JPH1145870A - Spin processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spin processor which enables satisfactory retention of a substrate, without causing warpings of a holding table even with rotational driving. SOLUTION: A spin processor 20 has a holding table 30 and a retention means 39 for retaining an outer periphery of a substrate 31 of an upper surface of the holding table 30, and rotationally drives the substrate 31 together with the holding plate 30. In this case, on a lower surface of the holding table 30 opposite to the side where the retention means 39 is provided, a balance weight 41 which generates a reverse force against the force which acts in a direction perpendicular to the holding table 30 generated in the retention means 39 by the rotational driving of the holding table 30 is mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spin processing apparatus for performing a cleaning process and a drying process by rotating a substrate.

[0002]

2. Description of the Related Art For example, in a manufacturing process of a liquid crystal display device, there are a film forming process and a photo process for forming a circuit pattern on a rectangular glass substrate as a work. In these processes, the processing of the substrate and the cleaning are repeatedly performed.

In order to dry the washed substrate, the substrate is held on a holding table, rotated at a high speed together with the holding table, and a centrifugal force generated thereby is used to remove the cleaning liquid attached to the substrate. That is being done.

A holding table for holding the rectangular substrate has a disk-shaped main body, and four arms are provided at predetermined intervals in a circumferential direction on a disk-shaped outer periphery of the main body. It is provided on the outer periphery. The four arms have the same length, and at the tip of each arm are two first pins that are separated at a predetermined interval as engagement portions, and are shorter than the first pins. One second pin protrudes from the first pin located closer to the base end of the arm.

On the upper surface of the holding table, four corners of the substrate are engaged with a pair of first pins of each arm, and lower surfaces of the corners are supported by the second pins. That is, the substrate is held with the four arms of the holding table along the diagonal direction of the rectangle.

When the holding table holding the substrate is rotated at a high speed, the cleaning liquid attached to the substrate is removed by centrifugal force, and the substrate can be dried.

[0007]

Recently, the size of the liquid crystal display device has been increased, and the size of the substrate has been increased. For example, in the past it was 300 mm × 400 mm,
Recently, substrates having a size of 550 mm × 650 mm have been used.

Therefore, when the substrate is placed on the holding table and the substrate is driven to rotate, the centrifugal force for pushing the first pin outward is also large. Here, since the first pins are provided so as to protrude from the upper surface of the holding table, as shown in FIG. 4, the holding table 1 is bent downward by a predetermined dimension d. This is because, when the first pin 2 rotates, a centripetal force F is generated from the center of gravity P of the first pin 2 toward the rotation center O of the holding table 1 so that the first pin 2 can rotate. When the centripetal force F is decomposed into a horizontal component F ₁ and a vertical component F ₂ , the vertical component F ₂ acts as a force to bend the holding table 1 downward.

The warpage of the holding table 1 occurs not only in the case of the holding table constituted by the four arms but also in the case of, for example, a square table. As an example of a square table, when a 900 mm square holding table is driven to rotate at 1600 rpm, the position where the first pin 2 is attached may warp downward by about 7 mm.

When the holding table 1 is warped downward in this manner, the first pins 2 cannot satisfactorily lock the outer edge of the substrate 3 and, therefore, the substrate 3
There is a problem that the substrate 3 is damaged by scattering outward from the substrate.

Further, even when the first pin 2 is temporarily attached to the lower surface of the holding table 1, the holding table 1 is warped to the upper surface by rotation.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a spin processing apparatus which can hold a substrate well without rotating a holding table even by rotational driving. Things.

[0012]

According to the first aspect of the present invention,
In a spin processing apparatus having a holding table and a locking means for locking the outer periphery of the substrate on the upper surface of the holding table, and rotating the substrate together with the holding table, the opposite side where the locking means of the holding table is provided A balance weight for generating a reverse force against a force acting on the holding table in a direction perpendicular to the holding table generated by the rotation means of the holding table due to the rotation of the holding table is attached to a lower surface of the holding table. .

According to a second aspect of the present invention, there is provided the spin processing apparatus according to the first aspect, wherein the balance weight is attached to an outer peripheral side of the locking means. According to the first aspect of the present invention, the lower surface of the holding table opposite to the side on which the locking means is provided is provided with a force generated in the locking means by the rotation driving of the holding table and acting in a direction perpendicular to the holding table. Since a balance weight for generating a reverse force is attached to the holding table, if the holding table is rotationally driven, a downward force generated by the locking means to push down the holding table and a holding table generated by the balance weight are reduced. The upward force pushing up cancels each other out, so that it is possible to prevent the holding table from warping downward.

According to the second aspect of the present invention, since the balance weight is attached to the outer peripheral side of the locking means, the weight of the balance weight can be reduced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The spin processing device 20 shown in FIG. The cup 21 includes a lower cup 21a and an upper cup 21b. The lower cup 21a is formed in a bowl shape with an open upper surface, a through hole 22 is formed at the bottom center portion, and a receiving flange 23 is formed at the upper end edge of the outer periphery.

The upper cup 21b is formed in a ring shape with an outer peripheral surface having a convex curved surface, and a coupling flange 25 is provided on the outer peripheral surface via a mounting member 24.
The upper cup 21b is integrated by joining the connecting flange 25 to the receiving flange 23 via a packing 26 and connecting them with a plurality of wing nuts 27.

A through hole 22 formed in the lower cup 21a
The drive shaft 29 of the motor 28
Is inserted. A holding table 30 is attached to the upper end of the drive shaft 29, and is rotated at a high speed by the motor 28. This holding table 3
At 0, a rectangular substrate 31 used in the liquid crystal display device that has been cleaned in the cleaning process, which is the previous process, is held as described later. Therefore, when the holding table 30 is rotated at a high speed, the cleaning liquid attached to the substrate 31 is removed by centrifugal force.

A plurality of drain ports 32 are provided on the bottom wall of the lower cup 21a, and the drain ports 32 are connected to a drain pump (not shown) by piping. Also, the lower cup 21a
A plurality of exhaust ports 33 are connected to the peripheral wall at predetermined intervals in the circumferential direction above the lower end of the upper cup 21b, and these are connected to an exhaust pump (not shown) by piping.

The washing liquid accumulated in the lower cup 21a is discharged from the drain port 32, and the exhaust port 33 indicates an air flow generated by the high-speed rotation of the holding table 30 as shown by an arrow A in FIG. A suction force for smooth flow is generated.

As shown in FIG. 2, the holding table 30
A central part 34 formed in a disk shape;
Has a main body portion 36 composed of two sets of arms 35a and 35b, each pair of which is provided on the outer periphery at 90 ° intervals, for example. Each of the arms 35a and 35b is provided at the tip of a straight rod portion 37 such that the tip 38 has, for example, a T-shape. Note that the tip portion 38 is not limited to the T-shape, but may be set in various shapes such as a hook shape.

The tip 38 of each of the arms 35a and 35b
A pair of first pins 39 forming an engaging portion are erected at predetermined intervals in the circumferential direction on the upper surface of the
A second pin 40 having a lower height than the first pin 39 is provided upright at a portion radially inward of the first pin 39 and between the pair of first pins 39. I have.

The distance between the first pins 39 provided on the pair of first arms 35a is set slightly larger than the width of the substrate 31 in the short direction, and is provided on the pair of second arms 35b. The distance between the first pins 39 is
1 is set slightly larger than the dimension in the longitudinal direction orthogonal to the lateral direction.

Therefore, the board 31 is engaged on both sides in the width direction with the first pins 39 of the pair of first arms 35a,
A pair of second arms 3 on both sides in the longitudinal direction orthogonal to the width direction.
5b is engaged with the first pin 39, and the lower surface of each side is engaged with and held by the upper end of the second pin 40 provided on the base end side of the first pin 39. It has become.

The first arm 35a and the second arm 3
A balance weight 41 is attached to the lower surface of the position 5b where the first pin 39 is attached.
The balance weight 41 is attached to generate an upward force against the downward force generated on the first pin 39 due to the rotational driving of the holding table 30. Therefore, the weight of the balance weight 41 is And the height is adjusted appropriately.

However, the balance weight 41
The protruding height is appropriately limited in order to prevent the airflow from affecting the surrounding due to the air resistance generated by the rotational drive and the rotation of the balance weight 41.

The position at which the balance weight 41 is attached is not limited to below the first pin 39, but may be radially outer or inner. For example, when the balance weight 41 is attached to the radially outer side, the weight of the balance weight 41 can be reduced.

In the balance weight 41, since the weight and the position of the center of gravity are important factors, the shape is such that the weight and the position of the center of gravity satisfy the required requirements and the air resistance is low (for example, Any shape can be used as long as the shape is a columnar shape, a conical shape, and the like, and the upper end portion has a gentle curved surface.

The operation of the spin processing device 20 configured as described above will be described below. When the motor 28 is operated to rotate the holding table 30, the first pin 3 provided on the holding table 30 is provided.
A centripetal force due to rotation is generated at the center of gravity P of No. 9. FIG. 3 (a)
As shown in the figure, this centripetal force is the center of gravity P of the first pin 39.
From the direction toward the rotation center O of the holding table 30, and this is referred to as a centripetal force F. Disassembling the centripetal force F and vertical component F ₂ horizontal components F _1, the vertical component F ₂ acts in an effort deflect the holding table 30 downward. The vertical component F ₂ is to exacerbate the holding of the substrate 31 by the first pin 39 in an attempt deflect the holding table 30 downward.

However, the balance weight 41 is attached to the lower surface of the holding table 30. Therefore, the balance weight 41 is also driven by the rotation of the holding table 30 so that the center of gravity Q of the balance weight 41 can be adjusted.
, A centripetal force W toward the rotation center O of the holding table 30 is generated. This is shown in FIG.

When the centripetal force W is decomposed into a horizontal component W ₁ and a vertical component W ₂ , the vertical component W ₂ acts to push up the holding table 30 to bend upward.

Therefore, the above-described downward force F ₂ and upward force W ₂ cancel each other, and the bending of the holding table 30 can be prevented. By appropriately adjusting the weight and the mounting position of the balance weight 41, it is naturally possible to completely eliminate the bending generated in the holding table 30.

When the bending of the holding table 30 is prevented as described above, the locking state of the first pins 39 attached to the upper surface of the holding table 30 to the substrate 31 is deteriorated, and therefore, the holding table 30 It is possible to prevent the substrate 31 from jumping out during the rotational driving of the substrate 31.

While the embodiment of the present invention has been described above, the present invention can be variously modified. This is described below. In the above embodiment, the holding table 30 is constituted by the four arms 35a and 35b. However, other than this, various types of holding tables such as a 900 mm square plate-shaped table may be used. Applicable.

[0034]

As described above, according to the first aspect of the present invention, the lower surface of the holding table opposite to the side on which the locking means is provided is generated in the locking means by the rotational driving of the holding table. Since a balance weight for generating a force in the opposite direction to the force acting in the vertical direction is attached to the holding table, if the holding table is rotationally driven, the holding table generated in the locking means is pushed down. The downward force and the upward force generated by the balance weight and pushing up the holding table cancel each other out, so that it is possible to prevent the holding table from warping downward.

According to the second aspect of the present invention, since the balance weight is attached to the outer peripheral side of the locking means, the weight of the balance weight can be reduced.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a shape of a spin processing device according to an embodiment of the present invention.

FIG. 2 is a plan view showing the shape of the holding table according to the embodiment.

3A and 3B are diagrams illustrating a state of a force generated when the holding table according to the embodiment is rotationally driven, FIG. 3A is a diagram illustrating a state of a force generated on a first pin, and FIG. The figure which shows the state of the force which arises in a weight.

FIG. 4 is a diagram showing the bending of a holding table that occurs in a conventional holding table and the force that occurs on the holding table.

[Explanation of symbols]

 Reference Signs List 20 spin processing device 21 cup 30 holding table 31 substrate 35a, 35b arm 39 first pin 41 balance weight

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Kenji Sakashita 1000-1, Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa, Japan Inside Ofuna Plant of Shibaura Works

Claims (2)

[Claims] 1. A spin processing apparatus having a holding table and a locking means for locking an outer periphery of a substrate on an upper surface of the holding table, and rotating the substrate together with the holding table. On the lower surface on the opposite side provided, a balance weight for generating a reverse force against a force acting on the retaining table in a direction perpendicular to the retaining table generated by the rotation drive of the retaining table is attached. A spin processing device characterized by the above-mentioned. 2. The spin processing apparatus according to claim 1, wherein said balance weight is attached to an outer peripheral side of said locking means.