JP2002353189A - Drying method and drying processor for substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drying method reducing the amount of a gas, without reducing drying efficiency when drying a cleaned substrate. SOLUTION: In the drying method drying the substrate 4, cleaned by processing liquid by jetting the gas from an air knife 8 to the substrate while carrying it in a prescribed direction, the jetted amount of the gas from the air knife is controlled, corresponding to the relative position of the substrate and the air knife.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for drying a substrate for removing a processing liquid attached to the substrate with a gas.

[0002]

2. Description of the Related Art For example, in a manufacturing process of a liquid crystal display device or a semiconductor device, there are a film forming process and a photo process for forming a circuit pattern on a substrate such as a glass substrate or a semiconductor wafer. In these processes, after the substrate is treated with a predetermined chemical solution, the substrate is washed with a treatment solution such as pure water. As the substrate cleaning process, for example, megasonic cleaning for cleaning with a processing solution subjected to ultrasonic vibration is performed.

[0003] If the above substrate is cleaned with a processing solution,
A gas is sprayed onto the substrate by an air knife to perform a drying process for drying and removing the processing liquid attached to the substrate.

The chemical treatment, the cleaning treatment with the treatment liquid, and the drying treatment with the air knife in the photo process performed on the substrate are sequentially and continuously performed while the substrate is transported by transport means such as transport rollers. .

[0005]

When the substrate is dried by an air knife, the amount of gas used may increase as the substrate becomes larger. That is, as the size of the substrate increases, the amount of the processing liquid remaining on the substrate due to the cleaning process increases. Therefore, in order to remove the processing liquid remaining on the substrate, the amount of gas injected from the air knife toward the substrate must be increased. For example, when the size of the substrate is 1 m × 1 m, the gas injection amount required to dry the cleaned substrate needs to be about 3000 l / min.

However, if such a large amount of gas is constantly used during the drying process of the substrate, if the gas is used in another part of the factory, the gas is sufficiently supplied to that part. In some cases, the gas supply capacity in the factory must be greatly increased in order to solve the problem.

It is an object of the present invention to provide a method and apparatus for drying a substrate, wherein the amount of gas used for drying the substrate can be reduced without reducing the efficiency of the drying processing. is there.

[0008]

According to a first aspect of the present invention, a substrate cleaned by a processing liquid is transported in a predetermined direction.
In the drying processing method of injecting a gas from an air knife to the substrate to dry the substrate, the amount of the gas ejected from the air knife is controlled according to a relative position between the substrate and the air knife. Drying method.

According to a second aspect of the present invention, there is provided a drying method in which a substrate cleaned by a processing liquid is transported in a predetermined direction while gas is sprayed from an air knife to the substrate to dry the substrate. A first detection step of detecting that the gas has reached the gas ejection region, a first setting step of setting the gas ejection amount from the air knife based on the detection of the first detection step, and the substrate Detecting that the air knife has been transported to a predetermined position in the gas injection region by the air knife, and determining the amount of gas injection from the air knife based on the detection in the second detection step. A second setting step of reducing the injection amount from that set in the first setting step, and detecting that the substrate has been conveyed until just before it comes out of a gas injection area by the air knife. And a third setting step of increasing the injection amount of gas from the air knife over the injection amount set in the second setting step based on the detection in the third detection step. And a method for drying a substrate.

According to a third aspect of the present invention, there is provided a drying apparatus for drying a substrate which has been washed by a processing liquid by injecting gas from an air knife to the substrate while drying the substrate in the predetermined direction. Transport means for detecting that the substrate has reached the gas ejection region of the air knife, and first detection means for detecting that the substrate has been transported to a predetermined position in the gas ejection region of the air knife. Detecting means for detecting that the substrate has been transported to a position immediately before the substrate comes out of the gas injection region of the air knife, and detecting the first to third detecting means. Control means for controlling the injection amount of the gas injected from the air knife based on the above.

According to a fourth aspect of the present invention, a plurality of flow control valves provided in parallel to a pipeline for supplying gas to the air knife, and the detection of the substrate transfer position by the first to third switches. 4. The apparatus for processing a substrate according to claim 3, further comprising a control device for controlling an opening degree of said flow control valve.

According to the present invention, the amount of gas injected from the air knife is controlled in accordance with the transfer position of the substrate with respect to the air knife, so that the use of gas can be performed without lowering the efficiency of drying the substrate. The amount can be reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

The processing apparatus of the present invention shown in FIGS.
A cleaning treatment tank 1 provided adjacently and a drying treatment tank 2 constituting a drying treatment device are provided. A plurality of transport rollers 3 constituting transport means are rotatably disposed at predetermined intervals inside the cleaning tank 1 and the drying tank 2 and before and after the processing tanks 1 and 2.

Each of the transport rollers 3 is driven to rotate by a driving means (not shown), thereby transporting a substrate 4 such as a glass substrate for a liquid crystal display in the direction of an arrow.

In the cleaning tank 1, a first ultrasonic cleaner 5 is provided above a substrate 4 transported by a transport roller 3.
And the second ultrasonic cleaner 6 are arranged at a predetermined interval along the transport direction of the substrate 4.

The length of each of the ultrasonic cleaners 5 and 6 is
Is set to be longer than half of the width dimension of the substrate 4, and one end in the length direction is overlapped with the width direction of the substrate 4, so that the pair of ultrasonic cleaners 5, 6 A processing liquid such as pure water to which ultrasonic vibration has been applied over the entire length can be supplied.

In the cleaning tank 1, a single ultrasonic cleaner having a length equal to or greater than the width of the substrate 4 is provided instead of providing a pair of ultrasonic cleaners 5 and 6. It may be.

As shown in FIG. 2, the drying tank 2 has a pair of air knives 8 opposed to the upper surface and the lower surface of the substrate 4 to be conveyed at an angle θ with respect to the direction in which the substrate 4 is conveyed.
(Shown in FIG. 1). Slits 9 are formed in respective end surfaces of the air knives 8 facing the upper and lower surfaces of the substrate 4, and these slits 9 are inclined at a predetermined angle in a direction opposite to the direction in which the substrate 4 is transported.

From the slit 9 of each air knife 8, a gas such as air or an inert gas pressurized to a predetermined pressure is directed to the upper and lower surfaces of the substrate 4 in a direction opposite to the direction in which the substrate 4 is transported. Is to be injected.

The amount of gas injected from each air knife 8 is controlled by the relative position between the substrate 4 and the air knife 8. That is, the drying tank 2 shown in FIG.
As shown in FIG. 3A, a first switch 11 for detecting that the corner at one end in the width direction of the front edge 4a of the substrate 4 has reached the region of the gas ejected from the air knife 8, and FIG.
As shown in FIG. 3C, a second switch 12 for detecting that the corner at the one end in the width direction of the rear edge 4b of the substrate 4 has been transported to a position where it reaches the region of the gas ejected from the air knife 8. Are provided. The detection signals of the first and second switches 11 and 12 are input to the control device 13.

The control device 13 includes a second switch 1
A timer 10 which is activated by the detection signal of No. 2 and which times up after a predetermined time has elapsed is connected. The first and second switches 11 and 12 and the timer 10 constitute first to third detecting means for detecting the transfer position of the substrate 4.

A pipe 14 is connected to the pair of upper and lower air knives 8. A first flow control valve 15 and a second flow control valve 16 are provided in parallel at an intermediate portion of the pipe 14 communicating with a gas supply source (not shown). I have. The opening of these flow control valves 15 and 16 is controlled by the control device 13. In this embodiment, the opening of the flow control valves 15 and 16 is controlled to open and close as described later.

A pressure reducing device 18 is connected to the cleaning tank 2 as shown in FIG. The decompression device 18 maintains the cleaning tank 1 at a lower pressure than the drying tank 2 adjacent to the cleaning tank 1. This prevents the processing liquid in the form of mist from entering the drying processing tank 2 from the cleaning processing tank 1.

Although not shown, a carry-in port is formed in the cleaning tank 1, a carry-out port is formed in the drying tank 2, and a through-hole is formed in a partition wall separating the tanks 1 and 2. The port, the carry-out port, and the port are each opened and closed by a gate valve (not shown).

Next, the operation when processing the substrate 4 by the processing apparatus having the above configuration will be described.

A substrate 4, such as pure water, which has been subjected to a predetermined treatment with a chemical solution or the like in a processing section (not shown) on the upstream side of the cleaning tank 1, is carried into the cleaning tank 1 by the transport rollers 3. In the cleaning tank 1, a processing liquid to which ultrasonic vibration is applied is sprayed from the first and second ultrasonic cleaners 5 and 6 toward the upper surface of the substrate 4. Thereby, the upper surface of the substrate 4 is ultrasonically cleaned with the processing liquid.

When cleaning the substrate 4, a large amount of processing liquid is used. Therefore, a large amount of the processing liquid adheres and remains on the upper surface of the substrate 4 cleaned in the cleaning processing tank 1.

The substrate 4 cleaned by the ultrasonic cleaners 5 and 6 is carried into the drying tank 2. After loading, after _one hour T as shown in FIG. 4, one widthwise end portion of the front edge 4a of the loaded wafer 4 to drying tank 2 from an air knife 8 as shown in FIG. 3 (a) injection Is reached by the first switch 11,
The detection signal is input to the control device 13.

When the detection signal of the first switch 11 is input to the control device 13, a drive signal is output from the control device 13 to the first flow control valve 15 and the second flow control valve 16, and the drive signal is output. A pair of flow control valves 15 and 1 are driven by a drive signal.
6 is released. Thereby, a pair of air knives 8
The gas at the maximum flow rate indicated by V ₁ in FIG. 4 is supplied through the pipe 14. The surface is swept away in the direction opposite to the transport direction.

Since both the first and second flow control valves 15 and 16 are opened by the detection signal that the first switch 11 has detected the substrate 4, the amount of gas supplied to the pair of air knives 8 is This is the maximum amount of flow that can be supplied by line 14.

Therefore, when the drying process of the substrate 4 is started, a large amount of the processing liquid adheres to and remains on the plate surface of the substrate 4, but the gas is jetted from the pair of air knives 8 at the maximum flow rate V _1. In addition, the drying process of the substrate 4 can be performed reliably.

After the elapse of time t ₂ , the substrate 4 is transported to the position shown in FIG. 3C via the transport position shown in FIG. 3B while being subjected to the drying process, and this is detected by the second switch 12. . That is, when one end in the width direction of the rear edge 4b of the substrate 4 reaches the ejection area of the gas ejected from the air knife 8, the second switch 12 detects that.

When the second switch 12 detects the substrate 4, the control device 13 closes the second flow control valve 16 based on the detection signal, and determines the amount of gas injected from the pair of air knives 8 in FIG. as shown by _two to half of the maximum flow rate V _1.

As a result, the gas ejected from the air knife 8 gently flushes the processing liquid remaining on the substrate 4, so that the processing liquid splashes at the rear edge 4 b of the substrate 4 in the transport direction as in the case of vigorously wiping the processing liquid. Is prevented. That is,
The treatment liquid is prevented from splashing on the rear edge 4b of the substrate 4 and re-adhering to the dried portion of the substrate 4.

Moreover, since the amount of gas supplied to the air knife 8 can be halved, the amount of gas used can be greatly reduced. Further, when one end in the width direction of the rear edge 4b of the substrate 4 reaches the ejection area of the air knife 8, the amount of the processing liquid remaining on the upper surface of the substrate 4 is significantly reduced as compared with the time when the drying process is started. since it is, even if half the supply amount of the gas at that time V ₂ from V _1, does not adversely affect the drying processing of the substrate 4. That is, the substrate 4
There is no decrease in the efficiency of drying.

When the second switch 12 detects that the substrate 4 has been transported to a predetermined position, the timer 10 connected to the control device 13 starts operating from that point. Timer 10
When There predetermined time has elapsed as indicated by T ₃ in FIG. 4 in operation, the portion which is not dried by the gas injected from the air knife 8 as shown in FIG. 3 (d) the rear edge 4b of the substrate 4 At the other end in the width direction.

Elapsed time T when timer expires₃so
Is controlled by the drive signal from the control device 13
The control valve 16 is opened and the pair of air knives 8 flows to the maximum.
Quantity V ₁Is supplied. Thereby, after the substrate 4
The processing liquid pushed to the other end in the width direction of the edge 4b is thereafter
It will be surely removed from the edge 4b.

That is, as described above, from the time when one end in the width direction of the front edge 4a of the substrate 4 reaches the gas injection region of the air knife 8 to the time when one end in the width direction of the rear edge 4b reaches. During this period, the gas injection amount is maximized, and thereafter, the gas injection amount is set to a half of the maximum time until the portion that has not been dried is only the other end in the width direction of the rear edge 4b of the substrate 4, and When the other end in the width direction of the rear edge 4b of the substrate 4 was subjected to the drying process, the gas injection amount was again maximized.

Therefore, the amount of gas used can be significantly reduced as compared with the case where the drying process is performed by always maximizing the gas injection amount. In addition, the timing of reducing the gas injection amount is when the amount of the processing liquid is reduced as compared with the case where the processing liquid adheres and remains on the entire surface of the substrate 4. In addition, the processing liquid remaining on the substrate 4 can be reliably removed, and the substrate 4 can be dried.

The present invention is not limited to the above embodiment, but can be variously modified. For example, two flow control valves are provided in parallel in a pipeline in order to adjust the gas supply amount, but the number may be three or more. The amount can be controlled to be reduced to one third or two thirds of the maximum injection amount.

Further, when the timer operated by the detection signals of the first switch, the second switch, and the second switch times out that the substrate has been transported to the predetermined position, the gas for drying the substrate is processed. Although the injection amount is controlled, a third switch may be used to detect that the substrate has been transported to a predetermined position instead of the timer.

If the switch detects that the substrate has been transported to the predetermined position for the first time, the timer is activated by the detection signal of the switch, and thereafter, based on the set time set in the timer. The gas injection amount may be controlled. In other words, since the transfer speed of the substrate by the transfer roller is constant, if the position of the substrate is first detected by the switch, the transfer position of the substrate is detected according to the elapsed time of the timer, and the gas injection amount is controlled. It is possible to do.

[0044]

According to the present invention, the amount of gas injected from the air knife is controlled in accordance with the position of the substrate transferred to the air knife.

Therefore, it is possible to reduce the amount of gas used without lowering the drying processing ability of the substrate.

[Brief description of the drawings]

FIG. 1 is a plan view of a processing apparatus according to an embodiment of the present invention.

FIG. 2 is a side view of the processing apparatus.

FIG. 3 is a diagram for explaining a relationship between a relative position between an air knife and a substrate and a gas injection amount.

FIG. 4 is a time chart showing a relationship between a substrate transfer position and a gas injection amount.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 3 ... Conveyance roller (conveyance means) 4 ... Substrate 8 ... Air knife 11 ... 1st switch 12 ... 2nd switch 13 ... Control device 14 ... Pipe line 15 ... 1st flow control valve 16 ... 2nd flow control valve

Claims (4)

[Claims] 1. A drying processing method for injecting gas from an air knife to a substrate and drying the substrate while transporting the substrate cleaned by the processing liquid in a predetermined direction. A method for drying a substrate, wherein the method is controlled according to a relative position between the substrate and the air knife. 2. A method for drying a substrate by jetting a gas from an air knife onto the substrate while transporting the substrate cleaned by the processing liquid in a predetermined direction, wherein the substrate is placed in a gas injection region of the air knife. A first detection step of detecting that the air has arrived; a first setting step of setting the amount of gas injected from the air knife based on the detection of the first detection step; A second detection step of detecting that the gas has been conveyed to a predetermined position in the gas injection area; and a first setting step of determining a gas injection amount from the air knife based on the detection of the second detection step. A second setting step of reducing the injection amount from the injection amount set by the air knife, and a third detection step of detecting that the substrate has been transported until immediately before the substrate comes out of a gas injection region by the air knife. And a third setting step of, based on the detection in the third detection step, increasing the injection amount of the gas from the air knife above the injection amount set in the second setting step. A method for drying a substrate. 3. A drying apparatus for drying a substrate washed by a processing liquid by spraying a gas from an air knife onto the substrate while transporting the substrate in a predetermined direction, comprising: a transport unit configured to transport the substrate in a predetermined direction; First detection means for detecting that the substrate has reached the gas ejection region of the air knife; and second detection for detecting that the substrate has been transported to a predetermined position in the gas ejection region of the air knife. Detecting means for detecting that the substrate has been conveyed until just before the substrate deviates from the gas injection area by the air knife; and detecting the air based on the detection by the first to third detecting means. A drying unit for drying the substrate, comprising: a control unit configured to control an injection amount of gas injected from the knife. 4. The control means includes: a plurality of flow control valves provided in parallel with a pipe for supplying gas to the air knife; and a first to third detection means for detecting a substrate transfer position. 4. The apparatus for processing a substrate according to claim 3, further comprising: a control device that controls an opening degree of the flow control valve based on the control information.