. However, the groove 11b may be a plurality of concentric circles, and the groove 11a may be connected to the outermost groove. 4 to 6 show this example, FIG. 4 is a plan view of the suction pad 101, FIG. 5 is a bottom view of the suction pad 101, and FIG. 6 is a suction pad 101 along the line YY in FIG. FIG.
[0028]
The suction pad 101 is different from the suction pad 1 in that the groove 111b is concentric and the shape of the recess 111d is the same, but the other configuration is the same as the suction pad 1 and the mounting surface ( 110), a back surface (112), a spiral groove (111a), and a hole (111c).
[0029]
Three circular grooves 111b are provided at the center of the suction pad 101, and have different diameters concentrically. The groove 111a is connected only to the outermost groove 111b. By making the groove at the center part concentric, the suction force at the center part can be improved, and the flatness of the mounting surface 110 can be improved.
[0030]
In the case of the present embodiment, as shown in FIG. 5, the concave portion 111d provided on the back surface 112 of the suction pad 101 allows air to flow through each groove 111b through the hole 111c. The straight portion does not need to extend over the entire suction pad 101 as compared with the case where only concentric circles are used as suction grooves, and the length thereof can be reduced. . Therefore, it is possible to greatly reduce the number of linear elements as the exhaust path as compared with the conventional substrate holding device.
[0031]
【The invention's effect】
As described above, according to the present invention, the number of linear elements in the air flow path for adsorbing the substrate can be further reduced.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a substrate holding device A according to an embodiment of the present invention.
FIG. 2 is a plan view of the suction pad 1. FIG.
3 is a cross-sectional view of the suction pad 1 and the reinforcing plate 2 along a line XX in FIG.
4 is a plan view of the suction pad 101. FIG.
5 is a bottom view of the suction pad 101. FIG.
6 is a cross-sectional view of the suction pad 101 and the reinforcing plate 2 along a line YY in FIG.

Claims (5)

In a substrate holding device that forms a groove on a mounting surface of a mounting member on which a substrate is mounted and sucks air from the groove to suck the substrate onto the mounting surface,
Said groove,
With endless grooves,
One end is connected to the endless groove, and a plurality of end-shaped curved grooves formed radially from the endless groove;
A substrate holding device comprising: The substrate holding device according to claim 1, wherein the endless groove is a circular groove. A plurality of the circular grooves are provided concentrically,
The substrate holding device according to claim 2, wherein the one end of the curved groove is connected to the outermost circular groove. The substrate holding device according to claim 1, wherein the plurality of curved grooves are formed in a spiral shape. The placing member has a placing surface and a back surface thereof,
A hole forming an air flow path for sucking air from the groove, the hole having an opening on the back surface of the mounting member and communicating only with the endless groove. 2. The substrate holding device according to 1.

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