Cleaning method of substrate processing apparatus

Abstract

The invention provides a cleaning method of a substrate processing apparatus. The substrate processing apparatus includes: a processing tank capable of accommodating a plurality of substrates and storing a processing liquid; a liquid receiving part for receiving the processing liquid spilled from the processing tank; and a liquid receiving part discharge pipe for discharging the liquid received by the liquid receiving part. In the cleaning method, when clogging of the liquid receiving portion discharge pipe is detected, a cleaning liquid for removing crystal substances derived from the processing liquid is supplied from a cleaning portion to the liquid receiving portion to remove the crystal substances in the liquid receiving portion discharge pipe and the liquid receiving portion. According to the present invention, in the substrate processing apparatus for batch processing, clogging of the liquid discharge line can be suppressed.

Description

[0001] This application is a divisional application of the patent application filed on October 10, 2020, with application number 202011077702.1 and invention title "Substrate Processing Apparatus and Apparatus Cleaning Method". Technical Field

[0002] This invention relates to a substrate processing apparatus and a method for cleaning the apparatus. Background Technology

[0003] In the prior art, batch processing is performed by immersing a batch (batch substrates) consisting of multiple substrates in a processing tank containing a processing solution.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent document 1: Japanese Patent Application Publication No. 3-38827. Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] This invention provides a technique for suppressing blockage of the drain line in a substrate processing apparatus that performs batch processing.

[0009] Technical means for solving problems

[0010] One embodiment of the substrate processing apparatus of the present invention includes a processing tank, a storage section, a liquid receiving section, a storage section discharge pipe, and a liquid receiving section discharge pipe. The processing tank is capable of accommodating multiple substrates and storing processing liquid. The storage section is connected to the processing tank and stores processing liquid discharged from the processing tank. The liquid receiving section receives processing liquid spilled from the processing tank. The storage section discharges the liquid stored in the storage section. The liquid receiving section discharges the liquid received by the liquid receiving section to an external discharge pipe disposed on the outside. According to the present invention, in a substrate processing apparatus performing batch processing, clogging of the drainage lines can be suppressed.

[0011] The effects of the invention

[0012] According to the present invention, in a substrate processing apparatus that performs batch processing, clogging of the drain line can be suppressed. Attached Figure Description

[0013] Figure 1 This is a top view of the substrate processing apparatus according to the first embodiment.

[0014] Figure 2 This is a block diagram showing the structure of the etching processing tank in the first embodiment.

[0015] Figure 3This is a diagram showing the structure of the etching processing apparatus according to the first embodiment.

[0016] Figure 4 This is a flowchart illustrating the cleaning process of the first embodiment.

[0017] Figure 5 This is a flowchart illustrating the cleaning process of the first variation.

[0018] Figure 6 This is a flowchart illustrating the cleaning process of the second variation.

[0019] Figure 7 This is a flowchart illustrating the cleaning process of the third variation.

[0020] Figure 8 This is a flowchart illustrating the process of the box discharge procedure in the first embodiment.

[0021] Figure 9 This is a diagram showing the structure of the etching process apparatus according to the second embodiment.

[0022] Figure 10 This is a flowchart illustrating the process of cleaning the box according to the second embodiment.

[0023] Figure 11 This is a flowchart illustrating the branch pipe cleaning process of the second embodiment.

[0024] Figure 12 This is a diagram showing the structure of the etching process apparatus according to the third embodiment.

[0025] Figure 13 This is a diagram showing the structure of the etching process apparatus according to the fourth embodiment.

[0026] Figure 14 This is a diagram showing the structure of the cleaning section in the fourth variation.

[0027] Figure 15 This is a diagram showing the structure of the cleaning section in the fifth modified example.

[0028] Explanation of reference numerals in the attached figures

[0029] W chip

[0030] 1. Substrate processing device

[0031] 60 Etching Processing Equipment

[0032] 61 Processing tank

[0033] 200 Liquid receiving section

[0034] 201 First liquid receiving section

[0035] 202 Second liquid receiving section

[0036] 210 Liquid receiving section discharge pipe

[0037] 211 First liquid receiving section discharge pipe

[0038] 212 Second liquid receiving section discharge pipe

[0039] 220 Treatment tank discharge pipe

[0040] 230 Cooling Box

[0041] 240 Cleaning Department

[0042] 243 DIW supply pipe

[0043] 244 HF supply pipe

[0044] 245 DIW Flow Regulator

[0045] 246 HF Flow Regulator

[0046] 260 box discharge pipe Detailed Implementation

[0047] Hereinafter, embodiments of the substrate processing apparatus and apparatus cleaning method of the present invention (hereinafter referred to as "embodiments") will be described in detail with reference to the accompanying drawings. However, the substrate processing apparatus and apparatus cleaning method of the present invention are not limited by these embodiments. Furthermore, the embodiments can be appropriately combined within a range that does not contradict the processing content. In the following embodiments, the same reference numerals are used to denote the same parts, and repeated descriptions are omitted.

[0048] In addition, in the figures referred to below, for ease of explanation, the X-axis, Y-axis and Z-axis directions are sometimes indicated as mutually orthogonal, with the positive Z-axis direction being an orthogonal coordinate system that is vertically upward.

[0049] (First Embodiment)

[0050] <Structure of the Substrate Processing Device>

[0051] First, refer to Figure 1 The structure of the substrate processing apparatus of the first embodiment will be described. Figure 1 This is a top view of the substrate processing apparatus 1 according to the first embodiment.

[0052] like Figure 1 As shown, the substrate processing apparatus 1 of the first embodiment includes: a carrier feeding and discharging unit 2, a first batch forming unit 3, a batch placing unit 4, a batch conveying unit 5, a batch processing unit 6, and a control unit 7.

[0053] The carrier feeding and discharging unit 2 includes: a carrier stage 20, a carrier conveying mechanism 21, carrier stock 22 and 23, and a carrier placement platform 24.

[0054] The carrier stage 20 holds multiple carriers 9 transported from the outside. Each carrier 9 is a container that holds multiple (e.g., 25) wafers W arranged vertically in a horizontal orientation. The carrier transport mechanism 21 transports the carriers 9 between the carrier stage 20, carrier libraries 22 and 23, and carrier placement stage 24.

[0055] Multiple wafers W, before processing, are transported from the carrier 9 placed on the carrier stage 24 to the batch processing unit 6 using the substrate transport mechanism 30 (described later). Conversely, multiple processed wafers W are transported from the batch processing unit 6 to the carrier 9 placed on the carrier stage 24 using the substrate transport mechanism 30.

[0056] The batch forming unit 3 has a substrate transport mechanism 30 for forming batches. A batch consists of multiple (e.g., 50 wafers) of wafers W that can be processed simultaneously by combining wafers W housed in one or more carriers 9. The multiple wafers W forming a batch are arranged at a certain interval with their wafer faces facing each other.

[0057] The substrate transport mechanism 30 transports multiple wafers W between the carrier 9 placed on the carrier stage 24 and the batch placement section 4.

[0058] The batch placement unit 4 has a batch transport stage 40, which holds (and holds) batches transported by the batch transport unit 5 between the batch forming unit 3 and the batch processing unit 6. The batch transport stage 40 has an infeed-side batch placement stage 41 for holding batches formed by the batch forming unit 3 before processing and an outfeed-side batch placement stage 42 for holding batches processed by the batch processing unit 6. Multiple wafers W of one batch are placed in a front-to-back arrangement in an upright position on the infeed-side batch placement stage 41 and the outfeed-side batch placement stage 42.

[0059] The batch transport unit 5 has a batch transport mechanism 50, which transports batches between the batch placement unit 4 and the batch processing unit 6 or inside the batch processing unit 6. The batch transport mechanism 50 has a track 51, a moving body 52, and a substrate holder 53.

[0060] Track 51 is arranged along the X-axis, spanning batch placement section 4 and batch processing section 6. Moving body 52 is capable of holding multiple wafers W and moving them along track 51. Substrate holder 53 is provided on moving body 52 to hold multiple wafers W arranged in an upright position.

[0061] The batch processing unit 6 processes multiple wafers W arranged in a vertical position as a batch, performing etching, cleaning, and drying processes. In the batch processing unit 6, two etching processing devices 60, a cleaning processing device 70, a substrate holder cleaning processing device 80, and a drying processing device 90 are arranged along the track 51.

[0062] Etching apparatus 60 performs batch etching. Cleaning apparatus 70 performs batch cleaning. Substrate holder cleaning apparatus 80 performs substrate holder 53 cleaning. Drying apparatus 90 performs batch drying. The number of etching apparatus 60, cleaning apparatus 70, substrate holder cleaning apparatus 80, and drying apparatus 90 is not limited to [specific number missing]. Figure 1 Examples.

[0063] The etching processing apparatus 60 includes an etching processing tank 61, a rinsing processing tank 62, and substrate lifting mechanisms 63 and 64.

[0064] The processing tank 61 is capable of holding a batch of wafers W arranged in an upright position and stores an etching solution (hereinafter also referred to as "etching solution"). Details of the processing tank 61 are described later.

[0065] The processing tank 62 contains a rinsing solution (pure water, etc.). Multiple wafers W forming a batch are held in a front-to-back arrangement in an upright posture by the substrate lifting mechanisms 63 and 64.

[0066] The etching process apparatus 60 uses a substrate lifting mechanism 63 to hold the batches conveyed by the batch transport unit 5, immersing them in the etching solution in the processing tank 61 for etching. The etching process lasts for, for example, 1 to 3 hours.

[0067] The batches that have undergone etching in processing tank 61 are transported to processing tank 62 by batch transport unit 5. Then, the etching processing apparatus 60 holds the transported batches with substrate lifting mechanism 64 and immerses them in the rinsing liquid of processing tank 62 for rinsing. The batches that have undergone rinsing in processing tank 62 are transported to processing tank 71 of cleaning processing apparatus 70 by batch transport unit 5.

[0068] The cleaning process apparatus 70 includes a cleaning tank 71, a rinsing tank 72, and substrate lifting mechanisms 73 and 74. The cleaning tank 71 contains a cleaning solution (e.g., SC-1 (a mixture of ammonia, hydrogen peroxide, and water)).

[0069] The rinsing tank 72 contains a rinsing solution (pure water, etc.). Multiple wafers W in a batch are held in a standing position, arranged back and forth, in the substrate lifting mechanisms 73 and 74.

[0070] The cleaning treatment device 70 uses a substrate lifting mechanism 73 to hold the batches conveyed by the batch conveying unit 5, immersing them in the cleaning solution in the treatment tank 71 for cleaning treatment.

[0071] The batches that have undergone cleaning in the processing tank 71 are transported to the processing tank 72 by the batch transport unit 5. Then, the cleaning processing device 70 holds the transported batches with the substrate lifting mechanism 74 and immerses them in the rinsing liquid in the processing tank 72 for rinsing. The batches that have undergone rinsing in the processing tank 72 are then transported to the processing tank 91 of the drying processing device 90 by the batch transport unit 5.

[0072] The drying apparatus 90 includes a processing tank 91 and a substrate lifting mechanism 92. A drying processing gas (e.g., IPA (isopropyl alcohol)) is supplied to the processing tank 91. In the substrate lifting mechanism 92, a batch of multiple wafers W are held in an upright position, arranged back and forth.

[0073] The drying process apparatus 90 uses a substrate lifting mechanism 92 to hold the batches conveyed by the batch transport unit 5, and performs drying processing using a drying gas supplied to the processing tank 91. The batches that have undergone drying processing in the processing tank 91 are then transported by the batch transport unit 5 to the batch placement unit 4.

[0074] The substrate holder cleaning and processing apparatus 80 supplies a cleaning solution to the substrate holder 53 of the batch conveying mechanism 50, and then supplies a drying gas, thereby performing a cleaning process on the substrate holder 53.

[0075] The control unit 7 controls the operation of each part of the substrate processing apparatus 1 (carrier feeding / discharging unit 2, batch forming unit 3, batch loading unit 4, batch transport unit 5, and batch processing unit 6). The control unit 7 controls the operation of each part of the substrate processing apparatus 1 based on signals from switches, various sensors, etc.

[0076] The control unit 7 is, for example, a computer, and has a computer-readable storage medium 8. The storage medium 8 stores programs for controlling various processes to be executed in the substrate processing device 1.

[0077] The control unit 7 controls the operation of the substrate processing device 1 by reading and executing a program stored in the storage medium 8. The program can be stored in a computer-readable storage medium 8, or it can be installed from that storage medium into the storage medium 8 of the control unit 7.

[0078] Storage media 8 that can be read by a computer include, for example, hard disks (HD), floppy disks (FD), optical discs (CD), magneto-optical discs (MO), memory cards, etc.

[0079] <Structure of the etching treatment tank>

[0080] Next, refer to Figure 2 The etching treatment tank 61 will be described. Figure 2 This is a block diagram showing the structure of the etching processing tank 61 in the first embodiment.

[0081] In processing tank 61, an etching process is performed, that is, the silicon nitride film (SiN) and silicon oxide film (SiO2) formed on wafer W are selectively etched using a prescribed etching solution. In the etching process, a solution containing a silicon (Si) compound and adjusted for silicon concentration in an aqueous phosphoric acid (H3PO4) solution is used as the etching solution.

[0082] As a method for adjusting the silicon concentration in the etching solution, one can use a method of immersing a dummy substrate in phosphoric acid to dissolve the silicon (seasoning), or a method of dissolving a silicon-containing compound such as silica gel in an aqueous phosphoric acid solution. Alternatively, an aqueous solution of a silicon-containing compound can be added to the aqueous phosphoric acid solution to adjust the silicon concentration.

[0083] like Figure 2 As shown, the etching processing tank 61 includes an inner tank 101 and an outer tank 102. The inner tank 101 is a box-shaped tank open at the top, which stores etching solution inside. A batch formed from multiple wafers W is immersed in the inner tank 101. The outer tank 102 is open at the top and is disposed around the upper part of the inner tank 101. Excess etching solution flows from the inner tank 101 to the outer tank 102.

[0084] In addition, the processing tank 61 includes a phosphoric acid aqueous solution supply unit 103, a silicon supply unit 104, and a DIW supply unit 105.

[0085] The phosphoric acid aqueous solution supply unit 103 includes a phosphoric acid aqueous solution supply source 131, a phosphoric acid aqueous solution supply line 132, and a flow regulator 133.

[0086] Phosphoric acid solution supply source 131 supplies phosphoric acid solution with a concentration that is concentrated to the required concentration. Phosphoric acid solution supply line 132 is connected to phosphoric acid solution supply source 131 and outer tank 102, supplying phosphoric acid solution from phosphoric acid solution supply source 131 to outer tank 102.

[0087] A flow regulator 133 is installed in the phosphoric acid aqueous solution supply line 132 to regulate the supply amount of phosphoric acid aqueous solution to the external tank 102. The flow regulator 133 consists of an on / off valve, a flow control valve, a flow meter, etc.

[0088] The silicon supply unit 104 includes a silicon supply source 141, a silicon supply line 142, and a flow regulator 143.

[0089] Silicon supply source 141 is a tank for storing aqueous solutions containing silicon compounds. Silicon supply line 142 is connected to silicon supply source 141 and outer tank 102, supplying aqueous solutions containing silicon compounds from silicon supply source 141 to outer tank 102.

[0090] A flow regulator 143 is installed in the silicon supply line 142 to regulate the supply amount of the silicon-containing compound aqueous solution to the outer tank 102. The flow regulator 143 consists of an on / off valve, a flow control valve, a flow meter, etc. By adjusting the supply amount of the silicon-containing compound aqueous solution using the flow regulator 143, the silicon concentration of the etching solution is adjusted.

[0091] The DIW supply unit 105 includes: a DIW supply source 151, a DIW supply line 152, and a flow regulator 153. The DIW supply unit 105 supplies DIW (Deionized Water) to the outer tank 102 to replenish the water evaporated due to the heating of the etching solution.

[0092] The DIW supply line 152 is connected to the DIW supply source 151 and the outer tank 102, and supplies DIW at a specified temperature from the DIW supply source 151 to the outer tank 102.

[0093] A flow regulator 153 is installed in the DIW supply line 152 to regulate the amount of DIW supplied to the outer tank 102. The flow regulator 153 consists of an on / off valve, a flow control valve, a flow meter, etc. By adjusting the amount of DIW supplied using the flow regulator 153, the temperature, phosphoric acid concentration, and silicon concentration of the etching solution are adjusted.

[0094] Additionally, the processing tank 61 includes a circulation section 106. The circulation section 106 circulates the etching solution between the inner tank 101 and the outer tank 102. The circulation section 106 includes: a circulation line 161, a plurality of processing solution supply nozzles 162, a filter 163, a heater 164, and a pump 165.

[0095] The circulation line 161 connects the outer tank 102 and the inner tank 101. One end of the circulation line 161 is connected to the outer tank 102, and the other end of the circulation line 161 is connected to a plurality of treatment fluid supply nozzles 162 disposed inside the inner tank 101.

[0096] A filter 163, a heater 164, and a pump 165 are disposed in circulation line 161. The filter 163 removes impurities from the etching solution flowing in circulation line 161. The heater 164 heats the etching solution flowing in circulation line 161 to a temperature suitable for etching. The pump 165 delivers the etching solution from the outer tank 102 to circulation line 161. The pump 165, heater 164, and filter 163 are disposed sequentially from the upstream side.

[0097] The circulation unit 106 delivers the etching solution from the outer tank 102 to the inner tank 101 via the circulation line 161 and multiple processing liquid supply nozzles 162. The etching solution delivered to the inner tank 101 is sprayed out and flows back to the outer tank 102. In this way, the etching solution circulates between the inner tank 101 and the outer tank 102.

[0098] Alternatively, the circulation section 106 can also heat the etching solution using the heater 164 to bring the etching solution to a boiling state.

[0099] <Peripheral Structure of the Processing Tank>

[0100] Next, refer to Figure 3 The surrounding structure of the processing tank 61 is described. Figure 3 This is a diagram showing the structure of the etching processing apparatus 60 according to the first embodiment.

[0101] like Figure 3 As shown, the etching processing apparatus 60 includes: a liquid receiving section 200, a liquid receiving section discharge pipe 210, a processing tank discharge pipe 220, a cooling tank 230, a cleaning section 240, and a tank discharge pipe 260.

[0102] The liquid receiving section 200 is a container for receiving the etching solution spilled from the processing tank 61. The liquid receiving section 200 includes a first liquid receiving section 201 and a second liquid receiving section 202. "Etching solution spilled from the processing tank 61" refers to etching solution that overflows, scatters, or leaks from the inner tank 101 or outer tank 102 and ends up outside. For example, if the processing tank 61 contains boiling etching solution, sometimes the etching solution may splatter outside the processing tank 61 due to boiling.

[0103] The first liquid receiving part 201 is disposed below the processing tank 61. The first liquid receiving part 201 is, for example, a tray-shaped container that receives etching solution that drips from the processing tank 61 due to overflow or leakage.

[0104] The second liquid receiving section 202 has a larger volume than the first liquid receiving section 201. The second liquid receiving section 202 is a box-shaped container that can internally house the processing tank 61 and the first liquid receiving section 201. The second liquid receiving section 202 receives, for example, etching solution that splashes out of the processing tank 61 due to boiling.

[0105] The lower side of the first liquid-receiving part 201 is connected to a first liquid-receiving part discharge pipe 211 for discharging the etching solution received by the first liquid-receiving part 201. Figure 3 In the example shown, the first liquid receiving part discharge pipe 211 is connected to the lower part of the side surface on the positive X-axis direction of the first liquid receiving part 201.

[0106] The bottom surface 201a of the first liquid receiving portion 201 is inclined toward the first liquid receiving portion discharge pipe 211. That is, the bottom surface 201a of the first liquid receiving portion 201 is formed such that the negative X-axis direction side is higher than the positive X-axis direction side. As a result, the etching solution received by the first liquid receiving portion 201 can be effectively discharged from the first liquid receiving portion 201. In addition, etching solution residue in the first liquid receiving portion 201 can be suppressed.

[0107] The lower side of the second liquid-receiving section 202 is connected to a second liquid-receiving section discharge pipe 212 for discharging the etching solution collected by the second liquid-receiving section 202. Figure 3 In the example shown, the discharge pipe 212 of the second liquid receiving part is connected to the lower part of the side surface on the positive X-axis direction of the second liquid receiving part 202.

[0108] The liquid-receiving section discharge pipe 210 connects the liquid-receiving section 200 and the first external discharge pipe 301, discharging the etching solution collected by the liquid-receiving section 200 to the first external discharge pipe 301. The liquid-receiving section discharge pipe 210 branches upstream into the aforementioned first liquid-receiving section discharge pipe 211 and second liquid-receiving section discharge pipe 212. The first liquid-receiving section discharge pipe 211 is connected to the first liquid-receiving section 201, and the second liquid-receiving section discharge pipe 212 is connected to the second liquid-receiving section 202. Furthermore, the liquid-receiving section discharge pipe 210 connects downstream to the first external discharge pipe 301. The first external discharge pipe 301 is one of the devices 300 installed on a building such as a factory where the substrate processing apparatus 1 is installed. Specifically, the first external discharge pipe 301 is an acid discharge pipe for discharging acidic liquids as waste liquid.

[0109] Alternatively, the liquid-receiving discharge pipe 210 may independently have a first liquid-receiving discharge pipe 211 and a second liquid-receiving discharge pipe 212. In this case, the first liquid-receiving discharge pipe 211 and the second liquid-receiving discharge pipe 212 only need to be connected to the first external discharge pipe 301 on the downstream side.

[0110] The processing tank discharge pipe 220 connects the processing tank 61 (specifically, the inner tank 101) and the cooling tank 230. The processing tank discharge pipe 220 discharges the etching solution stored in the inner tank 101 from the inner tank 101 to the cooling tank 230. An on / off valve 221 for opening and closing the processing tank discharge pipe 220 is provided at the middle of the processing tank discharge pipe 220.

[0111] The cooling tank 230 is connected to the processing tank 61 via the processing tank discharge pipe 220, and temporarily stores the etching solution discharged from the processing tank 61. The cooling tank 230 is equipped with a cooling mechanism such as a coil, which can cool the high-temperature etching solution stored inside.

[0112] A liquid level detection unit 231 is provided in the cooling tank 230. The liquid level detection unit 231 detects the liquid level inside the cooling tank 230. For example, the liquid level detection unit 231 is provided near the bottom surface of the cooling tank 230. By providing the liquid level detection unit 231 at this location, it is possible to detect that there is no liquid or substantially no liquid in the cooling tank 230 when the liquid level is no longer detected by the liquid level detection unit 231. Alternatively, another liquid level detection unit may be provided near the top surface of the cooling tank 230. By providing a liquid level detection unit at such a location, it is possible to detect that the cooling tank 230 is full of liquid.

[0113] In addition, a temperature detection unit 232 is provided in the cooling tank 230. The temperature detection unit 232 detects the temperature of the liquid inside the cooling tank 230.

[0114] The tank discharge pipe 260 is connected to the cooling tank 230 on the upstream side and to the second external discharge pipe 302 on the downstream side. The tank discharge pipe 260 discharges the etching solution stored in the cooling tank 230 from the cooling tank 230 to the second external discharge pipe 302. The second external discharge pipe 302 is one of the devices 300. Specifically, the second external discharge pipe 302 is a recovery pipe for recycling the etching solution discharged from the processing tank 61 for reuse.

[0115] A box opening / closing valve 265 is installed in the middle of the box discharge pipe 260. The box opening / closing valve 265 opens and closes the box discharge pipe 260.

[0116] Additionally, sometimes the etching solution is stored in the processing tank 61 in a boiling state. In this case, the organic additives contained in the etching solution turn into vapor and are released outside the processing tank 61, adhering to the liquid receiving section 200 and the liquid receiving section discharge pipe 210. This vapor also contains silicon, and the silicon-containing additives gel in the liquid receiving section 200 or the liquid receiving section discharge pipe 210, and then dry to become crystals, which sometimes become attached to the liquid receiving section 200 and the liquid receiving section discharge pipe 210. As a result, the liquid receiving section discharge pipe 210 may become blocked.

[0117] On the other hand, the silicon-containing additives released from the processing tank 61 through evaporation do not mix into the processing tank discharge pipe 220, cooling tank 230, and tank discharge pipe 260. Therefore, compared to the liquid receiving section discharge pipe 210, the tank discharge pipe 260 is less prone to crystal formation originating from the etching solution.

[0118] Therefore, in the etching processing apparatus 60 of the first embodiment, the drainage path from the liquid receiving section 200, including the liquid receiving section drainage pipe 210, and the drainage path from the cooling tank 230, including the tank drainage pipe 260, are separated. This prevents liquid potentially mixed with silicon additives from flowing from the liquid receiving section drainage pipe 210 into the tank drainage pipe 260. Consequently, it prevents the tank drainage pipe 260 from being blocked by crystals of silicon additives.

[0119] In this way, the etching process apparatus 60 according to the first embodiment can suppress the blockage of the drain line (tank discharge pipe 260).

[0120] The etching processing apparatus 60 of the first embodiment includes a cleaning section 240 for removing crystals adhering to the drain path from the liquid receiving section 200. The cleaning section 240 supplies cleaning fluid to the liquid receiving section 200 for cleaning the liquid receiving section 200 and the liquid receiving section drain pipe 210.

[0121] The cleaning unit 240 includes a DIW supply source 241 and an HF supply source 242. The DIW supply source 241 supplies DIW. The HF supply source 242 supplies HF (liquid hydrogen fluoride).

[0122] Additionally, the cleaning unit 240 includes: a DIW supply pipe 243, an HF supply pipe 244, a DIW flow regulator 245, an HF flow regulator 246, a first DIW on / off valve 247a, a second DIW on / off valve 247b, a first HF on / off valve 248a, and a second HF on / off valve 248b. Furthermore, the cleaning unit 240 includes: a first mixing unit 249a, a second mixing unit 249b, a first release pipe 250a, and a second release pipe 250b.

[0123] DIW supply pipe 243 is connected to DIW supply source 241. DIW supply pipe 243 branches midway into a first DIW supply pipe 243a and a second DIW supply pipe 243b. The first DIW supply pipe 243a is connected to the first mixing section 249a via a first DIW on / off valve 247a. The second DIW supply pipe 243b is connected to the second mixing section 249b via a second DIW on / off valve 247b.

[0124] HF supply pipe 244 is connected to HF supply source 242. HF supply pipe 244 branches midway into a first HF supply pipe 244a and a second HF supply pipe 244b. The first HF supply pipe 244a is connected to the first mixing section 249a via a first HF on / off valve 248a. The second HF supply pipe 244b is connected to the second mixing section 249b via a second HF on / off valve 248b.

[0125] The DIW flow regulator 245 is located upstream of the branch point of the first DIW supply pipe 243 (between the first DIW supply pipe 243a and the second DIW supply pipe 243b) to regulate the flow rate of DIW flowing in the DIW supply pipe 243. The HF flow regulator 246 is located upstream of the branch point of the first HF supply pipe 244 (between the first HF supply pipe 244a and the second HF supply pipe 244b) to regulate the flow rate of HF flowing in the HF supply pipe 244.

[0126] The first DIW on / off valve 247a is located midway through the first DIW supply pipe 243a, and opens and closes the first DIW supply pipe 243a. The second DIW on / off valve 247b is located midway through the second DIW supply pipe 243b, and opens and closes the second DIW supply pipe 243b. The first HF on / off valve 248a is located midway through the first HF supply pipe 244a, and opens and closes the first HF supply pipe 244a. The second HF on / off valve 248b is located midway through the second HF supply pipe 244b, and opens and closes the second HF supply pipe 244b.

[0127] The first mixing section 249a is connected to the first DIW supply pipe 243a and the first HF supply pipe 244a on the upstream side. The first mixing section 249a mixes DIW supplied from the DIW supply source 241 via the first DIW supply pipe 243a and HF supplied from the HF supply source 242 via the first HF supply pipe 244a.

[0128] The second mixing section 249b is connected to the second DIW supply pipe 243b and the second HF supply pipe 244b on the upstream side. The second mixing section 249b mixes the DIW supplied from the DIW supply source 241 via the second DIW supply pipe 243b and the HF supplied from the HF supply source 242 via the second HF supply pipe 244b.

[0129] The first release pipe 250a is connected to the first mixing section 249a on the upstream side, and releases the DHF (dilute hydrofluoric acid) of the DIW and HF mixture generated by the first mixing section 249a to the bottom surface 201a of the first receiving section 201. Specifically, the first release pipe 250a can release DIW when the first DIW on / off valve 247a is open and the first HF on / off valve 248a is closed. Conversely, the first release pipe 250a can release HF when the first DIW on / off valve 247a is closed and the first HF on / off valve 248a is open.

[0130] The second release pipe 250b is connected to the second mixing section 249b on the upstream side, and releases the dilute DHF generated by the second mixing section 249b to the bottom surface 202a of the second receiving section 202. Specifically, when the second DIW on / off valve 247b is open and the second HF on / off valve 248b is closed, the second release pipe 250b can release DIW. Conversely, when the second DIW on / off valve 247b is closed and the second HF on / off valve 248b is open, the second release pipe 250b can release HF.

[0131] The HF contained in the cleaning solution can dissolve the silicon-containing additives released as vapor from the processing tank 61, as well as silicon-based crystals such as SiO2 precipitated due to the temperature drop of the etching solution, as described later. Therefore, by supplying DHF as the cleaning solution to the liquid receiving section 200, the silicon-based crystals adhering to the liquid receiving section 200 can be dissolved and removed from the liquid receiving section 200. Furthermore, the cleaning solution supplied to the liquid receiving section 200 flows in the liquid receiving section discharge pipe 210. Therefore, by supplying DHF as the cleaning solution to the liquid receiving section 200, the silicon-based crystals adhering to the liquid receiving section discharge pipe 210 can be dissolved and removed from the liquid receiving section discharge pipe 210.

[0132] In this way, the etching processing apparatus 60 of the first embodiment can dissolve the silicon-based crystals adhering to the liquid receiving section 200 and the liquid receiving section discharge pipe 210 by supplying a cleaning solution containing HF to the liquid receiving section 200. Therefore, according to the etching processing apparatus 60 of the first embodiment, the discharge path of the etching solution can be suppressed, specifically, the blockage of the liquid receiving section discharge pipe 210 can be suppressed.

[0133] <Cleaning Process>

[0134] Figure 4 This is a flowchart illustrating the cleaning process of the first embodiment. The etching apparatus 60 is executed under the control of the control unit 7. Figure 4 The processing flow is shown below.

[0135] like Figure 4 As shown, the etching processing apparatus 60 first releases DHF to the liquid receiving section 200 (step S001). Specifically, the etching processing apparatus 60 opens the first DIW on / off valve 247a, the second DIW on / off valve 247b, the first HF on / off valve 248a, and the second HF on / off valve 248b. This supplies DIW and HF to the first mixing section 249a, and the DHF mixed by the first mixing section 249a is supplied to the first liquid receiving section 201 from the first release pipe 250a. Additionally, DIW and HF are supplied to the second mixing section 249b, and the DHF mixed by the second mixing section 249b is supplied to the second liquid receiving section 202 from the second release pipe 250b.

[0136] Next, the etching process apparatus 60 releases DIW to the liquid receiving section 200 by closing the first HF on / off valve 248a and the second HF on / off valve 248b (step S002). Afterward, the etching process apparatus 60 stops releasing DIW to the liquid receiving section 200 by closing the first DIW on / off valve 247a and the second DIW on / off valve 247b (step S003), thus ending the cleaning process.

[0137] In this way, the etching process apparatus 60 can also release DIW into the liquid receiving section 200 after releasing DHF into the liquid receiving section 200 to end the cleaning process. This helps to suppress the presence of residual DHF in the liquid receiving section 200 and the liquid receiving section discharge pipe 210.

[0138] Next, refer to Figures 5-7 Another example of the above cleaning process will be described. Figure 5 This is a flowchart illustrating the cleaning process of the first variation. Figure 6 This is a flowchart illustrating the cleaning process of the second variation. Figure 7 This is a flowchart illustrating the cleaning process of the third modified example. The etching apparatus 60 executes the process under the control of the control unit 7. Figures 5-7 The processing flow is shown below.

[0139] like Figure 5 As shown, the etching process apparatus 60 first opens each of the on / off valves 247a, 247b, 248a, and 248b, thereby releasing a first concentration of DHF to the first liquid receiving section 201 and the second liquid receiving section 202 (step S101). The first concentration of DHF is obtained by adjusting the flow rates of DIW and HF using the DIW flow regulator 245 and the HF flow regulator 246.

[0140] Next, the etching process apparatus 60 releases a second concentration of DHF, which is lower than the first concentration, into the first liquid receiving section 201 and the second liquid receiving section 202 (step S102). For example, the etching process apparatus 60 can generate a second concentration of DHF by changing the flow ratio of DIW and HF using the DIW flow regulator 245 and the HF flow regulator 246.

[0141] In this way, the etching process apparatus 60 can release a first concentration of DHF with a higher HF concentration into the liquid receiving section 200, and then release a second concentration of DHF with a lower HF concentration into the liquid receiving section 200. This suppresses HF consumption and effectively cleans the liquid receiving section 200 and the liquid receiving section discharge pipe 210.

[0142] Next, the etching processing apparatus 60 releases DIW to the first liquid receiving section 201 and the second liquid receiving section 202 by closing the first HF on / off valve 248a and the second HF on / off valve 248b (step S103). Afterward, the etching processing apparatus 60 stops releasing DIW to the first liquid receiving section 201 and the second liquid receiving section 202 by closing the first DIW on / off valve 247a and the second DIW on / off valve 247b, thus ending the cleaning process (step S104).

[0143] As another example Figure 6As shown, the etching processing apparatus 60 first opens each of the on / off valves 247a, 247b, 248a, and 248b, thereby releasing DHF to the first liquid receiving section 201 and the second liquid receiving section 202 (step S201). Then, the etching processing apparatus 60 stops releasing DHF to the first liquid receiving section 201 and the second liquid receiving section 202 by closing each of the on / off valves 247a, 247b, 248a, and 248b (step S202).

[0144] Next, the etching processing apparatus 60 determines whether the processing in steps S201 and S202 has been repeated a set number of times (step S203). In this process, if the number of times the processing in steps S201 and S202 has been repeated has not reached the set number of times (step S203, No), the etching processing apparatus 60 returns to step S201 and repeats the processing in steps S201 and S202.

[0145] On the other hand, in step S203, if it is determined that the processes of steps S201 and S202 have been repeated a set number of times (step S203, Yes), the etching processing apparatus 60 releases DIW to the first liquid receiving section 201 and the second liquid receiving section 202 by closing the first HF on / off valve 248a and the second HF on / off valve 248b (step S204). Afterwards, the etching processing apparatus 60 stops releasing DIW to the first liquid receiving section 201 and the second liquid receiving section 202 by closing the first DIW on / off valve 247a and the second DIW on / off valve 247b, thus ending the cleaning process (step S205).

[0146] In this way, the etching apparatus 60 can also intermittently release DHF to the liquid receiving section 200. This disrupts the flow of DHF compared to continuous release, thereby increasing the physical force required to peel silicon-based crystals from the liquid receiving section 200.

[0147] Furthermore, the etching process apparatus 60 can repeat steps S204 and S205 a predetermined number of times. That is, the etching process apparatus 60 can intermittently discharge DHF and intermittently release DIW. In this case, the etching process apparatus 60 can make the interval between stopping the release of DIW and resuming the release of DIW shorter than the interval between stopping the release of DHF and resuming the release of DHF. As a result, residual DHF in the liquid receiving section 200 and the liquid receiving section discharge pipe 210 can be more reliably suppressed.

[0148] As another example, such as Figure 7As shown, the etching processing apparatus 60 first opens the first HF on / off valve 248a and the second HF on / off valve 248b, thereby releasing HF to the first liquid receiving section 201 and the second liquid receiving section 202 (step S301). In this case, the etching processing apparatus 60 stops releasing HF to the first liquid receiving section 201 and the second liquid receiving section 202 by closing the first HF on / off valve 248a and the second HF on / off valve 248b (step S302).

[0149] Next, the etching processing apparatus 60 closes the first HF on / off valve 248a and the second HF on / off valve 248b, and opens the first DIW on / off valve 247a and the second DIW on / off valve 247b. As a result, the etching processing apparatus 60 releases DIW to the first liquid receiving section 201 and the second liquid receiving section 202 (step S303). Afterwards, the etching processing apparatus 60 stops releasing DIW to the first liquid receiving section 201 and the second liquid receiving section 202 by closing the first DIW on / off valve 247a and the second DIW on / off valve 247b (step S304).

[0150] Next, the etching processing apparatus 60 determines whether the processes in steps S301 to S304 have been repeated a predetermined number of times (step S305). In this process, if the number of times steps S301 to S304 have been repeated has not reached the predetermined number (step S305, No), the etching processing apparatus 60 returns to step S301 and repeats steps S301 to S304. On the other hand, in step S305, if it is determined that the processes in steps S301 to S304 have been repeated a predetermined number of times (step S305, Yes), the etching processing apparatus 60 ends the cleaning process.

[0151] In this way, the etching process apparatus 60 can also alternately release HF and DIW into the liquid receiving section 200. In this case, by mixing HF and DIW in the liquid receiving section 200, DHF can be generated in the liquid receiving section 200.

[0152] In this case, HF is released to the liquid receiving section 200 before DIW is released, but the etching processing apparatus 60 can also release DIW to the liquid receiving section 200 before releasing HF. In this case, it can be determined in step S305 that after a set number of repetitions, the cleaning process can be ended after releasing DIW to the liquid receiving section 200 for a certain period of time.

[0153] <Example of box discharge processing>

[0154] Next, refer to Figure 8 An example of the operation of discharging the etching solution stored in the cooling tank 230 into the second external discharge pipe 302 will be described. Figure 8This is a flowchart illustrating the box discharge process of the first embodiment. The etching process apparatus 60 is executed under the control of the control unit 7. Figure 8 The processing flow is shown below.

[0155] like Figure 8 As shown, the control unit 7 determines whether the liquid level in the cooling tank 230 is detected by the liquid level detection unit 231 (step S401). If the determination is that the liquid level is detected by the liquid level detection unit 231 (step S401, yes), the control unit 7 determines whether the liquid temperature in the cooling tank 230 detected by the temperature detection unit 232 is lower than a threshold (step S402). If the determination is that the liquid temperature is lower than the threshold (step S402, yes), the control unit 7 discharges the etching solution stored in the cooling tank 230 to the second external discharge pipe 302 through the tank discharge pipe 260 by opening the tank opening / closing valve 265 (step S403). On the other hand, if the liquid level is not detected by the liquid level detection unit 231 in step S401 (step S401, no), or if the liquid temperature is above the threshold in step S402 (step S402, no), the control unit 7 returns the process to step S401.

[0156] For example, when the on / off valve 221 is opened to replace the liquid in the treatment tank 61 (see reference). Figure 3 At this time, a large amount of etching solution stored in the processing tank 61 flows into the cooling tank 230 all at once. As a result, the liquid level detection unit 231 detects the liquid level. Furthermore, since the etching solution stored in the processing tank 61 is at a high temperature, the liquid temperature detected by the temperature detection unit 232 is above the threshold. Therefore, at this moment, the tank opening / closing valve 265 does not open. Later, when the etching solution in the cooling tank 230 is cooled by the cooling mechanism of the cooling tank 230, the liquid temperature detected by the temperature detection unit 232 is below the threshold. Therefore, the tank opening / closing valve 265 opens, and the etching solution in the cooling tank 230 is discharged to the second external discharge pipe 302 via the tank discharge pipe 260.

[0157] In this way, in the etching processing apparatus 60, the high-temperature etching solution discharged from the processing tank 61 is cooled by the cooling box 230 and then discharged to the second external discharge pipe 302, which is one of the devices 300. The processing order of steps S401 and S402 can also be reversed.

[0158] When step S403 is completed, the control unit 7 determines whether the liquid level in the cooling tank 230 is no longer detected by the liquid level detection unit 231 (step S404). If the determination is that the liquid level detection unit 231 no longer detects the liquid level (step S404, yes), the control unit 7 closes the tank opening / closing valve 265 (step S405). On the other hand, if the liquid level detection unit 231 detects the liquid level in step S404 (step S404, no), the control unit 7 returns the process to step S404 and repeats the determination process of step S404 until the liquid level is no longer detected. When step S405 is completed, the control unit 7 ends the tank discharge process.

[0159] (Second Implementation)

[0160] Next, refer to Figure 2 The structure of the etching process apparatus of the ninth embodiment will be described. Figure 9 This is a diagram showing the structure of the etching process apparatus according to the second embodiment.

[0161] like Figure 9 As shown, the etching processing apparatus 60A of the second embodiment includes a liquid receiving section discharge pipe 210A and a tank discharge pipe 260A.

[0162] The liquid receiving and discharge pipe 210A includes a branch pipe 213, a switching section 214, and a temperature detection section 215.

[0163] Branch pipe 213 connects the middle section of liquid receiving section discharge pipe 210A to cooling tank 230, and discharges the liquid flowing in liquid receiving section discharge pipe 210A to cooling tank 230. Specifically, branch pipe 213 is located downstream of the confluence point of the first liquid receiving section discharge pipe 211 and the second liquid receiving section discharge pipe 212.

[0164] The switching unit 214 switches the destination of the liquid flowing in the liquid receiving outlet pipe 210A between the first external outlet pipe 301 and the cooling tank 230. The temperature detection unit 215 detects the temperature of the liquid flowing in the liquid receiving outlet pipe 210A. Based on the detection result of the temperature detection unit 215, if the liquid temperature in the liquid receiving outlet pipe 210A exceeds a threshold, the control unit 7 can control the switching unit 214 to switch the destination of the liquid from the first external outlet pipe 301 to the cooling tank 230. This prevents high-temperature liquid from flowing into the first external outlet pipe 301.

[0165] In addition, this example shows the case where the temperature detection unit 215 is located downstream of the switching unit 214, but the temperature detection unit 215 may also be located upstream of the switching unit 214.

[0166] The tank discharge pipe 260A includes a first tank discharge pipe 261 and a second tank discharge pipe 262. The first tank discharge pipe 261 connects the cooling tank 230 and the second external discharge pipe 302. A first tank opening / closing valve 266 is provided at the middle of the first tank discharge pipe 261 to open and close the first tank discharge pipe 261.

[0167] The second tank discharge pipe 262 is connected to the first tank discharge pipe 261 on the upstream side and to the third external discharge pipe 303 on the downstream side. The second tank discharge pipe 262 discharges the liquid stored in the cooling tank 230 to the third external discharge pipe 303. The third external discharge pipe 303 is one of the devices 300. Specifically, the third external discharge pipe 303, like the first external discharge pipe 301, is an acid discharge pipe used to discharge acidic liquids as waste liquid. Alternatively, the second tank discharge pipe 262 can also be connected to the first external discharge pipe 301.

[0168] A second tank opening / closing valve 267 and a cooling section 268 are provided midway through the second tank discharge pipe 262. The second tank opening / closing valve 267 opens and closes the second tank discharge pipe 262. The cooling section 268 cools the liquid flowing in the second tank discharge pipe 262, for example, by supplying cooling water to the inside of the second tank discharge pipe 262.

[0169] In this way, in the etching processing apparatus 60A of the second embodiment, the liquid receiving section discharge pipe 210A is branched and connected to the cooling tank 230. As a result, the cleaning fluid supplied from the cleaning section 240 can be supplied to the cooling tank 230 via the liquid receiving section discharge pipe 210A and the branch pipe 213, so the cooling tank 230 and the tank discharge pipe 260A can be cleaned with the cleaning fluid.

[0170] When the temperature of the etching solution decreases, silicon-containing compounds (e.g., SiO2) dissolved in the etching solution may precipitate. Therefore, crystals originating from the etching solution may adhere to the cooling tank 230 and the tank discharge pipe 260A, for example. According to the etching processing apparatus 60A of the second embodiment, the cooling tank 230 and the tank discharge pipe 260A can be cleaned with a cleaning solution, thus preventing clogging not only of the liquid receiving section discharge pipe 210A but also of the tank discharge pipe 260A.

[0171] Furthermore, according to the etching processing apparatus 60A of the second embodiment, the cleaning fluid flowing into the cooling tank 230 can be discharged to the third external discharge pipe 303 via the second tank discharge pipe 262. Therefore, it is possible to prevent the cleaning fluid from mixing into the etching fluid recovered and reused from the cooling tank 230 via the first tank discharge pipe 261.

[0172] Next, the cleaning process of the second embodiment will be described. First, refer to... Figure 10 The process for cleaning the tank discharge pipe 260A is explained. Figure 10This is a flowchart illustrating the process of the box cleaning procedure in the second embodiment. The etching apparatus 60A is executed under the control of the control unit 7. Figure 10 The processing flow is shown below.

[0173] like Figure 10 As shown, the control unit 7 monitors the time from the opening to the closing of the first tank opening / closing valve 266 (step S501). Specifically, the first tank opening / closing valve 266 is equivalent to the tank opening / closing valve 265 in the first embodiment, and it opens when the liquid level in the cooling tank 230 is detected by the liquid level detection unit 231 and the liquid temperature detected by the temperature detection unit 232 is less than a threshold. Then, the first tank opening / closing valve 266 closes when the liquid level in the cooling tank 230 is no longer detected by the liquid level detection unit 231. That is, the control unit 7 monitors the time from the opening to the closing of the first tank opening / closing valve 266 as the time required until the etchant in the cooling tank 230 is completely discharged. Hereinafter, this required time will be referred to as the "liquid level drop time".

[0174] As described above, the cooling tank 230 stores the etching solution discharged from the processing tank 61, and the amount of etching solution discharged from the processing tank 61 is approximately the same each time. Therefore, as long as there is no blockage in the tank discharge pipe 260A, the liquid level drop time is approximately the same each time.

[0175] Next, the control unit 7 determines whether the liquid level drop time exceeds a threshold (step S502). If the liquid level drop time exceeds the threshold in this determination (step S502, yes), the control unit 7 controls the switching unit 214 to switch the outflow destination of the liquid flowing in the liquid receiving section discharge pipe 210A from the first external discharge pipe 301 to the cooling tank 230 (step S503). In addition, the control unit 7 switches the outflow destination of the liquid from the cooling tank 230 from the second external discharge pipe 302 to the third external discharge pipe 303 by closing the first tank opening / closing valve 266 and opening the second tank opening / closing valve 267 (step S504).

[0176] Then, the control unit 7 performs a cleaning process (step S505). Specifically, the cleaning process in step S505 is, for example, Figures 4-7 Any of the cleaning processes shown.

[0177] In this manner, if the liquid level drop time exceeds a threshold, the etching process 60A determines that the tank discharge pipe 260A is blocked and initiates a tank cleaning process. This allows for the cleaning of the cooling tank 230 and the tank discharge pipe 260A at appropriate times.

[0178] Next, refer to Figure 11 The process for cleaning branch pipe 213 is described. Figure 11This is a flowchart illustrating the branch pipe cleaning process of the second embodiment. The etching apparatus 60A is executed under the control of the control unit 7. Figure 11 The processing flow is shown below.

[0179] Furthermore, under normal circumstances where no branch pipe cleaning is performed, the destination of the liquid discharged from the liquid receiving section 200 is switched to the cooling tank 230. That is, the liquid received by the liquid receiving section 200 is stored in the cooling tank 230 through the branch pipe 213. In this case, when the liquid level in the cooling tank 230 is detected by the liquid level detection unit 231 and the liquid temperature detected by the temperature detection unit 232 is lower than the threshold, the first tank opening / closing valve 266 is opened, and liquid is discharged from the cooling tank 230.

[0180] like Figure 11 As shown, the control unit 7 monitors the time from when the liquid level detection unit 231 no longer detects the liquid level in the cooling tank 230 until it is detected again (step S601). That is, the control unit 7 monitors the time required for the liquid level in the cooling tank 230 to rise due to the liquid discharged from the cooling tank 230 via the branch pipe 213, until the liquid level is detected by the liquid level detection unit 231. Hereinafter, this required time will be referred to as the "liquid level rise time". The amount of liquid discharged per unit time via the branch pipe 213 is approximately constant. Therefore, as long as there is no blockage in the branch pipe 213 or the liquid receiving drain pipe 210A, the liquid level rise time is approximately the same each time.

[0181] Next, the control unit 7 determines whether the liquid level rise time exceeds a threshold (step S602). If the determination indicates that the liquid level rise time exceeds the threshold (step S602, Yes), the control unit 7 closes the first tank opening / closing valve 266 and opens the second tank opening / closing valve 267. As a result, the control unit 7 switches the outflow destination of the liquid from the cooling tank 230 from the second external discharge pipe 302 to the third external discharge pipe 303 (step S603).

[0182] Then, the control unit 7 performs a cleaning process (step S604). The cleaning process in step S604 is, for example,... Figures 4-7 Any of the cleaning processes shown.

[0183] In this way, if the liquid level rise time exceeds a threshold, the etching processing apparatus 60A determines that the branch pipe 213 or the liquid receiving drain pipe 210A is blocked and starts the branch pipe cleaning process. As a result, the branch pipe 213 or the liquid receiving drain pipe 210A can be cleaned at the appropriate time.

[0184] (Third implementation)

[0185] Next, refer to Figure 3The structure of the etching process apparatus of the 12th embodiment will be described. Figure 12 This is a diagram showing the structure of the etching process apparatus according to the third embodiment.

[0186] like Figure 12 As shown, the etching processing apparatus 60B of the third embodiment includes a gas purge unit 270.

[0187] The gas purging unit 270 blows gas into the interior of the liquid receiving section discharge pipe 210. Specifically, the gas purging unit 270 includes: a gas supply source 271, a first supply pipe 272, a second supply pipe 273, and on / off valves 275 and 276. The gas supply source 271 supplies, for example, N2 gas. The gas supplied from the gas supply source 271 can be dry air or other inert gas, or it can be an inert gas other than N2 gas. The first supply pipe 272 is connected to the gas supply source 271 on its upstream side. In addition, the downstream end of the first supply pipe 272 is located near the inlet of the first liquid receiving section discharge pipe 211. The first supply pipe 272 blows the gas supplied from the gas supply source 271 into the interior of the first liquid receiving section discharge pipe 211.

[0188] The second supply pipe 273 is connected to the gas supply source 271 on its upstream side. Furthermore, the downstream end of the second supply pipe 273 is positioned near the inlet of the second liquid-receiving discharge pipe 212. The second supply pipe 273 blows gas supplied from the gas supply source 271 into the interior of the second liquid-receiving discharge pipe 212. An on / off valve 275 is located midway through the first supply pipe 272 to open and close the first supply pipe 272. Similarly, an on / off valve 276 is located midway through the second supply pipe 273 to open and close the second supply pipe 273.

[0189] In this manner, the etching processing apparatus 60B uses a gas purging unit 270 to blow gas into the interior of the first liquid receiving section discharge pipe 211 and the second liquid receiving section discharge pipe 212. As a result, crystals adhering to the interior of the first liquid receiving section discharge pipe 211 and the second liquid receiving section discharge pipe 212 can be physically peeled off from the first liquid receiving section discharge pipe 211 and the second liquid receiving section discharge pipe 212.

[0190] Therefore, according to the etching process apparatus 60B, clogging of the drain line can be further suppressed.

[0191] (Fourth implementation)

[0192] Next, refer to Figure 4 The structure of the etching process apparatus of the 13th embodiment will be described. Figure 13 This is a diagram showing the structure of the etching process apparatus according to the fourth embodiment.

[0193] like Figure 13As shown, the etching processing apparatus 60C of the fourth embodiment also includes an exhaust section 280 for venting the interior of the second liquid receiving section 202.

[0194] The exhaust section 280 includes: an intake section 281 disposed above the processing tank 61 inside the second liquid receiving section 202; an exhaust pipe 282 connected to the intake section 281; and a suction device 283 disposed on the exhaust pipe 282. The exhaust section 280 uses the suction force generated by the suction device 283 to draw in the silicon-mixed additive, which is released as vapor from the processing tank 61, from the intake section 281, and discharges it to the outside of the second liquid receiving section 202 via the exhaust pipe 282. Therefore, the silicon-mixed additive is less likely to adhere to the first liquid receiving section 201, the second liquid receiving section 202, and the liquid receiving section discharge pipe 210, thus suppressing blockage of the liquid receiving section discharge pipe 210 caused by the crystallization of the silicon-mixed additive.

[0195] A gas-liquid separator 284 is provided midway through the exhaust section 280 to separate the vapor flowing through the exhaust pipe 282 into gas and liquid. The gas-liquid separator 284 is connected to the aforementioned cleaning section 240, from which cleaning fluid is supplied. Furthermore, the gas-liquid separator 284 is connected to a drain pipe 285. The drain pipe 285 is connected downstream to a liquid-receiving discharge pipe 210, discharging the liquid accumulated in the gas-liquid separator 284 into the liquid-receiving discharge pipe 210.

[0196] By configuring it in this way, it is possible to prevent the silicon-containing additives discharged from the second liquid receiving section 202 from crystallizing in the exhaust section 280 and clogging the exhaust pipe 282. In addition, by connecting the drain pipe 285 to the liquid receiving section discharge pipe 210, for example, the piping structure can be simplified compared to the case of directly connecting the gas-liquid separator 284 and the first external discharge pipe 301.

[0197] (Fifth implementation)

[0198] In the fifth embodiment, refer to Figure 14 and Figure 15 A modified example of the cleaning section will be explained. Figure 14 This is a diagram showing the structure of the cleaning section in the fourth variation. Figure 15 This is a diagram showing the structure of the cleaning section in the fifth modified example.

[0199] like Figure 14 As shown, the cleaning section 240D of the fourth modification includes a release section 251. The release section 251 is connected to the downstream end of the first release tube 250a.

[0200] The release part 251 is disposed on the upper side of the inclined bottom surface 201a of the first liquid receiving part 201, in other words, it is disposed above the side opposite to the side where the discharge pipe 211 of the first liquid receiving part is provided. By being disposed in this position, DHF and the like can flow along the inclined bottom surface 201a, thus increasing the flow rate of DHF and the like. In this way, by increasing the flow rate of DHF and the like, foreign matter adhering to the first liquid receiving part 201 and the like can be removed more effectively.

[0201] The release section 251 includes a plurality of release ports 251a. The plurality of release ports 251a are arranged in a horizontal direction (orthogonal to the horizontal direction extending at an angle, in this case, the Y-axis direction) along the width direction of the inclined bottom surface 201a. In this way, by arranging a plurality of release ports 251a along the width direction of the bottom surface 201a, DHF and the like can be sufficiently and completely distributed to the first liquid receiving section 201.

[0202] like Figure 15 As shown, the cleaning section 240E of the fifth modification includes a plurality of release sections 252. The plurality of release sections 252 are connected to the downstream end of the first release tube 250a. Figure 15 In the example shown, the cleaning unit 240E includes two release units 252. One of the two release units 252 is disposed on one side of the bottom surface 201a in the width direction, and the other of the two release units 252 is disposed on the other side of the bottom surface 201a in the width direction.

[0203] The release section 252 includes a plurality of release ports 252a. The plurality of release ports 252a extend in a horizontal direction (horizontal component of the inclined direction) along the bottom surface 201a, and are arranged in an X-axis direction. In this way, by arranging the plurality of release ports 252a in the inclined direction along the bottom surface 201a, which is an inclined surface, the first liquid receiving section 201 can be cleaned more effectively.

[0204] As described above, the substrate processing apparatus of the embodiments (for example, etching processing apparatuses 60, 60A-60C) includes: a processing tank (for example, processing tank 61), a storage section (for example, cooling tank 230), a liquid receiving section (for example, liquid receiving section 200), a storage section discharge pipe (for example, tank discharge pipe 260), and a liquid receiving section discharge pipe (for example, liquid receiving section discharge pipe 210). The processing tank can accommodate multiple substrates (for example, wafers W) and can store processing liquid (for example, etching solution). The storage section is connected to the processing tank and stores the processing liquid discharged from the processing tank. The liquid receiving section receives the processing liquid spilled from the processing tank. The storage section discharges the liquid stored in the storage section. The liquid receiving section discharges the liquid received by the liquid receiving section to an external discharge pipe (for example, first external discharge pipe 301) provided on the outside.

[0205] Therefore, the substrate processing apparatus according to the embodiment can suppress the clogging of the drain line in a substrate processing apparatus that performs batch processing.

[0206] The processing solution may contain phosphoric acid and dissolved silicon-containing compounds (for example, SiO2). When the processing solution is stored in the processing tank in a boiling state, silicon may be released from the processing solution along with steam, potentially forming silicon-like crystals that adhere to the liquid receiving section and the liquid receiving section discharge pipe. On the other hand, since this silicon-containing steam does not enter the storage section and the storage section discharge pipe, silicon-like crystals originating from the processing solution are less likely to form in the storage section discharge pipe compared to the liquid receiving section discharge pipe. Therefore, as shown in the substrate processing apparatus of the embodiment, by separating the drainage path from the liquid receiving section including the liquid receiving section discharge pipe and the drainage path from the storage section including the storage section discharge pipe, it is possible to prevent the storage section discharge pipe from being blocked by silicon-like crystals.

[0207] The substrate processing apparatus of this embodiment may further include: a branch pipe (for example, branch pipe 213), a cleaning unit (for example, cleaning unit 240), and a switching unit (for example, switching unit 214). The branch pipe connects the middle section of the liquid receiving section discharge pipe to the storage section, and discharges the liquid flowing in the liquid receiving section discharge pipe to the storage section. The cleaning unit supplies cleaning fluid to the liquid receiving section to remove crystals originating from the processing liquid. The switching unit switches the destination of the liquid flowing in the liquid receiving section discharge pipe between the external discharge pipe and the storage section.

[0208] When the temperature of the processing solution decreases, silicon-containing compounds (such as SiO2) dissolved in the processing solution may precipitate. Therefore, silicon-like crystals originating from the processing solution may adhere to the storage section and the storage section discharge pipe. In response, the substrate processing apparatus according to the embodiment can clean the storage section and the storage section discharge pipe with a cleaning solution, thus suppressing clogging not only of the liquid receiving section discharge pipe but also of the storage section discharge pipe.

[0209] The cleaning solution may contain a first liquid (for example, pure water) and a second liquid (for example, hydrogen fluoride). The cleaning unit includes: a first liquid supply pipe (for example, DIW supply pipe 243), a second liquid supply pipe (for example, HF supply pipe 244), release pipes (for example, first release pipe 250a and second release pipe 250b), a first liquid flow rate regulating unit (for example, DIW flow rate regulator 245), and a second liquid flow rate regulating unit (for example, HF flow rate regulator 246). The first liquid supply pipe supplies the first liquid. The second liquid supply pipe supplies the second liquid. The release pipe is connected to the first liquid supply pipe and the second liquid supply pipe, supplying the cleaning solution, the first liquid, or the second liquid to the receiving portion. The first liquid flow rate regulating unit is provided in the first liquid supply pipe to regulate the flow rate of the first liquid flowing in the first liquid supply pipe. The second liquid flow rate regulating unit is installed in the second liquid supply pipe to regulate the flow rate of the second liquid flowing in the second liquid supply pipe.

[0210] Therefore, the substrate processing apparatus according to the embodiment can clean the liquid receiving section, the liquid receiving section discharge pipe, the storage section, and the storage section discharge pipe with cleaning fluid supplied from the cleaning section. Thus, clogging of the drainage line can be further suppressed.

[0211] The first liquid can be pure water, and the second liquid can be hydrogen fluoride. The cleaning liquid, namely the hydrogen fluoride contained in dilute hydrofluoric acid, can dissolve, for example, silicon-based crystals originating from the treatment liquid. Therefore, by supplying dilute hydrofluoric acid as a cleaning liquid to the liquid receiving section, the silicon-based crystals adhering to the liquid receiving section can be dissolved and removed from the liquid receiving section. Furthermore, the cleaning liquid supplied to the liquid receiving section flows through the liquid receiving section discharge pipe. Therefore, the silicon-based crystals adhering to the liquid receiving section discharge pipe can be dissolved and removed.

[0212] The substrate processing apparatus of this embodiment may further include a liquid level detection unit (for example, liquid level detection unit 231) for detecting the liquid level in the storage section; and a control unit (for example, control unit 7) for controlling the cleaning section and the switching section. In this case, the control unit can monitor the drop time of the liquid level in the storage section based on the detection results of the liquid level detection unit. If the drop time exceeds a threshold, the control unit controls the switching section to switch the outflow destination to the storage section, and controls the cleaning section to supply cleaning fluid to the receiving section. Thus, the cleaning of the storage section and the storage section discharge pipe can be performed at appropriate times.

[0213] The substrate processing apparatus of this embodiment may further include a liquid level detection unit (for example, liquid level detection unit 231) for detecting the liquid level in the storage section; and a control unit (for example, control unit 7) for controlling the cleaning section and the switching section. In this case, the control unit can monitor the rise time of the liquid level in the storage section based on the detection result of the liquid level detection unit when the outflow destination is switched to the storage section, and control the cleaning section to supply cleaning fluid to the receiving section if the rise time exceeds a threshold. Thus, cleaning of the branch pipe and the discharge pipe of the receiving section can be performed at appropriate times.

[0214] The substrate processing apparatus of the embodiment may further include a gas purging unit (as an example, gas purging unit 270) that blows gas into the interior of the liquid receiving portion discharge pipe. This allows for the physical removal of crystals adhering to the interior of the liquid receiving portion discharge pipe. Therefore, blockage of the discharge line can be further suppressed.

[0215] The liquid receiving section may include a first liquid receiving section (for example, the first liquid receiving section 201) disposed below the processing tank and a second liquid receiving section (for example, the second liquid receiving section 202) capable of receiving the processing tank and the first liquid receiving section. In this case, the substrate processing apparatus of the embodiment may also include an exhaust section (for example, an exhaust section 280) for venting the interior of the second liquid receiving section. By venting the silicon-mixed vapor released from the processing tank to the outside of the second liquid receiving section through the exhaust section, clogging of the liquid receiving section's discharge pipe can be further suppressed.

[0216] It should be considered that all points in the embodiments disclosed in this application are illustrative and not limiting. In fact, the above embodiments can be implemented in a variety of ways. In addition, the above embodiments can be omitted, substituted, or modified in various ways without departing from the claims and their intent.

Claims

1. A cleaning method for a substrate processing apparatus, characterized in that, The substrate processing apparatus includes: A processing tank capable of accommodating multiple substrates and storing processing fluid; The liquid receiving section that receives the treatment liquid spilled from the treatment tank; and The liquid receiving part discharge pipe discharges the liquid collected by the liquid receiving part. In the cleaning method, if a blockage is detected in the discharge pipe of the liquid receiving section, a cleaning solution for removing crystals originating from the treatment liquid is supplied from the cleaning section to the liquid receiving section to remove the crystals in the discharge pipe of the liquid receiving section and the liquid receiving section.

2. The cleaning method of the substrate processing apparatus as described in claim 1, characterized in that, The blockage is detected by monitoring the drop or rise time of the liquid level by the liquid level detection unit before supplying the cleaning fluid to the liquid receiving section.

3. The cleaning method of the substrate processing apparatus as described in claim 1 or 2, characterized in that, The cleaning solution is a dilute hydrogen fluoride aqueous solution with variable concentration. The concentration is controlled according to the amount and type of crystals attached to the object being cleaned.

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