JP2018046269A - Process liquid supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process liquid supply device which can properly remove particles in a process liquid with a filter regardless of a physical relationship and pipelines of each part in the device and installation conditions etc.SOLUTION: A resist liquid supply device 200 supplies a resist liquid to a coating nozzle 142 and includes: a buffer tank 202 which temporarily stores a process liquid supplied from a resit liquid supply source 201 which stores the resist liquid; a filter 212 which is provided between the coating nozzle 142 and the buffer tank 202 and removes foreign objects in the resist liquid; and a pump 211 which pumps the resist liquid, from which the foreign objects are removed by the filter 212, to the coating nozzle 142. The buffer tank 202 has a pumping function which pumps the resist liquid stored in the buffer tank 202.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a processing liquid supply apparatus that supplies a processing liquid such as a resist liquid to a target object via a processing liquid discharge unit.

  In a photolithography process in a manufacturing process of a semiconductor device or the like, a resist film is used to form a coating film such as an antireflection film or a resist film on a target object such as a semiconductor wafer or to develop a resist film after exposure. A processing solution such as a solution or a developer is used.

The processing liquid may contain foreign matter (particles). In addition, even if there are no particles in the original processing liquid, if particles adhere to the system path such as the pump, valve, or pipe of the apparatus that supplies the processing liquid, the particles are mixed in the processing liquid to be supplied. Sometimes. Therefore, a filter is disposed in the system path of the apparatus for supplying the processing liquid, and particles are removed by the filter (Patent Document 1).
In addition, in the processing liquid supply apparatus of Patent Document 1, a buffer tank that temporarily stores a processing liquid is provided to prevent the operation of the apparatus from being stopped when the resist liquid supply source that stores the processing liquid is replaced. It is provided between the supply source and the filter.

JP 2013-211525 A

By using a filter as in the treatment liquid supply apparatus of Patent Document 1, particles in the treatment liquid can be collected / removed. The collection efficiency of the filter particles depends on the liquid pressure of the treatment liquid when passing through the filter. It depends on.
However, the liquid pressure of the processing liquid when passing through the filter may not be desired due to the positional relationship between the buffer tank and the filter, the piping between the two, and the like. In addition, for example, when the processing liquid supply device is installed at a high altitude, a desired pressure may not be obtained as the processing liquid pressure when passing through the filter.

  The present invention has been made in view of such points, and a processing liquid supply capable of appropriately removing particles in the processing liquid with a filter regardless of the positional relationship of each part in the apparatus, piping, installation conditions, and the like. The object is to provide a device.

  In order to achieve the above object, the present invention provides a processing liquid supply apparatus for supplying a processing liquid to a processing liquid discharge section that discharges the processing liquid to an object to be processed. The processing liquid supply source stores the processing liquid. A temporary storage device that temporarily stores the processing liquid supplied from the filter, a filter that removes foreign matter in the processing liquid from the temporary storage device, and a processing liquid from which the foreign matter has been removed by the filter The temporary storage device has a pumping function of pumping the processing liquid stored in the temporary storage device.

  A pressure measuring device that is provided downstream of the temporary storage device and measures the liquid pressure of the processing liquid, and controls at least the pumping of the processing liquid from the temporary storage device based on the measurement result of the pressure measuring device. And a control device.

  The pressure measuring device measures the fluid pressure on the secondary side of the filter, and the control device controls the fluid pressure at the time of the pumping so that the fluid pressure on the secondary side of the filter is constant. Is preferred.

  The pressure measuring device measures a fluid pressure on the secondary side of the filter, and the control device applies a predetermined pressure to the temporary storage device when the fluid pressure on the secondary side of the filter is within a predetermined range. Pressure may be applied to pump the treatment liquid.

  The pressure measuring device measures the hydraulic pressure on the primary side of the filter, and the control device controls the hydraulic pressure at the time of the pumping so that the hydraulic pressure on the primary side of the filter is constant. Also good.

  A plurality of sets of the temporary storage device, the filter, and the pump are provided, and the control device adjusts a hydraulic pressure in a storage chamber that is provided for each of the temporary storage devices and stores the processing liquid of the temporary storage device. It is preferable to have an electropneumatic regulator.

  The temporary storage device can be constituted by a tube diaphragm pump.

  A plurality of sets of the temporary storage device, the filter, and the pump are provided, and each of the temporary storage devices includes a storage device that stores the processing liquid and a separate pump that pumps the processing liquid in the storage device. A common electropneumatic regulator is provided for adjusting the hydraulic pressure in the storage chamber for storing the processing liquid of the other pump with respect to the other pump of the temporary storage device. Control of the liquid pressure during the pumping of the processing liquid may be performed by the electropneumatic regulator.

  The another pump may be a tube diaphragm pump.

  The pump preferably sends the processing liquid from which foreign substances have been removed by the filter so as to pass through the filter again when the processing liquid is sent to the processing liquid discharge section.

  A treatment liquid supply pipe provided with the temporary storage device, the filter, and the pump in order from the upstream side, and the pump has a storage chamber for storing the treatment liquid, and the treatment liquid supply pipe is One valve is provided between the temporary storage device and the filter, and another valve is provided between the temporary storage device and the filter, and the control device moves from the temporary storage device to the storage chamber of the pump. When replenishing the processing liquid from which foreign substances have been removed by the filter, the pressure on the secondary side of the filter measured by the pressure measuring device with the one valve opened and the other valve closed is a predetermined value. So that the pressure of the processing liquid from the temporary storage device is controlled, and then the secondary valve of the filter measured by the pressure measuring device with the one valve closed and the other valve opened. Side pressure is the predetermined As a value, since the control pressure in the storage chamber, it is preferable to start the replenishment while opening the said one valve and the other valve.

  According to the treatment liquid supply apparatus of the present invention, particles in the treatment liquid can be appropriately removed by the filter regardless of the positional relationship among the parts in the apparatus, piping, installation conditions, and the like.

It is a top view which shows the outline of a structure of the substrate processing system which concerns on embodiment of this invention. It is a front view which shows the outline of a structure of the substrate processing system which concerns on embodiment of this invention. It is a rear view which shows the outline of a structure of the substrate processing system which concerns on embodiment of this invention. It is a longitudinal cross-sectional view which shows the outline of a structure of a resist coating device. It is a cross-sectional view which shows the outline of a structure of a resist coating apparatus. It is explanatory drawing which shows the outline of a structure of the resist coating device which concerns on 1st Embodiment. It is a model external view explaining a buffer tank. It is explanatory drawing of the structure of a buffer tank. It is an explanatory view of the state where the piping system for explaining the outline of the composition of a resist solution supply device was shown, and the replenishment process to a buffer tank was carried out. It is explanatory drawing of the state which showed the piping system for demonstrating the outline of a structure of a resist liquid supply apparatus, and implemented the replenishment process to a pump. FIG. 5 is a diagram illustrating a coating system for explaining an outline of a configuration of a resist solution supply apparatus, and is an explanatory diagram of a coating process. It is explanatory drawing of the process which shows the piping system for demonstrating the outline of a structure of a resist liquid supply apparatus, and returns a resist liquid to a buffer tank. It is a figure explaining another example of the control at the time of pumping from a buffer tank. It is explanatory drawing which shows the outline of a structure of the resist liquid supply apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows the outline of a structure of the resist liquid supply apparatus which concerns on the form of a comparison. It is explanatory drawing which shows the outline of a structure of the resist liquid supply apparatus which concerns on the 3rd Embodiment of this invention. It is explanatory drawing which shows the outline of a structure of the resist liquid supply apparatus which concerns on the 4th Embodiment of this invention. FIG. 5 is a diagram illustrating a piping system for explaining an outline of the configuration of the resist solution supply apparatus, and is an explanatory diagram of a pump replenishment process or a vent process. It is an explanatory view of a replenishment process to a pump, showing a piping system for explaining an outline of a configuration of a resist solution supply apparatus. It is an explanatory view of a replenishment process to a pump, showing a piping system for explaining an outline of a configuration of a resist solution supply apparatus. FIG. 7 is a diagram illustrating a piping system for explaining an outline of a configuration of a resist solution supply apparatus, and is an explanatory diagram of another replenishment process for a pump. It is explanatory drawing of the state which showed the piping system for demonstrating the outline of a structure of a resist liquid supply apparatus, and implemented the application | coating process. The piping system for demonstrating the outline of a structure of a resist liquid supply apparatus is shown, and another application | coating process is explanatory drawing of an implementation body state. It is an explanatory view of a vent process, showing a piping system for explaining an outline of a configuration of a resist solution supply apparatus. It is an explanatory view of a vent process, showing a piping system for explaining an outline of a configuration of a resist solution supply apparatus. It is an explanatory view of a vent process, showing a piping system for explaining an outline of a configuration of a resist solution supply apparatus. It is a descriptive drawing of another vent process which shows the piping system for explaining the outline of the composition of a resist solution supply device. It is a figure which shows the quantity of the particle | grains observed in the resist film of an Example and a comparative example.

(First embodiment)
Embodiments of the present invention will be described below. FIG. 1 is an explanatory diagram showing an outline of the configuration of a substrate processing system 1 equipped with a resist solution supply apparatus as a process liquid supply apparatus according to the first embodiment of the present invention. 2 and 3 are a front view and a rear view, respectively, schematically showing the outline of the internal configuration of the substrate processing system 1. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 1, the substrate processing system 1 includes a cassette station 10 in which a cassette C containing a plurality of wafers W is loaded and unloaded, and a processing station 11 having a plurality of various processing apparatuses for performing predetermined processing on the wafers W. And an interface station 13 that transfers the wafer W to and from the exposure apparatus 12 adjacent to the processing station 11 is integrally connected.

  The cassette station 10 is provided with a cassette mounting table 20. The cassette mounting table 20 is provided with a plurality of cassette mounting plates 21 on which the cassette C is mounted when the cassette C is carried into and out of the substrate processing system 1.

  As shown in FIG. 1, the cassette station 10 is provided with a wafer transfer device 23 that is movable on a transfer path 22 that extends in the X direction. The wafer transfer device 23 is also movable in the vertical direction and the vertical axis direction (θ direction), and includes a cassette C on each cassette mounting plate 21 and a delivery device for a third block G3 of the processing station 11 described later. The wafer W can be transferred between the two.

  The processing station 11 is provided with a plurality of, for example, four blocks G1, G2, G3, and G4 having various devices. For example, the first block G1 is provided on the front side of the processing station 11 (X direction negative direction side in FIG. 1), and the second block is provided on the back side of the processing station 11 (X direction positive direction side in FIG. 1). Block G2 is provided. A third block G3 is provided on the cassette station 10 side (Y direction negative direction side in FIG. 1) of the processing station 11, and the interface station 13 side (Y direction positive direction side in FIG. 1) of the processing station 11 is provided. Is provided with a fourth block G4.

  For example, in the first block G1, as shown in FIG. 2, a plurality of liquid processing apparatuses, for example, a development processing apparatus 30 that develops the wafer W, an antireflection film (hereinafter referred to as “lower antireflection") A lower antireflection film forming device 31 for forming a film), a resist coating device 32 for applying a resist solution to the wafer W to form a resist film, and an antireflection film (hereinafter referred to as “upper reflection” on the resist film of the wafer W). An upper antireflection film forming device 33 for forming an “antireflection film” is arranged in this order from the bottom.

  For example, three development processing devices 30, a lower antireflection film forming device 31, a resist coating device 32, and an upper antireflection film forming device 33 are arranged in a horizontal direction. The number and arrangement of the development processing device 30, the lower antireflection film forming device 31, the resist coating device 32, and the upper antireflection film forming device 33 can be arbitrarily selected.

  In the liquid processing apparatuses such as the development processing apparatus 30, the lower antireflection film forming apparatus 31, the resist coating apparatus 32, and the upper antireflection film forming apparatus 33, for example, spin coating for applying a predetermined processing liquid onto the wafer W is performed. In spin coating, for example, the processing liquid is discharged onto the wafer W from an application nozzle, and the wafer W is rotated to diffuse the processing liquid to the surface of the wafer W.

  For example, in the second block G2, as shown in FIG. 3, a heat treatment apparatus 40 for performing heat treatment such as heating and cooling of the wafer W, an adhesion apparatus 41 for improving the fixability between the resist solution and the wafer W, and the wafer W A peripheral exposure device 42 for exposing the outer peripheral portion is provided side by side in the vertical direction and the horizontal direction. The number and arrangement of the heat treatment apparatus 40, the adhesion apparatus 41, and the peripheral exposure apparatus 42 can be arbitrarily selected.

  For example, in the third block G3, a plurality of delivery devices 50, 51, 52, 53, 54, 55, and 56 are provided in order from the bottom. The fourth block G4 is provided with a plurality of delivery devices 60, 61, 62 in order from the bottom.

  As shown in FIG. 1, a wafer transfer region D is formed in a region surrounded by the first block G1 to the fourth block G4. In the wafer transfer region D, for example, a plurality of wafer transfer devices 70 having transfer arms 70a that are movable in the Y direction, the X direction, the θ direction, and the vertical direction are arranged. The wafer transfer device 70 moves in the wafer transfer area D and transfers the wafer W to a predetermined device in the surrounding first block G1, second block G2, third block G3, and fourth block G4. it can.

  Further, in the wafer transfer region D, a shuttle transfer device 80 that transfers the wafer W linearly between the third block G3 and the fourth block G4 is provided.

  The shuttle conveyance device 80 is linearly movable in the Y direction of FIG. 3, for example. The shuttle transfer device 80 moves in the Y direction while supporting the wafer W, and can transfer the wafer W between the transfer device 52 of the third block G3 and the transfer device 62 of the fourth block G4.

  As shown in FIG. 1, a wafer transfer apparatus 100 is provided next to the third block G3 on the positive side in the X direction. The wafer transfer apparatus 100 has a transfer arm that is movable in the X direction, the θ direction, and the vertical direction, for example. The wafer transfer device 100 can move up and down while supporting the wafer W, and can transfer the wafer W to each delivery device in the third block G3.

  The interface station 13 is provided with a wafer transfer device 110 and a delivery device 111. The wafer transfer device 110 includes a transfer arm 110a that is movable in the Y direction, the θ direction, and the vertical direction, for example. For example, the wafer transfer device 110 can support the wafer W on the transfer arm 110a and transfer the wafer W between each transfer device, the transfer device 111, and the exposure device 12 in the fourth block G4.

  Next, the configuration of the resist coating apparatus 32 will be described. FIG. 4 is a longitudinal sectional view showing an outline of the configuration of the resist coating apparatus 32, and FIG. 5 is a transverse sectional view showing an outline of the configuration of the resist coating apparatus 32.

  As shown in FIG. 4, the resist coating apparatus 32 has a processing container 120 whose inside can be closed. As shown in FIG. 5, a loading / unloading port 121 for the wafer W is formed on the side surface of the processing container 120, and an opening / closing shutter 122 is provided at the loading / unloading port 121.

  A spin chuck 130 for holding and rotating the wafer W is provided at the center of the processing container 120 as shown in FIG. The spin chuck 130 has a horizontal upper surface, and a suction port (not shown) for sucking the wafer W, for example, is provided on the upper surface. By suction from the suction port, the wafer W can be sucked and held on the spin chuck 130.

  The spin chuck 130 has a chuck drive mechanism 131 including a motor, for example, and can be rotated at a predetermined speed by the chuck drive mechanism 131. Further, the chuck drive mechanism 131 is provided with an elevating drive source such as a cylinder, and the spin chuck 130 can move up and down.

  Around the spin chuck 130, a cup 132 that receives and collects the liquid scattered or dropped from the wafer W is provided. A discharge pipe 133 that discharges the collected liquid and an exhaust pipe 134 that exhausts the atmosphere in the cup 132 are connected to the lower surface of the cup 132.

  As shown in FIG. 5, a rail 140 extending along the Y direction (left and right direction in FIG. 5) is formed on the X direction negative direction (downward direction in FIG. 5) side of the cup 132. The rail 140 is formed, for example, from the outside of the cup 132 in the Y direction negative direction (left direction in FIG. 5) to the outside in the Y direction positive direction (right direction in FIG. 5). An arm 141 is attached to the rail 140.

  As shown in FIGS. 4 and 5, a coating nozzle 142 that discharges a resist solution is supported on the arm 141. The arm 141 is movable on the rail 140 by a nozzle driving unit 143 shown in FIG. Thereby, the coating nozzle 142 can move from the standby part 144 installed outside the Y direction positive direction side of the cup 132 to above the center part of the wafer W in the cup 132, and further on the surface of the wafer W It can move in the radial direction of W. The arm 141 can be moved up and down by a nozzle driving unit 143, and the height of the application nozzle 142 can be adjusted. The coating nozzle 142 is connected to a resist solution supply apparatus 200 that supplies a resist solution as shown in FIG.

  Next, the configuration of the resist solution supply device 200 that supplies the resist solution to the coating nozzle 142 as the processing solution discharge unit in the resist coating device 32 will be described. FIG. 6 is an explanatory diagram showing an outline of the configuration of the resist solution supply apparatus 200. FIG. 7 is a schematic external view illustrating the buffer tank. Note that the resist solution supply apparatus 200 is provided, for example, in a chemical chamber (not shown). The chemical chamber is for supplying various processing liquids to the liquid processing apparatus.

  A resist solution supply apparatus 200 in FIG. 6 includes a resist solution supply source (an example of a “processing solution supply source” according to the present invention) 201 that stores a resist solution therein, and a resist solution transferred from the resist solution supply source 201. A buffer tank (a “temporary storage device” according to the present invention) 202 that temporarily stores

  The resist solution supply source 201 is replaceable, and a first processing solution supply pipe 251 for transferring the resist solution to the buffer tank 202 is provided above the resist solution supply source 201. A supply valve 203 is provided in the first processing liquid supply pipe 251.

  Further, on the downstream side of the supply valve 203 in the first processing liquid supply pipe 251, there is an air supply pipe 252 connected to a pressurization source 204 for pressurizing the buffer tank 202 and discharging the resist liquid in the tank 202. Is provided. A switching valve 205 is provided in the air supply pipe 252.

  The buffer tank 202 temporarily stores the resist solution transferred from the replaceable resist solution supply source 201 and has a pressure-feeding function for pumping the stored processing solution. The buffer tank 202 is constituted by a tube diaphragm pump, for example, and includes a flexible diaphragm 202a as shown in FIG. 7, and a storage chamber 202b for temporarily storing a resist solution is formed by the diaphragm 202a. ing. The capacity of the storage chamber 202b is variable as the diaphragm 202a is deformed. Therefore, even when the resist solution supply source 201 is replaced, the contact between the resist solution and the gas in the storage chamber 202b can be minimized. it can.

  A drain pipe 253 used for discharging the resist solution in the tank 202 is provided above the buffer tank 202, and a discharge valve 206 is provided in the drain pipe 253.

  Further, an electropneumatic regulator 207 for deforming the diaphragm 202 a is connected to the buffer tank 202 via a supply / exhaust pipe 254. The electropneumatic regulator 207 is connected with an air supply pipe 255 connected to the pressurization source 208 and an exhaust pipe 256 connected to the pressure reduction source 209. The diaphragm 202a can be deformed by adjusting the pressure by the pressure source 208 and the pressure by the pressure source 209. The air supply / exhaust pipe 254 is provided with a pressure sensor 210 that measures the pressure (atmospheric pressure) in the pipe line, that is, the pressure for deforming the diaphragm 202a.

8A and 8B are explanatory views of the structure of the buffer tank 202. FIG. 8A is an external view, FIG. 8B is a cross-sectional view showing only an outer peripheral wall described later, and FIG. It is A sectional drawing.
The tube diaphragm pump constituting the buffer tank 202 has a diaphragm 202a and an outer peripheral wall 202c, for example, as shown in FIG. In this buffer tank 202, a space formed by a cylindrical outer peripheral wall 202c is partitioned into a storage chamber 202b and a working chamber 202d by a flexible diaphragm 202a. By controlling the pressure in the working chamber 202d by the electropneumatic regulator 207, the resist solution is transferred from the resist solution supply source 201 to the storage chamber 202b, or the resist solution is pumped from the storage chamber 202b at a desired liquid pressure. be able to.

  An inlet port 202e to which the first processing liquid supply pipe 251 and the drain pipe 253 are connected is provided at the upper end of the diaphragm 202a, and a second processing liquid supply pipe 257, which will be described later, is connected to the lower end. An outgoing port 202f is provided. In addition, a connection port 202g to which the air supply / exhaust pipe 254 is connected is provided on the upper portion of the outer peripheral wall 202c.

  In addition, the diaphragm 202a and the outer peripheral wall 202c are formed, for example with a fluororesin. By using a fluororesin, it is transparent so that the state of the resist solution inside can be detected by a photoelectric sensor or the like, and the diaphragm 202a and the outer peripheral wall 202c are welded together to seal the outer peripheral wall 202c and operate. A chamber 202d can be formed.

Returning to the description of FIG.
A second processing liquid supply pipe 257 for transferring the resist liquid to the pump 211 is provided below the buffer tank 202. In other words, the pump 211 is provided on the downstream side of the buffer tank 202 in the second processing liquid supply pipe 257.

In addition, a filter 212 for removing particles in the resist solution is provided between the buffer tank 202 and the pump 211 in the second processing solution supply pipe 257. The filter 212 is provided with a drain pipe 258 for discharging bubbles generated in the resist solution. The drain pipe 258 is provided with a discharge valve 213.
Further, a supply valve 214 is provided upstream of the filter 212 in the second processing liquid supply pipe 257, and a switching valve 215 is provided between the filter 212 and the pump 211 in the second processing liquid supply pipe 257. Yes.

  The pump 211 is a tube diaphragm pump, for example. The pump 211 has a storage chamber (not shown) for storing a resist solution, and an electropneumatic regulator 216 for controlling the discharge amount of the resist solution from the pump 211 is provided with a supply / exhaust pipe 259. Connected through. The electropneumatic regulator 216 is connected to an air supply pipe 260 connected to the pressurization source 217 and an exhaust pipe 261 connected to the decompression source 218.

  The pump 211 is provided with a third processing liquid supply pipe 262 that supplies a resist liquid from the pump 211 to the wafer as the object to be processed through the coating nozzle 142. The third processing liquid supply pipe 262 is provided with a pressure sensor 219 that measures the liquid pressure of the resist liquid in the third processing liquid supply pipe 262.

  Further, a switching valve 220 is provided on the downstream side of the pressure sensor 219 in the third processing liquid supply pipe 262, and a supply control valve 221 is provided on the downstream side of the switching valve 220 and in the vicinity of the coating nozzle 142. Is provided.

  Further, the resist solution supply apparatus 200 includes a return pipe 263 for returning the resist solution in the pump 211 to the buffer tank 202. One end of the return pipe 263 is connected between the pressure sensor 219 and the switching valve 220 in the third processing liquid supply pipe 262, and the other end is connected to the supply valve 214 and the filter 212 in the second processing liquid supply pipe 257. Connected between. The return pipe 263 is provided with a return control valve 222.

  The resist solution supply apparatus 200 includes a control unit (not shown). As each valve provided in the resist solution supply apparatus 200, an electromagnetic valve or an air operated valve that can be controlled by the control unit is used, and each valve and the control unit are electrically connected. The control unit is electrically connected to the pressure sensor 210, the pressure sensor 219, and the electropneumatic regulators 207 and 216. With this configuration, a series of processes in the resist solution supply apparatus 200 can be automatically performed under the control of the control unit. The “control device” of the present invention includes, for example, the control unit and electropneumatic regulators 207 and 216.

  Next, the operation of the resist solution supply apparatus 200 will be described with reference to FIGS.

(Refilling the buffer tank 202)
As shown in FIG. 9, based on the control signal from the control unit, the supply valve 203 provided in the first processing liquid supply pipe 251 is opened, and the electropneumatic regulator 207 and the decompression source 209 are used to buffer the supply valve 203. The inside of the storage chamber 202b of the tank 202 is depressurized, whereby the resist solution is supplied from the resist solution supply source 201 into the storage chamber 202b of the buffer tank 202. At this time, the pressure in the storage chamber 202 b, that is, the pressure in the working chamber 202 d is subjected to footback control based on the measurement result of the pressure sensor 210.
In FIG. 9 and the subsequent figures, the valve in the open state is painted white, the valve in the closed state is painted black, and the pipe through which a fluid such as a resist solution circulates is indicated by a bold line, Description of the open / closed state of is omitted.

(Replenishment to the pump 211)
When a predetermined amount of resist solution is supplied / supplemented into the storage chamber 202b of the buffer tank 202, as shown in FIG. 10, the supply valve 203 is closed, and the second treatment solution supply pipe 257 is interposed. The supply valve 214 and the switching valve 215 are opened. At the same time, the electropneumatic regulator 207 switches the connection destination of the buffer tank 202 to the pressurizing source 208 and pressurizes the storage chamber 202b of the buffer tank 202, whereby the resist solution in the storage chamber 202b is removed from the buffer tank 202 to the second. To the processing liquid supply pipe 257. The resist solution thus pumped is transferred to the pump 211 after passing through the filter 212. At this time, the pressure sensor 219 measures the pressure in the third processing liquid supply pipe 262, that is, the pressure in the pump 211 communicating with the supply pipe 262 that is equal to the pressure on the secondary side of the filter 212. Based on the measurement result, the hydraulic pressure when the processing liquid is pumped from the storage chamber 202b of the buffer tank 202 is the desired value of the secondary pressure of the filter 212 measured by the pressure sensor 219. Is feedback controlled.

(vomit)
When a predetermined amount of resist solution is supplied / supplemented into the pump 211, as shown in FIG. 11, the supply valve 214 and the switching valve 215 are closed, and the switching provided in the third processing solution supply pipe 262 is performed. The valve 220 and the supply control valve 221 are opened. At the same time, the connection destination of the pump 211 is switched to the pressurizing source 217 by the electropneumatic regulator 216, and the resist solution is pumped from the pump 211 to the third processing solution supply pipe 262. Thereby, a part (for example, 1/5) of the resist solution transferred to the pump 211 is discharged onto the wafer through the coating nozzle 142. At this time, the pressure in the pump 211 is foot-back controlled based on the measurement result of the pressure in the third processing liquid supply pipe 262 by the pressure sensor 219.

(return)
When a predetermined amount of resist solution is discharged from the pump 211, as shown in FIG. 12, the switching valve 220 and the supply control valve 221 are closed, and the return control valve 222 and the supply valve 214 are opened. At the same time, the electropneumatic regulator 216 is controlled based on the measurement results of the pressure sensor 210 and the pressure sensor 219 so that the pressure of the pump 211 becomes larger than the pressure in the storage chamber 202b of the buffer tank 202. As a result, the remaining resist solution (for example, 4/5) in the pump 211 is returned to the buffer tank 202 via the return pipe 263.

  Thereafter, the above operation is repeated.

As described above, the resist solution supply apparatus 200 has not only a function for the buffer tank 202 to temporarily store the processing solution, but also a pressure feeding function for pumping the processing solution.
Therefore, the resist solution supply apparatus 200 has the following effects. That is, if the buffer tank is a conventional one, the liquid pressure in the filter 212 cannot be set to a desired value when the resist solution is replenished from the buffer tank to the pump 211 depending on the apparatus installation conditions and the layout in the apparatus. However, in the resist solution supply apparatus 200, since the buffer tank 202 has a pressure feeding function, the resist solution supply apparatus 200 refills the pump 211 with the resist solution even under the same apparatus installation conditions and in-apparatus layout. Further, the hydraulic pressure in the filter 212 can be set to a desired value.

  In particular, based on the liquid pressure of the resist solution in the third processing liquid supply pipe 262 measured by the pressure sensor 219, that is, the liquid pressure on the secondary side of the filter 212, the liquid pressure on the secondary side is a predetermined value. The fluid pressure (hereinafter referred to as “pressure feeding fluid pressure”) when feeding from the buffer tank 202 is feedback controlled so as to be constant. Therefore, when the resist solution is replenished from the buffer tank 202 to the pump 211, the fluid pressure in the filter 212 can be more reliably set to a desired value.

  Note that when the resist solution passes through the filter 212, the flow velocity increases, so that the liquid pressure of the resist solution decreases. When the resist solution decreases to the saturated vapor pressure, bubbles are generated in the resist solution due to the principle of cavitation. . However, in the resist solution supply apparatus 200, the fluid pressure on the secondary side of the filter 212 is controlled, and the generation of bubbles can be suppressed by making the static pressure level higher than the saturated vapor pressure.

Further, the buffer tank 202 is a deformed storage chamber 202b for storing the resist solution. Therefore, there are the following effects.
When there is no resist solution in the resist solution supply source 201 and the resist solution in the storage chamber of the buffer tank is reduced, if the buffer solution is a normal buffer tank, the liquid level of the resist solution in the storage chamber is lowered, and the inner peripheral surface of the storage chamber And the air may dry out as a result, resulting in defects in the processed wafer.
On the other hand, in the resist solution supply apparatus 200, the storage chamber 202b of the buffer tank 202 is deformed as described above, so that even if the amount of the resist solution in the storage chamber 202b decreases, the inner peripheral surface of the storage chamber 202b touches the air. You can prevent it from drying out.

  Note that the resist solution in the buffer tank 202 can be discharged through the second treatment liquid supply pipe 257 and the third treatment liquid supply pipe 262 using the pressure source 204. Further, the pressurization source 204 can be used also when liquid passing through the return pipe 263 and the filter 212 is performed. At the time of liquid passing through the filter 212, the resist liquid is discharged through the drain pipe 258.

  Further, although not shown in the figure, a pressure source may be provided in the resist solution supply source 201 in order to pass the resist solution through the buffer tank 202 and the first processing solution supply pipe 251. At the time of the liquid passing treatment, the resist solution is discharged through the drain pipe 253.

(Other examples of pumping control)
In the above example, the feed hydraulic pressure is feedback controlled so that the secondary side hydraulic pressure of the filter 212 is constant at a predetermined value. However, instead of this, when the hydraulic pressure on the secondary side of the filter 212 measured by the pressure sensor 219 is within a predetermined range and no abnormality is found in the measurement result, the following may be performed. In other words, a predetermined constant pressure is applied to the buffer tank 202, more specifically, to the storage chamber 202b of the buffer tank 202 using the electropneumatic regulator 207, so that the processing liquid is pumped from the buffer tank 202. May be.

(Another example of pumping control)
FIG. 13 is a diagram for explaining another example of control at the time of pumping from the buffer tank 202.
In the resist solution supply apparatus 200 of FIG. 13, a pressure sensor 223 that measures the liquid pressure in the second processing liquid supply pipe 257 is provided between the buffer tank 202 and the supply valve 214 in the second processing liquid supply pipe 257. Is provided.
The electropneumatic regulator 207 may be used to feedback-control the hydraulic pressure so that the primary hydraulic pressure of the filter 212 measured by the pressure sensor 223 becomes constant at a predetermined value.

(Second Embodiment)
FIG. 14 is an explanatory diagram showing an outline of the configuration of a resist solution supply apparatus according to the second embodiment of the present invention. FIG. 15 is a diagram schematically illustrating the configuration of a resist solution supply apparatus according to a comparative embodiment.
Since the configuration downstream of the buffer tank of the resist solution supply apparatus according to the present embodiment and the comparative embodiment is the same as that of the resist solution supply apparatus 200 of FIG.

  14 is different from the resist solution supply apparatus 200 of FIG. 6 in that two buffer tanks 202 are provided for the resist solution supply source 201. In the resist solution supply apparatus 300, an electropneumatic regulator 207 is provided for each buffer tank 202, and a different pressure can be applied to each storage chamber 202b of the buffer tank 202.

On the other hand, the resist solution supply apparatus 300 ′ in FIG. 15 is provided with a common electropneumatic regulator 207 for the two buffer tanks 202. Therefore, the pressure that can be applied to the storage chamber 202b of the buffer tank 202 is the same in the two storage chambers 202b.
Therefore, the resist solution supply apparatus 300 ′ has the following problems. When replenishment from the resist solution supply source 201 to the buffer tank 202 becomes impossible, when the resist solution is pumped from one buffer tank 202, the diaphragm 202a is deformed so that the storage chamber 202b of the one buffer tank 202 is reduced. It will not return to its original form. Accordingly, the resist solution cannot be pumped at a desired pressure unless a larger pressure is applied to the storage chamber 202b of the one buffer tank 202. However, when the pressure in the storage chamber 202b of the one buffer tank 202 is increased, the pressure in the storage chamber 202b of the other buffer tank 202 at which a desired pressure can be obtained also increases, The pressure when pumping from the storage chamber 202b becomes larger than desired.

  Thus, the resist solution supply apparatus 300 ′ has a problem when the resist solution supply source 201 cannot be replenished to the buffer tank 202, that is, when the resist solution supply source 201 is replaced.

  On the other hand, in the resist solution supply apparatus 300 of FIG. 14, since different pressures can be applied to the storage chambers 202b of the buffer tank 202, the storage chamber 202b of the buffer tank 202 is reduced when the resist solution supply source 201 is replaced. Even when deformed, the resist solution can be pumped from the buffer tank 202 at a desired pressure.

  Note that, in the resist solution supply apparatus 300, the pumping fluid pressure from the buffer tank 202 is feedback controlled so that, for example, the fluid pressure on the secondary side of the filter 212 measured by the pressure sensor 219 is constant at a predetermined value. The Similarly to the first embodiment, when the hydraulic pressure on the secondary side of the filter 212 measured by the pressure sensor 219 is within a predetermined range, an electropneumatic regulator 207 is provided in the storage chamber 202b of the buffer tank 202. The processing liquid may be pumped from the buffer tank 202 by applying a predetermined constant pressure. Further, a pressure sensor for measuring the liquid pressure in the second processing liquid supply pipe 257 is provided, and the electropneumatic pressure is adjusted so that the liquid pressure on the primary side of the filter 212 measured by the pressure sensor becomes constant at a predetermined value. The regulator 207 may be used to perform feedback control of the pumping fluid pressure from the buffer tank 202.

  Further, even if the buffer tank 202 has a common electropneumatic regulator 207 as in the resist solution supply apparatus 300 ′ of FIG. 13, the reaction force is small even if the diaphragm 202a in the buffer tank 202 is deformed. Does not cause a problem when the resist solution supply source 201 is replaced.

  In the resist solution supply apparatus 300 ′, the switching valve 301 is provided in the supply / exhaust pipe 254 connecting the buffer tank 202 and the electropneumatic regulator 207. Further, the buffer tank 202 is provided with an exhaust pipe 351 connected to a decompression source 302, and the exhaust pipe 351 is provided with an exhaust valve 303. In the resist solution supply apparatus 300 ′, when the resist solution is replenished to the buffer tank 202, the switching valve 301 is closed, the supply valve 203 is opened, and the exhaust valve 303 is opened. As a result, the pressure in the storage chamber 202b of the buffer tank 202 is reduced. As a result, the resist solution is supplied from the resist solution supply source 201 into the storage chamber 202b of the buffer tank 202.

(Third embodiment)
FIG. 16 is an explanatory diagram showing an outline of the configuration of a resist solution supply apparatus according to the third embodiment of the present invention.
The resist solution supply apparatus 400 of FIG. 16 is provided with a common electropneumatic regulator 207 for the two buffer tanks 202, similarly to the resist solution supply apparatus 300 ′ of FIG. However, unlike the resist solution supply apparatus 300 ′ in FIG. 15, the resist solution supply apparatus 400 in FIG. 16 has another buffer between the resist solution supply source 201 and the buffer tank 202 in the first processing liquid supply pipe 251. A tank 401 is provided. The other buffer tank 401 is a normal tank that does not have a pressure feeding function.

In this resist solution supply apparatus 400, in a state where the resist solution supply source 201 is empty, the resist solution is pumped from one buffer tank 202, and the diaphragm 202a is reduced so that the storage chamber 202b of the one buffer tank 202 is reduced. Even if deformed, the resist solution is replenished from the other buffer tank 401 to the one buffer tank 202, so that the diaphragm 202a returns to its original shape. Therefore, even when the resist solution supply source 201 needs to be replaced, the resist solution can be pumped from the buffer tank 202 at a desired pressure.
A switching valve 402 is provided between another buffer tank 401 and the buffer tank 202 in the first processing liquid supply pipe 251.

(Fourth embodiment)
FIG. 17 is an explanatory diagram showing an outline of the configuration of a resist solution supply apparatus according to the fourth embodiment of the present invention.

In the resist solution supply apparatus 500 of FIG. 17, a second processing solution supply pipe 551 is provided below the buffer tank 202 to transfer the resist solution to a pump 211 that is a tube diaphragm pump. In other words, the buffer tank 202 is connected to one end of the second processing liquid supply pipe 551, and one port of the pump 211 (see symbols 202e and 202f in FIG. 8) is connected to the other end.
A filter 212 is provided between the buffer tank 202 and the pump 211 in the second processing liquid supply pipe 551. In the second processing liquid supply pipe 551, a supply valve 214 is provided between the buffer tank 202 and the filter 212, and a switching valve 215 is provided between the supply valve 214 and the filter 212. Further, a switching valve 501 is provided between the filter 212 and the pump 211 in the second processing liquid supply pipe 551.

  The resist solution supply apparatus 500 includes a third processing solution supply pipe 552 that supplies the resist solution from the pump 211 onto the wafer via the coating nozzle 142. One end of the third processing liquid supply pipe 552 is connected between the filter 212 and the switching valve 501 in the second processing liquid supply pipe 551, and the application nozzle 142 is connected to the other end. The third processing liquid supply pipe 552 is provided with a pressure sensor 219, a liquid flow meter 502, a supply control valve 221, and a coating nozzle 142 in order from the upstream side.

Further, the resist solution supply apparatus 500 includes a return pipe 553 used when returning the resist solution in the pump 211 to the buffer tank 202. One end of the return pipe 553 is connected between the supply valve 214 and the switching valve 215 in the second processing liquid supply pipe 551, and the other end is connected to the connection side of the pump 211 with the second processing liquid supply pipe 551. It is connected to the other port on the opposite side (see symbols 202e and 202f in FIG. 8). The return pipe 553 is provided with a switching valve 503.
In the resist solution supply apparatus 500, a gas flow meter 504 is provided in a supply / exhaust pipe 259 provided between the pump 211 and the electropneumatic regulator 216.

  Next, the operation of the resist solution supply apparatus 500 will be described with reference to FIGS.

(Replenishment to the pump 211)
First, as shown in FIG. 18, the supply valve 214, the changeover valve 501, and the changeover valve 501 provided in the second treatment liquid supply pipe 551 and the changeover valve 503 provided in the return pipe 553 are closed. 215 is opened, and the supply control valve 221 is opened. In this state, the resist solution is sent out from the buffer tank 202. Then, the liquid pressure in the third processing liquid supply pipe 552 at this time is measured by the pressure sensor 219. The measured fluid pressure is substantially equal to the back pressure applied to the pump 211 when the resist solution is supplied / supplemented from the buffer tank 202.

  Next, as shown in FIG. 19, the switching valve 215 is closed, the sending of the resist solution from the buffer tank 202 is stopped, and the switching valve 501 is opened. Then, the pressure of the working chamber in the pump 211 is controlled by the electropneumatic regulator 216, and the pressure measured by the pressure sensor 219, that is, the pressure on the switching valve 501 side of the pump 211 is changed when the resist solution is sent from the buffer tank 202. The pressure is made equal to the pressure measured by the pressure sensor 219.

  Thereafter, as shown in FIG. 20, the supply control valve 221 is closed, the switching valve 215 is opened, and replenishment of the resist solution from the buffer tank 202 is started. At this time, the pressure on the switching valve 501 side of the pump 211 is made equal to the pressure measured by the pressure sensor 219 when the resist solution is sent from the buffer tank 202, that is, the back pressure applied to the pump 211 when the resist solution is replenished from the buffer tank 202. Therefore, the resist solution does not instantaneously flow into the pump 211 due to fluctuations in the back pressure at the start of replenishment.

(Other examples of replenishment to the pump 211)
First, as shown in FIG. 18, the supply valve 214, the changeover valve 501, and the changeover valve 501 provided in the second treatment liquid supply pipe 551 and the changeover valve 503 provided in the return pipe 553 are closed. 215 is opened, and the supply control valve 221 is opened. In this state, the resist solution is sent out from the buffer tank 202. The pressure sensor 219 measures the pressure on the secondary side of the filter 212, specifically, the liquid pressure in the third processing liquid supply pipe 552. Simultaneously with this pressure measurement, the pressure of the working chamber in the buffer tank 202 is controlled by the electropneumatic regulator 207, and feedback control is performed so that the pressure measured by the pressure sensor 219 becomes a target pressure (for example, 50 kPa).

  Next, as shown in FIG. 21, the supply valve 214 is closed and the switching valve 501 is opened. Then, the pressure of the working chamber in the pump 211 is controlled by the electropneumatic regulator 216 so that the pressure measured by the pressure sensor 219, that is, the pressure on the switching valve 501 side of the pump 211 becomes equal to the target pressure as described above. To.

  Thereafter, as shown in FIG. 20, the supply control valve 221 is closed, the supply valve 214 is opened, and replenishment of the resist solution from the buffer tank 202 is started. In this case, at the start of replenishment, the pressure of the pumped liquid from the buffer tank 202 and the pressure on the switching valve 501 side of the pump 211 are equal to the target pressure. The resist solution does not flow into.

(vomit)
When discharging the resist solution, as shown in FIG. 22, a switching valve 501 provided in the second processing liquid supply pipe 551 and a supply control valve 221 provided in the third processing liquid supply pipe 552 are provided. Open. At the same time, the electropneumatic regulator 216 sets the connection destination of the pump 211 as the pressurizing source 217, and supplies the third processing liquid via the second processing liquid supply pipe 551 from the port on the switching valve 501 side of the pump 211. Pump to tube 552. As a result, the resist solution passed through the filter 212 and stored in the pump 211 is discharged onto the wafer through the coating nozzle 142.

(Other examples of discharge)
As shown in FIG. 23, the switching valve 215 provided in the second processing liquid supply pipe 551, the supply control valve 221 provided in the third processing liquid supply pipe 552, and the return pipe 553 are provided. The switched valve 503 is opened. At the same time, the electropneumatic regulator 216 sets the connection destination of the pump 211 as the pressure source 217, and the resist solution is supplied from the port on the return pipe 553 side of the pump 211 through the return pipe 553 and the second processing liquid supply pipe 551. To the processing liquid supply pipe 552. As a result, the resist solution passed through the filter 212 and stored in the pump 211 can be discharged to the wafer after passing through the filter 212 again. By configuring in this way, the possibility of defects occurring in the wafer can be further reduced.

(Discharge switching)
In the following, the method of discharging the resist solution to the wafer after passing it again through the filter 212 as shown in FIG. 23 is the double pass method, and the method of discharging the resist solution to the wafer without passing it again through the filter 212 as shown in FIG. It is called a method.
The double pass method and the single pass method are preferably selectable depending on the purpose. For example, the double pass method is usually used, and the single pass method is used when purging or when it is necessary to discharge the resist solution in a short time.

  The resist solution replenishment rate to the pump 211, that is, the filtration rate of the filter 212 at the time of replenishment, and the discharge rate of the resist solution in the double-pass method, that is, the filtration rate of the filter 212 at the time of discharge in this method are both filtration rates. Both are preferably slow. This is because the slower one can collect the particles in the processing liquid more reliably by the filter 212. However, if the latter filtration rate is too slow, the processing liquid is intermittently ejected in the form of droplets, so there is a limit to speed reduction. Therefore, it is preferable that the filtration rate at the time of replenishment is smaller than the filtration rate at the time of replenishment and the filtration rate at the time of discharge. The filtration rate at the time of replenishment is, for example, 0.05 ml / second, and the filtration rate at the time of discharge is, for example, 0.5 ml / second.

(Bento)
When venting, for example, as shown in FIG. 24, first, the supply valve 214 provided in the second treatment liquid supply pipe 551 and the switching valve 503 provided in the return pipe 553 are kept closed. The switching valve 215 and the supply control valve 221 are opened, and the discharge valve 213 is opened. Then, the liquid pressure in the third processing liquid supply pipe 552 at this time is measured by the pressure sensor 219. The measured fluid pressure is approximately equal to the back pressure applied to the pump 211 during venting.

  Next, as shown in FIG. 25, the discharge valve 213 and the supply control valve 221 are closed, and the switching valve 503 is opened. Then, the pressure of the working chamber in the pump 211 is controlled by the electropneumatic regulator 216, and the pressure measured by the pressure sensor 219, that is, the pressure on the switching valve 503 side of the pump 211 is measured by the pressure sensor 219 in the state of FIG. To be equal to the applied pressure.

  Thereafter, as shown in FIG. 26, the discharge valve 213 is opened, and the discharge of the resist solution in the pump 211 via the drain pipe 258 is started. At this time, the pressure on the switching valve 503 side of the pump 211 is equal to the pressure measured by the pressure sensor 219 in the state of FIG. 24, that is, the back pressure applied to the pump 211 at the time of venting. Due to the fluctuation, the resist solution does not flow into the pump 211 instantaneously.

(Other examples of vents)
As a venting method, there is a return venting method for returning to the buffer tank 202 in addition to the filter venting method for discharging through the filter 212 described above.
In the return vent method, before venting, for example, as shown in FIG. 18, first, the switching valve 501 and the switching valve 503 are closed, and the supply valve 214, the switching valve 215, and the supply control valve 221 are opened. To do. In this state, the resist solution is sent out from the buffer tank 202. The pressure sensor 219 measures the pressure on the secondary side of the filter 212, specifically, the liquid pressure in the third processing liquid supply pipe 552. Along with this pressure measurement, the electropneumatic regulator 207 controls the pressure in the working chamber in the buffer tank 202, and feedback control is performed so that the pressure measured by the pressure sensor 219 becomes a predetermined pressure. Next, the pressure at the start of venting of the pump 211 is corrected based on the pressure in the working chamber of the buffer tank 202 when the pressure measured by the pressure sensor 219 becomes a predetermined pressure. For example, if the pressure in the working chamber at a predetermined pressure is large, the pressure at the start of venting of the pump 211 is corrected to be high, and if small, the pressure is corrected to be small.

  Next, as shown in FIG. 25, the supply valve 214 and the supply control valve 221 are closed, and the switching valve 503 is opened. Then, the pressure of the working chamber in the pump 211 is controlled by the electropneumatic regulator 216, and the pressure measured by the pressure sensor 219, that is, the pressure on the switching valve 503 side of the pump 211 is corrected. Make pressure.

Thereafter, as shown in FIG. 27, the supply valve 214 is opened, the switching valve 215 is closed,
The resist solution in the pump 211 is returned to the buffer tank 202, that is, return venting is started.
Since the pressure in the storage chamber of the buffer tank 202 varies depending on the amount of the resist solution in the storage chamber, if the pressure of the pump 211 at the start of the return vent is constant, the return vent cannot be performed properly. However, in this example, since the pressure of the pump 211 at the start of the return vent is corrected based on the pressure in the working chamber of the buffer tank 202 corresponding to the pressure in the storage chamber of the buffer tank 202, the return vent is appropriately controlled. It can be carried out.

(Vent amount)
The vent amount is determined by the difference between the replenishment amount to the pump 211 and the discharge amount of the resist solution.
In the example shown in the figure, since the liquid flow meter 502 is provided, the actual discharge amount of the resist solution can be calculated based on the measurement result of the liquid flow meter 502. Therefore, the vent amount can be accurately calculated.
When the liquid flow meter 502 is not provided, the flow rate of the gas sent to the pump 211 is measured by the gas flow meter 504 provided for the pump 211, and is calculated using the measurement result. The gas flow meter 504 is a mass flow meter, and can calculate the discharge amount of the resist solution by converting the integrated value of the measured mass into a volume. Since the relationship between mass and volume depends on pressure and temperature, conversion from mass to volume may be performed assuming that the temperature in the pump 211 is 20 ° C. and the pressure in the pump 211 is 1 atm. However, it may be performed based on the pressure of the working chamber of the pump 211 measured when the temperature in the pump 211 is 23 ° C.
By determining the vent amount accurately, the vent time can be set appropriately.

(Vent execution timing)
The return vent is performed to prevent the resist solution from staying, and is performed periodically, for example.
The filter vent is performed when the cleaning degree of the resist solution in the pump 211 or the like is low. For example, the filter vent is performed at the time of start-up or periodically, or bubbles are detected on the primary side of the filter 212. Sometimes done.
The bubble detector is preferably provided, for example, in a portion between the connection portion of the return pipe 553 and the supply valve 214 in the second processing liquid supply pipe 551. In the actual resist solution supply apparatus 500, this portion is located above the filter 212 and the pump 211 in the vertical direction. Therefore, more specifically, bubbles generated on the primary side of the filter, more specifically, bubbles generated in the system path from the part where the filter 212, the pump 211, and the bubble detector are provided to the filter 212 and the pump 211 are reliably Can be detected.

(Abnormality detection)
In the resist solution supply apparatus 500, the diaphragm constituting the storage chamber of the pump 211 extends with time, so that the pressure for deforming the diaphragm, that is, the pressure (EV pressure) of the working chamber in the pump 211 controlled by the electropneumatic regulator 216 is obtained. Needs to be increased to match the elongation of the diaphragm.
Therefore, the resist solution supply apparatus 500 measures the EV pressure and compares it with the pressure (fluid pressure) measured by the pressure sensor 219. If the expansion of the diaphragm exceeds an allowable range or other abnormality occurs and the difference between the EV pressure and the hydraulic pressure exceeds a predetermined value, an error is notified by sound information or visual information.
In addition to the error notification, pressurization of the working chamber of the pump 211 by the pressurization source 217 is stopped, and the EV pressure is set to atmospheric pressure. At that time, the supply valve 214, the switching valve 215, and the switching valve 501 are preferably opened.
Similarly to the pump 211, the buffer tank 202 may detect an error based on the pressure in the working chamber in the buffer tank.

  In the above resist solution supply apparatus 500, the liquid flow meter 502 is provided between the pump 211 and the supply control valve 221 in the third process liquid supply pipe 552, but the second process liquid supply pipe is not provided. You may provide between the connection part of the 3rd process liquid supply pipe | tube 552 in 551, and the filter 212. FIG. Further, the liquid flow meter 502 may not be provided.

  In the resist solution supply apparatus 500, a pressure sensor 219 that measures the pressure on the secondary side of the filter 212 is provided at the most upstream portion of the third processing solution supply pipe 552. However, the pressure sensor 219 may be provided between the connection portion of the third processing liquid supply pipe 552 and the switching valve 501 in the second processing liquid supply pipe 551. In this case, when the resist solution is discharged from the pump 211 via the filter 212, the pressure sensor 219 is not passed, so that particles can be further prevented from being mixed into the resist solution.

In addition to the pressure sensor 219 that measures the pressure on the secondary side of the filter 212, the resist solution supply apparatus 500 may be provided with a pressure sensor that measures the pressure on the primary side of the filter 212.
The primary-side pressure sensor is provided, for example, in a portion between the switching valve 215 and the filter 212 in the second processing liquid supply pipe 551. The differential pressure between the primary side pressure sensor and the secondary side pressure sensor 219 provided in the portion varies depending on the clogged state of the filter 212. Therefore, by providing the primary side pressure sensor 219 in the above portion, the state of the filter 212 can be determined based on the differential pressure.
When the primary pressure sensor is provided in the above-described portion, the pressure loss from the buffer tank 202 to the primary pressure sensor is smaller than the pressure loss from the buffer tank 202 to the secondary pressure sensor 219. Therefore, if the measurement result of the primary pressure sensor is fed back to the pressure in the working chamber of the buffer tank 202, the measurement result in the buffer tank 202 is compared to the case where the measurement result of the secondary pressure sensor 219 is fed back. The pressure applied to the resist solution can be made more desirable.
In the resist solution supply apparatus 500, even if the primary pressure sensor is provided between the buffer tank 202 and the supply valve 214 in the second processing solution supply pipe 551, as described above, the switching valve 215 and the filter are used. The same effect as that provided in the portion between the two is obtained.

  The resist solution supply apparatus 500 can generate a degassed solution using the buffer tank 202. By passing the degassed liquid generated in the buffer tank 202 through the filter 212 at the time of starting up the filter 212 or during regular maintenance, fine bubbles that cannot be removed by a normal resist liquid that has not been degassed are removed. be able to. The degassed liquid passed through the filter 212 is preferably discharged through the drain pipe 258.

  In the above description, the resist liquid is described as an example of the processing liquid supplied by the processing liquid supply apparatus according to the present invention. However, for example, a coating liquid of SOG (Spin On Glass) may be supplied.

  FIG. 28 is a diagram showing the amount of particles observed in the resist films of Examples and Comparative Examples. FIGS. 28A to 28D are, in order, Comparative Example 1, Example 1, Comparative Example 2, and Example. The amount of particles in Example 2 is shown. In the figure, the horizontal axis indicates the number of wafers, the vertical axis indicates the amount of particles, and the number of particles present in the resist film of the fourth wafer in Comparative Example 2 is shown. The value when 1 is shown. The presence / absence / number of particles was confirmed by observation with an electron microscope. In addition, the shaded portion in the bar graph in the figure indicates the number of particles that are considered to be caused by bubbles.

In Example 1 and Example 2, using the resist solution supply apparatus 500 according to the fourth embodiment, while pressurizing with the buffer tank 202 so that the pressure at the pressure sensor 219 is 50 kPa, specifically, The resist solution was replenished to the pump 211 from the buffer tank 202 while controlling the pressure in the working chamber of the buffer tank 202 so that the pressure at the pressure sensor 219 was 50 kPa. In Examples 1 and 2, the resist solution was supplied from the pump 211 by the double pass method to form a resist film.
In Comparative Example 1 and Comparative Example 2, using the resist solution supply apparatus 500 according to the fourth embodiment, the resist solution is replenished from the buffer tank 202 to the pump 211, and the resist solution is supplied from the pump 211 by a double pass method. Although a resist film was formed, no pressure was applied by the buffer tank 202 during replenishment.
Further, Example 1 and Comparative Example 1, Example 2 and Comparative Example 2 differ in the positional relationship between the buffer tank and the filter, the piping between them, the installation location of the processing liquid supply device, and the like.

As shown in FIG. 28 (A) and FIG. 28 (C), although there are few in Comparative Example 1, there are many particles in Comparative Example 1 and Comparative Example 2, and there are also particles that are thought to be caused by bubbles. To do.
On the other hand, in Example 1 and Example 2, as shown in FIGS. 28B and 28D, the number of particles is small, and in particular, the number of particles considered to be caused by bubbles is zero.

  As can be seen from the above-described examples and comparative examples, according to the resist solution supply apparatus 500, even if the buffer tank 202 does not have a pressurizing function, the filter 212 can remove particles even in an environment where many particles exist. Can be removed appropriately. That is, particles can be removed appropriately regardless of the environment. Further, according to the resist solution supply apparatus 500, it is possible to prevent generation of particles due to bubbles regardless of the environment.

  The present invention is useful for a technique for applying a treatment liquid to an object to be treated.

142: coating nozzle 200, 300, 400, 500 ... resist solution supply device 201 ... resist solution supply source 202 ... buffer tank 202a ... diaphragm 202b ... storage chamber 207 ... electro-pneumatic regulator 210 ... pressure sensor 211 ... pump 212 ... filter 216 ... Electropneumatic regulator 219 ... Pressure sensor 223 ... Pressure sensor

Claims (11)

A processing liquid supply device that supplies a processing liquid to a processing liquid discharge unit that discharges the processing liquid to a target object,
A temporary storage device for temporarily storing a processing liquid supplied from a processing liquid supply source for storing the processing liquid;
A filter for removing foreign matter in the processing liquid from the temporary storage device;
A pump for delivering the processing liquid from which foreign matter has been removed by the filter to the processing liquid discharge section,
The said temporary storage apparatus has a pumping function which pumps the processing liquid currently stored in this temporary storage apparatus, The processing liquid supply apparatus characterized by the above-mentioned. A pressure measuring device that is provided downstream of the temporary storage device and measures the liquid pressure of the processing liquid;
The processing liquid supply apparatus according to claim 1, further comprising: a control device that controls at least pumping of the processing liquid from the temporary storage device based on a measurement result of the pressure measuring device. The pressure measuring device measures a hydraulic pressure on the secondary side of the filter,
The processing liquid supply apparatus according to claim 2, wherein the control device controls a liquid pressure at the time of the pressure feeding so that a liquid pressure on a secondary side of the filter is constant. The pressure measuring device measures a hydraulic pressure on the secondary side of the filter,
3. The control device according to claim 2, wherein when the fluid pressure on the secondary side of the filter is within a predetermined range, the control device applies a predetermined pressure to the temporary storage device to pump the processing liquid. Treatment liquid supply device. The pressure measuring device measures the hydraulic pressure on the primary side of the filter;
The processing liquid supply apparatus according to claim 2, wherein the control apparatus controls a liquid pressure at the time of the pressure feeding so that a liquid pressure on a primary side of the filter is constant. A plurality of sets of the temporary storage device, the filter and the pump;
The said control apparatus has an electropneumatic regulator provided with respect to each said temporary storage apparatus which adjusts the hydraulic pressure in the storage chamber which stores the process liquid of the said temporary storage apparatus. The processing liquid supply apparatus according to any one of the above.   The processing liquid supply apparatus according to claim 1, wherein the temporary storage device is a tube diaphragm pump. A plurality of sets of the temporary storage device, the filter and the pump;
Each of the temporary storage devices has a separate storage device for storing the processing liquid and another pump for pumping the processing liquid in the storage device,
For the other pump of the temporary storage device, a common electropneumatic regulator for adjusting the fluid pressure in the storage chamber for storing the processing liquid of the other pump is provided,
2. The processing liquid supply apparatus according to claim 1, wherein the control of the liquid pressure during the pumping of the processing liquid from the temporary storage apparatus is performed by the electropneumatic regulator.   The processing liquid supply apparatus according to claim 8, wherein the another pump is a tube diaphragm pump.   10. The pump according to claim 1, wherein when the processing liquid from which foreign matters have been removed by the filter is sent to the processing liquid discharge unit, the pump is sent so as to pass through the filter again. The processing liquid supply apparatus described in 1. In order from the upstream side, the temporary storage device, the filter and the treatment liquid supply pipe provided with the pump,
The pump has a storage chamber for storing the processing liquid,
The treatment liquid supply pipe has one valve between the temporary storage device and the filter, and another valve between the temporary storage device and the filter,
The control device opens the one valve and closes the other valve when replenishing the processing liquid from which foreign substances have been removed by the filter from the temporary storage device to the storage chamber of the pump. The pressure of the treatment liquid from the temporary storage device is controlled so that the pressure on the secondary side of the filter measured by the measuring device becomes a predetermined value, and then the one valve is closed and the other valve is closed. In the opened state, after controlling the pressure in the storage chamber so that the pressure on the secondary side of the filter measured by the pressure measuring device becomes the predetermined value, the one valve and the other valve The processing liquid supply apparatus according to claim 2, wherein the replenishment is started in a state in which the liquid is opened.

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