Substrate processing equipment

Abstract

To provide a substrate processing apparatus capable of improving a removal ratio of a contaminant in a peripheral region of a substrate.SOLUTION: A substrate processing apparatus comprises: a mounting stage which can rotate a substrate; a liquid supply part that can supply liquid to a surface opposite to the mounting state side of the substrate; and a cooling nozzle that is provided at an inner part of a hole which penetrates the mounting state in a thickness direction, and can supply a cooling gas to a space between the mounting stage and the substrate. An end surface of the cooling nozzle on the substrate side is positioned at a side closer to the substrate side than a surface of the substrate side of the mounting stage. In the case where a planar surface shape of the substrate is a regular square, a dimension of the end surface of the cooling nozzle is 1 / 4 or more of the length of one side of the substrate. In the case where the planar surface shape of the substrate is a circle, the dimension of the end surface of the cooling nozzle is 1 / 4 or more of a diameter of the substrate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a substrate processing apparatus.

Background Art

[0002] As a method for removing contaminants such as particles adhering to the surface of a substrate such as an imprint template, a photolithography mask, or a semiconductor wafer, a freeze cleaning method has been proposed.

[0003] In a general freeze cleaning method, first, a substrate is placed on a mounting table. At this time, the surface of the substrate on the side where freeze cleaning is to be performed (for example, the surface on which concave and convex portions as patterns are formed) is directed upward in the gravitational direction. Next, for example, pure water is supplied to the surface of the rotated substrate on the side where freeze cleaning is to be performed (hereinafter simply referred to as the cleaning surface). Next, the supply of pure water is stopped, and a part of the supplied pure water is discharged to form a water film on the cleaning surface of the substrate. Next, a cooling gas is supplied to the water film to form an ice film. When the water film freezes and the ice film is formed, contaminants such as particles are incorporated into the ice film, so that the contaminants are separated from the cleaning surface of the substrate. Next, pure water is supplied to the ice film to melt the ice film, and the contaminants are removed from the cleaning surface of the substrate together with the pure water. (For example, refer to Patent Document 1) If a substrate processing apparatus capable of performing the freeze cleaning method is used, contaminants can be efficiently removed from the cleaning surface of the substrate. However, in a substrate processing apparatus capable of performing the freeze cleaning method, there has been room for improvement in improving the removal rate of contaminants in the peripheral region of the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem that this invention aims to solve is to provide a substrate processing apparatus that can improve the removal rate of contaminants in the peripheral region of the substrate. [Means for solving the problem]

[0006] The substrate processing apparatus according to the embodiment includes a mounting table on which the substrate can be rotated, a liquid supply unit capable of supplying liquid to the side of the substrate opposite to the mounting table, and a hole that penetrates the mounting table in the thickness direction. , leaving a gap between the inner wall of the hole and Established A cooling nozzle , the above Cooling nozzle The device includes a cooling nozzle capable of supplying cooling gas to the space between the substrate and the device. The mounting base is provided such that the surface facing the substrate is outside the substrate-side end face of the cooling nozzle, forming a space between it and the substrate and facing the substrate. The cooling nozzle the aforementioned end The surface is located closer to the substrate than the surface of the stand described above that is on the substrate side. If the planar shape of the substrate is square, the dimension of the end face of the cooling nozzle is 1 / 4 or more of the length of one side of the substrate. . before If the planar shape of the substrate is circular, the dimension of the end face of the cooling nozzle is at least 1 / 4 of the diameter of the substrate. [Effects of the Invention]

[0007] According to embodiments of the present invention, a substrate processing apparatus is provided that can improve the removal rate of contaminants in the peripheral region of the substrate. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram illustrating the substrate processing apparatus according to this embodiment. [Figure 2] Figure 1 is a schematic diagram of the substrate processing apparatus as viewed from the direction of line AA. [Figure 3] This graph illustrates the relationship between the position of the end face of the cooling nozzle and the rate of contaminant removal. [Figure 4] This is a schematic diagram illustrating the holes in a mounting base according to another embodiment. [Figure 5](a) is a schematic side view illustrating the dimensions of the end face of a cooling nozzle according to another embodiment. (b) is a schematic view of the mounting portion and cooling nozzle in (a) as seen from the direction of line BB. [Figure 6] This is a schematic diagram illustrating the end face of a cooling nozzle according to another embodiment. [Figure 7] This is a schematic diagram illustrating the end face of a cooling nozzle according to another embodiment. [Figure 8] This is a schematic diagram illustrating a mounting base and cooling nozzle according to another embodiment. [Figure 9] This is a schematic diagram illustrating a mounting base and cooling nozzle according to another embodiment. [Modes for carrying out the invention]

[0009] The embodiments will be illustrated below with reference to the drawings. In each drawing, similar components are denoted by the same reference numerals, and detailed descriptions will be omitted as appropriate. The substrate 100 exemplified below can be, for example, a semiconductor wafer, an imprint template, a photolithography mask, or a plate-like body used in MEMS (Micro Electro Mechanical Systems).

[0010] The cleaned surface of the substrate 100 may or may not have a pattern of raised and recessed areas. A substrate without raised and recessed areas can be, for example, a substrate before the formation of raised and recessed areas (for example, a so-called bulk substrate).

[0011] Furthermore, in the following section, we will describe the case where the substrate 100 is a photolithography mask as an example. When the substrate 100 is a photolithography mask, the planar shape of the substrate 100 can be, for example, a square.

[0012] Figure 1 is a schematic diagram illustrating a substrate processing apparatus 1 according to this embodiment. FIG. 2 is a schematic view of the substrate processing apparatus 1 in FIG. 1 when viewed in the direction of line A-A. As shown in FIGS. 1 and 2, the substrate processing apparatus 1 is provided with, for example, a mounting unit 2, a cooling unit 3, a liquid supply unit 4, a chamber 5, an exhaust unit 6, and a controller 7.

[0013] The mounting unit 2 rotates the mounted substrate 100. The mounting unit 2 has, for example, a mounting table 2a, support pins 2b, and a driving unit 2c. The mounting table 2a is rotatably provided inside the chamber 5. The mounting table 2a has a plate shape. For example, as shown in FIG. 2, the mounting table 2a can be a disk. A hole 2a1 penetrating the mounting table 2a in the thickness direction is provided in the central region of the mounting table 2a. The hole 2a1 is provided coaxially with the mounting table 2a. In the present embodiment, the thickness direction is the same direction as the height direction of the mounting table 2a (the direction along the rotation axis of the mounting table 2a).

[0014] A plurality of support pins 2b for supporting the substrate 100 are provided on the upper surface 2a3 of the mounting table 2a. The plurality of support pins 2b are provided around the hole 2a1. When the substrate 100 is supported by the plurality of support pins 2b, the cleaning surface 100b (the surface on the side where cryogenic cleaning is performed) of the substrate 100 faces the side opposite to the mounting table 2a side. That is, the mounting unit 2 supports the substrate 100 such that the cleaning surface 100b of the substrate 100 faces the upper side in the gravitational direction.

[0015] The tips 2b1 of the multiple support pins 2b are in contact with the edges of the surface 100a of the substrate 100 opposite to the cleaning surface 100b (hereinafter simply referred to as the back surface 100a). As shown in Figure 1, the tips 2b1 of the multiple support pins 2b are provided with tapered or inclined surfaces. The tip 2b1 of the support pin 2b exemplified in Figure 1 is provided with a tapered surface. Therefore, the edge of the back surface 100a of the substrate 100 comes into contact with the tapered or inclined surface of the tip 2b1. If the part of the support pin 2b that comes into contact with the edge of the back surface 100a of the substrate 100 is a tapered surface, the support pin 2b and the edge of the back surface 100a of the substrate 100 make point contact. If the part of the support pin 2b that comes into contact with the edge of the back surface 100a of the substrate 100 is an inclined surface, the support pin 2b and the edge of the back surface 100a of the substrate 100 make line contact. Therefore, it is possible to suppress the occurrence of dirt, damage, etc. on the back surface 100a of the substrate 100.

[0016] A rotating shaft (not shown) is provided on the side of the mounting base 2a opposite to the side where the multiple support pins 2b are located. The end of the rotating shaft opposite to the mounting base 2a is located outside the chamber 5. The drive unit 2c is located outside the chamber 5 and rotates the mounting base 2a via the rotating shaft. The drive unit 2c has a rotating device such as a motor. In addition to starting and stopping the rotation, the drive unit 2c can also change the rotation speed and direction of rotation. In this case, the drive unit 2c can be equipped with a control motor such as a servo motor.

[0017] The cooling unit 3 directly supplies cooling gas 3a1 to the back surface 100a of the substrate 100 from the downward side in the direction of gravity. The cooling unit 3 includes, for example, a coolant section 3a, a filter 3b, a flow rate control unit 3c, and a cooling nozzle 3d. The coolant section 3a, filter 3b, and flow rate control unit 3c are located outside the chamber 5. The cooling nozzle 3d is located inside the chamber 5.

[0018] The coolant section 3a, for example, stores the coolant and generates the cooling gas 3a1. The coolant is a liquefied form of the cooling gas 3a1. The cooling gas 3a1 is not particularly limited as long as it is a gas that does not react easily with the material of the substrate 100. The cooling gas 3a1 can be an inert gas such as nitrogen gas, helium gas, or argon gas.

[0019] In this case, using a gas with a high specific heat can shorten the cooling time of the substrate 100. For example, using helium gas can shorten the cooling time of the substrate 100. Also, using nitrogen gas can reduce the processing cost of the substrate 100.

[0020] The coolant section 3a includes a tank for storing coolant and a vaporization section for vaporizing the coolant stored in the tank. The tank is equipped with a cooling device for maintaining the temperature of the coolant. The vaporization section raises the temperature of the coolant to generate cooling gas 3a1 from the coolant. The vaporization section can, for example, utilize the ambient temperature or use heating with a heat transfer medium. The temperature of the cooling gas 3a1 should be below the freezing point of the liquid 101 supplied to the cleaning surface 100b of the substrate 100. The temperature of the cooling gas 3a1 can be, for example, -170°C.

[0021] Filter 3b is connected to the coolant section 3a via piping. Filter 3b prevents contaminants such as particles contained in the coolant from flowing out to the substrate 100 side.

[0022] The flow control unit 3c is connected to the filter 3b via piping. The flow control unit 3c controls the flow rate of the cooling gas 3a1. The flow control unit 3c can be, for example, an MFC (Mass Flow Controller). Alternatively, the flow control unit 3c may indirectly control the flow rate of the cooling gas 3a1 by controlling the supply pressure of the cooling gas 3a1. In this case, the flow control unit 3c can be, for example, an APC (Auto Pressure Controller).

[0023] In the coolant section 3a, the temperature of the cooling gas 3a1 generated from the coolant is approximately at a predetermined temperature. Therefore, the flow rate control unit 3c can control the flow rate of the cooling gas 3a1, thereby controlling the temperature of the substrate 100 and, consequently, the temperature of the liquid 101 on the cleaning surface 100b of the substrate 100.

[0024] The cooling nozzle 3d is located on the lower side of the substrate 100 in the direction of gravity. The cooling nozzle 3d supplies cooling gas 3a1 to the space between the mounting base 2a and the substrate 100. The cooling nozzle 3d is located inside the hole 2a1 of the mounting base 2a. The cooling nozzle 3d is located coaxially with the hole 2a1 of the mounting base 2a. The cooling nozzle 3d has a hole 3d2 that penetrates the cooling nozzle 3d in the direction of its central axis. The hole 3d2 is located coaxially with the cooling nozzle 3d. The hole 3d2 serves as the supply hole (nozzle hole) for the cooling gas 3a1.

[0025] One end face 3d1 of the cooling nozzle 3d faces the back surface 100a of the substrate 100. The end face 3d1 of the cooling nozzle 3d is approximately parallel to the surface 2a3 of the mounting base 2a on which the multiple support pins 2b are provided. When the substrate 100 is supported by the multiple support pins 2b, the back surface 100a of the substrate 100 becomes approximately parallel to the surface 2a3 of the mounting base 2a on which the multiple support pins 2b are provided. Therefore, the end face 3d1 of the cooling nozzle 3d becomes approximately parallel to the back surface 100a of the substrate 100. As a result, a flow path for cooling gas 3a1 with approximately constant dimensions is formed between the end face 3d1 of the cooling nozzle 3d and the back surface 100a of the substrate 100.

[0026] The cooling nozzle 3d can be fixed inside the chamber 5. As mentioned above, the mounting base 2a rotates, so a gap 2a2 is provided between the cooling nozzle 3d fixed inside the chamber 5 and the inner wall of the hole 2a1 in the mounting base 2a. Providing a gap 2a2 simplifies the sealing structure at the connection point of the cooling nozzle 3d to the flow control unit 3c. This improves the reliability of the cooling gas 3a1 supply and reduces the manufacturing cost of the substrate processing apparatus 1.

[0027] Further details regarding the dimensions of the end face 3d1 of the cooling nozzle 3d, as well as the position of the end face 3d1, will be described later.

[0028] The liquid supply unit 4 supplies liquid 101 to the cleaning surface 100b of the substrate 100. The liquid 101 supplied to the cleaning surface 100b of the substrate 100 is cooled by the cooling gas 3a1 supplied to the back surface 100a of the substrate 100. When the liquid 101 freezes, its volume changes, generating a pressure wave. It is believed that this pressure wave separates contaminants adhering to the cleaning surface 100b of the substrate 100. Therefore, there are no particular limitations on the liquid 101 as long as it does not react easily with the material of the substrate 100.

[0029] In this case, if liquid 101 is a liquid that increases in volume when frozen, it is conceivable that contaminants adhering to the cleaning surface 100b of the substrate 100 can be separated by utilizing the physical force associated with the volume increase. Therefore, it is preferable that liquid 101 is a liquid that does not react easily with the material of the substrate 100 and increases in volume when frozen. For example, liquid 101 can be water (e.g., pure water or ultrapure water) or a liquid mainly composed of water. A liquid mainly composed of water can be, for example, a mixture of water and alcohol, a mixture of water and an acidic solution, or a mixture of water and an alkaline solution. In addition, a gas can be dissolved in liquid 101. The gas can be, for example, carbon dioxide, ozone, or hydrogen gas.

[0030] The liquid supply unit 4 includes, for example, a liquid storage unit 4a, a supply unit 4b, a flow rate control unit 4c, and a liquid nozzle 4d. The liquid storage unit 4a, the supply unit 4b, and the flow rate control unit 4c are located outside the chamber 5. The liquid nozzle 4d is located inside the chamber 5.

[0031] The liquid storage section 4a stores the liquid 101. The liquid 101 is stored in the liquid storage section 4a at a temperature higher than its freezing point. For example, the liquid 101 is stored at room temperature (20°C).

[0032] The supply unit 4b is connected to the liquid storage unit 4a via piping. The supply unit 4b supplies the liquid 101 stored in the liquid storage unit 4a towards the liquid nozzle 4d. The supply unit 4b can be, for example, a pump resistant to the liquid 101. Although the example given is that the supply unit 4b is a pump, the supply unit 4b is not limited to a pump. For example, the supply unit 4b may supply gas into the liquid storage unit 4a and pressurize the liquid 101 stored in the liquid storage unit 4a.

[0033] The flow control unit 4c is connected to the supply unit 4b via piping. The flow control unit 4c controls the flow rate of the liquid 101 supplied by the supply unit 4b. The flow control unit 4c can be, for example, a flow control valve. The flow control unit 4c can also start and stop the supply of the liquid 101.

[0034] The liquid nozzle 4d is located on the upper side of the substrate 100 in the direction of gravity. One end of the liquid nozzle 4d is connected to the flow control unit 4c via piping. The other end of the liquid nozzle 4d (the outlet for the liquid 101) faces the cleaning surface 100b of the substrate 100, which is placed on the mounting base 2a. The other end of the liquid nozzle 4d is located approximately in the center of the cleaning surface 100b of the substrate 100.

[0035] The liquid 101 discharged from the liquid nozzle 4d is supplied to the cleaning surface 100b of the substrate 100. As the substrate 100 rotates, the liquid 101 supplied to the cleaning surface 100b of the substrate 100 spreads toward the periphery of the substrate 100. As a result, a film of liquid 101 with approximately constant thickness is formed on the cleaning surface 100b of the substrate 100. Hereafter, the film of liquid 101 formed on the cleaning surface 100b of the substrate 100 will be referred to as the liquid film 101a.

[0036] Chamber 5 is box-shaped. Chamber 5 has an airtight structure that can prevent particles and other contaminants from entering from the outside. Multiple outlets 5a are provided on the side of the bottom surface of Chamber 5. In the case of Chamber 5 illustrated in Figure 1, there are two outlets 5a. Used cooling gas 3a1 and liquid 101 are discharged to the outside of Chamber 5 through the outlets 5a.

[0037] The exhaust port 5a is located below the substrate 100. As a result, a downflow is formed when the cooling gas 3a1 is exhausted from the exhaust port 5a. This prevents particles from being stirred up. In addition, in a plan view, the multiple exhaust ports 5a are arranged symmetrically with respect to the center of the chamber 5. In this way, the exhaust direction of the cooling gas 3a1 is symmetrical with respect to the center of the chamber 5. If the exhaust direction of the cooling gas 3a1 is symmetrical, the exhaust of the cooling gas 3a1 will be smooth.

[0038] The exhaust unit 6 is connected to the outlet 5a via the exhaust pipe 6a. The exhaust unit 6 discharges the used cooling gas 3a1 to the outside of the chamber 5. The exhaust unit 6 can be, for example, a pump or a blower. The used liquid 101 is discharged to the outside of the chamber 5 via the discharge pipe 6a1 connected to the exhaust pipe 6a.

[0039] In addition, an air supply unit for supplying air to the inside of the chamber 5, a detection unit, and other components can be provided as appropriate. The detection unit detects, for example, the temperature of the liquid film 101a, the temperature of the film in which the liquid 101 and the frozen liquid 101 are mixed, and the temperature of the frozen liquid 101 (frozen film).

[0040] The controller 7 controls the operation of each element provided in the substrate processing apparatus 1. For example, the controller 7 can control the rotation of the substrate 100, the supply of cooling gas 3a1, and the supply of liquid 101. The controller 7 has, for example, an arithmetic unit such as a CPU (Central Processing Unit) and a storage unit such as semiconductor memory. The controller 7 is, for example, a computer. The storage unit can store control programs that control the operation of each element provided in the substrate processing apparatus 1. The arithmetic unit controls the operation of each element provided in the substrate processing apparatus 1 using the control programs stored in the storage unit and data input by the operator.

[0041] For example, the controller 7 controls the operation of each element provided in the substrate processing apparatus 1 to sequentially execute the preliminary process, the liquid film 101a formation process, the cooling process, the thawing process, and the drying process.

[0042] In the preliminary step, the controller 7 controls the supply unit 4b and the flow rate control unit 4c to supply liquid 101 at a predetermined flow rate to the cleaning surface 100b of the substrate 100. The controller 7 also controls the flow rate control unit 3c to supply cooling gas 3a1 at a predetermined flow rate to the back surface 100a of the substrate 100. The supply of cooling gas 3a1 at a predetermined flow rate is carried out continuously, for example, throughout the preliminary step, the liquid film 101a formation step, and the cooling step. The controller 7 also controls the drive unit 2c to rotate the substrate 100 at a predetermined rotational speed.

[0043] In the liquid film 101a formation process, the controller 7 controls the supply unit 4b and the drive unit 2c to ensure that a liquid film 101a having a predetermined thickness is formed.

[0044] In the cooling process, the controller 7 controls the drive unit 2c to sequentially execute the "supercooling process," the "freezing process (solid-liquid phase)," and the "freezing process (solid phase)." In the "supercooling process," the cooling gas 3a1 continuously supplied to the back surface 100a of the substrate 100 causes the temperature of the liquid film 101a formed on the cleaned surface 100b to drop even further than the temperature of the liquid film 101a during the liquid film 101a formation process, resulting in a supercooled state.

[0045] When the supercooled liquid film 101a begins to freeze, the process transitions from the "supercooling process" to the "freezing process (solid-liquid phase)". In the "freezing process (solid-liquid phase)", the liquid 101 and the frozen liquid 101 are present across the entire cleaning surface 100b of the substrate 100. When the liquid film 101a on the cleaning surface 100b of the substrate 100 is completely frozen, the process transitions from the "freezing process (solid-liquid phase)" to the "freezing process (solid phase)". In the "freezing process (solid phase)", only the frozen liquid 101 is present on the cleaning surface 100b of the substrate 100.

[0046] As mentioned above, it is thought that contaminants adhering to the cleaning surface 100b of the substrate 100 will be separated from the cleaning surface 100b by the pressure waves and physical forces generated when the liquid 101 freezes. Therefore, in the "freezing process (solid-liquid phase)" and the "freezing process (solid phase)," the contaminants are separated from the cleaning surface 100b.

[0047] In the thawing process, the controller 7 controls the supply unit 4b and the flow rate control unit 4c to supply liquid 101 to the film of frozen liquid 101 on the cleaning surface 100b of the substrate 100. The controller 7 also controls the flow rate control unit 3c to stop the supply of cooling gas 3a1. The controller 7 also controls the drive unit 2c to increase the rotation speed of the substrate 100. Liquid 101, frozen liquid 101, and contaminants separated from the cleaning surface 100b of the substrate 100 are discharged from the cleaning surface 100b of the substrate 100 by centrifugal force.

[0048] During the drying process, the controller 7 controls the supply unit 4b and the flow rate control unit 4c to stop the supply of liquid 101. The controller 7 can also control the drive unit 2c to further increase the rotation speed of the substrate 100. A faster rotation speed allows for faster drying of the substrate 100. The rotation speed of the substrate 100 is not particularly limited as long as drying is possible.

[0049] By following the above procedure, a single freeze-cleaning process can be performed. Note that the freeze-cleaning process can also be performed multiple times. When performing the freeze-cleaning process multiple times, the drying step in the currently running freeze-cleaning process can be omitted.

[0050] Next, we will further explain the dimensions of the end face 3d1 of the cooling nozzle 3d and the position of the end face 3d1. Cooling nozzles in typical substrate processing equipment capable of freeze-cleaning have dimensions in the direction perpendicular to the central axis that are smaller than those of the mounting table 2a. Furthermore, the thickness of the cooling nozzles is also thin. Cooling gas 3a1 supplied from such a narrow cooling nozzle to the central region of the back surface 100a of the substrate 100 immediately diffuses within the space between the substrate 100 and the mounting table after reaching the central region. If a gap 2a2 is provided between the cooling nozzle and the inner wall of the hole 2a1 in the mounting table 2a, some of the cooling gas flows into the gap 2a2 between the cooling nozzle and the mounting table 2a. Therefore, as the substrate 100 approaches its periphery, the flow velocity of the cooling gas 3a1 decreases, and the amount of cooling gas 3a1 in contact with the back surface 100a of the substrate 100 decreases.

[0051] If the flow rate of the cooling gas 3a1 slows down, or if the amount of cooling gas 3a1 in contact with the back surface 100a of the substrate 100 decreases, it may become difficult to lower the temperature in the peripheral region of the cleaning surface 100b of the substrate 100 to a predetermined temperature. As mentioned above, contaminants are separated from the cleaning surface 100b during the "freezing process (solid-liquid phase)" and the "freezing process (solid phase)". Therefore, if the temperature in the peripheral region of the cleaning surface 100b of the substrate 100 cannot be lowered to a predetermined temperature, the removal rate of contaminants in the peripheral region of the cleaning surface 100b of the substrate 100 may be low. As shown in Figure 2, if the planar shape of the substrate 100 is a rectangle such as a square, the distance between the center of the substrate 100 and the corners of the substrate 100 is longer than the distance between the center of the substrate 100 and the sides of the substrate 100, so the removal rate of contaminants near the corners of the substrate 100 may be even lower.

[0052] Therefore, in the cooling nozzle 3d according to this embodiment, the dimension of the end face 3d1 of the cooling nozzle 3d on the substrate 100 side is made larger than the dimension of the end face of a cooling nozzle provided in a general substrate processing apparatus. As mentioned above, the space between the end face 3d1 of the cooling nozzle 3d and the back surface 100a of the substrate 100 becomes a flow path for the cooling gas 3a1. Therefore, if the dimension of the end face 3d1 is large, the cooling gas 3a1 supplied to this space will diffuse in a direction parallel to the end face 3d1 of the cooling nozzle 3d, but diffusion in a direction perpendicular to the end face 3d1 of the cooling nozzle 3d will be prevented. Consequently, it is possible to suppress the slowing of the flow velocity of the cooling gas 3a1 and the reduction in the amount of cooling gas 3a1 in contact with the back surface 100a of the substrate 100. As a result, it becomes easier to lower the temperature in the peripheral region of the cleaning surface 100b of the substrate 100 to a predetermined temperature. If the temperature in the peripheral region of the cleaning surface 100b of the substrate 100 can be reduced to a predetermined temperature, the removal rate of contaminants in the peripheral region of the cleaning surface 100b of the substrate 100 can be improved. In other words, the removal rate of contaminants across the entire area of ​​the cleaning surface 100b of the substrate 100 can be improved.

[0053] Furthermore, it is preferable that the distance from the outer edge of hole 3d2 to the outer edge of end face 3d1 (hereinafter referred to as the width of end face 3d1) be wide. Since the cooling nozzle 3d does not rotate, the cooling gas flowing between the substrate 100 and the end face 3d1 is agitated by its relative movement with the rotating substrate. If the width of end face 3d1 is wide, the amount of agitated cooling gas increases. Therefore, if a nozzle with a narrow end face 3d1 is used, there is a risk of uneven distribution of the cooling gas flow spreading toward the outer circumference of the substrate 100. However, even in such cases, if the width of end face 3d1 is wide, it is possible to suppress the occurrence of uneven distribution of the cooling gas flow due to agitation.

[0054] Furthermore, it is preferable that the size of the hole 3d2 in the cooling nozzle 3d1 be φ35 mm or less. When discharging cooling gas at the same supply rate (supply pressure), the larger the diameter of the hole 3d2, the more cooling gas is required. Also, when discharging cooling gas at the same supply rate (supply pressure), the larger the diameter of the hole 3d2, the greater the pressure applied to the substrate 100. As a result, there is a risk that the substrate 100 may be blown away. Therefore, even if the diameter of the hole 3d2 is increased, the supply rate of cooling gas must be reduced. Reducing the supply rate of cooling gas may cause uneven distribution of the cooling gas flow that spreads toward the outer circumference of the substrate 100. As a result, there is a risk that the removal rate of contaminants within the plane of the substrate 100 may vary. For this reason, it is preferable that the size of the hole 3d2 be φ35 mm or less. More preferably, it should be φ10 mm or more and φ30 mm or less.

[0055] According to the inventors' findings, when the dimension of the end face 3d1 of the cooling nozzle 3d is D (mm) and the length of one side of the square substrate 100 is L (mm), setting "D ≥ L / 4" improves the removal rate of contaminants in the peripheral region of the cleaning surface 100b of the substrate 100. The width of the gap 2a2 is preferably as narrow as possible, for example, about 1 mm to 10 mm. In this case, the larger D (mm) is, the better the removal rate of contaminants in the peripheral region of the cleaning surface 100b of the substrate 100.

[0056] This is likely because the amount of cooling gas contributing to the cooling of the substrate 100 increases. As mentioned above, some of the cooling gas flows into the gap 2a2. Increasing D (mm) also increases the diameter of the gap 2a2. As a result, the cooling gas flows into the gap 2a2 in the peripheral region of the substrate 100. In this case, the cooling gas that has diffused to the peripheral region of the substrate 100 is at a higher temperature than the cooling gas present in the central region of the substrate 100. This is mainly because heat is supplied from the substrate 100 (more precisely, heat is also supplied from the cooling nozzle 3d and the mounting base 2a, but this is less than that from the substrate 100, so it is ignored). Therefore, the cooling capacity of the cooling gas that has diffused to the peripheral region of the substrate 100 is reduced. On the other hand, the cooling gas present in the central region of the substrate 100 is at almost the same temperature as when it was discharged from the cooling gas nozzle 3d. In other words, the cooling capacity of the cooling gas present in the central region of the substrate 100 is not reduced. When the cooling gas present in the central region of the substrate 100, which was flowing into the gap 2a2, begins to flow towards the peripheral region of the substrate 100, the amount of cooling gas cooling the peripheral region of the substrate 100 increases. Therefore, the substrate 100 can be cooled more effectively when the cooling gas present in the peripheral region of the substrate 100 flows into the gap 2a2 than when the cooling gas present in the central region of the substrate 100 flows into the gap 2a2.

[0057] For example, as shown in Figure 2, setting "D=L" significantly improves the removal rate of contaminants in the peripheral region of the cleaning surface 100b of the substrate 100. In this case, cooling gas is generated that flows into the gap 2a2 after exceeding the space between the substrate 100 and the mounting base 2a. Therefore, the amount of cooling gas contributing to the cooling of the substrate 100 increases, resulting in a significant improvement. For this reason, when the planar shape of the substrate 100 is square, it is preferable that the dimension of the end face 3d1 of the cooling nozzle 3d be L / 4 ≤ D ≤ L. Within the aforementioned range, it is more preferable that D is closer to L.

[0058] The above applies to a substrate 100 with a square planar shape, but the same applies to a substrate with a circular planar shape (e.g., a semiconductor wafer). For example, in the case of a substrate with a circular planar shape, D (mm) should be set to be 1 / 4 or more of the diameter of the substrate. In this case, if D (mm) is the same as the diameter of the substrate, the removal rate of contaminants in the peripheral region of the cleaning surface of a substrate with a circular planar shape will be about the same as the removal rate of contaminants in the central region of the cleaning surface of the substrate. Therefore, in the case of a substrate with a circular planar shape, it is preferable that the dimension of the end face 3d1 of the cooling nozzle 3d be L / 4 ≤ D ≤ L.

[0059] Here, in the direction of the central axis of the cooling nozzle 3d, the end face 3d1 of the cooling nozzle 3d may be flush with the surface 2a3 of the mounting base 2a on which the multiple support pins 2b are provided, or the end face 3d1 of the cooling nozzle 3d may be located on the opposite side of surface 2a3 from the substrate 100 side. However, in this case, the cooling gas 3a1 that has flowed through the space between the end face 3d1 of the cooling nozzle 3d and the back surface 100a of the substrate 100 is more likely to enter the gap 2a2 when it flows out to the outside of the end face 3d1 of the cooling nozzle 3d. If the cooling gas 3a1 enters the gap 2a2, the liquid 101 that has entered the gap 2a2 is more likely to freeze, or the components provided below the mounting base 2a are more likely to freeze. If the liquid 101 freezes in the gap 2a2, the rotation of the mounting base 2a may be hindered. If the components provided below the mounting base 2a freeze, it may cause a malfunction.

[0060] Therefore, as shown in FIG. 1, in the cooling nozzle 3d according to the present embodiment, in the direction of the central axis of the cooling nozzle 3d, the end face 3d1 of the cooling nozzle 3d is located closer to the substrate 100 than the surface 2a3 of the mounting table 2a. According to the findings obtained by the present inventors, in the direction of the central axis of the cooling nozzle 3d, when the distance between the surface 2a3 of the mounting table 2a and the back surface 100a of the substrate 100 is H (mm), and the distance between the end face 3d1 of the cooling nozzle 3d and the back surface 100a of the substrate 100 is H1 (mm), it is preferable that "H1 < H". More preferably, "H1 ≤ H / 2". By doing so, when the cooling gas 3a1 flowing through the space between the end face 3d1 of the cooling nozzle 3d and the back surface 100a of the substrate 100 flows out to the outside of the end face 3d1 of the cooling nozzle 3d, it becomes difficult to penetrate into the gap 2a2. Also, by doing so, the flow rate of the cooling gas 3a1 can be further increased, or the amount of the cooling gas 3a1 contacting the back surface 100a of the substrate 100 can be further increased. Therefore, the removal rate of contaminants in the peripheral region of the substrate 100 can be further improved.

[0061] FIG. 3 is a graph for exemplifying the relationship between the position of the end face 3d1 of the cooling nozzle 3d and the removal rate of contaminants. The removal rate of contaminants is calculated by obtaining the number of contaminants adhering to the cleaning surface 100b of the substrate 100 before the cleaning process and the number of contaminants adhering to the cleaning surface 100b of the substrate 100 after the cleaning process. When all contaminants are removed after the cleaning process, the removal rate becomes 100%. Also, FIG. 3 shows the case where the substrate 100 is a 6025 quartz (Qz) substrate (152 mm × 152 mm × 6.35 mm) and the liquid 101 is pure water. The protrusion ratio α (%) in FIG. 3 is "(H1 - H) / H × 100". As can be seen from FIG. 3, if the end face 3d1 of the cooling nozzle 3d protrudes from the surface 2a3 of the mounting table 2a, the removal rate of contaminants in the peripheral region of the substrate 100 can be improved.

[0062] FIG. 4 is a schematic diagram for exemplifying the hole 2a1 of the mounting table 2a according to another embodiment. As shown in Figure 4, if the diameter of the hole 2a1 in the mounting base 2a is D1 (mm) and the length of one side of the square substrate 100 is L (mm), then "D1 ≤ L" can also be set. In this way, when viewed from a direction perpendicular to the cleaning surface 100b of the substrate 100, the cleaning surface 100b and the gap 2a2 can be superimposed. Therefore, when the liquid 101 on the cleaning surface 100b or the frozen liquid 101 is discharged to the outside of the cleaning surface 100b, it becomes difficult for it to penetrate into the gap 2a2. Therefore, the freezing of the liquid 101 in the gap 2a2 can be further suppressed. Note that "D1 ≤ L" is the range in which D ≥ L / 4 can be obtained. Also, as mentioned above, the width of the gap 2a2 should be about 1 mm to 10 mm.

[0063] In Figure 4, the example shown is for a substrate 100 with a square planar shape, but the same applies to substrates with a circular planar shape (for example, semiconductor wafers). For example, in the case of a substrate with a circular planar shape, "D1 ≤ Diameter of the substrate" should be used.

[0064] Figure 5(a) is a schematic side view illustrating the dimensions of the end face 3d1 of the cooling nozzle 3d according to another embodiment. Figure 5(b) is a schematic diagram of the mounting section 2 and cooling nozzle 3d in Figure 5(a) as viewed from the direction of line BB. As shown in Figure 5(b), the dimension D (mm) of the end face 3d1 of the cooling nozzle 3d can be set to be greater than or equal to the length L1 (mm) of the diagonal of the square-shaped substrate 100. This makes it easier to uniformly supply the cooling gas 3a1 to the entire back surface 100a of the substrate 100. Therefore, the removal rate of contaminants in the peripheral region of the substrate 100 can be further improved. However, increasing D will also increase the size of the mounting base 2a. For this reason, D should be set to L1 + a few mm.

[0065] Furthermore, as mentioned above, the multiple support pins 2b are provided on the surface 2a3 of the mounting base 2a. Therefore, if the dimension D (mm) of the end face 3d1 is greater than or equal to the diagonal length L1 (mm) of the substrate 100, an arm 2b2 can be provided between the support pins 2b and the surface 2a3 of the mounting base 2a, as shown in Figures 5(a) and (b). In this case, since the cooling gas flowing into the gap 2a2 is only the gas that has finished cooling the substrate 100, the end face 3d1 of the cooling nozzle 3d does not need to protrude from the surface 2a3 of the mounting base 2a. In other words, the end face 3d1 of the cooling nozzle 3d may be flush with the surface 2a3 of the mounting base 2a. Also, in this case, the liquid 101 supplied to the substrate 100 is more likely to flow into the gap 2a2. Therefore, for example, a cover can be provided on the arm 2b2 of the support pin 2b to prevent the liquid 101 from flowing into the gap 2a2.

[0066] In Figure 5(b), the example shown is for a substrate 100 with a square planar shape, but the same applies to substrates with a circular planar shape (for example, semiconductor wafers). For example, in the case of a substrate with a circular planar shape, "D ≤ Diameter of the substrate" should be used.

[0067] Figure 6 is a schematic diagram illustrating the end face 13d1 of the cooling nozzle 13d according to another embodiment. As shown in Figure 6, the end face 13d1 of the cooling nozzle 13d is provided with a plurality of grooves 13d2. For example, the cooling nozzle 13d can be the same as the cooling nozzle 3d described above, but with a plurality of grooves 13d2 provided on the end face 3d1. The plurality of grooves 13d2 open into the end face 13d1. The plurality of grooves 13d2 extend between the hole 3d2 and the end face 3d1. The plurality of grooves 13d2 extend radially from the center of the cooling nozzle 13d. If a plurality of grooves 13d2 are provided, the flow of cooling gas 3a1 between the hole 3d2 and the periphery of the end face 13d1 can be restricted. Therefore, it is possible to suppress the flow of cooling gas 3a1 in a biased direction in the direction parallel to the end face 13d1. Therefore, it is possible to suppress variations in the removal rate of contaminants in the peripheral region of the substrate 100. In the cooling process, the rotation of the substrate 100 may be stopped. In this case, if multiple grooves 13d2 extend toward the four corners of the substrate 100, the flow of the cooling gas 3a1 can be restricted to the four corners of the substrate 100.

[0068] Figure 7 is a schematic diagram illustrating the end face 23d1 of a cooling nozzle 23d according to another embodiment. As shown in Figure 7, the end face 23d1 of the cooling nozzle 23d can also be an inclined surface. For example, the end face 23d1 can be inclined in a direction away from the substrate 100 as it approaches the center of the cooling nozzle 23d. Alternatively, the end face 23d1 can be a curved surface. In this way, the cooling gas 3a1 flowing inside the hole 3d2 can be dispersed in a direction perpendicular to the central axis of the cooling nozzle 23d. This allows the dispersion to begin at a position further away from the back surface 100a of the substrate 100 compared to the nozzle 3d. Therefore, it is possible to suppress the temperature of the central region of the substrate 100 from becoming excessively low. When forming the end face 23d1 with multiple inclined surfaces, it is preferable that the inclination angle between adjacent inclined surfaces be 3.5° to 4°.

[0069] Figure 8 is a schematic diagram illustrating a mounting base 12a and cooling nozzle 33d according to another embodiment. As shown in Figure 8, in the direction perpendicular to the central axis of the cooling nozzle 33d, the dimension of the cooling nozzle 33d on the side opposite to the end face 3d1 can be smaller than the dimension of the cooling nozzle 33d on the end face 3d1 side. That is, the cooling nozzle 33d has a stepped structure. The distance (gap 12a2) between the cooling nozzle 33d and the mounting base 12a can be kept approximately constant.

[0070] In this manner, a bent gap 12a2 is formed between the cooling nozzle 33d and the inner wall of the hole 12a1 that penetrates the mounting base 12a in the thickness direction. As a result, the conductance of the gap 12a2 can be reduced. Consequently, the cooling gas 3a1 that flows between the end face 3d1 of the cooling nozzle 33d and the back surface 100a of the substrate 100 can be prevented from flowing inside the gap 12a2.

[0071] Figure 9 is a schematic diagram illustrating a mounting base 22a and cooling nozzle 43d according to another embodiment. As shown in Figure 9, the cooling nozzle 43d can be the aforementioned cooling nozzle 33d with an annular protrusion 43d1 further provided. The protrusion 43d1 can be provided near the end of the cooling nozzle 43d on the substrate 100 side. The protrusion 43d1 faces the end face 3d1 and protrudes in the opposite direction to the end face 3d1. A recess 22a3 is provided on the inner wall of the hole 22a1 of the mounting base 22a at a position facing the protrusion 43d1.

[0072] In this way, the conductance of the gap 22a2 can be further reduced. As a result, the cooling gas 3a1 that flows between the end face 3d1 of the cooling nozzle 43d and the back surface 100a of the substrate 100 can be further suppressed from flowing inside the gap 22a2.

[0073] The embodiments described above are illustrative examples. However, the present invention is not limited to these descriptions. With respect to the embodiments described above, those who are skilled in the art may add, delete, or modify components, or add, omit, or change processes as appropriate, and these are also included within the scope of the present invention as long as they retain the features of the present invention.

[0074] For example, the shape, dimensions, number, and arrangement of each element of the substrate processing apparatus 1 are not limited to those exemplified and can be changed as appropriate. [Explanation of symbols]

[0075] 1 Substrate processing apparatus, 2 Mounting section, 2a Mounting platform, 2a1 Hole, 2a2 Gap, 2a3 Surface, 3 Cooling section, 3a1 Cooling gas, 3d Cooling nozzle, 3d1 End face, 4 Liquid supply section, 100 Substrate, 100a Back surface, 100b Cleaning surface, 101 Liquid

Claims

1. A mounting platform that allows the circuit board to rotate, The substrate has a liquid supply unit capable of supplying liquid to the side opposite to the stand side described above, A cooling nozzle is provided inside a hole that penetrates the mounting base in the thickness direction, with a gap between it and the inner wall of the hole, and a cooling nozzle capable of supplying cooling gas to the space between the cooling nozzle and the substrate. Equipped with, The mounting base is provided such that the surface facing the substrate is outside the substrate-side end face of the cooling nozzle, forming a space between it and the substrate and facing the substrate. The end face of the cooling nozzle is located closer to the substrate than the substrate-side surface of the stand described above. If the planar shape of the substrate is square, the dimension of the end face of the cooling nozzle is 1 / 4 or more of the length of one side of the substrate. A substrate processing apparatus in which, when the planar shape of the substrate is circular, the dimension of the end face of the cooling nozzle is 1 / 4 or more of the diameter of the substrate.

2. If the planar shape of the substrate is square, the dimensions of the end face of the cooling nozzle are less than or equal to the length of one side of the substrate. The substrate processing apparatus according to claim 1, wherein, when the planar shape of the substrate is circular, the dimension of the end face of the cooling nozzle is less than or equal to the diameter of the substrate.

3. If the planar shape of the substrate is square, the dimensions of the end face of the cooling nozzle are greater than or equal to the length of the diagonal of the substrate. The substrate processing apparatus according to claim 1, wherein, when the planar shape of the substrate is circular, the dimension of the end face of the cooling nozzle is greater than or equal to the diameter of the substrate.

4. If the planar shape of the substrate is square, the diameter of the hole that penetrates the mounting base in the thickness direction is less than or equal to the length of one side of the substrate. The substrate processing apparatus according to claim 1, wherein, when the planar shape of the substrate is circular, the diameter of the hole that penetrates the mounting base in the thickness direction is less than or equal to the diameter of the substrate.

5. The substrate processing apparatus according to any one of claims 1 to 4, wherein the distance between the substrate-side end face of the cooling nozzle and the substrate is 1 / 2 or less the distance between the substrate-side surface of the stand described above and the substrate.

6. The substrate processing apparatus according to any one of claims 1 to 5, wherein the end face of the cooling nozzle on the substrate side is provided with a plurality of grooves extending radially from the center of the cooling nozzle.

7. The substrate processing apparatus according to any one of claims 1 to 6, wherein the end face of the cooling nozzle on the substrate side is an inclined surface that slopes away from the substrate as it approaches the center of the cooling nozzle.

8. The substrate processing apparatus according to any one of claims 1 to 7, wherein the gap is provided in a bent shape.

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