Substrate processing apparatus, and substrate processing method

Abstract

The present invention provides a substrate processing apparatus capable of detecting component degradation with high precision. The substrate processing apparatus (100) includes: a substrate holding section (20) having a conductive material layer (22) and a protective layer (23) laminated on the surface of a substrate member (21) in a portion to be immersed in a processing liquid (L); and a control section (40) that detects the occurrence of an abnormality in the substrate holding section (20) based on at least one of a current value and a resistance value generated in the case of a potential difference between the conductive material layer (22) and the processing liquid (L).

Description

Technical Field

[0001] This invention relates to a substrate processing apparatus and a substrate processing method. Prior Technology

[0002] Patent Document 1 discloses an example of a substrate processing apparatus in which a processing liquid is stored in a processing tank, and a substrate is immersed in the processing tank using a lifter for holding the substrate and then cleaned. This substrate processing apparatus includes an inspection unit for inspecting the deterioration of metallic components constituting the lifter and coated with resin. The inspection unit comprises a measurement unit for measuring a predetermined metal concentration in the liquid contacting the component being inspected; and a deterioration determination unit for determining the degree of deterioration of the component being inspected by comparing the metal concentration measured by the measurement unit with a predetermined threshold value. [Previous Technical Documents] [Patent Literature]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-029471. Summary of the Invention

[0004] [The problem that the invention aims to solve] However, the inspection unit of the substrate processing apparatus disclosed in Patent Document 1 cannot determine whether the metal in the processing liquid has already adhered to the wafer during pretreatment, or whether the metal in the processing liquid originates from the deterioration of the object being inspected. Therefore, there is a problem with the high-precision detection of component deterioration using this inspection unit.

[0005] One aspect of the present invention is to realize a substrate processing apparatus capable of detecting component deterioration with high precision.

[0006] [Methods used to solve problems] To address the issues described above, one embodiment of the present invention is a substrate processing apparatus for immersing a substrate in a processing liquid and performing surface treatment, comprising: a processing tank for storing the processing liquid; a substrate holding section for holding the substrate at a predetermined position in the processing liquid within the processing tank, wherein at least in the portion to be immersed in the processing liquid, a conductive material layer and a protective layer are sequentially laminated on the surface of a base member from the side of the base member; a measuring section for measuring, during the surface treatment, at least one of the following two conditions in which a potential difference is generated between the conductive material layer and the processing liquid in which the substrate is immersed in the processing tank: a current value flowing between the conductive material layer and the processing liquid; and a resistance value between the conductive material layer and the processing liquid; and a control section for detecting the occurrence of an abnormality in the substrate holding section based on at least one of the aforementioned current value and the aforementioned resistance value.

[0007] Furthermore, one embodiment of the present invention is a substrate processing method for immersing a substrate in a processing liquid and performing surface treatment in a substrate processing apparatus. The substrate processing apparatus includes: a processing tank for storing the processing liquid; a substrate holding section for holding the substrate at a predetermined position in the processing liquid within the processing tank, wherein at least in the portion to be immersed in the processing liquid, a conductive material layer and a protective layer are sequentially laminated on the surface of a substrate member from the side of the substrate member; and a measuring section for measuring, during the surface treatment, at least one of the following two conditions in which a potential difference is generated between the conductive material layer and the processing liquid in which the substrate is immersed in the processing tank: the current value flowing between the conductive material layer and the processing liquid; and the current value of the conductive material layer. The resistance value between the material layer and the aforementioned processing liquid; the aforementioned substrate processing method includes the following steps: storing the aforementioned processing liquid in the aforementioned processing tank; and holding the aforementioned substrate at a predetermined position in the aforementioned processing liquid by the aforementioned substrate holding part; the aforementioned substrate processing method further includes the following steps: in parallel with the step of holding the aforementioned substrate in the aforementioned processing liquid, measuring at least one of the current value flowing between the aforementioned conductive material layer and the aforementioned processing liquid and the resistance value between the aforementioned conductive material layer and the aforementioned processing liquid in the case where a potential difference is generated between the aforementioned conductive material layer and the aforementioned processing liquid in the aforementioned processing tank where the aforementioned substrate is immersed, and detecting the occurrence of an abnormality in the aforementioned substrate holding part based on the aforementioned current value and the aforementioned resistance value.

[0008] [Invention Benefits] According to one embodiment of the present invention, a substrate processing apparatus or the like can be realized that can detect the deterioration of components with high precision. Simple Explanation of the Diagram

[0009] [Figure 1] is a schematic cross-sectional view of the overall structure of the substrate processing apparatus in Embodiment 1. [Figure 2] is a cross-sectional view showing the main components of the substrate processing apparatus in Embodiment 1. [Figure 3] is a top view illustrating the structure of the substrate holding part. [Figure 4] is a block diagram illustrating the structure of the main parts of a substrate processing device. [Figure 5] is a cross-sectional view illustrating the specific structure of the substrate holding section and the measuring section. [Figure 6] is a flowchart illustrating a substrate processing method performed by a substrate processing apparatus. [Figure 7] is a diagram showing the configuration of the main parts of the substrate processing apparatus in Embodiment 2. [Figure 8] is a diagram showing the configuration of the main parts of the substrate processing apparatus in Embodiment 3. Implementation

[0010] [Implementation Mode 1] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

[0011] Figure 1 is a schematic cross-sectional view showing the overall structure of the substrate processing apparatus 100 according to Embodiment 1 of the present invention. Figure 2 is a cross-sectional view showing the structure of the main parts of the substrate processing apparatus 100. Figure 3 is a top view showing the structure of the substrate holding section 20. Figure 4 is a block diagram showing the structure of the main parts of the substrate processing apparatus 100. Figure 5 is a cross-sectional view showing the specific structure of the substrate holding section 20 and the measuring section 30.

[0012] The substrate processing apparatus 100 immerses a substrate W in a processing solution L and performs surface treatment. The processing solution L is omitted in FIG1. ​​The substrate W is, for example, a semiconductor wafer. As shown in FIGS. 1 to 4, the substrate processing apparatus 100 includes a processing tank 10, a substrate holding section 20, a measuring section 30, and a control section 40.

[0013] The processing tank 10 is for storing the processing solution L. The processing tank 10 has a shape that allows the entire substrate W to be immersed in the stored processing solution L. The processing tank 10 may also be formed of a material that is resistant to corrosion of the processing solution L.

[0014] The substrate processing apparatus 100 further includes a processing liquid supply source 13, an ejector pipe 15, an overflow tank 17, and a discharge liquid recovery unit 19. The processing liquid supply source 13 supplies processing liquid L to the ejector pipe 15. The ejector pipe 15 is disposed at the bottom of the processing tank 10 and supplies the processing liquid L supplied from the processing liquid supply source 13 into the processing tank 10. The ejector pipe 15 can also be a so-called upflow pipe, used to spray the processing liquid upwards towards the processing tank 10. Furthermore, the ejector pipe 15 can also spray the processing liquid along the bottom surface of the processing tank 10. The overflow tank 17 stores the processing liquid L overflowing from the processing tank 10. The discharge liquid recovery unit 19 recovers the processing liquid L stored in the overflow tank 17.

[0015] For clarity, Figure 1 shows the nozzle 15 detached from the treatment tank 10. However, as shown in Figure 2, the nozzle 15 can also be embedded in a portion of the treatment tank 10. Furthermore, the treatment fluid supply source 13 and the discharge fluid recovery unit 19 are omitted in figures other than Figure 1.

[0016] The processing tank 10 can also be a so-called CHB (Chemical Bath) tank, used to circulate a single type of processing solution L and process the substrate W. In this case, the substrate processing apparatus 100 further includes: piping and a pump for circulating the processing solution L; a heater for heating the processing solution L; and a filter for filtering the processing solution L. Alternatively, the processing tank 10 can also be a so-called ONB (One Bath) tank, used to continuously replace the chemical solution and pure water as the processing solution L for surface treatment.

[0017] The substrate holding unit 20 holds the substrate W at a predetermined position in the processing liquid L within the processing tank 10. The predetermined position is the position where the substrate W is entirely immersed in the processing liquid L. Specifically, the substrate holding unit 20 is a lifter that allows the substrate W to move at least between the predetermined position and a position above that predetermined position. More specifically, the substrate holding unit 20 moves the substrate W to a position above the predetermined position where the substrate W is entirely removed from the processing liquid L. In the following description, the predetermined position will be referred to as the immersion position, and the position where the substrate W is entirely removed from the processing liquid L will be referred to as the retrieval position.

[0018] The substrate holding section 20 moves the substrate W from the retrieval position to the immersion position, thereby immersing the substrate W in the processing liquid L. Furthermore, the substrate holding section 20 moves the substrate W from the immersion position to the retrieval position, thereby retrieving the substrate W from the processing liquid L.

[0019] The substrate holding portion 20 may also include: a mounting portion 26 for mounting a plurality of substrates W; and a back plate 27 disposed at one end of the mounting portion 26 and extending vertically along the sidewall of the processing tank 10. The mounting portion 26 may also have any shape capable of mounting a plurality of substrates W. Thus, the substrate holding portion 20 can hold a plurality of substrates W and move the substrates W between a retrieval position and an immersion position. The substrate holding portion 20 further includes: a drive mechanism 28 for raising and lowering the mounting portion 26 and the back plate 27.

[0020] In the example shown in Figure 3, the mounting portion 26 consists of three rod-shaped components that extend parallel to the direction in which the substrates W are arranged. The mounting portion 26 supports the ends of the substrates W at three points. Furthermore, the mounting portion 26 is provided with comb teeth K, which have a plurality of grooves arranged at predetermined intervals along its length. These grooves are used to allow the outer edges of the substrates W to be inserted and to hold the substrates W in an upright position. In this way, the substrate holding portion 20 can hold the substrates W in a stable state.

[0021] As shown in Figures 2 and 5, the substrate holding portion 20 has the following structure: at least in the portion to be immersed in the processing liquid L, a conductive material layer 22 and a protective layer 23 are sequentially laminated on the surface of the substrate member 21 from the side of the substrate member 21. The substrate member 21 may also be formed of a material with strength sufficient to withstand the weight of the substrate W. The conductive material layer 22 may also be formed of a material that is conductive and has minimal impact on the processing liquid L even if dissolved. The protective layer 23 may also be formed of a material that has even lower conductivity than the conductive material layer 22 and is corrosion resistant to the processing liquid L.

[0022] For example, the substrate member 21 is made of quartz material, and the protective layer 23 is made of PFA (Perfluoroalkoxy alkanes) or PCTFE (Polychlorotrifluoroethylene). This gives the substrate holding portion 20 the strength to withstand the weight of the substrate W. Furthermore, the protective layer 23 protects the substrate member 21 from the effects of processing solutions such as hydrofluoric acid.

[0023] The materials constituting the base member 21 and the protective layer 23 are not limited to the examples described above. For example, the base member 21 may also be made of a material different from quartz, such as PEEK (Polyetheretherketone). Furthermore, carbon can be cited as an example of the material used for the conductive material layer 22, but it is not a limitation.

[0024] The measurement unit 30 measures at least one of the following in the case where a potential difference is generated between the conductive material layer 22 and the processing liquid L in which the substrate W is immersed in the processing tank 10 during surface treatment: (1) the current value flowing between the conductive material layer 22 and the processing liquid L; and (2) the resistance value between the conductive material layer 22 and the processing liquid L.

[0025] The control unit 40 controls various parts of the substrate processing apparatus 100, thereby controlling the operation of the substrate processing apparatus 100. The control unit 40 includes one or more processors or circuits. The processors or circuits may include a central processing unit (CPU), a microprocessor unit (MPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), or a field-programmable gate array (FPGA), but are not limited to these. In Figure 1, the control unit 40 includes a CPU 41.

[0026] Furthermore, the control unit 40 may also include memory 42 as a memory medium. Memory medium can also be called non-transitory computer readable medium. Memory medium may also include hard disk or random access memory (RAM), but is not limited to these.

[0027] As shown in Figure 4, the control unit 40 controls the operation of the substrate holding unit 20. In addition, the control unit 40 detects the occurrence of abnormalities in the substrate holding unit 20 based on at least one of the current value measured by the measuring unit 30 and the measured value.

[0028] The "abnormality" of the substrate holding portion 20 referred to in this specification means that the conductive material layer 22 is exposed to the processing liquid L due to the deterioration of the protective layer 23. In other words, at the point in time when the abnormality occurred, the substrate member 21 was not exposed to the processing liquid L. Therefore, there is a leeway in time between the occurrence of the abnormality and the corrosion of the substrate member 21 by the processing liquid L.

[0029] As explained above, the conductive material layer 22 is formed of a conductive material. Furthermore, the protective layer 23 is formed of a material with lower conductivity than the conductive material layer 22. Therefore, in the case where the conductive material layer 22 is exposed to the processing liquid L due to deterioration of the protective layer 23, the current flowing between the conductive material layer 22 and the processing liquid L increases, and the resistance between the conductive material layer 22 and the processing liquid L decreases. Therefore, the control unit 40 can detect the occurrence of abnormalities in the substrate holding section 20 with high precision during the surface treatment of the substrate W.

[0030] For example, the control unit 40 detects an abnormality in the substrate holding section 20 in at least one of the following situations: the current value measured by the measuring unit 30 exceeds a predetermined threshold value, or the resistance value measured by the measuring unit 30 is lower than a predetermined threshold value. The predetermined threshold value for the current value can also be an upper limit value of the current value measured by the measuring unit 30 that is assumed to occur in the substrate holding section 20 without any abnormality. Similarly, the predetermined threshold value for the resistance value can also be a lower limit value of the resistance value measured by the measuring unit 30 that is assumed to occur in the substrate holding section 20 without any abnormality. In this way, the control unit 40 can easily detect the occurrence of an abnormality in the substrate holding section 20 during the surface treatment of the substrate W based on the current value measured by the measuring unit 30 and at least one of the measured values.

[0031] As shown in Figure 5, the measuring unit 30 includes: a wiring 31 having a terminal 31a, the terminal 31a being connected to a contact portion 22a in the conductive material layer 22; and an electrode 32 disposed in the processing liquid L within the processing tank 10. The contact portion 22a and the terminal 31a are disposed in a position not in contact with the processing liquid L when the substrate holding portion 20 holds the substrate W in the immersion position. The terminal 31a, wiring 31, and electrode 32 are not particularly limited, and known materials such as metals can be used.

[0032] Furthermore, the measuring unit 30 includes a measuring device 33. The measuring device 33 is at least one of an ammeter and a resistance meter; the ammeter measures the current flowing between the contact portion 22a and the electrode 32; the resistance meter measures the resistance between the contact portion 22a and the electrode 32. Therefore, the control unit 40 can detect abnormalities in the substrate holding portion 20 based on the current or resistance value measured by the measuring device 33. There are no particular limitations on the ammeter and / or resistance meter used as the measuring device 33; any known measuring device can be used.

[0033] The control unit 40 can also output a warning signal in at least one of the following situations: the current value measured by the measuring unit 30 exceeds a predetermined threshold, or the resistance value measured by the measuring unit 30 falls below a predetermined threshold. Therefore, the control unit 40 can output a warning signal when an abnormality occurs in the substrate holding unit 20. The warning signal can also be input to a monitor displaying warning messages, for example, for an administrator who manages the operation of the substrate processing apparatus 100. Furthermore, the warning signal can also be input to a warning device that outputs a warning to the administrator of the substrate processing apparatus 100 via an image or light. The administrator can be aware of an abnormality in the substrate holding unit 20 when a warning is output from a monitor or warning device.

[0034] Generally, the processing of substrate W is carried out according to a pre-determined production plan. In the substrate processing apparatus 100, the manager can be notified as early as possible when an abnormality occurs in the substrate holding section 20. Therefore, as explained above, the manager can take the following actions during the grace period until the substrate member 21 is corroded by the processing liquid L: replace the substrate holding section 20, or plan and carry out the recoating of the conductive material layer 22 onto the protective layer 23, thereby preventing the production plan from being hindered.

[0035] The substrate holding portion 20 may further include a contact portion protective layer 22b. The contact portion protective layer 22b protects the contact portion 22a. Specifically, the surface of the contact portion 22a other than the portion in contact with the terminal 31a is protected by the contact portion protective layer 22b. In this case, the contact portion protective layer 22b prevents deterioration of the contact portion 22a. That is, according to this configuration, materials other than carbon with low corrosion resistance to the processing liquid L can be used as the material for the conductive material layer 22, thereby expanding the range of material selection for the conductive material layer 22.

[0036] The following situation may occur: within the chamber of the substrate processing apparatus 100, the processing liquid L vaporizes and / or droplets of the processing liquid L disperse. In this situation, terminal 31a may be exposed to the gaseous environment of the vaporized or dispersed processing liquid L. Therefore, terminal 31a can also be configured to be corrosion-resistant. More specifically, terminal 31a can also be at least corrosion-resistant to the processing liquid L. This prevents corrosion of terminal 31a even when it is exposed to the gaseous environment of the vaporized or dispersed processing liquid L.

[0037] Specifically, the substrate processing apparatus 100 may further include a terminal sealing member 50, used to surround the terminal 31a with a predetermined gas when the terminal 31a is in contact with the contact portion 22a. The terminal sealing member 50 includes a covering member that covers at least a portion of the area surrounding the terminal 31a; and a gas supply mechanism that supplies the predetermined gas to the interior of the covering member. The predetermined gas is a type of gas that will not corrode the terminal 31a. Nitrogen (N2) is an example of a gas that will not corrode the terminal 31a, but it is not limited to this. In this way, the vapor of the processing liquid L is prevented from entering the interior of the covering member, thereby preventing corrosion of the terminal 31a.

[0038] The substrate processing apparatus 100 may not necessarily include the terminal sealing member 50. For example, the terminal 31a itself may be formed of a material resistant to corrosion of the processing liquid L. For example, the terminal 31a may also be made of carbon. Alternatively, the surface of the terminal 31a other than the portion in contact with the contact portion 22a may also be protected by a terminal protective layer. The terminal protective layer may also be formed of a material resistant to corrosion of the processing liquid L. With this configuration, corrosion of the terminal 31a can also be prevented.

[0039] Figure 6 is a flowchart illustrating a substrate processing method using the substrate processing apparatus 100. In the substrate processing method illustrated in Figure 6, the control unit 40 initially stores the processing liquid L in the processing tank 10 (step S1). Next, the control unit 40 holds the substrate W using the substrate holding unit 20 (step S2). In this state, the control unit 40 moves the substrate W from the retrieval position to the immersion position (step S3) and holds it in the immersion position (step S4). Thereby, the substrate W is surface-treated using the processing liquid L.

[0040] In parallel with step S4, the control unit 40 performs a process for detecting the occurrence of an abnormality in the substrate holding section 20. Specifically, the control unit 40 measures the resistance or current value between the conductive material layer 22 and the processing liquid L using the measuring unit 30 (step S5). Furthermore, the control unit 40 determines whether an abnormality has occurred in the substrate holding section 20 based on the measured resistance or current value (step S6).

[0041] If an abnormality is detected in the substrate holding section 20 (yes in step S6), the control unit 40 outputs an alarm signal (step S7). If no abnormality is detected in the substrate holding section 20 (no in step S6), the control unit 40 skips step S7.

[0042] Then, the control unit 40 determines whether the surface treatment of the substrate W by the processing liquid L has ended (step S8). The control unit 40 determines that the surface treatment has ended if, for example, the period during which the substrate W is held in the immersion position is a predetermined time or longer. In this case, the substrate processing apparatus 100 further includes a timer that measures the period during which the substrate W is held in the immersion position.

[0043] If the surface treatment of the substrate W has not yet been completed (no in step S8), the control unit 40 continues step S4 and repeats the process from step S5 in parallel. However, the control unit 40 may also repeat step S8 only if it determines that an abnormality has occurred in the substrate holding part 20 (yes in step S6).

[0044] When the surface treatment of substrate W has been completed (Yes in step S8), the control unit 40 moves substrate W from the immersion position to the retrieval position via substrate holding unit 20 (step S9). This concludes the substrate W processing method performed by substrate processing apparatus 100. Thus, as explained above, the occurrence of an abnormality in substrate holding unit 20 can be detected without stopping the processing of substrate W in the substrate processing method performed by substrate processing apparatus 100.

[0045] [Measurement Example] The inventors of this invention conducted the following experiment: While immersing the electrodes of the imitation substrate holding portion 20 and the electrode 32 in a processing solution, the resistance value between the electrodes was measured. The electrode of the imitation substrate holding portion 20 was an electrode with a carbon surface coated with a PCTFE film. The electrode of the imitation electrode 32 was an electrode made of glassy carbon. With their relative positions fixed using a fixture, these electrodes were immersed in hydrofluoric acid, which was the processing solution. The thickness of the PCTFE film in the electrodes of the imitation substrate holding portion 20 was varied, and the resistance value between these electrodes was measured.

[0046] The results of the resistance measurement are as follows. The resistance is infinite when the PCTFE film thickness is 350μm, 200μm and 100μm. When the PCTFE film thickness is 0 μm, the resistance is 0.032 MΩ.

[0047] As explained above, in the electrodes of the substrate holding section 20, the PCTFE film thickness becomes 0 μm, that is, it becomes a PCTFE film without a carbon-coated surface, thereby confirming the conductivity between the electrodes. Therefore, it can be anticipated that in the substrate processing apparatus 100, the measuring unit 30 measures the resistance value between the conductive material layer 22 and the processing liquid L, thereby also detecting the deterioration of the substrate holding section 20. Furthermore, it can be anticipated that even when the measuring unit 30 measures the current value between the conductive material layer 22 and the processing liquid L, the deterioration of the substrate holding section 20 can be detected in the same way.

[0048] [Implementation Mode Two] Figure 7 is a diagram showing the configuration of the main parts of the substrate processing apparatus 200 according to Embodiment 2. The shapes of some of the constituent elements are simplified in Figure 7. However, the actual shapes of these constituent elements are not particularly different from those of the constituent elements with the same element symbols in the substrate processing apparatus 100.

[0049] As shown in Figure 7, the difference between the substrate processing apparatus 200 and the substrate processing apparatus 100 is that the substrate processing apparatus 200 includes a measuring unit 30A instead of the measuring unit 30. The difference between the measuring unit 30A and the measuring unit 30A is that the measuring unit 30A includes an electrode 34 instead of the electrode 32, and a measuring instrument 35 instead of the measuring instrument 33. The measuring unit 30A measures the capacitance between the electrode 34 and the conductive material layer 22 during the surface treatment of the substrate W.

[0050] Electrode 34 is used to generate a potential difference between the conductive material layer 22 and the processing liquid. Electrode 34 has a structure in which an electrode protective layer 34b is laminated on the surface of the conductive material 34a. The conductive material 34a may also have the same structure as electrode 32 in the measuring unit 30. Electrode protective layer 34b is an insulating layer laminated on the surface of the conductive material 34a. Electrode protective layer 34b may also be formed of PFA or PCTEF, similar to the protective layer 23 in the substrate holding part 20.

[0051] Electrode 34 is immersed in the processing liquid during at least the measurement performed by the measuring unit 30A. For example, electrode 34 can also be raised and lowered in such a way that it is immersed in the processing liquid only during the measurement performed by the measuring unit 30A, and not immersed in the processing liquid during other periods. In the substrate processing apparatus 200, the conductive material 34a in electrode 34 does not directly contact the processing liquid, only the electrode protective layer 34b directly contacts the processing liquid.

[0052] The capacitance meter 35 is used to measure capacitance. In the substrate processing apparatus 200, the capacitance meter 35 measures the capacitance between the electrode 34 and the conductive material layer 22.

[0053] In the substrate processing apparatus 200, as the protective layer 23 and / or the electrode protective layer 34b deteriorate, the capacitance between the electrode 34 and the conductive material layer 22 increases. For example, the control unit 40 detects an abnormality in the substrate holding section 20 when the capacitance measured by the measuring unit 30A exceeds a predetermined threshold. The predetermined threshold for capacitance can also be conceived as the upper limit of the capacitance measured by the measuring unit 30A in the case where no abnormality occurs in the substrate holding section 20. In this way, the control unit 40 can easily detect the occurrence of an abnormality in the substrate holding section 20 based on the capacitance measured by the measuring unit 30A during the surface treatment of the substrate W.

[0054] [Measurement Example] The inventors of this invention conducted the following experiment: The capacitance between the electrodes of the imitation substrate holding portion 20 and the electrode 34 was measured while immersed in a processing solution. Electrodes with a carbon-coated surface using a PCTFE film were used as electrodes for both the imitation substrate holding portion 20 and the electrode 34. These electrodes were immersed in hydrofluoric acid, which served as the processing solution, while their relative positions were fixed using a fixture. The PCTFE film thickness in the imitation electrode 34 was fixed at 350 μm, and the capacitance between these electrodes was measured by varying the PCTFE film thickness in the electrode of the imitation substrate holding portion 20.

[0055] The capacitance measurement results are as follows. In the following measurement results, the capacitance rating is 1% ≒ 2pF. In the case of a PCTFE film thickness of 350 μm, the capacitance rating is 18%. In the case of a PCTFE film thickness of 200 μm, the capacitance rating is 23.8%. In the case of a PCTFE film thickness of 100 μm, the capacitance rating is 31%.

[0056] As explained above, it was confirmed in the electrodes of the substrate holding section 20 that the capacitance increases as the PCTFE film thickness decreases. Therefore, it can be anticipated that in the substrate processing apparatus 200, the measuring unit 30A measures the capacitance between the conductive material layer 22 and the electrode 34, thereby also detecting the deterioration of the substrate holding section 20.

[0057] [Implementation Mode Three] Figure 8 is a diagram showing the configuration of the main parts of the substrate processing apparatus 300 according to Embodiment 3. Similar to Figure 7, the shapes of some components are simplified in Figure 8. As shown in Figure 8, the difference from the substrate processing apparatus 100 is that the substrate processing apparatus 300 includes a measuring unit 60 instead of the measuring unit 30. The measuring unit 60 includes a first protection electrode 61, a second protection electrode 62, and a measuring instrument 35. The measuring unit 60 measures the capacitance between the first protection electrode 61 and the second protection electrode 62 during the surface treatment of the substrate W.

[0058] The first protective electrode 61 has a structure in which an electrode protective layer 61b is laminated on the surface of the conductive material 61a. The second protective electrode 62 has a structure in which an electrode protective layer 62b is laminated on the surface of the conductive material 62a. The conductive materials 61a and 62a may also be the same as the conductive material 34a in the electrode 34. The thickness and composition of the electrode protective layers 61b and 62b may also be the same as the thickness and composition of the protective layer 23 in the substrate holding portion 20.

[0059] The first protective electrode 61 and the second protective electrode 62 are immersed in the processing liquid for the same period as the period during which the substrate holding portion 20 is immersed in the processing liquid in the processing tank 10. Specifically, the first protective electrode 61 and the second protective electrode 62 can also be raised and lowered in conjunction with the raising and lowering of the substrate holding portion 20, thereby switching between the state of being immersed in the processing liquid and the state of not being immersed in the processing liquid. In the substrate processing apparatus 300 under normal conditions, the conductive materials 61a and 62a in the first protective electrode 61 and the second protective electrode 62 are not in direct contact with the processing liquid, but the electrode protective layers 61b and 62b are in direct contact with the processing liquid.

[0060] In the substrate processing apparatus 300, the measuring device 35 measures the capacitance between the first protective electrode 61 and the second protective electrode 62. In the substrate processing apparatus 300, as the electrode protective layers 61b and 62b deteriorate, the capacitance between the first protective electrode 61 and the second protective electrode 62 decreases.

[0061] As explained above, the materials and thicknesses of the electrode protective layers 61b and 62b are the same as those of the protective layer 23 in the substrate holding portion 20. Furthermore, the immersion time of the electrode protective layers 61b and 62b in the processing solution is approximately the same as the immersion time of the protective layer 23 in the processing solution. Therefore, it is assumed that the degree of degradation of the protective layer 23 in the substrate processing apparatus 300 at a certain point in time is approximately the same as the degree of degradation of the electrode protective layers 61b and 62b at the same point in time.

[0062] For example, the control unit 40 detects an abnormality in the substrate holding section 20 when the capacitance measured by the measurement unit 60 is lower than a predetermined threshold value. The predetermined threshold value for capacitance can also be a lower limit value of the capacitance measured by the measurement unit 60 that is assumed to occur when no abnormality occurs in the substrate holding section 20. In this way, the control unit 40 can easily detect an abnormality in the substrate holding section 20 based on the capacitance measured by the measurement unit 60 during the surface treatment of the substrate W. In particular, since the measurement unit 60 detects the abnormality based on the capacitance between the first protection electrode 61 and the second protection electrode 62, it can detect an abnormality in the substrate holding section 20 where the conductive material layer 22 does not have a contact portion 22a. Therefore, the measurement unit 60 can be easily applied to existing substrate processing apparatuses.

[0063] [Measurement Example] The inventors of this invention conducted the following experiment: While immersing electrodes simulating the first protective electrode 61 and the second protective electrode 62 in a treatment solution, the capacitance between these electrodes was measured. Electrodes simulating the first protective electrode 61 and the second protective electrode 62 were electrodes with a carbon surface coated with a PCTFE film. With their relative positions fixed using a fixture, these electrodes were immersed in hydrofluoric acid, which served as the treatment solution. The capacitance between these electrodes was measured while maintaining a uniform thickness of the PCTFE film in each electrode simulating the first protective electrode 61 and the second protective electrode 62.

[0064] The capacitance measurement results are as follows. Similar to the measurement example in Embodiment Two, the capacitance rating in the following measurement results is 1% ≒ 2pF. In the case of a PCTFE film thickness of 350 μm, the capacitance rating is 18%. In the case of a PCTFE film thickness of 200 μm, the capacitance rating is 42.1%. In the case of a PCTFE film thickness of 100 μm, the capacitance rating is 73.3%.

[0065] As explained above, it was confirmed in the electrodes that mimic the first protection electrode 61 and the second protection electrode 62 that the capacitance increases as the PCTFE film thickness decreases. Therefore, it can be foreseen that in the substrate processing apparatus 300, the measuring unit 60 measures the capacitance between the first protection electrode 61 and the second protection electrode 62, thereby also detecting the deterioration of the substrate holding unit 20.

[0066] [Compilation] One embodiment of the present invention is a substrate processing apparatus for immersing a substrate in a processing liquid and performing surface treatment, comprising: a processing tank for storing the processing liquid; a substrate holding section for holding the substrate at a predetermined position in the processing liquid within the processing tank, wherein at least in the portion to be immersed in the processing liquid, a conductive material layer and a protective layer are sequentially laminated on the surface of a substrate member from the side of the substrate member; a measuring section for measuring at least one of the following in the case where a potential difference is generated between the conductive material layer and the processing liquid in which the substrate is immersed in the processing tank during the surface treatment: a current value flowing between the conductive material layer and the processing liquid; and a resistance value between the conductive material layer and the processing liquid; and a control section for detecting the occurrence of an abnormality in the substrate holding section based on at least one of the aforementioned current value and the aforementioned resistance value.

[0067] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, the aforementioned measuring unit includes: wiring having terminals connected to contacts in the aforementioned conductive material layer; and electrodes disposed in the aforementioned processing liquid within the aforementioned processing tank; the aforementioned measuring unit includes at least one of an ammeter and a resistance meter; the ammeter measures the current flowing between the aforementioned contacts and the aforementioned electrodes; and the resistance meter measures the resistance between the aforementioned contacts and the aforementioned electrodes.

[0068] Furthermore, in one of the substrate processing apparatuses of the present invention, the aforementioned contact portion is protected by the aforementioned protective layer.

[0069] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, the aforementioned terminals are corrosion resistant.

[0070] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, a terminal sealing member is further provided, which is used to surround the terminal with a predetermined gas when the terminal is in contact with the contact portion.

[0071] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, the aforementioned terminals are formed of carbon.

[0072] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, the surface of the aforementioned terminal other than the portion that contacts the aforementioned contact portion is protected by a terminal protective layer.

[0073] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, the aforementioned control unit outputs a warning signal in at least one of the cases where the aforementioned current value exceeds a predetermined threshold value and the aforementioned resistance value is lower than a predetermined threshold value.

[0074] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, the aforementioned substrate holding portion includes: a mounting portion for mounting a plurality of the aforementioned substrates; and a back plate disposed at one end of the aforementioned mounting portion and extending vertically along the sidewall of the aforementioned processing groove.

[0075] Furthermore, in one embodiment of the substrate processing apparatus of the present invention, the aforementioned substrate member is made of quartz material; the aforementioned protective layer is made of PFA or PCTEF.

[0076] Furthermore, one embodiment of the present invention is a substrate processing method for immersing a substrate in a processing liquid and performing surface treatment in a substrate processing apparatus. The substrate processing apparatus includes: a processing tank for storing the processing liquid; a substrate holding section for holding the substrate at a predetermined position in the processing liquid within the processing tank, and having a conductive material layer and a protective layer sequentially laminated on the surface of a substrate member from the side of the substrate member, at least in the portion to be immersed in the processing liquid; and a measuring section for measuring at least one of the following during the surface treatment when a potential difference is generated between the conductive material layer and the processing liquid in which the substrate is immersed in the processing tank: the current value flowing between the conductive material layer and the processing liquid; and the current value of the conductive material layer. The resistance value between the layer and the aforementioned processing liquid; the aforementioned substrate processing method includes the following steps: storing the aforementioned processing liquid in the aforementioned processing tank; and holding the aforementioned substrate at a predetermined position in the aforementioned processing liquid by the aforementioned substrate holding portion; the aforementioned substrate processing method further includes the following steps: in parallel with the step of holding the aforementioned substrate in the aforementioned processing liquid, measuring at least one of the current value flowing between the aforementioned conductive material layer and the aforementioned processing liquid and the resistance value between the aforementioned conductive material layer and the aforementioned processing liquid in the case where a potential difference is generated between the aforementioned conductive material layer and the aforementioned processing liquid in the aforementioned processing tank where the aforementioned substrate is immersed, and detecting the occurrence of an abnormality in the aforementioned substrate holding portion based on at least one of the aforementioned current value and the aforementioned resistance value.

[0077] 10: Processing tank 13: Processing fluid supply source 15: Ejector Pipe 17: Overflow channel 19: Effluent Recovery Section 20: Substrate holding section 21: Base Components 22: Conductive material layer 22a: Contact part 22b: Contact part protective layer 23: Protective layer 26: Loading section 27: Back panel 28: Drive mechanism 30, 30A, 60: Measurement Department 31: Wiring 31a:Terminal 32, 34: Electrodes 33, 35: Measuring instruments 34a, 61a, 62a: Conductive materials 34b, 61b, 62b: Electrode protective layer 40: Control Department 41: CPU 42: Memory 50: Terminal sealing component 61: First protective electrode 62: Second protective electrode 100, 200, 300: Substrate processing apparatus K: Comb teeth L: Treatment fluid S1 to S9: Steps W: substrate

Claims

1. A substrate processing apparatus for immersing a substrate in a processing liquid and performing surface treatment, comprising: a processing tank for storing the processing liquid; a substrate holding section for holding the substrate at a predetermined position in the processing liquid within the processing tank, wherein at least in the portion to be immersed in the processing liquid, a conductive material layer and a protective layer are sequentially laminated on the surface of a substrate member from the side of the substrate member; a measuring section for measuring at least one of the following three in the case where a potential difference is generated between the conductive material layer and the processing liquid in which the substrate is immersed in the processing tank during the surface treatment: a current value flowing between the conductive material layer and the processing liquid; a resistance value between the conductive material layer and the processing liquid; and a capacitance between an electrode disposed in the processing liquid within the processing tank and the conductive material layer; and a control section for detecting the occurrence of an abnormality in the substrate holding section based on at least one of the aforementioned current value, the aforementioned resistance value, and the aforementioned capacitance.

2. The substrate processing apparatus as described in claim 1, wherein the measuring unit comprises: a wiring having terminals connected to contacts in the conductive material layer; and an electrode disposed in the processing liquid within the processing tank; the measuring unit comprises at least one of a galvanometer, a resistor meter, and a capacitance meter; the galvanometer measures the current flowing between the contacts and the electrodes; the resistor meter measures the resistance between the contacts and the electrodes; and the capacitance meter measures the capacitance between the contacts and the electrodes.

3. The substrate processing apparatus as described in claim 2, wherein the surface of the aforementioned contact portion other than the portion that contacts the aforementioned terminal is protected by a contact portion protective layer.

4. The substrate processing apparatus as described in claim 2, wherein the aforementioned terminals are corrosion resistant.

5. The substrate processing apparatus as described in claim 4, further comprising: a terminal sealing member for surrounding the terminal with a predetermined gas when the terminal is in contact with the contact portion.

6. The substrate processing apparatus as described in claim 4, wherein the aforementioned terminals are formed of carbon.

7. The substrate processing apparatus as described in claim 4, wherein the surface of the aforementioned terminal other than the portion that contacts the aforementioned contact portion is protected by a terminal protective layer.

8. The substrate processing apparatus as described in claim 1, wherein the aforementioned control unit outputs a warning signal in at least one of the cases where the aforementioned current value exceeds a predetermined threshold value and the aforementioned resistance value is lower than a predetermined threshold value.

9. The substrate processing apparatus as described in claim 1, wherein the substrate holding portion comprises: a mounting portion for mounting a plurality of the aforementioned substrates; and a back plate disposed at one end of the mounting portion and extending vertically along the sidewall of the aforementioned processing groove.

10. The substrate processing apparatus described in any one of claims 1 to 9, wherein the aforementioned substrate member is made of quartz material; and the aforementioned protective layer is made of perfluoroalkoxyalkane or polychlorotrifluoroethylene.

11. A substrate processing apparatus for immersing a substrate in a processing liquid and performing surface treatment, comprising: a processing tank for storing the processing liquid; a substrate holding portion for holding the substrate at a predetermined position in the processing liquid within the processing tank, wherein at least in the portion to be immersed in the processing liquid, a conductive material layer and a protective layer are sequentially deposited on the surface of a substrate member from the side of the substrate member; a first protective electrode and a second protective electrode having an electrode protective layer deposited on the surface of the conductive material, wherein the thickness and composition of the electrode protective layer are the same as the thickness and composition of the protective layer of the substrate holding portion, and wherein the first protective electrode and the second protective electrode are immersed in the processing liquid when the substrate holding portion holds the substrate at a predetermined position in the processing liquid within the processing tank; a measuring unit for measuring the capacitance between the first protective electrode and the second protective electrode during the surface treatment; and a control unit for detecting the occurrence of an abnormality in the substrate holding portion based on the capacitance.

12. A substrate processing method for immersing a substrate in a processing liquid and performing surface treatment in a substrate processing apparatus; the substrate processing apparatus comprising: a processing tank for storing the processing liquid; a substrate holding unit for holding the substrate at a predetermined position in the processing liquid within the processing tank, and having a conductive material layer and a protective layer sequentially laminated on the surface of a substrate member from the side of the substrate member, at least in the portion to be immersed in the processing liquid; and a measuring unit for measuring, during the surface treatment, at least one of the following three: a current value flowing between the conductive material layer and the processing liquid; a resistance value between the conductive material layer and the processing liquid; and a capacitance value between an electrode disposed in the processing liquid within the processing tank and the conductive material layer; the substrate processing method comprising the steps of: storing the processing liquid in the processing tank; and holding the substrate at a predetermined position in the processing liquid by the substrate holding unit; The aforementioned substrate processing method further includes the following steps: in parallel with the step of holding the aforementioned substrate in the aforementioned processing liquid, measuring at least one of the following three in the aforementioned surface treatment when a potential difference is generated between the aforementioned conductive material layer and the aforementioned processing liquid in which the aforementioned substrate is immersed in the aforementioned processing tank: the current value flowing between the aforementioned conductive material layer and the aforementioned processing liquid; the resistance value between the aforementioned conductive material layer and the aforementioned processing liquid; and the capacitance between the electrode disposed in the aforementioned processing liquid in the aforementioned processing tank and the aforementioned conductive material layer; and detecting the occurrence of an abnormality in the aforementioned substrate holding portion based on at least one of the aforementioned current value, the aforementioned resistance value, and the aforementioned capacitance.

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