Etching treatment device using phosphoric acid aqueous solution

Abstract

The present invention provides an etching treatment device using a phosphoric acid aqueous solution. The etching treatment device comprises: a treatment tank, which is used to perform etching treatment on a substrate using an etching solution obtained by heating the phosphoric acid aqueous solution; a treatment liquid supply unit, which supplies the phosphoric acid aqueous solution to the treatment tank; a treatment liquid circulation unit, which circulates the etching solution inside the treatment tank; a treatment liquid discharge unit, which discharges the etching solution; and a control unit, which controls the treatment liquid supply unit, the treatment liquid circulation unit, and the treatment liquid discharge unit, wherein the control unit circulates the etching solution using the treatment liquid circulation unit, discharges the etching solution from the treatment liquid discharge unit, and supplies the phosphoric acid aqueous solution from the treatment liquid supply unit to the treatment tank, and the control unit also uses silicon concentration information in the etching solution to perform control so that the silicon concentration of the etching solution in which the substrate is immersed is within a specified concentration range.

Description

[0001] The present application is a divisional application of an application filed on January 29, 2016, with application number 201610065467.3 and invention name “Substrate Liquid Treatment Device and Substrate Liquid Treatment Method”. Technical Field

[0002] The present invention relates to an etching processing device using a phosphoric acid aqueous solution. Background Art

[0003] In the manufacturing process of semiconductor components, flat panel displays, etc., a substrate liquid processing apparatus is used. The substrate liquid processing apparatus performs an etching process on a substrate such as a semiconductor wafer or a liquid crystal substrate using an etching liquid (processing liquid).

[0004] Conventional substrate liquid processing apparatuses include: a processing liquid storage unit that stores processing liquid for processing a substrate; a processing liquid supply unit that supplies processing liquid to the processing liquid storage unit; and a processing liquid circulation unit that circulates the processing liquid stored in the processing liquid storage unit and heats the processing liquid, etc.

[0005] The substrate liquid processing device immerses a plurality of substrates in the processing liquid stored in the processing liquid storage unit and performs liquid processing on the substrates using the processing liquid. In addition, the substrate liquid processing device circulates the processing liquid supplied from the processing liquid supply unit through the processing liquid circulation unit and heats the processing liquid to a predetermined temperature.

[0006] In the substrate liquid treatment device, when the substrate is repeatedly treated with the treatment liquid, the concentration of impurities contained in the treatment liquid increases due to the treatment of the substrate, so that the substrate cannot be treated well. For example, when a phosphoric acid aqueous solution (etching liquid) is used to etch the substrate, since the ability (etching rate) of the treatment liquid depends on the silicon concentration in the treatment liquid, it is necessary to keep the silicon concentration in the treatment liquid within a fixed range. However, the silicon concentration in the etching liquid increases due to repeated treatment of the substrate, and the ability of the treatment liquid decreases, so that the substrate cannot be etched well (for example, refer to Patent Document 1).

[0007] Therefore, in conventional substrate liquid processing apparatuses, concentration sensors for measuring the silicon concentration in the processing liquid are provided in the processing liquid storage unit and the processing liquid circulation unit.

[0008] Patent Document 1: Japanese Patent Application Publication No. 2001-23952 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] Furthermore, in the above-mentioned conventional substrate liquid processing apparatus, the concentration sensor is provided in the processing liquid storage section or the processing liquid circulation section, and therefore the processing liquid is always in contact with the concentration sensor.

[0011] Therefore, in the conventional substrate liquid processing apparatus, there is a possibility that the concentration sensor may be corroded by the processing liquid or that impurities contained in the processing liquid may adhere to the concentration sensor, causing the concentration sensor to fail or malfunction.

[0012] Furthermore, in conventional substrate liquid processing apparatuses, dust or the like precipitated from a concentration sensor is mixed into the processing liquid, and particles are attached to the substrate when the substrate is processed using the processing liquid, which may result in failure to properly perform liquid processing on the substrate.

[0013] Solutions for solving problems

[0014] Therefore, in the present invention, the substrate liquid processing device comprises: a processing liquid storage section, which stores processing liquid for processing a substrate; a processing liquid supply section, which supplies the processing liquid to the processing liquid storage section; a processing liquid circulation section, which circulates the processing liquid inside the processing liquid storage section; a processing liquid discharge section, which discharges the processing liquid from the processing liquid circulation section; a concentration sensor, which is arranged in the processing liquid discharge section, and measures the concentration of the substrate processing product in the processing liquid; and a control section, which controls the processing liquid supply section, wherein the control section circulates the processing liquid through the processing liquid circulation section, so that the circulated processing liquid is discharged from the processing liquid discharge section intermittently at a specified timing or continuously within a specified time, and supplies new processing liquid from the processing liquid supply section, and measures the concentration of the substrate processing product in the processing liquid at a specified timing through the concentration sensor for the discharged processing liquid.

[0015] In addition, the concentration sensor is provided in a bypass flow path formed in the processing liquid discharge portion.

[0016] In addition, the concentration sensor measures the concentration of the substrate processing product in the processing liquid when the substrate is processed by the processing liquid.

[0017] Furthermore, the frequency of the predetermined timing at which the concentration of the substrate processing product in the processing liquid is measured by the concentration sensor is smaller than the frequency of the predetermined timing at which the processing liquid is discharged from the processing liquid discharge portion.

[0018] In addition, a silicon wafer is used as the substrate, and the concentration sensor measures the concentration of silicon in the processing liquid.

[0019] In addition, in the present invention, in the substrate liquid processing method, the processing liquid stored in the processing liquid storage section for processing the substrate is circulated through the processing liquid circulation section, and the circulated processing liquid is intermittently discharged at a specified timing or continuously within a specified time from a processing liquid discharge section branched off in the middle of the processing liquid circulation section, and new processing liquid is supplied from the processing liquid supply section, and with respect to the discharged processing liquid, the concentration of the substrate processing product in the processing liquid is measured at a specified timing by a concentration sensor provided in the processing liquid discharge section.

[0020] Furthermore, the processing liquid discharged from the processing liquid discharge portion flows into a bypass flow path formed by branching in the middle of the processing liquid discharge portion, and the concentration of the substrate processing product in the processing liquid is measured by the concentration sensor provided in the bypass flow path.

[0021] In addition, the concentration sensor measures the concentration of the substrate processing product in the processing liquid when the substrate is processed by the processing liquid.

[0022] In addition, in the present invention, a computer-readable storage medium is provided, which stores a substrate liquid processing program for performing liquid processing of the substrate using a substrate liquid processing device, and the substrate liquid processing device has: a processing liquid storage part, which stores a processing liquid for processing the substrate; a processing liquid supply part, which supplies the processing liquid to the processing liquid storage part; a processing liquid circulation part, which circulates the processing liquid inside the processing liquid storage part; a processing liquid discharge part, which draws out from the processing liquid circulation part and discharges the processing liquid; and a concentration sensor, which is arranged in the processing liquid discharge part, and measures the concentration of the substrate processing product in the processing liquid. In the computer-readable storage medium, the processing liquid is circulated by the processing liquid circulation part, and the circulated processing liquid is discharged from the processing liquid discharge part intermittently at a specified timing or continuously within a specified time, and new processing liquid is supplied from the processing liquid supply part. For the discharged processing liquid, the concentration of the substrate processing product in the processing liquid is measured at a specified timing by the concentration sensor.

[0023] Effects of the Invention

[0024] In the present invention, it is possible to prevent the concentration sensor from malfunctioning or malfunctioning and to perform liquid processing on the substrate in a satisfactory manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an explanatory diagram showing a plan view of a substrate liquid processing apparatus.

[0026] Figure 2 It is an explanatory diagram showing an etching processing apparatus.

[0027] Figure 3 It is an explanatory diagram showing a processing liquid discharge unit.

[0028] Figure 4 It is an explanatory diagram showing a substrate liquid processing method.

[0029] Figure 5 It is an explanatory diagram showing a substrate liquid processing method.

[0030] Description of Reference Numerals

[0031] 1: substrate liquid processing device; 7: control unit; 8: substrate; 38: processing liquid storage unit; 39: processing liquid supply unit; 40: processing liquid circulation unit; 41: processing liquid discharge unit; 61: concentration sensor. DETAILED DESCRIPTION

[0032] Hereinafter, the specific structures of the substrate liquid processing apparatus, substrate liquid processing method and substrate liquid processing program according to the present invention will be described with reference to the accompanying drawings.

[0033] like Figure 1 As shown, the substrate liquid processing apparatus 1 includes a carrier loading and unloading unit 2 , a substrate group forming unit 3 , a substrate group placing unit 4 , a substrate group conveying unit 5 , a substrate group processing unit 6 , and a control unit 7 .

[0034] The carrier loading / unloading unit 2 loads and unloads a carrier 9 that accommodates a plurality of (eg, 25) substrates (silicon wafers) 8 arranged vertically in a horizontal posture.

[0035] The carrier loading and unloading section 2 is provided with a carrier stage 10 for loading a plurality of carriers 9, a carrier conveying mechanism 11 for conveying the carriers 9, carrier holders 12 and 13 for temporarily storing the carriers 9, and a carrier placing table 14 for placing the carriers 9. Here, the carrier holder 12 temporarily stores the substrate 8 as a product before the substrate group processing section 6 processes the substrate 8. In addition, the carrier holder 13 temporarily stores the substrate 8 as a product after the substrate group processing section 6 processes the substrate 8.

[0036] The carrier loading / unloading unit 2 uses the carrier conveying mechanism 11 to convey the carrier 9 loaded from the outside to the carrier stage 10 to the carrier holder 12 and the carrier mounting table 14. The carrier loading / unloading unit 2 uses the carrier conveying mechanism 11 to convey the carrier 9 mounted on the carrier mounting table 14 to the carrier holder 13 and the carrier stage 10. The carrier 9 loaded to the carrier stage 10 is unloaded to the outside.

[0037] The substrate group forming unit 3 combines the substrates 8 accommodated in one or more carriers 9 to form a substrate group consisting of a plurality of (eg, 50) substrates 8 to be processed simultaneously.

[0038] The substrate group forming unit 3 is provided with a substrate conveying mechanism 15 for conveying a plurality of substrates 8. The substrate conveying mechanism 15 can change the posture of the substrate 8 from a horizontal posture to a vertical posture or from a vertical posture to a horizontal posture during conveyance of the substrate 8.

[0039] The substrate group forming section 3 uses the substrate conveying mechanism 15 to convey the substrate 8 from the carrier 9 mounted on the carrier mounting table 14 to the substrate group mounting section 4, and forms a substrate group in the substrate group mounting section 4. In addition, the substrate group forming section 3 uses the substrate conveying mechanism 15 to convey the substrate group mounted on the substrate group mounting section 4 to the carrier 9 mounted on the carrier mounting table 14. In addition, the substrate conveying mechanism 15 has two types of substrate supporting sections, namely, a pre-processing substrate supporting section for supporting the substrate 8 before processing (before being conveyed by the substrate group conveying section 5) and a post-processing substrate supporting section for supporting the substrate 8 after processing (after being conveyed by the substrate group conveying section 5), as substrate supporting sections for supporting a plurality of substrates 8. Thus, particles and the like attached to the substrate 8 and the like before processing are prevented from being transferred to the substrate 8 and the like after processing.

[0040] The substrate group placement section 4 temporarily places (stands by) the substrate group conveyed between the substrate group forming section 3 and the substrate group processing section 6 by the substrate group conveying section 5 via the substrate group placing table 16 .

[0041] The substrate group placement section 4 is provided with a loading-side substrate group placement table 17 for placing the substrate group before the loading process (before being transported by the substrate group transport section 5) and a discharge-side substrate group placement table 18 for placing the substrate group after the loading process (after being transported by the substrate group transport section 5). A plurality of substrates 8 of one substrate group are placed on the loading-side substrate group placement table 17 and the discharge-side substrate group placement table 18 in a vertical position in a front-to-back arrangement.

[0042] In the substrate group placement section 4, the substrate group formed by the substrate group forming section 3 is placed on the carry-in side substrate group placement table 17, and the substrate group is carried into the substrate group processing section 6 by the substrate group conveying section 5. In addition, in the substrate group placement section 4, the substrate group carried out from the substrate group processing section 6 by the substrate group conveying section 5 is placed on the carry-out side substrate group placement table 18, and the substrate group is conveyed to the substrate group forming section 3.

[0043] The substrate group transporting section 5 transports the substrate group between the substrate group placing section 4 and the substrate group processing section 6 and inside the substrate group processing section 6 .

[0044] The substrate group conveying unit 5 is provided with a substrate group conveying mechanism 19 for conveying the substrate group. The substrate group conveying mechanism 19 includes a guide rail 20 arranged along the substrate group placing unit 4 and the substrate group processing unit 6, and a moving body 21 that moves along the guide rail 20 while holding a plurality of substrates 8. A substrate holding body 22 that holds a plurality of substrates 8 arranged front and back in a vertical posture is freely provided on the moving body 21 so as to be able to move forward and backward.

[0045] The substrate group conveying unit 5 receives the substrate group placed on the loading-side substrate group placement table 17 through the substrate holding body 22 of the substrate group conveying mechanism 19, and transfers the substrate group to the substrate group processing unit 6. In addition, the substrate group conveying unit 5 receives the substrate group processed by the substrate group processing unit 6 through the substrate holding body 22 of the substrate group conveying mechanism 19, and transfers the substrate group to the unloading-side substrate group placement table 18. The substrate group conveying unit 5 conveys the substrate group inside the substrate group processing unit 6 using the substrate group conveying mechanism 19.

[0046] The substrate group processing section 6 treats a plurality of substrates 8 arranged in a vertical posture in a front-to-back manner as one substrate group and performs processing such as etching, cleaning, and drying.

[0047] In the substrate group processing section 6, a drying processing device 23 for drying the substrate 8, a substrate holder cleaning processing device 24 for cleaning the substrate holder 22, a cleaning processing device 25 for cleaning the substrate 8, and two etching processing devices 26 for etching the substrate 8 are arranged side by side.

[0048] In the drying processing device 23, a substrate lifting mechanism 28 is provided in the processing tank 27 so as to be able to be raised and lowered freely. A drying processing gas (IPA (isopropyl alcohol) or the like) is supplied to the processing tank 27. A plurality of substrates 8 of one substrate group are held in a vertical position in a front-to-back arrangement by the substrate lifting mechanism 28. The drying processing device 23 receives the substrate group from the substrate holding body 22 of the substrate group conveying mechanism 19 through the substrate lifting mechanism 28, and lifts the substrate group through the substrate lifting mechanism 28, thereby performing drying processing on the substrate 8 using the drying processing gas supplied to the processing tank 27. In addition, the drying processing device 23 transfers the substrate group from the substrate lifting mechanism 28 to the substrate holding body 22 of the substrate group conveying mechanism 19.

[0049] The substrate holder cleaning processing device 24 can supply a cleaning processing liquid and a dry gas to the processing tank 29 , and after supplying the cleaning processing liquid to the substrate holder 22 of the substrate group conveying mechanism 19 , supply the dry gas to clean the substrate holder 22 .

[0050] The cleaning device 25 includes a cleaning tank 30 and a rinsing tank 31. Substrate lifting mechanisms 32 and 33 are provided in the tanks 30 and 31 so as to be freely movable. A cleaning solution (SC-1 or the like) is stored in the cleaning tank 30. A rinsing solution (pure water or the like) is stored in the rinsing tank 31.

[0051] The etching device 26 includes an etching tank 34 and a rinsing tank 35. Substrate lifting mechanisms 36 and 37 are freely provided in the respective tanks 34 and 35. The etching tank 34 stores an etching solution (aqueous phosphoric acid solution). The rinsing tank 35 stores a rinsing solution (pure water, etc.).

[0052] These cleaning processing apparatus 25 and etching processing apparatus 26 have the same structure. The etching processing apparatus 26 is described. A plurality of substrates 8 of one substrate group are held in a vertical posture in a front-to-back arrangement by substrate lifting mechanisms 36 and 37. The etching processing apparatus 26 receives the substrate group from the substrate holding body 22 of the substrate group conveying mechanism 19 by the substrate lifting mechanism 36, and lifts and lowers the substrate group by the substrate lifting mechanism 36, thereby immersing the substrate group in the etching processing liquid in the processing tank 34 to perform etching processing on the substrate 8. Thereafter, the etching processing apparatus 26 transfers the substrate group from the substrate lifting mechanism 36 to the substrate holding body 22 of the substrate group conveying mechanism 19. In addition, the etching processing apparatus 26 receives the substrate group from the substrate holding body 22 of the substrate group conveying mechanism 19 by the substrate lifting mechanism 37, and lifts and lowers the substrate group by the substrate lifting mechanism 37, thereby immersing the substrate group in the rinsing processing liquid in the processing tank 35 to perform rinsing processing on the substrate 8. Thereafter, the etching processing device 26 transfers the substrate group from the substrate lifting mechanism 37 to the substrate holding body 22 of the substrate group conveying mechanism 19 .

[0053] In the etching processing apparatus 26 , an aqueous solution of a chemical (phosphoric acid) having a predetermined concentration (a phosphoric acid aqueous solution of 88.3 wt %) is used as a processing liquid (etching liquid) to perform liquid processing (etching processing) on ​​the substrate 8 .

[0054] like Figure 2 As shown, the etching processing device 26 has: a processing liquid storage section 38, which is used to store a processing liquid composed of a phosphoric acid aqueous solution of a specified concentration (88.3 weight % phosphoric acid aqueous solution) and to process the substrate 8; a processing liquid supply section 39, which is used to supply the processing liquid to the processing liquid storage section 38; a processing liquid circulation section 40, which is used to circulate the processing liquid stored in the processing liquid storage section 38; and a processing liquid discharge section 41, which is used to discharge the processing liquid from the processing liquid storage section 38.

[0055] In the processing liquid storage part 38, an outer tank 42 with an open top is formed around the upper part of the processing tank 34 with an open top, and the processing liquid is stored in the processing tank 34 and the outer tank 42. The processing liquid is stored in the processing tank 34, and the substrate 8 is immersed in the processing liquid by the substrate lifting mechanism 36 to perform liquid processing on the substrate 8. The processing liquid overflowing from the processing tank 34 is stored in the outer tank 42, and the processing liquid is supplied to the processing tank 34 by the processing liquid circulation part 40.

[0056] The treatment liquid supply part 39 includes an aqueous solution supply part 43 and a water supply part 44. The aqueous solution supply part 43 is used to supply an aqueous solution (85 weight % phosphoric acid aqueous solution) of a reagent (phosphoric acid) having a concentration different from the concentration of the treatment liquid (lower than the concentration of the treatment liquid) to the treatment liquid storage part 38, and the water supply part 44 is used to supply water (pure water) to the treatment liquid storage part 38.

[0057] The aqueous solution supply unit 43 connects an aqueous solution supply source 45 for supplying a phosphoric acid aqueous solution of a predetermined concentration (85 wt%) and a predetermined temperature (25° C.) to the outer tank 42 of the treatment liquid storage unit 38 via a flow regulator 46. The flow regulator 46 is connected to the control unit 7, and the control unit 7 performs opening and closing control and flow control on the flow regulator 46.

[0058] The water supply unit 44 connects a water supply source 47 for supplying pure water at a predetermined temperature (25°C) to the outer tank 42 of the treatment liquid storage unit 38 via a flow regulator 48. The flow regulator 48 is connected to the control unit 7, which controls the opening and closing of the flow regulator 48 and the flow rate.

[0059] The treatment liquid circulation unit 40 forms a circulation flow path 49 between the bottom of the outer tank 42 of the treatment liquid storage unit 38 and the bottom of the treatment tank 34. A pump 50, a heater 51 and a filter 52 are sequentially arranged in the circulation flow path 49. The pump 50 and the heater 51 are connected to the control unit 7, and the control unit 7 drives and controls the pump 50 and the heater 51. In addition, the treatment liquid circulation unit 40 circulates the treatment liquid from the outer tank 42 to the treatment tank 34 by driving the pump 50. At this time, the treatment liquid is heated to a specified temperature (165°C) by the heater 51.

[0060] The treatment liquid discharge portion 41 includes a first treatment liquid discharge portion 53 that discharges the treatment liquid from the treatment liquid storage portion 38 and a second treatment liquid discharge portion 54 that discharges the treatment liquid from the treatment liquid circulation portion 40 .

[0061] The first treatment liquid discharge unit 53 connects a discharge flow path 55 connected to an external discharge pipe to the bottom of the treatment tank 34 of the treatment liquid storage unit 38, and an on-off valve 56 is provided in the discharge flow path 55. The on-off valve 56 is connected to the control unit 7, and the control unit 7 controls the on-off of the on-off valve 56.

[0062] The second process liquid discharge section 54 connects a discharge flow path 57 connected to an external discharge pipe with a midway portion of the circulation flow path 49 of the process liquid circulation section 40 (between the heater 51 and the filter 52), and an on-off valve 58 is provided in the discharge flow path 57. In addition, the second process liquid discharge section 54 connects a bypass flow path 59 connected to an external discharge pipe with a midway portion of the discharge flow path 57 (downstream of the on-off valve 58), and an on-off valve 60 and a concentration sensor 61 for measuring the silicon concentration in the process liquid are provided in sequence in the bypass flow path 59. The on-off valves 58 and 60 are connected to the control section 7, and the control section 7 controls the opening and closing of the on-off valves 58 and 60. The concentration sensor 61 is connected to the control section 7, and measures the silicon concentration in the process liquid under the control of the control section 7.

[0063] In this way, in the substrate liquid processing apparatus 1, the concentration sensor 61 is provided in the second processing liquid discharge section 54 branched from the processing liquid circulation section 40, so that the processing liquid contacts the concentration sensor 61 only when the processing liquid is discharged from the processing liquid circulation section 40. As a result, in the substrate liquid processing apparatus 1, it is possible to prevent the concentration sensor 61 from being corroded by the processing liquid, or the concentration sensor 61 from malfunctioning or malfunctioning due to impurities contained in the processing liquid adhering to the concentration sensor 61. In addition, in the substrate liquid processing apparatus 1, it is possible to prevent dust precipitated from the concentration sensor 61 from mixing with the processing liquid and particles from adhering to the substrate 8, thereby preventing the substrate 8 from being properly processed by liquid.

[0064] Here, the concentration sensor 61 is not limited to Figure 2 and Figure 3 In the case where the bypass flow path 59 is provided as shown in (a) of FIG. 1 , it is also possible to Figure 3 As shown in (b) of FIG. 1 , the bypass flow path 62 branched from the circulation flow path 49 may be provided. Figure 3 62) is disposed in the discharge flow path 57. When the concentration sensor 61 is disposed in the discharge flow path 57, only a portion of the treatment liquid stored in the treatment liquid storage section 38 (the treatment liquid discharged from the treatment liquid circulation section 40) contacts the concentration sensor 61. When the concentration sensor 61 is disposed in the bypass flow paths 59 and 62, only a portion of the treatment liquid further discharged from the treatment liquid circulation section 40 (the treatment liquid discharged from the bypass flow paths 59 and 62) contacts the concentration sensor 61. Therefore, by disposing the concentration sensor 61 in the bypass flow paths 59 and 62, the time (frequency) during which the treatment liquid contacts the concentration sensor 61 can be further shortened (reduced).

[0065] The etching treatment device 26 supplies a phosphoric acid aqueous solution of a predetermined concentration (85 wt%) and a predetermined temperature (25° C.) to the treatment liquid storage portion 38 through the aqueous solution supply portion 43, heats the supplied phosphoric acid aqueous solution to a predetermined concentration (88.3 wt%) and a predetermined temperature (165° C.) through the treatment liquid circulation portion 40 to generate a treatment liquid, and stores the treatment liquid in the treatment liquid storage portion 38. In addition, the etching treatment device 26 supplies an amount of pure water corresponding to the amount of water evaporated by heating to the treatment liquid storage portion 38 through the water supply portion 44. Thus, the etching treatment device 26 stores the treatment liquid of a predetermined concentration (88.3 wt%) and a predetermined temperature (165° C.) in the treatment tank 34 of the treatment liquid storage portion 38, immerses the substrate 8 in the treatment liquid through the substrate lifting mechanism 36, and performs etching treatment on the substrate 8.

[0066] In addition, the etching processing device 26 discharges a portion (or all) of the processing liquid in the processing liquid storage section 38 through the processing liquid discharge section 41, and supplies new processing liquid (aqueous solution and / or pure water) through the processing liquid supply section 39, thereby appropriately updating (replacing) the processing liquid stored in the processing liquid storage section 38.

[0067] The control unit 7 controls the operation of each unit of the substrate liquid processing apparatus 1 (the carrier loading and unloading unit 2 , the substrate group forming unit 3 , the substrate group placing unit 4 , the substrate group conveying unit 5 , the substrate group processing unit 6 , etc.).

[0068] The control unit 7 is, for example, a computer and has a computer-readable storage medium 63. The storage medium 63 stores a program for controlling various processes performed in the substrate liquid processing apparatus 1. The control unit 7 reads and executes the program stored in the storage medium 63, thereby controlling the operation of the substrate liquid processing apparatus 1. In addition, the program may be a program stored in the computer-readable storage medium 63 or a program installed from other storage media to the storage medium 63 of the control unit 7. Examples of the computer-readable storage medium 63 include a hard disk (HD), a floppy disk (FD), a compact disk (CD), a magneto-optical disk (MO), a memory card, and the like.

[0069] The substrate liquid processing apparatus 1 is constructed as described above, and the operation of each part (the carrier loading and unloading part 2, the substrate group forming part 3, the substrate group placing part 4, the substrate group conveying part 5, the substrate group processing part 6, etc.) is controlled by the control part 7, thereby processing the substrate 8.

[0070] When the substrate 8 is etched by the substrate liquid processing apparatus 1, the etching processing apparatus 26 and the like are controlled by the control unit 7 as described below according to the substrate liquid processing program stored in the storage medium 63 (see Figure 4 ).

[0071] First, the substrate liquid processing apparatus 1 replaces the processing liquid stored in the processing liquid storage portion 38 before starting the etching process on the substrate 8 (processing liquid replacement step).

[0072] In the process liquid replacement process, the control unit 7 supplies the process liquid to the process liquid storage unit 38 through the process liquid supply unit 39, and circulates the process liquid while heating the process liquid through the process liquid circulation unit 40, thereby generating a process liquid of a specified concentration (88.3 weight %) and a specified temperature (165°C). Afterwards, the control unit 7 immerses the sample silicon wafer in the process liquid for a specified time through the substrate lifting mechanism 36 to make the silicon concentration in the process liquid become a specified concentration. In the process liquid replacement process, the control unit 7 circulates the process liquid through the process liquid circulation unit 40, opens the on-off valve 58 at a specified timing to discharge the process liquid from the process liquid circulation unit 40 through the second process liquid discharge unit 54. Then, the control unit 7 opens the on-off valve 60 at a specified timing (for example, before the process liquid replacement process is about to end) and measures the silicon concentration in the process liquid through the concentration sensor 61. When the silicon concentration measured by the concentration sensor 61 is not within the specified concentration range, the control unit 7 issues an alarm and interrupts the process. Furthermore, in the process of replacing the processing liquid, the processing liquid can be circulated all the time by the processing liquid circulation unit 40, or the processing liquid can be circulated intermittently by the processing liquid circulation unit 40. In addition, for example, the sample silicon wafer can be immersed in the processing liquid for a specified time, and after the silicon wafer is immersed in the processing liquid, the circulation can be temporarily stopped immediately, and the circulation can be performed from the specified timing.

[0073] Here, the relationship between the immersion time of the silicon wafer and the silicon concentration is investigated in advance, and the silicon concentration is brought into a predetermined concentration range by immersing the sample silicon wafer in the processing liquid for a predetermined time. However, the following control may be performed: the concentration sensor 61 measures the silicon concentration at a predetermined timing, and the sample silicon wafer is immersed in the processing liquid until the silicon concentration reaches the predetermined concentration range. In addition, when the frequency of the timing of opening the on-off valve 60 and measuring by the concentration sensor 61 is less than the frequency of the timing of opening the on-off valve 58 and discharging the processing liquid, the time (frequency) of the processing liquid contacting the concentration sensor 61 can be further shortened (reduced).

[0074] After the silicon concentration measured by the concentration sensor 61 falls within a predetermined concentration range, the substrate liquid processing apparatus 1 performs an etching process on the substrate 8 (substrate liquid processing step).

[0075] In the substrate liquid processing step, a substrate loading step of loading the substrate 8 into the processing tank 34 , a substrate processing step of processing the substrate 8 in the processing tank 34 , and a substrate unloading step of unloading the substrate 8 from the processing tank 34 are performed.

[0076] In the substrate carrying-in process, after the substrate lifting mechanism 36 is raised from the inside of the processing tank 34, the substrate 8 of one substrate group to be processed simultaneously is transported from the substrate group transport mechanism 19 to the substrate lifting mechanism 36, and then the substrate lifting mechanism 36 holding the substrate 8 is lowered into the inside of the processing tank 34. Thus, the substrate 8 is immersed in the processing liquid stored in the processing tank 34.

[0077] In the substrate processing step, the substrate lifting mechanism 36 is kept in a lowered state for a predetermined time in the processing tank 34. Thus, the substrate 8 is immersed in the processing liquid for a predetermined time to perform etching processing on the substrate 8.

[0078] In the substrate unloading step, after the substrate lifting mechanism 36 holding the substrate 8 is raised from the inside of the processing tank 34 , the substrates 8 of one substrate group to be processed simultaneously are transported from the substrate lifting mechanism 36 to the substrate group transport mechanism 19 .

[0079] In the substrate liquid treatment process, when the substrate 8 is etched by the treatment liquid, the concentration of silicon contained in the treatment liquid gradually increases. Since the capacity (etching rate) of the treatment liquid depends on the silicon concentration in the treatment liquid, it is necessary to keep the silicon concentration in the treatment liquid within a fixed concentration range. Therefore, the control unit 7 drives the pump 50 to circulate the treatment liquid through the treatment liquid circulation unit 40 during the etching process of the substrate 8, and intermittently opens the on-off valve 58 from a specified timing, so that a part of the treatment liquid is discharged from the treatment liquid circulation unit 40 via the second treatment liquid discharge unit 54, and new treatment liquid is supplied from the treatment liquid supply unit 39. Then, the control unit 7 opens the on-off valve 60 at a specified timing (for example, immediately after the substrate liquid treatment process starts and before the substrate liquid treatment process is about to end) to measure the silicon concentration in the treatment liquid through the concentration sensor 61. When the silicon concentration measured by the concentration sensor 61 is not within the specified concentration range, the control unit 7 issues an alarm and interrupts the process. In addition, in the substrate liquid processing step, the processing liquid may be intermittently circulated by the processing liquid circulation unit 40 , or the processing liquid may be always circulated by the processing liquid circulation unit 40 .

[0080] Here, the relationship between the etching time of the substrate 8, the discharge amount of the processing liquid during the etching process, the supply amount of the new processing liquid, and the silicon concentration is investigated in advance, and the silicon concentration is made to fall within the specified concentration range by discharging a specified amount of the processing liquid during the etching process of the substrate 8 and newly supplying a specified amount of the processing liquid. However, the following control can also be performed: the concentration sensor 61 measures the silicon concentration at a specified timing, and when the silicon concentration is above the specified concentration, the substrate liquid processing step is terminated. In addition, here, when the frequency of the timing of opening the on-off valve 60 and measuring with the concentration sensor 61 is less than the frequency of the timing of opening the on-off valve 58 to discharge the processing liquid, the time (frequency) of the processing liquid contacting the concentration sensor 61 can be further shortened (reduced).

[0081] After the substrate liquid processing apparatus 1 repeats the substrate loading step, the substrate processing step, and the substrate unloading step a predetermined number of times, it adjusts the silicon concentration of the processing liquid so that it falls within a predetermined range (adjustment step).

[0082] In the adjustment process, the control unit 7 supplies the treatment liquid to the treatment liquid storage unit 38 through the treatment liquid supply unit 39, and circulates the treatment liquid through the treatment liquid circulation unit 40 while heating the treatment liquid, thereby generating a treatment liquid of a specified concentration (88.3 weight %) and a specified temperature (165° C.), and adjusting the silicon concentration in the treatment liquid to a specified concentration. In the adjustment process, the control unit 7 circulates the treatment liquid through the treatment liquid circulation unit 40, intermittently opens the on-off valve 58 from a specified timing to discharge the treatment liquid from the treatment liquid circulation unit 40 through the second treatment liquid discharge unit 54, and supplies new treatment liquid from the treatment liquid supply unit 39. Then, the control unit 7 opens the on-off valve 60 at a specified timing (for example, before the adjustment process is about to end) and measures the silicon concentration in the treatment liquid through the concentration sensor 61. When the silicon concentration measured by the concentration sensor 61 is not within the specified concentration range, the control unit 7 issues an alarm and interrupts the transfer of the substrate 8 into the treatment tank 34. Furthermore, in the adjustment process, the processing liquid may be circulated continuously by the processing liquid circulation unit 40, or may be circulated intermittently by the processing liquid circulation unit 40, or may be temporarily stopped from circulating and circulated from a specified timing.

[0083] Here, the relationship between the discharge amount of the treatment liquid, the supply amount of the new treatment liquid, and the silicon concentration is investigated in advance, and the silicon concentration is brought into the prescribed concentration range by discharging a prescribed amount of the treatment liquid and newly supplying a prescribed amount of the treatment liquid. However, the following control may be performed: the concentration sensor 61 measures the silicon concentration at a prescribed timing, and the treatment liquid is discharged and a new treatment liquid is supplied until the silicon concentration reaches the prescribed concentration range. In addition, when the frequency of the timing of opening the on-off valve 60 and measuring by the concentration sensor 61 is less than the frequency of the timing of opening the on-off valve 58 to discharge the treatment liquid, the time (frequency) of the treatment liquid contacting the concentration sensor 61 can be further shortened (reduced).

[0084] As described above, in the above-mentioned substrate liquid processing device 1, the processing liquid stored in the processing liquid storage section 38 for processing the substrate 8 is circulated through the processing liquid circulation section 40, and the circulated processing liquid is discharged from the second processing liquid discharge section 54 branched off in the middle of the processing liquid circulation section 40, and the silicon concentration in the discharged processing liquid is measured by the concentration sensor 61 arranged in the second processing liquid discharge section 54.

[0085] Therefore, in the above-mentioned substrate liquid processing device 1, the time that the concentration sensor 61 contacts the processing liquid can be shortened, the concentration sensor 61 can be prevented from malfunctioning or malfunctioning, etc., and the dust precipitated from the concentration sensor 61 can be prevented from becoming particles and adhering to the substrate 8, so that the liquid processing of the substrate 8 can be performed well.

[0086] In addition, as another embodiment, Figure 4 In the embodiment shown in the figure, in order to keep the silicon concentration in the processing liquid within a fixed concentration range in the substrate liquid processing step and the adjustment step, the control unit 7 drives the pump 50 to circulate the processing liquid through the processing liquid circulation unit 40 during the etching process of the substrate 8, intermittently opens the on-off valve 58 from a predetermined timing to discharge a part of the processing liquid from the processing liquid circulation unit 40 through the second processing liquid discharge unit 54, and supplies new processing liquid from the processing liquid supply unit 39, but is not limited to this, and may also be as follows Figure 5 As shown, the on-off valve 58 is opened continuously for a predetermined time from a predetermined timing to discharge a part of the processing liquid from the processing liquid circulation unit 40 through the second processing liquid discharge unit 54 , and new processing liquid is supplied from the processing liquid supply unit 39 .

[0087] In addition, in the substrate liquid treatment process, it can be set that the treatment liquid is continuously discharged and supplied from the start of the substrate liquid treatment process, for example, until the middle of the process, and the treatment liquid is neither discharged nor supplied thereafter. In addition, it can be set that the treatment liquid is neither discharged nor supplied from the start of the substrate liquid treatment process, for example, until the middle of the treatment, and the treatment liquid is continuously discharged and supplied from the middle to the end.

[0088] In addition, as another embodiment, the timing for opening the on-off valve 60 and measuring through the concentration sensor 61 is set to a specified timing within the period during which the on-off valve 58 is opened to discharge the processing liquid (for example, immediately after the start of the substrate liquid processing process and before the end of the substrate liquid processing process), thereby further shortening (reducing) the time (frequency) that the processing liquid contacts the concentration sensor 61.

[0089] In addition, as another embodiment, for example, based on the value obtained by multiple measurements of the silicon concentration in the discharged processing liquid by the concentration sensor 61 arranged in the second processing liquid discharge part 54, in the substrate liquid processing step, the rising rate of the silicon concentration is calculated based on the multiple measurement values, and when it is judged that the silicon concentration exceeds the prescribed concentration range during the processing of the substrate 8, the discharge amount of the discharged processing liquid and the supply amount of the new processing liquid are corrected in such a way that the silicon concentration does not exceed the prescribed concentration range.

[0090] In addition, as another embodiment, in order to further shorten (reduce) the time (frequency) that the treatment liquid contacts the concentration sensor 61, during the period when the treatment liquid is not circulated to the concentration sensor 61 provided in the second treatment liquid discharge portion 54, for example, an inert gas or pure water may be supplied to the concentration sensor 61 to remove the treatment liquid so that no treatment liquid remains.

Claims

1. An etching treatment device using a phosphoric acid aqueous solution, characterized in that: have: A processing tank for etching the substrate using an etching solution obtained by heating a phosphoric acid aqueous solution; a treatment liquid supply unit for supplying an aqueous phosphoric acid solution to the treatment tank; a processing liquid circulation unit that circulates the etching liquid in the processing tank; a processing liquid discharge unit configured to discharge the etching liquid; as well as a control unit that controls the processing liquid supply unit, the processing liquid circulation unit, and the processing liquid discharge unit, wherein the control unit circulates the etching solution by the processing liquid circulation unit, discharges the etching solution from the processing liquid discharge unit, and supplies phosphoric acid aqueous solution from the processing liquid supply unit to the processing tank, The relationship between the etching time of the substrate, the discharge amount of the etching solution during the etching process, the supply amount of the new phosphoric acid aqueous solution, and the silicon concentration in the etching solution is investigated in advance, and the control unit makes the silicon concentration of the etching solution in which the substrate is immersed fall within a specified concentration range by discharging a specified amount of the etching solution during the etching process of the substrate and newly supplying a specified amount of the phosphoric acid aqueous solution, The control unit further performs control using information on the silicon concentration in the etching solution measured at a predetermined timing so that the silicon concentration of the etching solution in which the substrate is immersed falls within a predetermined concentration range.

2. The etching processing device according to claim 1, characterized in that: The predetermined timing is immediately after the etching process on the substrate starts or immediately before the etching process on the substrate ends.

3. The etching processing device according to claim 1 or 2, characterized in that: When the silicon concentration in the etching solution is less than a predetermined value, the substrate processing is continued.

4. The etching processing device according to claim 1 or 2, characterized in that: When the silicon concentration in the etching solution is equal to or higher than a predetermined value, the substrate processing is not performed.

5. The etching processing device according to claim 1 or 2, characterized in that: The etching processing apparatus includes a concentration sensor connected to a control unit and configured to measure the silicon concentration in the etching solution.

6. The etching processing device according to claim 5, characterized in that: The concentration sensor is present in the treatment liquid discharge portion.

7. The etching processing device according to claim 5, characterized in that: The control unit circulates the etching liquid using the processing liquid circulation unit, measures the silicon concentration using the concentration sensor at a predetermined timing, discharges the etching liquid from the processing liquid discharge unit, and supplies a phosphoric acid aqueous solution from the processing liquid supply unit to the processing tank.

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