Method for calculating washing time

Abstract

To calculate an appropriate cleaning time of a pipe or the like.SOLUTION: A cleaning time calculation method comprises: a step of satisfying a pipe line for supplying a processing liquid of a processing unit for processing a substrate with a cleaning liquid; a step of measuring a first content amount change as a time change of an impurity content amount in the cleaning liquid generated until a first time in the pipe line and a second content amount change as a time change of an impurity content amount in the cleaning liquid generated until a second time after the first time in the pipe line; and a step of calculating the cleaning time for the pipe line on the basis of a difference between the first content amount change and the second content amount change.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The technology disclosed in this specification relates to calculating the cleaning time related to substrate processing. The substrates to be processed include, for example, semiconductor wafers, glass substrates for liquid crystal display devices, substrates for flat panel displays (FPDs) such as organic EL (electroluminescence) display devices, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, glass substrates for photomasks, ceramic substrates, substrates for field emission displays (that is, FEDs), or substrates for solar cells, etc.

Background Art

[0002] Conventionally, resin members have been used in the configurations such as piping of substrate processing apparatuses (for example, refer to Patent Document 1).

[0003] When starting up the apparatus or replacing parts of the substrate processing apparatus as described above, substrate processing is started after each component is cleaned.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Even after cleaning is performed as described above, impurities remaining inside the resin member etc. may flow out into the processing liquid, and it is important that the cleaning is properly performed. [[ID=4**1]]

[0006] However, it is difficult to predict the presence or absence of impurities that flow out over time based only on the measurement of the impurity content immediately after cleaning. On the other hand, an excessively long cleaning time will reduce the efficiency of substrate processing.

[0007] The technology disclosed in this specification was developed in consideration of the problems described above, and is a technology for calculating the appropriate cleaning time for piping and other components in substrate processing. [Means for solving the problem]

[0008] A first aspect of the technology disclosed in this specification, a method for calculating cleaning time, comprises the steps of: filling a piping line for supplying a processing liquid to a processing unit for processing a substrate with cleaning liquid; measuring a first content change, which is the change in the amount of impurities in the cleaning liquid over time up to a first time in the piping line; and measuring a second content change, which is the change in the amount of impurities in the cleaning liquid over time up to a second time, which is a time later than the first time in the piping line; and measuring the first content change and the second content change toni based on Until the time course of the calculated change in content falls below a predetermined threshold. , cleaning time for the aforementioned piping line as It includes a calculation process.

[0009] A second aspect of the technology disclosed in this specification, which is a method for calculating cleaning time, relates to the first aspect of the method for calculating cleaning time, wherein the step of filling the piping line with the cleaning liquid is a step of filling the piping line with the cleaning liquid after draining the cleaning liquid that had already filled the piping line.

[0010] A third aspect of the technology disclosed in this specification, which is a method for calculating cleaning time, relates to the first or second aspect of the method for calculating cleaning time, wherein the first content change and the second content change are changes in the content of particles contained in the cleaning liquid.

[0011] A fourth aspect of the technology disclosed in this specification, which is a method for calculating cleaning time, relates to a method for calculating cleaning time that is any one of the first to third aspects, wherein the cleaning solution is a chemical solution for processing the substrate.

[0012] A fifth aspect of the technology disclosed in this specification, which is a method for calculating cleaning time, relates to a method for calculating cleaning time that is any one of the first to fourth aspects, wherein the cleaning solution is isopropyl alcohol.

[0013] A sixth aspect of the technology disclosed in this specification, which is a method for calculating the cleaning time, relates to a cleaning time calculation method which is any one of the first to fifth aspects, wherein the steps of measuring the first content change and the second content change are repeated until the cleaning time is calculated.

[0014] A seventh aspect of the technology disclosed in this specification, a method for calculating cleaning time, relates to a method for calculating cleaning time that is any one of the first to sixth aspects, and further comprises the step of starting the processing of the substrate in the processing unit after the calculated cleaning time has elapsed.

[0015] An eighth aspect of the technology disclosed in this specification, a method for calculating cleaning time, relates to any one of the first to seven aspects of a method for calculating cleaning time, wherein the piping line includes a resin tube.

[0016] A ninth aspect of the technology disclosed in this specification, a method for calculating cleaning time, relates to a method for calculating cleaning time that is any one of the first to eight aspects, wherein the piping line includes in part a measuring line for which the cleaning time is to be calculated, and the step of measuring the first content change and the second content change comprises the steps of draining the cleaning liquid from the piping line located downstream of the measuring line, discharging the cleaning liquid from the measuring line onto the substrate, drying the substrate onto which the cleaning liquid has been discharged, and detecting impurities on the dried substrate. [Effects of the Invention]

[0017] According to at least a first aspect of the technology disclosed in this specification, an appropriate cleaning time for the measurement line can be calculated based on the time course of changes in the impurity content.

[0018] In addition, the objects, features, aspects, and advantages related to the technology disclosed in the specification of the present application will become clearer with the following detailed description and the accompanying drawings.

Brief Description of the Drawings

[0019] [Figure 1] It is a plan view schematically showing an example of the configuration of a substrate processing apparatus according to an embodiment. [Figure 2] It is a diagram showing an example of the configuration of the control unit whose example was shown in FIG. 1. [Figure 3] It is a side view schematically showing an example of a processing unit and its related configuration in a substrate processing apparatus according to an embodiment. [Figure 4] It is a flowchart showing the operation in the processing unit among the operations of the substrate processing apparatus. [Figure 5] It is a diagram conceptually showing an example of the state where impurities mixed in the resin member used in the piping line are mixed into the processing liquid. [Figure 6] It is a diagram conceptually showing an example of the state where impurities mixed in the resin member used in the piping line are mixed into the processing liquid. [Figure 7] It is a diagram showing an example of the timing for measuring the impurity content of the cleaning liquid in the measurement line in order to calculate the cleaning time of the measurement line. [Figure 8] It is a diagram showing the experimental results evaluating the change in the impurity content in the cleaning liquid. [Figure 9] It is a diagram plotting the slopes of the respective dotted lines shown in the figure. [Figure 10] It is a side view schematically showing an example of a processing unit and its related configuration according to the present embodiment.

Modes for Carrying Out the Invention

[0020] The embodiments will be described below with reference to the attached drawings. In the following embodiments, detailed features will be shown for the purpose of explaining the technology, but these are illustrative, and not all of them are necessarily essential features for the embodiments to be implementable.

[0021] Please note that the drawings are for illustrative purposes only, and for the sake of clarity, some components may be omitted or simplified as appropriate. Furthermore, the relative sizes and positions of components shown in different drawings are not necessarily accurately represented and may be modified as appropriate. In addition, hatching may be added to drawings other than cross-sectional views, such as plan views, to facilitate understanding of the embodiment.

[0022] Furthermore, in the following explanations, similar components will be denoted by the same symbols, and their names and functions will also be the same. Therefore, detailed explanations of them may be omitted to avoid redundancy.

[0023] Furthermore, in the descriptions contained in this specification, when a certain component is described as "equipped with," "includes," or "has," unless otherwise specified, it is not an exclusive expression that excludes the existence of other components.

[0024] Furthermore, even if ordinal numbers such as "first" or "second" are used in the descriptions contained herein, these terms are used for convenience to facilitate understanding of the embodiments, and the contents of the embodiments are not limited to the order that may result from these ordinal numbers.

[0025] Furthermore, even if terms such as "top," "bottom," "left," "right," "side," "bottom," "front," or "back" are used in the descriptions of this specification to indicate a specific position or direction, these terms are used for convenience to facilitate understanding of the embodiments and are not related to the actual position or direction in which the embodiments are carried out.

[0026] Furthermore, in the descriptions contained herein, when a "top surface of..." or "bottom surface of..." is used, it includes not only the top surface or bottom surface of the component in question itself, but also the state in which other components are formed on the top surface or bottom surface of the component in question. That is, for example, when it is stated that "B is provided on the top surface of A", this does not preclude the presence of another component "C" between A and B.

[0027] <Embodiment> The configuration of the substrate processing apparatus and the method for calculating the cleaning time according to this embodiment will be described below.

[0028] <About the configuration of the substrate processing unit> Figure 1 is a schematic plan view showing an example of the configuration of a substrate processing apparatus 1 according to this embodiment. The substrate processing apparatus 1 comprises a load port 601, an indexer robot 602, a center robot 603, a control unit 90, and at least one processing unit 600 (four processing units in Figure 1).

[0029] The processing unit 600 is a single-wafer device that can be used for substrate processing, and specifically, it is a device that removes organic matter adhering to the substrate W. The organic matter adhering to the substrate W is, for example, a used resist film. This resist film is, for example, one that was used as an implantation mask for the ion implantation process.

[0030] The processing unit 600 may have a chamber 180. In that case, by controlling the atmosphere inside the chamber 180 with the control unit 90, the processing unit 600 can perform substrate processing in a desired atmosphere.

[0031] The control unit 90 can control the operation of each component in the substrate processing apparatus 1 (such as the spin motor 10D, actuator 22C, and valve 25, which will be described later). Carrier C is a container for housing substrates W. Load port 601 is a container holding mechanism that holds multiple carriers C. Indexer robot 602 can transport substrates W between load port 601 and substrate mounting section 604. Center robot 603 can transport substrates W between substrate mounting section 604 and processing unit 600.

[0032] With the above configuration, the indexer robot 602, the substrate mounting unit 604, and the center robot 603 function as a transport mechanism that transports the substrate W between the respective processing unit 600 and the load port 601.

[0033] The unprocessed substrate W is removed from the carrier C by the indexer robot 602. The unprocessed substrate W is then transferred to the center robot 603 via the substrate mounting unit 604.

[0034] The central robot 603 loads the unprocessed substrate W into the processing unit 600. The processing unit 600 then processes the substrate W.

[0035] The processed substrates W in the processing unit 600 are removed from the processing unit 600 by the center robot 603. The processed substrates W are then passed through other processing units 600 as needed, and then transferred to the indexer robot 602 via the substrate mounting unit 604. The indexer robot 602 loads the processed substrates W into the carrier C. Through this process, the substrates W are processed.

[0036] Figure 2 shows an example of the configuration of the control unit 90 shown in Figure 1. The control unit 90 may be composed of a general computer having electrical circuits. Specifically, the control unit 90 includes a central processing unit (i.e., CPU) 91, read-only memory (i.e., ROM) 92, random access memory (i.e., RAM) 93, recording device 94, input unit 96, display unit 97, and communication unit 98, and a bus line 95 connecting them to each other.

[0037] ROM92 stores the basic program. RAM93 is used as a workspace for the CPU91 when performing predetermined processing. The recording device94 is composed of a non-volatile recording device such as flash memory or a hard disk drive. The input unit96 is composed of various switches or a touch panel and receives input setting instructions such as processing recipes from the user. The display unit97 is composed of, for example, a liquid crystal display device and lamps and displays various information under the control of the CPU91. The communication unit98 has a data communication function via a local area network (LAN) or the like.

[0038] The recording device 94 has multiple modes pre-configured for controlling each of the configurations in the substrate processing apparatus 1 shown in Figure 1. When the CPU 91 executes the processing program 94P, one of the above multiple modes is selected, and each configuration is controlled in that mode. The processing program 94P may be recorded on an external recording medium. Using this recording medium, the processing program 94P can be installed in the control unit 90. Furthermore, some or all of the functions performed by the control unit 90 do not necessarily have to be implemented by software, but may be implemented by hardware such as dedicated logic circuits.

[0039] <About the processing unit> Figure 3 is a schematic side view showing an example of the processing unit 600 and its related configuration in the substrate processing apparatus 1 according to this embodiment.

[0040] The processing unit 600 includes a spin chuck 10 that holds a single substrate W in a substantially horizontal position and rotates the substrate W around a vertical rotation axis Z1 passing through the center of the substrate W, a processing liquid nozzle 20 that discharges processing liquid 120 onto the upper surface of the substrate W, a processing liquid supply source 29 that supplies processing liquid 120 to the processing liquid nozzle 20, a pipe 28 for supplying processing liquid 120 from the processing liquid supply source 29 to the processing liquid nozzle 20, valves 25 and 26 provided on the pipe 28 and for adjusting the amount of processing liquid 120 supplied through the pipe 28, a nozzle arm 22 to which the processing liquid nozzle 20 is attached, a particle detector 702 directed towards the upper surface of the substrate W, and a cylindrical processing cup 12 that surrounds the spin chuck 10 around the rotation axis Z1 of the substrate W.

[0041] The processing solution 120 includes chemicals used for substrate processing and cleaning solutions for cleaning the substrate, and may contain at least one of the following: sulfuric acid, acetic acid, nitric acid, hydrochloric acid, hydrofluoric acid, aqueous ammonia, distilled water (DIW), hydrogen peroxide, organic acids (e.g., citric acid or oxalic acid), organic alkalis (e.g., tetramethylammonium hydroxide (TMAH)), IPA (isopropyl alcohol), surfactants, and corrosion inhibitors. Examples of chemical solutions obtained by mixing these include a mixed solution of sulfuric acid and hydrogen peroxide (SPM), a mixed solution of ammonia and hydrogen peroxide (SC1), and dilute hydrofluoric acid (DHF) obtained by diluting hydrofluoric acid (HF) with distilled water.

[0042] A portion of the piping 28 corresponds to the measurement line 28A. Valve 25 is located upstream of the measurement line 28A. Valve 26 is located downstream of the measurement line 28A. In other words, the measurement line 28A is the portion of the piping 28 between valves 25 and 26. The measurement line 28A is the portion to be measured for the calculation of the cleaning time described later, and may be a portion that can be replaced, for example, by replacing parts.

[0043] The processing liquid supply source 29, the piping 28 (including the measurement line 28A), the valves 25 and 26, and the processing liquid nozzle 20 described above are referred to as the piping line for supplying the processing liquid 120 to the substrate W.

[0044] For example, fluororesins such as polytetrafluoroethylene (PTFE) and perfluoroalkoxyalkane (PFA) are used in the parts of the piping line that come into contact with the treatment liquid 120. The piping 28 is, for example, a resin tube.

[0045] The particle detector 702 includes an imaging unit, such as a camera, directed towards the top surface of the substrate W, and captures an image of the top surface of the substrate W under the control of the control unit 90. The particle detector 702 may include, for example, a time delay integration (TDI) camera. The obtained image data is then output to the control unit 90, and image analysis is performed to detect whether any impurities such as particles remain on the top surface of the substrate W. A machine learning algorithm may be applied to this image analysis.

[0046] The spin chuck 10 comprises a disc-shaped spin base 10A facing the lower surface of a substrate W in a substantially horizontal position, a plurality of chuck pins 10E that grip the substrate W from the outer circumference of the spin base 10A, a rotating shaft 10C extending downward from the center of the spin base 10A, and a spin motor 10D that rotates the substrate W held by the spin base 10A by rotating the rotating shaft 10C. The plurality of chuck pins 10E are arranged at equal intervals along the circumference of the circular substrate W. Alternatively, a suction-type chuck that vacuum-suctions the lower surface of the substrate W may be used instead of the spin chuck 10.

[0047] The nozzle arm 22 comprises an arm portion 22A, a shaft 22B, and an actuator 22C. The actuator 22C adjusts the angle of the shaft 22B around its axis. One end of the arm portion 22A is fixed to the shaft 22B, and the other end of the arm portion 22A is positioned away from the axis of the shaft 22B. A processing liquid nozzle 20 is attached to the other end of the arm portion 22A. By adjusting the angle of the shaft 22B with the actuator 22C, the processing liquid nozzle 20 is configured to swing in the radial direction of the substrate W. Note that the direction of movement of the processing liquid nozzle 20 due to the swing only needs to have a component in the radial direction of the substrate W, and does not need to be strictly parallel to the radial direction of the substrate W.

[0048] Furthermore, although the processing unit 600 has only one nozzle in the example above, it may also be provided with additional nozzles for dispensing the processing liquid onto the substrate W.

[0049] <About the operation of the substrate processing unit> Next, an example of the operation of the substrate processing apparatus 1 will be explained with reference to Figure 4. Figure 4 is a flowchart showing the operation of the processing unit 600 within the operation of the substrate processing apparatus 1.

[0050] The indexer robot 602 transports the substrate W from the carrier C in the load port 601 to the substrate mounting section 604. The center robot 603 transports the substrate W from the substrate mounting section 604 to one processing unit 600. The processing unit 600 processes the substrate W. The center robot 603 transports the substrate W from the processing unit 600 back to the substrate mounting section 604. The indexer robot 602 transports the substrate W from the substrate mounting section 604 back to the carrier C in the load port 601.

[0051] In the substrate processing in the processing unit 600, first, a chemical solution is supplied to the upper surface of the substrate W from the processing liquid nozzle 20 to perform a predetermined chemical treatment (step ST01 in Figure 4). Then, pure water (DIW) or the like is supplied to the upper surface of the substrate W from the processing liquid nozzle 20 to perform a rinsing treatment (step ST02 in Figure 4). Furthermore, the pure water is replaced with IPA (isopropyl alcohol) supplied from the processing liquid nozzle 20, and the substrate W is rotated at high speed in the spin chuck 10 to shake off the IPA. This dries the substrate W (step ST03 in Figure 4).

[0052] In the chemical treatment of the substrate processing described above, a predetermined processing solution is discharged from the processing solution nozzle 20 onto the upper surface of the substrate W, which is held in the spin chuck 10 and rotating. The type of processing solution discharged from the processing solution nozzle 20, the amount discharged, the concentration, the temperature, and the discharge timing are controlled by the control unit 90 based on a processing recipe recorded in the recording device 94 or the like.

[0053] <Regarding impurities in piping lines> As described above, fluororesin is used in the parts of the piping line that come into contact with the treatment liquid 120. Since this resin component contains impurities (particles including metal dust) that were introduced during the manufacturing process, it is important to remove these impurities before processing the substrate.

[0054] Figures 5 and 6 conceptually illustrate an example of how impurities present in resin components used in piping lines are mixed into the treatment liquid 120.

[0055] As shown in Figure 5, the resin member 101 is composed of multiple lumps of resin 102. Each lump of resin 102 is composed of a single polymer molecule or multiple polymer molecules. Impurities 103 are attached to the surface of the resin member 101. The impurities 103 are present not only on the surface of the resin member 101 but also inside the resin member 101.

[0056] In the following, impurities 103 adhering to the surface of the resin member 101 will be referred to as impurities 103A, and impurities 103 present inside the resin member 101 will be referred to as impurities 103B. Impurities 103B are mainly present between the lumpy resin 102s.

[0057] The impurities 103 enter the interior of the resin member 101, for example, when the resin member 101 is formed by injection molding. The impurities 103 are also called particles and are, for example, organic matter.

[0058] When the resin member 101 is cleaned with a cleaning solution 120A at room temperature, impurities 103A adhering to the surface of the resin member 101 can be removed by dissolving them into the cleaning solution 120A or by flowing them into the cleaning solution 120A, as shown in the example in Figure 6.

[0059] However, as shown in the example in Figure 6, at least some of the impurities 103B present inside the resin member 101 remain inside the resin member 101 without being removed. These remaining impurities 103B gradually dissolve or leach into the cleaning solution 120A or the chemical solution used for substrate processing over time.

[0060] To prevent impurities from entering the processing solution 120, thorough cleaning of the piping lines is necessary. However, it is difficult to determine how long the cleaning should take, and sometimes the cleaning is performed for longer than necessary.

[0061] This embodiment describes a method for effectively calculating the cleaning time of a piping line.

[0062] <Regarding the calculation of washing time> In this embodiment, the case of calculating the cleaning time of the measurement line 28A shown in Figure 3 among the piping lines will be explained with reference to Figure 3.

[0063] Figure 7 shows an example of the timing for measuring the impurity content of the cleaning solution in measurement line 28A in order to calculate the cleaning time of measurement line 28A. In Figure 7, the horizontal axis represents the length of time that measurement line 28A is filled with cleaning solution and immersed. Furthermore, the immersion time is not limited to cases where measurement line 28A is continuously immersed, but may be interrupted.

[0064] First, valves 25 and 26 are opened to allow cleaning fluid to flow from the processing fluid supply source 29, filling the piping 28, including the measurement line 28A, with cleaning fluid.

[0065] Next, valves 25 and 26 are closed to drain the cleaning liquid from the piping 28 and the processing liquid nozzle 20 located downstream of valve 26 into a standby pod or the like (not shown). The timing of this draining can be any time before the timing of discharging the cleaning liquid from the measurement line 28A, which will be described later.

[0066] Next, when the measurement line 28A has been filled with cleaning solution and the substrate W has been immersed for a predetermined time, the valve 26 is opened to discharge the cleaning solution that filled the measurement line 28A onto the upper surface of the substrate W. The substrate W from which the cleaning solution is discharged may be a test substrate or the like, used for calculating the cleaning time of the measurement line 28A.

[0067] Here, in addition to 0 hours (i.e., when the cleaning solution is discharged immediately after the start of immersion), at least two other immersion times (for example, x hours and y hours) must be set for the immersion time within the measurement line 28A.

[0068] In this embodiment, after flushing (preliminary discharge) the processing liquid 120 in the piping 28, the immersion times are set in the order of 0 hours, x hours, and y hours. Then, after flushing the piping 28 again, the immersion times are set in the order of 0 hours, x hours, and y hours, and so on, repeating the flushing and immersion process. When setting the immersion times of x hours and y hours, the cleaning liquid in the measurement line 28A is discharged each time. Note that if it is possible to detect the impurity content of the cleaning liquid in the measurement line 28A, flushing and draining are not essential, but performing flushing and draining makes it easier to manage each immersion time.

[0069] The impurity content of each of the cleaning solutions discharged onto the upper surface of the substrate W at a predetermined time is detected. The detection of impurity content is repeated until the cleaning time, as described later, is calculated.

[0070] Specifically, the substrate W from which the cleaning solution has been discharged is rotated at high speed in the spin chuck 10 to perform a drying process. After the drying process, any impurities (particles) remaining on the upper surface of the substrate W are detected by the particle detector 702. From the perspective of performing the above drying process, IPA (isopropyl alcohol) can be used as the cleaning solution.

[0071] Figure 8 shows the experimental results evaluating the change in impurity content in the cleaning solution. In Figure 8, the vertical axis represents the impurity content (relative value) in the cleaning solution, and the horizontal axis represents the immersion time [h] of measurement line 28A.

[0072] Furthermore, in Figure 8, the impurity content measured in the order of 0 hours, x hours, and y hours after flushing the treatment solution 120 is considered one set, and the measurement results of the impurity content in the same set (specifically, the measurement result at 0 hours and the measurement result at y hours) are connected by a dotted line. The slope of this dotted line corresponds to the change in impurity content (change in content) over time in the washing solution.

[0073] In Figure 8, the white circles indicate the measurement results 0 hours after draining and 3a hours after draining when the immersion time is approximately 8a hours. The white triangles indicate the measurement results 0 hours after draining and 3a hours after draining when the immersion time is approximately 30a hours. The black circles indicate the measurement results 0 hours after draining and 3a hours after draining when the immersion time is approximately 50a hours. The black triangles indicate the measurement results 0 hours after draining and 3a hours after draining when the immersion time is approximately 180a hours. In Figure 8, four sets of changes in impurity content up to different time points are shown.

[0074] As shown in Figure 8, the slope of the dotted line connecting measurement results from the same set decreases as the immersion time increases. In other words, the change in impurity content decreases as the immersion time increases.

[0075] Figure 9 is a plot of the slopes of the dotted lines shown in Figure 8. In Figure 9, the vertical axis represents the slope (relative value) of the dotted lines in Figure 8, and the horizontal axis represents the immersion time [h].

[0076] Plotting the slopes of the four dotted lines shown in Figure 8 results in the arrangement shown in Figure 9, and an approximate straight line 300 can be shown for these plots. Note that the approximate line showing the relationship between plots is not limited to a straight line; for example, it may be an approximate curve obtained by fitting or other methods.

[0077] As shown in Figure 9, the value of the corresponding slope of the approximation line 300 decreases over time. In other words, the change in the impurity content in the cleaning solution slows down over time. If we set a threshold slope (a slope of 1 in Figure 9) where the change in the impurity content in the cleaning solution is considered to be almost negligible, the point in time when the approximation line 300 falls below this threshold can be considered the appropriate cleaning time for the measurement line 28A. That is, the appropriate cleaning time for the measurement line 28A can be calculated based on the time progression of the change in impurity content.

[0078] Furthermore, the detection of impurity content in the cleaning solution is repeated until the above plot shows a suitable approximation line 300 (i.e., until a sufficient number of plots are available to calculate the cleaning time with the required accuracy). In other words, once the cleaning time has been calculated with sufficient accuracy, detection of impurity content in the cleaning solution is no longer necessary. This prevents excessive dispensing of the cleaning solution and the detection of impurity content in the cleaning solution.

[0079] According to the method described above, an approximate straight line 300 can be calculated based on the time change in the impurity content of the cleaning solution at multiple points in time. Furthermore, by calculating the point in time when the value of the approximate straight line 300 falls below a threshold, the cleaning time of the measurement line 28A can be estimated. Therefore, even in the case of resin components, where impurities introduced during the manufacturing process are released, it becomes unnecessary to set an excessively long cleaning time, thereby increasing the efficiency of substrate processing.

[0080] Furthermore, since the cleaning time for the measurement line 28A can be estimated, the substrate processing, including the cleaning time for the measurement line 28A, can be automatically executed to improve work efficiency.

[0081] For example, first, the location in the entire substrate processing apparatus 1 where parts replacement or other operations are performed is identified as the measurement line 28A. Then, under the control of the control unit 90, cleaning solution is supplied from the processing solution supply source 29 to the measurement line 28A.

[0082] Next, the control unit 90 controls the discharge of cleaning solution from the measurement line 28A at timings corresponding to different immersion times, and the particle detector 702 measures the impurity content in the discharged cleaning solution. The information of the impurity content in the cleaning solution output from the particle detector 702 and the corresponding immersion time obtained from control information such as valves is then input to the control unit 90.

[0083] The control unit 90 calculates the time change in the impurity content at multiple points in time based on the input information of the impurity content and the corresponding immersion time. Then, the control unit 90 creates a graph as shown in Figure 9 and calculates the time at which the approximation line falls below a predetermined threshold, i.e., the cleaning time of the measurement line 28A.

[0084] The control unit 90 then determines whether the calculated cleaning time is longer than the cumulative time the measurement line 28A has been immersed in the cleaning solution at that time. If the calculated cleaning time is longer than the cumulative time the measurement line 28A has been immersed, the control unit 90 continues immersing the measurement line 28A until the calculated cleaning time is reached. On the other hand, if the calculated cleaning time is shorter than the cumulative time the measurement line 28A has been immersed, the control unit 90 terminates the immersion of the measurement line 28A and automatically moves on to substrate processing.

[0085] <Regarding the detection of impurities> In the above example, particles were detected by the particle detector 702 from the cleaning solution discharged onto the substrate W, but particles may also be detected within the measurement line 28A.

[0086] Figure 10 is a schematic side view showing an example of the processing unit 600A and its related configuration according to this embodiment. The configuration shown in Figure 10 is the same as the configuration in Figure 3, except that the particle detector 702 in Figure 3 is replaced with a particle counter 704.

[0087] As shown in Figure 10, the particle counter 704 is an optical particle measuring instrument connected to the measurement line 28A. The particle counter 704 samples the cleaning solution in the measurement line 28A and detects the particles present in the sampled cleaning solution based on the response wavelength obtained from the measurement of the cleaning solution.

[0088] With this configuration, the impurity content can be continuously detected within the measurement line 28A without discharging the cleaning solution from the processing solution nozzle 20. In this case, the measurement line 28A can be immersed continuously, and the start time of immersion is set to be the same as the set immersion time, so that the corresponding impurity content is detected each time the set immersion time is reached.

[0089] Furthermore, when some components of the substrate processing apparatus 1 are replaced, the cleaning time for the newly replaced components can be calculated based on the cleaning time already calculated for similar components that have been replaced in the past. In this way, the impurity content can be measured at an effective timing for calculating the cleaning time. As a result, the number of measurements required to calculate the cleaning time can be reduced.

[0090] <Regarding the effects produced by the embodiments described above> Next, examples of the effects produced by the embodiments described above will be shown. In the following description, the effects will be described based on the specific configurations illustrated in the embodiments described above, but they may be replaced with other specific configurations illustrated in this specification to the extent that similar effects are produced. That is, for convenience, in the following, only one of the corresponding specific configurations may be described as representative, but the specific configuration described as representative may be replaced with another corresponding specific configuration.

[0091] According to the embodiment described above, in the cleaning time calculation method, the piping line for supplying the processing liquid to the processing unit 600 that processes the substrate W is filled with cleaning liquid. Then, a first content change (for example, the time change of content connecting the white circles in Figure 8), which is the time change of the impurity content in the cleaning liquid that occurred in the piping line up to a first time, and a second content change (for example, the time change of content connecting the black circles in Figure 8), which is the time change of the impurity content in the cleaning liquid that occurred in the piping line up to a second time, which is a time after the first time, are measured. Then, the cleaning time for the piping line is calculated based on the difference between the first content change and the second content change (for example, the time transition of the content change decreasing from the white circle plot to the black circle plot in Figure 9).

[0092] With this configuration, the appropriate cleaning time for the measurement line 28A can be calculated based on the time course of the change in impurity content.

[0093] Furthermore, the same effect can be achieved even if other configurations exemplified in this specification are added to the above configuration as appropriate, that is, if other configurations in this specification that were not mentioned as the above configuration are added as appropriate.

[0094] Furthermore, according to the embodiments described above, the step of filling the piping line with cleaning solution is performed after draining the cleaning solution that had already filled the piping line (i.e., draining at the timing of flushing which serves as the basis for the immersion time, or when switching immersion times), and then filling the piping line with cleaning solution. With such a configuration, it becomes easier to manage each immersion time.

[0095] Furthermore, according to the embodiments described above, the first content change and the second content change are changes in the particle content contained in the cleaning solution. With this configuration, an appropriate cleaning time for the measurement line 28A can be calculated based on the time progression of the particle content change.

[0096] Furthermore, according to the embodiments described above, the cleaning solution is a chemical solution for treating the substrate W. With this configuration, the chemical solution used for treating the substrate can also be used for immersion in the piping line.

[0097] Furthermore, according to the embodiments described above, the cleaning solution is isopropyl alcohol. With this configuration, even when drying is performed as a pretreatment for detecting the impurity content, it is possible to detect the impurity content while suppressing damage to the substrate W.

[0098] Furthermore, according to the embodiments described above, the steps of measuring the first content change and the second content change are repeated until the cleaning time is calculated. With this configuration, once the cleaning time has been calculated with sufficient accuracy, detection of impurity content in the cleaning solution becomes unnecessary, thus preventing excessive dispensing of the cleaning solution and detection of impurity content in the cleaning solution.

[0099] Furthermore, according to the embodiment described above, in the cleaning time calculation method, processing of the substrate W is started in the processing unit 600 after the calculated cleaning time has elapsed. With this configuration, the substrate processing can be automatically executed using the elapsed cleaning time of the calculated measurement line 28A as a trigger, thereby improving work efficiency.

[0100] Furthermore, according to the embodiments described above, the piping line includes a resin tube. With such a configuration, it is possible to set an appropriate cleaning time even in the face of the problem specific to resin components, such as the leakage of impurities that are mixed into the resin components during the manufacturing process.

[0101] Furthermore, according to the embodiment described above, the piping line includes a portion of the measurement line 28A, which is the target for calculating the cleaning time. The process for measuring the first and second content changes includes draining the cleaning liquid from the piping line located downstream of the measurement line 28A, discharging the cleaning liquid from the measurement line 28A onto the substrate W, drying the substrate W from which the cleaning liquid has been discharged, and detecting impurities on the dried substrate W. With this configuration, an appropriate cleaning time can be calculated for any point in the piping line. In addition, since impurities can be detected after drying the upper surface of the substrate W, impurities can be detected with higher accuracy than when cleaning liquid remains.

[0102] <Modifications of the embodiments described above> In the above embodiment, the measurement line 28A, which is part of the piping line, was used as the subject of the cleaning time calculation. However, the location of the measurement line 28A is not limited to the case shown in Figure 3, and the subject of the cleaning time calculation may be the entire piping line through which a certain treatment liquid flows. When calculating the cleaning time for the entire piping line, it is not necessary to drain the cleaning liquid downstream of the measurement line 28A in advance.

[0103] Furthermore, in the above embodiment, immersion was performed by the cleaning solution remaining in the measurement line 28A, but it is sufficient for the resin member inside the measurement line 28A to be in contact with the cleaning solution, and for example, immersion may occur by the cleaning solution flowing through the measurement line 28A.

[0104] Furthermore, in the above embodiments, the material, dimensions, shape, relative arrangement, or implementation conditions of each component may also be described, but these are merely examples and not limiting in all aspects.

[0105] Therefore, countless variations and equivalents not shown are envisioned within the scope of the art disclosed in this specification. For example, these include modifications, additions, or omissions of at least one component.

[0106] Furthermore, in at least one embodiment described above, if a material name or the like is mentioned without further specification, it is assumed that the material includes other additives, such as an alloy, unless otherwise specified, to avoid any inconsistencies. [Explanation of Symbols]

[0107] 28 Piping 28A Measurement Line 103 Impurities 103A Impurities 103B Impurities 120 Treatment solution 120A cleaning solution 600 processing units 600A Processing Unit W board

Claims

1. The process involves filling the piping line for supplying the processing liquid to the processing unit that processes the circuit board with cleaning liquid, A step of measuring a first content change, which is the time change in the impurity content of the cleaning solution that occurred in the piping line up to a first time, and a second content change, which is the time change in the impurity content of the cleaning solution that occurred in the piping line up to a second time, which is a time later than the first time. The process includes a step of calculating the cleaning time for the piping line until the time progression of the content change, calculated based on the first content change and the second content change, falls below a predetermined threshold, Method for calculating washing time.

2. The method for calculating the washing time according to claim 1, The step of filling the piping line with the cleaning solution is the step of draining the cleaning solution that was already filling the piping line and then filling the piping line with the cleaning solution. Method for calculating washing time.

3. A method for calculating washing time according to claim 1 or 2, The first content change and the second content change are changes in the particle content contained in the cleaning solution. Method for calculating washing time.

4. A method for calculating washing time according to claim 1 or 2, The cleaning solution is a chemical solution for treating the substrate. Method for calculating washing time.

5. A method for calculating washing time according to claim 1 or 2, The aforementioned cleaning solution is isopropyl alcohol. Method for calculating washing time.

6. A method for calculating washing time according to claim 1 or 2, The process of measuring the first content change and the second content change is repeated until the washing time is calculated. Method for calculating washing time.

7. A method for calculating washing time according to claim 1 or 2, The process further includes a step of starting the processing of the substrate in the processing unit after the calculated cleaning time has elapsed. Method for calculating washing time.

8. A method for calculating washing time according to claim 1 or 2, The aforementioned piping line includes a resin tube, Method for calculating washing time.

9. A method for calculating washing time according to claim 1 or 2, The aforementioned piping line includes in part the measurement line which is the target for calculating the cleaning time, The steps for measuring the first content change and the second content change are as follows: The process involves draining the cleaning liquid from the piping line located downstream of the measurement line, and then discharging the cleaning liquid from the measurement line onto the substrate. A step of drying the substrate from which the cleaning solution has been discharged, The process includes a step of detecting impurities on the dried substrate. Method for calculating washing time.

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