JP3032428B2 - Liquid supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for manufacturing electronic parts (hereinafter simply referred to as a substrate) such as a semiconductor wafer, a glass substrate for manufacturing a liquid crystal display device, a glass substrate for a photomask, and a substrate for an optical disk. And a liquid supply device for supplying a liquid such as a polyimide resin liquid and a photoresist liquid.

[0002]

2. Description of the Related Art In an electronic component manufacturing process, for example, a substrate such as a semiconductor wafer or a glass substrate is held in a horizontal posture,
2. Description of the Related Art A desired liquid is applied to a substrate surface by supplying a desired liquid to the substrate and rotating the liquid around a vertical axis. In such a process, a liquid supply device that supplies a predetermined amount of liquid in a predetermined container to the surface of the substrate is used.

For example, when a polyimide resin liquid or a high-viscosity photoresist liquid is targeted, an apparatus as shown in FIG. 4 is conventionally used. In FIG. 4, reference numeral 2 denotes a chuck for sucking and holding the substrate W in a horizontal posture, 4 a motor for rotating and driving the chuck 2, and 6 a surplus liquid surrounding the held substrate W to collect excess liquid and scatter to the periphery. It is a cup to prevent. 10 is a bottle with an open top that contains a polyimide resin liquid, 12 is a pressurized container that contains the bottle 10, 14
Is a pressurizer that feeds pressurized nitrogen gas (N ₂ ) into the pressurized container 12 via the pressurized pipe 16. Reference numeral 18 denotes a chemical pipe inserted near the bottom of the bottle 10, reference numeral 20 denotes a nozzle provided at the tip of the chemical pipe 18 for discharging a liquid to the substrate W on the chuck 2, and reference numeral 22 denotes a chemical liquid pipe 18. The air valve 24 is a suck-back valve that is inserted into the chemical liquid pipe 18 and that pulls back the liquid remaining in the nozzle after discharging a predetermined amount of liquid to prevent the remaining liquid from being undesirably dropped onto the substrate W. . Reference numeral 26 denotes a control unit for controlling the motor 4, the air valve 22, and the suck-back valve 24. Reference numeral 28 denotes a control unit.
On the other hand, an input unit comprising a keyboard for inputting data such as an amount of liquid discharged at one time, and a display unit 30 for displaying data output from the control unit 26, an alarm and the like.

In such an apparatus, the liquid in the bottle 10 is pressurized at a predetermined pressure, and an amount of liquid is discharged onto the substrate W in accordance with the time during which the air valve 22 is opened. The operator operates the input unit 28 to input data such as the amount of liquid in the bottle 10 and the amount of liquid to be discharged at one time to the control unit 26 in advance. The control unit 26 performs one opening time and timing of the air valve 22 based on the data,
The application of the liquid to the substrate W is performed by controlling the number of revolutions of the motor 4 and the like. At this time, the control unit 26 accumulates and stores the number of times the air valve 22 is opened according to a control program given in advance, calculates the used amount of the liquid by multiplying the number of times by the discharge amount of the liquid once, and The remaining amount in the bottle 10 is calculated. When the remaining amount in the bottle 10 decreases, the fact is displayed on the display unit 30 to urge the operator to replenish the liquid, replace the bottle 10, and the like.

In such an apparatus, the remaining amount of liquid is calculated based on data such as the amount of liquid in the bottle 10 and the amount of liquid discharged at one time, which are manually input by an operator. In addition, since the liquid in the bottle 10 is insufficient, there is a possibility that the discharge amount is insufficient or the liquid containing bubbles is supplied to the substrate W. In addition, if a piping configuration as shown in FIG. 4 is used for a polyimide resin solution or a high-viscosity photoresist solution, gas may enter the chemical solution piping 18 for some reason such as a shortage of liquid in the bottle 10. If the bottle 10 has been dropped or the bottle 10 needs to be replaced with a new one, all the liquid in the chemical solution pipe 18 up to the nozzle 20 must be discarded in order to bleed the pipe.
Therefore, a large amount of expensive chemicals must be discarded to remove air, which is uneconomical. Further, in order to prevent gas from entering into the chemical solution pipe 18 due to lack of liquid in the bottle 10, it is necessary to replace the bottle as soon as possible in anticipation of considerable safety before the lack of liquid in the bottle 10. Alternatively, work such as replenishment of the liquid must be performed, which complicates the work.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and can reliably detect the presence of gas in a pipe. The amount of liquid to be discarded for bleeding can be reduced, so that the liquid can be reliably supplied without complicating the work, and the amount of liquid to be discarded at the time of bleeding can be reduced. It is an object to provide a liquid supply device with low cost.

[0007]

According to the present invention, there is provided a delivery means for sending a liquid in a container to a first pipe, and a branch means for branching the first pipe into a second pipe and a third pipe. A nozzle connected to the second pipe and supplying a liquid supplied from the second pipe to the substrate; a waste pipe connected to the third pipe; and a second pipe and the third pipe. and closing means for opening and closing the piping, and detecting means for detecting the gas within the first pipe, the gas emitted by the detection means
After receiving the detection signal, open / close
By opening and closing the step, the second pipe is closed for a predetermined time and the third pipe is closed.
And a control unit for opening the piping of the liquid supply device.

[0008] The present invention also provides the first detecting means,
The first section from the pipe detection site to the branching means.
The capacity of the pipe, and larger than the liquid discharge amount once before
The control means is activated by the detection means during the liquid supply.
After receiving the detection signal of the discharged gas.
Cormorant that the liquid supply device according to claim 1, wherein.

[0009]

According to the first aspect of the present invention, the gas present in the first pipe is detected by the detecting means. When a gas exists in the first pipe, the control unit outputs a gas detection signal.
Open / close the opening / closing means by inputting the bottle replacement after receiving
To close the second pipe for a predetermined time and open the third pipe
Good. When the first pipe is connected to the third pipe by the opening / closing means, the gas is discharged from the third pipe to the waste liquid pipe. Since the branching means for branching the first pipe into the second pipe and the third pipe is provided at a position closer to the container than the nozzle, the gas is discarded when discharging the gas through the third pipe. Only a small amount of liquid is needed.

According to the second aspect of the present invention, the capacity of the first pipe between the detection portion of the first pipe by the detecting means and the branching means is set to be larger than one liquid discharge amount. Therefore, even when the detection unit detects gas in the middle of one liquid ejection, it is possible to perform an operation of discharging the gas from the third pipe after completing the one liquid ejection. it can. In such a case, the gas does not pass through the branching means and enter the second pipe during the single liquid ejection, and the gas can be reliably discharged from the third pipe. Moreover, there is no need to interrupt the processing of the substrate which was in the middle of the one processing, and the substrate is not wasted.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coating apparatus using a liquid supply apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view of a main part showing a first embodiment of the present invention. In the description of this embodiment, the same or corresponding parts as those of the conventional example described above are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, reference numeral 41 denotes a first pipe inserted near the bottom of the bottle 10 containing the polyimide resin liquid, and reference numeral 44 denotes a first pipe 41 formed by connecting a second pipe 42 and a third pipe 43 to each other. This is a three-way joint that branches off. Second pipe 42
Is the first air valve 46 and the suck back valve 24
Is inserted and connected to the nozzle 20. Reference numeral 48 denotes a waste liquid pipe which communicates with a waste liquid processing device (not shown). The third pipe 43 has a second air valve 50 interposed therein and the waste liquid pipe 4.
8 is connected. All of the first pipe 41, the second pipe 42, and the third pipe 43 are made of substantially colorless and transparent Teflon tubes.

[0013] 52 is provided in the middle of the first pipe 41,
This is a transmission type sensor that detects the presence or passage of gas or air bubbles at the corresponding location in the first pipe 41. Sensor 52
As shown in FIG. 2, a light-emitting element 54 and a light-receiving element 5 are provided so as to face each other with the first pipe 41 interposed therebetween.
And 6. The sensor 52 is connected to the control unit 26 to transmit a detection signal, and the control unit 26 controls the first air valve 46, the second air valve 50, the suck back valve 24, and the motor 4 with reference to the signal.

The distance L from the sensor 52 to the three-way joint 44 from the detection position of the first pipe 41 is set as follows. That is, in the first pipe 41, the capacity of the portion between the points L is set so as to be larger than one liquid ejection amount. For example, the substrate W to be coated
Is a semiconductor wafer having a diameter of 8 inches, when applying the polyimide resin liquid, the discharge amount of the liquid, that is, the polyimide resin liquid per discharge is about 8 grams (about 7.2 cc). With some allowance, the capacity of the portion between L is set to about 12 grams (about 10.8 cc) or more. Correspondingly, in this embodiment, a Teflon tube having an inner diameter of 6 mm is used as the first pipe 41, and the length of the L is set to about 45 cm or more.

In the apparatus having the above configuration, the bottle 1
The liquid in 0 is pressurized at a predetermined pressure, and both the first air valve 46 and the second air valve 50 are normally closed. Then, when the first air valve 46 is opened, an amount of liquid corresponding to the opening time is discharged onto the substrate W through the first pipe 41, the three-way joint 44, and the second pipe 42.
When the discharge of the prescribed amount is completed, the first air valve 46 closes, and at the same time, the suck-back valve 24 is operated, and the residual liquid in the nozzle 20 is slightly pulled back. Prevent desired dripping. Normally, such an operation is repeated.

During the repetition of the processing, the liquid in the bottle 10 may decrease, the liquid level may drop to near the tip of the first pipe 41, and bubbles may enter the first pipe 41. When the liquid containing bubbles is discharged to the substrate W in this manner, the amount of the discharged liquid becomes smaller than a predetermined amount, or the film applied due to the bubbles becomes uneven.
In the present apparatus, when such a bubble passes through the location of the sensor 52 in the first pipe 41, the sensor 52 detects the presence of the bubble and issues a detection signal to the control unit 26. When receiving the detection signal, the control unit 26 displays the detection signal on the display unit 30 to confirm the remaining amount in the bottle 10, replenish the liquid, and replace the bottle 10 with the operator.
When the operator replaces the bottle 10 with a new one containing a sufficient amount of liquid, and inputs the fact from the input unit 28, the control unit 26 closes the first air valve 46 and turns the second air valve 50 to a predetermined position. Open only for hours. As a result, the liquid containing bubbles is discharged from the first pipe 41 through the three-way joint 44 to the waste liquid pipe 48 together with the bubbles. After a lapse of a predetermined time, the second air valve 50 is closed to prepare for the next liquid discharge. The predetermined time during which the second air valve 50 is opened is set by the operator arbitrarily setting the operation time of the timer function built in the control unit 26.

As described above, the substrate W is a semiconductor wafer having a diameter of 8 inches, and bubbles are generated during the first (about 7.2 cc) discharge of the liquid as described above.
It is assumed that the vehicle has passed the location where the first sensor 52 is installed, and the sensor 52 has detected the passage of the bubble. In this case, in the present apparatus, the distance L between the detection part of the first pipe 41 by the sensor 52 and the three-way joint 44 is set to be about 10. Since the length is set to 8 cc, even if the one-time discharge is completely completed, bubbles detected by the sensor 52 pass through the three-way joint 44 and enter the second pipe 42. I won't. Therefore, even in this case, it is not necessary to interrupt the single discharge, the first air valve 46 is closed after the single discharge is completely completed, the bottle 10 is replaced thereafter, and the like. The second air valve 50 may be opened. Thus, the bubbles can be discharged from the third pipe 43 without reaching the second pipe 42 and without forgetting the processing of the substrate W that is the target of the discharge.

The overall length of the pipe from the end of the first pipe 41 in the bottle 10 to the nozzle 20 is, for example, about 400 cm in a general apparatus, and in a conventional apparatus, it is necessary to release air. Although it was necessary to discard all the liquid remaining in the whole, in the present invention, the first pipe 4
1, the air bleeding can be completed only by discarding the liquid of about 45 cm indicated by L in the figure, so that the amount of liquid wastefully discarded at the time of air bleeding is reduced by about 1/8.
The present invention significantly contributes to a reduction in the running cost of the apparatus. In addition, since the presence of gas in the pipe can be reliably detected by the sensor 52, the supply of the liquid containing gas to the substrate W can be reliably prevented, and the operation can be reliably performed without complicating the operation. Can supply liquid.

In the above embodiment, the bottle 10 is used as the container in the present invention, the pressurizer 14 and the pressurized container 12 are used as the delivery means, the three-way joint 44 is used as the branching means, and the first air valve 46 and the second air are used. The valve 50 corresponds to opening / closing means, and the sensor 52 corresponds to detecting means. In the above description, the decrease in the liquid in the bottle 10 has been described as a cause of the generation of air bubbles in the pipe. However, the present invention is not limited to this. For example, the nitrogen gas pressurized to send the liquid to the first pipe 41 may be a liquid. It is also conceivable that, for some reason, it may appear as bubbles in the first pipe 41, and even in such a case, the presence of bubbles and gas can be detected and discharged. Further, as the sensor 52, a transmissive sensor including the light projecting element 54 and the light receiving element 56 is used, but the present invention is not limited to this, and other optical sensors or liquids or gases in the pipes may be used. It may be a so-called capacitance sensor that detects the presence of a gas by a change in capacitance, or another type of sensor. If the liquid to be used has a high viscosity, the detection accuracy of the capacitance sensor may be reduced. In this regard, it is desirable to use an optical sensor. In addition, the delivery of the liquid is not limited to the one in the present embodiment in which the liquid is pressurized with nitrogen gas, and may be, for example, a liquid in which the liquid is pressurized by compressed air, or a liquid in which the liquid is delivered by a diaphragm pump. Also,
In the above embodiment, as the means for opening and closing the third pipe 43, the second air valve 50 that is controlled to be closed by the timer function incorporated in the control unit 26 is provided. However, the present invention is not limited to this. First pipe 41 or third pipe 4
It may be a valve that is manually closed while monitoring the state of movement of the air bubbles in 3.

FIG. 3 is a view showing a main part of a piping system according to a second embodiment of the present invention. In FIG. 3 showing the second embodiment, only portions different from the first embodiment described above are shown, and portions not shown are the same as those in the first embodiment. In the present embodiment, the first pipe 41 is connected to the three-way valve 6.
0 branches off into a second pipe 42 and a third pipe 43, and the second air valve 50 in the first embodiment is omitted. The three-way valve 60 is also controlled by the control unit 26, similarly to the first air valve 46. The other configuration is the same as that of the first embodiment, and the description is omitted.

In the second embodiment, the first
The three-way valve 60 is switched and controlled so that the first pipe 41 communicates with the second pipe 42, and the liquid is supplied to the substrate W by opening and closing the first air valve 46. When the sensor 52 detects that air bubbles have entered the first pipe 41, the control unit 26 prompts the operator to replace the bottle 10 or the like with the first air valve 46 closed. Then, after the replacement of the bottle 10 or the like, the three-way valve 60 is switched so that the first pipe 41 and the third pipe 43 communicate with each other, and the air bleeding operation is performed. After the air release, the three-way valve 60 is switched so that the first pipe 41 and the second pipe 42 communicate with each other to prepare for the next liquid discharge. This second
According to the embodiment of the present invention, the amount of wastefully discarded liquid at the time of bleeding air can be reduced, the running cost of the apparatus can be reduced, and it is ensured that the liquid containing gas is supplied to the substrate W. Liquid can be reliably supplied without complicating the operation.

In the second embodiment, the function of the second air valve 50 in the first embodiment is also used for the three-way valve 60. In this embodiment, the three-way valve 60 is a branch valve according to the present invention. Means, three-way valve 60 and first air valve 46
Correspond to the opening / closing means, respectively. Further, in the second embodiment, the components from the sensor 52 to the three-way valve 60 are:
This corresponds to the distance L in the first embodiment.

[0023]

According to the first aspect of the present invention, the presence of gas in the pipe can be reliably detected, and the amount of liquid discarded in order to release air from the pipe at that time. This makes it possible to provide a liquid supply device that can reliably supply the liquid without complicating the operation, reduce the amount of liquid discarded at the time of bleeding air, and have a low running cost.

According to the second aspect of the present invention, even if the detecting means detects a gas in the course of one liquid ejection, the gas is discharged to the third liquid after the one liquid ejection is completed. An operation of discharging from the pipe can be performed, and in such a case, the gas does not pass through the branching means and enter the second pipe during the single liquid discharge, and the third liquid is discharged. The gas can be reliably discharged from the piping of the apparatus, and there is no need to interrupt or forget the processing of the substrate which was in the middle of the single processing, and without wasting the substrate, The operation efficiency can be improved and the operation of the device can be easily performed.

[Brief description of the drawings]

FIG. 1 is a schematic view of a main part of a coating apparatus using a liquid supply device according to a first embodiment of the present invention.

FIG. 2 is a schematic sectional view showing a sensor portion of the first embodiment shown in FIG.

FIG. 3 is a schematic diagram showing a main part of a piping system according to a second embodiment of the present invention.

FIG. 4 is a schematic view of a main part showing a conventional apparatus.

[Explanation of symbols]

 Reference Signs List 10 bottle 12 pressurized container 14 pressurizer 14 41 first pipe 42 second pipe 43 third pipe 44 three-way joint 46 first air valve 50 second air valve 52 sensor 60 three-way valve

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/027 G03F ^7/ 00-7/42

Claims (2)

(57) [Claims] 1. A delivery means for delivering a liquid in a container to a first pipe; a branch means for branching the first pipe into a second pipe and a third pipe; A nozzle connected to supply a liquid supplied from the second pipe to the substrate, a waste liquid pipe connected to the third pipe, and an opening / closing means for opening and closing the second pipe and the third pipe. Detecting means for detecting gas in the first pipe, and receiving a gas detection signal emitted by the detecting means;
Opening and closing the opening / closing means by inputting a bottle replacement later
Control to close the second pipe for a predetermined time and open the third pipe
Liquid supply apparatus characterized by comprising: a part, the. The capacity of the first pipe between the wherein the detection site of the first pipe by said detecting means to said branching unit, larger than the liquid discharge volume of one, said control means
Detection of gas emitted by the detection means during liquid supply
2. The liquid supply device according to claim 1, wherein the single ejection is performed after receiving the output signal .