Processing liquid supply device and assist pump

Abstract

To provide a technology for preventing bubbles from forming on a processing object and causing defects in a processing liquid supply device that supplies a processing liquid to the processing object.SOLUTION: A processing liquid supply device includes a processing liquid supply source 50 that stores processing liquid, a pressurizing mechanism that pressurizes the processing liquid in the processing liquid supply source 50 with an inert gas, and a processing liquid flow path that is a flow path for the processing liquid from the processing liquid supply source 50. The processing liquid supply device also includes a nozzle 41 that ejects the processing liquid supplied through the processing liquid flow path onto a workpiece W, and a control device 100 that controls the operation of the pressurizing mechanism. When the state of the processing liquid near the nozzle 41 in the processing liquid flow path satisfies predetermined bubble generation conditions for bubble generation, the control device 100 controls the pressurizing mechanism such that the pressurizing force of the inert gas is smaller than a predetermined normal value.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a treatment liquid supply device and an assist pump. [Background technology]

[0002] Patent Document 1 discloses a processing liquid supply system in which an open / close valve and a suck-back valve are provided in a processing liquid supply flow path that connects a processing liquid supply source and a processing liquid supply nozzle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-171295 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technology for suppressing defects caused by bubbles on a processing object in a processing liquid supply device that supplies a processing liquid to a processing object. [Means for solving the problem]

[0005] A processing liquid supply device according to one aspect of the present disclosure includes a processing liquid supply source that stores a processing liquid, a pressurizing mechanism that pressurizes the processing liquid in the processing liquid supply source with an inert gas, and a processing liquid flow path through which the processing liquid is passed from the processing liquid supply source. The processing liquid supply device according to one aspect of the present disclosure also includes a nozzle that ejects the processing liquid supplied through the processing liquid flow path onto a processing target object, and a control unit that controls the operation of the pressurizing mechanism. When the state of the processing liquid near the nozzle in the processing liquid flow path satisfies a predetermined bubble generation condition, the control unit controls the pressurizing mechanism so that the pressurizing force of the inert gas is smaller than a predetermined normal value. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to provide a technology for suppressing defects caused by bubbles on a processing object in a processing liquid supplying device that supplies a processing liquid to a processing object. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram showing an example of a schematic configuration of a substrate processing system. [Figure 2] FIG. 2 is a schematic diagram showing an example of the internal configuration of a coating and developing apparatus. [Figure 3] FIG. 3 is a schematic diagram showing an example of the configuration of the liquid processing unit. [Figure 4] FIG. 4 is a schematic diagram showing an example of a processing liquid supply unit. [Figure 5] FIG. 5 is a table showing the experimental conditions for investigating the foaming mechanism. [Figure 6] FIG. 6 is a table showing the visual observation results of the foaming state in the experiment to investigate the foaming mechanism. [Figure 7] FIG. 7 is a graph showing the measurement results of the negative pressure integrated value in the experiment for investigating the foaming mechanism. [Figure 8] FIG. 8 is a schematic diagram showing an example of the bubble detection unit. [Figure 9] FIG. 9 is a diagram illustrating the position of the processing liquid supply source. [Figure 10] FIG. 10 is a diagram illustrating a mode in which the internal pressure of the assist pump is reduced in stages. [Figure 11] FIG. 11 is a block diagram illustrating an example of a hardware configuration of the control device. [Figure 12] FIG. 12 is a schematic diagram showing a processing liquid supply unit according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, the embodiments will be described in detail with reference to the drawings. In the description, the same elements or elements having the same functions are denoted by the same reference numerals, and redundant description will be omitted.

[0009] [Substrate processing system] The substrate processing system 1 shown in FIG. 1 is a system that forms a photosensitive coating on a substrate, exposes the photosensitive coating, and develops the photosensitive coating. The workpiece W (substrate) to be processed is, for example, a semiconductor substrate. One example of a substrate is a silicon wafer. The workpiece W may be formed in a circular shape. The workpiece W to be processed may also be a glass substrate, a mask substrate, an FPD (Flat Panel Display), or the like. The workpiece W may have a cutout portion cut out of a portion. The cutout portion may be, for example, a notch (a U-shaped, V-shaped, or other groove) or a linear portion extending in a straight line (a so-called orientation flat). The photosensitive coating is, for example, a resist film.

[0010] The substrate processing system 1 includes a coating / developing apparatus 2 and an exposure apparatus 3. The exposure apparatus 3 performs an exposure process on a resist film (photosensitive coating) formed on a workpiece W (substrate). Specifically, it irradiates an energy beam onto the portion of the resist film to be exposed by a method such as immersion exposure. The coating / developing apparatus 2 performs a process of forming a resist film on the surface of the workpiece W (substrate) before the exposure process by the exposure apparatus 3, and then performs a development process on the resist film after the exposure process.

[0011] [Substrate processing equipment] The following describes the configuration of a coating and developing apparatus 2 as an example of a substrate processing apparatus. As shown in Figures 1 and 2, the coating and developing apparatus 2 includes a carrier block 4, a processing block 5, an interface block 6, and a control device 100.

[0012] The carrier block 4 introduces the workpiece W into the coating and developing device 2 and removes the workpiece W from the coating and developing device 2. For example, the carrier block 4 can support multiple carriers C for the workpiece W and has a built-in transport device A1 including a transfer arm. The carrier C accommodates, for example, multiple circular workpieces W. The transport device A1 removes the workpiece W from the carrier C and passes it to the processing block 5, and receives the workpiece W from the processing block 5 and returns it to the carrier C.

[0013] The processing block 5 has a plurality of processing modules 11, 12, 13, and 14. Each of the processing modules 11, 12, 13, and 14 incorporates a liquid processing unit U1, a heat processing unit U2, and a transfer device A3 including a transfer arm for transferring the workpiece W to these units.

[0014] The processing module 11 uses a liquid processing unit U1 and a heat processing unit U2 to form an underlayer film on the surface of the workpiece W. The liquid processing unit U1 of the processing module 11 applies a processing liquid for forming the underlayer film onto the workpiece W. The heat processing unit U2 of the processing module 11 performs various heat treatments associated with the formation of the underlayer film.

[0015] The processing module 12 forms a resist film on the underlying film using a liquid processing unit U1 and a thermal processing unit U2. The liquid processing unit U1 of the processing module 12 applies a processing liquid for forming the resist film onto the underlying film. The thermal processing unit U2 of the processing module 12 performs various thermal processes associated with the formation of the resist film.

[0016] The processing module 13 forms an upper layer film on the resist film using a liquid processing unit U1 and a thermal processing unit U2. The liquid processing unit U1 of the processing module 13 applies a liquid for forming the upper layer film onto the resist film. The thermal processing unit U2 of the processing module 13 performs various thermal processes associated with the formation of the upper layer film.

[0017] The processing module 14 uses a liquid processing unit U1 and a thermal processing unit U2 to perform development processing on the exposed resist film. The liquid processing unit U1 applies a developer to the surface of the exposed workpiece W. The liquid processing unit U1 also washes away the applied developer with a rinse liquid. The thermal processing unit U2 performs various thermal processes associated with the development processing. Specific examples of thermal processing include a post-exposure bake (PEB) before the development processing and a post-exposure bake (PB) after the development processing.

[0018] A shelf unit U10 is provided on the carrier block 4 side within the processing block 5. The shelf unit U10 is divided into multiple cells arranged in the vertical direction. A transport device A7 including a lifting arm is provided near the shelf unit U10. The transport device A7 raises and lowers the workpiece W between the cells of the shelf unit U10.

[0019] A shelf unit U11 is provided on the interface block 6 side in the processing block 5. The shelf unit U11 is divided into a plurality of cells arranged in the vertical direction.

[0020] The interface block 6 transfers the workpiece W to and from the exposure apparatus 3. For example, the interface block 6 has a built-in transport device A8 including a transfer arm, and is connected to the exposure apparatus 3. The transport device A8 transfers the workpiece W placed on the shelf unit U11 to the exposure apparatus 3. The transport device A8 receives the workpiece W from the exposure apparatus 3 and returns it to the shelf unit U11.

[0021] The control device 100 controls the coating and developing device 2 to perform the coating and developing process, for example, in the following procedure: First, the control device 100 controls the transport device A1 to transport the workpiece W in the carrier C to the shelf unit U10, and then controls the transport device A7 to place the workpiece W in a cell for the processing module 11.

[0022] Next, the control device 100 controls the transport device A3 to transport the workpiece W on the shelf unit U10 to the liquid processing unit U1 and the heat processing unit U2 in the processing module 11. The control device 100 also controls the liquid processing unit U1 and the heat processing unit U2 to form an underlayer film on the surface of the workpiece W. Thereafter, the control device 100 controls the transport device A3 to return the workpiece W on which the underlayer film has been formed to the shelf unit U10, and controls the transport device A7 to place the workpiece W in a cell for the processing module 12.

[0023] Next, the control device 100 controls the transport device A3 to transport the workpiece W from the shelf unit U10 to the liquid processing unit U1 and the heat processing unit U2 in the processing module 12. The control device 100 also controls the liquid processing unit U1 and the heat processing unit U2 to form a resist film on the underlying film of the workpiece W. Thereafter, the control device 100 controls the transport device A3 to return the workpiece W to the shelf unit U10, and controls the transport device A7 to place the workpiece W in a cell for the processing module 13.

[0024] Next, the control device 100 controls the transport device A3 to transport the workpiece W on the shelf unit U10 to each unit in the processing module 13. The control device 100 also controls the liquid processing unit U1 and the heat processing unit U2 to form an upper layer film on the resist film of the workpiece W. Thereafter, the control device 100 controls the transport device A3 to transport the workpiece W to the shelf unit U11.

[0025] Next, the control device 100 controls the transport device A8 to send the workpiece W on the shelf unit U11 to the exposure device 3. Thereafter, the control device 100 controls the transport device A8 to receive the workpiece W that has been subjected to the exposure process from the exposure device 3 and place it in a cell for the processing module 14 in the shelf unit U11.

[0026] Next, the control device 100 controls the transport device A3 to transport the workpiece W on the shelf unit U11 to each unit in the processing module 14, and controls the liquid processing unit U1 and the heat processing unit U2 to perform a development process on the resist film on the workpiece W. Thereafter, the control device 100 controls the transport device A3 to return the workpiece W to the shelf unit U10, and controls the transport devices A7 and A1 to return the workpiece W into the carrier C. This completes the coating and developing process.

[0027] The specific configuration of the substrate processing apparatus is not limited to the configuration of the coating and developing apparatus 2 exemplified above. The substrate processing apparatus may be any type as long as it includes a liquid processing unit that performs liquid processing by discharging a processing liquid onto the workpiece W, and a control device that can control the liquid processing unit.

[0028] [Liquid processing unit] 3 and 4, an example of the liquid processing unit U1 in the processing module 12 will be described in detail. The liquid processing unit U1 includes a spin holder 20 and a processing liquid supply unit 30. The liquid processing unit U1 and a control device 100 (controller) that controls the liquid processing unit U1 have a configuration corresponding to the processing liquid supply device of this embodiment.

[0029] The rotating holding unit 20 holds and rotates the workpiece W based on operational instructions from the control device 100. The rotating holding unit 20 includes a holding unit 21 and a drive unit 22. The holding unit 21 supports the center of the workpiece W, which is placed horizontally with its surface Wa facing upward, and holds the workpiece W by suction (e.g., vacuum suction) or the like. The drive unit 22 is a rotation actuator powered by, for example, an electric motor or the like, and rotates the holding unit 21 around a vertical rotation axis. This causes the workpiece W to rotate around the vertical rotation axis.

[0030] The processing liquid supply unit 30 supplies the processing liquid to the workpiece W rotatably held by the rotation holder 20. As shown in FIGS. 3 and 4, the processing liquid supply unit 30 includes a discharge unit 40, a processing liquid supply source 50, and a liquid delivery system 60. The liquid delivery system 60 includes a flow path for supplying the processing liquid, and pumps, valves, and the like for delivering the liquid through the flow path. Furthermore, the liquid delivery system 60 also includes a gas supply system 80 for supplying an inert gas that can be used to adjust the delivery of the liquid.

[0031] The discharge unit 40 discharges the processing liquid toward the surface Wa of the workpiece W. The discharge unit 40 includes a nozzle 41 and a liquid supply pipe 42. The nozzle 41 discharges the processing liquid toward the workpiece W, which is the object to be processed. As shown in FIG. 3 , the nozzle 41 is, for example, disposed above the workpiece W, and discharges the processing liquid supplied via the liquid supply pipe 42 onto the workpiece W below. The liquid supply pipe 42 guides the processing liquid to the nozzle 41. The liquid supply pipe 42 is included in a processing liquid flow path, which is a flow path for the processing liquid from the processing liquid supply source 50, and is the most downstream flow path of the processing liquid flow path. The processing liquid is applied (supplied) to the workpiece W by being discharged from the nozzle 41 toward the workpiece W.

[0032] 4, the processing liquid is supplied from a processing liquid supply source 50. The processing liquid supply source 50 is a tank that stores the processing liquid, and is detachable from the liquid delivery system 60. When cleaning the liquid delivery system 60, a cleaning liquid supply source that stores the cleaning liquid can be installed in the same location instead of the processing liquid supply source 50.

[0033] The processing liquid supply source 50 is connected to a gas supply source 81 that supplies an inert gas such as nitrogen (N2) via a gas supply path R81 provided with a valve V81. The gas supply source 81, the gas supply path R81, and the valve V81 are components included in a gas supply system 80, and constitute a pressurizing mechanism that pressurizes the liquid surface of the processing liquid in the processing liquid supply source 50 with the inert gas, thereby moving the processing liquid from the processing liquid supply source 50. In addition, the gas supply path R81 may be provided with a separate exhaust path R85 for exhausting the inert gas.

[0034] The flow path L1 connected to the processing liquid supply source 50 is provided with a liquid delivery system 60, which is provided, in this order from the upstream side, with an intermediate tank 61, an assist pump 62 (second pump), a pump flow path system 70, and a dispense valve V2. The dispense valve V2 has a function of discharging a preset amount of processing liquid. The flow path L1 is configured to be included in a processing liquid flow path, which is a flow path for the processing liquid from the processing liquid supply source 50. In other words, the processing liquid flow path is configured by the flow path L1 and the liquid delivery pipe 42.

[0035] The intermediate tank 61 is disposed upstream of the assist pump 62 in the flow path L1. The intermediate tank 61 stores the processing liquid supplied from the processing liquid supply source 50 and sends the processing liquid downstream. The flow path L1 from the processing liquid supply source 50 is connected to the upper surface of the intermediate tank 61, and the flow path L1 to the downstream assist pump 62 is connected to the lower surface of the intermediate tank 61. The intermediate tank 61 may have, for example, a storage chamber for storing the processing liquid and may function as a pump having a contraction portion for contracting the storage chamber. In this case, the intermediate tank 61 may be, for example, a tube phragm pump, a diaphragm pump, or a bellows pump. The intermediate tank 61 may be provided with an exhaust pipe 61a for discharging gas therein. The exhaust pipe 61a may be used, for example, during a vent process for discharging gas separated from the processing liquid in the storage chamber.

[0036] The assist pump 62, located upstream of the pump flow path system 70, functions to deliver liquid to the pump flow path system 70. The assist pump 62 is provided with a liquid supply valve V61 and a liquid discharge valve (not shown). The assist pump 62 is, for example, a diaphragm pump. The assist pump 62 includes a pressurizing unit and a pump internal flow path. The pressurizing unit pressurizes the pump internal flow path using, for example, compressed air. The pump internal flow path has a diaphragm, the shape of which can be forcibly changed by pressurizing the pump internal flow path with the pressurizing unit. The diaphragm of the pump internal flow path is deformed by adjusting the compressed air. In this way, the assist pump 62 changes the size (volume) of the pump internal flow path by changing the degree of pressurization applied to the pump internal flow path by the pressurizing unit. That is, when the pressurization unit applies a small amount of pressure, the diaphragm of the pump internal flow path expands to receive the processing liquid, and when the pressurization unit applies a large amount of pressure, the diaphragm of the pump internal flow path contracts to discharge the processing liquid. The pressure applied when receiving (replenishing) the processing liquid may be referred to as vacuum pressure below.

[0037] The assist pump 62 may be configured to set a first vacuum pressure and a second vacuum pressure higher than the first vacuum pressure as the vacuum pressure when replenishing the processing liquid to be sent toward the pump flow path system 70. The assist pump 62 may replenish the processing liquid after a predetermined pre-depressurization time has elapsed. The vacuum pressure in the pre-depressurization and the vacuum pressure during replenishment may be different from each other. The assist pump 62 may be configured to set a third vacuum pressure higher than the first vacuum pressure but lower than the second vacuum pressure as the vacuum pressure when replenishing the processing liquid, and the pre-depressurization may be performed using the third vacuum pressure (details will be described later). In this way, the assist pump 62 may increase the vacuum pressure stepwise during the processing liquid replenishment operation in a predetermined case (details will be described later).

[0038] The pump flow path system 70 is configured to supply the processing liquid to the nozzle 41. The pump flow path system 70 includes, in order from the downstream side, a pump 71, a trap unit 72, a filter unit 73, and a valve V70. A filter for removing particles from the processing liquid is attached to the filter unit 73.

[0039] The pump 71 is configured to discharge the processing liquid into the nozzle 41 and is, for example, a diaphragm pump. The pump 71 includes a pressurizing unit and a pump internal flow path. The pressurizing unit pressurizes the pump internal flow path using, for example, compressed air. The pump internal flow path also has a phragm, the shape of which can be forcibly changed by pressurization by the pressurizing unit. The phragm of the pump internal flow path is deformed by adjusting the compressed air. When the pressurization by the pressurizing unit is reduced, the phragm of the pump internal flow path expands to accept the processing liquid, and when the pressurization by the pressurizing unit is increased, the phragm of the pump internal flow path contracts to discharge the processing liquid.

[0040] The pump 71 is also provided with a liquid supply valve V71, a liquid discharge valve V72, and a vent valve V73. The vent valve V73 and trap unit 72 are connected by a flow path L71. A bypass path that bypasses the filter unit 73 and includes a valve V75 is provided between the pump 71 and the upstream side of the valve V70 in the flow path L1 via the trap unit 72. The filter unit 73 and the trap unit 72 are connected to vent valves V78 and V79, respectively.

[0041] Of the valves provided in the liquid delivery system 60, the valves other than the dispense valve V2 may be, for example, air-operated valves, although the configuration of the valves is not limited to this.

[0042] In the above-described configuration of the processing liquid supply device, the generation of bubbles within the system is suppressed by maintaining a positive pressure within the system. However, if the system is maintained at a positive pressure, there is a possibility that bubbles will be generated downstream of the dispense valve V2, which is the point at which the system is opened to the atmosphere, due to the influence of negative pressure. If bubbles are generated downstream of the dispense valve V2, the bubbles will be contained in the processing liquid discharged from the nozzle 41, and may be trapped on the workpiece W, causing defects.

[0043] The inventors conducted experiments to understand the foaming mechanism and investigate the causes of foaming. FIG. 5 is a table showing the conditions of the experiment for investigating the foaming mechanism. FIG. 6 is a table showing the visual observation results of the foaming state in the experiment for investigating the foaming mechanism. FIG. 7 is a graph showing the measurement results of the negative pressure integrated value in the experiment for investigating the foaming mechanism.

[0044] As shown in FIG. 5 , experiments were conducted under four conditions, Condition 1 to Condition 4, based on the configuration of the processing liquid supply device described above. The four conditions differ from one another in the height of the processing liquid supply source 50, the vacuum pressure of the assist pump 62, the pre-depressurization time of the assist pump 62, and the pressurization force of the processing liquid supply source 50. The height of the processing liquid supply source 50 (Bottle Height in FIG. 5 ) is the height relative to the intermediate tank 61 (the upward distance relative to the height of the intermediate tank 61). The vacuum pressure of the assist pump 62 (Assist Vacuum Setting in FIG. 5 ) is the vacuum pressure of the assist pump 62 when receiving (replenishing) the processing liquid. The pre-depressurization time of the assist pump 62 (Prior Depressurization Time in FIG. 5 ) is the time during which vacuum pressure is applied in a preparation stage prior to replenishing the processing liquid. The longer the pre-depressurization time, the more reliably the processing liquid can be replenished at the intended vacuum pressure. The pressure of the processing liquid supply source 50 (Bottle press in FIG. 5) is a pressure applied to the processing liquid in the processing liquid supply source 50 by the inert gas (pressure by the pressurizing mechanism).

[0045] 5, condition 1 is that the height of the processing liquid supply source 50 is 0.00 m, the vacuum pressure of the assist pump 62 is -10 kPa, the preliminary pressure reduction time of the assist pump 62 is 0.1 s, and the pressurization force of the processing liquid supply source 50 is 0 kPa. Condition 2 is that the height of the processing liquid supply source 50 is 0.45 m, the vacuum pressure of the assist pump 62 is -10 kPa, the preliminary pressure reduction time of the assist pump 62 is 0.1 s, and the pressurization force of the processing liquid supply source 50 is 0 kPa. Condition 3 is that the height of the processing liquid supply source 50 is 0.45 m, the vacuum pressure of the assist pump 62 is 1 kPa, the preliminary pressure reduction time of the assist pump 62 is 0.1 s, and the pressurization force of the processing liquid supply source 50 is 5 kPa. Condition 4 is that the height of the processing liquid supply source 50 is 0.45 m, the vacuum pressure of the assist pump 62 is 1 kPa, the preliminary pressure reduction time of the assist pump 62 is 0.1 s, and the pressurizing force of the processing liquid supply source 50 is 50 kPa.

[0046] 6 shows the results of visually checking the foaming state in each region after conducting an experiment under the above conditions 1 to 4. Regions 1 to 8 in FIG. 6 correspond to regions 1 to 8 in FIG. 4. That is, region 1 is the flow path between the processing liquid supply source 50 and the intermediate tank 61, region 2 is inside the intermediate tank 61, region 3 is the flow path between the intermediate tank 61 and the assist pump 62, and region 4 is the flow path between the trap unit 72 and the pump 71. Furthermore, region 5 is inside the pump 71, region 6 is the flow path between the pump 71 and the dispense valve V2, region 7 is inside the dispense valve V2, and region 8 is inside the liquid supply pipe 42 between the dispense valve V2 and the nozzle 41.

[0047] As shown in Fig. 6, under conditions 1 and 2, foaming was observed in regions 1 and 2. Under condition 3, foaming was observed in regions 4 and 8. Under condition 4, foaming was observed in region 8.

[0048] Fig. 7 shows the measurement results of the negative pressure integrated value and the presence or absence of foaming under each condition in regions 1, 4, and 8. The horizontal axis of Fig. 7 shows each condition, and the vertical axis shows the negative pressure integrated value.

[0049] The following can be said from Figures 6 and 7. Foaming occurs at the point first affected by negative pressure The processing liquid that has bubbled once in the region 1 immediately downstream of the processing liquid supply source 50 has a low nitrogen content, so it is difficult to bubble again. The processing liquid that has bubbled in the region 4 in the pump flow path system 70 flows and grows as microbubbles, and tends to bubble in the region 8 immediately before discharge.

[0050] Based on the above results, the inventors have found that "if foaming is performed on the upstream side of the supply system, foaming on the downstream side immediately before discharge can be prevented, preventing foam from being deposited on the workpiece W." Based on this finding, in the treatment liquid supply device according to this embodiment, control is performed to cause foaming on the upstream side by using the influence of negative pressure.

[0051] Specifically, when the state of the processing liquid near the nozzle 41 in the processing liquid flow path satisfies a predetermined bubble generation condition, the control device 100 controls the valve V81 of the pressurizing mechanism and the gas supply source 81 so that the pressurizing force of the inert gas is smaller than the normal value. This control facilitates negative pressure in the processing liquid flow path near the processing liquid supply source 50, making it easier to generate bubbles upstream of the processing liquid flow path. By generating bubbles upstream once, it is possible to suppress the generation of bubbles near the nozzle 41. For example, when the bubble generation condition is satisfied, the control device 100 may control the valve V81 of the pressurizing mechanism and the gas supply source 81 so that the pressurizing force of the inert gas applied to the processing liquid in the processing liquid supply source 50 is between 0 KPa and 5 KPa. The control device 100 may also control the valve V81 of the pressurizing mechanism and the gas supply source 81 so that the pressurizing force during normal operation, when the bubble generation condition is not satisfied, is approximately 20 to 50 KPa.

[0052] The control device 100 may determine that the foam generation condition is satisfied when the foam detection unit detects foam near the nozzle 41. An example of the foam detection unit will now be described with reference to FIG.

[0053] FIG. 8 is a schematic diagram showing an example of a foam detection unit. In FIG. 8, three types of foam detection units 90A, 90B, and 90C are illustrated. The foam detection units 90A, 90B, and 90C are provided near the nozzle 41 and detect bubbles contained in the treatment liquid near the nozzle 41. In this way, the foam detection units 90A, 90B, and 90C detect bubbles contained in the treatment liquid downstream of the pump 71 in the treatment liquid flow path. The foam detection units 90A, 90B, and 90C transmit the detection results to the control device 100.

[0054] The bubble detector 90A shown in FIG. 8(a) is a camera provided for monitoring the nozzle 41. For example, a camera conventionally provided for monitoring the discharge status of the nozzle 41 may be used as the camera (the same camera may be used for both purposes). The bubble detector 90B shown in FIG. 8(b) is a foreign matter detector including an irradiation unit that irradiates light onto the treatment liquid flowing through the liquid feed tube 42 of the treatment liquid flow path and a light receiving unit that receives light transmitted through the treatment liquid flowing through the liquid feed tube 42. The bubble detector 90C shown in FIG. 8(c) is a tube sensor incorporated in the liquid feed tube 42 of the treatment liquid flow path. The bubble detector may be a combination of the above-described bubble detectors 90A, 90B, and 90C, or may have a configuration other than the above-described bubble detectors 90A, 90B, and 90C.

[0055] In a state where at least the bubble generation condition is satisfied, the position of the processing liquid supply source 50 may be located vertically below the position of the intermediate tank 61, as shown in the right diagram of Fig. 9. This makes it easier to create a negative pressure in the processing liquid flow path between the processing liquid supply source 50 and the intermediate tank 61.

[0056] Furthermore, when the bubble generation condition is satisfied, the control device 100 may control the assist pump 62 so as to increase the vacuum pressure. By such control, the upstream side of the assist pump 62 in the treatment liquid flow path is more likely to be under negative pressure, which makes it easier to generate bubbles on the upstream side of the treatment liquid flow path.

[0057] As described above, the assist pump 62 can set three vacuum pressures: a first vacuum pressure, a second vacuum pressure greater than the first vacuum pressure, and a third vacuum pressure greater than the first vacuum pressure but less than the second vacuum pressure. The first vacuum pressure may be, for example, a vacuum pressure used in normal times when the foam generation condition is not met. The second vacuum pressure is, for example, a vacuum pressure set when the foam generation condition is met. The third vacuum pressure is, for example, a vacuum pressure used during preliminary pressure reduction before the second vacuum pressure is set. The first vacuum pressure may be, for example, approximately -50 to -20 Kpa. The second vacuum pressure may be, for example, approximately 10 to 45 Kpa. The third vacuum pressure may be, for example, approximately -20 to 10 Kpa.

[0058] When the foam generation condition is satisfied, the control device 100 controls the assist pump 62 so that the vacuum pressure is set to the second vacuum pressure. In particular, when setting the vacuum pressure to the second vacuum pressure, the control device 100 controls the assist pump 62 so that the vacuum pressure is first set to the third vacuum pressure for a predetermined pre-depressurization time, and then the vacuum pressure is set to the second vacuum pressure.

[0059] FIG. 10 is a diagram illustrating a manner in which the internal pressure (vacuum pressure) of the assist pump 62 is gradually reduced. FIG. 10(a) is a diagram illustrating the monitored negative pressure when the vacuum pressure is immediately set to the second vacuum pressure without gradually reducing it, and FIG. 10(b) is a diagram illustrating the monitored negative pressure when the vacuum pressure is set to the third vacuum pressure during preliminary pressure reduction and then set to the second vacuum pressure. In FIGS. 10(a) and 10(b), the horizontal axis represents time, the vertical axis represents the negative pressure value, the solid line represents the vacuum pressure, and the dashed line represents the monitored negative pressure value. As shown in FIG. 10(b), by gradually increasing the vacuum pressure after preliminary pressure reduction, a sudden change in the monitored negative pressure value is suppressed (a spike in the negative pressure inside the assist pump 62 is suppressed), and a sudden disruption of the pressure in the flow path is suppressed.

[0060] The control device 100 is configured with one or more control computers. For example, the control device 100 has a circuit 120 shown in Fig. 5. The circuit 120 includes one or more processors 121, a memory 122, a storage 123, an input / output port 124, and a timer 125.

[0061] The storage 123 has a computer-readable storage medium such as a hard disk. The storage medium stores a program for causing the coating and developing apparatus 2 to execute the liquid processing procedure described below. The storage medium may be a removable medium such as a non-volatile semiconductor memory, a magnetic disk, or an optical disk. The memory 122 temporarily stores the program loaded from the storage medium of the storage 123 and the results of calculations by the processor 121. The processor 121 executes the program in cooperation with the memory 122 to configure each of the functional modules described above. The input / output port 124 inputs and outputs electrical signals to and from each component of the processing liquid supply unit 30.

[0062] The hardware configuration of the control device 100 is not necessarily limited to configuring each functional module by a program. For example, each functional module of the control device 100 may be configured by a dedicated logic circuit or an ASIC (Application Specific Integrated Circuit) that integrates such dedicated logic circuits.

[0063] Next, the effects of the processing liquid supply device according to this embodiment will be described.

[0064] The processing liquid supply device according to this embodiment includes a processing liquid supply source 50 that stores processing liquid, a pressurizing mechanism that pressurizes the processing liquid in the processing liquid supply source 50 with an inert gas, and a processing liquid flow path that is a flow path for the processing liquid from the processing liquid supply source 50. The processing liquid supply device also includes a nozzle 41 that ejects the processing liquid supplied through the processing liquid flow path onto the workpiece W, and a control device 100 that controls the operation of the pressurizing mechanism. When the state of the processing liquid near the nozzle 41 in the processing liquid flow path satisfies predetermined bubble generation conditions for bubble generation, the control device 100 controls the pressurizing mechanism so that the pressurizing force of the inert gas is smaller than a predetermined normal value.

[0065] The inventors conducted extensive research into the mechanism of foaming and discovered that foaming occurs first at locations affected by negative pressure, and that once foamed, the processing liquid with a reduced nitrogen content is less likely to re-foam. Based on this finding, the processing liquid supply device according to this embodiment controls the pressurizing mechanism so that, when the state of the processing liquid near the nozzle 41 satisfies a predetermined bubble-generation condition, the pressure applied to the processing liquid in the processing liquid supply source 50 by the inert gas is reduced compared to normal. As a result, when the bubble-generation condition is satisfied, the processing liquid flow path near the processing liquid supply source (i.e., the upstream portion of the entire processing liquid flow path) is more likely to be under negative pressure, making it easier for foaming to occur upstream of the processing liquid flow path. This configuration allows the processing liquid that has foamed upstream of the processing liquid flow path and is less likely to re-foam to flow downstream of the processing liquid flow path, thereby appropriately preventing bubbles from being contained in the processing liquid discharged from the nozzle 41 (i.e., bubbles from being deposited on the workpiece W). As described above, the processing liquid supply device according to this embodiment can prevent bubbles from being deposited on the workpiece W, resulting in defects.

[0066] The processing liquid supply device further includes a bubble detection unit that detects bubbles contained in the processing liquid near the nozzle 41. When bubbles are detected by the bubble detection unit, the control device 100 may determine that the bubble generation condition is met and control the pressurization mechanism so that the pressurization force of the inert gas is reduced below a predetermined normal value. In this way, by reducing the pressurization force of the inert gas after bubbles are actually detected, it is possible to adjust the pressurization at an appropriate time.

[0067] The processing liquid supply device further includes a pump 71 provided in the processing liquid flow path and sending the processing liquid toward the nozzle 41, and an assist pump 62 provided upstream of the pump 71 in the processing liquid flow path and sending the processing liquid toward the pump 71. The assist pump 62 may be configured to set a first vacuum pressure and a second vacuum pressure greater than the first vacuum pressure as vacuum pressures used when replenishing the processing liquid sent toward the pump 71. The control device 100 may control the assist pump 62 so that the vacuum pressure is set to the second vacuum pressure when at least a foam generation condition is satisfied. In this way, by increasing the vacuum pressure of the assist pump 62 when the foam generation condition is satisfied, the pressure upstream of the assist pump 62 is more likely to be negative. As a result, the processing liquid that has foamed upstream of the processing liquid flow path and is less likely to re-foam flows downstream of the processing liquid flow path, thereby appropriately preventing bubbles from being included in the processing liquid discharged from the nozzle 41 (from being deposited on the workpiece W).

[0068] The assist pump 62 may be capable of setting a third vacuum pressure that is greater than the first vacuum pressure and less than the second vacuum pressure as the vacuum pressure when replenishing the processing liquid to be sent toward the pump 71. When setting the vacuum pressure to the second vacuum pressure, the control device 100 may control the assist pump 62 so that the vacuum pressure is first set to the third vacuum pressure for a predetermined pre-depressurization time, and then the vacuum pressure is set to the second vacuum pressure. In this way, by increasing the vacuum pressure in stages, it is possible to prevent the positive pressure in the flow path from being suddenly disturbed.

[0069] The bubble detection unit may detect bubbles contained in the processing liquid downstream of the pump 71 in the processing liquid flow path. With this configuration, it is possible to appropriately detect whether bubbles that may become defects (bubbles that may land on the workpiece W) are present.

[0070] The foam detection unit 90A may have a camera provided for monitoring the nozzle 41. According to such a configuration, foam can be detected by utilizing the camera for monitoring the nozzle 41 without adding any additional configuration.

[0071] The bubble detector 90B may have a foreign matter detector including an irradiator that irradiates light onto the treatment liquid flowing through the treatment liquid flow path and a light receiver that receives light that has passed through the treatment liquid flow path. This configuration allows for appropriate bubble detection with a simple configuration.

[0072] The bubble detector 90C may have a tube sensor incorporated in the treatment liquid flow path, which allows bubbles to be detected appropriately with a simple configuration.

[0073] The processing liquid supply device may further include an intermediate tank 61 that is provided upstream of the assist pump 62 in the processing liquid flow path, and that stores the processing liquid supplied from the processing liquid supply source 50 and sends the processing liquid downstream. With this configuration, bubbles generated in the processing liquid flow path near the processing liquid supply source 50 (i.e., the upstream portion of the entire processing liquid flow path) can be appropriately collected in the intermediate tank 61.

[0074] In the above-described processing liquid supply device, when at least the bubble generation condition is satisfied, the processing liquid supply source 50 may be positioned vertically lower than the intermediate tank 61. With such a configuration, a negative pressure is created in the processing liquid flow path between the processing liquid supply source 50 and the intermediate tank 61, making it easier to generate bubbles.

[0075] When the bubble generation conditions are satisfied, the control device 100 may control the pressurizing mechanism so that the pressurizing force of the inert gas is 0 KPa or more and 5 KPa or less, thereby sufficiently reducing the pressurizing force and creating a negative pressure on the upstream side of the treatment liquid flow path, making it easier to generate bubbles.

[0076] The second vacuum pressure may be 10 Kpa or more and 45 Kpa or less, which makes it possible to make the vacuum pressure sufficiently large and create a negative pressure on the upstream side of the treatment liquid flow path, thereby making it easier to generate bubbles.

[0077] Although the present embodiment has been described above, the present disclosure is not limited to the above embodiment.

[0078] For example, in the above embodiment, the pressurization force of the processing liquid in the processing liquid supply source by the inert gas is reduced only when the bubble generation condition is satisfied. However, this is not limiting. For example, the control device (controller) may control the pressurization mechanism so that the processing liquid is pressurized by the inert gas only during the venting process related to the intermediate tank, and is not pressurized by the inert gas during other processes. During the venting process, pressurization of the processing liquid by the inert gas is essential because, without pressurization by the inert gas, the processing liquid may backflow from other lines. On the other hand, it is believed that the processing liquid can be appropriately supplied even if the pressurization by the inert gas is zero during other processes. By configuring the processing liquid not to be pressurized by the inert gas except during the venting process, the processing liquid flow path near the processing liquid supply source (i.e., the upstream portion of the entire processing liquid flow path) is likely to become negative pressure, making it more likely to generate bubbles upstream of the processing liquid flow path. With this configuration, the processing liquid that has foamed upstream of the processing liquid flow path and is now less likely to re-foam flows into the downstream side of the processing liquid flow path, thereby appropriately preventing bubbles from being included in the processing liquid ejected from the nozzle (bubbles from landing on the object to be processed).

[0079] 12, two pump flow path systems 70A and 70B may be provided for one processing liquid supply source, and assist pumps 62A and 62B may be provided corresponding to the pump flow path systems 70A and 70B, respectively. In this case, the flow path branches downstream of the intermediate tank 61 into the assist pump 62A side and the assist pump 62B side. Furthermore, the flow path may branch downstream of each of the pump flow path systems 70A and 70B, and two nozzles may be provided for each. That is, a branch may be provided downstream of the pump flow path system 70A, and a dispense valve V2A and a nozzle 41A may be provided, and a dispense valve V2B and a nozzle 41B may be provided. Furthermore, a branch may be provided downstream of the pump flow path system 70B, and a dispense valve V2C and a nozzle 41C may be provided, and a dispense valve V2D and a nozzle 41D may be provided.

[0080] Finally, various exemplary embodiments included in the present disclosure are described below in [E1] to [E15].

[0081] [E1] a processing liquid supply source that stores a processing liquid; a pressurizing mechanism for pressurizing the processing liquid in the processing liquid supply source with an inert gas; a processing liquid flow path that is a flow path for the processing liquid from the processing liquid supply source; a nozzle that discharges the treatment liquid supplied through the treatment liquid flow path onto the treatment object; a control unit that controls the operation of the pressure mechanism, The control unit A processing liquid supply device that controls the pressurizing mechanism so that the pressurizing force of the inert gas is smaller than a predetermined normal value when the state of the processing liquid near the nozzle in the processing liquid flow path satisfies a predetermined bubble generation condition for bubble generation.

[0082] [E2] a bubble detector that detects bubbles contained in the treatment liquid near the nozzle; The control unit A processing liquid supply device according to [E1], which, when bubbles are detected by the bubble detection unit, determines that the bubble generation condition is met and controls the pressurizing mechanism so that the pressurizing force applied by the inert gas is smaller than a predetermined normal value.

[0083] [E3] a first pump provided in the treatment liquid flow path for sending the treatment liquid toward the nozzle; a second pump that is provided upstream of the first pump in the treatment liquid flow path and that sends the treatment liquid toward the first pump, the second pump is capable of setting a first vacuum pressure and a second vacuum pressure higher than the first vacuum pressure as vacuum pressures used when replenishing the processing liquid sent toward the first pump; The control unit The processing liquid supplying apparatus according to [E2], wherein the second pump is controlled so that the vacuum pressure is set to the second vacuum pressure at least when the bubble generation condition is satisfied.

[0084] [E4] the second pump is capable of setting a third vacuum pressure, which is higher than the first vacuum pressure and lower than the second vacuum pressure, as a vacuum pressure when replenishing the processing liquid sent toward the first pump; The control unit The processing liquid supply device according to [E3], wherein when the vacuum pressure is set to the second vacuum pressure, the second pump is controlled so that the vacuum pressure is first set to the third vacuum pressure for a predetermined pre-depressurization time, and then the vacuum pressure is set to the second vacuum pressure.

[0085] [E5] The treatment liquid supplying device according to [E3] or [E4], wherein the bubble detection unit detects bubbles contained in the treatment liquid downstream of the first pump in the treatment liquid flow path.

[0086] [E6] The processing liquid supplying apparatus according to [E5], wherein the bubble detection unit has a camera provided for monitoring the nozzle.

[0087] [E7] The processing liquid supply device according to [E5] or [E6], wherein the bubble detection unit has a foreign matter detection unit including an irradiation unit that irradiates light onto the processing liquid flowing through the processing liquid flow path, and a light receiving unit that receives light that has passed through the processing liquid flowing through the processing liquid flow path.

[0088] [E8] The treatment liquid supplying device according to any one of [E5] to [E7], wherein the bubble detecting unit has a tube sensor incorporated in the treatment liquid flow path.

[0089] [E9] The processing liquid supply device according to any one of [E3] to [E8], further comprising an intermediate tank provided upstream of the second pump in the processing liquid flow path, for storing the processing liquid supplied from the processing liquid supply source and for sending the processing liquid downstream.

[0090] [E10] The processing liquid supply device according to [E9], wherein, at least in a state where the bubble generation condition is satisfied, the processing liquid supply source is positioned vertically below the intermediate tank.

[0091] [E11] The processing liquid supply device according to any one of [E1] to [E10], wherein the control unit controls the pressurizing mechanism so that the pressurizing force of the inert gas is 0 Kpa or more and 5 Kpa or less when the bubble generation condition is satisfied.

[0092] [E12] The processing liquid supplying device according to any one of [E1] to [E10], wherein the second vacuum pressure is 10 Kpa or more and 45 Kpa or less.

[0093] [E13] an assist pump provided upstream of a pump flow path system that supplies a processing liquid to a nozzle that discharges the processing liquid onto a processing object, a first vacuum pressure and a second vacuum pressure higher than the first vacuum pressure can be set as vacuum pressures when replenishing the treatment liquid to be sent to the pump flow path system; an assist pump, the vacuum pressure of which is set to the second vacuum pressure when the state of the treatment liquid in the vicinity of the nozzle satisfies a predetermined bubble generation condition related to bubble generation;

[0094] [E14] A third vacuum pressure that is greater than the first vacuum pressure and less than the second vacuum pressure can be further set, An assist pump according to [E13], wherein when the vacuum pressure is set to the second vacuum pressure, the vacuum pressure is first set to the third vacuum pressure for a predetermined pre-depressurization time, and then the vacuum pressure is set to the second vacuum pressure.

[0095] [E15] a processing liquid supply source that stores a processing liquid; a pressurizing mechanism for pressurizing the processing liquid in the processing liquid supply source with an inert gas; a processing liquid flow path that is a flow path for the processing liquid from the processing liquid supply source; a nozzle that discharges the treatment liquid supplied through the treatment liquid flow path onto the treatment object; an intermediate tank provided in the treatment liquid flow path, for storing the treatment liquid supplied from the treatment liquid supply source and for sending the treatment liquid downstream; a control unit that controls the operation of the pressure mechanism, The control unit The processing liquid supply device controls the pressurization mechanism so that the processing liquid is pressurized with the inert gas only during vent processing related to the intermediate tank, and is not pressurized with the inert gas during other processing times. [Explanation of symbols]

[0096] U1...liquid processing unit, V81...valve, W...work, 41...nozzle, 50...processing liquid supply source, 61...intermediate tank, 62...assist pump, 71...pump, 81...gas supply source, 90A, 90B, 90C...foam detection section, 100...control device.

Claims

1. a processing liquid supply source that stores a processing liquid; a pressurizing mechanism for pressurizing the processing liquid in the processing liquid supply source with an inert gas; a processing liquid flow path that is a flow path for the processing liquid from the processing liquid supply source; a nozzle that discharges the treatment liquid supplied through the treatment liquid flow path onto the treatment object; a control unit that controls the operation of the pressure mechanism, The control unit A processing liquid supply device that controls the pressurizing mechanism so that the pressurizing force of the inert gas is smaller than a predetermined normal value when the state of the processing liquid near the nozzle in the processing liquid flow path satisfies a predetermined bubble generation condition for bubble generation.

2. a bubble detector that detects bubbles contained in the treatment liquid near the nozzle; The control unit 2. The processing liquid supply device according to claim 1, wherein when bubbles are detected by the bubble detection unit, it is determined that the bubble generation condition is met, and the pressure mechanism is controlled so that the pressure applied by the inert gas is smaller than a predetermined normal value.

3. a first pump provided in the treatment liquid flow path for sending the treatment liquid toward the nozzle; a second pump that is provided upstream of the first pump in the treatment liquid flow path and that sends the treatment liquid toward the first pump, the second pump is capable of setting a first vacuum pressure and a second vacuum pressure higher than the first vacuum pressure as vacuum pressures used when replenishing the processing liquid sent toward the first pump; The control unit 3. The processing liquid supplying apparatus according to claim 2, wherein the second pump is controlled so that the vacuum pressure is set to the second vacuum pressure at least when the bubble generation condition is satisfied.

4. the second pump is capable of setting a third vacuum pressure, which is higher than the first vacuum pressure and lower than the second vacuum pressure, as a vacuum pressure when replenishing the processing liquid sent toward the first pump; The control unit 4. The processing liquid supply device according to claim 3, wherein when the vacuum pressure is set to the second vacuum pressure, the second pump is controlled so that the vacuum pressure is first set to the third vacuum pressure for a predetermined pre-depressurization time, and then the vacuum pressure is set to the second vacuum pressure.

5. The treatment liquid supply device according to claim 3 , wherein the bubble detector detects bubbles contained in the treatment liquid downstream of the first pump in the treatment liquid flow path.

6. 6. The processing liquid supply apparatus according to claim 5, wherein the bubble detection unit has a camera provided for monitoring the nozzle.

7. The processing liquid supply device according to claim 5, wherein the bubble detection unit has a foreign matter detection unit including an irradiation unit that irradiates light onto the processing liquid flowing through the processing liquid flow path, and a light receiving unit that receives light that has passed through the processing liquid flowing through the processing liquid flow path.

8. 6. The processing liquid supply apparatus according to claim 5, wherein the bubble detection unit has a tube sensor incorporated in the processing liquid flow path.

9. 4. The processing liquid supply device according to claim 3, further comprising an intermediate tank provided upstream of the second pump in the processing liquid flow path, for storing the processing liquid supplied from the processing liquid supply source and for sending the processing liquid downstream.

10. 10. The processing liquid supply device according to claim 9, wherein the processing liquid supply source is located vertically below the intermediate tank when at least the bubble generation condition is satisfied.

11. A processing liquid supply device according to any one of claims 1 to 10, wherein the control unit controls the pressure mechanism so that the pressure applied by the inert gas is greater than or equal to 0 KPa and less than or equal to 5 KPa when the bubble generation condition is met.

12. 11. The processing liquid supplying apparatus according to claim 3, wherein the second vacuum pressure is equal to or greater than 10 Kpa and equal to or less than 45 Kpa.

13. an assist pump provided upstream of a pump flow path system that supplies a processing liquid to a nozzle that discharges the processing liquid onto a processing object, a first vacuum pressure and a second vacuum pressure higher than the first vacuum pressure can be set as vacuum pressures when replenishing the processing liquid to be sent to the pump flow path system; an assist pump, the vacuum pressure of which is set to the second vacuum pressure when the state of the treatment liquid in the vicinity of the nozzle satisfies a predetermined bubble generation condition related to bubble generation;

14. A third vacuum pressure that is greater than the first vacuum pressure and less than the second vacuum pressure can be further set, 14. The assist pump according to claim 13, wherein, when the vacuum pressure is set to the second vacuum pressure, the vacuum pressure is first set to the third vacuum pressure for a predetermined pre-depressurization time, and then the vacuum pressure is set to the second vacuum pressure.

15. a processing liquid supply source that stores a processing liquid; a pressurizing mechanism for pressurizing the processing liquid in the processing liquid supply source with an inert gas; a processing liquid flow path that is a flow path for the processing liquid from the processing liquid supply source; a nozzle that discharges the treatment liquid supplied through the treatment liquid flow path onto the treatment object; an intermediate tank provided in the treatment liquid flow path, for storing the treatment liquid supplied from the treatment liquid supply source and for sending the treatment liquid downstream; a control unit that controls the operation of the pressure mechanism, The control unit The processing liquid supply device controls the pressurization mechanism so that the processing liquid is pressurized with the inert gas only during vent processing related to the intermediate tank, and is not pressurized with the inert gas during other processing times.

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