JP2593294B2 - Resist coating apparatus and resist coating method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist coating apparatus and a resist coating method, and more particularly to a resist coating apparatus and a resist coating method for evacuating air during the supply of the resist solution.

[0002]

2. Description of the Related Art An example of this type of coating apparatus is a coating apparatus for coating a resist on a wafer in a semiconductor manufacturing apparatus. When applying a resist on a wafer, the wafer is mounted and fixed on a rotatable spin head placed inside the processing vessel, and a resist solution is supplied to the wafer surface through a nozzle while rotating the wafer to apply the resist. Processing (JP-B-53-37189).

Here, if air is mixed in the middle of the resist solution supply path, the resist is dried and its components are changed, or if air is mixed between the resist discharge pump and the nozzle, it is dropped. Fluid volume changes,
Since the application unevenness of the resist occurs, it is necessary to remove this in the course of the resist solution supply path.

Therefore, a trap 101 containing a filter 100 for removing dust therein is provided in the middle of the supply of the resist solution to the nozzle as shown in FIG. The discharge pipe 102
Is to be removed through.

When air is evacuated from the trap 101 in the conventional apparatus, the exhaust pipe 102 is evacuated by a vacuum pump. The vacuum pump is driven and a valve provided in the exhaust pipe 102 is provided. 103 was manually opened and closed.

[0006]

According to the above-described conventional apparatus, when air is removed from the resist solution supply path,
Since the operation was performed manually, the operation was extremely complicated.

In particular, in this type of resist coating apparatus, there are some types that use about three types of resist liquids. In this case, each of the resist coating apparatuses has a resist liquid supply system. Manual bleeding work is required.

[0008] Here, the frequency of air bleeding of the resist solution varies depending on the manufacturer and the like.
There are various things, such as once every three days or once a week. When manually executed, it is necessary to also perform schedule management of air bleeding, etc. In addition, there has been a problem that the resist coating operation is hindered.

Therefore, an object of the present invention is to solve the above-mentioned conventional problems and to perform the air bleeding operation in the middle of the resist solution supply path automatically at appropriate intervals, thereby greatly reducing the air bleeding work. Another object of the present invention is to provide a resist coating apparatus and a resist coating method which can be simplified.

[0010]

According to a first aspect of the present invention, there is provided a resist coating apparatus for dropping and coating a resist solution on a surface of a material to be coated, wherein the resist solution is disposed in a resist solution supply path. A trap container, an air discharging means for sucking and discharging air trapped in the upper portion of the trap container, and an interval time for discharging the air trapped in the trap container at predetermined time intervals. First determining means for determining whether or not processing has been performed, and second determining means for determining whether or not the processing of one lot of the material to be coated is completed and before the start of processing of the next lot. The first determining means determines that the set interval time has elapsed, and the second determining means
Is determined to be a lot break,
Control means for driving the air discharge means to automatically control the air discharge operation.

According to a second aspect of the present invention, in the first aspect, there is provided a resist nozzle for dropping a resist solution onto the surface of the material to be coated, and a resist discharge pump for supplying the resist solution to the resist nozzle, The trap container is provided in the middle of a resist liquid supply path from the resist discharge pump to a resist nozzle.

According to a third aspect of the present invention, in the second aspect, the resist solution supplied to the trap container is supplied to the resist nozzle via a filter.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the trap container has a resist liquid introduction hole and an air discharge hole, and the resist liquid introduction hole is connected to the air discharge hole. It is characterized in that it is arranged at a lower position than that.

According to a fifth aspect of the present invention, in the fourth aspect, the trap container has a wall portion located between the resist solution introduction hole and the air discharge hole, wherein the wall portion is formed from the resist solution introduction hole side. It is characterized by being inclined toward the discharge hole side.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the air discharge means includes a vacuum pump for sucking air accumulated in an upper portion of the trap container, and the trap container and the vacuum pump. And an air vent valve disposed between the vacuum pump and the air vent valve. A waste liquid trap is disposed between the vacuum pump and the air vent valve.

According to a seventh aspect of the present invention, there is provided a resist coating method in which a resist liquid is dropped onto a surface of a material to be coated from a resist nozzle via a trap container provided in the middle of a resist liquid supply path. A step of presetting an interval time for discharging the air accumulated in the container every predetermined time, determining whether or not this interval time has elapsed, and processing one lot of the material to be coated is completed;
A step of determining whether or not the lot is a break before the start of processing of the next lot; and a step of automatically discharging air trapped in the trap container at the break of the lot after the interval time has elapsed. And characterized in that:

According to an eighth aspect of the present invention, in the seventh aspect, the resist solution is contained in the trap container while the resist solution is supplied from the resist discharge pump to the resist nozzle in the resist solution supply path. A resist solution is supplied from the trap container to the resist nozzle.

According to a ninth aspect of the present invention, in the seventh or eighth aspect, the resist solution supplied to the trap container is supplied to a resist nozzle via a filter.

According to a tenth aspect of the present invention, in the step of discharging the air in the trap container, the air in the trap container is suctioned, and the resist solution sucked together with the air is stored in a waste liquid trap and discharged. It is characterized by.

[0020]

According to the first aspect of the present invention, when the air accumulated in the upper portion of the trap container is discharged by driving the air discharging means, when a set interval time has passed and a lot break has occurred, The air bleeding operation can be automatically performed, the air bleeding operation can be reliably performed, and the burden on the operator can be greatly reduced.

Moreover, since the air bleeding operation is performed at a break between lots where the resist coating operation has not been performed,
The air can be efficiently removed without interrupting the application operation in the middle of the lot, and the yield can be improved.

According to the second aspect of the present invention, air is often mixed into the resist solution when the resist discharge pump is driven, and such a trap is disposed at the subsequent stage of the pump. Air can also be eliminated.

According to the third aspect of the present invention, dust and the like can be removed by a filter from the resist solution in a state where air is not mixed by the trap container, so that a more favorable resist solution can be supplied. be able to.

According to the fourth aspect of the invention, when air is mixed in the resist solution, the air having a low specific gravity rises, and the air discharge hole side located at a position higher than the resist solution introduction hole. The air can be stored easily.

According to the fifth aspect of the present invention, by inclining the wall as described above, the air can be reliably stored near the air discharge hole.

According to the sixth aspect of the present invention, when air in the trap container is sucked by the vacuum pump, the resist solution in the trap container which is sucked at the same time is accommodated in the waste liquid trap and discharged. be able to.

According to the present invention, when the air accumulated in the upper portion of the trap container is discharged, the air bleeding operation is automatically performed when a set interval time has passed and the lot is at a break. Can be performed, the air bleeding operation can be performed reliably, the burden on the operator can be greatly reduced, and the air bleeding operation is performed at a break between lots where the resist coating operation has not been performed. The air can be efficiently removed without interrupting the application operation in the middle of the lot, and the yield can be improved.

In the invention according to claim 8, air is often mixed into the resist solution when the resist discharge pump is driven, and such air can be reliably removed by the trap container. .

According to the ninth aspect of the present invention, dust and the like can be removed by a filter from the resist solution in a state where air is not mixed by the trap container, so that a more favorable resist solution can be supplied. be able to.

According to the tenth aspect of the invention, when the air in the trap container is sucked, the resist solution in the trap container which is sucked at the same time can be stored in the waste liquid trap and discharged. .

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a resist coating apparatus for a semiconductor wafer will be specifically described with reference to the drawings.

First, the outline of the resist coating apparatus will be described.
This will be described with reference to FIG.

The spin chuck 10 is capable of mounting and fixing the semiconductor wafer 1 by, for example, vacuum suction and rotating the same.
, And is driven to rotate.

The motor 20 is composed of a high-performance motor having excellent acceleration characteristics, and has a flange 21 on the upper side thereof, and is fixed at an appropriate position in the coating apparatus by the flange 21. The temperature of the flange 21 can be adjusted by a temperature controller (not shown), and the flange 21 may be configured not to transmit the heat generated by the motor 20 to the upper side.

Above the wafer 1 supported by the spin chuck 10, there is provided a resist nozzle 30 for dropping a resist liquid from a substantially central position of the wafer 1, and the resist nozzle 30 is movable by a scanner 31. I have.

For example, when the nozzle 30
If the dispensing from is not performed for a predetermined time,
When the resist liquid is in contact with air for a long time at the tip of the resist nozzle 30, the resist liquid may harden,
Need to perform dummy dispense.

In this case, it is necessary to retreat the resist nozzle 30 to a position where the resist nozzle 30 has been removed from the chuck 10.
This kind of movement is executed by the scanner 31.

It should be noted that a plurality of resist nozzles 30 of this type may be provided and used properly according to the type of resist liquid.

Further, a cup 40 as a processing container is formed around the semiconductor wafer 1 in order to prevent the resist solution from scattering outside the apparatus when the resist solution is applied.

The cup 40 can be moved up and down so that it rises to the position shown in FIG. 2 when the resist solution is applied and stops, and lowers when the semiconductor wafer 1 is loaded and unloaded. Have been.

A drain pipe and an exhaust pipe (not shown) are connected to the lower surface of the cup 40.

A cleaning nozzle 50 for cleaning the back surface of the semiconductor wafer 1 is fixed to a mounting flange 21 of the motor 20 which is disposed at a position facing the back surface of the semiconductor wafer 1.

The cleaning nozzle 50 needs to be fixed at least at a position off the chuck 10.

The cleaning nozzle 50 is provided with a solvent storage section 51 for supplying a cleaning liquid, for example, a solvent. The solvent can be discharged to the back surface of the semiconductor wafer 1 via the cleaning nozzle 50.

Next, a system for supplying the resist liquid to the resist nozzle 30 will be described.

The supply system includes a resist solution storage unit 3
2, a bellows pump 33, a filter container 34 which is an example of a trap container, a valve V1 and a suck-back valve V2 which are opened and closed in conjunction with the bellows pump 33 are provided.

The suck back valve V2 is a valve for returning the resist liquid exposed by the surface tension at the tip of the resist nozzle 30 to the inside of the resist nozzle 30 after the resist liquid is discharged from the resist nozzle 30. This is to prevent the solidification of the resist solution.

The bellows pump 33 includes a cylinder 33
a, a check valve 33b and a bellows part 33c, a resist liquid introduction pipe is connected between the check valve 33b and the cylinder 33a, and the resist liquid can be drawn out from the upper end of the bellows part 33c. .

The cylinder 33a has ports 33e and 33f for introducing air above and below the partition plate 33d, and can perform a pump operation by moving the partition plate 33d up and down.

Next, the structure of the air discharging means for bleeding the resist solution from the filter container 34 will be described with reference to FIG.

The filter container 34 has an upper wall 34c connecting the resist solution introducing pipe 34a so that the side to which the resist liquid introducing pipe 34a is connected is disposed on the lower side and the side to which the air discharge pipe 60 is connected is disposed on the upper side. The filter 34b is arranged in the inside, and the resist solution that has passed through the filter 34b can be led out from the lower end.

In the middle of the air discharge pipe 60, for example, an air vent valve 61 which can be opened and closed by solenoid driving is provided, and a waste liquid trap 62 is provided on the subsequent stage.

At the lower end of the waste liquid trap 62, there is provided a waste liquid valve 63 which is also opened and closed by driving a solenoid or the like. On the other hand, a vacuum pipe 64 is connected to the upper end of the waste liquid trap 62, and air is evacuated by a vacuum pump 65. It is possible.

Next, a control system for controlling the air bleeding operation will be described with reference to FIG.

The CPU 70 controls the apparatus of this embodiment. In particular, the CPU 70 controls the opening and closing of the air release valve 61 and the waste liquid valve 63 and the drive control of the vacuum pump 65 to control the above-described air release operation. Is executable.

The CPU 70 has a time setting section 7 for setting an interval time for repeatedly performing the air bleeding operation at predetermined time intervals according to the type of the resist solution.
1 is connected, and when there are a plurality of resist liquid supply systems, time can be set for each supply system.

Further, before the semiconductor wafer 1 is loaded into the coating apparatus, a loading ready signal which is output when the semiconductor wafer 1 is present in the preceding transport unit is input to the CPU 70. I have.

The CPU 70 is connected to a counter 72 which counts down the set time after the air bleeding operation is completed. The CPU 70 is set to the air bleed ready state after the lapse of the set time, and is located at a break between lots to which the transport ready signal is not inputted. Then, the valves 61 and 63 are driven and the vacuum pump 65 is driven to execute and control the air release operation.

In this sense, the time setting section 71 and the counter 72 constitute a first judging means of the present invention for judging whether or not the interval time has elapsed, and the CPU 70 judges whether or not a lot break has occurred. Thus, the control means of the present invention for automatically controlling the air discharging operation by driving the second judging means and the air discharging means of the present invention.

Next, the resist coating method will be described together with the operation of the resist coating apparatus.

First, in a normal resist coating step, after the CPU 70 receives a transfer ready signal from the transfer section, it detects that the semiconductor wafer 1 is no longer present on the spin chuck 10 by a vacuum check of the spin chuck 10 or the like. When the absence of the wafer 1 is confirmed, the semiconductor wafer 1 is carried into a coating apparatus and placed on the spin chuck 10.

Next, the vacuum system of the spin chuck 10 is driven to fix the semiconductor wafer 1 on the spin chuck 10 by vacuum suction.

Thereafter, the cup 40 is raised and stopped at the position shown in FIG.

The above-described transport drive is executed according to a transport program incorporated in advance based on a command from the CPU 70 of the resist coating apparatus.

After the completion of the transport drive, the original program incorporated by the user is transferred to a recipe (Recipe).
The resist application operation is started by being executed by a controller (not shown).

That is, while the semiconductor wafer 1 on the spin chuck 10 is rotated at about 1000 rpm by the drive of the motor 20, the valves V1 and V2 are opened and the bellows pump 33 is driven, so that the semiconductor wafer 1 A predetermined amount of resist liquid is dropped on the surface of the semiconductor wafer 1 from a resist nozzle 33 set at an upper position located at the center.

Thereafter, the number of rotations of the semiconductor wafer 1 is increased to 400
The wafer is rotated up to about 0 rpm, and the resist liquid is uniformly applied to the surface of the semiconductor wafer 1 by centrifugal force.

At this time, the resist liquid scattered from the end of the semiconductor wafer 1 is guided to the bottom by the cup 40 and is discharged from a drain tube (not shown).

After the completion of the resist coating operation, the back surface cleaning of the semiconductor wafer 1 contaminated by the operation is started.

This back surface cleaning is performed while a cleaning agent such as a solvent is discharged from the cleaning nozzle 50 and the semiconductor wafer 1 is rotated by the motor 20 at a rotation speed of, for example, about 2000 rpm.

After the back surface cleaning of the semiconductor wafer 1 is completed, the cup 40 is lowered below the position shown in FIG.
Next, after turning off the vacuum of the spin chuck 10, the unloading of the semiconductor wafer 1 is executed.

By the above operation, one semiconductor wafer 1
, One cycle of the resist application operation is completed, and thereafter, this operation is repeatedly executed.

Here, in this type of resist coating apparatus,
There is a demand to apply the resist liquid uniformly on the semiconductor wafer 1. For this purpose, it is necessary to discharge an appropriate amount of the resist liquid from the nozzle 30.

If air is mixed in the resist supply system, the proper discharge operation cannot be secured.
Further, there is also a problem that the resist solution dries when it comes into contact with air, and its components change.

Therefore, the CPU 70 automatically controls the air bleeding operation in the resist supply system.

That is, an interval time for repeatedly executing the air bleeding operation is set in advance by the time setting unit 71.

Then, the set time is counted down by the counter 72.

When the CPU 70 detects from the output of the counter 72 that the set time has elapsed, the CPU 70 sets the air bleed ready state, and then checks whether or not a transport ready signal from the transport section is input.

The air release operation is controlled to start only when the transport ready signal is, for example, a break between lots interrupted for a predetermined time.

As described above, the reason why the air bleeding operation is performed at a break between lots is that the resist coating operation cannot be performed in parallel during the air bleeding operation. This is because it is necessary to interrupt the resist coating operation, which is inefficient.

This air bleeding operation is performed as follows.

That is, the resist solution is once trapped in the filter container 34. If air is mixed in the resist solution, the air having a low specific gravity rises and accumulates on the resist solution. become.

Here, the upper wall 34c of the filter container 34
Is inclined as shown in FIG.
Is connected, so that air can be reliably stored near the discharge pipe 60.

Next, the CPU 70 sets the air release valve 6
By opening 1 and closing the waste liquid valve 63 and controlling the operation of the vacuum pump 65, the exhaust pipe 60 is evacuated and the air accumulated at the top of the filter container 34 is drawn.

At this time, the resist solution is also drawn in by vacuum evacuation.
Once housed inside.

Then, the air bleeding operation is performed for, for example, about 5 minutes, and thereafter, the air bleeding valve 61 is closed, the waste liquid valve 63 is opened, and the vacuum pump 65 is stopped and controlled to complete the air bleeding operation. The resist solution in the trap 62 is led to the drain via the valve 63 and is wasted.

By closing the waste liquid valve 63 thereafter, the air venting operation is completed.

As described above, since the air bleeding operation is automatically performed in the resist supply path after the elapse of the set time and at the break of the lot, the burden on the operator is greatly reduced, and the resist solution is reduced. In the case of using a plurality of resists, once the set time is set in accordance with the type of the resist solution, the schedule for air bleeding is not required, so that the burden on the operator for management is reduced and the air bleeding process is not executed. Prevention can always ensure proper resist coating operation,
Furthermore, since air is vented at the break between lots, the coating process can be performed efficiently without interruption, and the yield does not decrease.

It is conceivable to arrange a sensor in the air reservoir to detect the amount of air and automatically control the air bleeding operation based on the output of this sensor. It can not be exhibited, it is difficult to put into practical use in terms of reliability, but if the air bleeding operation is performed by time management as in the present embodiment, there is no such adverse effect as described above, and the reliability is improved. I have.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention.

The above-described embodiment is excellent in that the arrangement for executing the air bleeding operation is provided at a stage subsequent to the supply path of the pump 33 so that air mixed in at the time of driving the pump can be eliminated. The side close to the nozzle 30 is good, but the place is not limited, and the air vent is not necessarily performed in the filter container 34. In other words, any place may be used as long as the resist liquid can be trapped.

Further, the various members constituting the coating apparatus are not limited to those described in the above embodiments, and various systems such as a type in which a spin chuck moves up and down together with a motor can be adopted.

Further, the coating apparatus to which the present invention is applied is not limited to the application of a resist to a semiconductor wafer, but can be applied to various coating apparatuses such as a resist to a mask.

[0094]

According to the first aspect of the present invention, when the air accumulated in the upper portion of the trap container is discharged by driving the air discharging means, a set interval time has elapsed and a lot break has occurred. In addition, the air bleeding operation can be automatically performed, the air bleeding operation can be reliably performed, and the burden on the operator can be greatly reduced.

Further, since the air bleeding operation is performed at a break between lots where the resist coating operation has not been performed,
The air can be efficiently removed without interrupting the application operation in the middle of the lot, and the yield is improved.

According to the second aspect of the present invention, when the resist discharging pump is driven, air often mixes with the resist liquid. Has the effect that it can also be eliminated.

According to the third aspect of the present invention, dust and the like can be removed by a filter from the resist solution in which no air is mixed by the trap container.
There is an effect that a more favorable supply of the resist solution can be performed.

According to the fourth aspect of the present invention, when air is mixed in the resist solution, the air having a low specific gravity rises and moves toward the air discharge hole located at a position higher than the resist solution introduction hole. There is an effect that air can be easily stored.

According to the fifth aspect of the present invention, by inclining the wall as described above, there is an effect that air can be reliably stored near the air discharge hole.

According to the sixth aspect of the present invention, when the air in the trap container is sucked by the vacuum pump, the resist solution in the trap container which is sucked simultaneously is accommodated in the waste liquid trap and discharged. There is an effect that can be.

According to the seventh aspect of the present invention, when the air accumulated in the upper portion of the trap container is discharged, the air bleeding operation is automatically performed when the set interval time has elapsed and the lot is a break. Can be executed, the air bleeding operation can be performed reliably, and the burden on the operator can be greatly reduced.Moreover, since the air bleeding operation is performed at a break between lots where the resist coating operation is not performed, The air can be efficiently removed without interrupting the application operation in the middle of the lot, and the yield is improved.

According to the eighth aspect of the present invention, air is often mixed into the resist solution when the resist discharge pump is driven, and such air can be reliably removed by the trap container. effective.

According to the ninth aspect of the present invention, dust and the like can be removed by a filter from the resist solution in which no air is mixed by the trap container.
There is an effect that a more favorable supply of the resist solution can be performed.

According to the tenth aspect of the invention, when the air in the trap container is sucked, the resist solution in the trap container which is sucked simultaneously can be stored in the waste liquid trap and discharged. effective.

[0105]

[Brief description of the drawings]

FIG. 1 is a block diagram of a control system of an air bleeding operation in an apparatus in which the present invention is applied to a semiconductor wafer resist coating apparatus.

FIG. 2 is a schematic explanatory view for explaining the overall configuration of the resist coating apparatus of FIG. 1;

FIG. 3 is a schematic explanatory view for explaining a configuration for bleeding air of the coating apparatus of FIG. 2;

FIG. 4 is a schematic explanatory view for explaining a configuration of air bleeding in a conventional device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 coating material 30 resist nozzle 33 bellows pump 34 filter container as trap container 34 a resist liquid introduction pipe 34 c upper wall 34 b filter 60 air discharge pipe 61 air release valve 62 waste liquid trap 65 vacuum pump 70 CPU 71 time setting unit 72 counter

Continuation of front page (56) References JP-A-62-129178 (JP, A) JP-A-61-11174 (JP, A) JP-A-56-161539 (JP, A) JP-A-61-198723 (JP) JP-A-60-117727 (JP, A) JP-A-58-35952 (JP, U) JP-A-59-77225 (JP, U) JP-A-62-37923 (JP, U) JP-A 60-112379 (JP, U) Japan Institute of Invention and Innovation Technical Publication No. 85-2201

Claims (10)

(57) [Claims] 1. A resist coating apparatus for applying a resist solution by dripping a resist solution onto a surface of a material to be coated, wherein a trap container disposed in a resist solution supply path and air trapped in an upper portion of the trap container are sucked and discharged. Air discharging means, an interval time for discharging air accumulated in the trap container at predetermined time intervals, first determining means for determining whether or not this interval time has elapsed, A second process for determining whether or not the end of the processing of one lot and before the start of processing of the next lot is a break of the lot.
And the first determining means determines that the set interval time has elapsed, and if the second determining means determines that it is a break between lots, the air discharging means is driven. And a control means for automatically controlling an air discharging operation. 2. The resist container according to claim 1, further comprising: a resist nozzle for dropping a resist solution onto a surface of the material to be coated, and a resist discharge pump for supplying a resist solution to the resist nozzle. A resist coating apparatus, which is disposed in a resist liquid supply path from a resist discharge pump to a resist nozzle. 3. The resist coating apparatus according to claim 2, wherein the resist liquid supplied into the trap container is supplied to the resist nozzle via a filter. 4. The trap container according to claim 1, wherein the trap container has a resist liquid introduction hole and an air discharge hole, and the resist liquid introduction hole is arranged below the air discharge port. A resist coating apparatus characterized in that: 5. The trap container according to claim 4, wherein a wall portion located between the resist liquid introduction hole and the air discharge hole is inclined from the resist liquid introduction hole side to the air discharge hole side. A resist coating apparatus. 6. The air discharge means according to claim 1, wherein the air discharging means is provided between the trap container and the vacuum pump, and a vacuum pump for sucking air accumulated in an upper portion of the trap container. And a waste liquid trap disposed between the vacuum pump and the air release valve. 7. A resist coating method in which a resist liquid is dropped and applied from a resist nozzle onto a surface of a material to be coated through a trap container provided in the middle of a resist liquid supply path, wherein air trapped in the trap container is removed. A step of presetting an interval time for discharging every predetermined time and determining whether or not this interval time has elapsed; A step of determining whether or not it is a lot break; and a step of automatically discharging the air accumulated in the trap container at the break of the lot after the interval time has elapsed. Resist coating method. 8. The method according to claim 7, wherein in the resist solution supply path, while the resist solution is supplied from the resist discharge pump to the resist nozzle,
A resist coating method comprising: storing a resist solution in the trap container; and supplying the resist solution from the trap container to the resist nozzle. 9. The resist coating method according to claim 7, wherein the resist liquid supplied into the trap container is supplied to a resist nozzle via a filter. 10. In the step of discharging air from the trap container, the air in the trap container is sucked, and the resist solution sucked together with the air is stored in a waste liquid trap and discharged. Method.