Substrate processing apparatus and apparatus cleaning method

Abstract

A substrate processing apparatus 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 housing a plurality of substrates and storing a processing liquid. 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 discharge pipe discharges the liquid stored in the storage section. The liquid receiving section discharge pipe discharges the liquid received by the liquid receiving section to an external discharge pipe provided outside. According to the present invention, in a substrate processing apparatus that performs batch processing, clogging of a liquid discharge line can be suppressed.

Description

TECHNICAL FIELD

[0001] The present application relates to a substrate processing apparatus and an apparatus cleaning method. BACKGROUND

[0002] In the related art, a batch process in which a batch of substrates (batch substrates) composed of a plurality of substrates is immersed in a processing tank in which a processing liquid is stored, and a batch of substrates is processed at one time.

[0003] Related Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 3-38827 SUMMARY

[0006] Problems to be Solved by the Invention

[0007] The present application provides a technology capable of suppressing clogging of a liquid discharge line in a substrate processing apparatus in which a batch process is performed.

[0008] Means of Solving the Problems

[0009] A substrate processing apparatus of one embodiment of the present application includes a processing tank, a storage portion, a liquid receiving portion, a storage portion discharge pipe, and a liquid receiving portion discharge pipe. The processing tank can accommodate a plurality of substrates and store a processing liquid. The storage portion is connected to the processing tank and stores the processing liquid discharged from the processing tank. The liquid receiving portion receives the processing liquid spilled from the processing tank. The storage portion discharge pipe discharges the liquid stored in the storage portion. The liquid receiving portion discharge pipe discharges the liquid received by the liquid receiving portion to an external discharge pipe provided outside. According to the present application, clogging of a liquid discharge line can be suppressed in a substrate processing apparatus in which a batch process is performed.

[0010] Effects of the Invention

[0011] According to the present application, clogging of a liquid discharge line can be suppressed in a substrate processing apparatus in which a batch process is performed. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 FIG. 1 is a plan view of a substrate processing apparatus of Embodiment 1.

[0013] Figure 2 FIG. 3 is a block diagram showing the structure of a processing tank for etching of Embodiment 1.

[0014] Figure 3 FIG. 4 is a diagram showing the structure of an etching processing apparatus of Embodiment 1.

[0015] Figure 4 FIG. 6 is a flowchart showing the flow of a cleaning process of Embodiment 1.

[0016] Figure 5 is a flowchart showing a flow of the cleaning process of the first modification example.

[0017] Figure 6 is a flowchart showing a flow of the cleaning process of the second modification example.

[0018] Figure 7 is a flowchart showing a flow of the cleaning process of the third modification example.

[0019] Figure 8 is a flowchart showing a flow of the tank discharge process of the first embodiment.

[0020] Figure 9 is a view showing a structure of the etching processing apparatus of the second embodiment.

[0021] Figure 10 is a flowchart showing a flow of the tank cleaning process of the second embodiment.

[0022] Figure 11 is a flowchart showing a flow of the branch pipe cleaning process of the second embodiment.

[0023] Figure 12 is a view showing a structure of the etching processing apparatus of the third embodiment.

[0024] Figure 13 is a view showing a structure of the etching processing apparatus of the fourth embodiment.

[0025] Figure 14 is a view showing a structure of the cleaning section of the fourth modification example.

[0026] Figure 15 is a view showing a structure of the cleaning section of the fifth modification example.

[0027] Explanation of Reference Numerals

[0028] W wafer

[0029] 1 substrate processing apparatus

[0030] 60 etching processing apparatus

[0031] 61 processing tank

[0032] 200 liquid receiving section

[0033] 201 first liquid receiving section

[0034] 202 second liquid receiving section

[0035] 210 liquid receiving section discharge pipe

[0036] 211 first liquid receiving section discharge pipe

[0037] 212 second liquid receiving portion discharge pipe

[0038] 220 processing tank discharge pipe

[0039] 230 cooling tank

[0040] 240 cleaning section

[0041] 243 DIW supply pipe

[0042] 244 HF supply pipe

[0043] 245 DIW flow rate regulator

[0044] 246 HF flow rate regulator

[0045] 260 tank discharge pipe DETAILED DESCRIPTION

[0046] Hereinafter, embodiments (hereinafter referred to as "embodiments") of the substrate processing apparatus and the apparatus cleaning method of the present application will be described in detail with reference to the accompanying drawings. Note that the substrate processing apparatus and the apparatus cleaning method of the present application are not limited by the embodiments. In addition, each of the embodiments can be appropriately combined within a range not causing the processing contents to contradict each other. In addition, the same reference symbols are attached to the same portions in each of the embodiments below, and overlapping descriptions will be omitted.

[0047] In addition, in each of the drawings referred to below, in order to easily describe, sometimes a right-angle coordinate system in which an X-axis direction, a Y-axis direction, and a Z-axis direction orthogonal to each other are defined, and a Z-axis positive direction is a vertical upward direction is shown.

[0048] (First Embodiment)

[0049] Structure of Substrate Processing Apparatus

[0050] First, with reference to Figure 1 The structure of the substrate processing apparatus of the first embodiment will be described. Figure 1 is a plan view of the substrate processing apparatus 1 of the first embodiment.

[0051] As shown in Figure 1 , the substrate processing apparatus 1 of the first embodiment includes a carrier in-out section 2, a first batch forming section 3, a batch placement section 4, a batch conveying section 5, a batch processing section 6, and a control section 7.

[0052] The carrier in-out section 2 includes a carrier stage 20, a carrier conveying mechanism 21, carrier stocks 22, 23, and a carrier placement stage 24.

[0053] The carrier table 20 places a plurality of carriers 9 that are transported from the outside. The carrier 9 is a container that houses a plurality of (for example, 25) wafers W in a horizontal posture in a vertical arrangement. The carrier transport mechanism 21 transports the carriers 9 between the carrier table 20, the carrier storage 22, 23, and the carrier placement table 24.

[0054] From the carriers 9 placed on the carrier placement table 24, a plurality of wafers W before processing are delivered to the batch processing section 6 by the substrate transport mechanism 30 described later. In addition, a plurality of wafers W after processing are delivered from the batch processing section 6 to the carriers 9 placed on the carrier placement table 24 by the substrate transport mechanism 30.

[0055] The batch forming section 3 has the substrate transport mechanism 30 that forms a batch. The batch is composed of a plurality of (for example, 50) wafers W that can be processed simultaneously by combining the wafers W housed in one or a plurality of carriers 9. The plurality of wafers W that form one batch are arranged at a certain interval in a state in which the wafer faces of the wafers W face each other.

[0056] The substrate transport mechanism 30 transports a plurality of wafers W between the carriers 9 placed on the carrier placement table 24 and the batch placement section 4.

[0057] The batch placement section 4 has a batch transport table 40 that places a batch (places it on standby) transported by the batch transport section 5 between the batch forming section 3 and the batch processing section 6. The batch transport table 40 has an incoming-side batch placement table 41 that places a batch before processing formed by the batch forming section 3 and an outgoing-side batch placement table 42 that places a batch after processing processed by the batch processing section 6. On the incoming-side batch placement table 41 and the outgoing-side batch placement table 42, a plurality of wafers W of one batch are placed in a vertical posture in a front-and-back arrangement.

[0058] The batch transport section 5 has a batch transport mechanism 50 that transports a batch between the batch placement section 4 and the batch processing section 6 or inside the batch processing section 6. The batch transport mechanism 50 has a track 51, a moving body 52, and a substrate holding body 53.

[0059] The track 51 is disposed in the X-axis direction across the batch placement section 4 and the batch processing section 6. The moving body 52 can move while holding a plurality of wafers W along the track 51. The substrate holding body 53 is provided to the moving body 52 and holds a plurality of wafers W arranged in a vertical posture in a front-and-back arrangement.

[0060] The batch processing section 6 performs etching processing, cleaning processing, drying processing, and the like on a plurality of wafers W arranged in a vertical posture in a front-and-back arrangement as one batch. In the batch processing section 6, two etching processing devices 60, a cleaning processing device 70, a substrate holding body cleaning processing device 80, and a drying processing device 90 are arranged in a line along the track 51.

[0061] The etching processing apparatus 60 performs batch etching processing. The cleaning processing apparatus 70 performs batch cleaning processing. The substrate holder cleaning processing apparatus 80 performs cleaning processing of the substrate holder 53. The drying processing apparatus 90 performs batch drying processing. The number of the etching processing apparatus 60, the cleaning processing apparatus 70, the substrate holder cleaning processing apparatus 80, and the drying processing apparatus 90 is not limited to Figure 1 Examples.

[0062] The etching processing apparatus 60 includes a processing tank 61 for etching, a processing tank 62 for rinsing, and substrate lifting mechanisms 63, 64.

[0063] The processing tank 61 is capable of accommodating one batch of wafers W arranged in a standing posture, and stores a processing liquid for etching (hereinafter also referred to as "etching liquid"). Details of the processing tank 61 are described later.

[0064] A processing liquid for rinsing (pure water or the like) is stored in the processing tank 62. A plurality of wafers W forming a batch are held in the standing posture in front and back arrangement by the substrate lifting mechanisms 63, 64.

[0065] The etching processing apparatus 60 holds the batch delivered by the batch delivery section 5 with the substrate lifting mechanism 63, and immerses it in the etching liquid of the processing tank 61, thereby performing etching processing. The etching processing is performed for, for example, one to three hours.

[0066] The batch subjected to the etching processing in the processing tank 61 is delivered to the processing tank 62 by the batch delivery section 5. Then, the etching processing apparatus 60 holds the delivered batch with the substrate lifting mechanism 64, and immerses it in the rinsing liquid of the processing tank 62, thereby performing rinsing processing. The batch subjected to the rinsing processing in the processing tank 62 is delivered to the processing tank 71 of the cleaning processing apparatus 70 by the batch delivery section 5.

[0067] The cleaning processing apparatus 70 includes a processing tank 71 for cleaning, a processing tank 72 for rinsing, and substrate lifting mechanisms 73, 74. A processing liquid for cleaning (for example, SC-1 (a mixture of ammonia, hydrogen peroxide, and water) or the like) is stored in the processing tank 71 for cleaning.

[0068] A processing liquid for rinsing (pure water or the like) is stored in the processing tank 72 for rinsing. A plurality of wafers W forming a batch are held in the standing posture in front and back arrangement by the substrate lifting mechanisms 73, 74.

[0069] The cleaning processing apparatus 70 holds the batch delivered by the batch delivery section 5 with the substrate lifting mechanism 73, and immerses it in the cleaning liquid of the processing tank 71, thereby performing cleaning processing.

[0070] The batch, on which the cleaning process has been performed in the process tank 71, is transported to the process tank 72 by the batch transport section 5. Then, the cleaning process apparatus 70 holds the transported batch by the substrate lifting mechanism 74 so as to be immersed in the rinse liquid in the process tank 72, thereby performing the rinse process. The batch, on which the rinse process has been performed in the process tank 72, is transported to the process tank 91 of the dry process apparatus 90 by the batch transport section 5.

[0071] The dry process apparatus 90 has the process tank 91 and the substrate lifting mechanism 92. The process tank 91 is supplied with a dry process gas (e.g., IPA (isopropyl alcohol) or the like) for drying. The substrate lifting mechanism 92 holds a plurality of wafers W of one batch in a standing posture in a row.

[0072] The dry process apparatus 90 holds the batch transported by the batch transport section 5 by the substrate lifting mechanism 92, and performs the dry process using the dry process gas supplied into the process tank 91. The batch, on which the dry process has been performed in the process tank 91, is transported to the batch placement section 4 by the batch transport section 5.

[0073] The substrate holder cleaning process apparatus 80 supplies the substrate holder 53 of the batch transport mechanism 50 with a cleaning process liquid and further with a dry gas, thereby performing the cleaning process of the substrate holder 53.

[0074] The control section 7 controls the operation of each section (the carrier feeding and discharging section 2, the batch formation section 3, the batch placement section 4, the batch transport section 5, the batch process section 6) of the substrate processing apparatus 1. The control section 7 controls the operation of each section of the substrate processing apparatus 1 based on signals of switches, various sensors, and the like.

[0075] The control section 7 is, for example, a computer, and has a computer-readable storage medium 8. A program for controlling various processes to be performed in the substrate processing apparatus 1 is stored in the storage medium 8.

[0076] The control section 7 controls the operation of the substrate processing apparatus 1 by causing the program stored in the storage medium 8 to be read and executed. The program can be stored in the storage medium 8 which is readable by the computer, or can be installed from the storage medium to the storage medium 8 of the control section 7.

[0077] The storage medium 8 which is readable by the computer is, for example, a hard disk (HD), a floppy disk (FD), a compact disc (CD), a magneto-optical disk (MO), a memory card, or the like.

[0078] < Structure of Process Tank for Etching >

[0079] Next, the structure of the process tank 61 for etching will be described with reference to Figure 2 The process tank 61 for etching will be described. Figure 2 is a block diagram showing the structure of the process tank 61 for etching of the first embodiment.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] The silicon supply unit 104 includes a silicon supply source 141, a silicon supply line 142, and a flow regulator 143.

[0088] 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.

[0089] A flow regulator 143 is provided to the silicon supply line 142, and regulates the supply amount of the aqueous silicon compound solution supplied to the outer tank 102. The flow regulator 143 is configured by an on-off valve, a flow control valve, a flow meter, or the like. By regulating the supply amount of the aqueous silicon compound solution using the flow regulator 143, the silicon concentration of the etching solution is regulated.

[0090] The DIW supply section 105 has a DIW supply source 151, a DIW supply line 152, and a flow regulator 153. The DIW supply section 105 supplies DIW (DeIonized Water) to the outer tank 102 in order to replenish moisture evaporated due to heating of the etching solution.

[0091] The DIW supply line 152 is connected to the DIW supply source 151 and the outer tank 102, and supplies DIW at a prescribed temperature from the DIW supply source 151 to the outer tank 102.

[0092] The flow regulator 153 is provided to the DIW supply line 152, and regulates the supply amount of the DIW supplied to the outer tank 102. The flow regulator 153 is configured by an on-off valve, a flow control valve, a flow meter, or the like. By regulating the supply amount of the DIW using the flow regulator 153, the temperature, the phosphoric acid concentration, and the silicon concentration of the etching solution are regulated.

[0093] In addition, 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 liquid supply nozzles 162, a filter 163, a heater 164, and a pump 165.

[0094] 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 the plurality of processing liquid supply nozzles 162 disposed inside the inner tank 101.

[0095] The filter 163, the heater 164, and the pump 165 are provided to the circulation line 161. The filter 163 removes impurities from the etching solution flowing in the circulation line 161. The heater 164 heats the etching solution flowing in the circulation line 161 to a temperature suitable for etching processing. The pump 165 sends the etching solution in the outer tank 102 out to the circulation line 161. The pump 165, the heater 164, and the filter 163 are provided in this order from the upstream side.

[0096] The circulation section 106 sends the etching solution from the outer tank 102 to the inner tank 101 via the circulation line 161 and the plurality of processing liquid supply nozzles 162. The etching solution sent to the inner tank 101 is splashed from the inner tank 101 and flows out again to the outer tank 102. In this way, the etching solution is circulated between the inner tank 101 and the outer tank 102.

[0097] Further, the circulation section 106 can also bring the etching liquid to a boiling state by heating the etching liquid with the heater 164.

[0098] <Periphery structure of the processing tank>

[0099] Next, the periphery structure of the processing tank 61 will be described with reference to Figure 3 The periphery structure of the processing tank 61 will be described. Figure 3 is a view showing the structure of the etching processing apparatus 60 according to the first embodiment.

[0100] As shown in Figure 3 , 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.

[0101] The liquid receiving section 200 is a container that receives the etching liquid 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. Here, the "etching liquid spilled from the processing tank 61" refers to the etching liquid that runs out of the inner tank 101 or the outer tank 102 due to overflow, scattering, or leakage from the inner tank 101 or the outer tank 102. For example, in the case where the processing tank 61 stores the etching liquid in a boiling state, the etching liquid can sometimes scatter outside the processing tank 61 due to boiling.

[0102] The first liquid receiving section 201 is disposed below the processing tank 61. The first liquid receiving section 201 is, for example, a disc-shaped container that receives the etching liquid, for example, that drips from the processing tank 61 due to overflow or leakage from the processing tank 61.

[0103] The second liquid receiving section 202 has a larger capacity than the first liquid receiving section 201. The second liquid receiving section 202 is a box-shaped container that can accommodate the processing tank 61 and the first liquid receiving section 201 inside. The second liquid receiving section 202 receives, for example, the etching liquid that scatters from the processing tank 61 due to boiling.

[0104] The side lower portion of the first liquid receiving section 201 is connected to the first liquid receiving section discharge pipe 211 that discharges the etching liquid received by the first liquid receiving section 201 from the first liquid receiving section 201. In the example shown in Figure 3 , the first liquid receiving section discharge pipe 211 is connected to the side lower portion of the first liquid receiving section 201 on the positive direction side of the X axis.

[0105] The bottom surface 201a of the first liquid receiving section 201 is inclined toward the first liquid receiving section discharge pipe 211. That is, the bottom surface 201a of the first liquid receiving section 201 is formed so as to be higher on the negative direction side of the X axis than on the positive direction side of the X axis. Thereby, the etching liquid received by the first liquid receiving section 201 can be effectively discharged from the first liquid receiving section 201. Further, the etching liquid can be inhibited from remaining inside the first liquid receiving section 201.

[0106] The lower side of the side surface of the second liquid receiving portion 202 is connected to a second liquid receiving portion discharge pipe 212 for discharging the etching liquid received by the second liquid receiving portion 202 from the second liquid receiving portion 202. In Figure 3 In the example shown, the second liquid receiving portion discharge pipe 212 is connected to the lower side of the side surface of the second liquid receiving portion 202 on the positive direction side of the X axis.

[0107] The liquid receiving portion discharge pipe 210 connects the liquid receiving portion 200 and the first external discharge pipe 301, and discharges the etching liquid received by the liquid receiving portion 200 to the first external discharge pipe 301. The liquid receiving portion discharge pipe 210 is branched on the upstream side into the first liquid receiving portion discharge pipe 211 and the second liquid receiving portion discharge pipe 212 described above, the first liquid receiving portion discharge pipe 211 is connected to the first liquid receiving portion 201, and the second liquid receiving portion discharge pipe 212 is connected to the second liquid receiving portion 202. In addition, the liquid receiving portion discharge pipe 210 is connected to the first external discharge pipe 301 on the downstream side. 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 liquid discharge pipe for discharging a liquid of an acid type as waste liquid.

[0108] In addition, the liquid receiving portion discharge pipe 210 can also independently have the first liquid receiving portion discharge pipe 211 and the second liquid receiving portion discharge pipe 212. In this case, the first liquid receiving portion discharge pipe 211 and the second liquid receiving portion discharge pipe 212 can be connected to the first external discharge pipe 301 on the downstream side.

[0109] 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 liquid stored in the inner tank 101 from the inner tank 101 to the cooling tank 230. A valve 221 that opens and closes the processing tank discharge pipe 220 is provided at an intermediate portion of the processing tank discharge pipe 220.

[0110] The cooling tank 230 is connected to the processing tank 61 via the processing tank discharge pipe 220, and temporarily stores the etching liquid discharged from the processing tank 61. A cooling mechanism such as a coil pipe is provided in the cooling tank 230, and the etching liquid stored in the inside can be cooled.

[0111] A liquid level detecting portion 231 is provided in the cooling tank 230. The liquid level detecting portion 231 detects the liquid level in the cooling tank 230. For example, the liquid level detecting portion 231 is provided near the bottom surface of the cooling tank 230. By providing the liquid level detecting portion 231 at this position, 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 detecting portion 231. In addition, in the cooling tank 230, another liquid level detecting portion can also be provided near the top surface of the cooling tank 230. By providing the liquid level detecting portion at such a position, it is possible to detect that the liquid in the cooling tank 230 is full.

[0112] Further, a temperature detecting portion 232 is provided in the cooling tank 230. The temperature detecting portion 232 detects the temperature of the liquid in the cooling tank 230.

[0113] The tank discharge pipe 260 is connected to the cooling tank 230 at the upstream side, and is connected to the second external discharge pipe 302 at the downstream side. The tank discharge pipe 260 discharges the etching liquid 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 apparatuses 300. Specifically, the second external discharge pipe 302 is a recovery pipe for recovering the etching liquid discharged from the processing tank 61 for reuse.

[0114] A tank opening and closing valve 265 is provided in the middle of the tank discharge pipe 260. The tank opening and closing valve 265 opens and closes the tank discharge pipe 260.

[0115] Further, sometimes the etching liquid is stored in the processing tank 61 in a boiling state. In this case, the organic additive contained in the etching liquid becomes vapor and is released outside the processing tank 61 to adhere to the liquid receiving portion 200 and the liquid receiving portion discharge pipe 210. The vapor also contains silicon, and the additive mixed with the silicon is gelled in the liquid receiving portion 200 or the liquid receiving portion discharge pipe 210, and further dries to become a crystalline substance, and sometimes is fixed to the liquid receiving portion 200 and the liquid receiving portion discharge pipe 210. Thus, the liquid receiving portion discharge pipe 210 can be clogged.

[0116] On the other hand, the additive mixed with the silicon released by evaporation from the processing tank 61 does not mix into the processing tank discharge pipe 220, the cooling tank 230, and the tank discharge pipe 260. Therefore, the tank discharge pipe 260 is less likely to be clogged by the crystalline substance derived from the etching liquid than the liquid receiving portion discharge pipe 210.

[0117] Thus, in the etching processing apparatus 60 of the first embodiment, the liquid discharge path from the liquid receiving portion 200 including the liquid receiving portion discharge pipe 210 and the liquid discharge path from the cooling tank 230 including the tank discharge pipe 260 are separated. Thus, it is possible to suppress the liquid possibly mixed with the additive mixed with the silicon from the liquid receiving portion discharge pipe 210 from flowing into the tank discharge pipe 260. Therefore, it is possible to suppress the tank discharge pipe 260 from being clogged by the crystalline substance of the additive mixed with the silicon.

[0118] As described above, according to the etching processing apparatus 60 of the first embodiment, it is possible to suppress the clogging of the liquid discharge line (tank discharge pipe 260).

[0119] The etching processing apparatus 60 of the first embodiment includes a cleaning portion 240 for removing the crystalline substance adhering to the liquid discharge path from the liquid receiving portion 200. The cleaning portion 240 supplies a cleaning liquid for cleaning the liquid receiving portion 200 and the liquid receiving portion discharge pipe 210 to the liquid receiving portion 200.

[0120] The cleaning section 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).

[0121] In addition, the cleaning section 240 includes a DIW supply pipe 243, an HF supply pipe 244, a DIW flow rate regulator 245, an HF flow rate 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. In addition, the cleaning section 240 includes a first mixing section 249a, a second mixing section 249b, a first release pipe 250a, and a second release pipe 250b.

[0122] The DIW supply pipe 243 is connected to the DIW supply source 241. The DIW supply pipe 243 is branched into a first DIW supply pipe 243a and a second DIW supply pipe 243b at an intermediate portion. The first DIW supply pipe 243a is connected to the first mixing section 249a via the first DIW on-off valve 247a. The second DIW supply pipe 243b is connected to the second mixing section 249b via the second DIW on-off valve 247b.

[0123] The HF supply pipe 244 is connected to the HF supply source 242. The HF supply pipe 244 is branched into a first HF supply pipe 244a and a second HF supply pipe 244b at an intermediate portion. The first HF supply pipe 244a is connected to the first mixing section 249a via the first HF on-off valve 248a. The second HF supply pipe 244b is connected to the second mixing section 249b via the second HF on-off valve 248b.

[0124] The DIW flow rate regulator 245 is provided on an upstream side of the DIW supply pipe 243 with respect to a branching point of the first DIW supply pipe 243a and the second DIW supply pipe 243b, and regulates the flow rate of DIW flowing in the DIW supply pipe 243. The HF flow rate regulator 246 is provided on an upstream side of the HF supply pipe 244 with respect to a branching point of the first HF supply pipe 244a and the second HF supply pipe 244b, and regulates the flow rate of HF flowing in the HF supply pipe 244.

[0125] The first DIW on-off valve 247a is provided at an intermediate portion of the first DIW supply pipe 243a, and opens and closes the first DIW supply pipe 243a. The second DIW on-off valve 247b is provided at an intermediate portion of the second DIW supply pipe 243b, and opens and closes the second DIW supply pipe 243b. The first HF on-off valve 248a is provided at an intermediate portion of the first HF supply pipe 244a, and opens and closes the first HF supply pipe 244a. The second HF on-off valve 248b is provided at an intermediate portion of the second HF supply pipe 244b, and opens and closes the second HF supply pipe 244b.

[0126] 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 the DIW supplied from the DIW supply source 241 via the first DIW supply pipe 243a and the HF supplied from the HF supply source 242 via the first HF supply pipe 244a.

[0127] 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.

[0128] The first release pipe 250a is connected to the first mixing section 249a on the upstream side, and releases the DHF (dilute hydrogen fluoride acid) of the mixed solution of the DIW and the HF generated by the first mixing section 249a to the bottom surface 201a of the first liquid receiving section 201. Here, in a case where the first DIW on-off valve 247a is opened and the first HF on-off valve 248a is closed, the first release pipe 250a can release the DIW. In addition, in a case where the first DIW on-off valve 247a is closed and the first HF on-off valve 248a is opened, the first release pipe 250a can release the HF.

[0129] The second release pipe 250b is connected to the second mixing section 249b on the upstream side, and releases the DHF dilute generated by the second mixing section 249b to the bottom surface 202a of the second liquid receiving section 202. Here, in a case where the second DIW on-off valve 247b is opened and the second HF on-off valve 248b is closed, the second release pipe 250b can release the DIW. In addition, in a case where the second DIW on-off valve 247b is closed and the second HF on-off valve 248b is opened, the second release pipe 250b can release the HF.

[0130] The HF contained in the cleaning solution can dissolve the additive mixed with silicon released from the treatment tank 61 as a vapor and the silicon-based crystalline substance such as SiO2 precipitated due to a temperature drop of the etching solution as described later. Therefore, by supplying the DHF as the cleaning solution to the liquid receiving section 200, the silicon-based crystalline substance adhering to the liquid receiving section 200 can be dissolved and removed from the liquid receiving section 200. In addition, the cleaning solution supplied to the liquid receiving section 200 flows in the liquid receiving section discharge pipe 210. Therefore, by supplying the DHF as the cleaning solution to the liquid receiving section 200, the silicon-based crystalline substance adhering to the liquid receiving section discharge pipe 210 can be dissolved and removed from the liquid receiving section discharge pipe 210.

[0131] As such, the etching treatment device 60 of the first embodiment can dissolve the silicon-based crystal adhering to the liquid-receiving section 200 and the liquid-receiving section discharge pipe 210 by supplying the liquid-receiving section 200 with the cleaning liquid containing HF. Therefore, according to the etching treatment device 60 of the first embodiment, it is possible to suppress the discharge path of the etching liquid, specifically, the clogging of the liquid-receiving section discharge pipe 210.

[0132] <Flow of cleaning treatment>

[0133] Figure 4 is a flowchart showing the flow of the cleaning treatment of the first embodiment. Here, the etching treatment device 60 performs the processing flow shown in Figure 4 according to the control of the control section 7.

[0134] As shown in Figure 4 , the etching treatment device 60 first releases DHF to the liquid-receiving section 200 (step S001). Specifically, the etching treatment device 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. Thereby, DIW and HF are supplied to the first mixing section 249a, and DHF mixed by the first mixing section 249a is supplied from the first release pipe 250a to the first liquid-receiving section 201. In addition, DIW and HF are supplied to the second mixing section 249b, and DHF mixed by the second mixing section 249b is supplied from the second release pipe 250b to the second liquid-receiving section 202.

[0135] Next, the etching treatment device 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). After that, the etching treatment device 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) and ends the cleaning treatment.

[0136] As such, the etching treatment device 60 can also end the cleaning treatment by releasing DIW to the liquid-receiving section 200 after releasing DHF to the liquid-receiving section 200. Thereby, it is possible to suppress the residual DHF in the liquid-receiving section 200 and the liquid-receiving section discharge pipe 210.

[0137] Next, another example of the above-described cleaning treatment will be described with reference to Figures 5-7 . Figure 5 is a flowchart showing the flow of the cleaning treatment of the first modification. Figure 6 is a flowchart showing the flow of the cleaning treatment of the second modification. Figure 7 is a flowchart showing the flow of the cleaning treatment of the third modification. Here, the etching treatment device 60 performs the processing flow shown in Figures 5-7 according to the control of the control section 7.

[0138] like Figure 5 As shown, the etching processing 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.

[0139] 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.

[0140] 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.

[0141] 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).

[0142] As another example Figure 6 As 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).

[0143] 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 the processing to step S201 and repeats the processing in steps S201 and S202.

[0144] On the other hand, in a case where it is determined in step S203 that the processes of steps S201 and S202 are repeated for a set number of times (YES in step S203), the etching processing apparatus 60 releases the DIW from the first liquid-receiving portion 201 and the second liquid-receiving portion 202 by closing the first and second HF on-off valves 248a and 248b (step S204). Thereafter, the etching processing apparatus 60 stops the release of the DIW from the first liquid-receiving portion 201 and the second liquid-receiving portion 202 by closing the first and second DIW on-off valves 247a and 247b, and ends the cleaning process (step S205).

[0145] As such, the etching processing apparatus 60 can also intermittently release the DHF from the liquid-receiving portion 200. Thereby, compared to a case where the DHF is continuously released, it is possible to make the flow of the DHF turbulent. Thus, it is possible to increase the physical force with which the silicon-based crystal is peeled from the liquid-receiving portion 200.

[0146] In addition, the etching processing apparatus 60 can also repeat the processes of steps S204 and S205 for a set number of times. That is, the etching processing apparatus 60 can also intermittently release the DIW in addition to intermittently discharging the DHF. In this case, the etching processing apparatus 60 can make the interval from when the release of the DIW is stopped until when the release of the DIW is started shorter than the interval from when the release of the DHF is stopped until when the release of the DHF is started. Thereby, it is possible to more reliably inhibit the DHF from remaining in the liquid-receiving portion 200 and the liquid-receiving portion discharge pipe 210.

[0147] As another example, as shown in FIG. 6, the etching processing apparatus 60 first opens the first and second HF on-off valves 248a and 248b, and thereby releases the HF from the first liquid-receiving portion 201 and the second liquid-receiving portion 202 (step S301). In this case, the etching processing apparatus 60 stops the release of the HF from the first liquid-receiving portion 201 and the second liquid-receiving portion 202 by closing the first and second HF on-off valves 248a and 248b (step S302). Figure 7 Next, the etching processing apparatus 60 closes the first and second HF on-off valves 248a and 248b, and opens the first and second DIW on-off valves 247a and 247b. Thereby, the etching processing apparatus 60 releases the DIW from the first liquid-receiving portion 201 and the second liquid-receiving portion 202 (step S303). Thereafter, the etching processing apparatus 60 stops the release of the DIW from the first liquid-receiving portion 201 and the second liquid-receiving portion 202 by closing the first and second DIW on-off valves 247a and 247b (step S304).

[0148]

[0149] ​Next, the etching treatment device 60 determines whether the processes of steps S301 to S304 are repeated for a set number of times (step S305). In this process, in a case where the number of times the processes of steps S301 to S304 are repeated does not reach the set number of times (step S305, No), the etching treatment device 60 returns the process to step S301 and repeats the processes of steps S301 to S304. On the other hand, in a case where it is determined in step S305 that the processes of steps S301 to S304 are repeated for the set number of times (step S305, Yes), the etching treatment device 60 ends the cleaning process.

[0150] As such, the etching treatment device 60 can also alternately release HF and DIW to the liquid-receiving portion 200. In this case, by mixing HF and DIW in the liquid-receiving portion 200, it is possible to generate DHF in the liquid-receiving portion 200.

[0151] In addition, here, DIW is released after HF is released to the liquid-receiving portion 200, but the etching treatment device 60 can also release HF after DIW is released to the liquid-receiving portion 200. In this case, it is possible to end the cleaning process after DIW is released to the liquid-receiving portion 200 for a certain time after it is determined in step S305 that the processes are repeated for the set number of times.

[0152] <Example of Operation of Tank Discharge Process>

[0153] Next, the tank discharge process will be described with reference to Figure 8 An example of operation of a tank discharge process in which etching solution stored in the cooling tank 230 is discharged to the second external discharge pipe 302 will be described. Figure 8 is a flowchart showing the flow of the tank discharge process of the first embodiment. Here, the etching treatment device 60 performs the process flow shown in Figure 8 in accordance with the control of the control section 7.

[0154] As shown in Figure 8 , the control section 7 determines whether the liquid level in the cooling tank 230 is detected by the liquid level detector 231 (step S401). In a case where it is determined in this determination that the liquid level is detected by the liquid level detector 231 (step S401, Yes), the control section 7 determines whether the liquid temperature in the cooling tank 230 detected by the temperature detector 232 is less than a threshold value (step S402). In a case where it is determined in this determination that the liquid temperature is less than the threshold value (step S402, Yes), the control section 7 discharges the etching solution stored in the cooling tank 230 to the second external discharge pipe 302 via the tank discharge pipe 260 by opening the tank on-off valve 265 (step S403). On the other hand, in a case where the liquid level is not detected by the liquid level detector 231 in step S401 (step S401, No) or the liquid temperature is equal to or greater than the threshold value in step S402 (step S402, No), the control section 7 returns the process to step S401.

[0155] For example, when the opening and closing valve 221 is opened for liquid replacement of the processing tank 61 (refer to Figure 3 ), a large amount of etching liquid stored in the processing tank 61 flows into the cooling tank 230 at one time. Thereby, the liquid level detection section 231 becomes a state where the liquid level is detected. In addition, since the etching liquid stored in the processing tank 61 is high temperature, the liquid temperature detected by the temperature detection section 232 is equal to or higher than the threshold value. Therefore, at this time, the tank opening and closing valve 265 is not opened. After that, when the etching liquid in the cooling tank 230 is cooled by the cooling mechanism provided to the cooling tank 230, the liquid temperature detected by the temperature detection section 232 is lower than the threshold value. Then, the tank opening and closing valve 265 is opened, and the etching liquid in the cooling tank 230 is discharged to the second external discharge pipe 302 via the tank discharge pipe 260.

[0156] As such, in the etching processing apparatus 60, the high temperature etching liquid discharged from the processing tank 61 is cooled by the cooling tank 230, and then discharged to the second external discharge pipe 302 which is one of the facilities 300. Here, the processing order of the steps S401 and S402 can be reversed.

[0157] When the processing of the step S403 ends, the control section 7 determines whether the liquid level in the cooling tank 230 is no longer detected by the liquid level detection section 231 (step S404). In the case where it is determined in this determination that the liquid level is no longer detected by the liquid level detection section 231 (step S404, Yes), the control section 7 closes the tank opening and closing valve 265 (step S405). On the other hand, in the case where the liquid level is detected by the liquid level detection section 231 in the step S404 (step S404, No), the control section 7 returns the processing to the step S404, and repeatedly performs the determination processing of the step S404 until the liquid level becomes undetectable. When the processing of the step S405 ends, the control section 7 ends the tank discharge processing.

[0158] (Second Embodiment)

[0159] Next, the structure of the etching processing apparatus of the ninth embodiment will be described with reference to Figure 2 The etching processing apparatus 60A of the second embodiment includes a liquid receiving section discharge pipe 210A and a tank discharge pipe 260A as shown in Figure 9 is a view showing the structure of the etching processing apparatus of the second embodiment.

[0160] As shown in Figure 9 , the etching processing apparatus 60A of the second embodiment includes a liquid receiving section discharge pipe 210A and a tank discharge pipe 260A.

[0161] The liquid receiving section discharge pipe 210A includes a branch pipe 213, a switching section 214, and a temperature detection section 215.

[0162] The branch pipe 213 connects a middle portion of the liquid- receiving portion discharge pipe 210A and the cooling tank 230, and discharges the liquid flowing in the liquid-receiving portion discharge pipe 210A to the cooling tank 230. Specifically, the branch pipe 213 is provided on a downstream side of a confluence point of the first liquid-receiving portion discharge pipe 211 and the second liquid-receiving portion discharge pipe 212.

[0163] The switching portion 214 switches the discharge destination of the liquid flowing in the liquid-receiving portion discharge pipe 210A between the first external discharge pipe 301 and the cooling tank 230. The temperature detecting portion 215 detects the temperature of the liquid flowing in the liquid-receiving portion discharge pipe 210A. The control portion 7, based on the detection result of the temperature detecting portion 215, can control the switching portion 214 to switch the discharge destination of the liquid from the first external discharge pipe 301 to the cooling tank 230 in a case where the liquid temperature in the liquid-receiving portion discharge pipe 210A exceeds a threshold value. Thereby, it is possible to suppress the inflow of the high-temperature liquid to the first external discharge pipe 301.

[0164] Note that, here, an example in which the temperature detecting portion 215 is provided on the downstream side of the switching portion 214 is shown, but the temperature detecting portion 215 can also be provided on the upstream side of the switching portion 214.

[0165] 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 on-off valve 266 that opens and closes the first tank discharge pipe 261 is provided in a middle portion of the first tank discharge pipe 261.

[0166] The second tank discharge pipe 262 is connected to the first tank discharge pipe 261 on the upstream side and to a 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 liquid discharge pipe for discharging the liquid of the acid type as waste liquid. Note that, the second tank discharge pipe 262 can also be connected to the first external discharge pipe 301.

[0167] A second tank on-off valve 267 and a cooling portion 268 are provided in a middle portion of the second tank discharge pipe 262. The second tank on-off valve 267 opens and closes the second tank discharge pipe 262. The cooling portion 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.

[0168] As such, in the etching treatment apparatus 60A of the second embodiment, the liquid-receiving portion discharge pipe 210A is branched to be connected to the cooling tank 230. Thus, the cleaning liquid supplied from the cleaning portion 240 can be supplied to the cooling tank 230 via the liquid-receiving portion 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 liquid.

[0169] When the temperature of the etching liquid decreases, a silicon-containing compound (e.g., SiO2) dissolved in the etching liquid can precipitate. Thus, for example, the cooling tank 230 and the tank discharge pipe 260A can also have a crystal originating from the etching liquid attached thereto. According to the etching treatment apparatus 60A of the second embodiment, the cooling tank 230 and the tank discharge pipe 260A can be cleaned with the cleaning liquid, so not only the clogging of the liquid-receiving portion discharge pipe 210A but also the clogging of the tank discharge pipe 260A can be suppressed.

[0170] In addition, according to the etching treatment apparatus 60A of the second embodiment, the cleaning liquid flowing into the cooling tank 230 can be discharged to the third external discharge pipe 303 via the second tank discharge pipe 262. Thus, the mixing of the cleaning liquid into the etching liquid recovered from the cooling tank 230 via the first tank discharge pipe 261 for reuse can be suppressed.

[0171] Next, the flow of the cleaning process of the second embodiment will be described. First, the flow of the cleaning process of the first embodiment will be described with reference to Figure 10 The flow of the tank cleaning process in which the tank discharge pipe 260A is cleaned will be described. Figure 10 is a flowchart showing the flow of the tank cleaning process of the second embodiment. Here, the etching treatment apparatus 60A performs the process flow shown in Figure 10 in accordance with the control of the control portion 7.

[0172] As shown in Figure 10 , the control portion 7 monitors the time from the opening to the closing of the first tank on-off valve 266 (step S501). Specifically, the first tank on-off valve 266 corresponds to the tank on-off valve 265 of the first embodiment, and is opened in a case where the liquid level in the cooling tank 230 is detected by the liquid level detector 231 and the liquid temperature detected by the temperature detector 232 is less than a threshold value. Then, the first tank on-off valve 266 is closed in a case where the liquid level in the cooling tank 230 is no longer detected by the liquid level detector 231. That is, the control portion 7 monitors the time from the opening to the closing of the first tank on-off valve 266 as the time required until the discharge of the etching liquid in the cooling tank 230 is completed. Hereinafter, the required time will be referred to as "liquid level drop time".

[0173] As described above, the cooling tank 230 stores the etching liquid discharged from the processing tank 61, and the amount of the etching liquid discharged from the processing tank 61 is substantially the same each time. Therefore, as long as no clogging occurs in the tank discharge pipe 260A, the liquid level lowering time is substantially the same each time.

[0174] Next, the control section 7 determines whether the liquid level lowering time exceeds the threshold value (step S502). In the case where the liquid level lowering time exceeds the threshold value in this determination (step S502, Yes), the control section 7 controls the switching section 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 section 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 on-off valve 266 and opening the second tank on-off valve 267 (step S504).

[0175] Then, the control section 7 performs the cleaning process (step S505). Specifically, the cleaning process in step S505 is, for example, any one of the cleaning processes described in Figures 4-7

[0176] As such, the etching processing apparatus 60A starts the tank cleaning process in the case where the liquid level lowering time exceeds the threshold value, judging that the tank discharge pipe 260A is clogged. Thereby, the cleaning of the cooling tank 230 and the tank discharge pipe 260A can be performed at an appropriate timing.

[0177] Next, the flow of the branch pipe cleaning process in which the branch pipe 213 is cleaned will be described with reference to Figure 11 Figure 11 is a flowchart showing the flow of the branch pipe cleaning process of the second embodiment. In this flowchart, the etching processing apparatus 60A performs the process flow shown in Figure 11

[0178] In addition, at ordinary times where the branch pipe cleaning process is not performed, the outflow 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, the first tank on-off valve 266 is also opened to discharge the liquid from the cooling tank 230 when the liquid level in the cooling tank 230 is detected by the liquid level detector 231 and the liquid temperature detected by the temperature detector 232 is less than the threshold value.

[0179] As described above, the etching processing apparatus 60A according to the second embodiment can perform the cleaning of the cooling tank 230 and the tank discharge pipe 260A at an appropriate timing. Figure 11 ​​​As shown, the control section 7 monitors the time from when the liquid surface in the cooling tank 230 is no longer detected by the liquid surface detection section 231 to when the liquid surface is detected again (step S601). That is, the control section 7 monitors the time required for the liquid surface in the cooling tank 230 to rise due to the liquid being discharged via the branch pipe 213 and for the liquid surface to be detected by the liquid surface detection section 231. Hereinafter, the required time will be referred to as the "liquid surface rise time". The amount of liquid discharged per unit time via the branch pipe 213 is substantially constant. Therefore, as long as no clogging occurs in the branch pipe 213 or the liquid receiving portion discharge pipe 210A, the liquid surface rise time is substantially the same each time.

[0180] Next, the control section 7 determines whether the liquid surface rise time exceeds a threshold value (step S602). In the case where it is determined in this determination that the liquid surface rise time exceeds the threshold value (step S602, Yes), the control section 7 closes the 1st tank opening / closing valve 266 and opens the 2nd tank opening / closing valve 267. Thereby, the control section 7 switches the flow-out destination of the liquid from the cooling tank 230 from the 2nd external discharge pipe 302 to the 3rd external discharge pipe 303 (step S603).

[0181] Then, the control section 7 performs a cleaning process (step S604). The cleaning process in step S604 is, for example, any one of the cleaning processes shown in FIG. 6. Figures 4-7

[0182] As such, the etching processing apparatus 60A starts the branch pipe cleaning process in the case where the liquid surface rise time exceeds the threshold value, judging that the branch pipe 213 or the liquid receiving portion discharge pipe 210A is clogged. Thereby, cleaning of the branch pipe 213 or the liquid receiving portion discharge pipe 210A can be performed at an appropriate timing.

[0183] (3rd Embodiment)

[0184] Next, reference will be made to Figure 3 The structure of the etching processing apparatus of the 12th embodiment will be described. Figure 12 is a view showing the structure of the etching processing apparatus of the 3rd embodiment.

[0185] As shown in FIG. 17, the etching processing apparatus 60B of the 3rd embodiment includes a gas purge section 270. Figure 12

[0186] ​​The gas purging section 270 blows gas into the inside of the liquid receiving section discharge pipe 210. Specifically, the gas purging section 270 includes a gas supply source 271, a first supply pipe 272, a second supply pipe 273, and open / close 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 the like, or an inert gas other than N2 gas. The first supply pipe 272 is connected to the gas supply source 271 at the upstream side. In addition, the end portion of the downstream side of the first supply pipe 272 is disposed in the vicinity of 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 inside of the first liquid receiving section discharge pipe 211.

[0187] The second supply pipe 273 is connected to the gas supply source 271 at the upstream side. In addition, the end portion of the downstream side of the second supply pipe 273 is disposed in the vicinity of the inlet of the second liquid receiving section discharge pipe 212. The second supply pipe 273 blows the gas supplied from the gas supply source 271 into the inside of the second liquid receiving section discharge pipe 212. The open / close valve 275 is provided in the middle of the first supply pipe 272, and opens / closes the first supply pipe 272. In addition, the open / close valve 276 is provided in the middle of the second supply pipe 273, and opens / closes the second supply pipe 273.

[0188] As described above, the etching treatment device 60B blows gas into the inside of the first liquid receiving section discharge pipe 211 and the second liquid receiving section discharge pipe 212 with the gas purging section 270. Thus, it is possible to physically peel off the crystal adhering to the inside of the first liquid receiving section discharge pipe 211 and the second liquid receiving section discharge pipe 212 from the first liquid receiving section discharge pipe 211 and the second liquid receiving section discharge pipe 212.

[0189] Therefore, according to the etching treatment device 60B, it is possible to further suppress the clogging of the liquid discharge line.

[0190] (4th Embodiment)

[0191] Next, the structure of the etching treatment device of the 13th embodiment will be described with reference to Figure 4 The structure of the etching treatment device of the 13th embodiment will be described. Figure 13 is a view showing the structure of the etching treatment device of the 4th embodiment.

[0192] As shown in Figure 13 The etching treatment device 60C of the 4th embodiment further includes an exhaust section 280 that exhausts the inside of the second liquid receiving section 202.

[0193] The exhaust portion 280 includes a suction portion 281 disposed inside the second liquid receiving portion 202 above the treatment tank 61, an exhaust duct 282 connected to the suction portion 281, and a suction device 283 provided to the exhaust duct 282. The exhaust portion 280 sucks the additive mixed with silicon, which is released from the treatment tank 61 as vapor, from the suction portion 281 by suction force generated by the suction device 283, and discharges it to the outside of the second liquid receiving portion 202 via the exhaust duct 282. Thus, the additive mixed with silicon is less likely to adhere to the first liquid receiving portion 201, the second liquid receiving portion 202, and the liquid receiving portion discharge duct 210, so that clogging of the liquid receiving portion discharge duct 210 due to crystallization of the additive mixed with silicon can be suppressed.

[0194] A gas-liquid separation portion 284 that separates vapor flowing through the exhaust duct 282 into gas and liquid is provided to the middle of the exhaust portion 280. The gas-liquid separation portion 284 is connected to the cleaning portion 240 described above, and is supplied with cleaning liquid from the cleaning portion 240. In addition, the gas-liquid separation portion 284 is connected to a liquid discharge duct 285. The liquid discharge duct 285 is connected to the liquid receiving portion discharge duct 210 on the downstream side, and discharges liquid accumulated in the gas-liquid separation portion 284 to the liquid receiving portion discharge duct 210.

[0195] By being thus configured, crystallization of the additive mixed with silicon discharged from the second liquid receiving portion 202 in the exhaust portion 280 to clog the exhaust duct 282 can be suppressed. In addition, by connecting the liquid discharge duct 285 to the liquid receiving portion discharge duct 210, the piping structure can be simplified, for example, as compared with the case where the gas-liquid separation portion 284 is directly connected to the first external discharge duct 301.

[0196] (5th Embodiment)

[0197] In the 5th embodiment, a modification of the cleaning portion will be described with reference to Figure 14 and Figure 15 Figure 14 is a view showing the structure of the cleaning portion of the 4th modification. Figure 15 is a view showing the structure of the cleaning portion of the 5th modification.

[0198] As shown in Figure 14 , the cleaning portion 240D of the 4th modification includes a release portion 251. The release portion 251 is connected to the downstream end portion of the first release duct 250a.

[0199] The release portion 251 is disposed on the upper side of the inclined bottom surface 201a of the first liquid receiving portion 201, in other words, above the side opposite to the side where the first liquid receiving portion discharge duct 211 is provided. By being disposed at the position, DHF or the like can be caused to flow along the bottom surface 201a as an inclined surface, so that the flow rate of DHF or the like can be increased. As such, by increasing the flow rate of DHF or the like, foreign matter adhering to the first liquid receiving portion 201 or the like can be removed more effectively.​

[0200] The release portion 251 includes a plurality of release ports 251a. The plurality of release ports 251a are arranged along the width direction of the inclined bottom surface 201a (a horizontal direction orthogonal to the direction in which the bottom surface 201a extends obliquely, here, the Y-axis direction). As such, by arranging the plurality of release ports 251a along the width direction of the bottom surface 201a, the DHF and the like can be distributed to the first liquid receiving portion 201 without omission.

[0201] As shown in Figure 15 The cleaning portion 240E of the fifth modification example includes a plurality of release portions 252. The plurality of release portions 252 are connected to the downstream side end portion of the first release pipe 250a. Figure 15 In the example shown, the cleaning portion 240E includes two release portions 252. One of the two release portions 252 is arranged on one of the two sides in the width direction of the bottom surface 201a, and the other of the two release portions 252 is arranged on the other of the two sides in the width direction of the bottom surface 201a.

[0202] The release portion 252 includes a plurality of release ports 252a. The plurality of release ports 252a are arranged along the direction in which the bottom surface 201a extends obliquely (a horizontal component of the oblique direction), here, along the X-axis direction. As such, by arranging the plurality of release ports 252a along the oblique direction of the bottom surface 201a as the inclined surface, the first liquid receiving portion 201 can be cleaned more effectively.

[0203] As described above, the substrate processing apparatus (as an example, the etching processing apparatus 60, 60A to 60C) of the embodiment includes a processing tank (as an example, the processing tank 61), a storage portion (as an example, the cooling tank 230), a liquid receiving portion (as an example, the liquid receiving portion 200), a storage portion discharge pipe (as an example, the tank discharge pipe 260), and a liquid receiving portion discharge pipe (as an example, the liquid receiving portion discharge pipe 210). The processing tank can accommodate a plurality of substrates (as an example, the wafer W), and can store a processing liquid (as an example, an etching liquid). The storage portion is connected to the processing tank, and stores the processing liquid discharged from the processing tank. The liquid receiving portion receives the processing liquid spilled from the processing tank. The storage portion discharge pipe discharges the liquid stored in the storage portion. The liquid receiving portion discharge pipe discharges the liquid received by the liquid receiving portion to an external discharge pipe (as an example, the first external discharge pipe 301) provided outside.

[0204] Therefore, according to the substrate processing apparatus of the embodiment, in the batch processing substrate processing apparatus, it is possible to suppress clogging of the liquid discharge line.

[0205] The treatment liquid can contain phosphoric acid and a dissolved silicon-containing compound (as an example, SiO2). In the case where the treatment liquid is stored in a treatment tank, for example, in a boiling state, it is possible that silicon is released from the treatment liquid together with steam, and it is possible that silicon-based crystals adhere to the liquid-receiving portion and the liquid-receiving portion discharge pipe. On the other hand, since such steam mixed with silicon does not enter the storage portion and the storage portion discharge pipe, the storage portion discharge pipe is less likely to be clogged with silicon-based crystals from the treatment liquid than the liquid-receiving portion discharge pipe. Therefore, as shown in the substrate processing apparatus of the embodiment, by separating the liquid discharge path from the liquid-receiving portion including the liquid-receiving portion discharge pipe and the liquid discharge path from the storage portion including the storage portion discharge pipe, it is possible to suppress clogging of the storage portion discharge pipe with silicon-based crystals.

[0206] The substrate processing apparatus of the embodiment can further include a branch pipe (as an example, branch pipe 213), a cleaning portion (as an example, cleaning portion 240), and a switching portion (as an example, switching portion 214). The branch pipe connects a middle portion of the liquid-receiving portion discharge pipe and the storage portion, and discharges liquid flowing in the liquid-receiving portion discharge pipe to the storage portion. The cleaning portion supplies a cleaning liquid for removing crystals from the treatment liquid to the liquid-receiving portion. The switching portion switches a flow-out destination of liquid flowing in the liquid-receiving portion discharge pipe between the external discharge pipe and the storage portion.

[0207] When the temperature of the treatment liquid decreases, a silicon-containing compound (for example, SiO2) dissolved in the treatment liquid can precipitate. Therefore, it is also possible that silicon-based crystals from the treatment liquid adhere to the storage portion and the storage portion discharge pipe. In this regard, according to the substrate processing apparatus of the embodiment, it is possible to clean the storage portion and the storage portion discharge pipe with a cleaning liquid, so it is possible to suppress clogging of not only the liquid-receiving portion discharge pipe but also the storage portion discharge pipe.

[0208] The cleaning liquid can contain a first liquid (as an example, pure water) and a second liquid (as an example, hydrogen fluoride). The cleaning portion includes a first liquid supply pipe (as an example, DIW supply pipe 243), a second liquid supply pipe (as an example, HF supply pipe 244), a release pipe (as an example, first release pipe 250a and second release pipe 250b), a first liquid flow rate adjustment portion (as an example, DIW flow rate adjuster 245), and a second liquid flow rate adjustment portion (as an example, HF flow rate adjuster 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 and the second liquid supply pipes, and supplies the cleaning liquid, the first liquid, or the second liquid to the liquid-receiving portion. The first liquid flow rate adjustment portion is provided to the first liquid supply pipe, and adjusts the flow rate of the first liquid flowing in the first liquid supply pipe. The second liquid flow rate adjustment portion is provided to the second liquid supply pipe, and adjusts the flow rate of the second liquid flowing in the second liquid supply pipe.

[0209] Accordingly, the substrate processing apparatus according to the embodiment can clean the liquid receiving portion, the liquid receiving portion discharge pipe, the storage portion, and the storage portion discharge pipe with the cleaning liquid supplied from the cleaning portion. Therefore, it is possible to further suppress clogging of the liquid discharge line.

[0210] The first liquid can be pure water, and the second liquid can be hydrogen fluoride. The hydrogen fluoride contained in the cleaning liquid, i.e., dilute hydrofluoric acid, can dissolve, for example, silicon-based crystals originating from the processing liquid. Therefore, by supplying the dilute hydrofluoric acid as the cleaning liquid to the liquid receiving portion, it is possible to dissolve silicon-based crystals adhering to the liquid receiving portion and thereby remove them from the liquid receiving portion. Moreover, the cleaning liquid supplied to the liquid receiving portion flows through the liquid receiving portion discharge pipe. Therefore, it is possible to dissolve silicon-based crystals adhering to the liquid receiving portion discharge pipe and thereby remove them.

[0211] The substrate processing apparatus according to the embodiment can further include a liquid level detecting portion (as an example, the liquid level detecting portion 231) that detects a liquid level in the storage portion, and a control portion (as an example, the control portion 7) that controls the cleaning portion and the switching portion. In this case, the control portion can monitor a decrease time of the liquid level in the storage portion based on a detection result of the liquid level detecting portion, and in a case where the decrease time exceeds a threshold value, control the switching portion to switch the outflow destination to the storage portion, and control the cleaning portion to supply the cleaning liquid to the liquid receiving portion. Thereby, it is possible to perform cleaning of the storage portion and the storage portion discharge pipe at an appropriate timing.

[0212] The substrate processing apparatus according to the embodiment can further include a liquid level detecting portion (as an example, the liquid level detecting portion 231) that detects a liquid level in the storage portion, and a control portion (as an example, the control portion 7) that controls the cleaning portion and the switching portion. In this case, the control portion can monitor a rise time of the liquid level in the storage portion based on a detection result of the liquid level detecting portion in a state where the outflow destination is switched to the storage portion, and in a case where the rise time exceeds a threshold value, control the cleaning portion to supply the cleaning liquid to the liquid receiving portion. Thereby, it is possible to perform cleaning of the branch pipe and the liquid receiving portion discharge pipe at an appropriate timing.

[0213] The substrate processing apparatus according to the embodiment can further include a gas purging portion (as an example, the gas purging portion 270) that blows a gas into the inside of the liquid receiving portion discharge pipe. Thereby, it is possible to physically peel off crystals adhering to the inside of the liquid receiving portion discharge pipe. Therefore, it is possible to further suppress clogging of the liquid discharge line.

[0214] The liquid receiving portion can include a first liquid receiving portion (as an example, first liquid receiving portion 201) disposed below the processing tank, and a second liquid receiving portion (as an example, second liquid receiving portion 202) capable of receiving the processing tank and the first liquid receiving portion. In this case, the substrate processing apparatus of the embodiment can further include an exhaust portion (as an example, exhaust portion 280) that exhausts the inside of the second liquid receiving portion. By discharging the silicon mixed vapor released from the processing tank to the outside of the second liquid receiving portion with the exhaust portion, it is possible to further suppress clogging of the liquid receiving portion discharge pipe.

[0215] It should be considered that all points in the embodiments disclosed in the present application are illustrative and are not limited thereto. In fact, the above-described embodiments can be implemented in various embodiments. In addition, the above-described embodiments can be omitted, replaced, and changed in various ways without departing from the scope of the claims and the intent thereof.

Claims

1. A substrate processing apparatus characterized by comprising: The substrate processing apparatus includes: a processing tank capable of housing a plurality of substrates and storing a processing liquid; a storage section connected to the processing tank and storing the processing liquid discharged from the processing tank; a liquid receiving section that receives the processing liquid spilled from the processing tank; a storage section discharge pipe that discharges the liquid stored in the storage section; a liquid receiving section discharge pipe that discharges the liquid received by the liquid receiving section to an external discharge pipe provided outside; a branch pipe that connects a middle portion of the liquid receiving section discharge pipe and the storage section and discharges the liquid flowing in the liquid receiving section discharge pipe to the storage section; a cleaning section that supplies a cleaning liquid for removing a crystal originated from the processing liquid to the liquid receiving section; and a switching section provided at the middle portion of the liquid receiving section discharge pipe and switching a flow-out destination of the liquid flowing in the liquid receiving section discharge pipe between the external discharge pipe and the storage section.

2. The substrate processing apparatus according to claim 1, wherein: the processing liquid contains phosphoric acid and a dissolved silicon-containing compound.

3. The substrate processing apparatus according to claim 1, wherein: the cleaning liquid has a first liquid and a second liquid, the cleaning section includes: a first liquid supply pipe that supplies the first liquid; a second liquid supply pipe that supplies the second liquid; a release pipe that is connected to the first liquid supply pipe and the second liquid supply pipe and releases the cleaning liquid, the first liquid, or the second liquid to the liquid receiving section; a first liquid flow rate adjustment section provided at the first liquid supply pipe and adjusting a flow rate of the first liquid flowing in the first liquid supply pipe; and a second liquid flow rate adjustment section provided at the second liquid supply pipe and adjusting a flow rate of the second liquid flowing in the second liquid supply pipe.

4. The substrate processing apparatus according to claim 3, wherein: the first liquid is pure water, the second liquid is hydrogen fluoride. further comprising:

5. The substrate processing apparatus according to any one of claims 1 to 4, wherein a liquid level detection section that detects a liquid level in the storage section; and a control section that controls the cleaning section and the switching section, the control section monitors a decrease time of the liquid level in the storage section based on a detection result of the liquid level detection section, and in a case where the decrease time exceeds a threshold value, controls the switching section to switch the flow-out destination to the storage section, and controls the cleaning section to supply the cleaning liquid to the liquid receiving section. further comprising: a liquid level detection section that detects a liquid level in the storage section; and 6. The substrate processing apparatus according to any one of claims 1 to 4, wherein a control section that controls the cleaning section and the switching section, the control section monitors a rise time of the liquid level in the storage section based on a detection result of the liquid level detection section in a state where the flow-out destination is switched to the storage section, and in a case where the rise time exceeds a threshold value, controls the cleaning section to supply the cleaning liquid to the liquid receiving section.

7. The substrate processing apparatus according to any one of claims 1 to 4, further comprising: a gas purge section that blows a gas into an inside of the liquid receiving section discharge pipe.

8. The substrate processing apparatus according to any one of claims 1 to 4, wherein: the liquid receiving section includes: a first liquid receiving section disposed below the processing tank; and a second liquid receiving section disposed above the first liquid receiving section. ​ ​ A second liquid receiving portion capable of receiving the processing tank and the first liquid receiving portion, The substrate processing apparatus further includes an exhaust portion that exhausts the inside of the second liquid receiving portion.

9. A method of cleaning the substrate processing apparatus of claim 1, wherein, Comprising: a step of switching the outflow destination from the external drain pipe to the storage portion with the switching portion; and a step of supplying the cleaning liquid from the cleaning portion to the liquid receiving portion after the outflow destination is switched to the storage portion, thereby cleaning the storage portion with the cleaning liquid.

Images