Substrate processing apparatus and substrate processing method

Abstract

This invention provides a substrate processing apparatus that can suppress problems caused by the mixing of the processing solution used to process the substrate and the processing solution used to clean the filter. [Solution] The substrate processing apparatus (100) includes a circulation pipe (21) that includes a portion that branches into two pipes, a first branch pipe and a second branch pipe; a filter (53) that filters the first processing liquid and is provided at least in the first branch pipe; and a controller (73) that performs a first cleaning process by flowing the second processing liquid in the reverse direction into the first branch pipe, and then flowing the third processing liquid in the reverse direction into the first branch pipe, and after the first cleaning process, flows the first processing liquid in the forward direction into the first branch pipe.

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method.

Background Art

[0002] [[ID=ll]] An example of a substrate processing apparatus for peeling a film adhered to a substrate with a peeling solution is disclosed in Patent Document 1. When the peeling process is completed, the substrate processing apparatus performs a filter cleaning process for cleaning the circulation filter by causing the cleaning solution to flow backward through the circulation filter. Thereby, since the fragments of the photoresist film attached to the circulation filter can be removed, the maintenance of the circulation filter can be easily performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the substrate processing apparatus of Patent Document 1, when the peeling process is restarted with the cleaning solution filled in the vicinity of the circulation filter after the filter cleaning process, the peeling solution and the cleaning solution are mixed. At this time, depending on the types or states of the peeling solution and the cleaning solution, problems may occur.

[0005] One aspect of the present invention aims to realize a substrate processing apparatus or the like that can suppress problems caused by mixing a processing solution for processing a substrate and a processing solution for cleaning a filter.

Means for Solving the Problems

[0006] To solve the above problems, a substrate processing apparatus according to one aspect of the present invention includes: a substrate processing tank for processing a substrate with a liquid containing a first processing liquid; a circulation pipe connected to the substrate processing tank at both ends and including a portion that branches into two pipes, a first branch pipe and a second branch pipe; a filter for filtering the first processing liquid; a second processing liquid supply unit for supplying a second processing liquid having different components from the first processing liquid; a third processing liquid supply unit for supplying a third processing liquid having different components from the second processing liquid; a discharge unit for discharging a liquid containing at least the first processing liquid or the second processing liquid; a controller; a first switching unit for switching whether to flow the first processing liquid through the first branch pipe or the second branch pipe; and a switch for switching whether to flow the second processing liquid through the first branch pipe or the second branch pipe, and whether to flow the third processing liquid through the first branch pipe or the second branch pipe. The device comprises a second switching unit, the filter is provided in at least the first branch pipe, and the controller performs a first cleaning process by (1) controlling the first switching unit to cause the first processing liquid to flow in the second branch pipe in the forward direction, during the period in which the first processing liquid flows in the second branch pipe, by controlling the second switching unit to cause the second processing liquid to flow in the first branch pipe in the reverse direction, causing the liquid containing at least the first processing liquid to be discharged from the discharge unit, and then further controlling the second switching unit to cause the third processing liquid to flow in the first branch pipe in the reverse direction, causing the liquid containing at least the second processing liquid to be discharged from the discharge unit, and (2) after the first cleaning process, causing the first processing liquid to flow in the first branch pipe in the forward direction and the second and third processing liquids to flow in the second branch pipe in the reverse direction, or stopping the supply of the second and third processing liquids.

[0007] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the circulation piping has a first branch point and a second branch point that branch into the first branch piping and the second branch piping, the first switching unit includes a pair of first circulation valves provided in the first branch piping and a pair of second circulation valves provided in the second branch piping, the filter is provided between the pair of first circulation valves, and the controller may open the pair of first circulation valves and close the pair of second circulation valves to allow the first processing liquid to flow into the first branch piping, and close the pair of first circulation valves and open the pair of second circulation valves to allow the first processing liquid to flow into the second branch piping.

[0008] Furthermore, a substrate processing apparatus according to one aspect of the present invention further comprises: a first supply pipe connecting the second processing liquid supply unit and the third processing liquid supply unit to the first branch pipe; a second supply pipe connecting the second processing liquid supply unit and the third processing liquid supply unit to the second branch pipe; and a discharge pipe connecting the first branch pipe and the second branch pipe to the discharge unit, wherein the first branch pipe has a third branch point on the downstream side in the forward direction, between the filter and the first circulation valve, which branches off from the first supply pipe; the second branch pipe has a fourth branch point on the downstream side in the forward direction, between the filter and the second circulation valve, which branches off from the second supply pipe; the first branch pipe has a fifth branch point on the upstream side in the forward direction, between the filter and the first circulation valve, which branches off from the discharge pipe; and the second branch pipe has a sixth branch point on the upstream side in the forward direction, between the filter and the second circulation valve, which branches off from the discharge pipe. The second switching unit has a branching point and comprises a first supply valve located on the first supply piping side of the third branching point, a second supply valve located on the second supply piping side of the fourth branching point, a first discharge valve located on the discharge piping side of the fifth branching point, and a second discharge valve located on the discharge piping side of the sixth branching point. The controller may, while the first processing liquid is flowing through the first branching pipe, open the first supply valve, open the second supply valve, close the first discharge valve, and open the second discharge valve, while the first processing liquid is flowing through the second branching pipe, open the first supply valve, close the second supply valve, open the first discharge valve, and close the second discharge valve.

[0009] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the filter is further provided in the second branch pipe, and the controller may (1) control the first switching unit to cause the first processing liquid to flow in the forward direction through the first branch pipe, and then control the second switching unit to cause the second processing liquid to flow in the reverse direction through the second branch pipe, thereby causing the liquid containing at least the first processing liquid to be discharged from the discharge unit, and thereafter, further control the second switching unit to cause the third processing liquid to flow in the reverse direction through the first branch pipe, thereby causing the liquid containing at least the second processing liquid to be discharged from the discharge unit, and (2) after the second cleaning process, the first processing liquid may flow in the forward direction through the second branch pipe, and the second and third processing liquids may flow in the reverse direction through the first branch pipe, or the supply of the second and third processing liquids may be stopped.

[0010] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the first processing solution may be a processing solution containing sulfuric acid, and the second processing solution may be pure water.

[0011] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the first processing solution may be phosphoric acid, and the second processing solution may be a processing solution containing hydrofluoric acid.

[0012] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the circulation piping may be equipped with a heater for heating the first processing liquid to a predetermined temperature, and the second processing liquid supply unit may supply the second processing liquid at room temperature.

[0013] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the third processing liquid supply unit supplies the third processing liquid to the filter by branching off from the circulation piping, and the third processing liquid may be the first processing liquid circulating in the circulation piping.

[0014] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the substrate processing tank comprises an inner tank for storing the first processing liquid supplied from the circulation piping, and an outer tank for storing the first processing liquid that overflows from the inner tank, with one end of the circulation piping connected to the outer tank and the other end connected to the inner tank, and the third processing liquid supply unit may supply the third processing liquid to the filter at a flow rate less than the flow rate of the first processing liquid that overflows from the inner tank to the outer tank.

[0015] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the controller may, in the second cleaning process, control the first switching unit to cause the third processing liquid to flow in the second branch pipe in the reverse direction immediately before the end of the period during which the first processing liquid is circulated in the first branch pipe, and in the first cleaning process, control the first switching unit to cause the third processing liquid to flow in the first branch pipe in the reverse direction immediately before the end of the period during which the first processing liquid is circulated in the second branch pipe.

[0016] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the second switching unit further comprises a first-to-second supply valve for switching whether or not the second processing liquid flows from the second processing liquid supply unit to the first branch pipe, a first-to-third supply valve for switching whether or not the third processing liquid flows from the third processing liquid supply unit to the first branch pipe, a second-to-second supply valve for switching whether or not the second processing liquid flows from the second processing liquid supply unit to the second branch pipe, and a second-to-third supply valve for switching whether or not the third processing liquid flows from the third processing liquid supply unit to the second branch pipe, and the controller may perform control to open the first circulation valve, close the second circulation valve, and with the second supply valve open, open the second-to-second supply valve for a predetermined period, then open the second-to-third supply valve for a predetermined period, and with the second circulation valve open, close the first circulation valve, and with the first supply valve open, open the first-to-second supply valve for a predetermined period, then open the first-to-third supply valve for a predetermined period.

[0017] Furthermore, a substrate processing apparatus according to one aspect of the present invention further comprises a main filter provided downstream of the filter in the circulation piping, wherein the filter is a pre-filter, and the pore diameter of the main filter may be smaller than the pore diameter of the pre-filter.

[0018] Furthermore, in a substrate processing apparatus according to one aspect of the present invention, the member through which the first processing liquid passes, provided in the substrate processing tank, may be made of a material containing quartz.

[0019] Furthermore, a substrate processing method according to one aspect of the present invention comprises: a substrate processing tank for processing a substrate with a liquid containing a first processing liquid; a circulation pipe connected to the substrate processing tank at both ends and including a portion that branches into two pipes, a first branch pipe and a second branch pipe; a filter for filtering the first processing liquid; a second processing liquid supply unit for supplying a second processing liquid having different components from the first processing liquid; a third processing liquid supply unit for supplying a third processing liquid having different components from the second processing liquid; a discharge unit for discharging a liquid containing at least the first processing liquid or the second processing liquid; a first switching unit for switching whether to flow the first processing liquid into the first branch pipe or the second branch pipe; and a second switching unit for switching whether to flow the second processing liquid into the first branch pipe or the second branch pipe, and whether to flow the third processing liquid into the first branch pipe or the second branch pipe; and a substrate processing method comprising: A substrate processing method in a processing apparatus, wherein the filter is provided in at least the first branch pipe, and (1) during the period in which the first processing liquid is flowed in the forward direction through the second branch pipe by controlling the first switching unit, the second processing liquid is flowed in the reverse direction through the first branch pipe by controlling the second switching unit, causing the liquid containing at least the first processing liquid to be discharged from the discharge unit, and thereafter, by further controlling the second switching unit, the third processing liquid is flowed in the reverse direction through the first branch pipe, causing the liquid containing at least the second processing liquid to be discharged from the discharge unit, thereby performing a first cleaning process, and (2) after the first cleaning process, the first processing liquid is flowed in the forward direction through the first branch pipe and the second and third processing liquids are flowed in the reverse direction through the second branch pipe, or the supply of the second and third processing liquids is stopped.

[0020] Further, a substrate processing method according to an aspect of the present invention includes a substrate processing step of processing a substrate with a liquid containing a first processing liquid in a substrate processing tank, and at least a filter provided in the first branch pipe of a circulation pipe including a portion branched into two pipes, a first branch pipe and a second branch pipe, both ends of which are connected to the substrate processing tank, filtering the first processing liquid flowing in the forward direction in the circulation pipe; and during a period in which the first processing liquid is caused to flow in the forward direction through the second branch pipe by controlling a first switching unit that switches whether to flow the first processing liquid through the first branch pipe or the second branch pipe, controlling a second switching unit that switches whether to flow a second processing liquid having a component different from that of the first processing liquid through the first branch pipe or the second branch pipe, and whether to flow a third processing liquid having a component different from that of the second processing liquid through the first branch pipe or the second branch pipe, causing the second processing liquid to flow in the reverse direction through the first branch pipe, discharging the liquid containing at least the first processing liquid from a discharge unit that discharges the liquid containing at least the first processing liquid or the second processing liquid, and then, by further controlling the second switching unit, causing the third processing liquid to flow in the reverse direction through the first branch pipe, and performing a first cleaning process of discharging the liquid containing at least the second processing liquid from the discharge unit, and a process restart step of restarting circulating the first processing liquid through the first branch pipe after the first cleaning process.

Advantages of the Invention

[0021] According to a substrate processing apparatus and the like according to an aspect of the present invention, it is possible to suppress problems caused by mixing of a processing liquid for processing a substrate and a processing liquid for cleaning a filter.

Brief Description of the Drawings

[0022] <  <  [Figure 1] It is an overall view illustrating a schematic configuration of a substrate processing apparatus according to Embodiment 1. [Figure 2] It is a cross-sectional view illustrating the shape of an upflow pipe. [Figure 3]It is a flowchart exemplifying the operation of the substrate processing apparatus according to Embodiment 1. [Figure 4] It is a timing chart showing the open / closed states of each valve and the control valve included in the switching unit in the substrate processing apparatus according to Embodiment 1. [Figure 5] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 1. [Figure 6] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 1. [Figure 7] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 1. [Figure 8] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 1. [Figure 9] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 1. [Figure 10] It is an overall view exemplifying the schematic configuration of the substrate processing apparatus according to Embodiment 2. [Figure 11] It is a flowchart exemplifying the operation of the substrate processing apparatus according to Embodiment 2. [Figure 12] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 2. [Figure 13] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 2. [Figure 14] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 2. [Figure 15] It is a diagram exemplifying the open / closed states of each valve included in the switching unit in the substrate processing apparatus according to Embodiment 2. [Figure 16] It is an overall view exemplifying the schematic configuration of the substrate processing apparatus according to Embodiment 3. [Figure 17] It is an overall view exemplifying the schematic configuration of the substrate processing apparatus according to Embodiment 4. [Figure 18] This is an overall diagram illustrating the schematic configuration of the substrate processing apparatus according to Embodiment 5. [Modes for carrying out the invention]

[0023] [Embodiment 1] An embodiment of the present invention will be described below with reference to the drawings. In the following description, "A to B" indicating a numerical range means "greater than or equal to A and less than or equal to B" unless otherwise specified.

[0024] (composition) Figure 1 is an overall diagram illustrating the schematic configuration of a substrate processing apparatus 100 according to Embodiment 1. The substrate processing apparatus 100 is a processing apparatus for processing substrates W. The substrate W is, for example, a semiconductor wafer. The substrate processing apparatus 100 in Figure 1 is a so-called batch-type processing apparatus capable of processing a lot of multiple substrates W at once.

[0025] As shown in Figure 1, the substrate processing apparatus 100 comprises a substrate processing tank (substrate processing unit) 1, circulation piping 21, a filter 53, a second processing liquid supply unit 47, a third processing liquid supply unit 48, a discharge unit 45, and a controller (control unit) 73.

[0026] The substrate processing tank 1 processes the substrate W with a first processing solution. The first processing solution is a cleaning solution for cleaning the surface of the substrate W. For example, the first processing solution is a processing solution containing sulfuric acid or phosphoric acid. If the first processing solution contains sulfuric acid, it may be a mixture of sulfuric acid and hydrogen peroxide (SPM: sulfuric acid-hydrogen peroxide mixture). In this case, the substrate processing tank 1 performs so-called SPM cleaning. Through this SPM cleaning, the substrate processing tank 1 removes organic substances such as photoresist that have adhered to the surface of the substrate W. If the first processing solution is phosphoric acid, the substrate processing tank 1 removes the nitride film formed on the surface of the substrate W.

[0027] The substrate processing tank 1 comprises an inner tank 3 and an outer tank 5. The inner tank 3 is a tank for storing the first processing liquid and processing the substrate W. The outer tank 5 is a tank for storing the first processing liquid that overflows from the inner tank 3. Each of the inner tank 3 and the outer tank 5 may be provided with a liquid level sensor 18 for detecting the liquid level of the first processing liquid. The liquid level refers to the height of the liquid level of the first processing liquid stored in the inner tank 3 or the outer tank 5. Furthermore, the inner tank 3 is provided with a temperature sensor (not shown) for detecting the temperature of the first processing liquid.

[0028] The substrate processing apparatus 100 further includes a lifter 11. The lifter 11 is positioned near the substrate processing tank 1. The lifter 11 is configured to move up and down between a "standby position" above the substrate processing tank 1 and a "processing position" inside the inner tank 3. The lifter 11 holds the multiple substrates W in an upright position while maintaining them at predetermined intervals.

[0029] Furthermore, the substrate processing apparatus 100 further includes a first processing liquid supply unit 13. The first processing liquid supply unit 13 supplies the first processing liquid to the inner tank 3. The first processing liquid supply unit 13 is located near the substrate processing tank 1. In addition, the substrate processing apparatus 100 includes a first processing liquid supply pipe 15, one end of which is connected to the first processing liquid supply unit 13 and the other end of which is connected to the inner tank 3, and a control valve 17 for switching between a state in which the first processing liquid can flow through the first processing liquid supply pipe 15 and a state in which it cannot flow.

[0030] The circulation pipe 21 is a pipe connected at both ends to the substrate processing tank 1. The first processing liquid circulates in the forward direction inside the circulation pipe 21. Specifically, one end of the circulation pipe 21 is connected to the outer tank 5. The other end of the circulation pipe 21 is connected to the inner tank 3. The forward direction is the direction in which the first processing liquid flows from the outer tank 5 to the inner tank 3 in the circulation pipe 21. That is, the first processing liquid is circulated from the outer tank 5 through the circulation pipe 21 and supplied from the circulation pipe 21 to the inner tank 3. In other words, the inner tank 3 is a tank that stores the first processing liquid supplied from the circulation pipe 21. The outer tank 5 is a tank that stores the first processing liquid that overflows from the inner tank 3. In the following explanation, "upstream side" and "downstream side" refer to the upstream side and downstream side in the forward direction, respectively.

[0031] The circulation piping 21 is equipped with, in order from upstream, a control valve 23, a filter 53, a bellows pump 27, a control valve 29, a heater 31, and a main filter 33. The control valve 23 switches the circulation piping 21 between a state where the processing liquid can flow and a state where it cannot. The filter 53 and the main filter 33 filter the first processing liquid. As a result, foreign matter in the first processing liquid is collected by the filter 53 and the main filter 33. Details of the filter 53 and the main filter 33 will be described later. The bellows pump 27 pumps the processing liquid forward from the outer tank 5 to the inner tank 3 via the circulation piping 21. The control valve 29 switches the circulation piping 21 between a state where the processing liquid can circulate and a state where it cannot. The heater 31 heats the first processing liquid to a predetermined temperature. The bellows pump 27 also has a built-in stroke sensor 75, and its output is supplied to the controller 73. The stroke sensor 75 detects the end position of the bellows (not shown) in the bellows pump 27 during its reciprocating movement.

[0032] A drain pipe 35 is connected to the downstream side of the bellows pump 27 and the upstream side of the control valve 29. The drain pipe 35 is equipped with a control valve 37 that switches between a state in which the treated liquid flowing through the circulation pipe 21 is discharged from the drain pipe 35 and a state in which it is not. The control valve 37 is opened as needed to discharge the first treated liquid from the drain pipe 35.

[0033] The substrate processing tank 1 further includes an upflow pipe 19 through which the first processing liquid passes. The upflow pipe 19 is a pipe for supplying the first processing liquid, which has circulated through the circulation piping 21, into the interior of the inner tank 3. Part of the upflow pipe 19 is located near the bottom of the inner tank 3. Another part of the upflow pipe 19 penetrates the walls of the inner tank 3 and the outer tank 5 and is exposed to the outside of the substrate processing tank 1.

[0034] The downstream end of the circulation pipe 21 is connected to the portion of the upflow pipe 19 that is exposed to the outside of the substrate processing tank 1. In other words, the circulation pipe 21 is connected to the inner tank 3 via the upflow pipe 19. The upflow pipe 19 may be made of a material containing, for example, quartz.

[0035] Figure 2 is a cross-sectional view illustrating the shape of the upflow pipe 19. For clarity, the aspect ratio of the upflow pipe 19 in Figure 2 differs from that of the actual pipe and Figure 1. As shown in Figure 2, the upflow pipe 19 has a base end portion 19a and an outlet pipe portion 19b.

[0036] The upflow pipe 19 has a plurality of ejection holes 19c from which the first processing liquid is ejected. For simplicity, in Figure 2, only some of the ejection holes 19c are labeled. The ejection holes 19c are provided in the ejection pipe section 19b, but not in the base end section 19a. The entire ejection pipe section 19b and a portion of the base end section 19a are located inside the inner tank 3. Another portion of the base end section 19a penetrates the walls of the inner tank 3 and the outer tank 5 and is exposed to the outside of the substrate processing tank 1. The downstream end of the circulation pipe 21 is connected to the base end section 19a. The first processing liquid flows through the circulation pipe 21 into the base end section 19a and into the inner tank 3 through the ejection holes 19c provided in the ejection pipe section 19b.

[0037] The circulating pipe 21 includes a section that branches into two pipes: a first branch pipe 38 and a second branch pipe 41. The circulating pipe 21 has a first branch point 21a and a second branch point 21b that branch into the first branch pipe 38 and the second branch pipe 41.

[0038] In Embodiment 1, the filter 53 includes a first filter 55 provided in the first branch pipe 38 and a second filter 57 provided in the second branch pipe 41. In the following description, when it is not necessary to distinguish between the first filter 55 and the second filter 57, they may be collectively referred to as "filter 53".

[0039] The main filter 33 is located downstream of the filter 53 in the circulation piping 21. That is, the filter 53 functions as a pre-filter that filters the first treated liquid before it is filtered by the main filter 33. In this case, the pore diameter of the main filter 33 is smaller than the pore diameter of the filter 53. The pore diameter is the average diameter of the holes provided in the filter.

[0040] The pore diameter of filter 53 is, for example, 0.1 mm. The pore diameter of main filter 33 is, for example, 30 nm to 50 nm.

[0041] With the above configuration, the filter 53, which functions as a pre-filter, captures relatively large foreign objects before the main filter 33. This prevents clogging of the main filter 33 by relatively large foreign objects.

[0042] Furthermore, the circulation piping 21 is further equipped with a first switching section 25 and a second switching section 26. The first switching section 25 switches whether the first treatment liquid flows into the first branch pipe 38 or the second branch pipe 41. The second switching section 26 switches whether the second treatment liquid flows into the first branch pipe 38 or the second branch pipe 41, and whether the third treatment liquid flows into the first branch pipe 38 or the second branch pipe 41. The specific configurations of the first switching section 25 and the second switching section 26 will be described later.

[0043] The second processing liquid supply unit 47 supplies a second processing liquid having different components from the first processing liquid. The third processing liquid supply unit 48 supplies a third processing liquid having different components from the second processing liquid. The substrate processing apparatus 100 includes a first supply pipe 62 connecting the second processing liquid supply unit 47 and the third processing liquid supply unit 48 to the first branch pipe 38, and a second supply pipe 80 connecting the second processing liquid supply unit 47 and the third processing liquid supply unit 48 to the second branch pipe 41.

[0044] If the first treatment solution contains sulfuric acid, the second treatment solution may be pure water. This allows organic matter adhering to the substrate W to be removed by the sulfuric acid-containing treatment solution, and also allows the filter 53 that has collected the organic matter (foreign matter) to be properly cleaned with pure water.

[0045] If the first treatment solution is phosphoric acid, the second treatment solution may be a treatment solution containing hydrofluoric acid. This allows the nitride film formed on the substrate W to be removed by phosphoric acid, and the filter 53 that collects silicon (foreign matter) deposited by the phosphoric acid treatment to be properly cleaned by hydrofluoric acid.

[0046] Furthermore, if the first processing solution is phosphoric acid and the second processing solution is a processing solution containing hydrofluoric acid, the second processing solution supply unit 47 may supply pure water to the filter 53 after supplying the second processing solution. Alternatively, the substrate processing apparatus 100 may further include a pure water supply source for supplying pure water to the filter 53, separate from the second processing solution supply unit 47.

[0047] The third treatment solution is a liquid that does not cause bumping when mixed with the first treatment solution. If the first treatment solution contains sulfuric acid, the third treatment solution may be, for example, sulfuric acid. Also, if the first treatment solution is phosphoric acid, the third treatment solution may be, for example, phosphoric acid.

[0048] An example of the specific configuration of the first switching unit 25 is described below. In the example shown in Figure 1, the first switching unit 25 includes a pair of first circulation valves 49, 51 provided in the first branch pipe 38 and a pair of second circulation valves 67, 71 provided in the second branch pipe 41.

[0049] The first circulation valves 49 and 51 switch between a state in which the first processed liquid flows through the first branch pipe 38 and a state in which it does not flow. The first filter 55 is installed between the pair of first circulation valves 49 and 51. Specifically, the first circulation valve 49 is located upstream of the first filter 55 in the forward direction, and the first circulation valve 51 is located downstream.

[0050] The second circulation valves 67 and 71 switch between a state in which the first treated liquid flows through the second branch pipe 41 and a state in which it does not flow. The second filter 57 is installed between the pair of second circulation valves 67 and 71. Specifically, the second circulation valve 67 is located upstream of the second filter 57 in the forward direction, and the second circulation valve 71 is located downstream of the second filter 57.

[0051] The first branch pipe 38 has a third branch point 38a on the downstream side in the forward direction, between the filter 53 and the first circulation valve 51, where it branches off to the first supply pipe 62. The second branch pipe 41 has a fourth branch point 41a on the downstream side in the forward direction, between the filter 53 and the second circulation valve 71, where it branches off to the second supply pipe 80.

[0052] The discharge section 45 discharges a liquid containing at least the first or second processing liquid from the upstream side of the filter 53. The substrate processing apparatus 100 further includes a discharge pipe 60 connecting the first branch pipe 38 and the second branch pipe 41 to the discharge section 45. The first branch pipe 38 has a fifth branch point 38b on the upstream side in the forward direction, between the filter 53 and the first circulation valve 49, where it branches off to the discharge pipe 60. The second branch pipe 41 has a sixth branch point 41b on the upstream side in the forward direction, between the filter 53 and the second circulation valve 67, where it branches off to the discharge pipe 60.

[0053] An example of the specific configuration of the second switching unit 26 is described below. In the example shown in Figure 1, the second switching unit 26 includes a first supply valve 83 located on the first supply pipe 62 side of the third branch point 38a, a second supply valve 87 located on the second supply pipe 80 side of the fourth branch point 41a, a first discharge valve 61 located on the discharge pipe 60 side of the fifth branch point 38b, and a second discharge valve 65 located on the discharge pipe 60 side of the sixth branch point 41b. The first supply valve 83 switches the flow of the second and third processing liquids through the first supply pipe 62 between a state where they flow and a state where they do not. The second supply valve 87 switches the flow of the second and third processing liquids through the second supply pipe 80 between a state where they flow and a state where they do not. The first discharge valve 61 switches the flow of the second and third processing liquids from the first branch pipe 38 to the discharge unit 45 between a state where they flow and a state where they do not. The second discharge valve 65 switches between a state in which the second and third treatment liquids flow from the second branch pipe 41 to the discharge section 45, and a state in which they do not flow.

[0054] The second switching unit 26 further comprises a first-to-second supply valve 63, a first-to-third supply valve 81, a second-to-second supply valve 69, and a second-to-third supply valve 85. The first-to-second supply valve 63 switches whether or not the second processing liquid flows from the second processing liquid supply unit 47 to the first branch pipe 38. The first-to-third supply valve 81 switches whether or not the third processing liquid flows from the third processing liquid supply unit 48 to the first branch pipe 38. The second-to-second supply valve 69 switches whether or not the second processing liquid flows from the second processing liquid supply unit 47 to the second branch pipe 41. The second-to-third supply valve 85 switches whether or not the third processing liquid flows from the third processing liquid supply unit 48 to the second branch pipe 41.

[0055] The controller 73 controls each part of the substrate processing apparatus 100 and controls the operation of the substrate processing apparatus 100. The controller 73 comprises one or more processors or circuits. The processor or circuit may include, but is not limited to, a central processing unit (CPU), a microprocessing unit (MPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), or a field-programmable gateway (FPGA). In Figure 1, the controller 73 includes a CPU 731. The controller 73 also further comprises a memory 732, which is a storage medium. The storage medium may also be called a non-temporary computer-readable medium. The storage medium may include, but is not limited to, a hard disk (HD) or random access memory (RAM). In Figure 1, the dashed arrows indicate the signal flow between each part of the substrate processing apparatus 100 and the controller 73. In this embodiment, the operation that the controller 73 controls and causes each component to perform may be described as if the component is the main operator. Details of what the controller 73 controls will be explained later in the operation of the substrate processing apparatus 100.

[0056] (operation) The operation of the substrate processing apparatus 100 will be explained with reference to Figures 3 to 9. Figure 3 is a flowchart illustrating the operation of the substrate processing apparatus 100. Figure 4 is a timing chart showing the open / closed states of the valves, control valve 17, control valve 23, and control valve 29, provided by the first switching unit 25 and the second switching unit 26. In Figure 4, the open state is indicated as "ON" and the closed state as "OFF". Figures 5 to 9 illustrate the open / closed states of the valves provided by the first switching unit 25 and the second switching unit 26. In Figures 5 to 9, the valves in the closed state of the first switching unit 25 and the second switching unit 26 are shown in black. Also, the controller 73 is omitted in Figures 5 to 9.

[0057] The controller 73 performs the filter selection process (S1) shown in Figure 3. In the filter selection process (S1), the controller 73 selects from the first filter 55 and the second filter 57 of the filter 53 a processing filter that collects foreign matter by circulating the first processing liquid in the forward direction, and a standby filter in which the first processing liquid is not circulated in the forward direction and remains on standby. The controller 73 temporarily stores the filter selection information, which is information about the selected filters 53 for the processing filter and the standby filter, in the controller 73's memory 732 shown in Figure 1. At this time, the controller 73 also controls the first switching unit 25 to switch the piping for circulating the first processing liquid to the one equipped with the filter 53 selected as the processing filter, from among the first branch pipe 38 and the second branch pipe 41.

[0058] The following explanation will use the case where the controller 73 selects the first filter 55 as the processing filter and the second filter 57 as the standby filter during the filter selection process (S1) as an example. When the first filter 55 is the processing filter, the controller 73 temporarily stores the first filter 55 as the processing filter in the controller 73's memory 732 as filter selection information. The controller 73 also controls the first switching unit 25 to open the first circulation valves 49 and 51 and close the second circulation valves 67 and 71.

[0059] In the substrate processing apparatus 100, the first filter 55 and the second filter 57 are sealed with either the first or third processing solution before the filter selection process (S1). In the substrate processing apparatus 100, the controller 73 performs a start-up operation for the filter 53 when the filter 53 is replaced. In the start-up operation, the controller 73 sequentially supplies the first processing solution, the second processing solution, and the third processing solution to the filter 53 to remove foreign matter from the filter 53. Finally, the controller 73 ensures that the filter 53 is sealed with either the first or third processing solution. More specifically, the first filter 55 is sealed with either the first or third processing solution when the substrate processing apparatus 100 begins processing the substrate W. Note that in the filter selection process (S1) in Figure 3, the case where the third processing solution is sealed in the filter 53 is shown for simplification.

[0060] The controller 73 performs the first processing liquid storage process (S2) after the filter selection process (S1). In the first processing liquid storage process (S2), the controller 73 controls the control valve 17 to supply the first processing liquid from the first processing liquid supply unit 13 to the inner tank 3 of the substrate processing tank 1. At this time, the controller 73 confirms that the inner tank 3 has been filled with the first processing liquid at a predetermined liquid level and temperature, based on signals from the liquid level sensor 18 and the temperature sensor. A portion of the first processing liquid supplied to the inner tank 3 overflows and is stored in the outer tank 5.

[0061] After the first processing liquid storage process (S2), the controller 73 performs the circulation processing process (S3) shown in Figure 3. In the circulation processing process (S3), the controller 73 controls the first switching unit 25, the second switching unit 26, the bellows pump 27, the control valve 23, and the control valve 29. Based on information from the memory 732 temporarily stored in the filter selection process (S1), the controller 73 controls the first circulation valves 49 and 51 of the first switching unit 25 in order to circulate the first processing liquid to the first filter 55, which is the processing filter. Specifically, as shown in Figures 4 and 5, the controller 73 opens the pair of first circulation valves 49 and 51 and closes the pair of second circulation valves 67 and 71, thereby allowing the first processing liquid to flow into the first branch pipe 38. The controller 73 also opens the control valves 23 and 29.

[0062] From this point onward, until the processing of the substrate processing apparatus 100 is completed, the controller 73 controls the bellows pump 27 as soon as the first processing liquid reaches the bellows pump 27, causing it to pump the first processing liquid in the forward direction. The controller 73 also keeps the control valves 23 and 29 open. As a result, the controller 73 circulates the first processing liquid in the forward direction from the outer tank 5 to the inner tank 3 via the circulation piping 21. At this time, the first filter 55 collects foreign matter from the first processing liquid. In Figure 5, the forward direction in the circulation processing step (S3) is the path indicated by the solid arrow.

[0063] Following the circulation process (S3), the controller 73 performs the substrate processing process (S4) shown in Figure 3. In the substrate processing process (S4), the controller 73 controls the lifter 11. In the substrate processing process (S4), the controller 73 controls the lifter 11 to move the substrate W to the processing position. As a result, the lifter 11 immerses the substrate W in the first processing liquid, and the first processing liquid performs the processing on the substrate W. Once the processing of the substrate W by the first processing liquid is complete, the controller 73 controls the lifter 11, and the lifter 11 moves the substrate W to the standby position.

[0064] Furthermore, in this embodiment, as shown in Figure 4, during the circulation process (S3), the second-second supply valve 69, the second supply valve 87, and the second discharge valve 65 are in the open state. As a result, the second processing liquid flows in the reverse direction from the second processing liquid supply unit 47 to the second branch pipe 41.

[0065] Furthermore, in the substrate processing step (S4), as shown in Figures 4 and 5, the controller 73 controls the second-third supply valve 85, the second supply valve 87, and the second discharge valve 65 to open after closing the second-second supply valve 69. As a result, the third processing liquid flows in the reverse direction from the third processing liquid supply unit 48 to the second branch pipe 41 along the path indicated by the dashed arrow in Figure 5.

[0066] More specifically, the controller 73 controls the bellows pump 27 to pump the treatment liquid forward from the outer tank 5 to the inner tank 3 via the circulation piping 21, with the first circulation valves 49 and 51 open and the second circulation valves 67 and 71 closed. Furthermore, the controller 73 controls the second-second supply valve 69 to open for a predetermined period of time. This control causes the second treatment liquid to flow in the reverse direction from the second treatment liquid supply unit 47 to the second branch piping 41. Subsequently, the controller 73 closes the second-second supply valve 69 and controls the second-third supply valve 85 to open for a predetermined period of time. This control causes the third treatment liquid to flow in the reverse direction from the third treatment liquid supply unit 48 to the second branch piping 41. In other words, the controller 73 performs the filter cleaning process (second cleaning process) described later on the second filter 57 during the period when the first treatment liquid is circulating in the first branch piping 38. In other words, the controller 73 controls the first switching unit 25 to perform the second cleaning treatment on the second filter 57 during the period when the first treatment liquid is flowing in the forward direction through the first branch pipe 38.

[0067] In this embodiment, during the circulation process (S3), the second processing liquid supply unit 47 supplied the second processing liquid to the second filter 57. Also, during the substrate processing process (S4), the third processing liquid supply unit 48 supplied the third processing liquid to the second filter 57. However, the present invention is not limited thereto. During the circulation process (S3), the second processing liquid supply unit 47 and the third processing liquid supply unit 48 may sequentially supply the second processing liquid and the third processing liquid, respectively. Alternatively, during the substrate processing process (S4), the second processing liquid supply unit 47 and the third processing liquid supply unit 48 may sequentially supply the second processing liquid and the third processing liquid, respectively.

[0068] It is possible that the second filter 57, acting as a standby filter, is unused when the controller 73 first executes the circulation process (S3) and the substrate processing process (S4). In this case, the controller 73 does not need to perform the second cleaning process described above on the second filter 57, acting as a standby filter, during the circulation process (S3) and the substrate processing process (S4) immediately after the start of operation of the substrate processing apparatus 100. In this case, it is preferable that the controller 73 ensures that the first processing liquid or the third processing liquid is sealed in both the first filter 55 and the second filter 57 when the substrate processing apparatus 100 starts processing the substrate W. This allows the controller 73 to quickly start using the second filter 57 as a processing filter after the filter switching process described later.

[0069] The designer or user of the substrate processing apparatus 100 may appropriately set the predetermined period for opening the 2-2 supply valve 69 and the 1-2 supply valve 63 to be sufficient for cleaning the filter 53. The designer or user of the substrate processing apparatus 100 may appropriately set the predetermined period for opening the 2-3 supply valve 85 and the 1-3 supply valve 81 to be sufficient for filling the vicinity of the filter 53 with the 3rd processing liquid.

[0070] In the circulation process (S3), the controller 73 can detect the liquid delivery time, which is the time required for the bellows pump 27 to pump the liquid, based on the value detected by the stroke sensor 75 built into the bellows pump 27 described above.

[0071] After the substrate processing process (S4), the controller 73 performs the switching process (S5) shown in Figure 3. Specifically, in the switching process (S5), the controller 73 performs the lot processing determination process (S51), the switch condition determination process (S52), and the filter switching process (S53).

[0072] In the lot processing determination step (S51), the controller 73 determines whether the processing of one lot of substrate W has been completed. If the processing of a lot has not been completed (NO in S51), the controller 73 repeats step S41 until the processing of the lot is completed. If the processing of a lot has been completed (YES in S51), the controller 73 executes the switch condition determination step (S52).

[0073] In the switch condition determination step (S52), the controller 73 determines whether the switch condition is met, which is the condition for switching the processing filter and the standby filter from one of the first filter 55 and the second filter 57 to the other. If the switch condition is not met (NO in S52), the controller 73 skips the filter switching step (S53), step S6, and step S7 of step S5 and executes the termination confirmation step (S8). Details of the termination confirmation step (S8) will be described later.

[0074] If the switch condition is met (YES in S52), the controller 73 executes the filter switching process (S53) described later. The switch condition can be, for example, liquid delivery time, lot size, processing period, or recipe.

[0075] When the liquid delivery time is used as the switch condition, the liquid delivery time of the bellows pump 27, derived from the output of the stroke sensor 75, being equal to or greater than a predetermined threshold is used as the switch condition. When the lot number is used as the switch condition, for example, processing a predetermined number of lots of substrates W is used as the switch condition. When the processing period is used as the switch condition, for example, processing being performed over a predetermined period of time is used as the switch condition. When the recipe is used as the switch condition, for example, in a predetermined recipe for the operation of the substrate processing apparatus 100, a recipe is configured to switch the filter 53 used for filtering the first processing liquid before starting the processing of a lot.

[0076] In the lot processing discrimination process (S51) and the switch condition discrimination process (S52), the open / closed state of each valve is the same as in the substrate processing process (S3) and the circulation processing process (S4). The description of the switching process (S5) in Figure 4 is a timing chart showing the open / closed state of each valve when the filter switching process (S53) is executed.

[0077] In the filter switching process (S53), the controller 73 switches the circulation path through which the first treatment liquid flows in the forward direction within the circulation piping 21 by controlling the first switching unit 25. In this explanation, as shown in Figure 6, the controller 73 switches the circulation path through which the first treatment liquid flows in the forward direction from the first branch piping 38, which is equipped with the first filter 55, a treatment filter, to the second branch piping 41, which is equipped with the second filter 57, a standby filter. More specifically, as shown in Figures 4 and 6, the controller 73 switches the first circulation valves 49 and 51 from the open state to the closed state, and the second circulation valves 67 and 71 from the closed state to the open state.

[0078] In the filter switching process (S53), the controller 73 switches the first circulation valves 49 and 51 to the closed state and the second circulation valves 67 and 71 to the open state, and at the same time switches the processing filter and standby filter selected in the filter selection process (S1). More specifically, the controller 73 selects the first filter 55, which was selected as the processing filter in the filter selection process (S1), as the standby filter, and selects the second filter 57, which was selected as the standby filter in the filter selection process (S1), as the processing filter. The controller 73 temporarily stores the filter selection information for the filters 53 selected as the processing filter and standby filter, respectively, in the controller 73's memory 732.

[0079] After the switching process (S5), the controller 73 performs the filter preparation process (S6) shown in Figure 3. Specifically, in the filter preparation process (S6), the controller 73 performs the first processing liquid flow process (S61) and the first processing liquid temperature determination process (S62).

[0080] The first processing liquid flow process (S61) is performed simultaneously with or after the filter switching process (S53). In the filter switching process (S53), the controller 73 switches the circulation path through which the first processing liquid flows in the circulation piping 21 in the forward direction by controlling the first switching unit 25. Specifically, as described above, the controller 73 closes a pair of first circulation valves 49 and 51 and opens a pair of second circulation valves 67 and 71. As a result, the controller 73 causes the first processing liquid to flow into the second branch piping 41. The first processing liquid flow process (S61) initiates a period in which the first processing liquid flows in the forward direction into the second branch piping 41 by the controller 73 controlling the first switching unit 25. As a result, the first processing liquid flows to the second filter 57, which is a processing filter, along the path shown by the solid arrow in Figure 6. Furthermore, foreign matter is collected when the first processing liquid is filtered by the second filter 57.

[0081] After the first processing liquid flow process (S61), the controller 73 performs a first processing liquid temperature determination process (S62) to determine whether the temperature of the first processing liquid in the inner tank 3 has stabilized. Specifically, the controller 73 switches the filter 53 used for filtering the first processing liquid and then determines whether the temperature of the first processing liquid in the inner tank 3 has stabilized. Immediately after switching the filter 53, the temperature of the first processing liquid in the inner tank 3 becomes unstable because the third processing liquid in the filter 53 mixes with the first processing liquid. The controller 73 may determine that the temperature of the first processing liquid in the inner tank 3 is stable if, for example, the temperature of the first processing liquid in the inner tank 3 is within ±5°C of a reference temperature.

[0082] If the temperature of the first processing solution is unstable (NO in S62), the controller 73 repeats step S62 until the temperature of the first processing solution stabilizes. More specifically, if the controller 73 determines that the temperature of the first processing solution in the inner tank 3 is unstable, it may wait for a predetermined time and then re-determine the temperature of the first processing solution in the inner tank 3. In this case, the predetermined time may be, for example, 3 minutes. However, the method by which the controller 73 determines whether the temperature of the first processing solution in the inner tank 3 has stabilized, and the waiting time before re-determining if the temperature is unstable, are not limited to the above example. Also, if the temperature of the first processing solution has stabilized (YES in S62), the controller 73 executes the filter cleaning process (S7) described later.

[0083] After the filter preparation step (S6), the controller 73 performs the filter cleaning step (first cleaning process) (S7) shown in Figure 3 on the first filter, which is acting as a standby filter. Specifically, in the filter cleaning step (S7), the controller 73 performs the second treatment liquid supply step (S71) and the third treatment liquid supply step (S72).

[0084] In the second processing liquid supply step (S71), the controller 73 controls the second switching unit 26 to cause the second processing liquid to flow in the reverse direction into the first branch pipe 38, and to discharge liquid containing at least the first processing liquid from the discharge unit 45. Specifically, as shown in Figures 4 and 7, the controller 73 closes the first circulation valves 49 and 51 and opens the second circulation valves 67 and 71, so that while the first processing liquid is flowing into the second branch pipe 41, it opens the first supply valve 83, closes the second supply valve 87, opens the first discharge valve 61, and closes the second discharge valve 65. Furthermore, the controller 73 opens the first-to-second supply valve 63, opens the first supply valve 83, and opens the first discharge valve 61. As a result, the second processing liquid flows from the second processing liquid supply unit 47 to the first branch pipe 38 in the flow shown by the dashed arrow in Figure 7.

[0085] Furthermore, the first branch pipe 38 branches off from the discharge pipe 60 at the fifth branch point 38b, which is located upstream of the first filter 55. Therefore, in the second treatment liquid supply step (S71), the second treatment liquid flows from the second treatment liquid supply unit 47 to the first branch pipe 38 in the reverse direction, so that at least the liquid containing the first treatment liquid flows through the discharge pipe 60 and is discharged from the discharge unit 45. As a result, at least a portion of the first treatment liquid present inside the filter 53 is replaced by the second treatment liquid. Also, in the second treatment liquid supply step (S71), the second treatment liquid flows into the filter 53 in the reverse direction, which can remove clogging of the filter 53. Here, it is preferable to use a liquid suitable for removing clogging of the filter 53 as the second treatment liquid. It is most desirable that all of the first treatment liquid present inside the filter 53 be replaced by the second treatment liquid.

[0086] Furthermore, as described above, the circulation piping 21 is further equipped with a heater 31 that heats the first treatment liquid to a predetermined temperature. On the other hand, the second treatment liquid supply unit 47 supplies the second treatment liquid at room temperature. Room temperature here refers to, for example, a range of 5°C to 35°C.

[0087] For example, if the first processing solution is a processing solution containing sulfuric acid or phosphoric acid, it is preferable for the controller 73 to raise the temperature of the first processing solution to a temperature higher than room temperature using the heater 31. On the other hand, if the second processing solution is pure water or a processing solution containing hydrofluoric acid, it is preferable for the controller 73 to keep the second processing solution at room temperature. The substrate processing apparatus 100 can handle cases where the preferred temperatures for the first and second processing solutions differ in this way. Furthermore, as described above, by making the third processing solution a liquid that does not cause sudden boiling when mixed with the first processing solution, it is possible to suppress the occurrence of malfunctions when the circulation of the first processing solution in the circulation piping 21 is restarted. However, the second processing solution supply unit 47 does not necessarily have to supply the second processing solution at room temperature; it may also supply a high-temperature second processing solution.

[0088] Furthermore, immediately after the second processing liquid supply unit 47 supplies the second processing liquid to the first branch pipe 38, the area near the first filter 55 becomes filled with the second processing liquid. If the controller 73 were to restart the circulation of the first processing liquid in the circulation pipe 21 in this state, the first processing liquid and the second processing liquid would be mixed in the circulation pipe 21. At this time, for example, if the first processing liquid is at a high temperature and the boiling point of the second processing liquid is lower than the temperature of the first processing liquid, sudden boiling may occur in the second processing liquid, potentially causing problems such as damage to the piping of the inner tank 3.

[0089] Therefore, in the filter cleaning process (S7), the controller 73 performs the third treatment liquid supply process (S72). In the third treatment liquid supply process (S72), the controller 73 controls the second switching unit 26 to cause the third treatment liquid to flow in the reverse direction into the first branch pipe 38, and to discharge liquid containing at least the second treatment liquid from the discharge unit 45. Specifically, as shown in Figures 4 and 8, the controller 73 controls the first circulation valves 49 and 51 to be closed, the second circulation valves 67 and 71 to be open, the first-to-third supply valve 81 to be open, the first supply valve 83 to be open, and the first discharge valve 61 to be open. As a result, the third treatment liquid flows from the third treatment liquid supply unit 48 to the first branch pipe 38 in the flow shown by the dashed arrow in Figure 8.

[0090] The controller 73 opens the second circulation valves 67 and 71 and closes the first circulation valves 49 and 51, then opens the first-second supply valve 63 for a predetermined period of time, then closes the first-second supply valve 63 and opens the first-third supply valve 81 for a predetermined period of time. This allows for proper control of cleaning the first filter 55 during the period when the first treatment liquid is circulating in the second branch pipe 41. In other words, the controller 73 performs the first cleaning treatment on the first filter 55 during the period when the first treatment liquid is circulating in the second branch pipe 41.

[0091] Furthermore, the designer or user of the substrate processing apparatus 100 may appropriately set a period of time during which the controller 73 opens the first-second supply valve 63 and the first-third supply valve 81 that is sufficient to clean the filter 53.

[0092] In the third processing liquid supply step (S72), the third processing liquid flows from the third processing liquid supply unit 48 to the first filter 55 in the reverse direction, so that at least a liquid containing the second processing liquid is discharged from the discharge unit 45. As a result, at least a portion of the second processing liquid present inside the first filter 55 is replaced by the third processing liquid. As the third processing liquid flows through the first filter 55, the third processing liquid remains in the first filter 55. By replacing at least a portion of the second processing liquid remaining inside the first filter 55 with the third processing liquid, which does not cause bumping when mixed with the first processing liquid, the occurrence of malfunctions when the circulation of the first processing liquid in the circulation piping 21 is restarted can be suppressed. Most preferably, all of the second processing liquid inside the first filter 55 is replaced with the third processing liquid. In addition, in the third processing liquid supply step (S72), clogging of the first filter 55 can be removed by backflowing the third processing liquid into the first filter 55.

[0093] As described above, in the substrate processing apparatus 100, the upflow tube 19 is made of a material containing quartz. Such an upflow tube 19 is highly susceptible to damage if bumping occurs in the circulation piping 21. However, by making the third processing liquid a liquid that does not cause bumping even when mixed with the first processing liquid, it is possible to suppress the occurrence of damage to the upflow tube 19 when the circulation of the first processing liquid in the circulation piping 21 is restarted.

[0094] Furthermore, for example, if the components of the second processing liquid differ significantly from those of the first processing liquid, mixing the second and first processing liquids may cause a problem in which the components of the first processing liquid become unsuitable for processing the substrate W by the substrate processing tank 1. In the substrate processing apparatus 100, by making the third processing liquid a liquid that does not significantly change the components of the first processing liquid even when mixed with it, the occurrence of the above problem when the circulation of the first processing liquid in the circulation piping 21 is restarted can be suppressed.

[0095] In other words, the substrate processing apparatus 100 makes the second processing liquid suitable for cleaning the filter 53, and also makes the third processing liquid a liquid that does not cause problems even when mixed with the first processing liquid. Therefore, it becomes possible to clean the filter 53 appropriately and safely.

[0096] In particular, the first treatment solution may contain sulfuric acid and hydrogen peroxide. In this case, water is produced in the first treatment solution through the reaction and autodecomposition of hydrogen peroxide with sulfuric acid. As a result, the concentration of sulfuric acid in the first treatment solution decreases over time. By using sulfuric acid as the third treatment solution, the decreased concentration of sulfuric acid can be increased when the third treatment solution and the first treatment solution are mixed. Therefore, in such cases, the mixing of the third treatment solution and the first treatment solution brings the components of the first treatment solution circulating in the circulation piping 21 to a state suitable for treatment by the substrate treatment tank 1.

[0097] After the filter cleaning process (S7), the controller 73 performs a completion confirmation process (S8). During the filter cleaning process (S7), the controller 73 determines whether there are any lots to be processed next. If there are no lots to be processed next (NO in S8), the controller 73 terminates the operation of the substrate processing apparatus 100. If there are lots to be processed next (YES in S8), the controller 73 executes the aforementioned circulation process (S3) again. Note that since the filter cleaning process (S7) has been performed, the cleaning process for the standby filter described above is not performed in the circulation process (S3) and the substrate processing process (S4), which are executed again after the completion confirmation process (S8).

[0098] Next, the processing restart step (S9) will be explained using the case where there is a lot to be processed next (YES in S8) as an example. The processing restart step (S9) is the step of flowing the first processing liquid forward through the filter 53 after the filter cleaning step (S7). In other words, the processing restart step (S9) is the filter preparation step (S6) that is executed again when there is a lot to be processed next (YES in S8) in the processing restart step (S8). To avoid redundancy, the explanation of the lot processing determination step (S51) and switch condition determination step (S52) of the circulation processing step (S3), substrate processing step (S4), and switching processing step (S5), which are executed again when there is a lot to be processed next (YES in S8) in the processing restart step (S8), will be omitted here. The explanation will be based on the assumption that the second filter 57 is used as a processing filter in the circulation processing step (S3) and the substrate processing step (S4), the lot processing is completed in the lot processing determination step (S51), and the switch conditions are met in the switch condition determination step (S52) (YES in both S51 and S52).

[0099] In the filter switching process (S53), the controller 73 switches the circulation path through which the first treatment liquid flows in the forward direction within the circulation piping 21 by controlling the first switching unit 25. In this explanation, as shown in Figure 9, the controller 73 switches the circulation path through which the first treatment liquid flows in the forward direction from the second branch piping 41, which is equipped with the second filter 57, a treatment filter, to the first branch piping 38, which is equipped with the first filter 55, a standby filter. More specifically, as shown in Figures 4 and 9, the controller 73 switches the first circulation valves 49 and 51 from the closed state to the open state, and the second circulation valves 67 and 71 from the open state to the closed state.

[0100] Next, in the filter preparation step (S6), the controller 73 performs a second first processing liquid flow step (S61) and a first processing liquid temperature determination step (S62).

[0101] The controller 73 executes the first processing liquid circulation process (S61) after the filter switching process (S53). In the filter switching process (S53), the controller 73 switches the circulation path through which the first processing liquid flows in the circulation piping 21 in the forward direction by controlling the first switching unit 25. As a result, the first processing liquid flows to the first filter 55, which is a processing filter, along the path shown by the solid arrow in Figure 9. In other words, after the filter switching process (S53), the controller 73 circulates the first processing liquid in the forward direction to the first filter 55.

[0102] After the first processing liquid circulation process (S61), the controller 73 performs a first processing liquid temperature determination process (S62) to determine whether the temperature of the first processing liquid in the inner tank 3 has stabilized. In this embodiment, during the second first processing liquid circulation process (S61) and the first processing liquid temperature determination process (S62) described above, the first processing liquid was circulated in the forward direction through the first filter 55, which had undergone a filter cleaning process (S7). Therefore, the second first processing liquid circulation process (S61) and the first processing liquid temperature determination process (S62) described above correspond to the processing restart process (S9).

[0103] Furthermore, the content of the filter cleaning process (S7) performed by the controller 73 after the process restart process (S9) shown in Figure 4 is the same as described in the first explanation of the circulation process (S3) and the substrate processing process (S4) mentioned above. The completion confirmation process (S8) is also as described above.

[0104] As described above, in the substrate processing method of the substrate processing apparatus 100, the filter cleaning process (S7) is performed by the second processing liquid supply process (S71) and the third processing liquid supply process (S72). Furthermore, after the filter cleaning process (S7), the first processing liquid is circulated in the forward direction through the filter 53 in the processing restart process (S9). This suppresses problems caused by the mixing of the first processing liquid and the second processing liquid, as described above.

[0105] Furthermore, in the processing restart step (S9), the controller 73 controls the first switching unit 25 to initiate a period in which the first processing liquid flows forward through the first branch pipe 38. During this period, the controller 73 performs a filter cleaning step (S7) (second cleaning process) on the second filter 57. In the second cleaning process, the controller 73 controls the second switching unit 26 to cause the second processing liquid to flow backward through the second branch pipe 41, and discharges liquid containing at least the first processing liquid from the discharge unit 45. Subsequently, the controller 73 further controls the second switching unit 26 to cause the third processing liquid to flow backward through the second branch pipe 41, and discharges liquid containing at least the second processing liquid from the discharge unit 45. Furthermore, in the processing restart step (S9) after the second cleaning process, the controller 73 causes the first processing liquid to flow forward through the second branch pipe 41.

[0106] [Embodiment 2] Other embodiments of the present invention are described below. Embodiment 2 differs from Embodiment 1 in that it is equipped with a third processing liquid supply unit 48A instead of the third processing liquid supply unit 48 of Embodiment 1, and that the third processing liquid supply step (S152) is performed after the switch condition determination step (S151). For the sake of explanation, the same reference numerals are used for components having the same function as those described in the above embodiments, and their descriptions are not repeated.

[0107] Figure 10 is an overall diagram illustrating the schematic configuration of the substrate processing apparatus 200 according to Embodiment 2.

[0108] The third processing liquid supply unit 48A is a flow path connecting the circulation pipe 21 between the main filter 33 and the inner tank 3 to the filter 53. The third processing liquid supply unit 48A supplies the third processing liquid to the filter 53 by branching off from the circulation pipe 21. In the substrate processing apparatus 200, the third processing liquid is the first processing liquid that circulates in the circulation pipe 21. Therefore, the change in the state of the first processing liquid circulating in the circulation pipe 21 at the time when the circulation of the first processing liquid in the circulation pipe 21 is restarted after the cleaning process can be made very small. Thus, the time required from switching the filter 53 used for filtering the first processing liquid to restarting the processing of the substrate W can be made very small.

[0109] The third processing liquid supply unit 48A is equipped with a third supply valve 89. The third supply valve 89 controls the supply of the first processing liquid to the filter 53. The third processing liquid supply unit 48A supplies the first processing liquid to the filter 53 at a flow rate less than the flow rate of the first processing liquid overflowing from the inner tank 3 to the outer tank 5. This ensures that even when the first processing liquid circulating in the circulation piping 21 is supplied to the filter 53 during the cleaning process, the amount of first processing liquid necessary for processing in the substrate processing tank 1 can be reliably secured.

[0110] In the substrate processing apparatus 200, the controller 73 supplies the third processing liquid to the second filter 57 immediately before the end of the period during which the first processing liquid is circulated in the first branch pipe 38 by controlling the first switching unit 25 during the filter cleaning process. The controller 73 also supplies the third processing liquid to the first filter 55 immediately before the end of the period during which the first processing liquid is circulated in the second branch pipe 41 by controlling the first switching unit 25. In the substrate processing apparatus 100, which has a third processing liquid supply unit 48 instead of a third processing liquid supply unit 48A, the controller 73 may supply the third processing liquid to the filter 53 at the same timing.

[0111] As a result, the controller 73 ensures that, immediately before the end of the period in which the first treatment liquid is circulating in one of the two branch pipes (the first branch pipe 38 and the second branch pipe 41), the third treatment liquid supply unit 48 supplies the third treatment liquid to the filter 53 in the other branch pipe. Therefore, the amount of the third treatment liquid supplied to the filter 53 during the filter cleaning process can be kept to the absolute minimum.

[0112] In particular, in the substrate processing apparatus 200, as described above, the controller 73 supplies the first processing liquid circulating in the circulation pipe 21 to the filter 53 as the third processing liquid. Therefore, by minimizing the amount of the third processing liquid supplied to the filter 53, the amount of the first processing liquid circulating in the circulation pipe 21 can be minimized.

[0113] For example, the controller 73 supplies the second processing liquid to the standby filter 53 until the above-mentioned switch conditions are met, and then supplies the third processing liquid when the switch conditions are met. After that, the controller 73 terminates the supply of the third processing liquid and switches the branch piping through which the first processing liquid circulates to the branch piping containing the filter 53 that was previously in standby mode.

[0114] In this case, after the switch condition is met, the processing of one lot of substrate W does not need to be completed when the supply of the third processing solution is started. If the processing of one lot is not completed when the branch piping through which the first processing solution circulates is switched after the supply of the third processing solution has finished, the controller 73 will wait until the processing of that lot is completed. Also, if the processing of one lot is completed after the switch condition is met but before the supply of the third processing solution to the filter 53 has finished, the controller 73 may wait for the processing of the next lot until the switching of the branch piping through which the first processing solution circulates has finished. These switching of the branch piping through which the first processing solution circulates and waiting for the processing of the next lot are omitted in the flowchart described later.

[0115] (operation) The operation of the substrate processing apparatus 200 will be explained with reference to Figures 11 to 15. Figure 11 is a flowchart illustrating the operation of the substrate processing apparatus 200. Figures 12 to 15 illustrate the open and closed states of the valves provided in the first switching unit 25 and the second switching unit 26. In Figures 12 to 15, the valves in the first switching unit 25 and the second switching unit 26 that are in the closed state are shown in black.

[0116] In the substrate processing apparatus 200, the controller 73 executes a filter selection process (S1), a first processing liquid storage process (S2), a circulation processing process (S3), and a substrate processing process (S4). These processes are the same as those in the substrate processing apparatus 100, so their explanation is omitted. In the following explanation, we will use the case in which the first filter 55 is selected as the processing filter and the second filter 57 is selected as the standby filter in the filter selection process (S1) as an example. Therefore, in the substrate processing process (S4), the controller 73 opens the first circulation valves 49 and 51 and closes the second circulation valves 67 and 71, as shown in Figure 12.

[0117] However, in the initial circulation process (S3) and the substrate processing process (S4), only the second processing liquid is supplied to the second filter 57 in the reverse direction, and the third processing liquid is not supplied. In other words, by supplying the second processing liquid to the second filter 57, at least a portion of the first processing liquid is replaced, and the second processing liquid remains in the second filter 57. For this reason, in the substrate processing process (S4), as shown in Figure 12, the second-2 supply valve 69, the second supply valve 87, and the second discharge valve 65 are in the open state.

[0118] After the substrate processing process (S4), the controller 73 performs the switching process (S15) shown in Figure 11. Specifically, in the switching process (S15), the controller 73 performs the switch condition determination process (S151), the third processing liquid supply process (S152), and the filter switching process (S153).

[0119] In the switch condition determination step (S151), the controller 73 determines whether the switch condition has been met. If the switch condition has not been met (NO in S151), the controller 73 skips the third processing liquid supply step (S152) and the filter switching step (S153) of step S15, as well as step S6 and step S71, and executes the completion confirmation step (S8).

[0120] If the switch condition is met (YES in S151), the controller 73 performs the third processing liquid supply process (S152). In the third processing liquid supply process (S152), the controller 73 supplies the third processing liquid to the standby filter, the second filter 57, from the reverse direction. Specifically, as shown in Figure 13, the controller 73 opens the third supply valve 89, the second supply valve 87, and the second discharge valve 65. As a result, the third processing liquid flows from the third processing liquid supply unit 48A to the second branch pipe 41 in the flow indicated by the dashed arrow in Figure 13.

[0121] After the third processing liquid supply process (S152), the controller 73 performs the filter switching process (S153). In the filter switching process (S153), the controller 73 switches the circulation path in which the first processing liquid flows in the forward direction within the circulation piping 21 by controlling the first switching unit 25. In this explanation, as shown in Figure 14, the controller 73 switches the circulation path in which the first processing liquid flows in the forward direction from the first branch piping 38, which is equipped with the first filter 55, a processing filter, to the second branch piping 41, which is equipped with the second filter 57, a standby filter.

[0122] After the switching process (S15), the controller 73 performs the filter preparation process (S6) shown in Figure 11. The filter preparation process (S6) is the same as that of the substrate processing apparatus 100, so its explanation is omitted.

[0123] After the filter preparation step (S6), the controller 73 performs the second processing liquid supply step (S71). In the second processing liquid supply step (S71), the controller 73 supplies the second processing liquid to the standby filter, the first filter 55, from the reverse direction. Specifically, as shown in Figure 15, the controller 73 controls the first circulation valves 49 and 51 to be closed, the first-to-second supply valve 63 to be open, the first supply valve 83 to be open, and the first discharge valve 61 to be open. As a result, the second processing liquid flows from the second processing liquid supply unit 47 to the first branch pipe 38 in the flow indicated by the dashed arrow in Figure 15.

[0124] The controller 73 performs a completion confirmation step (S8) after the second processing liquid supply step (S71). The completion confirmation step (S8) is the same as that of the substrate processing apparatus 100, so its explanation is omitted.

[0125] The processing restart step (S9) is the same as in the substrate processing apparatus 100, so a detailed explanation is omitted. In the processing restart step (S9), the supply of the first processing liquid to the filter 53 in the forward direction is resumed. In Embodiment 2, in the filter switching step (S153), the standby filter is switched to the processing filter, and the first processing liquid is supplied in the forward direction to the second filter 57, which is sealed with liquid containing at least the second processing liquid.

[0126] As described above, in the substrate processing method of the substrate processing apparatus 200, the controller 73 performs the third processing liquid supply step (S152) to the standby filter after determining that the switch condition has been met in the switch condition determination step (S151). Furthermore, in the filter switching step (S153), the controller 73 performs the second processing liquid supply step (S71) to the filter 53 set as the standby filter, and then keeps it in standby mode without supplying the third processing liquid. As a result, as described above, the amount of the third processing liquid supplied to the filter 53 during the filter cleaning process can be kept to the absolute minimum.

[0127] [Embodiment 3] Further embodiments of the present invention are described below.

[0128] Figure 16 is an overall diagram illustrating the schematic configuration of a substrate processing apparatus 300 according to Embodiment 3. In the substrate processing apparatus 300, the filter 53 is provided downstream of the bellows pump 27. In addition, in the substrate processing apparatus 300, a first switching unit 25, a second switching unit 26, a first branch pipe 38, a second branch pipe 41, a second processing liquid supply unit 47, a third processing liquid supply unit 48, and a discharge unit 45 are also provided downstream of the bellows pump 27.

[0129] Furthermore, in the substrate processing apparatus 300, the filter 53 has the same pore diameter as the main filter 33 in the substrate processing apparatus 100 and the like. Moreover, the substrate processing apparatus 300 does not have a main filter 33. In other words, in the substrate processing apparatus 300, the filter 53 functions as the main filter.

[0130] In this substrate processing apparatus 300 as well, similar to the process shown in Embodiment 1, the occurrence of malfunctions can be suppressed by removing clogging of the filter 53 with the second processing liquid and then filling the vicinity of the filter 53 with the third processing liquid. Note that, similar to the substrate processing apparatus 200, the substrate processing apparatus 300 may be equipped with a third processing liquid supply unit 48A instead of the third processing liquid supply unit 48.

[0131] In the embodiments described above, the CPU 731 and memory 732 were shown as components of the controller 73. However, the substrate processing apparatus 100 may also have a memory (not shown) that stores information necessary for control by the controller 73, separate from the controller 73. Alternatively, the substrate processing apparatus 100 may be configured to communicate with an external memory that stores information necessary for control by the controller 73.

[0132] [Embodiment 4] Figure 17 is an overall diagram illustrating the schematic configuration of the substrate processing apparatus 400 according to Embodiment 4. The substrate processing apparatus 400 differs from the substrate processing apparatus 300 in that it has a substrate processing tank 1A instead of the substrate processing tank 1, and has a tank 90 for storing the first processing liquid.

[0133] The substrate processing apparatus 400 is equipped with a tank 90 for storing the first processing liquid in the circulation piping 21 at the location where the substrate processing tank 1 was installed in the substrate processing apparatus 300. In addition, the substrate processing apparatus 400 is equipped with a control valve 96 downstream of the first circulation valve 51, replacing the control valves 23 and 29 that were provided in the circulation piping 21 in the substrate processing apparatus 300.

[0134] The first processing liquid is supplied to the tank 90 from the first processing liquid supply unit 13. The first processing liquid stored in the tank 90 is pumped by the bellows pump 27 and circulates through the circulation piping 21 and the tank 90. ​​In Embodiment 4, the first processing liquid is sulfuric acid.

[0135] The control device 400 is controlled by the controller 73 to control the control valve 96 and the control valve 94 (described later) so that the processing is changed between a state in which the first processing liquid circulates in the circulation pipe 21 and a state in which a liquid containing the first processing liquid is discharged from the nozzle 93 (described later).

[0136] The circulation piping 21 branches off between the first circulation valve 51 and the control valve 96 to the SPM supply pipe 92, which is part of the substrate processing tank 1A. This allows sulfuric acid to be supplied to the SPM supply pipe 92 through the circulation piping 21. More specifically, both ends of the circulation piping 21 are connected to the SPM supply pipe 92. In other words, both ends of the circulation piping 21 are connected to the substrate processing tank 1A.

[0137] An H2O2 supply pipe 97 is connected to the SPM supply pipe 92. A control valve 99 is provided in the H2O2 supply pipe 97, and hydrogen peroxide (H2O2) is supplied from the H2O2 supply unit 98 to the SPM supply pipe 92 through the H2O2 supply pipe 97.

[0138] In this configuration, when the control valve 96 is closed, the first circulation valve 51 is open, and the control valve 99 is open, sulfuric acid and hydrogen peroxide are mixed in the SPM supply pipe 92 to produce SPM, which is then discharged from the nozzle 93 (described later) as a liquid containing the first processing liquid. SPM is a processing liquid produced by the chemical reaction between sulfuric acid and hydrogen peroxide, but in this embodiment, it is defined as a liquid containing the first processing liquid.

[0139] The substrate processing tank 1A is a so-called single-wafer processing unit that processes substrates W one at a time. In addition to the SPM supply pipe 92 described above, the substrate processing tank 1A is equipped with a spin chuck 91, a nozzle 93, a control valve 94, and a cup 95.

[0140] The spin chuck 91 holds the substrate W in a nearly horizontal position and rotates it. The SPM supply pipe 92 is connected at one end to the circulation pipe 21 and at the other end to the nozzle 93, and is a pipeline that supplies liquid containing the first processing liquid to the nozzle 93. The nozzle 93 supplies liquid containing the first processing liquid to the surface of the substrate W held by the spin chuck 91. The nozzle 93 is connected to the first processing liquid supply unit 13. A control valve 94 is provided on the SPM supply pipe 92 and controls the discharge of liquid containing the first processing liquid from the nozzle 93. A cup 95 is supplied from the nozzle 93 and prevents splashing of liquid containing the first processing liquid that has splashed from the substrate W. The cup 95 is connected to a drainage unit (not shown) and drains the processed liquid containing the first processing liquid from the substrate W.

[0141] (operation) Referring to Figure 3, the operation of the substrate processing apparatus 400 will be explained. In the following explanation, only the parts that differ from the operation of the substrate processing apparatus 100 will be described.

[0142] In the substrate processing apparatus 400, the controller 73 does not perform the first processing liquid storage process (S2), but starts the circulation processing process (S3) after the filter selection process (S1). In the circulation processing process (S3), the controller 73 controls control valves 96 and 94 instead of control valves 23 and 29 controlled by the substrate processing apparatus 100. The controller 73 opens control valve 96 and the first circulation valves 49 and 51, and closes control valve 94. As a result, the circulation of the first processing liquid is started via the circulation piping 21.

[0143] Next, in the substrate processing step (S4), the controller 73 of the substrate processing apparatus 400 controls control valves 96, 94, and 99 instead of the lifter 11 controlled by the substrate processing apparatus 100. The controller 73 closes control valve 96 and opens control valves 94 and 99. As a result, SPM is generated in the SPM supply pipe 92 and discharged onto the substrate W through the nozzle 93. When processing of the substrate W is complete, the controller 73 controls control valve 96 to open and control valves 94 and 99 to close. As a result, the discharge of SPM onto the substrate W is stopped.

[0144] In the substrate processing apparatus 400, after the first processing liquid circulation process (S61), the controller 73 performs the first processing liquid temperature determination process (S62). At this time, instead of determining the temperature of the first processing liquid in the inner tank 3, which was confirmed in the substrate processing apparatus 100, the controller 73 uses a temperature sensor (not shown) to determine whether the temperature of the first processing liquid in the circulation pipe 21 has stabilized.

[0145] Even in a substrate processing apparatus 400 equipped with such a substrate processing tank 1A, the filter 53 can be cleaned appropriately and safely while preventing damage to the components constituting the substrate processing apparatus 100. In the substrate processing apparatus 400, at least a portion of the second processing liquid present inside the filter 53 is replaced by the third processing liquid. This prevents the first processing liquid from boiling over in the circulation piping 21, thereby preventing damage to the circulation piping 21 and unintended discharge of the processing liquid from the nozzle 93.

[0146] [Embodiment 5] Figure 18 is an overall diagram illustrating the schematic configuration of the substrate processing apparatus 500 according to Embodiment 5. The substrate processing apparatus 500 differs from the substrate processing apparatus 100 in that it includes only the first filter 55 as the filter 53 and does not include the second filter 57.

[0147] In the substrate processing apparatus 500, the controller 73 may also perform the first cleaning process. That is, while the controller 73 is controlling the first switching unit 25 to allow the first processing liquid to flow in the forward direction through the second branch pipe 41, the controller 73 controls the second switching unit 26 to allow the second processing liquid to flow in the reverse direction through the first branch pipe 38, causing the liquid containing at least the first processing liquid to be discharged from the discharge unit 45. Subsequently, the controller 73 further controls the second switching unit 26 to allow the third processing liquid to flow in the reverse direction through the first branch pipe 38, causing the liquid containing at least the second processing liquid to be discharged from the discharge unit 45. Furthermore, after the first cleaning process, the controller 73 may allow the first processing liquid to flow in the forward direction through the first branch pipe 38 and the second and third processing liquids to flow in the reverse direction through the second branch pipe 41, or it may stop supplying the second and third processing liquids.

[0148] Furthermore, in the substrate processing apparatus 500, the controller 73 may control the second switching unit 26 to flow the second and third processing liquids in the second branch pipe 41 in the reverse direction during the period when the first processing liquid is flowing in the forward direction through the first branch pipe 38 by controlling the first switching unit 25. [Explanation of Symbols]

[0149] 1. 1A Substrate Processing Tank (Substrate Processing Unit) 3 Inner tank 5 Outer tank 21 Circulation piping 21a First branching point 21b Second branching point 25 First switching section 26. Second switching section 31 Heater 33 Main Filter 38 First branch pipe 38a Third branch point 38b Fifth branch point 41 Second branch pipe 41a Fourth branch point 41b Sixth branch point 45 Discharge part 47 Second processing liquid supply part 48, 48A Third processing liquid supply part 49, 51 First circulation valve 53 Filter 55 First filter 57 Second filter 60 Discharge pipe 61 First discharge valve 63 First - 2 supply valve 65 Second discharge valve 67, 71 Second circulation valve 69 Second - 2 supply valve 73 Controller (control unit) 81 First - 3 supply valve[[ID=4,2]] 85 Second - 3 supply valve 100, 200, 300, 400, 500 Substrate processing apparatus

Claims

1. A substrate processing tank that processes substrates with a liquid containing the first processing solution, The circulation piping includes a section connected to the substrate processing tank at both ends, which branches into two pipes: a first branch pipe and a second branch pipe. A filter for filtering the first processing solution, A second processing liquid supply unit supplies a second processing liquid having different components from the first processing liquid, A third processing liquid supply unit supplies a third processing liquid having different components from the second processing liquid, A discharge unit for discharging a liquid containing at least the first processing liquid or the second processing liquid, Controller and A first switching unit that switches whether the first processing liquid is flowed into the first branch pipe or into the second branch pipe, A second switching unit that switches whether the second processing liquid is flowed into the first branch pipe or the second branch pipe, and whether the third processing liquid is flowed into the first branch pipe or the second branch pipe, Equipped with, The filter is provided at least in the first branch pipe described above. The aforementioned controller, (1) During the period in which the first treatment liquid is flowing in the forward direction through the second branch pipe by controlling the first switching unit, the second treatment liquid is flowed in the reverse direction through the first branch pipe by controlling the second switching unit, causing the liquid containing at least the first treatment liquid to be discharged from the discharge unit, and thereafter, the third treatment liquid is flowed in the reverse direction through the first branch pipe by further controlling the second switching unit, causing the liquid containing at least the second treatment liquid to be discharged from the discharge unit, thereby performing a first cleaning process. (2) A substrate processing apparatus that, after the first cleaning process, flows the first processing liquid in the forward direction through the first branch pipe and flows the second processing liquid and the third processing liquid in the reverse direction through the second branch pipe, or stops the supply of the second processing liquid and the third processing liquid.

2. The circulation piping has a first branch point and a second branch point that branch into the first branch piping and the second branch piping, The first switching unit is, A pair of first circulation valves provided in the first branch piping, The system includes a pair of second circulation valves provided in the second branch piping, The filter is provided between a pair of the first circulation valves. The aforementioned controller, By opening the pair of first circulation valves and closing the pair of second circulation valves, the first processing liquid is flowed into the first branch pipe. The substrate processing apparatus according to claim 1, wherein the pair of first circulation valves are closed and the pair of second circulation valves are opened, thereby flowing the first processing liquid into the second branch pipe.

3. A first supply pipe connecting the second processing liquid supply unit and the third processing liquid supply unit to the first branch pipe, A second supply pipe connecting the second processing liquid supply unit and the third processing liquid supply unit to the second branch pipe, The system further comprises a discharge pipe connecting the first branch pipe and the second branch pipe to the discharge section, The first branch pipe has a third branch point that branches off from the first supply pipe between the filter and the first circulation valve on the downstream side in the forward direction. The second branch pipe has a fourth branch point that branches off from the second supply pipe between the filter and the second circulation valve on the downstream side in the forward direction. The first branch pipe has a fifth branch point on the upstream side in the forward direction, between the filter and the first circulation valve, which branches off from the discharge pipe. The second branch pipe has a sixth branch point on the upstream side in the forward direction, between the filter and the second circulation valve, where it branches off from the discharge pipe. The second switching unit is, A first supply valve located on the first supply piping side of the third branching point, A second supply valve located on the second supply piping side of the fourth branch point, The first discharge valve located on the discharge piping side of the fifth branching point, A second discharge valve located on the discharge piping side of the sixth branching point, Equipped with, The aforementioned controller, By opening the pair of first circulation valves and closing the pair of second circulation valves, while the first processing liquid is flowing through the first branch pipe, the first supply valve is closed, the second supply valve is open, the first discharge valve is closed, and the second discharge valve is open. The substrate processing apparatus according to claim 2, wherein the pair of first circulation valves are closed and the pair of second circulation valves are open, and while the first processing liquid is flowing through the second branch pipe, the first supply valve is opened, the second supply valve is closed, the first discharge valve is open, and the second discharge valve is closed.

4. The filter is further provided in the second branch pipe, The aforementioned controller, (1) During the period in which the first treatment liquid is flowing in the forward direction through the first branch pipe by controlling the first switching unit, the second treatment liquid is flowed in the reverse direction through the second branch pipe by controlling the second switching unit, causing the liquid containing at least the first treatment liquid to be discharged from the discharge unit, and thereafter, the second cleaning process is performed by further controlling the second switching unit to flow the third treatment liquid in the reverse direction through the second branch pipe, causing the liquid containing at least the second treatment liquid to be discharged from the discharge unit. (2) The substrate processing apparatus according to claim 1, wherein, after the second cleaning process, the first processing liquid is flowed in the second branch pipe in the forward direction, and the second processing liquid and the third processing liquid are flowed in the first branch pipe in the reverse direction, or the supply of the second processing liquid and the third processing liquid is stopped.

5. The substrate processing apparatus according to claim 1, wherein the first processing solution is a processing solution containing sulfuric acid, and the second processing solution is pure water.

6. The substrate processing apparatus according to claim 1, wherein the first processing solution is phosphoric acid and the second processing solution is a processing solution containing hydrofluoric acid.

7. The circulation piping includes a heater for heating the first processing liquid to a predetermined temperature. The substrate processing apparatus according to claim 1, wherein the second processing liquid supply unit supplies the second processing liquid at room temperature.

8. The third processing liquid supply unit supplies the third processing liquid to the filter by branching off from the circulation piping. The substrate processing apparatus according to claim 1, wherein the third processing liquid is the first processing liquid circulating in the circulation piping.

9. The substrate processing tank comprises an inner tank for storing the first processing liquid supplied from the circulation piping, and an outer tank for storing the first processing liquid that overflows from the inner tank. One end of the aforementioned circulation piping is connected to the outer tank, and the other end is connected to the inner tank. The substrate processing apparatus according to claim 8, wherein the third processing liquid supply unit supplies the third processing liquid to the filter at a flow rate less than the flow rate of the first processing liquid overflowing from the inner tank to the outer tank.

10. The aforementioned controller, In the second cleaning process, immediately before the end of the period during which the first treatment liquid is circulated in the first branch pipe by controlling the first switching unit, the third treatment liquid is flowed in the reverse direction through the second branch pipe. The substrate processing apparatus according to claim 4, wherein, in the first cleaning process, the third processing liquid is flowed in the reverse direction through the first branch pipe immediately before the end of the period during which the first processing liquid is circulated through the second branch pipe by controlling the first switching unit.

11. The second switching unit is, A first-to-second supply valve switches whether or not the second processing liquid flows from the second processing liquid supply unit to the first branch pipe. A first to third supply valve switches whether or not the third processing liquid flows from the third processing liquid supply unit to the first branch pipe. A second-2 supply valve that switches whether or not the second processing liquid flows from the second processing liquid supply unit to the second branch pipe, and The system further includes a second-to-third supply valve that switches whether or not the third processing liquid flows from the third processing liquid supply unit to the second branch pipe, The aforementioned controller, With the first circulation valve open, the second circulation valve closed, and the second supply valve open, the second-2 supply valve is opened for a predetermined period of time, and then the second-3 supply valve is opened for a predetermined period of time. The substrate processing apparatus according to claim 3, wherein, with the second circulation valve open, the first circulation valve closed, and the first supply valve open, the control is performed to open the first-2 supply valve for a predetermined period of time, and then to open the first-3 supply valve for a predetermined period of time.

12. The circulation piping further includes a main filter located downstream of the filter, The substrate processing apparatus according to claim 1, wherein the filter is a prefilter, and the pore diameter of the main filter is smaller than the pore diameter of the prefilter.

13. The substrate processing apparatus according to claim 1, wherein the member through which the first processing liquid passes in the substrate processing tank is made of a material containing quartz.

14. A substrate processing tank that processes substrates with a liquid containing the first processing solution, The circulation piping includes a section connected to the substrate processing tank at both ends, which branches into two pipes: a first branch pipe and a second branch pipe. A filter for filtering the first processing solution, A second processing liquid supply unit supplies a second processing liquid having different components from the first processing liquid, A third processing liquid supply unit supplies a third processing liquid having different components from the second processing liquid, A discharge unit for discharging a liquid containing at least the first processing liquid or the second processing liquid, A first switching unit that switches whether the first processing liquid is flowed into the first branch pipe or into the second branch pipe, A second switching unit that switches whether the second processing liquid is flowed into the first branch pipe or the second branch pipe, and whether the third processing liquid is flowed into the first branch pipe or the second branch pipe, A substrate processing method in a substrate processing apparatus comprising, The filter is provided at least in the first branch pipe described above. (1) During the period in which the first treatment liquid is flowing in the forward direction through the second branch pipe by controlling the first switching unit, the second treatment liquid is flowed in the reverse direction through the first branch pipe by controlling the second switching unit, causing the liquid containing at least the first treatment liquid to be discharged from the discharge unit, and thereafter, the third treatment liquid is flowed in the reverse direction through the first branch pipe by further controlling the second switching unit, causing the liquid containing at least the second treatment liquid to be discharged from the discharge unit, thereby performing a first cleaning process. (2) A substrate processing method comprising, after the first cleaning process, flowing the first processing liquid in the forward direction through the first branch pipe and flowing the second processing liquid and the third processing liquid in the reverse direction through the second branch pipe, or stopping the supply of the second processing liquid and the third processing liquid.

15. In a substrate processing tank, a substrate processing step is performed in which the substrate is processed with a liquid containing a first processing liquid, A circulation processing step in which a first processing liquid flowing in the forward direction within a circulation pipe is filtered by a filter provided in at least the first branch pipe of a circulation pipe that branches into two pipes, a first branch pipe and a second branch pipe, with both ends connected to the substrate processing tank, During the period in which the first processing liquid is flowing in the forward direction through the second branch pipe by controlling a first switching unit that switches whether to flow the first processing liquid through the first branch pipe or the second branch pipe, the second processing liquid is flowed in the reverse direction through the first branch pipe by controlling a second switching unit that switches whether to flow a second processing liquid having different components from the first processing liquid through the first branch pipe or the second branch pipe, and whether to flow a third processing liquid having different components from the second processing liquid through the first branch pipe or the second branch pipe, thereby performing a first cleaning process in which the second processing liquid is flowed in the reverse direction through the first branch pipe, and the liquid containing at least the first processing liquid is discharged from a discharge unit that discharges liquid containing at least the first processing liquid or the second processing liquid, and thereafter, by further controlling the second switching unit, the third processing liquid is flowed in the reverse direction through the first branch pipe, and the liquid containing at least the second processing liquid is discharged from the discharge unit, A substrate processing method comprising a processing restart step of restarting the circulation of the first processing liquid through the first branch pipe after the first cleaning process.

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