JPH11245226A - Resist regenerating system and resist regenerating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a regenerative system and a regenerative method which can attempt the effective utilization of a resist. SOLUTION: This resist regenerating system 100 is equipped with a regeneration container 12 for regenerating a resist recovered from a resist applicator, a solvent removing apparatuses 26, 28 for evaporating the solvent component of the resist R in the container 12 to remove part of the solvent component, and a controller 24 for controlling the operation of the apparatuses 26, 28, which are operated to remove the solvent component from the resist until the viscosity of the resist reaches a target value which allows the resist to be used again by the controller 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a resist reproducing system and a reproducing method, and more particularly to a resist reproducing system and a reproducing method used in lithography and the like used in semiconductor manufacturing.

[0002]

2. Description of the Related Art In lithography and the like used in semiconductor manufacturing, a coating operation for applying a resist to a base surface is performed. This coating operation is generally performed using a spin coating type resist coating apparatus. In a spin coating type resist coating apparatus, a substrate having an underlayer is spin-chucked, and then several cc of resist is dropped at the center of the underlayer. Furthermore, the substrate is rotated, and the resist dropped at the center of the base surface is spread over the entire base surface by centrifugal force to form a resist coating on the base surface.

[0003]

At this time, the resist remaining as a film on the base surface is only a few percent of the dropped resist, and most of the resist jumps out of the substrate due to centrifugal force. The resist that jumps out (spins out) is collected as a waste liquid and is discarded as industrial waste.

For example, when a resist film having a thickness of about 1 μm is formed on the surface of a wafer having a diameter of 6 inches as a substrate,
The amount of resist used as a coating is about 0.018 cubic cm. When the coating is a liquid film, the amount of the resist used as the coating is several times this value. However, since the amount of the resist dropped on the wafer surface as the base surface is 2 to 3 cc, in any case, at least 97 to 98
The percent is spinned out from the wafer surface, collected in the collection container, and discarded as waste liquid.

[0005] The situation in which most of the resist is discarded without being effectively used is not preferable from the viewpoint of cost reduction, effective use of resources, and environmental pollution due to waste liquid.

[0006] For this reason, the emergence of a reproduction system capable of effectively utilizing the resist is desired.

According to the present invention, after a film is formed with a resist, a cleaning solution such as an edge rinse and a back rinse used for cleaning an edge and a back surface of a base is the same component as a solvent of the resist and is recovered as a waste liquid. The resist is
It is made by paying attention to the fact that the resist is diluted by the cleaning liquid. Then, by removing a predetermined amount of a cleaning liquid (solvent) from the resist collected as a waste liquid, the collected resist is made reusable, and the resist is effectively used.

[0008]

According to the present invention, there is provided a resist regenerating system comprising: a regenerating container for storing and regenerating a resist recovered from a resist coating apparatus; and a part of the solvent component evaporating a solvent component from the resist in the regenerating container. And a control device for controlling the operation of the solvent removing device. In this resist regeneration system, the controller operates the solvent removing device to remove the solvent component from the resist until the viscosity of the resist reaches the reusable target viscosity.

According to such a configuration, a part of the solvent component is removed from the recovered resist, and the viscosity of the recovered resist increases to a reusable viscosity (target viscosity).

In practicing the present invention, a weight measuring device for measuring the weight of the resist in the recycling container may be provided, and the control device may operate the solvent removing device based on the measurement result of the weight measuring device. .

According to such a configuration, the operation of the solvent removing device is controlled based on the weight of the resist.

In practicing the present invention, the controller calculates the target weight of the resist after removing the solvent component based on the viscosity and weight of the resist before removing the solvent component and the target viscosity of the resist, and calculates the weight of the resist. May be configured to operate the solvent removing device so that the target weight becomes the target weight.

According to such a configuration, if the viscosity of the resist before removing the solvent component, that is, the viscosity of the recovered resist is input, the solvent is automatically removed until the resist reaches the target viscosity.

In practicing the present invention, it is preferable that the solvent removing device includes a heating device for heating the resist in the recycling container.

According to such a configuration, the solvent is efficiently removed by heating the resist by the heating device.

In practicing the present invention, it is preferable that the solvent removing device includes a stirring device for stirring the resist in the regeneration container.

According to such a configuration, the solvent is efficiently removed by stirring the resist by the stirring device.

Further, in practicing the present invention,
It is preferable that the regeneration container is housed in a closed regeneration chamber, and an exhaust device for exhausting the interior of the regeneration chamber is provided.

According to such a configuration, the solvent is efficiently removed from the resist. Also, by appropriately treating the gas in the regeneration chamber exhausted by the exhaust device,
Solvent gas does not fill the space where the resist regeneration system is installed.

In practicing the present invention, a configuration may be adopted in which a nitrogen gas source for supplying nitrogen gas is provided in the regeneration chamber.

According to such a configuration, the inside of the regeneration chamber is in a nitrogen atmosphere. As a result, the recovered resist is regenerated in the regeneration chamber without coming into contact with air. For this reason, mixing of moisture into the resist is suppressed.

In practicing the present invention, a solvent supply device for adding a solvent to the resist in the regeneration container may be provided, and the control device may control the operation of the solvent supply device. In this configuration, the control device controls until the resist from which the solvent component has been removed by the solvent removal device has a predetermined viscosity.
The solvent supply device is operated so as to add a solvent to the resist.

According to such a configuration, the viscosity of the resist is adjusted again by adding the solvent to the resist from which the solvent has been removed, so that the viscosity can be adjusted with higher precision.

In practicing the present invention, the control device may be configured to control the operation of the solvent supply device based on the measurement result of the weight measurement device.

Further, in practicing the present invention, the control device determines a viscosity based on the viscosity and weight of the resist from which a part of the solvent component has been removed and a target viscosity after the addition of the solvent.
The weight of the resist after the addition of the solvent may be calculated, and the solvent supply device may be operated so that the weight of the resist becomes the target weight after the addition of the solvent.

According to such a configuration, if the viscosity of the resist from which a part of the solvent component is removed is inputted, the solvent is automatically added until the resist has a predetermined viscosity.

Further, according to another aspect of the invention of the present application, the resist recovered from the resist coating apparatus is housed in a regenerating container, and the solvent component is evaporated from the resist in the regenerating container to reuse the viscosity of the resist. Provided is a method for regenerating a resist which increases the viscosity to a target viscosity.

According to such a configuration, a part of the solvent component is removed from the recovered resist by evaporation, and the viscosity of the recovered resist increases to a reusable viscosity (target viscosity).

In practicing the present invention, it is preferable that the solvent component is evaporated until the resist in the regeneration container reaches the target weight.

According to such a configuration, the operation of the solvent supply device is controlled based on the weight of the resist in the regeneration container.

In practicing the present invention, the target weight of the resist may be calculated based on the viscosity and weight of the resist before removing the solvent component and the target viscosity of the resist.

In practicing the present invention, the solvent component may be evaporated while heating the resist in the regeneration container.

According to this structure, the solvent is efficiently removed by heating the resist.

In practicing the present invention, the solvent component may be evaporated while stirring the resist in the regeneration container.

According to such a configuration, the solvent is efficiently removed by stirring the resist.

Further, in carrying out the present invention, the regeneration container is housed in a closed regeneration chamber, and the solvent component is evaporated while supplying nitrogen gas into the regeneration chamber and exhausting the interior of the regeneration chamber. It may be configured.

According to such a configuration, the solvent is efficiently removed from the resist. Further, since the inside of the reproduction chamber is in a nitrogen atmosphere, the collected resist is reproduced in the reproduction chamber without coming into contact with air. For this reason, mixing of moisture into the resist is suppressed. Furthermore, by appropriately treating the exhausted gas in the regeneration chamber, the solvent gas does not fill the space in which the resist regeneration is performed.

In practicing the present invention, a configuration may be adopted in which a solvent is added to the resist whose viscosity has been increased.

According to such a configuration, the viscosity of the resist is adjusted again by adding the solvent to the resist from which the solvent has been removed, so that the viscosity can be adjusted with higher precision.

[0040]

Embodiments of the present invention will be described below in detail with reference to the drawings. The drawings merely schematically show the sizes, shapes, and arrangements of the components so that the present invention can be understood. Therefore, the present invention is not limited to the embodiment shown in the drawings.

<First Embodiment> FIG. 1 is a drawing schematically showing a configuration of a resist reproducing system 100 according to a first embodiment of the present invention.

The resist regenerating system 100 removes a part of the solvent component from the resist recovered as waste liquid by operating the solvent removing device, and removes the solvent.
This is a system that increases the viscosity of the resist (increases the viscosity) so that the collected resist can be reused. Therefore, during thickening, the weight of the resist decreases. In the resist reproduction system 100, while monitoring the weight of the resist,
When thickening is performed and the weight of the resist decreases to a target value (target weight), it is determined that the resist has been thickened to a desired viscosity (target viscosity), and the thickening is terminated.

First, the configuration of the resist reproduction system 100 will be described. The resist regenerating system 100 includes a collecting container 10 for storing the resist collected as a waste liquid, a regenerating container 12 for regenerating the collected resist, and a regenerating resist container 14 for storing the regenerated resist.
The collection container 10 stores the resist collected from a separate resist coating device (not shown). The recovered resist is diluted by edge rinse, back rinse, etc.
Its viscosity is lower than the usable viscosity. The regeneration container 12 is disposed in a closed regeneration chamber 16.

The collection container 10 and the regeneration container 12 are connected by a pipe 18. A first pump 20 and a first filter 2 are sequentially connected to the pipe 18 from the collection container 10 side.
2 are provided. Therefore, the resist regeneration system 100 is configured such that the resist in the collection container 10 can be transferred to the regeneration container 12 by the first pump 20 while being filtered by the first filter 22.

The regeneration container 12 is placed in the regeneration chamber 16
It is arranged on the weight sensor 24. The resist regeneration system 100 is configured to constantly monitor the weight of the resist R in the regeneration container 12 by the weight sensor 24.

A heating device 26 is provided adjacent to the regeneration container 12. The resist regeneration system 100 is configured so that the heating device 26 can heat the resist R in the regeneration container 12 to a predetermined temperature. The predetermined temperature is, for example, a temperature of about 30 to 40 ° C. Preferred examples of the heating device 26 include a hot plate and a thermostat. By heating the resist by the heating device 26,
Evaporation of the solvent component from the resist is promoted. The heating device 26 constitutes a part of the solvent removing device.

Further, the resist regenerating system 100 includes a stirring device 2 for stirring the resist R in the regenerating container 12.
8 are provided. The stirring device 28 includes a propeller-shaped or screw-shaped stirring member 28a that is rotated in the resist R, and a driving device 28 that rotationally drives the stirring member 28a.
b. However, the stirring device may have another configuration. Stirring of the resist by the stirrer 28 promotes evaporation of the solvent component from the resist. The stirring device 28 constitutes a part of the solvent removing device.

The recycle container 12 is provided with a temperature measuring device 30 for measuring the temperature of the resist R in the recycle container 12.

The recycled container 12 and the recycled resist container 14 are connected by a pipe 32. A second pump 34 and a second pump 34 are sequentially connected to the pipe 32 from the regeneration container 12 side.
A filter 36 and a cooling device 38 are provided.
As described above, the resist regeneration system 100 filters the resist regenerated in the regeneration container 12 with the second filter 36, and then cools the resist to the room temperature with the cooling device 38.
The second pump 34 is configured to be able to transfer to the regenerated resist container 14.

An exhaust device 40 is attached to the regeneration chamber 16. The evacuation device 40 is a suction or decompression device such as an evacuation pump.
The gas such as the solvent vapor in 6 is discharged out of the regeneration chamber 16. By the operation of the exhaust device 40, evaporation of the solvent from the resist R in the regeneration container 12 is promoted.

Further, a nitrogen gas source 41 is connected to the regeneration chamber 16. The nitrogen gas source 41 is configured to supply nitrogen gas into the regeneration chamber 16. Therefore, by operating the exhaust device 40 while operating the nitrogen gas source 41, the inside of the regeneration chamber 16 is purged by the nitrogen gas. As a result, the regeneration of the resist in the regeneration container 12 is performed in a nitrogen atmosphere.

The resist reproduction system 100 includes:
A control device 42 for controlling the operation of the entire system is provided.

The control device 42 is connected to an input device 44 through which an operator inputs necessary numerical values to the control device 42. The control device 42 includes the first pump 20 and the second pump 3
4, connected to the heating device 26, the exhaust device 40, and the nitrogen gas source 41, and configured to control the operation thereof. Further, the control device 42 determines the weight of the resist R in the regeneration container 12 monitored by the weight sensor 24,
The temperature of the resist R in the regeneration container 12 measured by the temperature measuring device 30 is input.

The controller 42 determines the target weight W2 of the resist R based on the viscosity η1 and the weight W1 of the resist R transferred to the regeneration container 12 and the viscosity (target viscosity) η2 of the resist to be obtained in the thickening step. The thickening process is performed, and when the weight W of the resist reaches the target weight W2, it is determined that the viscosity of the resist has reached the target viscosity η2, and the thickening process is stopped. .

FIG. 2 is a block diagram showing a configuration of a main part of the control device 42. The control device 42 is configured by a microcomputer, and as shown in FIG. 2, a target weight calculation unit 420, a memory 422, and a thickening control unit 42.
4 is provided.

The target weight calculator 420 determines that the weight W1 of the resist R transferred to the regeneration container 12 is the weight sensor 24.
The viscosity η1 of the resist R transferred to the regeneration container 12 and the viscosity (target viscosity) η2 of the resist desired to be obtained by the resist regeneration system 100 are input via the input device 44. ing. Further, the target weight calculator 420 calculates the weight W1 of the resist R.
The target weight W2 is calculated based on the viscosity η1 and the target viscosity η2.

The memory 422 stores data necessary for calculating the target weight W2.

The thickening control section 424 responds to the thickening execution command from the input device 44 and responds to the heating device 26 and the stirring device 28.
The thickening process is started by issuing a thickening execution signal for operating a solvent removing device such as the above. Further, the thickening control unit 424 compares the current weight W of the resist R in the regeneration container 12 with the target weight W2, and
Are equal, the resist R in the regeneration container 12 is
It is configured to determine that the target viscosity η2 has been reached, stop the operation of the solvent removing device such as the heating device 26 and the stirring device 28, and end the thickening process.

Next, the steps of resist regeneration performed by the resist regeneration system 100 will be described. First, the control device 4
2 operates the first pump 20 to transfer the resist in the collection container 10 to the regeneration container 12 through the pipe 18.
The resist in the collection container 10 is a resist whose viscosity has been reduced by being diluted with a cleaning liquid such as a back rinse or an edge rinse.

In the resist regeneration system 100, during the resist regeneration step, the controller 42 activates the exhaust device 40 and the nitrogen gas source 41 to purge the interior of the regeneration chamber 16 with nitrogen gas and to purge the interior of the regeneration chamber 16 with nitrogen. Atmosphere.

The resist in the recovery container 10 is the
During the transfer to the second filter 2, the first filter 22 filters the solid to remove solid impurities. In this embodiment, the resist is a positive resist. However, the present invention is also applicable to a negative resist.

The back rinse and the edge rinse are the same components as the solvent for the resist. Solvents for back rinse, edge rinse and resist are, for example, ECA (ethylene glycol monoethyl ether acetate), EL (ethyl lactate), EEP (ethyl-3-ethoxypropionate), MMP (methyl-3-methoxypropionate) Nate), MAK (methyl amyl ketone (2-heptanone)), and PGMEA (propylene glycol monomethyl ether acetate).

Next, a thickening step is performed. In this thickening step, the resist R in the regeneration container 12 is heated while being stirred, under the control of the controller 42, so that the solvent components such as back rinse and edge rinse that dilute the resist are evaporated from the recovered resist. To increase the viscosity of the resist to a reusable viscosity.

As described above, in this thickening step, the weight W of the resist R in the regeneration container 12 decreases. In the resist regeneration system 100, while the controller 42 monitors the weight W of the resist R in the regeneration container 12, the thickening process is performed, and when the weight W of the resist R decreases to the target value W2, the resist R becomes a desired one. Viscosity (target viscosity) η2
Is determined to have been increased, and the thickening step ends.

Next, the content of the thickening step performed under the control of the controller 42 will be described with reference to FIG. FIG.
It is a flowchart which shows the control content which the control apparatus performs in a thickening process.

When the transfer of the resist to the regenerating container 12 is completed, the weight W1 of the resist R in the regenerating container 12 is calculated from the weight sensor 24 by the target weight calculating unit 4 of the control unit 42.
20 (S1). Next, the viscosity η1 of the resist R in the regeneration container 12 measured by the operator
(Cp) and the target viscosity η2 (cp) of the resist are input to the target weight calculator 420 via the input device 44 (S2).

Next, the target weight calculator 420 calculates W1,
Based on η1 and η2 and the data in the memory 422, the target weight W2 is calculated (S3) and sent to the thickening control unit 424. The target weight W2 is a value obtained when a solvent component such as a back rinse is evaporated from the resist R in the regeneration container 12 during the thickening process, and the viscosity of the resist R in the regeneration container 12 reaches the target viscosity η2. This is the weight of the resist R. The method of calculating the target weight W2 will be described later. Since the resist R transferred to the regeneration container 12 contains back rinse and the like, the relationship of W1> W2 is established.

When a thickening start command is input via the input device 44, the thickening control section 424 issues a thickening execution signal (S4), and is constituted by the heating device 26, the stirring device 28 and the like. The thickening step is performed by operating the solvent removing device (S5). The thickening step is performed while monitoring the weight W of the resist R using the target weight W2 as a target value.

During the thickening process, the resist R
Is maintained at a constant temperature of, for example, 30 ° C. to 40 ° C. by the heating device 26 and the temperature measuring device 30 and is stirred by the stirring device 28. The regeneration chamber 16
Inside, a nitrogen gas is supplied from a nitrogen gas source 41, and the gas in the regeneration chamber 16 is exhausted outside the regeneration chamber 16 by the exhaust device 40. The operations of the heating device 26, the stirring device 28, the exhaust device 40, the nitrogen gas source 41, and the like are also controlled by the control device 42.

During the thickening process, the thickening control section 424 compares the weight W of the resist R in the recycling container 12 sent from the weight sensor 24 with W2 (S6). As described above, during the thickening step, the resist R in the regeneration container 12 is stirred while being maintained at a predetermined temperature. Therefore, during the thickening step, the solvent components such as the back rinse that have diluted the resist evaporate, and the viscosity η of the resist increases and the weight W decreases. W
Is greater than W2, the thickening is continued (S5). When the weight W of the resist R becomes equal to W2, the thickening control unit 424 determines that the resist R in the regeneration container 12 has been thickened to the target viscosity η2, and ends the thickening step (S7). That is, the operations of the heating device 26, the stirring device 28, and the like are stopped.

Thereafter, the second pump 34 is operated, and
The resist R in the reproduction container 12 is transferred to the reproduction resist container 14 via the pipe 32. During this process, the resist is filtered by the second filter 36, and further cooled to room temperature by the cooling device 38, whereby the thickening is completely stopped. When all the resists have been transferred to the regenerated resist container 14, the regenerating process ends.

In the resist reproduction system 100, the target weight W2 of the resist is calculated in the target weight calculator 420 as follows. FIG. 4 is a graph showing the relationship between the viscosity (vertical axis) and the weight (horizontal axis) of the resist used for this calculation. The display unit of viscosity is cp, and the display unit of weight is Kg.

This graph is created based on an experiment using the same type of resist and solvent as the resist to be regenerated. That is, this graph shows that resists having different viscosities, for example, 2 cp, 4 cp, 6 cp, 8 cp,
The resist of 0 cp and 12 cp is applied to a certain amount (for example, 10K
g) Each of them was prepared, and the viscosity and weight were measured while heating and stirring each, and the calibration curves (a) to (f) in which the changes in viscosity and weight were plotted are shown.

In the resist reproduction system 100, data corresponding to this graph is stored in the memory 422 of the control device 42.
Is stored as a map (or table). Then, the initial value η1 of the viscosity of the resist and the target viscosity η
When the weight 2 and the initial value W1 of the weight are input, the target weight calculation unit 420 calculates the target weight W2 with reference to the contents of this graph stored in the memory 422.

For example, according to the calibration curve (a) of this graph, in order to increase the viscosity of a resist having an initial weight W1 of 10 kg and an initial viscosity η1 of 2 cp to a target viscosity η2 of 6 cp. It can be seen that the thickening step of the resist should be continued until the weight W becomes 6 kg. In this way, the target weight W2 is calculated based on the initial weight value W1, the initial viscosity value η1, and the target viscosity value η2. When the initial value W1 of the weight is not 10 kg, the target weight W2 is calculated by multiplying by an appropriate coefficient.

According to the thus configured resist regenerating system 100, the viscosity η1 of the resist R contained in the regenerating container 12 is measured, and the η1 and the target viscosity η2 are simply input, and the resist recovered as waste liquid is obtained. Can be automatically increased to a desired viscosity.

The present invention is not limited to a system using the above-described W2 calculation method, but may employ another W2 calculation method. For example, the following W2 calculation method may be used.

The relationship between the concentration x of the resist and the viscosity y (cp) is represented by the following approximate expression.

Y = Aexp (Bx) (where A and B are constants) Therefore, from the viscosity (initial value) η1 of the resist in the regeneration container 12, the concentration (initial concentration) C1 of the resist R before the thickening step is calculated. Can be calculated. Similarly, the resist has the target viscosity η
The resist concentration (target concentration) C2 when the value of the resist reaches 2 (after the thickening step) can be calculated.

Since the resist concentration C represents the weight ratio of the solid components contained in the resist, C = W _solid / W (W _solid is the weight of the solid components in the resist, W is the total weight of the resist).

Therefore, C1 = W1 _solid / W1 holds for the resist before the thickening step, and C2 = W2 _solid / W2 holds for the resist after the thickening step. Here, W1 _solid is the weight of the solid component in the resist before the thickening step, and W2 _solid is the weight of the solid component in the resist after the thickening step. Since the thickening step is an operation of evaporating a liquid component (solvent component) such as an edge rinse from the resist, the weight of the solid component contained in the resist does not change before and after the thickening step. Therefore, W1 _solid is W2
Equivalent to _solid . C1 and C2 are calculated from the approximation formula, and W1 can be measured by a weight sensor or the like.

[0082] Thus, from the equation C1 = W1 _solid / W1 relates thickening process before registration, W1 _solid is calculated, and the value of the W1 _solid, after thickening step registration relates formula C2 = W2 _solid / W2 By substituting into W2 _solid , the target weight W2 can be calculated.

When this calculation method is adopted, the above-mentioned approximate expression is stored in the memory 422 of the control device 42.
Then, the target weight calculator 420 calculates the input W1, η
The target weight W2 is calculated in the above-described process using 1 and η2 and the approximate expression in the memory 422.

According to this calculation method, even if the initial value η1 of the viscosity of the resist is a value including, for example, a fraction of 2.36, the target weight W2 can be calculated accurately and quickly.

<Second Embodiment> FIG. 5 is a schematic diagram showing a configuration of a resist reproducing system 200 according to a second embodiment of the present invention.

As shown in FIG. 5, the resist regenerating system 200 basically includes a resist regenerating system 10.
0 has the same configuration. Resist regeneration system 2
00 is in addition to the configuration of the resist regeneration system 100,
A solvent supply device 50 for adding a solvent to the thickened resist is provided. Then, the resist reproduction system 200
A thickening step similar to the thickening step performed in the resist regeneration system 100, after thickening the resist to a viscosity higher than the desired viscosity, and then adding a solvent to the resist to obtain a resist having a desired viscosity. This is a resist reproduction system that performs the following. Hereinafter, focusing on this difference,
The configuration and operation of the resist reproduction system 200 will be described. Note that the same components as those in the resist reproduction system 100 are denoted by the same reference numerals, and description thereof will be omitted.

The resist regenerating system 200 includes a solvent supply device 50 in addition to the components of the resist regenerating system 100.
It has. The solvent supply device 50 includes a solvent tank containing an organic solvent of the same component as the solvent of the resist, and a pump for sending the organic solvent contained in the solvent tank to the resist R in the regeneration container 12 through the pipe 52. Contains. The solvent supply device 50 is mechanically connected to the regeneration container 12 by a pipe 52. Further, the solvent supply device 50 is electrically connected to a control device 242 that controls the operation of the entire system of the resist regenerating system 200, and controls the organic solvent in the solvent tank in the regenerating container 12 under the control of the control device 242. It is configured to be added to R. The amount of the organic solvent added is determined by the control device 242.
Is calculated by

FIG. 6 is a block diagram showing a configuration of a main part of control device 242. As shown in FIG. 6, the control device 242 has substantially the same configuration as the control device 42 of the resist reproduction system 100. Control device 24
2 differs from the control device 42 in the configuration, for example, in that a solvent supply control unit 244 is provided. Further, the operation of the control device 242 is different from the control device 42 in that the addition amount w of the organic solvent is calculated based on the weight W3 of the resist after the thickening process, the viscosity η3, and the target viscosity η4. The point is that the supply device 50 is operated to perform an adjustment step of adding an organic solvent to the resist until the weight of the resist reaches the target weight W3 + w (W4) after the addition of the solvent. Hereinafter, the configuration of the control device 242 will be described focusing on the differences.

As shown in FIG.
Are a solvent supply controller 244 and a target weight calculator 246.
, A memory 248, and a thickening control unit 424.
Target weight calculation unit 246 and memory 248 of control device 242
The thickening control unit 424 is configured to function similarly to the target weight calculating unit 420, the memory 422, and the thickening control unit 424 of the control device 42 with respect to the thickening process.

The target weight calculating section 246 has the function of adding the weight w of the organic solvent to the resist after the thickening step to obtain the desired viscosity η4 in addition to the function of the target weight calculating section 420. Is provided. Also,
The memory 248 stores, in addition to the contents of the memory 422, data necessary for calculating the addition amount w of the organic solvent. Further, the solvent supply control unit 244 issues a solvent supply signal in response to an adjustment start command from the input device 44, and sends a solvent supply signal to the solvent supply device 50 until the resist weight becomes W3 + w, that is, the target weight W4 after the addition of the solvent. The organic solvent is added to the resist.

Next, the steps of regenerating the resist using the resist regenerating system 200 will be described. First, similarly to the resist regeneration system 100, a step of thickening the resist collected as a waste liquid is performed. However, in the resist regenerating system 200, the target viscosity η2 is set to be larger than the viscosity required for reusing the resist.

After the thickening step is completed and the temperature of the resist is lowered to about the same as room temperature, a resist adjusting step is performed. In the adjustment step, the resist is not heated. Therefore, during the adjustment process, the temperature of the resist is about room temperature. The adjustment process is also controlled by the control device 242.

The contents of the adjustment process performed under the control of the control device 242 will be described with reference to FIG. FIG. 7 is a flowchart illustrating the control performed by the control device 242 in the adjustment process.

When the thickening step is completed and the temperature of the resist is lowered to about the same as the room temperature, the weight W3 of the resist R in the regeneration container 12 is obtained from the weight sensor 24 to the control unit 24.
2 is input to the target weight calculation unit 246 (S21). Next, the viscosity η3 (cp) of the resist R in the regeneration container 12 measured by the operator and the target viscosity η4 (cp) of the resist in the adjustment process are input to the target weight calculation unit 246 via the input device 44. (S22). Here, W3 and η3 should theoretically be equal to the target weight W2 and the target viscosity η2 of the thickening step, but actually, W3, η3 are affected by the residual heat after the heating device 26 is stopped.
η2. Therefore, in the control in the adjusting step, the viscosity η3 and the weight W3 of the resist whose temperature has been lowered to room temperature after the thickening step is completed are used as initial values of the viscosity and the weight.

Next, the target weight calculator 246 calculates W3,
Based on η3 and η4 and the data in the memory 248, the target weight W4 after the addition of the solvent is calculated (S2
3), is sent to the solvent supply control unit 244. The target weight W4 after the addition of the solvent is determined when the weight w of the organic solvent is added to the resist R in the regeneration container 12 and the viscosity of the resist R in the regeneration container 12 reaches the target viscosity η4 during the adjustment process. Is the weight of the resist R, that is, W3 + w. A method for calculating the target weight W4 after the addition of the solvent will be described later.

When an adjustment start command is input via the input device 44, the solvent supply control section 244 issues a solvent supply signal (S24), activates the solvent supply device 50, and executes the adjustment process. (S25). In the adjusting step, the target weight W4 after addition of the solvent is set as a target value, and the weight W
Is performed while monitoring.

During the adjustment process, the solvent supply control section 244 compares the weight W of the resist R in the regeneration container 12 sent from the weight sensor 24 with W4 (S26).
As described above, during the adjustment step, the organic solvent is added to the resist R in the regeneration container 12 by the solvent supply device 50, so that the resist R in the regeneration container 12 has a viscosity η.
However, the weight W gradually increases and the weight W increases. While W is smaller than W4, the supply of the solvent is continued (S25). When the weight W of the resist R becomes equal to W4, the solvent supply control unit 244 determines that the resist R in the regeneration container 12 has been diluted to the target viscosity η4, and ends the adjustment process. (S27). That is, the operation of the solvent supply device 50 is stopped.

Thereafter, the second pump 34 is operated, and
The resist R in the reproduction container 12 is transferred to the reproduction resist container 14 via the pipe 32. On the way, the resist is filtered by the second filter 36 and further completely cooled by the cooling device 38. When all the resists have been transferred to the regenerated resist container 14, the regenerating process ends. In the resist regeneration system 200, the cooling device 38 or the operation thereof may be omitted.

In the resist reproducing system 200, the target weight W4 after the addition of the solvent to the resist is calculated in the target weight calculator 246 as follows. FIG. 8 is a graph showing the relationship between the viscosity of the resist used for this calculation (vertical axis) and the weight of the added organic solvent (horizontal axis).
The display unit of viscosity is cp, and the display unit of weight is g.

This graph is prepared in advance based on an experiment using a resist and a solvent of the same type as the resist to be regenerated. This graph shows that resists having different viscosities, for example, 5 cp, 6 cp, 7 cp, 8 cp, and 9 c
p, 10 cp of resist in a fixed amount (for example, 10 kg)
Calibration curves (g) to (l) were prepared by measuring the viscosity while adding an organic solvent to each, and plotting the relationship between the weight of the added organic solvent and the viscosity of the resist.
Is shown.

In the resist reproduction system 200, data corresponding to this graph is stored in the memory 24 of the control device 242.
8 is stored as a map (or table). When the viscosity η3 and the weight W3 of the resist after the thickening step and the target viscosity η4 are input, the target weight calculation unit 246 refers to the contents of the graph of FIG. And the weight w of the organic solvent to be added is calculated. Then, w is added to W3 to calculate a target weight (target weight after addition of the solvent) W4 of the resist in the adjustment step.

For example, according to the calibration curve (j) of this graph, in order to dilute a resist having a weight W3 of 10 kg and a viscosity η3 of 8 cp to a viscosity of 6 cp, which is a target viscosity η4 of the adjustment step, 400 g of an organic compound is required. It can be seen that a solvent may be added. Therefore, the weight w of the organic solvent to be added is 400 g, and W4 is calculated as W3 + 400 g.

Thus, the target weight W4 after the addition of the solvent is calculated based on the initial value W3 of the weight, the initial value η3 of the viscosity, and the target value η4 of the viscosity in the adjusting step. If the initial weight value W3 is not 10 kg,
By multiplying by an appropriate coefficient, the target weight W4 after the addition of the solvent is calculated.

According to the resist regenerating system 200 configured as described above, in the thickening step, an adjusting step of adding an organic solvent to a resist having a viscosity higher than the final target viscosity at room temperature is performed. Therefore, the viscosity of the resist can be adjusted with high accuracy.

Also in the resist reproduction system 200,
The method of calculating the target weight W4 after the addition of the solvent is not limited to the above-described calculation method, and may be another calculation method.

The present invention is not limited to the above embodiment, and various changes and modifications can be made within the scope of the items described in the claims. For example, the first
In the second and third embodiments, the resist regeneration system is separate from the resist coating device. However, the resist regeneration system of the present invention may be provided integrally with the resist coating device.

In the first and second embodiments, the solvent removing device of the resist regenerating system is a heating device,
A stirring device is provided. However, the solvent removing device of the present invention is not limited to this configuration, and any device capable of evaporating the solvent from the resist can be used.
Any configuration may be provided. For example, a configuration that includes a heating device and does not include a stirring device may be used.

[0108]

As described above, according to the present invention, the resist can be effectively used.

[Brief description of the drawings]

FIG. 1 is a drawing schematically showing a configuration of a resist reproduction system according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a main part of a control device of the resist reproduction system according to the first embodiment.

FIG. 3 is a flowchart showing the control performed by the control device in the thickening step by the control device of the resist regeneration system according to the first embodiment.

FIG. 4 is a graph showing the relationship between the viscosity and the weight of the resist used for calculating the target weight of the resist in the resist regeneration system according to the first embodiment.

FIG. 5 is a schematic diagram showing a configuration of a resist reproduction system according to a second embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of a main part of a control device of a resist reproduction system according to a second embodiment.

FIG. 7 is a flowchart illustrating the control performed by the control device in the adjustment process by the control device of the resist reproduction system according to the second embodiment.

FIG. 8 is a graph showing a relationship between the viscosity of a resist and the amount of an organic solvent used for calculating a target weight of a resist in an adjustment step in the resist regeneration system of the second embodiment.

[Explanation of symbols]

 10: Recovery Container 12: Regeneration Container 14: Regeneration Resist Container 16: Regeneration Chamber 18: Pipe Line 20: First Pump 22: First Filter 24: Weight Sensor 26: Heating Device 28: Stirring Device 28a: Stirring Member 28b: Drive Device 30: Temperature measurement device 32: Pipe line 34: Second pump 36: Second filter 38: Cooling device 40: Exhaust device 41: Nitrogen gas source 42: Control device 44: Input device 100: Resist regeneration system 420: Target weight Calculation unit 422: Memory 424: Thickening control unit

Claims (17)

[Claims] 1. A regenerating container for containing and regenerating a resist recovered from a resist coating device, a solvent removing device for evaporating a solvent component from the resist in the regenerating container to remove a part of the solvent component, A control device for controlling the operation of the removing device, wherein the control device operates the solvent removing device to remove the solvent component from the resist until the viscosity of the resist reaches a reusable target viscosity. A resist reproduction system, characterized in that: 2. The resist regenerating system according to claim 1, further comprising: a weight measuring device for measuring a weight of the resist in the regenerating container, wherein the control device is configured to determine the weight of the resist based on a measurement result of the weight measuring device. A resist regeneration system characterized by operating a solvent removing device. 3. The resist regeneration system according to claim 2, wherein the control device is configured to set a target weight of the resist after removing the solvent component based on a viscosity and a weight of the resist before removing the solvent component and a target viscosity of the resist. Wherein the solvent removal device is operated so that the weight of the resist becomes the target weight. 4. The resist regenerating system according to claim 1, wherein the solvent removing device includes a heating device for heating the resist in the regenerating container. Resist regeneration system. 5. The resist regenerating system according to claim 4, wherein the solvent removing device includes a stirring device for stirring the resist in the regenerating container. 6. The resist regenerating system according to claim 1, further comprising an exhaust device that accommodates the regenerating container in a closed regenerating chamber and exhausts the interior of the regenerating chamber. A resist reproduction system. 7. The resist regeneration system according to claim 6, further comprising a nitrogen gas source for supplying a nitrogen gas into the regeneration chamber. 8. The resist regeneration system according to claim 1, further comprising: a solvent supply device for adding a solvent to the resist in the regeneration container, wherein the control device is configured to supply the solvent with the solvent. Controlling the operation of the device, wherein the control device operates the solvent supply device so as to add a solvent to the resist from which the solvent component has been removed by the solvent removal device until the resist has a predetermined viscosity. Resist reproduction system. 9. The resist reproduction system according to claim 8, wherein the control device controls the operation of the solvent supply device based on a measurement result of the weighing device. 10. The resist regenerating system according to claim 9, wherein the control device is configured to control the post-addition of the solvent based on the viscosity and weight of the resist from which a part of the solvent component has been removed and the target viscosity after the addition of the solvent. A resist regeneration system, wherein a target weight is calculated and the solvent supply device is operated so that the weight of the resist becomes the target weight after the addition of the solvent. 11. A resist regenerating method for regenerating a resist recovered from a resist coating device, comprising: storing a resist recovered from the resist coating device in a regenerating container; evaporating a solvent component from the resist in the regenerating container; A method for regenerating a resist, comprising increasing the viscosity to a target viscosity that can be reused. 12. The method for regenerating a resist according to claim 11, wherein the evaporation of the solvent component is performed until the resist in the regeneration container reaches a target weight. 13. The method for regenerating a resist according to claim 12, wherein the target weight is calculated based on a viscosity and a weight of the resist before removing a solvent component and the target viscosity. . 14. The method for regenerating a resist according to claim 13, wherein the evaporation of the solvent component is performed while heating the resist in the regenerating container. 15. The resist regenerating method according to claim 14, wherein the evaporation of the solvent component is performed while stirring the resist in the regenerating container. 16. The method for regenerating a resist according to claim 14, wherein the regenerating container is housed in a closed regenerating chamber, and the evaporation of the solvent component supplies nitrogen gas into the regenerating chamber. And performing the process while evacuating the inside of the regeneration chamber. 17. The method for regenerating a resist according to claim 11, wherein a solvent is added to the resist having the increased viscosity.