JP5436028B2 - Resist solution recovery method - Google Patents

Description

  The present invention relates to a method for recovering a used resist solution, and more specifically, relates to a method for supplying a resist solution to a use facility equipped with a resist coating apparatus, and recovering the used resist solution after application and using it for recycling or the like. .

  In a manufacturing process of a semiconductor, a liquid crystal panel, etc., lithography is performed in which a resist solution is applied onto a substrate and exposed and developed. With the recent increase in size of liquid crystal panels and the like, the amount of resist solution used has also increased because the size of the substrate used has been increased. Typical coating methods include a spin coating method and a die coating (slit coating) method.

  In applying the resist solution to the substrate, an excessive amount of resist solution larger than the actual application amount is required, so that an excessive used resist solution is always generated. In particular, when using spin coating, the amount of used resist solution is not negligible. Therefore, it is economically and environmentally desirable to recover and recycle it as an effective use.

  With respect to such recovery and recycling of the resist solution, recovery devices such as those in Patent Documents 1 and 2 below are known. In this system, a recovery / regeneration device is attached to the resist solution coating apparatus itself, and the resist solution is recycled by adjusting the viscosity or filtering the filter.

  In addition to this, a common large collection line is installed in a facility equipped with a plurality of resist solution coating devices, and used resist solutions from a plurality of coating devices are collectively collected in a tank or the like. It is also sent back to the manufacturer and recycled by the resist manufacturer.

  On the other hand, a resist solution is usually supplied from a resist manufacturer to users such as semiconductor manufacturers and liquid crystal panel manufacturers. In this case, for example, a small dedicated container having a predetermined capacity as described in Patent Document 3 is used. This dedicated container has a double structure of a small rigid container and an inner bag made of a flexible material that can be attached and detached. Such a dedicated container has become mainstream because it can be directly connected to a user's line as it is, is easy to handle, and has a low risk of contamination of the resist solution. This dedicated container is delivered to the user with the inner bag filled with the resist solution, used by the user directly connected to the line of the coating device, etc., and used as it is after being used (the inner bag is an empty bag). After being collected and returned to a resist manufacturer or the like, cleaned, etc., the resist solution is filled again and used as a so-called return container.

JP-A-9-34121 JP-A-11-245226 Japanese Patent Laid-Open No. 6-100087

  The resist solution recovery systems such as Patent Documents 1 and 2 are basically intended for recycling on the user side. In this case, it is necessary for the user to perform quality control of the recycled resist solution, and it is difficult for the user who is not familiar with the resist solution to stably perform the above quality control.

  Also, the method of collecting the used resist solution from multiple coating devices in a tank etc. and returning it to the resist solution maker requires the installation of a collection facility on the user side. Burden is newly generated.

  In addition, the dedicated container of Patent Document 3 is only a resist solution supply container, and it is not assumed that the used resist solution is refilled after the pumping is finished. Can not.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have conventionally used a pail can used as a resist solution supply container as a resist solution recovery container as a supply and recovery container. By using it, it discovered that said problem could be solved, and came to complete this invention.

  That is, the present invention supplies a resist solution from a resist solution supply facility to a resist solution use facility using a dedicated container having a predetermined capacity, and collects the used resist solution at the resist solution use facility using the dedicated container. A resist solution recovery method that is also used as a resist solution recovery container of the above, and as the dedicated container, a cylindrical synthetic resin inner container and a metal outer container constituting the outer shell of the inner container And a resist solution recovery method using a pail can.

  A feature of the present invention is that a pail can which has been conventionally used as a resist solution supply container is used as a supply and recovery container. In this respect, the present invention provides a new method for recovering a resist solution, and can be said to have found a new use for recovery in a conventional supply-only container.

  According to the present invention, an existing resist solution supply system using a pail can can be used as it is. Therefore, it is not necessary for the user to provide special recovery equipment or recycling equipment. For this reason, the degree of freedom of equipment on the user side is high. Specifically, the present invention can be effectively used when the resist solution recovery equipment cannot be installed in a space due to the line arrangement of the existing resist solution coating apparatus.

  In addition, because it can be recovered using the existing resist solution supply system as it is, compared to the conventional method of collecting the used resist solution from a plurality of coating devices in a tank and returning it to the resist solution manufacturer, Collection costs and labor can be greatly reduced.

  In the present invention, the meaning of “use a dedicated container as a resist solution recovery container” in the present invention means that the dedicated container is sufficient if it can be used for both supply and recovery. For this reason, it is not required that the supply operation and the recovery operation are close in time. That is, if the exclusive container used for supply is used as a collection container after that, it is within the scope of the present invention. In addition, even if the type and capacity of the supply container is different from that of the collection container when viewed in units of resist solution coating equipment, the supply container will eventually be somewhere in the resist solution use facility. If it is used as a recovery container, it is still within the scope of the present invention.

  According to the present invention, the resist solution can be efficiently recovered at a lower cost by using a pail can as the dedicated container.

It is process drawing which shows an example of this invention. It is a perspective appearance figure showing one embodiment of a pail can in the present invention. It is a front view which shows one Embodiment of the dispenser connected to a pail can, and has shown the principal part in the cross section. FIG. 2 is a state diagram in which a dispenser is connected to a pail can, and the dispenser is an exploded view. It is a perspective appearance figure of a pail, and shows a pail can for resist liquid of a top plate removable type. It is a perspective appearance figure of a pail, and shows a pail can for resist liquid of a top plate removable lug type. FIG. 2 is a perspective external view of a pail can, showing a T-type resist solution pail that is provided with a damage protection body on the periphery of the top plate and the periphery of the base plate, and the body is tapered. FIG. 2 is a perspective external view of a pail can, showing an S-type resist pail can provided with a damage protection body on the periphery of the top plate and the periphery of the base plate and having a trunk formed straight. It is the schematic which shows an example of a resist liquid collection | recovery system.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

<Pail can>
First, a pail can (dedicated container) 10 that serves as a supply and recovery container in the present invention will be described. In FIG. 2, the pail can 10 includes an inner container 1 made of synthetic resin and an outer container 2 made of metal. The inner container 1 is formed in a cylindrical shape. The outer container 2 constitutes the outer shell of the inner container 1. The inner container 1 has a mouth portion 11 that opens so that a resist solution can be injected.

  In FIG. 2, the outer container 2 has a top plate 21, a body 22, and a ground plate 23. The top plate 21 has a hole 2a from which the mouth portion 11 protrudes. The body 22 surrounds the outer periphery of the inner container 1. The ground plane 23 is in contact with the bottom surface of the inner container 1.

  The inner container 1 shown in FIG. 2 is formed in a conical trapezoidal shape in which the area of the upper surface is larger than the area of the bottom surface. The inner container 1 is formed of a synthetic resin, preferably a polyolefin such as polyethylene (PE) or polypropylene (PP).

  In FIG. 2, the outer container 2 is made of a metal plate so as to cover the inner container 1, and constitutes an outer shell of the inner container 1. The outer container 2 is not necessarily in contact with the entire outer periphery of the inner container 1. In FIG. 5 or FIG. 6, the body 22 surrounding the outer periphery of the inner container 1 (not shown) is provided with an annular zone 22a to increase the mechanical strength of the outer container 2 itself. The annular zone 22 a is partially separated from the inner container 1.

  In FIG. 2, the top plate 21 is provided with a plurality of annular zones 21a concentrically so as to increase the mechanical strength of the outer container 2 itself. The annular zone 21 a is in partial contact with the inner container 1. Further, an annular step 21b is provided around the hole 2a, and is reinforced so that tensile stress concentrates on the hole 2a and no crack is generated (see FIG. 3).

  In FIG. 2, the external thread 11a is formed in the outer periphery of the opening | mouth part 11 (refer FIG. 3). The pail can 10 is sealed by sealing the opening of the mouth 11 with a cap 31 and screwing the mouth 11 with a lid 32. And it can convey without spilling a resist liquid.

  The outer container 2 shown in FIG. 2 is a so-called top plate fixing type pail in which a flat steel plate is formed in a cylindrical shape to produce a body 22, and the top plate 21 and the base plate 23 are fixed to the body by winding. It is a can. Further, the outer container 2 shown in FIG. 2 includes a suspension 24 on the top plate 21. The mounting bracket 24a that rotatably supports the suspension 24 is joined to the top plate 21 by spot welding. The suspension 24 is disposed at the approximate center of the top plate 21.

  The outer container 2 shown in FIG. 5 is a so-called top plate detachable band type in which a flat steel plate is formed into a cylindrical shape to produce a body 22, and a top plate 21 is fastened to the body 22 by a band 2b. It is a pail can. Further, the outer container 2 shown in FIG. 5 includes a pair of ears 25a and 25b provided on the top plate 21 side of the body 22 and a vine handle 25 rotatably connected to the pair of ears 25a and 25b. And. And the attachment metal fitting used as a pair of ear 25a * 25b is joined to the top plate 21 side of the fuselage | body 22 by spot welding.

  The outer container 2 shown in FIG. 6 has a plurality of claws 2 c on the periphery of the top plate 21. Then, a plate-shaped steel plate is formed into a cylindrical shape, and the body 22 is manufactured. The top plate 21 is tightened to the body 22 by a plurality of claws 2c. . Further, the outer container 2 shown in FIG. 6 includes a pair of ears 25a and 25b provided on the top plate 21 side of the body 22 and a vine handle 25 rotatably connected to the pair of ears 25a and 25b. And. And the attachment metal fitting used as a pair of ear 25a * 25b is joined to the top plate 21 side of the fuselage | body 22 by spot welding.

  As shown in FIG. 2 or FIG. 7, the body 22 may be formed in a conical trapezoidal shape in which the area on the top plate 21 side is larger than the area on the ground plate 23 side, and as shown in FIG. May be formed in a right cylindrical shape (see FIGS. 5 and 6).

  Further, as shown in FIGS. 7 and 8, by providing the damage protectors 26 on both the periphery of the top plate 21 and the periphery of the base plate 23, damage to the pail can 10 during transfer can be prevented. For example, the damage protector 26 is a bendable synthetic resin band that forms a groove in the longitudinal direction, and is attached by fitting the groove to the periphery of the top plate 21 and the periphery of the base plate 23. In the case of the conical pail 10 shown in FIG. 7, the damage protector 26 may be provided only on the top plate 21 side. When the conical pail cans 10 are arranged side by side in the vertical and horizontal directions, damage around the top plate 21 can be prevented.

In the pail can 10 according to the present invention, the inner container 1 is pressurized with a compressed fluid such as nitrogen, and the resist solution is discharged. The outer container 2 has rigidity so as to prevent deformation of the inner container 1 against the internal pressure applied to the inner container 1. Having rigidity may include that the outer container 2 is formed of a rigid metal plate, and the outer container 2 has a mechanical structure so that the inner container 1 does not deform due to expansion or the like. Can be included. For example, the pail can 10 shown in FIG. 2 is a pail can with a rated capacity of 20 liters and a proof stress of 0.5 kgf / cm ² .

  The pail can according to the present invention is a pail can whose outer container is formed from a thin steel plate, and is lighter than a canister can formed from a thick steel plate. In addition, there is an advantage that it is easy to manufacture and can be manufactured at low cost. Further, the pail can according to the present invention is not configured to be transported with a coupling with a liquid discharge tube, and is configured to include a liquid discharge tube on the dispenser side, thereby reducing the manufacturing cost of the container. It is also possible. In addition, there is a merit that the trouble of cleaning the liquid discharge tube and the trouble of refilling the bag into the outer container can be saved, and it is economical in general as compared with the double storage type resist solution container.

  Further, the inner wall of the metal can is not coated with a synthetic resin film, and the outer container made of metal constitutes the outer shell of the inner container made of synthetic resin. Such a double pail can easily separates and disassembles the metal and the synthetic resin, and can help to recycle resources.

<Resist liquid filling step S10>
Hereinafter, an example of the present invention using the above-described pail can 10 will be described with reference to the process diagram shown in FIG. First, the resist solution manufactured in the resist solution supply facility 100 of a resist manufacturer or the like is filled in the pail can 10 with the resist solution filling step S10. The resist solution supply facility 100 only needs to be able to fill a dedicated container, and does not necessarily require a resist solution manufacturing facility. That is, the resist solution supply facility 100 is a concept including a relay base for supplying the resist solution to the user.

  First, in the state of FIG. 2, the inner container 1 is preferably expanded by introducing nitrogen or compressed air from the mouth portion 11 in advance. Next, a filling tube (not shown) for filling the resist solution is inserted into the mouth portion 11, and a predetermined amount of the resist solution is filled through the filling tube. As a result, the resist solution can be filled in a sealed system without contamination. At this time, a dispenser 40 described later may be used.

  Thereafter, the opening of the mouth portion 11 is sealed with the cap 31, and the mouth portion 11 is screwed with the lid 32, whereby the pail can 10 is sealed. And it can convey without spilling a resist liquid.

<Resist Solution Supply Step S20>
Next, the pail 10 is transported from the resist solution supply facility 100 to the resist solution use facility 200 on the user side. The resist solution use facility 200 includes one or a plurality of resist solution coating apparatuses such as a spin coater and a slit coater, and the pail can 10 is substantially sealed with respect to each resist solution coating apparatus via a dispenser. The system is connected to the supply pipe, and the resist solution is supplied. The supply joint is not particularly limited as long as it can maintain a closed system, and a conventionally known one can be used.

  Specifically, as shown in FIG. 3 or FIG. 4, the dispenser 40 can be easily attached and detached using the mouth portion 11 provided with the external thread 11 a on the outer periphery. The dispenser 40 includes a cylindrical plug body 41, a venting means 42 that can ventilate a compressed fluid into the inner container, and a liquid discharge pipe 43.

  In FIG. 3 or FIG. 4, the plug main body 41 has a seal ring 41 a having an open central portion so as to be freely movable, and the mouth 11 can be sealed by fastening the plug main body 41 to the mouth 11. The ventilation means 42 includes an elbow-shaped (L-shaped) joint 42 a and an opening 42 b penetrating from the outside of the plug body 41 toward the mouth. By connecting the joint 42a to the opening 42b, the compressed fluid can be vented to the inside of the inner container 1. One end of the liquid discharge pipe 43 reaches the bottom surface of the inner container 1, the other end projects from the plug body 41, and is attached to the plug body 41 so as to be sealed. Then, the resist liquid can be distributed from the liquid discharge pipe 43 by pressurizing a compressed fluid such as nitrogen into the inner container 1 from the aeration means 42. As a result, the resist solution can be filled in a sealed system without contamination. As another ventilation means (not shown), the distribution of the resist solution may be facilitated by sending a compressed fluid between the inner container 1 and the outer container 2.

  In this way, when the resist solution is used, that is, when the resist solution is pumped out, it can be pumped out from the mouth portion 11 through the liquid discharge pipe 43. As a result, the resist solution in the inner container 1 is pumped to become a used container that is almost empty.

<Resist Solution Recovery Step S30>
A feature of the present invention is that the pail can 10 (used container) after the resist solution is pumped out is not returned to the resist maker as it is, but is used again in the resist solution recovery step. That is, the used container is later used as a recovery container in the resist solution recovery step S30. The later interval is set as appropriate depending on the number of used containers and the operation status of the resist coating apparatus. That is, in FIG. 1, the resist solution recovery step S30 has been described following the resist solution supply step S20 for the sake of convenience. However, in an actual resist solution coating apparatus, S20 and S30 proceed simultaneously in parallel. The used container generated in the liquid supply step S20 is used in the current resist solution recovery step S30. The collection work will be described below.

  An example of the resist solution recovery system shown in FIG. 9 recovers a used resist solution 252 generated by a spin coater 250 which is an example of a resist coating apparatus and a recovery pan 251 provided around the rotating portion of the spin coater 250. The recovery pipe 253 for carrying out, the recovery pump 254 provided in the recovery pipe 253, the pail 10 which is the above-mentioned used container connected to the tip of the recovery pipe 253, and a branch from the middle of the recovery pipe 253 The switching valve 259, a piping 255 extending from the switching valve 259 and a recovery pipe 253, and a cleaning liquid recovery tank 256 connected to the tip of the pipe 255.

  First, a collection tube (not shown) for collecting the resist solution is attached to the mouth portion 11 of the pail can 10 that is a used container, for example, via the dispenser 40 described above. The recovery pipe 253 is connected in a closed system through the recovery tube.

  When the spin coater 250 is operated, a resist solution is applied from the application portion 258 on the substrate 257. This resist solution diffuses to the surroundings by centrifugal force, and excess used resist solution 252 is stored in the recovery pan 251. Here, by operating the recovery pump 254, the used resist solution 252 is recovered in the pail can 10 through the recovery pipe 253. That is, the used resist solution 252 is refilled in the inner container 1 of the pail can 10.

  Note that, as described above, the inside of the inner container 1 at the start of the collection operation may be shrunk due to passing through the pumping process in the resist solution supply process S20, and the capacity recovery of the bag only by refilling is insufficient. There is a case. For this reason, the refillable capacity (recoverable capacity) at this time is smaller than that in the resist solution supply step S20 in which the inner container 1 is previously expanded with nitrogen or air. However, since the amount of used resist solution that can be collected is reduced by the amount actually applied, the amount of used resist solution that matches the amount of resist supplied to the coating device is sufficient in a dedicated container of the same capacity. Can be recovered.

  The switching valve 259 and the cleaning liquid recovery tank 256 are for cleaning the recovery pipe 253 with thinner or the like, and send the recovery liquid to the cleaning liquid recovery tank 256 side while a predetermined cleaning operation is performed. Thereby, contamination other than the resist solution to the pail can 10 can be effectively prevented.

  After a predetermined amount of collection is completed, the collection tube and the dispenser 40 are removed from the pail can 10, the opening of the mouth portion 11 is sealed with the cap 31, and the mouth portion 11 is screwed with the lid 32. 10 is sealed. This is returned to the resist solution supply facility 100 such as a resist manufacturer. Thereby, the pail can 10 functions as a supply and collection container and contributes to the improvement of the collection efficiency. In addition, it is preferable that said resist liquid collection | recovery process S30 is performed per resist liquid coating device unit similarly to resist liquid supply process S20.

<Composition confirmation process S40>
The refilled pail can 10 is returned to the resist solution supply facility 100, and the composition confirmation step S40 is performed at the receiving stage. This step is a step of confirming the composition and type of resist for each dedicated container in order to avoid contamination of various resists sent from a plurality of different resist solution use facilities 200. Although the confirmation method is not particularly limited, an example is a method of measuring the concentration or type using infrared or near infrared spectroscopy.

<Recycling process S50>
Thereafter, the used resist solution is pumped out by the same method as in the resist solution supply step S20, and the resist solution is recycled in the recycling step S50. A conventionally known recycling method can be used and is not particularly limited. In addition, the inner container 1 is removed from the pail can 10 after the completion of the pumping and discarded. The outer container 2 may be discarded at this stage, or a new inner container 1 may be attached and reused.

  As described above, according to the present invention, the resist solution can be collected lightly and inexpensively using the pail can, and the collection cost can be reduced and the recycling rate of the resist solution can be increased.

1 inner container 2 outer container 2a hole 10 pail can (dedicated container)
11 mouth part 21 top plate 22 body 23 ground plate 100 resist solution supply facility 200 resist solution use facility 250 spin coater S10 resist solution filling step S20 resist solution supply step S30 resist solution recovery step S40 composition confirmation step S50 recycling step

Claims (5)

While supplying a resist solution from a resist solution supply facility to a resist solution use facility using a dedicated container of a predetermined capacity,
This dedicated container is a resist solution recovery method that is also used as a resist solution recovery container for recovering a used resist solution in the resist solution use facility,
As the dedicated container, a pail can including a cylindrical inner container made of a synthetic resin and a metal outer container constituting the outer shell of the inner container is used,
The resist solution use facility is a facility including a resist solution coating apparatus, and the resist solution supply operation from the inner container filled with the resist solution to the resist solution coating apparatus, and substantially from the resist solution coating apparatus. The recovery operation of refilling the used resist solution into the inner container after the supply operation, which is an empty bag, is performed in a substantially sealed system,
A resist solution recovery method in which the resist solution recovery container is returned to the resist solution supply facility after the recovery, and the used resist solution is pumped out of the inner container and recycled at the resist solution supply facility . The inner container has a mouth opening so that a resist solution can be injected,
The outer container has a top plate having a hole through which the mouth projects, a body that surrounds the outer periphery of the inner container, and a ground plate that contacts the bottom surface of the inner container,
The resist solution recovery method according to claim 1, wherein the outer container has rigidity so as to prevent deformation of the inner container against an internal pressure applied to the inner container.   The resist solution recovery method according to claim 1, wherein the top plate and the ground plate are fixed to the body by winding.   The resist solution recovery method according to claim 1, wherein the top plate is fastened to the body by a band. The resist solution recovery method according to claim 1, wherein the supply operation and the recovery operation are performed in units of the resist solution application apparatus.

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