Substrate processing equipment

Abstract

This eliminates bias in the flow rate of the processing liquid within the processing tank, further suppressing uneven processing on the substrate surface. [Solution] The substrate processing apparatus (100) comprises outer bubble generating tubes (31, 32) and inner bubble generating tubes (33, 34), and each of the outer bubble generating tubes (31, 32) and inner bubble generating tubes (33, 34) has a plurality of discharge holes, each of which includes at least a first discharge hole having a first hole diameter and a second discharge hole having a second hole diameter larger than the first hole diameter.

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus.

Background Art

[0002] Substrates used in electronic components such as semiconductor devices and liquid crystal display devices are known to be processed by a substrate processing apparatus. The substrate can be processed by being immersed in a processing liquid in a processing tank.

[0003] With the miniaturization and / or three-dimensionalization of semiconductor elements formed on semiconductor substrates in recent years, there has been an increasing demand for uniform substrate processing. For example, a NAND element having a three-dimensional structure has a stacked structure provided with a three-dimensional uneven structure. When the processing liquid stays in the recesses of the uneven structure of the element pattern, the liquid replacement in the recesses becomes insufficient. Therefore, in order to sufficiently promote liquid replacement for the entire substrate including the recesses, a bubble generation tube may be arranged below the substrate immersed in the processing tank, and bubbles may be generated from a bubble generator to promote liquid replacement in the processing tank.

[0004] And in such a technique, in order to suppress processing unevenness within the substrate surface in the processing tank, for example, as shown in Patent Document 1, a technique has also been developed in which the gas flow rate supplied to a plurality of bubble generation tubes is made larger for the outer bubble generation tubes than for the inner bubble generation tubes.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the process of diligently developing a technology to suppress uneven processing on the substrate surface within the aforementioned processing tank, the inventors discovered that the structure of the processing tank and other factors cause an imbalance in the flow rate of the processing liquid within the tank. Such an imbalance makes it possible that uneven processing on the substrate surface may occur.

[0007] One aspect of the present invention aims to eliminate bias in the flow rate of the processing liquid within the processing tank and further suppress processing unevenness within the substrate surface. [Means for solving the problem]

[0008] To solve the above problems, a substrate processing apparatus according to one aspect of the present invention comprises a substrate holding section for holding at least one substrate, a processing tank for storing a processing liquid for immersing the substrate held in the substrate holding section, and a plurality of bubble generating tubes for generating bubbles in the processing liquid by supplying gas to the processing liquid, each of the plurality of bubble generating tubes having a plurality of discharge holes for discharging the gas, and the plurality of discharge holes include at least a first discharge hole having a first hole diameter and a second discharge hole having a second hole diameter larger than the first hole diameter.

[0009] In a substrate processing apparatus according to one aspect of the present invention, the first discharge hole is formed in an inner bubble generating tube located below the central region of the substrate immersed in the processing liquid among the plurality of bubble generating tubes, and the second discharge hole may be formed in an outer bubble generating tube located below the outer peripheral region of the substrate immersed in the processing liquid among the plurality of bubble generating tubes.

[0010] A substrate processing apparatus according to one aspect of the present invention comprises: a first gas supply pipe connecting a gas supply source and the outer bubble generating pipe; a second gas supply pipe connecting the gas supply source and the inner bubble generating pipe; a plurality of liquid discharge pipes that generate an upflow flowing upward inside the processing tank by discharging the processing liquid into the processing tank; and a first flow rate control mechanism that controls the flow rate of the gas flowing through the first gas supply pipe and the second gas supply pipe, wherein the outer bubble generating pipe, the inner bubble generating pipe, and the plurality of liquid discharge pipes are connected to the substrate The liquid discharge pipes extend in the direction normal to the main surface, and when viewed from the normal direction, the plurality of liquid discharge pipes are arranged between the outer bubble generating pipe and the inner bubble generating pipe, and the upflow generated by the plurality of liquid discharge pipes generates a downward flow along the side surface of the processing tank after reaching the liquid surface of the processing liquid in the processing tank, and the first flow rate control mechanism may control the flow rate of the gas supplied to the first gas supply pipe so that the bubbles generated by the outer bubble generating pipe rise against the downward flow.

[0011] In a substrate processing apparatus according to one aspect of the present invention, at least one of the plurality of bubble generating tubes has a first discharge hole and a second discharge hole formed along a predetermined arrangement direction, and the predetermined arrangement direction may be a direction in which the substrate holding portion holds the plurality of substrates such that the main surfaces of the plurality of adjacent substrates face each other with a gap between them.

[0012] In a substrate processing apparatus according to one aspect of the present invention, at least one of the plurality of bubble generating tubes is provided with a first discharge hole group consisting of a plurality of first discharge holes continuous along a predetermined arrangement direction, and a second discharge hole group consisting of a plurality of second discharge holes continuous along the arrangement direction, wherein the predetermined arrangement direction may be the direction in which the substrate holding portion holds the plurality of substrates such that the main surfaces of the plurality of adjacent substrates face each other with a gap between them.

[0013] In a substrate processing apparatus according to one aspect of the present invention, the substrate holding portion includes a mounting portion for placing the plurality of substrates and a back plate disposed at one end of the mounting portion and extending vertically along the side wall of the processing tank, and the second discharge hole may be formed on a side further away from the back plate than the first discharge hole.

[0014] In a substrate processing apparatus according to one aspect of the present invention, the processing solution may include a phosphoric acid solution. [Effects of the Invention]

[0015] According to one aspect of the present invention, a substrate processing apparatus can be used to eliminate bias in the flow rate of the processing liquid within the processing tank, thereby further suppressing processing unevenness within the substrate surface. [Brief explanation of the drawing]

[0016] [Figure 1] This is a perspective view illustrating the schematic configuration of a substrate processing apparatus according to an embodiment of the present invention. [Figure 2] Figure 1 is a schematic diagram showing how bubbles are generated inside the inner chamber of the processing tank of the substrate processing apparatus shown. [Figure 3] Figure 1 is a top view of the substrate processing apparatus. [Figure 4] This is a schematic diagram illustrating the general configuration around the processing tank in the substrate processing apparatus shown in Figure 1. [Figure 5] Figure 1 is a schematic diagram illustrating the flow of the processing liquid within the inner tank of the processing chamber of the substrate processing apparatus shown in Figure 1. [Figure 6] This image shows bubbles being discharged from the discharge port of a bubble generating tube. [Figure 7] This graph shows the relationship between the diameter of the discharge port in the bubble generating tube and the diameter of the bubbles discharged from the discharge port in the bubble generating tube. [Figure 8] This is a schematic diagram illustrating the general internal configuration of the inner tank of a processing tank in a substrate processing apparatus according to a modified example of the present invention. [Figure 9]FIG. 8 is a schematic diagram for explaining the schematic configuration inside the inner tank when viewed in the direction of the negative Z-axis.

Embodiments for Carrying out the Invention

[0017] (Configuration of Substrate Processing Apparatus 100) FIG. 1 is a perspective view illustrating the schematic configuration of a substrate processing apparatus 100 according to an embodiment of the present invention. In FIGS. 1 to 5, the direction in which a plurality of outer bubble generation tubes 31 and 32 are arranged is defined as the X-axis direction, the direction in which a plurality of substrates W are arranged is defined as the Y-axis direction, and the direction in which the lifting unit 13 raises and lowers the substrate holding unit 1 is defined as the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other.

[0018] As shown by reference numeral 101 in FIG. 1, the substrate processing apparatus 100 includes a substrate holding unit 1 and a processing tank 2. The substrate processing apparatus 100 is a processing apparatus that processes at least one substrate W. Specifically, the substrate processing apparatus 100 processes the substrate W so as to perform at least one of etching, surface treatment, property imparting, processing film formation, removal of at least a part of the film, impurity removal, and cleaning on the substrate W.

[0019] The impurities removed by the substrate processing apparatus 100 are, for example, fine particles, metals, residues, or organic substances such as photoresist attached to the surface of the substrate W. Further, the film removed by the substrate processing apparatus 100 is, for example, a natural oxide film or a nitride film formed on the surface of the substrate W.

[0020] The substrate W is in the form of a thin plate, for example, a thin substantially disk-shaped plate. In this specification, "substantially" is not limited to the case of being exactly the same, and includes a concept including at least one of an error and deformation that do not lose identity. The substrate W is, for example, a semiconductor wafer, a substrate for a liquid crystal display device, a substrate for a plasma display, or a substrate for a field emission display (FED). Further, the substrate W is, for example, a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a substrate for a photomask, a ceramic substrate, or a substrate for a solar cell.

[0021] The substrate processing apparatus 100 is a so-called batch-type processing apparatus capable of processing a lot of multiple substrates W at once. However, the substrate processing apparatus 100 may also process the substrates W one at a time.

[0022] The substrate processing apparatus 100 processes the substrate W with a processing solution L. The processing solution L is a cleaning solution for cleaning the surface of the substrate W. Preferably, the processing solution L is a processing solution containing phosphoric acid. In this case, the substrate processing apparatus 100 removes the nitride film formed on the surface of the substrate W.

[0023] The treatment solution L may be, for example, a mixture of sulfuric acid and hydrogen peroxide (SPM), or a mixture of ammonium hydroxide and hydrogen peroxide (APM). Alternatively, the treatment solution L may contain a mixture of hydrochloric acid and hydrogen peroxide (HPM), or a treatment solution containing diluted hydrofluoric acid (DHF).

[0024] Furthermore, the treatment solution L may be a mixture of hydrofluoric acid and hydrogen peroxide (FPM), or a mixture of ammonium fluoride and hydrofluoric acid (BHF).

[0025] (Configuration of substrate holding section 1 and processing tank 2) The substrate holder 1 holds at least one substrate W. The normal direction of the main surface WS of the substrate W held by the substrate holder 1 is the Y-axis direction. Multiple substrates W are arranged in a line along the Y-axis direction. In other words, multiple substrates W are arranged substantially parallel to the XZ plane. Furthermore, each of the multiple substrates W extends in the X-axis direction and the Z-axis direction.

[0026] The substrate holding unit 1 is specifically a lifter and includes a back plate 11, a mounting unit 12, and a lifting unit 13. The back plate 11 is a plate extending in the XZ plane. The mounting unit 12 is, for example, a holding rod extending in the negative Y-axis direction from one surface of the back plate 11. For example, three mounting units 12 extend in the negative Y-axis direction from one surface of the back plate 11. The mounting unit 12 contacts the lower edge of each substrate W when the multiple substrates W are aligned at predetermined intervals. In this way, the mounting unit 12 holds the multiple substrates W and places the multiple substrates W on it.

[0027] The lifting unit 13 raises and lowers the substrate holder 1 in the Z-axis direction. By moving the substrate holder 1 in the negative Z-axis direction, the lifting unit 13 immerses the multiple substrates W held by the substrate holder 1 in the processing liquid L stored in the processing tank 2, as shown by reference numeral 102 in Figure 1.

[0028] The processing tank 2 stores a processing liquid L for immersing the substrates W held by the substrate holding unit 1. The processing tank 2 has a double-tank structure including an inner tank 21 and an outer tank 22. The inner tank 21 and the outer tank 22 each have an upper opening that opens upward. The inner tank 21 stores the processing liquid L and is configured to accommodate multiple substrates W. The outer tank 22 is provided outside the inner tank 21. The outer tank 22 stores the processing liquid L that overflows from the inner tank 21.

[0029] (Configuration of outer bubble generating tube, inner bubble generating tube, and liquid discharge tube) Figure 2 is a schematic diagram showing how bubbles are generated in the inner tank 21 of the processing tank 2 of the substrate processing apparatus 100 shown in Figure 1. Figure 2 omits the illustration of the substrate holding section 1. As shown in Figure 2, the substrate processing apparatus 100 includes a plurality of outer bubble generating tubes 31, 32, a plurality of inner bubble generating tubes 33, 34, and a plurality of liquid discharge tubes 41, 42. The outer bubble generating tubes 31, 32 and the inner bubble generating tubes 33, 34 are examples of bubble generating tubes.

[0030] The outer bubble generating tubes 31 and 32 are positioned inside the inner tank 21, below the outer peripheral region of the substrate W immersed in the processing liquid L, and generate bubbles in the processing liquid L by supplying gas to the processing liquid L. The outer peripheral region of the substrate W is, when viewed from the Y-axis direction, for example, the region from a position that is 0.6 times the radius of the main surface WS of the substrate W to the edge of the substrate W, in a direction parallel to the center of the substrate W.

[0031] The inner bubble generating tubes 33 and 34 are positioned inside the inner tank 21, below the central region of the substrate W immersed in the processing liquid L, and generate bubbles in the processing liquid L by supplying gas to the processing liquid L. The central region of the substrate W is the region of the substrate W other than the outer peripheral region of the substrate W when viewed from the Y-axis direction, for example, the region from the center of the substrate W to a position that is 0.6 times the radius in a direction parallel to the main surface WS of the substrate W relative to the center of the substrate W. When viewed from the Y-axis direction, the inner bubble generating tubes 33 and 34 are located closer to the center of the substrate W than the outer bubble generating tubes 31 and 32.

[0032] Bubbles generated in the processing liquid L by the outer bubble generating tubes 31, 32 and the inner bubble generating tubes 33, 34 float up within the processing liquid L and reach the liquid level LS of the processing liquid L in the inner tank 21. The liquid level LS of the processing liquid L is the interface between the processing liquid L in the inner tank 21 and a gas such as air or a predetermined atmosphere. As the bubbles float up within the processing liquid L, they come into contact with the surface of the substrate W.

[0033] The liquid discharge pipes 41 and 42 discharge the processing liquid L into the inner tank 21, generating an upflow that flows upward within the inner tank 21. The liquid discharge pipes 41 and 42 discharge the processing liquid L in the direction indicated by the arrows in Figure 2. In other words, when viewed from the Y-axis direction, the liquid discharge pipes 41 and 42 discharge the processing liquid L toward a virtual center line CL that passes through the center of the substrate W and extends in the Z-axis direction, and toward the positive Z-axis direction. However, the discharge direction of the processing liquid L by the liquid discharge pipes 41 and 42 is not limited to this.

[0034] When viewed from the Y-axis direction, the liquid discharge pipes 41 and 42 are positioned between the outer bubble generating pipes 31 and 32 and the inner bubble generating pipes 33 and 34. Specifically, when viewed from the Y-axis direction, the liquid discharge pipe 41 is positioned in the X-axis direction between the outer bubble generating pipe 31 and the inner bubble generating pipe 33, and the liquid discharge pipe 42 is positioned in the X-axis direction between the outer bubble generating pipe 32 and the inner bubble generating pipe 34.

[0035] (Configuration of the upper side of the substrate processing apparatus 100) Figure 3 is a top view of the substrate processing apparatus 100 shown in Figure 1. Figure 3 omits the substrate holding section 1 and the outer tank 22. As shown in Figure 3, multiple substrates W are arranged in a single row in the Y-axis direction and at equal intervals. For example, the spacing between adjacent substrates W is between 2 mm and 20 mm.

[0036] The outer bubble generating tubes 31, 32, the inner bubble generating tubes 33, 34, and the liquid discharge tubes 41, 42 are located on the negative Z-axis side of the substrate W held by the substrate holding section 1. For example, the outer bubble generating tubes 31, 32, the inner bubble generating tubes 33, 34, and the liquid discharge tubes 41, 42 are located near the bottom surface of the inner tank 21. The outer bubble generating tubes 31, 32, the inner bubble generating tubes 33, 34, and the liquid discharge tubes 41, 42 extend in the Y-axis direction and also extend parallel to each other.

[0037] As shown in Figures 2 and 3, the outer bubble generating tube 31 has multiple discharge holes 31A for discharging gas. In other words, the outer bubble generating tube 31 has multiple discharge holes 31A. The multiple discharge holes 31A are arranged in a line in the Y-axis direction and at equal intervals. The spacing between the multiple discharge holes 31A is approximately the same as the spacing between the substrates W. When viewed from the Z-axis direction, the multiple discharge holes 31A are located between the substrates W.

[0038] Similar to the outer bubble generating pipe 31, the outer bubble generating pipe 32 has multiple discharge holes 32A, the inner bubble generating pipe 33 has multiple discharge holes 33A, and the inner bubble generating pipe 34 has multiple discharge holes 34A. Also, similar to the outer bubble generating pipe 31, the liquid discharge pipe 41 has multiple discharge holes 41A, and the liquid discharge pipe 42 has multiple discharge holes 42A.

[0039] Each of the multiple discharge holes 31A to 34A includes at least a first discharge hole having a first diameter and a second discharge hole having a second diameter larger than the first diameter. Specifically, for example, discharge holes 33A and 34A have a first diameter, and discharge holes 31A and 32A have a second diameter. In other words, the diameters of discharge holes 31A and 32A are larger than the diameters of discharge holes 33A and 34A. The diameters of discharge holes 31A and 32A are approximately the same, and the diameters of discharge holes 33A and 34A are approximately the same.

[0040] The second hole diameter is preferably approximately three times the first hole diameter. For example, the first hole diameter may be 0.26 mm and the second hole diameter may be 0.78 mm. Alternatively, the second hole diameter may be approximately 1.3 times the first hole diameter.

[0041] Discharge holes 33A and 34A are examples of first discharge holes, and discharge holes 31A and 32A are examples of second discharge holes. Furthermore, as described above, discharge hole 33A is formed in the inner bubble generating tube 33 of the multiple bubble generating tubes, and discharge hole 34A is formed in the inner bubble generating tube 34 of the multiple bubble generating tubes. Also, discharge hole 31A is formed in the outer bubble generating tube 31 of the multiple bubble generating tubes, and discharge hole 32A is formed in the outer bubble generating tube 32 of the multiple bubble generating tubes.

[0042] The spacing between the multiple discharge holes 31A and 32A is approximately the same, and the spacing between the multiple discharge holes 33A and 34A is also approximately the same. Furthermore, the spacing between the multiple discharge holes 41A and 42A is also approximately the same.

[0043] Furthermore, each of the multiple discharge holes 41A, 42A may have either a first or second diameter. In other words, the diameter of each of the multiple discharge holes 41A, 42A may be approximately the same as the respective diameters of the discharge holes 31A, 32A, or the respective diameters of the discharge holes 33A, 34A.

[0044] If the diameters of the multiple discharge holes 41A and 42A are approximately the same as the diameters of the multiple discharge holes 31A and 32A, then the spacing between the multiple discharge holes 41A and 42A is approximately the same as the spacing between the multiple discharge holes 31A and 32A. Also, if the diameters of the multiple discharge holes 41A and 42A are approximately the same as the diameters of the multiple discharge holes 33A and 34A, then the spacing between the multiple discharge holes 41A and 42A is approximately the same as the spacing between the multiple discharge holes 33A and 34A.

[0045] As described above, the multiple discharge holes 31A to 34A each include at least a first discharge hole having a first diameter and a second discharge hole having a second diameter larger than the first diameter. This eliminates bias in the flow rate of the processing liquid L within the inner tank 21, allowing bubbles to be uniformly distributed across the surface of the substrate W, and further suppressing processing unevenness within the surface of the substrate W. As a result, an improvement in yield can be expected.

[0046] Furthermore, surface treatment of the substrate W using a treatment solution L containing phosphoric acid takes more time than surface treatment of the substrate W using a treatment solution containing chemicals other than phosphoric acid. Therefore, as described above, further improvement in yield can be expected by having at least a first discharge hole having a first diameter and a second discharge hole having a second diameter larger than the first diameter among the multiple discharge holes 31A to 34A.

[0047] The outer bubble generating tubes 31, 32 and the inner bubble generating tubes 33, 34 are preferably made of a material containing, for example, quartz. In this case, it is possible to make it difficult for the bubbles generated from the outer bubble generating tubes 31, 32 and the inner bubble generating tubes 33, 34 to come into contact with each other, and to distribute the bubbles uniformly across the surface of the substrate W. The outer bubble generating tubes 31, 32 and the inner bubble generating tubes 33, 34 may also be made of a material containing polyether ether ketone (PEEK).

[0048] The substrate processing apparatus 100 comprises a gas supply source 5, a first flow rate control mechanism 6, a second flow rate control mechanism 7, a plurality of first gas supply pipes 51, 52, a plurality of second gas supply pipes 53, 54, and a plurality of liquid supply pipes 71, 72. The first gas supply pipe 51 connects the gas supply source 5 to the outer bubble generating pipe 31, and the first gas supply pipe 52 connects the gas supply source 5 to the outer bubble generating pipe 32. The second gas supply pipe 53 connects the gas supply source 5 to the inner bubble generating pipe 33, and the second gas supply pipe 54 connects the gas supply source 5 to the inner bubble generating pipe 34.

[0049] The liquid supply pipes 71 and 72 are connected to the liquid discharge pipes 41 and 42. Specifically, the liquid supply pipe 71 connects the second flow control mechanism 7 to the liquid discharge pipe 41, and the liquid supply pipe 72 connects the second flow control mechanism 7 to the liquid discharge pipe 42.

[0050] The gas supply source 5 stores the gas and supplies it to the outer bubble generating tube 31 via the first gas supply pipe 51 and to the outer bubble generating tube 32 via the first gas supply pipe 52. The gas supply source 5 also supplies gas to the inner bubble generating tube 33 via the second gas supply pipe 53 and to the inner bubble generating tube 34 via the second gas supply pipe 54. The gas supplied by the gas supply source 5 is, for example, nitrogen.

[0051] The first flow rate control mechanism 6 includes a plurality of first flow rate control mechanisms 61, 62, 63, and 64, and controls the flow rate of gas flowing through the first gas supply pipes 51 and 52 and the second gas supply pipes 53 and 54.

[0052] The first flow rate control mechanism 61 is provided in the first gas supply pipe 51 and controls the flow rate of the gas flowing through the first gas supply pipe 51. The first flow rate control mechanism 61 includes, for example, an adjustment valve (not shown) that adjusts the flow rate of the gas flowing through the first gas supply pipe 51. The adjustment valve includes a valve body (not shown) with a valve seat inside, a valve element (not shown) that opens and closes the valve seat, and an actuator (not shown) that moves the valve element between an open position and a closed position.

[0053] The first flow rate control mechanism 62 is provided in the first gas supply pipe 52 and controls the flow rate of the gas flowing through the first gas supply pipe 52. The first flow rate control mechanism 63 is provided in the second gas supply pipe 53 and controls the flow rate of the gas flowing through the second gas supply pipe 53, and the first flow rate control mechanism 64 is provided in the second gas supply pipe 54 and controls the flow rate of the gas flowing through the second gas supply pipe 54. Each of the first flow rate control mechanisms 62 to 64 includes an adjustment valve, similar to the first flow rate control mechanism 61.

[0054] The second flow rate control mechanism 7 is located outside the treatment tank 2 and controls the flow rate of the treatment liquid L supplied to the liquid supply pipes 71 and 72. The treatment liquid L flows from the second flow rate control mechanism 7 through the liquid supply pipe 71 to the liquid discharge pipe 41, and from the second flow rate control mechanism 7 through the liquid supply pipe 72 to the liquid discharge pipe 42. The second flow rate control mechanism 7 may also recirculate the liquid that has been used once as the treatment liquid L in the treatment tank 2. The flow rate of the treatment liquid L supplied to each of the liquid supply pipes 71 and 72 is, for example, 40 L / min or less, or 100 L / min or less.

[0055] (Configuration of the area surrounding the processing tank 2) Figure 4 is a schematic diagram illustrating the general configuration around the processing tank 2 in the substrate processing apparatus 100 shown in Figure 1. The second flow rate control mechanism 7 circulates the processing liquid L stored in the processing tank 2 and supplies the processing liquid L to the liquid supply pipes 71 and 72. The second flow rate control mechanism 7 includes piping 81, a pump 82, a heater 83, a filter 84, a control valve 85, and a valve 86. The pump 82, heater 83, filter 84, control valve 85, and valve 86 are arranged in this order from upstream to downstream of piping 81.

[0056] Piping 81 guides the processed liquid L discharged from the outer tank 22 to the liquid supply pipes 71 and 72. Piping 81 connects the outer tank 22 to the liquid supply pipes 71 and 72 and also branches off to the liquid supply pipes 71 and 72. Pump 82 sends the processed liquid L from the outer tank 22 to the liquid supply pipes 71 and 72. Heater 83 adjusts the temperature of the processed liquid L by heating the processed liquid L flowing through piping 81. Filter 84 filters the processed liquid L flowing through piping 81.

[0057] The regulating valve 85 adjusts the flow rate of the processing liquid L supplied to the liquid supply pipes 71 and 72. Specifically, the regulating valve 85 includes a valve body (not shown) with a valve seat inside, a valve element (not shown) that opens and closes the valve seat, and an actuator (not shown) that moves the valve element between an open position and a closed position. Valve 86 opens and closes the flow path from piping 81 to the liquid supply pipes 71 and 72.

[0058] The substrate processing apparatus 100 includes a processing liquid supply unit 110. The processing liquid supply unit 110 supplies processing liquid L to the processing tank 2. The processing liquid supply unit 110 includes a processing liquid supply source 111, a nozzle 112, piping 113, and a valve 114.

[0059] The processing liquid supply source 111 supplies processing liquid L to the piping 113. The nozzle 112 is connected to the piping 113 and discharges the processing liquid L into the processing tank 2. The valve 114 is installed in the piping 113 and opens and closes the flow path of the piping 113. When the valve 114 is opened, the processing liquid L discharged by the nozzle 112 is supplied into the processing tank 2.

[0060] The substrate processing apparatus 100 includes a drainage section 120. The drainage section 120 discharges the processing liquid L stored in the inner tank 21. The drainage section 120 includes a drainage pipe 121 and a valve 122. The bottom wall of the inner tank 21 is connected to the drainage pipe 121. The valve 122 is provided on the drainage pipe 121. When the valve 122 opens, the processing liquid L stored in the inner tank 21 is discharged to the outside of the processing tank 2 through the drainage pipe 121. The discharged processing liquid L is sent to a drainage processing apparatus (not shown) for further processing.

[0061] The substrate processing apparatus 100 includes a control unit 9. The control unit 9 includes a CPU (Central Processing Unit) 91 and memory 92 as processors. The control unit 9 may also include, for example, a microprocessing unit (MPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), or a field-programmable gateway (FPGA) as processors. Furthermore, the control unit 9 may also include a digital signal processor (DSP), a dataflow processor (DFP), or a neural processing unit (NPU) as processors.

[0062] Memory 92 may be one or more hard disks (HDs), random access memory (RAM), read-only memory (ROM), or storage devices of a distributed computing system. Alternatively, memory 92 may be an optical disc (e.g., a compact disc (CD), digital versatile disc (DVD), or Blu-ray disc (BD, registered trademark)), a flash memory device, or a memory card.

[0063] The control unit 9 controls various operations of the substrate processing device 100. For example, the control unit 9 controls the first flow rate control mechanism 6, the second flow rate control mechanism 7, the lifting unit 13, the valve 114, and the valve 122.

[0064] Specifically, regarding the control of the first flow control mechanism 6 and the second flow control mechanism 7, the control unit 9 controls each of the first flow control mechanisms 61 to 64, as well as the pump 82, the heater 83, the adjustment valve 85, and the valve 86.

[0065] (Flow of treatment liquid L) Figure 5 is a schematic diagram illustrating the flow of processing liquid L within the inner tank 21 of the processing tank 2 of the substrate processing apparatus 100 shown in Figure 1. In Figure 5, reference numerals 501 and 502 indicate the flow of processing liquid L F1 due to bubbles generated in the outer bubble generating pipes 31 and 32 and the inner bubble generating pipes 33 and 34, respectively, indicated by dotted arrows, and the flow of processing liquid L F2 due to the discharge of processing liquid L by the liquid discharge pipes 41 and 42 is indicated by solid arrows.

[0066] As shown by reference numeral 501 in Figure 5, let's consider the case where neither liquid discharge pipe 41 nor 42 is discharging the processing liquid L into the inner tank 21, and the outer bubble generating pipes 31, 32 and the inner bubble generating pipes 33, 34 are supplying gas to the processing liquid L. In this case, the flow F1 of the processing liquid L due to the bubbles generated in the outer bubble generating pipes 31, 32 and the inner bubble generating pipes 33, 34 will be a flow in the positive Z-axis direction. In the case of reference numeral 501 in Figure 5, it is assumed that the diameters of the discharge holes 31A, 32A and the diameters of the discharge holes 33A, 34A are approximately the same.

[0067] As shown by reference numeral 502 in Figure 5, let's consider the case where liquid discharge pipes 41 and 42 discharge the processed liquid L into the inner tank 21, and the diameters of the discharge holes 31A and 32A are approximately the same as the diameters of the discharge holes 33A and 34A.

[0068] In this case, the liquid discharge pipes 41 and 42 generate an upflow along the virtual centerline CL. The flow F2 of the processed liquid L discharged by the liquid discharge pipes 41 and 42 travels in the positive Z-axis direction along the virtual centerline CL, reaches the liquid level LS of the processed liquid L in the inner tank 21, and then flows downward along the side surface 2S of the inner tank 21. The side surface 2S is the inner surface of the inner tank 21 that is approximately parallel to the YZ plane.

[0069] The flow F1 of the processing liquid L caused by bubbles generated in the inner bubble generation tubes 33 and 34 is a flow in the positive Z-axis direction. In addition, the flow F1 of the processing liquid L caused by bubbles generated in the outer bubble generation tubes 31 and 32 is a downward flow of the flow F2 that descends along the side surface 2S of the inner tank 21, and as a result, it is a flow in the positive Z-axis direction along the virtual centerline CL.

[0070] In other words, flow F1 is directed in the positive Z-axis direction along the virtual centerline CL, avoiding the downward flow of flow F2 that descends from the liquid surface LS along the side surface 2S of the inner tank 21, making it difficult for bubbles to spread to the outer peripheral region of the substrate W. Furthermore, flow F1 changes according to the flow rate of the processing liquid L discharged by the liquid discharge pipes 41 and 42.

[0071] Therefore, consider the case in Figure 5, indicated by reference numeral 503, where liquid discharge pipes 41 and 42 discharge the processed liquid L into the inner tank 21, and discharge holes 33A and 34A are first discharge holes having a first diameter, and discharge holes 31A and 32A are second discharge holes having a second diameter larger than the first diameter. In this case, the diameter of the bubbles generated in the outer bubble generating pipes 31 and 32 will be larger than the diameter of the bubbles generated in the inner bubble generating pipes 33 and 34.

[0072] Therefore, the flow F3 of the treatment liquid L due to bubbles generated in the outer bubble generation tubes 31 and 32 is stronger than the flow F1 of the treatment liquid L due to bubbles generated in the inner bubble generation tubes 33 and 34. In addition, the bubbles generated in the outer bubble generation tubes 31 and 32 are less affected by the downdraft flow that descends from the liquid surface LS along the side surface 2S of the inner tank 21, which is part of the flow F2 shown by reference numeral 503 in Figure 5, and are more likely to rise in the positive Z-axis direction.

[0073] As a result, flow F3 becomes an upward flow in the positive Z-axis direction, counteracting the downward flow of flow F2 that descends along the side surface 2S of the inner tank 21. Therefore, bubbles can be more easily distributed to the outer peripheral region of the substrate W, improving liquid displacement.

[0074] As described above, the upflow generated by the liquid discharge pipes 41 and 42 generates a downward flow along the side surface 2S of the inner tank 21 after reaching the liquid level LS of the processed liquid L in the inner tank 21. The first flow rate control mechanism 6 controls the flow rate of the gas supplied to the first gas supply pipes 51 and 52 so that the bubbles generated by the outer bubble generating pipes 31 and 32 rise against the downward flow.

[0075] (Influence of pore size on bubble diameter) Figure 6 is an image showing bubbles discharged from the discharge holes of a bubble generating tube. In Figure 6, the bubble generating tube is located inside the inner tank 21 that stores the processing liquid L. In Figure 6, the flow rate of the gas supplied to the bubble generating tube is 1 L / min, the outer diameter of the bubble generating tube is 8 mm, the thickness of the bubble generating tube is 2 mm, and the number of discharge holes in the bubble generating tube is 50.

[0076] In Figure 6, reference numeral 601 shows an image illustrating how bubbles are generated in a bubble generating tube having multiple discharge holes with a diameter of 0.26 mm, and reference numeral 602 shows an image illustrating how bubbles are generated in a bubble generating tube having multiple discharge holes with a diameter of 0.46 mm. Reference numeral 603 shows an image illustrating how bubbles are generated in a bubble generating tube having multiple discharge holes with a diameter of 0.76 mm.

[0077] In Figure 6, reference numeral 601 indicates that the diameter of the bubbles generated by a bubble generating tube having multiple discharge holes with a diameter of 0.26 mm was approximately 3 mm. In Figure 6, reference numeral 602 indicates that the diameter of the bubbles generated by a bubble generating tube having multiple discharge holes with a diameter of 0.46 mm was approximately 4.3 mm. In Figure 6, reference numeral 603 indicates that the diameter of the bubbles generated by a bubble generating tube having multiple discharge holes with a diameter of 0.76 mm was approximately 5.9 mm.

[0078] Therefore, the larger the pore diameter, the larger the diameter of the bubbles generated by the bubble generating tube. In other words, the diameter of the bubbles generated in the outer bubble generating tubes 31 and 32 is larger than the diameter of the bubbles generated in the inner bubble generating tubes 33 and 34.

[0079] (Regarding the diameter of the bubbles) Figure 7 is a graph showing the relationship between the diameter of the discharge holes in the bubble generating tube and the diameter of the bubbles discharged from those holes. In Figure 7, the outer diameter of the bubble generating tube is 8 mm, the thickness of the bubble generating tube is 2 mm, and the number of discharge holes in the bubble generating tube is 50. In Figure 7, the horizontal axis represents the diameter of the discharge holes [mm] in the bubble generating tube, and the vertical axis represents the diameter of the bubbles discharged from those holes [mm].

[0080] For graph G1 shown in Figure 7, the gas flow rate supplied to the bubble generating tube was set to 1 L / min, and the diameter of the discharge port of the bubble generating tube was changed twice. The diameters of 20 bubbles generated by the bubble generating tube were then measured. The average values ​​of the diameters of the 20 measured bubbles were plotted as three points.

[0081] Then, when we find the approximate line for the three plotted points, the equation of the approximate line for graph G1 is y = 5.92x + 1.47. x is the diameter of the discharge hole in the bubble generating tube, and y is the diameter of the bubble generated by the bubble generating tube.

[0082] Furthermore, for graph G2 shown in Figure 7, the diameter of the bubbles generated by the bubble generating tube was measured with a gas flow rate of 3 L / min supplied to the bubble generating tube. The measurement conditions for graph G2 are the same as those for graph G1, except that the gas flow rate supplied to the bubble generating tube is different.

[0083] When we find the approximate line for the three points plotted in graph G2, the equation of the approximate line in graph G2 is y = 5.61x + 2.37. x is the diameter of the discharge hole in the bubble generating tube, and y is the diameter of the bubble generated by the bubble generating tube. Therefore, in both graphs G1 and G2, the larger the diameter of the discharge hole, the larger the diameter of the bubble.

[0084] In other words, the diameter of the bubbles generated from the outer bubble generating tubes 31 and 32 is larger than the diameter of the bubbles generated from the inner bubble generating tubes 33 and 34. Also, the amount of bubbles generated from the outer bubble generating tubes 31 and 32 is greater than the amount of bubbles generated from the inner bubble generating tubes 33 and 34.

[0085] (modified version) Figure 8 is a schematic diagram illustrating the general internal configuration of the inner tank 21 of the processing tank 2 in a substrate processing apparatus according to a modified example of the present invention. Figure 9 is a schematic diagram illustrating the general internal configuration of the inner tank 21 when viewed in the negative Z-axis direction as shown in Figure 8. Note that the liquid discharge pipe 42 is omitted in the diagram indicated by reference numeral 801 in Figure 8, and the mounting section 12, the first gas supply pipes 51, 52, the second gas supply pipes 53, 54, and the liquid supply pipes 71, 72 are omitted in Figure 9.

[0086] The modified substrate processing apparatus has outer bubble generating tubes 31B and 32B corresponding to the outer bubble generating tubes 31 and 32 in the substrate processing apparatus 100, and inner bubble generating tubes 33B and 34B corresponding to the inner bubble generating tubes 33 and 34 in the substrate processing apparatus 100.

[0087] In Figure 8, reference numeral 801 indicates a view of the inside of the inner tank 21 as seen in the positive X-axis direction, and reference numeral 802 indicates a view of the inner tank 21 as seen in the negative Y-axis direction, showing the structure near the side wall 2W on the negative Y-axis side of the inner tank 21.

[0088] As shown by reference numeral 801 in Figure 8, the back plate 11 is positioned at one end 12A on the positive Y-axis side of the mounting section 12 and extends vertically along the side wall 2X on the positive Y-axis side of the inner tank 21. The vertical direction is the Z-axis direction.

[0089] Furthermore, as shown by reference numeral 802 in Figure 8, the modified substrate processing apparatus includes a sensor cover 150, a concentration sensor 151, a temperature sensor 160, and a fixing part 170. The first gas supply pipes 51, 52, the second gas supply pipes 53, 54, the sensor cover 150, and the fixing part 170 are provided on the side wall 2W of the inner tank 21.

[0090] The sensor cover 150 houses the concentration sensor 151. The concentration sensor 151 measures the concentration of components contained in the processing liquid L. For example, if the processing liquid L is a processing liquid containing phosphoric acid, the concentration sensor 151 is a sensor that measures the concentration of phosphoric acid contained in the processing liquid L. The temperature sensor 160 measures the temperature of the processing liquid L in the inner tank 21. The fixing part 170 fixes the first gas supply pipes 51, 52, the second gas supply pipes 53, 54 and the temperature sensor 160 to the side wall 2W.

[0091] As described above, the structure of the side wall 2W differs from the structure of the side wall 2X, resulting in an asymmetrical structure for the modified substrate processing apparatus. Consequently, the flow of the processing liquid L on the side wall 2W differs from the flow of the processing liquid L on the side wall 2X. For example, the flow velocity of the processing liquid L on the side wall 2W is slower than the flow velocity of the processing liquid L on the side wall 2X. Therefore, the structure of the substrate processing apparatus is preferably as shown in Figure 9.

[0092] As shown in Figure 9, the outer bubble generating tube 31B has multiple discharge holes 31C and 31D. Similarly, the outer bubble generating tube 32B has multiple discharge holes 32C and 32D, the inner bubble generating tube 33B has multiple discharge holes 33C and 33D, and the inner bubble generating tube 34B has multiple discharge holes 34C and 34D. Discharge holes 31C to 34C are examples of first discharge holes, and discharge holes 31D to 34D are examples of second discharge holes.

[0093] The multiple discharge holes 31C-34C, 31D-34D each include at least a first discharge hole having a first diameter and a second discharge hole having a second diameter larger than the first diameter. Specifically, for example, discharge holes 31C-34C have a first diameter, and discharge holes 31D-34D have a second diameter. In other words, the diameter of each discharge hole 31D-34D is larger than the diameter of each discharge hole 31C-34C. The diameters of discharge holes 31C-34C are approximately the same, and the diameters of discharge holes 31D-34D are approximately the same.

[0094] Therefore, in each of the outer bubble generating tubes 31B, 32B and the inner bubble generating tubes 33B, 34B, a first discharge hole and a second discharge hole are formed along a predetermined alignment direction. This predetermined alignment direction is the direction in which the substrate holding part 1 holds multiple substrates W such that the main surfaces WS of the multiple adjacent substrates W face each other with a gap between them. Furthermore, the above predetermined alignment direction is the Y-axis direction. The spacing between discharge holes 31C to 34C is approximately the same, and the spacing between discharge holes 31D to 34D is approximately the same.

[0095] In at least one of the outer bubble generating tubes 31B, 32B and the inner bubble generating tubes 33B, 34B, a first discharge hole and a second discharge hole may be formed along the Y-axis direction. In other words, in at least one of the outer bubble generating tubes 31B, 32B and the inner bubble generating tubes 33B, 34B, a discharge hole having a first diameter and a discharge hole having a second diameter may be formed along the Y-axis direction. In the outer bubble generating tubes 31B, 32B and the inner bubble generating tubes 33B, 34B, other than those in which the first and second discharge holes are formed, only the first discharge hole may be formed.

[0096] Furthermore, the discharge holes 31D to 34D are formed on the side further away from the back plate 11 than the discharge holes 31C to 34C. In other words, the discharge holes 31D to 34D are formed on the side closer to the side wall 2W within the inner tank 21 than the discharge holes 31C to 34C, and the discharge holes 31C to 34C are formed on the side closer to the side wall 2X within the inner tank 21 than the discharge holes 31D to 34D.

[0097] Here, the side wall 2W side has the first gas supply pipes 51, 52, the second gas supply pipes 53, 54, the sensor cover 150, and the temperature sensor 160. For this reason, the processing liquid L and gas flow less easily on the side wall 2W side than on the side wall 2X side. In other words, the upflow rate of the processing liquid L on the side wall 2W side is less than the upflow rate of the processing liquid L on the side wall 2X side. Therefore, by forming the discharge holes 31D to 34D further away from the back plate 11 than the discharge holes 31C to 34C, bubbles can be distributed uniformly on both the side wall 2W side and the side wall 2X side, and the stagnation of the processing liquid L can be reduced.

[0098] Furthermore, in each of the outer bubble generating tubes 31B, 32B and the inner bubble generating tubes 33B, 34B, multiple discharge holes may be formed such that the hole diameter gradually increases as the direction is in the negative Y-axis direction. Specifically, of two discharge holes adjacent to each other in the Y-axis direction, the hole diameter of the discharge hole further away from the back plate 11 is larger than the hole diameter of the discharge hole closer to the back plate 11.

[0099] Furthermore, the outer bubble generating tube 31B has a discharge hole group 31G1 consisting of multiple discharge holes 31C that are continuous along the Y-axis direction, and a discharge hole group 31G2 consisting of multiple discharge holes 31D that are continuous along the Y-axis direction. Similarly, the outer bubble generating tube 32B has a discharge hole group 32G1 consisting of multiple discharge holes 32C, and a discharge hole group 32G2 consisting of multiple discharge holes 32D.

[0100] Furthermore, similar to the outer bubble generating tube 31B, the inner bubble generating tube 33B is formed with a discharge hole group 33G1 consisting of multiple discharge holes 33C and a discharge hole group 33G2 consisting of multiple discharge holes 33D. In addition, the inner bubble generating tube 34B is formed with a discharge hole group 34G1 consisting of multiple discharge holes 34C and a discharge hole group 34G2 consisting of multiple discharge holes 34D. Discharge hole groups 31G1 to 34G1 are examples of the first discharge hole group, and discharge hole groups 31G2 to 34G2 are examples of the second discharge hole group.

[0101] In at least one of the outer bubble generating tubes 31B, 32B and the inner bubble generating tubes 33B, 34B, a first discharge hole group consisting of a plurality of first discharge holes continuous along the Y-axis direction and a second discharge hole group consisting of a plurality of second discharge holes continuous along the Y-axis direction may be formed. In the outer bubble generating tubes 31B, 32B and the inner bubble generating tubes 33B, 34B that do not have the first and second discharge hole groups formed, only the first discharge hole group may be formed.

[0102] Now, let's consider the case where the substrate holder 1 holds 50 substrates W. In this case, counting the number of substrates W from the side wall 2X, and viewing from the positive Z-axis direction, ejection holes 31C to 34C may be formed between the 1st to 40th substrates W, and ejection holes 31D to 34D may be formed between the 41st to 50th substrates W.

[0103] Furthermore, counting the number of substrates W from the side wall 2X, and viewing from the positive Z-axis direction, a first discharge hole may be formed between the 1st to 10th substrates W, and a third discharge hole may be formed between the 11th to 40th substrates W. A second discharge hole may also be formed between the 41st to 50th substrates W. In this case, the first hole diameter of the first discharge hole may be approximately 0.7 times the third hole diameter of the third discharge hole, and the second hole diameter of the second discharge hole may be approximately 1.3 times the third hole diameter.

[0104] [Examples of implementation using software] The function of the substrate processing apparatus 100 (hereinafter referred to as "the apparatus") is a program that causes the apparatus to function as a computer, and can be realized by a program that causes the apparatus to function as a control block (particularly the control unit 9).

[0105] In this case, the device includes a computer having at least one control device (e.g., a processor such as a CPU 91) and at least one storage device (e.g., memory 92) as hardware for executing the program. By executing the program using this control device and storage device, each of the functions described in the above embodiment is realized.

[0106] The above program may be recorded on one or more computer-readable recording media, not temporary ones. These recording media may or may not be provided by the above device. In the latter case, the program may be supplied to the above device via any wired or wireless transmission medium.

[0107] Furthermore, some or all of the functions of the control block described above can also be realized by logic circuits. For example, an integrated circuit in which a logic circuit that functions as the control block described above is formed is also included in the scope of the present invention.

[0108] [Additional Notes] The present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the multiple technical means disclosed in the embodiments are also included in the technical scope of the present invention. [Explanation of Symbols]

[0109] 100 Substrate Processing Equipment 1 Board holding part 2. Treatment tank 2S side 5. Gas supply source 6. First flow control mechanism 11 Back plate 12 Mounting section 31, 32 Outer bubble generating tube 33, 34 Inner bubble generating tube 31A~34A, 31C~34C, 31D~34D Discharge hole 31G1~34G1, 31G2~34G2 Discharge hole group 41, 42 Liquid discharge pipe 51, 52 First gas supply pipe 53, 54 Second gas supply pipe 71, 72 Liquid supply pipe L Treatment solution LS liquid level W board WS Main surface

Claims

1. A substrate holding section that holds at least one substrate, A treatment tank for storing a treatment liquid for immersing the substrate held in the substrate holding section, The system includes a plurality of bubble generating tubes that generate bubbles in the processing liquid by supplying gas to the processing liquid, Each of the aforementioned plurality of bubble generating tubes has a plurality of discharge holes for discharging the gas, The substrate processing apparatus comprises, in which the plurality of discharge holes include at least a first discharge hole having a first diameter and a second discharge hole having a second diameter larger than the first diameter.

2. The first discharge hole is formed in the inner bubble generating tube, which is located below the central region of the substrate immersed in the processing liquid, among the plurality of bubble generating tubes. The substrate processing apparatus according to claim 1, wherein the second discharge hole is formed in the outer bubble generating tube located below the outer peripheral region of the substrate immersed in the processing liquid, among the plurality of bubble generating tubes.

3. A first gas supply pipe connecting the gas supply source and the outer bubble generating pipe, A second gas supply pipe connecting the gas supply source and the inner bubble generating pipe, Multiple liquid discharge pipes that discharge the processing liquid into the processing tank, thereby generating an upflow that flows upward inside the processing tank, The system comprises a first flow rate control mechanism for controlling the flow rate of gas flowing through the first gas supply pipe and the second gas supply pipe, The outer bubble generating tube, the inner bubble generating tube, and the plurality of liquid discharge tubes extend in the direction normal to the main surface of the substrate. In the view from the normal direction, The plurality of liquid discharge pipes are arranged between the outer bubble generating pipe and the inner bubble generating pipe, The upflow generated by the plurality of liquid discharge pipes generates a downward flow along the side of the treatment tank after reaching the liquid surface of the treatment liquid in the treatment tank. The substrate processing apparatus according to claim 2, wherein the first flow rate control mechanism controls the flow rate of gas supplied to the first gas supply pipe so that the bubbles generated in the outer bubble generating pipe rise against the downward flow.

4. In at least one of the plurality of bubble generating tubes, the first discharge hole and the second discharge hole are formed along a predetermined arrangement direction. The substrate processing apparatus according to claim 1, wherein the predetermined arrangement direction is the direction in which the substrate holding portion holds the plurality of substrates such that the main surfaces of the plurality of adjacent substrates face each other with a gap between them.

5. In at least one of the plurality of bubble generating tubes, a first discharge hole group consisting of a plurality of first discharge holes continuous along a predetermined arrangement direction and a second discharge hole group consisting of a plurality of second discharge holes continuous along the arrangement direction are formed. The substrate processing apparatus according to claim 1, wherein the predetermined arrangement direction is the direction in which the substrate holding portion holds the plurality of substrates such that the main surfaces of the plurality of adjacent substrates face each other with a gap between them.

6. The substrate holding portion includes a mounting portion for placing the plurality of substrates, and a back plate positioned at one end of the mounting portion and extending vertically along the side wall of the processing tank. The substrate processing apparatus according to claim 4 or 5, wherein the second discharge hole is formed on a side further away from the back plate than the first discharge hole.

7. The substrate processing apparatus according to claim 1, wherein the processing solution includes a phosphoric acid solution.

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