Substrate processing apparatus and substrate processing method

Abstract

The invention provides a substrate processing apparatus and a substrate processing method, which can suppress damage of patterns on the surface of a substrate even when vibration is transmitted to liquid on the surface side of the substrate in a thawing process of freezing a film. The substrate processing apparatus forms a frozen film on a surface of a substrate, absorbs foreign matter adhering to the surface of the substrate into the frozen film, thaws the frozen film including the foreign matter, and removes the foreign matter from the surface of the substrate. The substrate processing apparatus includes a liquid supply unit that supplies a liquid to a frozen film including a foreign matter, a vibration unit that faces the frozen film, and a controller that controls the vibration unit. The controller controls the vibration unit to transmit vibration to the liquid film, the liquid film including the liquid supplied to the frozen film and the liquid generated by thawing the frozen film, and the energy of the vibration transmitted to the liquid film is reduced or the vibration is stopped according to the position of the upper surface of the frozen film below the liquid film.

Description

Technical Field

[0001] The invention relates to a substrate processing device and a substrate processing method. Background Art

[0002] As a method for removing foreign matter such as particles attached 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 the freeze cleaning method, pure water is usually used as a cleaning liquid. For example, in the freeze cleaning method, pure water and cooling gas are first supplied to the surface of a rotating substrate. Then, the supply of pure water is stopped, and part of the supplied pure water is discharged to form a water film on the surface of the substrate. The water film is frozen by the supplied cooling gas. When the water film is frozen to form a frozen film, foreign matter such as particles is taken into the frozen film, so that the foreign matter is separated from the surface of the substrate. Then, a thawing process of the frozen film is performed. In the thawing process, pure water is supplied to the frozen film to thaw the frozen film, and the pure water and the foreign matter are discharged to the outside of the substrate by centrifugal force.

[0004] By performing the above-mentioned freezing cleaning method, the removal rate of foreign matter can be improved. However, in recent years, there is a demand for further improving the removal rate of foreign matter. In this case, if vibration is transmitted to the liquid on the surface side of the substrate during the thawing process of the frozen film, it is possible to suppress the foreign matter separated from the surface of the substrate from being attached to the surface of the substrate again. Therefore, it is possible to achieve a further improvement in the removal rate of foreign matter.

[0005] However, since a fine pattern is formed on the surface of the substrate, there is a possibility that the pattern may be damaged if the vibration is simply transmitted to the liquid.

[0006] Therefore, it is desired to develop a substrate processing apparatus and a substrate processing method that can suppress the pattern on the surface of the substrate from being damaged even when vibration is transmitted to the liquid on the surface side of the substrate in the process of thawing the frozen film.

[0007] [Prior art literature]

[0008] [Patent Document]

[0009] Patent Document 1: Japanese Patent Application Publication No. 2018-026436 Summary of the invention

[0010] [Problems to be solved by the invention]

[0011] An object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of suppressing damage to a pattern on the surface of a substrate even when vibration is transmitted to liquid on the surface side of the substrate in a thawing process of a frozen film.

[0012] [Technical means to solve the problem]

[0013] The substrate processing device of this embodiment forms a frozen film on the surface of a substrate, takes foreign matter attached to the surface of the substrate into the frozen film, thaws the frozen film containing the foreign matter, and removes the foreign matter from the surface of the substrate. The substrate processing device includes: a liquid supply unit that supplies liquid to the frozen film containing the foreign matter; a vibration unit opposite to the frozen film; and a controller that controls the vibration unit. The controller controls the vibration unit to transmit vibration to the liquid film, the liquid film including the liquid supplied to the frozen film and the liquid generated by thawing the frozen film, and reduces the energy of the vibration transmitted to the liquid film or stops the vibration according to the position of the upper surface of the frozen film below the liquid film.

[0014] [Effects of the Invention]

[0015] According to an embodiment of the present invention, a substrate processing apparatus and a substrate processing method are provided, which can suppress damage to a pattern on a surface of a substrate even when vibration is transmitted to liquid on a surface side of the substrate in a thawing process of a frozen film. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram showing a substrate processing apparatus according to this embodiment.

[0017] Figure 2 It is a schematic three-dimensional diagram of a vibrating body.

[0018] Figure 3 It is a schematic diagram showing the role and effect of the groove.

[0019] Figure 4 It is a schematic perspective view of a vibrating body according to another embodiment.

[0020] Figure 5 It is a schematic diagram showing the action and effect of a vibrating body.

[0021] Figure 6 It is a schematic perspective view showing a vibrating body according to another embodiment.

[0022] Figure 7 It is a timing chart showing the operation of the substrate processing apparatus.

[0023] Figure 8 It is a graph showing the temperature change of the liquid supplied to the surface of the substrate.

[0024] Fig. 9 (a) to Fig. 9 (c) is a schematic process cross-sectional view showing the thawing process.

[0025] Fig.10(a) to Fig.10 (c) is a schematic cross-sectional view showing the position of the upper surface of the frozen film when the vibration energy is switched or the vibration is stopped.

[0026] Description of Reference Numerals

[0027] 1: Substrate processing equipment

[0028] 3: Cooling section

[0029] 3a1: Cooling gas

[0030] 4: First liquid supply unit

[0031] 5: Second liquid supply unit

[0032] 6: Chamber

[0033] 9: Vibration part

[0034] 10: Detection Department

[0035] 11: Controller

[0036] 91: Vibrating body

[0037] 92: Vibrator

[0038] 92a: Vibration

[0039] 93: Circuit

[0040] 96: Vibrating body

[0041] 97: Vibrating body

[0042] 100: Substrate

[0043] 100a: Back

[0044] 100b: Surface

[0045] 100c: Pattern

[0046] 101: Liquid

[0047] 101a: Frozen Film

[0048] 102: Liquid

[0049] 103: Liquid film

[0050] 300: Foreign matter DETAILED DESCRIPTION

[0051] Hereinafter, the embodiments will be described exemplarily with reference to the accompanying drawings. In addition, in each of the drawings, the same components are denoted by the same reference numerals, and detailed descriptions thereof are appropriately omitted.

[0052] Furthermore, the substrate 100 exemplarily described below may be, for example, a semiconductor wafer, a template for imprinting, a mask for photolithography, a plate-like body for MEMS (micro-electromechanical system), etc. In addition, the substrate 100 is not limited to the exemplified ones. As long as the surface 100b of the substrate 100 is formed with a pattern (for example, a fine concave-convex portion), it will suffice.

[0053] Figure 1 Schematic diagram showing a substrate processing apparatus 1 according to the present embodiment.

[0054] like Figure 1 As shown, the substrate processing apparatus 1 includes, for example, a mounting portion 2, a cooling portion 3, a first liquid supply portion 4, a second liquid supply portion 5, a chamber 6, an exhaust portion 7, an air supply portion 8, a vibrating portion 9, a detection portion 10, and a controller 11.

[0055] The placement section 2 rotates the placed substrate 100. The placement section 2 includes, for example, a placement table 2a, a rotation shaft 2b, and a driving section 2c.

[0056] The stage 2a is rotatably disposed inside the chamber 6. The stage 2a is in the shape of a plate. A plurality of support portions 2a1 for supporting the substrate 100 are disposed on one main surface of the stage 2a. When the substrate 100 is supported on the plurality of support portions 2a1, the surface 100b (the side to be cleaned) of the substrate 100 is directed in the opposite direction to the stage 2a.

[0057] Furthermore, a hole 2aa penetrating the mounting table 2a in the thickness direction is provided in the center portion of the mounting table 2a.

[0058] One end of the rotating shaft 2b is provided on the inner wall of the hole 2aa of the mounting table 2a. The other end of the rotating shaft 2b is provided outside the chamber 6. The rotating shaft 2b is connected to the driving unit 2c outside the chamber 6.

[0059] The rotating shaft 2b is cylindrical. A blowing portion 2b1 is provided at the end of the rotating shaft 2b on the side of the mounting table 2a. The blowing portion 2b1 opens on the surface of the mounting table 2a on which a plurality of supporting portions 2a1 are provided. The end of the opening side of the blowing portion 2b1 is connected to the inner wall of the hole 2aa. The opening of the blowing portion 2b1 is opposite to the back side 100a of the substrate 100 mounted on the mounting table 2a. In a direction perpendicular to the central axis of the rotating shaft 2b, the cross-sectional area of ​​the blowing portion 2b1 gradually increases as it moves toward the side of the mounting table 2a (opening side).

[0060] By providing the blowing portion 2b1, the released cooling gas 3a1 can be supplied to a wider area of ​​the back surface 100a of the substrate 100. In addition, the release rate of the cooling gas 3a1 can be reduced. Therefore, it is possible to prevent the substrate 100 from being partially cooled or the cooling rate of the substrate 100 from being too fast, which makes it difficult for the liquid 101 described later to be in an overcooled state.

[0061] The end of the rotating shaft 2b on the side opposite to the mounting table 2a is provided with a cooling nozzle 3d. A rotating shaft seal (not shown) is provided between the end of the rotating shaft 2b on the side opposite to the mounting table 2a and the cooling nozzle 3d. Therefore, the end of the rotating shaft 2b on the side opposite to the mounting table 2a is sealed to achieve airtightness.

[0062] The driving unit 2c is disposed outside the chamber 6. The driving unit 2c is connected to the rotating shaft 2b. The rotational force of the driving unit 2c is transmitted to the mounting table 2a through the rotating shaft 2b. Therefore, the mounting table 2a and the substrate 100 mounted on the mounting table 2a can be rotated by the driving unit 2c.

[0063] The drive unit 2c can not only start and stop the rotation, but also change the number of rotations (rotation speed). The drive unit 2c can be equipped with a control motor such as a servo motor, for example.

[0064] The cooling unit 3 supplies a cooling gas 3a1 for cooling the liquid 101 on the surface 100b of the substrate 100. The cooling unit 3 supplies the cooling gas 3a1 to the space between the mounting table 2a and the back surface 100a of the substrate 100. The cooling unit 3 includes, for example, a cooling liquid unit 3a, a filter 3b, a flow control unit 3c, and a cooling nozzle 3d. The cooling liquid unit 3a, the filter 3b, and the flow control unit 3c are provided outside the chamber 6.

[0065] The cooling liquid portion 3a is used to store the cooling liquid and generate the cooling gas 3a1. The cooling liquid is obtained by liquefying the cooling gas 3a1. The cooling gas 3a1 is not particularly limited as long as it is a gas that is difficult to react with the material of the substrate 100. The cooling gas 3a1 can be, for example, an inert gas such as nitrogen, helium, or argon.

[0066] The cooling liquid section 3a has a tank for storing the cooling liquid and a vaporization section for vaporizing the cooling liquid stored in the tank. The tank is provided with a cooling device for maintaining the temperature of the cooling liquid. The vaporization section increases the temperature of the cooling liquid and generates cooling gas 3a1 from the cooling liquid. The vaporization section can be heated, for example, by using the outside temperature or by using a heat medium. The temperature of the cooling gas 3a1 can be any temperature lower than the freezing point of the liquid 101, for example, -170°C.

[0067] Alternatively, the cooling gas 3a1 may be generated by cooling an inert gas such as nitrogen using a cooler etc. In this way, the cooling liquid portion can be simplified.

[0068] The filter 3 b is connected to the cooling liquid unit 3 a via a pipe. The filter 3 b prevents foreign matter such as particles contained in the cooling liquid from flowing out to the substrate 100 side.

[0069] The flow control unit 3c is connected to the filter 3b through a pipe. The flow control unit 3c controls the flow of the cooling gas 3a1. The flow control unit 3c may be, for example, a mass flow controller (MFC). In addition, the flow control unit 3c may also be a device that indirectly controls the flow of the cooling gas 3a1 by controlling the supply pressure of the cooling gas 3a1. In this case, the flow control unit 3c may be, for example, an automatic pressure controller (APC).

[0070] The temperature of the cooling gas 3a1 generated from the cooling liquid in the cooling liquid section 3a is maintained at a substantially predetermined temperature. Therefore, by controlling the flow rate of the cooling gas 3a1 by the flow control section 3c, the temperature of the substrate 100 can be controlled, and further the temperature of the liquid 101 on the surface 100b of the substrate 100 can be controlled. In this case, by controlling the flow rate of the cooling gas 3a1 by the flow control section 3c, the liquid 101 can be supercooled in the cooling process described later.

[0071] The cooling nozzle 3d is cylindrical. One end of the cooling nozzle 3d is connected to the flow control unit 3c. The other end of the cooling nozzle 3d is arranged inside the rotating shaft 2b. The other end of the cooling nozzle 3d is located near the end of the blowing portion 2b1 on the opposite side to the mounting table 2a side (opening side).

[0072] The cooling nozzle 3d supplies the cooling gas 3a1 whose flow rate is controlled by the flow rate control unit 3c to the substrate 100. The cooling gas 3a1 discharged from the cooling nozzle 3d is directly supplied to the back surface 100a of the substrate 100 through the blowing unit 2b1.

[0073] When the cooling gas 3a1 is supplied to the back side 100a of the substrate 100, freezing starts from the back side (the surface on the substrate 100 side) of the film of the liquid 101 formed on the surface 100b of the substrate 100. When freezing starts from the back side of the film of the liquid 101, foreign matter attached to the surface 100b of the substrate 100 is more easily separated from the surface 100b of the substrate 100.

[0074] Therefore, the substrate processing apparatus 1 only needs to supply the cooling gas 3a1 at least to the back side 100a of the substrate 100. For example, the substrate processing apparatus 1 may further supply the cooling gas 3a1 to the surface 100b of the substrate 100. When the cooling gas 3a1 is also supplied to the surface 100b of the substrate 100, a cooling nozzle 3d may also be provided on the surface 100b of the substrate 100.

[0075] The first liquid supply unit 4 supplies the liquid 101 to the surface 100b of the substrate 100. The liquid 101 is used in the preparatory process described later and the process of forming a film of the liquid 101. The liquid 101 is not particularly limited as long as it is a liquid that is difficult to react with the material of the substrate 100. For example, the liquid 101 may be water (for example, pure water or ultrapure water), a liquid with water as the main component, a liquid in which a gas is dissolved, and the like.

[0076] The first liquid supply unit 4 includes, for example, a liquid storage unit 4 a , a supply unit 4 b , a flow rate control unit 4 c , and a liquid nozzle 4 d . The liquid storage unit 4 a , the supply unit 4 b , and the flow rate control unit 4 c are provided outside the chamber 6 .

[0077] The liquid storage part 4a stores the liquid 101. The temperature of the liquid 101 stored in the liquid storage part 4a is higher than the freezing point of the liquid 101. The temperature of the liquid 101 stored in the liquid storage part 4a is, for example, room temperature (for example, 20°C).

[0078] The supply unit 4b is connected to the liquid storage unit 4a via a pipe. The supply unit 4b supplies the liquid 101 stored in the liquid storage unit 4a to the liquid nozzle 4d. The supply unit 4b may be, for example, a pump that is resistant to the liquid 101.

[0079] The flow control unit 4c is connected to the supply unit 4b through a pipe. 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. In addition, the flow control unit 4c can also start and stop the supply of the liquid 101.

[0080] The liquid nozzle 4d is provided inside the chamber 6. The liquid nozzle 4d has a cylindrical shape. One end of the liquid nozzle 4d is connected to the flow control unit 4c through a pipe.

[0081] The other end of the liquid nozzle 4d (the ejection side of the liquid 101) is arranged above the surface 100b of the substrate 100 placed on the mounting table 2a. The liquid 101 ejected from the liquid nozzle 4d is supplied to the surface 100b of the substrate 100. The other end of the liquid nozzle 4d can be arranged near the rotation center of the substrate 100. In this way, the liquid 101 can be supplied to the approximate center of the surface 100b of the substrate 100. The liquid 101 supplied to the approximate center of the surface 100b of the substrate 100 spreads toward the peripheral side of the surface 100b of the substrate 100, and a film of the liquid 101 having a substantially uniform thickness is formed on the surface 100b of the substrate 100.

[0082] Furthermore, if Figure 1 As shown, the opening (discharge port) at the other end of the liquid nozzle 4d may also be directed toward the side of the vibrating body 91 (main body 91a) on the rotation center side of the substrate 100 described later. In this way, the liquid 101 ejected from the liquid nozzle 4d is supplied to the surface 100b of the substrate 100 after hitting the side of the vibrating body 91 (main body 91a) on the rotation center side of the substrate 100. Therefore, the liquid 101 can be supplied to a wider area of ​​the surface 100b of the substrate 100, or the collision speed of the liquid 101 with the substrate 100 can be reduced. As a result, a film of the liquid 101 is more easily formed on the entire surface 100b of the substrate 100.

[0083] Alternatively, a hole may be provided in the vibrator 91 (main body 91a) to supply the liquid 101 to the surface 100b of the substrate 100 through the hole of the vibrator 91 (main body 91a). In other words, the vibrator 91 may function as the liquid nozzle 4d.

[0084] The second liquid supply unit 5 supplies the liquid 102 to the frozen film 101a containing the foreign matter 300 in the thawing process described later. The liquid 102 can be any liquid as long as it is difficult to react with the material of the substrate 100 and is difficult to remain on the surface 100b of the substrate 100 in the drying process described later. For example, the liquid 102 can be the same as the aforementioned liquid 101, and can be water (for example, pure water or ultrapure water), a liquid with water as the main component, a liquid in which a gas is dissolved, or the like.

[0085] In the present specification, a film formed by completely freezing the liquid 101 on the surface 100 b of the substrate 100 in a freezing step (solid-liquid phase) described later is referred to as a frozen film 101 a .

[0086] In this case, the liquid 102 may be the same as the liquid 101 or different from the liquid 101. When the liquid 102 is the same as the liquid 101, the second liquid supply unit 5 may be omitted. When the second liquid supply unit 5 is omitted, the first liquid supply unit 4 is also used in the thawing process described later. That is, the liquid 101 is also used in the thawing process.

[0087] Furthermore, the temperature of the liquid 102 can be set to a temperature higher than the freezing point of the liquid 102. For example, the temperature of the liquid 102 can be set to a temperature that can thaw the frozen liquid 101. The temperature of the liquid 102 is, for example, about room temperature (for example, 20° C.). In addition, if the temperature of the liquid 102 is set to a temperature higher than room temperature, the thawing time can be shortened. When the temperature of the liquid 102 is set to a temperature higher than room temperature, a heater and a temperature control device are provided in the liquid storage portion 5a described later, for example.

[0088] Furthermore, when the liquid 101 is also used in the thawing process, if the temperature of the liquid 101 is set to a temperature higher than normal temperature, the temperature of the film of the liquid 101 formed before the cooling process described later becomes high. If the temperature of the film of the liquid 101 becomes high, the time required for the cooling process becomes longer. Therefore, when the temperature of the liquid used in the thawing process is set to a temperature higher than normal temperature, even if the liquid 102 is the same as the liquid 101, it is preferable to provide the second liquid supply unit 5.

[0089] The second liquid supply unit 5 includes, for example, a liquid storage unit 5 a , a supply unit 5 b , a flow rate control unit 5 c , and a liquid nozzle 4 d .

[0090] The liquid storage part 5a may be the same as the aforementioned liquid storage part 4a. The supply part 5b may be the same as the aforementioned supply part 4b. The flow control part 5c may be the same as the aforementioned flow control part 4c.

[0091] also, Figure 1 2 illustrates a case where the first liquid supply unit 4 and the second liquid supply unit 5 share the liquid nozzle 4d. However, a liquid nozzle for supplying the liquid 101 and a liquid nozzle for supplying the liquid 102 may be provided separately.

[0092] The following will describe a case where the liquid nozzle 4d is used in common for supplying the liquid 101 and the liquid 102.

[0093] The chamber 6 is box-shaped. A cover plate 6a is provided inside the chamber 6. The cover plate 6a is used to receive the liquid 101 (liquid 102) supplied onto the substrate 100 and discharged to the outside of the substrate 100 by the rotation of the substrate 100. A partition plate 6b is provided inside the chamber 6. The partition plate 6b is provided between the outer surface of the cover plate 6a and the inner surface of the chamber 6.

[0094] A plurality of discharge ports 6c are provided on the side of the bottom surface of the chamber 6. The used cooling gas 3a1, the liquid 101 and the liquid 102, and the air 8a supplied by the air supply unit 8 are discharged from the discharge ports 6c to the outside of the chamber 6. The discharge port 6c is connected to an exhaust pipe 6c1. In addition, the discharge port 6c is also connected to a discharge pipe 6c2 for discharging the liquid 101 and the liquid 102.

[0095] The exhaust unit 7 is connected to the exhaust pipe 6c1. The exhaust unit 7 is used to exhaust the used cooling gas 3a1 and the air 8a. The exhaust unit 7 may be, for example, a pump or a blower.

[0096] The air supply unit 8 is provided on the ceiling surface of the chamber 6. In addition, the air supply unit 8 may be provided on the side surface of the chamber 6 as long as it is on the ceiling side. The air supply unit 8 is provided with, for example, an air blower such as a fan and a filter. The filter is, for example, a HEPA filter (high efficiency particulate air filter).

[0097] The vibrating portion 9 is used in the thawing process described later. In the thawing process, the vibrating portion 9 transmits vibration to the liquid film 103, which includes the liquid 102 (liquid 101) supplied to the frozen film 101a and the liquid (liquid 101) generated by thawing the frozen film 101a. For example, the vibrating portion 9 transmits vibration to the liquid film 103 from a direction intersecting the surface 100b of the substrate 100.

[0098] The vibration section 9 includes, for example, a vibration body 91 , a vibrator 92 , a circuit 93 , a holding section 94 , and a cover plate 95 .

[0099] Figure 2 It is a schematic perspective view of the vibrating body 91 .

[0100] also, Figure 2 The arrows X, Y, and Z in the figure represent three directions perpendicular to each other, wherein the X direction is a horizontal direction, and the Y direction is a horizontal direction perpendicular to the X direction.

[0101] like Figure 2 As shown, the vibrator 91 includes, for example, a body 91a and a flange 91b. The body 91a and the flange 91b are integrally formed. The vibrator 91 is made of a material that easily transmits vibration from the vibrator 92 and does not easily generate particles. The vibrator 91 is made of, for example, quartz.

[0102] The body 91a is, for example, in the shape of a cuboid. The dimension L of the body 91a in the X direction may be greater than the maximum dimension between the rotation center of the substrate 100 and the periphery of the substrate 100. For example, when the planar shape of the substrate 100 is a circle, the dimension L of the body 91a may be greater than the radius of the substrate 100. For example, when the planar shape of the substrate 100 is a quadrilateral, the dimension L of the body 91a may be greater than half of the diagonal dimension of the substrate 100.

[0103] In the thawing process described later, the substrate 100 is in a rotating state. Therefore, if the size L of the body 91a is larger than the maximum size between the rotation center of the substrate 100 and the periphery of the substrate 100, the vibration can be transmitted to the entire area of ​​the liquid film 103 even if the vibrator 91 is not moved during the thawing process.

[0104] The end 91aa of the main body 91a on the substrate 100 side may be a flat surface or may be Figure 2 As shown, a groove 91a1 is provided at the end 91aa. The groove 91a1 opens at the end 91aa of the body 91a. At least one groove 91a1 may be provided. The groove 91a1 extends along the X direction. In the X direction, the groove 91a1 opens at the side surfaces of both sides of the body 91a. In the case where a plurality of grooves 91a1 are provided, the plurality of grooves 91a1 may be provided side by side along the Y direction.

[0105] In addition, the function and effect of the groove 91a1 will be described in detail later.

[0106] The flange 91b is plate-shaped and is provided on the side opposite to the end 91aa side of the main body 91a. The flange 91b protrudes from the side of the main body 91a. The flange 91b may be in contact with the upper surface of the holding portion 94. The flange 91b may also be omitted. However, if the flange 91b is provided, it is easier to position the vibrating body 91 or stabilize the posture of the vibrating body 91 when the vibrating body 91 is mounted on the holding portion 94.

[0107] Next, the function and effect of the groove 91 a 1 of the vibrating body 91 will be described.

[0108] Figure 3 Schematic diagram showing the function and effect of the groove 91a1.

[0109] also, Figure 3 The arrows X, Y, Z and Figure 2 The same situation in .

[0110] like Figure 3 As shown, the side surface 91a1a of the groove 91a1 in the Y direction is inclined relative to the end 91aa. In addition, the side surface 91a1a on one side is inclined in the opposite direction to the side surface 91a1a opposite thereto.

[0111] like Figure 3 As shown, vibration 92a from vibrator 92 propagates inside vibrator 91 (main body 91a) and impinges on side surface 91a1a of groove 91a1. The direction in which vibration 92a impinging on side surface 91a1a propagates toward liquid film 103 changes according to the inclination angle of side surface 91a1a.

[0112] Here, assuming that the end 91aa of the vibrating body 91 is a flat surface, the propagation direction of the vibration 92a to the liquid film 103 will be approximately perpendicular to the surface 100b of the substrate 100. Therefore, the direction of the force acting on the foreign matter 300 will be approximately perpendicular to the upper surface of the frozen film 101a or the surface 100b of the substrate 100, so it is difficult for the foreign matter 300 to move in a direction parallel to the upper surface of the frozen film 101a or the surface 100b of the substrate 100. If it is difficult for the foreign matter 300 to move in a direction parallel to the upper surface of the frozen film 101a or the surface 100b of the substrate 100, it becomes difficult to separate and discharge the foreign matter 300.

[0113] In contrast, if a groove 91a1 is provided at the end 91aa of the vibrating body 91, Figure 3 As shown, the direction of the force acting on the foreign matter 300 is more likely to be a direction inclined relative to the upper surface of the freezing film 101a or the surface 100b of the substrate 100. When a force inclined relative to the upper surface of the freezing film 101a or the surface 100b of the substrate 100 acts on the foreign matter 300, a component force in a direction parallel to the upper surface of the freezing film 101a or the surface 100b of the substrate 100 will act on the foreign matter 300. Therefore, the foreign matter 300 is more likely to move in a direction parallel to the upper surface of the freezing film 101a or the surface 100b of the substrate 100. If the foreign matter 300 is more likely to move in a direction parallel to the upper surface of the freezing film 101a or the surface 100b of the substrate 100, the removal rate of the foreign matter 300 can be improved.

[0114] In this case, the angle θ between the side surface of the groove 91a1 and the extension line 91a1b of the end 91aa of the vibrator 91 is preferably set to 20°≦θ≦87°. This makes it easier to move the foreign matter 300, thereby further improving the removal rate of the foreign matter 300.

[0115] also, Figure 3 , the cross-sectional profile of the groove 91a1 is a trapezoid, but the cross-sectional profile of the groove 91a1 may also be a triangle, for example. In addition, the side surface of the groove 91a1 may be a plane or a curved surface. If the side surface of the groove 91a1 is a curved surface, the angle between the tangent line of the curved surface and the extension line of the end 91aa of the vibrating body 91 may be the aforementioned angle θ.

[0116] Next, return to Figure 1 , the vibrator 92 , the circuit 93 , the holding portion 94 , and the cover plate 95 provided on the vibration portion 9 are described.

[0117] The vibrator 92 is provided on the vibrating body 91 (flange 91b). The vibrator 92 may be, for example, joined to the vibrating body 91. The vibrator 92 converts an applied voltage into a force. The vibrator 92 is, for example, a piezoelectric element or the like.

[0118] The circuit 93 is electrically connected to the vibrator 92. The circuit 93 applies a voltage of a specific frequency to the vibrator 92. In this case, the frequency is, for example, about 1.6 MHz to 4 MHz. In addition, the circuit 93 can control the energy of the vibration and control the start and stop of the vibration. The circuit 93 controls the energy of the vibration by changing at least one of the amplitude and the angular frequency, for example.

[0119] The holding portion 94 holds the vibrator 91 at a predetermined position above the substrate 100. In this case, the distance between the end 91aa of the vibrator 91 (main body 91a) and the surface 100b of the substrate 100 is preferably set to 1.8 mm or less. In this way, the liquid film 103 can be more easily held between the end 91aa of the vibrator 91 (main body 91a) and the surface 100b of the substrate 100. Therefore, the vibration can be efficiently transmitted from the vibrator 91 (main body 91a) to the liquid film 103.

[0120] The holding portion 94 is, for example, in a plate shape and has a hole extending through the thickness thereof. The main body 91a of the vibrating body 91 can be inserted into the hole. When the main body 91a is inserted into the hole, the flange 91b of the vibrating body 91 can be brought into contact with the upper surface of the holding portion 94. The flange 91b can be mounted on the holding portion 94 using fasteners such as screws.

[0121] Furthermore, the holding portion 94 can also move in a direction parallel to the surface 100b of the substrate 100. For example, a rotation axis can be provided near the end of the holding portion 94 on the opposite side to the side where the vibrating body 91 is provided, so that the holding portion 94 holding the vibrating body 91 can rotate. For example, in the thawing process described later, the holding portion 94 can be rotated so that the vibrating body 91 is located above the surface 100b of the substrate 100, and in other processes, the holding portion 94 can be rotated so that the vibrating body 91 moves to a retreat position outside the substrate 100.

[0122] Therefore, in the thawing step described later, the vibration section 9 (vibration body 91 ) faces the frozen film 101 a .

[0123] The cover plate 95 is provided on the upper surface of the holding portion 94. The cover plate 95 covers the vibrator 92. The cover plate 95 can be attached to the holding portion 94 using fasteners such as screws.

[0124] The detection unit 10 detects the thawing state (dissolution state) of the frozen film 101a in the thawing process described later. In the thawing process, when the frozen film 101a begins to thaw, the aforementioned liquid film 103 is formed on the remaining frozen film 101a that has not yet thawed. Therefore, by detecting the position of the upper surface of the remaining frozen film 101a (the interface position of the liquid film 103 and the frozen film 101a), the thawing state can be detected.

[0125] For example, the detection unit 10 may be a reflective optical sensor. In this case, the detection unit 10 irradiates light to the liquid film 103 and receives light reflected at the interface between the liquid film 103 and the frozen film 101a. Then, the detection unit 10 detects the position of the interface based on the received reflected light. If the detection unit 10 is a reflective optical sensor, it is possible to directly detect the position of the upper surface of the frozen film 101a.

[0126] Alternatively, the detection unit 10 may indirectly detect the position of the upper surface of the frozen film 101 a .

[0127] For example, in the freezing process described later, when the film of the liquid 101 is completely frozen to form a frozen film 101a, due to volume expansion, the thickness of the frozen film 101a will be thicker than the thickness of the film of the liquid 101 before freezing. Then, in the thawing process, as the frozen film 101a thaws, the thickness of the frozen film 101a will gradually become thinner. The thickness of the film of the liquid 101 generated by the thawing of the frozen film 101a will be thinner than the thickness of the thawed frozen film 101a. Therefore, as the thawing of the frozen film 101a proceeds, the total thickness of the remaining frozen film 101a and the liquid film 103 above the frozen film 101a will gradually decrease.

[0128] Therefore, by detecting the position of the upper surface of the liquid film 103, the position of the upper surface of the frozen film 101a below the liquid film 103 can be obtained. In addition, the relationship between the position of the upper surface of the liquid film 103 and the position of the upper surface of the frozen film 101a below the liquid film 103 can be obtained by performing experiments or simulations in advance.

[0129] When detecting the position of the upper surface of the liquid film 103 , the detection unit 10 may be a non-contact displacement meter such as a laser displacement meter or an ultrasonic displacement meter.

[0130] Furthermore, by detecting the temperature of the upper surface of the liquid film 103 , the position of the upper surface of the frozen film 101 a below the liquid film 103 can also be indirectly detected.

[0131] For example, in the thawing process, as the frozen film 101a thaws, the volume of the liquid film 103 above the frozen film 101a gradually increases. Since the temperature of the liquid film 103 is higher than the temperature of the frozen film 101a, as the volume of the liquid film 103 increases (i.e., as the thawing proceeds), the temperature of the upper surface of the liquid film 103 increases. Therefore, by detecting the temperature of the upper surface of the liquid film 103, the position of the upper surface of the frozen film 101a below the liquid film 103 can be indirectly detected. In addition, the relationship between the temperature of the upper surface of the liquid film 103 and the position of the upper surface of the frozen film 101a below the liquid film 103 can be obtained by conducting experiments or simulations in advance.

[0132] When detecting the temperature of the upper surface of the liquid film 103 , the detection unit 10 may be, for example, a non-contact thermometer such as a radiation thermometer or a thermal imager.

[0133] Furthermore, the position of the upper surface of the frozen film 101 a below the liquid film 103 can also be obtained based on the time from the start of thawing.

[0134] For example, the temperature of the liquid 101 (liquid 102) used in the thawing process is controlled within a specific range, and the relationship between the time from the start of thawing (for example, the start of supply of the liquid 101 (liquid 102)) and the position of the upper surface of the frozen film 101a below the liquid film 103 is obtained by performing experiments or simulations in advance. In this way, the position of the upper surface of the frozen film 101a below the liquid film 103 can be indirectly detected by the time from the start of thawing (for example, the time from the start of supply of the liquid 102 from the second liquid supply unit 5).

[0135] If the position of the upper surface of the frozen film 101a is obtained by time management, it is possible to omit the detection unit 10. If the detection unit 10 can be omitted, the structure of the substrate processing apparatus 1 can be simplified and the manufacturing cost can be reduced.

[0136] However, if the position of the upper surface of the freezing film 101 a is detected by the detection unit 10 , the position of the upper surface of the freezing film 101 a can be obtained more accurately.

[0137] In addition, the purpose and effect of detecting the position of the upper surface of the frozen film 101 a in the thawing process will be described in detail later.

[0138] The controller 11 controls the operation of each element provided in the substrate processing apparatus 1. The controller 11 includes, for example, a computing unit such as a CPU (central processing unit) and a storage unit such as a semiconductor memory. The controller 11 is, for example, a computer. The storage unit stores a control program for controlling the operation of each element provided in the substrate processing apparatus 1. The computing unit sequentially executes the preparatory process, the film forming process of the liquid 101, the cooling process, the thawing process, and the drying process described later based on the control program stored in the storage unit.

[0139] Figure 4 It is a schematic perspective view of a vibrating body 96 according to another embodiment.

[0140] also, Figure 4 The arrows X, Y, Z and Figure 2 The same situation in .

[0141] like Figure 4 As shown, the vibrating body 96 includes, for example, a body 96a and a flange 96b. The body 96a and the flange 96b are integrally formed. The material of the vibrating body 96 can be, for example, the same as the material of the vibrating body 91 described above.

[0142] The flange 96b can be the same as the flange 91b described above.

[0143] The dimension L1 of the body 96a in the X direction may be the same as the dimension L of the body 91a described above. The side surface 96a1 of the body 96a in the Y direction is connected to the end 96aa of the vibrating body 96 (body 96a). The side surface 96a1 is inclined relative to the end 96aa of the vibrating body 96 (body 96a). The angle θ1 between the side surface 96a1 of the body 96a and the extension line 96ab of the end 96aa of the vibrating body 96 (body 96a) may be the same as the angle θ described above.

[0144] Figure 5 Schematic diagram showing the function and effect of the vibrating body 96 .

[0145] like Figure 5 As shown in FIG. 1 , in the vibrating body 96, the vibration 92a from the vibrator 92 propagates inside the vibrating body 96 (body 96a) and is incident on the side 96a1 of the body 96a. The area of ​​the side 96a1 that is not in contact with the liquid film 103 (the area in contact with the outside air) is prone to total reflection according to Snell's law. Therefore, in the area of ​​the side 96a1 that is not in contact with the liquid film 103, the vibration 92a is repeatedly reflected and propagated. For example, in Figure 5, the vibration 92a incident on the side surface 96a1 from above in a direction inclined relative to the Z direction is a vibration reflected once on the side surface 96a1. The vicinity of the end 96aa of the vibrating body 96 (main body 96a) is in contact with the liquid film 103. For example, the vicinity of the end 96aa of the vibrating body 96 (main body 96a) is inserted into the liquid film 103. Due to the surface tension of the liquid film 103 and the flow of the liquid film 103 caused by the rotation of the substrate 100, the liquid film 103 is in contact with the vicinity of the end 96aa of the vibrating body 96 (main body 96a). The vibration 92a incident on the portion of the side surface 96a1 that is in contact with the liquid film 103 is more likely to be emitted from the vibrating body 96 (main body 96a) according to Snell's law. In this case, the propagation direction of the vibration 92a changes in accordance with the angle θ1.

[0146] In addition, if Figure 5 As shown, there is also vibration 92a which is incident on the side surface 96a1 from above in a direction substantially parallel to the Z direction and is emitted from the vibrating body 96 (main body 96a) without any reflection on the side surface 96a1.

[0147] In the vibrating body 96, as Figure 5 As shown in FIG. 1 , the direction of the force acting on the foreign matter 300 tends to be inclined relative to the upper surface of the freezing film 101a or the surface 100b of the substrate 100. Figure 3 As described in the above, the component force in the direction parallel to the upper surface of the freezing film 101a or the surface 100b of the substrate 100 acts on the foreign matter 300, making it easier for the foreign matter 300 to move in the direction parallel to the upper surface of the freezing film 101a or the surface 100b of the substrate 100. If the foreign matter 300 moves in the direction parallel to the upper surface of the freezing film 101a or the surface 100b of the substrate 100 more easily, the removal rate of the foreign matter 300 can be improved.

[0148] also, Figure 5 The end 96aa of the vibrating body 96 (main body 96a) in the example is a flat surface, but the groove 91a1 having the above-mentioned inclined surface can also be provided in the end 96aa. In addition, the side surface of the vibrating body 91 (main body 91a) can also be provided as an inclined surface.

[0149] Figure 6 It is a schematic perspective view showing a vibrating body 97 according to another embodiment.

[0150] like Figure 6As shown, the vibrating body 97 has a side surface 97a that is inclined relative to the end of the vibrating body 97. For example, the vibrating body 97 may be the result of reducing the size L1 of the vibrating body 96 described above. In addition, the vibrating body 97 may also be the result of reducing the size L of the vibrating body 91 described above. The size L3 of the vibrating body 97 may be set to be smaller than the minimum size between the rotation center of the substrate 100 and the periphery of the substrate 100. In this way, the miniaturization and cost reduction of the vibrating body 97 can be achieved. However, if the size L3 is reduced, the vibration can only be transmitted to a partial area of ​​the liquid film 103. Therefore, it is necessary to move the position of the vibrating body 97 between the rotation center of the substrate 100 and the periphery of the substrate 100. For example, a holding portion that enables the vibrating body 97 to move in a direction parallel to the surface 100b of the substrate 100 may be provided.

[0151] As described above, the substrate processing apparatus 1 of this embodiment forms the frozen film 101a on the surface 100b of the substrate 100. Then, the foreign matter 300 attached to the surface 100b of the substrate 100 is taken into the frozen film 101a, and the frozen film 101a containing the foreign matter 300 is thawed to remove the foreign matter 300 from the surface 100b of the substrate 100.

[0152] Next, the operation of the substrate processing apparatus 1 will be further described.

[0153] Figure 7 1 is a timing chart showing the operation of the substrate processing apparatus 1 .

[0154] Figure 8 : is a graph showing the temperature change of the liquid 101 supplied onto the surface 100 b of the substrate 100 .

[0155] also, Figure 7 and Figure 8 The illustrated case is a case where the substrate 100 is a 6025 quartz (Qz) substrate (152 mm×152 mm×6.35 mm), and the liquid 101 and the liquid 102 are pure water.

[0156] In addition, the liquid 102 used for thawing is the same as the liquid 101. Figure 7 and Figure 8 In the thawing process, liquid 101 is used.

[0157] First, the substrate 100 is carried into the chamber 6 through a not-shown carrying-in / out port of the chamber 6. The carried-in substrate 100 is placed and supported on the plurality of supporting portions 2a1 of the mounting table 2a.

[0158] After the substrate 100 is supported on the mounting table 2a, Figure 7 and Figure 8As shown, a freeze cleaning process including a preliminary process, a film forming process of the liquid 101, a cooling process, a thawing process, and a drying process is performed.

[0159] First, if Figure 7 and Figure 8 As shown, a preparatory process is performed.

[0160] In the preparatory process, the controller 11 controls the supply unit 4b and the flow control unit 4c to supply a predetermined flow rate of the liquid 101 to the surface 100b of the substrate 100. Furthermore, the controller 11 controls the flow control unit 3c to supply a predetermined flow rate of the cooling gas 3a1 to the back side 100a of the substrate 100. Furthermore, the controller 11 controls the drive unit 2c to rotate the substrate 100 at the second rotation speed.

[0161] Here, when the cooling gas 3a1 is supplied to cool the atmosphere inside the chamber 6, frost containing dust in the atmosphere may adhere to the substrate 100, causing contamination. Therefore, in the preparatory process, the liquid 101 is continuously supplied to the surface 100b of the substrate 100. That is, in the preparatory process, while cooling the substrate 100, frost is prevented from adhering to the surface 100b of the substrate 100.

[0162] The second rotation speed is, for example, about 50 rpm to 500 rpm. The flow rate of the liquid 101 is, for example, about 0.1 L / min to 1.0 L / min. The flow rate of the cooling gas 3a1 is, for example, about 40 NL / min to 200 NL / min. The process time of the preparatory process is about 1800 seconds.

[0163] Since the liquid 101 is continuously supplied, the temperature of the liquid 101 film in the preliminary step is almost the same as the temperature of the supplied liquid 101. For example, when the temperature of the supplied liquid 101 is about room temperature (20°C), the temperature of the liquid 101 film is also about room temperature (20°C).

[0164] Next, if Figure 7 and Figure 8 As shown, a step of forming a film of liquid 101 is performed.

[0165] In the process of forming the film of the liquid 101, the supply of the liquid 101 supplied in the preliminary process is stopped. Since the rotation of the substrate 100 is still maintained, the liquid 101 on the surface 100b of the substrate 100 is discharged. In this case, the rotation speed of the substrate 100 is decelerated to a first rotation speed, and the first rotation speed can suppress the uneven thickness of the film of the liquid 101 caused by the centrifugal force. The first rotation speed is, for example, 0 rpm to 50 rpm.

[0166] After the rotation speed of the substrate 100 is set to the first rotation speed, a predetermined amount of liquid 101 is supplied to the substrate 100 to form a film of the liquid 101. The thickness of the film of the liquid 101 (the thickness of the film of the liquid 101 during the cooling process) is, for example, about 300 μm to 1300 μm.

[0167] In addition, during the process of forming the film of the liquid 101, the flow rate of the cooling gas 3a1 is maintained at the same flow rate as that in the preliminary process. In the aforementioned preliminary process, the in-plane temperature of the substrate 100 becomes substantially uniform. In the process of forming the film of the liquid 101, if the flow rate of the cooling gas 3a1 is maintained at the same flow rate as that in the preliminary process, the in-plane temperature of the substrate 100 can be maintained in a substantially uniform state.

[0168] Next, if Figure 7 and Figure 8 As shown, a cooling process is performed.

[0169] In addition, in this specification, the cooling process includes a "supercooling process", a "freezing process (solid-liquid phase)", and a "freezing process (solid phase)". The "supercooling process" refers to the process from when the liquid 101 is in a supercooled state until the liquid 101 in the supercooled state begins to freeze. In the supercooling process, only the liquid 101 exists on the entire surface 100b of the substrate 100. The "freezing process (solid-liquid phase)" refers to the process from when the liquid 101 in the supercooled state begins to freeze until the freezing is completely completed. In the freezing process (solid-liquid phase), the liquid 101 and the product obtained by freezing the liquid 101 exist on the entire surface 100b of the substrate 100. The "freezing process (solid phase)" refers to the process after the liquid 101 is completely frozen. In the freezing process (solid phase), only the frozen film 101a formed by the freezing of the liquid 101 exists on the entire surface 100b of the substrate 100.

[0170] Furthermore, after the formation process of the film of the liquid 101, the freezing process (solid-liquid phase) is sometimes performed without the supercooling process, and the thawing process is performed before the frozen film 101a is formed. And, after the formation process of the film of the liquid 101, the freezing process (solid-liquid phase), the freezing process (solid phase), and the thawing process are sometimes performed in sequence without the supercooling process. In other words, the supercooling process and the freezing process (solid phase) are sometimes omitted. Even if the supercooling process and the freezing process (solid phase) are omitted, the foreign matter 300 can be separated from the surface 100b of the substrate 100. If the supercooling process and the freezing process (solid phase) are omitted, the cooling process can be simplified, thereby shortening the time required for the cooling process.

[0171] In the supercooling process, by continuously supplying the cooling gas 3a1 to the back side 100a of the substrate 100, the temperature of the film of the liquid 101 on the surface 100b of the substrate 100 is further reduced to a temperature lower than the temperature of the film of the liquid 101 in the film formation process of the liquid 101, and the supercooling state is achieved. In this case, if the cooling speed of the liquid 101 is too fast, the liquid 101 cannot reach the supercooling state and freezes immediately. Therefore, the controller 11 controls at least any one of the rotation speed of the substrate 100, the flow rate of the cooling gas 3a1, and the flow rate of the liquid 101, so that the liquid 101 on the surface 100b of the substrate 100 reaches the supercooling state.

[0172] The control conditions for the liquid 101 to reach the supercooled state are affected by factors such as the size of the substrate 100, the viscosity of the liquid 101, the specific heat of the cooling gas 3a1, etc. Therefore, the control conditions for the liquid 101 to reach the supercooled state are preferably appropriately determined by conducting experiments or simulations in advance.

[0173] In addition, as described above, the overcooling process may not be performed. In this case, the controller 11 controls at least one of the rotation speed of the substrate 100, the flow rate of the cooling gas 3a1, and the flow rate of the liquid 101 to accelerate the cooling rate of the liquid 101. By accelerating the cooling rate of the liquid 101, the freezing process (solid-liquid phase) can be performed without the overcooling process.

[0174] When the supercooled liquid 101 begins to freeze, the supercooling process is changed to the freezing process (solid-liquid phase). In the supercooled state, the liquid 101 begins to freeze due to, for example, the temperature of the film of the liquid 101, the presence of foreign matter 300 such as particles or bubbles, vibration, etc. For example, in the presence of foreign matter 300 such as particles, when the temperature T of the liquid 101 reaches above -35°C and below -20°C, the liquid 101 begins to freeze. In addition, it is also possible to apply vibration to the liquid 101 by changing the rotation of the substrate 100, etc., so as to start the freezing of the liquid 101.

[0175] As described above, in the supercooled liquid 101, a certain proportion of the starting point of freezing becomes foreign matter 300. The foreign matter 300 that becomes the starting point of freezing is more likely to be taken into the frozen film 101a. Therefore, by performing the supercooling process, the removal rate of the foreign matter 300 can be improved. In addition, the foreign matter 300 attached to the surface 100b of the substrate 100 may be separated by the pressure wave caused by the volume change when the liquid 101 changes to a solid or the physical force caused by the volume increase.

[0176] Next, if Figure 7 and Figure 8 As shown, a thawing process is performed.

[0177] The start of the thawing process can be determined, for example, based on the time elapsed from the start of the preparatory process or the start of the freezing process (solid-liquid phase). Based on the length of this elapsed time, it is determined whether the thawing starts during the freezing process (solid-liquid phase) or during the freezing process (solid phase). In addition, the surface state of the liquid 101 (frozen film 101a) on the surface 100b side of the substrate 100 can be detected and the start time of the thawing can be determined based on the change in the surface state.

[0178] Furthermore, in the thawing step, the vibration 92a is transmitted by the vibrating unit 9 to the liquid film 103 including the liquid 101 (liquid 102) supplied for thawing and the liquid 101 generated by thawing the frozen film 101a.

[0179] In addition, the details of the thawing process will be described later.

[0180] Next, if Figure 7 Figure 8 As shown, a drying process is performed.

[0181] During the drying process, the controller 11 controls the supply unit 4b and the flow control unit 4c to stop the supply of the liquid 101. If the liquid 101 and the liquid 102 are different liquids, the controller 11 controls the supply unit 5b and the flow control unit 5c to stop the supply of the liquid 102.

[0182] Furthermore, the controller 11 controls the flow rate control unit 3c to stop the supply of the cooling gas 3a1.

[0183] The controller 11 controls the circuit 93 to stop the vibration 92 a . The controller 11 can also control the holding unit 94 to move the vibrator 91 (vibrator 96 , vibrator 97 ) to a retreat position outside the substrate 100 .

[0184] In addition, the controller 11 controls the driving unit 2c to set the rotation speed of the substrate 100 to a fourth rotation speed that is faster than the rotation speed of the substrate 100 in the thawing process (the third rotation speed described later). By increasing the rotation speed of the substrate 100, the drying time of the substrate 100 can be shortened. In addition, the fourth rotation speed is not particularly limited as long as drying is possible.

[0185] Through the above operation, the freezing cleaning process ends. In addition, the freezing cleaning process can also be performed multiple times.

[0186] The substrate 100 that has completed the freeze cleaning process is carried out of the chamber 6 through a not-shown loading / unloading port of the chamber 6 .

[0187] Next, the thawing process will be further described.

[0188] In the thawing process, the controller 11 controls the supply unit 4b and the flow control unit 4c to supply the liquid 101 to the frozen film 101a. In addition, when the liquid 101 and the liquid 102 are different, the controller 11 controls the supply unit 5b and the flow control unit 5c to supply the liquid 102 to the frozen film 101a.

[0189] The flow rate of the liquid 101 or the liquid 102 is not particularly limited as long as it can thaw. The temperature of the liquid 101 or the liquid 102 can be set to room temperature (for example, 20° C.). In addition, as described above, the temperature of the liquid 101 can be set to room temperature (for example, 20° C.), and the temperature of the liquid 102 for thawing can be set to a temperature higher than room temperature.

[0190] Furthermore, the controller 11 controls the driving unit 2c to increase the rotation speed of the substrate 100 from the first rotation speed to the third rotation speed. The third rotation speed is, for example, about 200rpm to 700rpm. By increasing the rotation speed of the substrate 100, the liquid 101 and the objects obtained by freezing the liquid 101 can be thrown off by centrifugal force. Therefore, it is easier to discharge the liquid 101 and the objects obtained by freezing the liquid 101 from the surface 100b of the substrate 100. In this process, the foreign matter 300 separated from the surface 100b of the substrate 100 will also be discharged together with the liquid 101 and the objects obtained by freezing the liquid 101.

[0191] Furthermore, the controller 11 controls the circuit 93 to cause the vibrator 92 to generate vibration 92a. The generated vibration 92a is transmitted to the liquid film 103 via the vibrator 91 (vibrator 96, vibrator 97).

[0192] like Figure 7 As shown, the timing of generating vibration 92a may be simultaneous with the start of supply of liquid 101 (liquid 102) for thawing, or may be as follows: Figure 7 As shown by the dotted line in FIG. 1 , the supply of liquid 101 (liquid 102) is started after the supply of liquid 101 (liquid 102) is started. The timing of stopping vibration 92a may be performed simultaneously with the supply of liquid 101 (liquid 102) for thawing, or may be performed as follows: Figure 7 As indicated by the dot-dash line in FIG. 1 , this is performed before the supply of the liquid 101 (liquid 102) is stopped.

[0193] When the vibration 92a is transmitted to the liquid film 103, the foreign matter 300 separated from the surface 100b of the substrate 100 is suppressed from being reattached to the surface 100b of the substrate 100. Therefore, the removal rate of the foreign matter 300 can be improved.

[0194] Next, the purpose and effect of detecting the position of the upper surface of the frozen film 101 a in the thawing process will be further described.

[0195] As described above, when the vibration 92a is transmitted to the liquid film 103, the re-adhesion of the separated foreign matter 300 can be suppressed. In this case, if the energy of the vibration 92a is increased, the re-adhesion of the separated foreign matter 300 can be suppressed more effectively.

[0196] Fig. 9 (a) to Fig. 9 (c) is a schematic process cross-sectional view showing the thawing process.

[0197] like Fig. 9 As shown in (a), the foreign matter 300 separated from the surface 100b of the substrate 100 is taken into the frozen film 101a.

[0198] like Fig. 9 As shown in (b), when the frozen film 101a starts to thaw, a liquid film 103 is formed on the remaining frozen film 101a that has not yet thawed. And the vibration 92a is transmitted to the liquid film 103. When the vibration 92a is transmitted to the liquid film 103, the re-attachment of the separated foreign matter 300 can be suppressed.

[0199] However, a pattern 100c is formed on the surface 100b of the substrate 100. The pattern 100c is, for example, a fine concave-convex portion. Fig. 9 As shown in (c), when the frozen film 101a is completely thawed and the vibration 92a is transmitted to the liquid film 103, the vibration 92a is transmitted to the pattern 100c.

[0200] Since the pattern 100c is composed of fine concave and convex parts, the rigidity is low. Therefore, when the vibration 92a is transmitted to the pattern 100c, Fig. 9 As shown in (c), the pattern 100c may be damaged.

[0201] In this case, if the energy of the vibration 92 a is simply reduced to suppress damage to the pattern 100 c , the separated foreign matter 300 is likely to be attached to the surface 100 b of the substrate 100 again.

[0202] Here, from Fig. 9 As can be seen from (b), pattern 100c located on surface 100b of substrate 100 is held by frozen film 101a below liquid film 103. If pattern 100c is held by frozen film 101a, even if vibration 92a is transmitted to pattern 100c, damage to pattern 100c can be suppressed.

[0203] Therefore, in the substrate processing apparatus 1 of the present embodiment, the position of the upper surface of the remaining frozen film 101a below the liquid film 103 is directly or indirectly detected by the detection unit 10. In addition, as described above, when the detection unit 10 is not provided, the position of the upper surface of the remaining frozen film 101a below the liquid film 103 is indirectly detected by the time from the start of thawing.

[0204] Then, when the distance between the upper surface of the freezing film 101a and the surface 100b of the substrate 100 is greater than a predetermined value, as shown in FIG. Figure 7 As shown, the energy of vibration 92a is increased. If the energy of vibration 92a is large, it is possible to effectively prevent the separated foreign matter 300 from attaching to the surface 100b of the substrate 100 again. In this case, the pattern 100c is held by the frozen film 101a, so it is possible to prevent the pattern 100c from being damaged.

[0205] Then, when the distance between the upper surface of the freezing film 101a and the surface 100b of the substrate 100 becomes smaller than a predetermined value, as shown in FIG. Figure 7 As shown, the energy of vibration 92a is reduced, or as Figure 7 As indicated by the dot-dash line in the figure, vibration 92a is stopped.

[0206] That is, the controller 11 controls the vibration unit 9 to reduce the energy of the vibration 92a transmitted to the liquid film 103 or stop the vibration 92a according to the position of the upper surface of the freezing film 101a below the liquid film 103. By reducing the energy of the vibration 92a or stopping the vibration 92a, even if the pattern 100c is exposed from the freezing film 101a, it is possible to suppress the damage to the pattern 100c.

[0207] In this case, the controller 11 switches the energy of the vibration 92a in the vibrator 92 or stops the vibration 92a in the vibrator 92 through the control circuit 93. The energy of the vibration 92a can be controlled by changing at least one of the amplitude and the angular frequency, for example.

[0208] When reducing the energy of vibration 92a, it can be set to 10% to 50% of the energy of vibration 92a when frozen film 101a begins to thaw. In addition, the energy of vibration 92a can be gradually or stepwise reduced according to the change in the position of the upper surface of frozen film 101a.

[0209] Fig.10 (a) to Fig.10 (c) is a schematic cross-sectional view showing the position of the upper surface of the frozen film 101a when the energy of the vibration 92a is switched or the vibration 92a is stopped.

[0210] In the case where the substrate 100 is, for example, an EUV (extreme ultraviolet) mask or a semiconductor wafer, the pattern 100c sometimes has a multilayer structure in which a plurality of film layers are stacked. In this case, when the top of the pattern 100c is exposed from the upper surface of the freezing film 101a, the top layer of the pattern 100c may be peeled off. Therefore, when the pattern 100c has a multilayer structure, such as Fig.10 As shown in (a), the energy of the vibration 92a can be reduced or the vibration 92a can be stopped when the distance between the upper surface of the freezing film 101a and the surface 100b of the substrate 100 is only greater than the distance between the top of the pattern 100c and the surface 100b of the substrate 100. Fig.10 As shown in (b), the energy of vibration 92a can be reduced or vibration 92a can be stopped when the distance between the upper surface of freezing film 101a and surface 100b of substrate 100 is equal to the distance between the top of pattern 100c and surface 100b of substrate 100. Through these methods, even if pattern 100c has a multi-layer structure, it is possible to suppress damage to pattern 100c.

[0211] Furthermore, when the substrate 100 is, for example, a phase shift mask, an imprint template, or a plate-like body for MEMS, the pattern 100c may have a single-layer structure. Fig.10 As shown in (c), when the distance between the upper surface of the freezing film 101a and the surface 100b of the substrate 100 becomes smaller than the distance between the top of the pattern 100c and the surface 100b of the substrate 100, the energy of the vibration 92a can be reduced or the vibration 92a can be stopped. If the pattern 100c has a single-layer structure, since there is no peeling problem like a multi-layer structure, even if the top of the pattern 100c is slightly exposed from the upper surface of the freezing film 101a, it is possible to suppress damage to the pattern 100c. In addition, even if the pattern 100c has a single-layer structure, when it becomes Fig.10 (a) Fig.10 At the time when the upper surface of the frozen film 101a shown in (b) is located, the energy of the vibration 92a can be reduced or the vibration 92a can be stopped.

[0212] In other words, when the upper surface of the frozen film 101a is close to the top of the pattern 100c, the controller 11 can control the vibrator 9 to reduce the energy of the vibration 92a transmitted to the liquid film 103 or stop the vibration 92a.

[0213] As described above, the position of the upper surface of the freezing film 101a when switching the energy of the vibration 92a or stopping the vibration 92a can be adjusted according to the structure of the pattern 100c. Fig.10By switching the energy of the vibration 92a or stopping the vibration 92a at the position of the upper surface of the freezing film 101a shown in (b), it is possible to adapt to the structure of various patterns 100c.

[0214] As described above, the processing method of the substrate 100 of the present embodiment is to form a frozen film 101a on the surface 100b of the substrate 100, absorb the foreign matter 300 attached to the surface 100b of the substrate 100 into the frozen film 101a, thaw the frozen film 101a containing the foreign matter 300, and remove the foreign matter 300 from the surface 100b of the substrate 100.

[0215] The method for processing the substrate 100 may include the following steps.

[0216] A step of supplying liquid to the frozen film 101 a including the foreign matter 300 .

[0217] The process of transmitting vibration from the vibration unit 9 facing the frozen film 101a to the liquid film 103 including the liquid 102 (liquid 101) supplied to the frozen film 101a and the liquid (liquid 101) generated by thawing the frozen film 101a.

[0218] Then, in the step of transmitting the vibration to the liquid film 103 , the energy of the vibration transmitted to the liquid film 103 is reduced or the vibration is stopped according to the position of the upper surface of the frozen film 101 a below the liquid film 103 .

[0219] In addition, the content of each step can be the same as the above content, so the detailed description is omitted.

[0220] The above embodiments are exemplified. However, the present invention is not limited to these descriptions. For the above embodiments, as long as they have the characteristics of the present invention, those skilled in the art can appropriately add, delete or change the design of the constituent elements, or add, omit or change the conditions of the processes, which are also included in the scope of the present invention.

[0221] For example, the shape, size, number, arrangement, etc. of each element included in the substrate processing apparatus 1 are not limited to those illustrated, and can be changed as appropriate.

Claims

1. A substrate processing device, which forms a frozen film on the surface of a substrate, takes foreign matter attached to the surface of the substrate into the frozen film, thaws the frozen film containing the foreign matter, and removes the foreign matter from the surface of the substrate, and is characterized in that include: a liquid supply unit for supplying liquid to the frozen film containing the foreign matter; a vibration portion, opposite to the freezing film; as well as A controller controls the vibration unit, wherein: The controller controls the vibration unit. transmitting vibration to a liquid film including the liquid supplied to the frozen film and liquid generated by thawing the frozen film, The energy of the vibration transmitted to the liquid film is reduced or the vibration is stopped according to the position of the upper surface of the frozen film below the liquid film.

2. The substrate processing device according to claim 1, characterized in that: The method further includes a detection unit for directly or indirectly detecting a position of an upper surface of the frozen film.

3. The substrate processing device according to claim 2, characterized in that: The detection unit is an optical sensor that detects a position of an upper surface of the frozen film.

4. The substrate processing device according to claim 2, characterized in that: The detection unit is a displacement meter that detects the position of the upper surface of the liquid film.

5. The substrate processing device according to claim 2, characterized in that: The detection unit is a thermometer that detects the temperature of the liquid film.

6. The substrate processing apparatus according to claim 1, wherein: The position of the upper surface of the frozen film is detected based on the time from when the liquid supply unit starts supplying the liquid.

7. The substrate processing apparatus according to any one of claims 1 to 6, characterized in that: The controller controls the vibration unit to reduce the energy of the vibration gradually or in stages.

8. The substrate processing apparatus according to any one of claims 1 to 6, characterized in that: The surface of the substrate is provided with a pattern, When the position of the upper surface of the frozen film is near the position of the top of the pattern, the controller controls the vibration unit to reduce the energy of the vibration transmitted to the liquid film or to stop the vibration.

9. A substrate processing method, which is a method of forming a frozen film on the surface of a substrate, taking foreign matter attached to the surface of the substrate into the frozen film, thawing the frozen film containing the foreign matter, and removing the foreign matter from the surface of the substrate, and characterized in that include: The process of supplying liquid to the frozen film containing the foreign matter; as well as a step of transmitting vibration from a vibration portion opposed to the frozen film to a liquid film including the liquid supplied to the frozen film and liquid generated by thawing the frozen film, wherein: In the step of transmitting the vibration to the liquid film, the energy of the vibration transmitted to the liquid film is reduced or the vibration is stopped according to the position of the upper surface of the frozen film below the liquid film.

Images