JPH09153476A - Rotary-type substrate drying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary-type substrate drying device which is capable of surely preventing processing liquid droplets attached to a substrate from flying away out of an anti-splash cup. SOLUTION: A rotary-type substrate drying device 3 is equipped with a spin chuck 13 which is rotated by a motor 26 around a rotating shaft directed in a vertical direction as an axis and a nearly cylindrical anti-splash cup 15 which stops processing liquid droplets which fly away from a substrate. The height H of the droplet stop cup 15 above the surface of the substrate W supported by the spin chuck 13 is so set as to enable an elevation angle θ made by a line connected between the center of rotation on the surface of the substrate W and the upside periphery 40 of the anti-splash cup 15 with the surface of the semiconductor substrate W to be equal to 17 deg. or so.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary substrate drying device for drying a substrate by rotating it.

[0002]

2. Description of the Related Art As one of apparatuses for drying substrates such as semiconductor wafers and glass substrates for liquid crystal display panels, a rotary substrate drying apparatus called a spin dryer is used. In this rotary substrate drying device, a supporting means for supporting the substrate in a posture in which the surface is horizontal is rotated at high speed around a vertical axis to shake off and remove the droplets adhering to the substrate. It is configured to receive the droplets scattered from the substrate by a cylindrical scattering prevention cup arranged so as to surround the means.

[0003]

In such a rotary substrate dryer, a part of the liquid droplets scattered from the substrate is scattered over the upper end of the scattering prevention cup,
For example, the substrate transfer device or the like arranged on the side of the rotary substrate drying device may be contaminated.

For this reason, a shutter that can be opened and closed is provided around the rotary substrate drying device, and when the substrate after transportation is dried by rotation, the shutter is closed to prevent contamination by splashed droplets. However, there is a problem that not only an extra processing time for opening and closing the shutter is required but also the apparatus becomes complicated.

The present invention has been made to solve the above problems, and it is an object of the present invention to provide a rotary substrate drying device capable of reliably preventing droplets from a substrate from splashing out of a splash-preventing cup. To aim.

[0006]

According to a first aspect of the present invention, a liquid is attached to a substrate by rotating a supporting means for supporting the substrate in a posture in which the surface thereof is horizontal about a vertical axis. In a rotary substrate drying apparatus, which shakes off the droplets and receives the droplets scattered from the substrate by a cylindrical scattering prevention cup arranged so as to surround the periphery of the supporting means, the height of the scattering prevention cup To
It is characterized in that the height is equal to or higher than the maximum reaching height of the droplet at that position.

According to a second aspect of the present invention, in the first aspect of the invention, the elevation angle from the center of rotation on the surface of the substrate to the upper end portion of the shatterproof cup is 10 degrees or more.

According to a third aspect of the invention, in the invention according to the first or second aspect, the supporting means is rotated at a low speed for a fixed time and then at a high speed.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

First, a substrate processing apparatus to which the rotary substrate drying apparatus according to the present invention is applied will be described. FIG. 1 is a plan view of a substrate processing apparatus to which a rotary substrate drying apparatus according to the present invention is applied.

This substrate processing apparatus performs processing on a rectangular glass substrate for a liquid crystal display panel, and includes a substrate loading section 2, a rotary substrate drying apparatus 3 according to the present invention, and a substrate unloading section 4. And a substrate transfer section 5.

The substrate carry-in section 2 is a substrate W in a state in which a treatment liquid such as pure water has been attached since the treatment process using the treatment liquid in the preceding stage.
For carrying in the rotary substrate drying device 3,
A plurality of transport rollers 12 that transport the substrate W by rotating in synchronization with each other are provided.

As will be described later, the rotary substrate drying device 3 is for drying the substrate W by rotating the substrate W at a high speed, and the spin chuck 13 for holding and rotating the substrate W and the substrate W. A gas supply means 14 for supplying gas to the surface and a cup 15 for preventing scattering of the processing liquid are provided.

The substrate unloading section 4 is for unloading the substrate W which has been dried by the rotary substrate drying device 3 to the subsequent processing step, and like the substrate unloading section 2, rotates in synchronization with each other. Accordingly, the plurality of transport rollers 12 that transport the substrate W are provided.

The substrate carrying section 5 is for carrying the substrate W among the substrate carry-in section 2, the rotary substrate drying device 3 and the substrate carry-out section 4, and the carrying roller 12 of the substrate carry-in section 2.
A first chuck 16 for transporting the substrate W placed on the spin chuck 13 of the rotary substrate dryer 3.
And a second chuck 17 for transporting the substrate W placed on the spin chuck 13 of the rotary substrate drying device 3 onto the transport roller 12 of the substrate unloading unit 4. The first and second chucks 16 and 17 are both connected to a synchronous belt 19 driven by a motor 18, and move in the left-right direction in FIG. 1 in synchronization with each other.

Next, the rotary substrate drying device 3 according to the present invention will be described. FIG. 2 is a side view of the rotary substrate drying device 3, and FIG. 3 is a plan view thereof.

The spin chuck 13 has two crossing points.
Each arm 13 is composed of a book arm 13a, 13b.
Five support pins 2 for supporting the substrate W from below are provided at the tips of the a and 13b and the substantially central portion of the arm 13b.
2 are erected. In addition, eight positioning pins 23 for contacting the edge of the substrate W and positioning the substrate W are provided upright at the tips of the arms 13a and 13b.
Further, at the intersection of the arms 13a and 13b,
An opening 24 is formed on the back surface of the substrate W for supplying nitrogen gas and pure water.

The spin chuck 13 is connected to a rotary shaft 27 of a motor 26 via a connecting tool 25, and the motor 2
By the driving of 6, the substrate W held there is rotated about the axis of rotation 27 that is oriented in the vertical direction. Motor 26
A hollow shaft is used as the rotating shaft 27 of the rotating shaft 27, and a double pipe 28 for supplying nitrogen gas and pure water to the back surface of the substrate W is arranged in the hollow portion of the rotating shaft 27. . The double pipe 28 is connected to a pure water supply pipe 29 and a nitrogen gas supply pipe 32.

The gas supply means 14 is swingable about a shaft 33, and a nozzle 35 supported by the base 34 and connected to a nitrogen gas supply source (not shown) through a conduit 36.
And As shown by the chain double-dashed line in FIG. 2, the nozzle 35 has a shape bent in multiple stages, and its base end is connected to the base portion 34 beyond the upper end 40 of the shatterproof cup 15. Further, the tip of the nozzle 35 has a height close to the surface of the substrate W supported by the spin chuck 13 up to about several mm when it is moved to the nitrogen gas supply position shown by the chain double-dashed line in FIGS. Has become.

The base portion 34 of the gas supply means 14 is connected to an air cylinder 37 arranged outside the scattering prevention cup 15 via a link mechanism. Therefore, the gas supply means 14 is driven by the air cylinder 37 to reciprocate between the standby position shown by the solid line in FIGS. 2 and 3 and the nitrogen gas supply position shown by the chain double-dashed line.

The scattering prevention cup 15 is for preventing scattering of droplets of the processing liquid scattered from the substrate W rotated by the spin chuck 13 to the outside, and has a substantially cylindrical shape that covers the outer periphery of the spin chuck 13. Has the shape of. The height H of the scattering prevention cup 15 with respect to the surface of the substrate W supported by the spin chuck 13 is determined by an elevation angle θ from the rotation center on the surface of the substrate W to the upper end 40 of the scattering prevention cup 15.
Is set to about 17 degrees.

The height H needs to be equal to or higher than the maximum arrival height of the droplets of the processing liquid scattered from the substrate W at the position of the upper end 40 of the scattering prevention cup 15 in plan view. The height H needs to be set to an appropriate value depending on the maximum rotation speed of the spin chuck 13 and the size of the descending air flow to be described later. The elevation angle θ from the rotation center on the surface of W to the upper end 40 of the scattering prevention cup 15 is preferably set to a value that is 10 degrees or more, and more preferably 15 degrees or more. found.
Note that if the height H is excessively increased, it will hinder the transfer of the substrate W by the first and second chucks 16 and 17 and the supply of nitrogen gas by the gas supply means 14. Therefore, the elevation angle is about 45 degrees or less. It is preferable that

At the inner lower part of the scattering prevention cup 15, four waste liquid outlets 38 for discharging the processing liquid scattered from the substrate W are circumferentially equally divided with respect to the rotation shaft 27 of the motor 26. It is arranged. In addition, inside the waste liquid port 38, 4
The individual exhaust ports 39 are arranged substantially equally in the circumferential direction with respect to the rotary shaft 27 of the motor 26. The exhaust port 39 is generated by exhausting the inside of the scattering prevention cup 15 to form a descending airflow in the scattering prevention cup 15, and the processing liquid scattered from the substrate W collides with the scattering prevention cup 15. It is for discharging fine droplets (mist) to the outside of the system together with the descending airflow.

Next, the step of drying the substrate W in the rotary substrate drying device 3 will be described. FIG. 4 is a time chart showing the rotation state of the spin chuck 13.

First, in the substrate loading unit 2, the first chuck 16 holds the substrate W transported by the plurality of transport rollers 12 with the treatment liquid such as deionized water adhered thereto in the previous treatment step. , And is placed on the spin chuck 13 of the rotary substrate drying device 3. At this time, the first chuck 1
6, a processing liquid supply nozzle (not shown) is attached to supply a processing liquid such as deionized water to the substrate W being transferred, and the surface of the substrate W is dried in a non-uniform state when the substrate W is transferred. Prevent uneven processing due to the above.

The substrate W is the support pin 2 of the spin chuck 13.
When the spin chuck 1 is placed on the spin chuck 1 and the positioning by the positioning pin 23 is completed, the spin chuck 1 is driven by the motor 26.
3 is rotated about the rotation shaft 27 at a low rotation speed of about 200 rpm, for example. At this time, in the scattering prevention cup 15, a downward airflow is formed in advance by exhausting air from the exhaust port 39.

It should be noted that the spin chuck 13 is rotated at a low speed first because when the substrate W is rotated at a high speed from the beginning of the rotation, a large amount of the processing liquid adhering to the substrate W is scattered around the liquid. Since the jumping occurs, the processing liquid is intended to flow out from the edge of the substrate W in advance. The rotation speed at this time may be any rotation speed that generates a centrifugal force that allows the processing liquid adhering to the surface of the substrate W to flow out from the edge of the substrate W, and is preferably 500 rpm or less, for example. Further, the time T1 for maintaining this rotation speed may be a time during which most of the processing liquid adhering to the surface of the substrate W can flow out from the edge of the substrate, for example, 1.5 to
About 3 seconds is sufficient.

In this state, pure water is supplied from the pure water supply pipe 29 to the double pipe 28, and this pure water is supplied to the back surface of the substrate W through the opening 24 of the spin chuck 13 to obtain the substrate. Wash the backside of W.

When the time T1 has elapsed, the supply of pure water from the double pipe 28 is stopped. Then, the rotation speed of the spin chuck 13 is increased to rotate the substrate W at a high speed. At this time, the substrate W is rotated at a rotation speed of, for example, about 2000 rpm so that the cleaning liquid attached to the substrate W can be shaken off at high speed. Further, the time T2 during which the rotation speed is maintained is preferably, for example, about ten and several seconds to 30 seconds.

When the substrate W is rotated at a high speed, the droplets of the processing liquid remaining on the surface of the substrate W are shaken off from the surface of the substrate W by the centrifugal force, and are directed outward from the surface of the substrate W. Although scattered, the height H of the scattering prevention cup 15 is set to be equal to or higher than the maximum reaching height of the droplet, so that the droplet does not reach the outside of the scattering prevention cup 15. Therefore, it is possible to completely prevent the processing liquid from being scattered to the outside even when a shutter or the like is not provided outside the scattering prevention cup 15.

When the substrate W is rotated at a high speed, the processing liquid scattered from the substrate W collides with the scattering prevention cup 15 to generate fine droplets (mist), but the scattering prevention cup 15 Since a uniform downward airflow is formed inside by the exhaust port 39, the liquid droplets are discharged out of the system together with the downward airflow, and do not diffuse from the shatterproof cup 15 to the outside. Particularly, in this embodiment, since the four exhaust ports 39 are arranged in the circumferential direction substantially equally with respect to the rotary shaft 27, a uniform downward flow is formed in the scattering prevention cup 15, It becomes possible to reliably discharge fine droplets.

Then, by driving the air cylinder 37,
The nozzle 35 of the gas supply means 14 is moved from the standby position shown by the solid line in FIGS. 2 and 3 to the gas supply position shown by the chain double-dashed line. As a result, the tip of the nozzle 35 moves to a position approaching a few mm above the center of rotation on the surface of the substrate W held by the spin chuck 13 and rotating. In this state, the nitrogen gas is supplied from the conduit 36 to the nozzle 35, so that the nitrogen gas is blown toward the rotation center of the rotating substrate W. By supplying this nitrogen gas, the cleaning liquid remaining near the center of the substrate W is removed and its drying is promoted.

In parallel with the above-mentioned supply of nitrogen gas to the surface of the substrate W, nitrogen gas is supplied from the nitrogen gas supply pipe 32 to the double pipe 28, and this nitrogen gas is supplied from the double pipe 28 to the spin chuck 13. By spraying on the back surface of the substrate W through the opening 24, the drying of the back surface of the substrate W is promoted like the front surface of the substrate W.

When the time T2 has passed and the drying of the substrate W is completed, the spin chuck 13 is stopped from rotating and the nozzle 3
Move 5 to the standby position. Then, the substrate W on the spin chuck 13 is sandwiched by the second chuck 17 and placed on the transport roller 12 of the substrate unloading unit 4, and is transported by the transport roller 12 to the subsequent processing step.

In the above-described embodiment, the case where the present invention is applied to the rotary type substrate drying apparatus used in the step of drying the substrate W has been described, but the cleaning brush is brought into contact with the surface of the rotating substrate W. After the step of cleaning the substrate W or the step of supplying the cleaning liquid to which ultrasonic waves are applied to the surface of the substrate W to clean the substrate W, the substrate W is rotated and dried.
It is also possible to apply the present invention to a rotary substrate drying apparatus that also has the cleaning function.

Further, in the above-mentioned embodiment, the rotation speed of the spin chuck 13 is changed from 200 rpm to 2000 r.
Although the rotation speed is increased to pm in two steps, the rotation speed may be continuously increased from the low speed rotation to the high speed rotation.

Further, in the above embodiment, the case where the processing is performed on the glass substrate W for the rectangular liquid crystal display panel has been described. However, the present invention can be applied to an apparatus for processing a semiconductor wafer. it can.

[0038]

According to the invention described in claims 1 and 2, it becomes possible to reliably capture the droplets of the processing liquid scattered from the substrate by the scattering prevention cup. Therefore, it is not necessary to dispose a shutter or the like around the rotary substrate drying device, and the substrate can be dried quickly with a simple configuration.

According to the third aspect of the present invention, since the substrate is rotated at a low speed and then at a high speed, a large amount of the processing liquid adhering to the substrate can be made to flow out from the edge of the substrate W in advance. Therefore, it is possible to prevent the liquid jump from occurring due to the scattering of a large amount of the processing liquid.

[Brief description of the drawings]

FIG. 1 is a plan view of a substrate processing apparatus to which a rotary substrate drying apparatus according to the present invention is applied.

FIG. 2 is a side view of the rotary substrate drying apparatus according to the present invention.

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is a time chart showing a rotation state of a spin chuck.

[Explanation of symbols]

 3 Rotating Substrate Drying Device 13 Spin Chuck 15 Scatter Prevention Cup 26 Motor W Substrate θ Elevation Angle

Claims (3)

[Claims] 1. A liquid droplet adhering to the substrate is shaken off by rotating a supporting means for supporting the substrate in a posture in which the surface thereof is horizontal, around a vertical axis, and liquid droplets scattered from the substrate are removed. In a rotary substrate drying device that receives a cylindrical anti-scattering cup arranged so as to surround the supporting means, the height of the anti-scattering cup is the maximum arrival height of the droplet at that position. A rotary substrate drying apparatus having the above height. 2. The rotary substrate drying apparatus according to claim 1, wherein an elevation angle from the center of rotation on the surface of the substrate to the upper end portion of the scattering prevention cup is 10 degrees or more. 3. The rotary substrate drying apparatus according to claim 1, wherein the supporting means is rotated at a low speed for a predetermined time and then at a high speed.