Substrate processing apparatus and method of processing substrate

Abstract

To provide a substrate processing apparatus capable of performing proper processing using a processing liquid including an OH radical, and a method of processing the substrate.SOLUTION: A substrate processing device comprises a mount part which rotates a mounted substrate, a nozzle which extends along a surface of the substrate, and a light source which irradiates a raw material liquid flowing inside the nozzle with ultraviolet light.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a substrate processing apparatus and a method for processing a substrate. [Background technology]

[0002] 2. Description of the Related Art In the manufacture of semiconductor devices, photomasks, flat panel displays, and the like, treatments are carried out to remove particles, organic matter, and the like adhering to the surface of a substrate.

[0003] For example, a technique has been proposed in which ozone water is supplied to the surface of a substrate to which particles, organic matter, etc. are attached, thereby decomposing and removing the particles, organic matter, etc. However, removal using ozone water alone does not provide a sufficient removal effect.

[0004] For this reason, a technique has been proposed in which ozone water supplied to the surface of the substrate is irradiated with ultraviolet light (see, for example, Patent Document 1). By irradiating ozone water with ultraviolet light, a processing solution containing OH radicals can be produced. By using a processing solution containing OH radicals, particles and organic matter adhering to the surface of a substrate can be decomposed and removed using the OH radicals.

[0005] However, supplying ozone water to the surface of a substrate and irradiating it with ultraviolet light can oxidize the surface of the substrate, potentially changing its surface properties. Furthermore, the ozone water supplied to the surface of the substrate is discharged within a relatively short period of time. This reduces the cumulative amount of ultraviolet light irradiated onto the ozone water, thereby reducing the efficiency of OH radical generation. Furthermore, it is difficult to uniformly irradiate the ozone water on the surface of the substrate with ultraviolet light. This can lead to a surface-level distribution in the amount of OH radicals generated. Low OH radical generation efficiency or surface-level distribution in the amount of OH radicals generated can prevent proper processing of the substrate. Therefore, there has been a demand for the development of a substrate processing apparatus and a substrate processing method that can perform appropriate processing using a processing liquid containing OH radicals. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-311256 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a substrate processing apparatus and a substrate processing method that can perform appropriate processing using a processing liquid containing OH radicals. [Means for solving the problem]

[0008] The substrate processing apparatus and substrate processing method according to the embodiment include a mounting section that rotates a substrate placed on the mounting section, a nozzle that extends along the surface of the substrate, and a light source that irradiates ultraviolet light onto a raw material liquid flowing inside the nozzle. [Effects of the Invention]

[0009] According to the embodiments of the present invention, a substrate processing apparatus and a substrate processing method capable of performing appropriate processing using a processing liquid containing OH radicals are provided. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic view illustrating a substrate processing apparatus according to an embodiment of the present invention; [Figure 2] 2 is a schematic plan view of the substrate processing apparatus in FIG. 1 as viewed from the direction of line AA. [Figure 3] FIG. 2 is a schematic perspective view illustrating a treatment liquid generating and supplying unit. [Figure 4] 4 is a schematic perspective view of the processing liquid generating and supplying unit in FIG. 3 as viewed from direction B. FIG. [Figure 5]5 is a schematic perspective view of the treatment liquid generating and supplying unit in FIG. 4, with the cover and the light-shielding cover removed. FIG. [Figure 6] FIG. 2 is a schematic perspective view of the nozzle as viewed from the light source side. [Figure 7] 7 is a cross-sectional view of the nozzle taken along line CC in FIG. 6. [Figure 8] FIG. 2 is a schematic perspective view illustrating a lid. [Figure 9] 10(a) and 10(b) are schematic views illustrating a flow channel according to another embodiment. [Figure 10] 10A and 10B are schematic views illustrating flow channels according to other embodiments. [Figure 11] FIG. 10 is a schematic perspective view illustrating a nozzle according to another embodiment. [Figure 12] FIG. 12 is a schematic perspective view illustrating a case where a light-shielding cover is provided around the nozzle shown in FIG. 11. [Figure 13] 1 is a graph illustrating the generation of OH radicals by irradiation with ultraviolet rays. [Figure 14] 10 is a graph illustrating the resist removal effect of a treatment liquid containing OH radicals. [Figure 15] 10 is a graph illustrating the influence of a processing liquid containing OH radicals on a surface of a substrate. [Figure 16] 10 is a graph illustrating the effect of removing foreign matter by a treatment liquid containing OH radicals. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be illustrated with reference to the drawings. In the drawings, like components are designated by like reference numerals and detailed descriptions thereof will be omitted where appropriate. The substrate 100 exemplified below may be, for example, a semiconductor wafer, an imprint template, a photolithography mask, or a plate-like body used in MEMS (Micro Electro Mechanical Systems). The substrate 100 is not limited to the examples exemplified. The substrate 100 may be, for example, a substrate having a pattern (for example, fine concave and convex portions) formed on its surface, or may be a so-called bulk substrate.

[0012] FIG. 1 is a schematic view illustrating a substrate processing apparatus 1 according to the present embodiment. FIG. 2 is a schematic plan view of the substrate processing apparatus 1 in FIG. 1 as viewed from the direction of line AA. 2 illustrates a substrate 100 having a rectangular planar shape, but the planar shape of the substrate 100 is not limited to this. For example, the planar shape of the substrate 100 may be a circle. In addition, in FIG. 2, the processing liquid 5a supplied onto the surface 100a of the substrate 100 in FIG. 1 is not shown.

[0013] As shown in FIGS. 1 and 2, the substrate processing apparatus 1 includes, for example, a chamber 2, a mounting unit 3, a liquid supply unit 4, a processing liquid supply unit 5, and a controller 6.

[0014] The controller 6 includes a calculation unit such as a CPU (Central Processing Unit) and a storage unit such as a memory. The controller 6 may be, for example, a computer. The controller 6 controls the operation of each element provided in the substrate processing apparatus 1 based on a control program stored in the storage unit.

[0015] The chamber 2 is box-shaped. The chamber 2 has an airtight structure that prevents particles from entering the chamber 2 from the outside atmosphere. A cover 21 that surrounds the mounting unit 3 (mounting table 31) can be provided inside the chamber 2. The cover 21 receives the liquid 4a and processing liquid 5a (described later) that are supplied to the substrate 100 and then discharged outside the substrate 100 as the mounting table 31 on which the substrate 100 is placed rotates. The used liquid 4a and processing liquid 5a received by the cover 21 are discharged, for example, to factory piping via a discharge port 2a provided on the bottom side of the chamber 2.

[0016] The mounting section 3 rotates the mounted substrate 100. The mounting section 3 has, for example, a mounting table 31, a rotation shaft 32, and a drive section 33. The mounting table 31 is plate-shaped and rotatably provided inside the chamber 2. One main surface (mounting surface) of the mounting table 31 is provided with a plurality of supports 31a for supporting the substrate 100. When the substrate 100 is supported by the supports 31a, the surface 100a (surface to be processed) of the substrate 100 faces away from the mounting table 31. A hole 31b is provided in the center of the mounting table 31, penetrating the mounting table 31 in the thickness direction.

[0017] The rotating shaft 32 has a cylindrical shape. The end of the rotating shaft 32 on the side of the mounting table 31 is provided on the mounting table 31. The opening of a hole that passes through the rotating shaft 32 in the axial direction faces the back surface 100b of the substrate 100 placed on the mounting table 31. The end of the rotating shaft 32 opposite the side of the mounting table 31 can be provided outside the chamber 2.

[0018] The driving unit 33 is provided outside the chamber 2. The driving unit 33 is connected to the rotation shaft 32. The rotational force of the driving unit 33 is transmitted to the mounting table 31 via the rotation shaft 32. Therefore, the driving unit 33 can rotate the mounting table 31, and ultimately the substrate 100 mounted on the mounting table 31.

[0019] Furthermore, the driving unit 33 can not only start and stop rotation, but also change the number of rotations (rotation speed). The driving unit 33 can be equipped with a control motor such as a servo motor, for example.

[0020] The liquid supply unit 4 supplies a liquid 4 a to the rear surface 100 b of the substrate 100 placed on the mounting table 31 . The liquid supply unit 4 is provided, for example, to supply a liquid 4a that protects the back surface 100b of the substrate 100. For example, the liquid supply unit 4 prevents the processing liquid 5a supplied to the front surface 100a of the substrate 100 from flowing around to the back surface 100b of the substrate 100 and adhering to the back surface 100b of the substrate 100. In this case, there are no particular limitations on the liquid 4a as long as it is unlikely to react with the material of the substrate 100. The liquid 4a can be, for example, pure water.

[0021] The liquid supply unit 4 can also be provided for cleaning or processing the rear surface 100b of the substrate 100, for example. In this case, the liquid 4a can be, for example, a cleaning liquid or a processing liquid. The liquid 4a can be, for example, hydrogen peroxide water, ozone water, pure water, inorganic acid, inorganic alkali, organic acid, organic alkali, electrolyzed water, or a mixture of two or more of these. The liquid 4a can also be a liquid containing OH radicals, similar to the processing liquid 5a described below.

[0022] The liquid supply unit 4 can be provided as needed, for example, for protecting, cleaning, or processing the rear surface 100b of the substrate 100. Therefore, the liquid supply unit 4 is not necessarily required and can be omitted.

[0023] The liquid supply unit 4 has, for example, a liquid storage unit 41, a supply unit 42, a flow rate control unit 43, and a nozzle 44. The liquid storage unit 41, the supply unit 42, and the flow rate control unit 43 are provided outside the chamber 2.

[0024] The liquid storage section 41 stores the liquid 4a. The supply unit 42 is connected to the liquid storage unit 41 via a pipe. The supply unit 42 supplies the liquid 4a stored in the liquid storage unit 41 to the nozzle 44. The supply unit 42 can be, for example, a pump that is resistant to the liquid 4a.

[0025] The flow rate control unit 43 is connected to the supply unit 42 via a pipe. The flow rate control unit 43 controls the flow rate of the liquid 4a supplied by the supply unit 42. The flow rate control unit 43 can be, for example, a flow rate control valve. The flow rate control unit 43 can also start and stop the supply of the liquid 4a.

[0026] The nozzle 44 is provided inside the hole of the rotating shaft 32. The nozzle 44 can be provided, for example, near the end of the rotating shaft 32 on the side of the mounting table 31. One end of the nozzle 44 is connected to the flow rate control unit 43 via piping. The other end of the nozzle 44 is provided with an outlet. The outlet of the nozzle 44 faces the back surface 100b of the substrate 100 placed on the mounting table 31. The spray pattern of the nozzle 44 can be, for example, a flat pattern, a full cone pattern, a curtain pattern, or the like. The spray pattern of the nozzle 44 illustrated in FIG. 1 is a flat pattern or a full cone pattern.

[0027] The processing liquid supply unit 5 generates the processing liquid 5a and supplies the generated processing liquid 5a to the surface 100a of the substrate 100 placed on the mounting table 31. The processing liquid 5a can be a liquid containing OH radicals, which are active species.

[0028] The processing liquid supply unit 5 includes, for example, a raw material liquid storage unit 51, a supply unit 52, a flow rate control unit 53, a moving unit 54, and a processing liquid generation and supply unit 55. The raw material liquid storage unit 51, the supply unit 52, and the flow rate control unit 53 can be provided outside the chamber 2. The transfer unit 54 and the processing liquid generation and supply unit 55 can be provided inside the chamber 2.

[0029] The raw material liquid storage section 51 stores the raw material liquid used to generate the treatment liquid 5a. That is, the raw material liquid is used to generate a liquid containing OH radicals. The raw material liquid can be a liquid containing hydrogen atoms and oxygen atoms, such as ozone water, hydrogen peroxide water, or pure water. As will be described later, the treatment liquid 5a is generated by irradiating the raw material liquid with ultraviolet light. Therefore, in consideration of the efficiency of generating the treatment liquid 5a, the raw material liquid is preferably ozone water or hydrogen peroxide water, and more preferably ozone water.

[0030] The supply unit 52 is connected via a pipe to the raw material liquid storage unit 51. The supply unit 52 supplies the raw material liquid stored in the raw material liquid storage unit 51 to the processing liquid generation and supply unit 55. The supply unit 52 can be, for example, a pump that is resistant to the raw material liquid.

[0031] The inflow side of the flow rate control unit 53 is connected to the supply unit 52 via a pipe. The outflow side of the flow rate control unit 53 is connected to the processing liquid generation and supply unit 55 (nozzle 55d) via a pipe 53a. The pipe 53a may be a deformable pipe made of a fluororesin such as PFA. The flow rate control unit 53 controls the flow rate of the raw material liquid supplied by the supply unit 52 to the processing liquid generation and supply unit 55, and therefore the flow rate of the processing liquid 5a supplied from the processing liquid generation and supply unit 55 to the surface 100a of the substrate 100. The flow rate control unit 53 may be, for example, a flow control valve. The flow rate control unit 53 can also start and stop the supply of the raw material liquid and the processing liquid 5a.

[0032] The moving unit 54 moves the processing liquid generating and supplying unit 55, for example, in a direction substantially parallel to the surface 100a of the substrate 100. As described above, the mounting table 31 on which the substrate 100 is placed rotates, and therefore the moving speed (circumferential speed) of the surface 100a of the substrate 100 differs between the central region of the substrate 100 and the peripheral region of the substrate 100. Therefore, the amount of processing liquid 5a supplied per unit area is greater in the central region of the substrate 100 than in the peripheral region of the substrate 100. This makes it easier for processing unevenness to occur on the surface 100a of the substrate 100.

[0033] In this case, by moving the processing liquid generation and supply unit 55 in a direction approximately parallel to the surface 100a of the substrate 100, the variation in the amount of processing liquid 5a supplied per unit area can be reduced, and ultimately, processing unevenness on the surface 100a of the substrate 100 can be suppressed.

[0034] In this case, the processing liquid generating and supplying unit 55 may be moved along an arc-shaped trajectory or a linear trajectory in a plane substantially parallel to the surface 100a of the substrate 100. The moving unit 54 illustrated in Figures 1 and 2 oscillates the processing liquid generating and supplying unit 55 along an arc-shaped trajectory in a plane substantially parallel to the surface 100a of the substrate 100.

[0035] The moving unit 54 includes, for example, an arm 54a, a support 54b, and a driving unit 54c. For example, the arm 54a extends in one direction above the substrate 100 along the surface 100a. A portion near one end of the arm 54a is provided on a support 54b. The other end of the arm 54a is provided on the opposite side from the support 54b, across the rotation center 100c of the substrate 100 in plan view. A cover 54a1 can be provided on the end of the arm 54a opposite to the substrate 100 side.

[0036] The support pillar 54b extends in a direction approximately perpendicular to the surface 100a of the substrate 100 (the mounting surface of the mounting part 3). One end of the support pillar 54b can be provided above the substrate 100. The other end of the support pillar 54b can be provided near the bottom surface of the chamber 2.

[0037] The driving unit 54c may be provided inside the chamber 2 or outside the chamber 2. The driving unit 54c illustrated in Fig. 1 is provided on the bottom surface of the chamber 2. The driving unit 54c has a driving device such as a motor or an air cylinder.

[0038] In addition, when the processing liquid generating and supplying part 55 is moved along a linear trajectory, for example, a guide mechanism such as a linear bearing may be provided in place of the support column 54b.

[0039] The processing liquid generating and supplying unit 55 can be provided at the end of the arm 54a on the side of the mounting unit 3. FIG. FIG. 4 is a schematic perspective view of the processing liquid generating and supplying unit 55 in FIG. 3 as viewed from the direction B. FIG. 5 is a schematic perspective view of the treatment liquid generating and supplying unit 55 in FIG. 4, with the cover 54a1 and the light-shielding cover 55c omitted.

[0040] As shown in FIGS. 3 to 5, the treatment liquid generating and supplying unit 55 includes, for example, a holder 55a, a light source 55b, a light-shielding cover 55c, a nozzle 55d, and a lid 55e.

[0041] The holder 55a holds, for example, the light source 55b. The holder 55a can be attached to the end of the arm 54a on the substrate 100 side using, for example, a fastening member such as a screw. The holder 55a extends, for example, in the direction in which the arm 54a extends. Note that, for example, a plurality of holders 55a can be provided spaced apart from each other in the direction in which the arm 54a extends.

[0042] The light source 55b is provided on the opposite side of the nozzle 55d from the side where the multiple discharge ports 55da1 are opened. The light source 55b extends in the extension direction of the nozzle 55d. The light source 55b irradiates the raw material liquid flowing inside the nozzle 55d with ultraviolet light. The light source 55b irradiates, for example, ultraviolet light with a wavelength of approximately 200 nm to 350 nm. The light source 55b is, for example, rod-shaped and has a cylindrical shape with a circular cross section perpendicular to the longitudinal direction. The light source 55b can be, for example, a discharge lamp such as an excimer lamp. The light source 55b can also be, for example, a light-emitting element such as a light-emitting diode. When the light source 55b is a light-emitting element, a plurality of light-emitting elements can be arranged in the extension direction of the arm 54a.

[0043] The light-shielding cover 55c has, for example, a box shape and extends in the same direction as the arm 54a. The light source 55b, the lid 55e, and the nozzle 55d are housed inside the light-shielding cover 55c. As described above, the light source 55b emits ultraviolet light. Furthermore, as will be described later, the lid 55e and the nozzle 55d are made of a material that transmits ultraviolet light. Therefore, the light-shielding cover 55c is provided to prevent the ultraviolet light emitted from the light source 55b and the ultraviolet light that has been emitted from the light source 55b and transmitted through the lid 55e and the nozzle 55d from being irradiated outside the processing liquid generating and supplying unit 55. The light-shielding cover 55c can be made of a material that does not transmit ultraviolet light. The light-shielding cover 55c can be made of a metal such as stainless steel or an aluminum alloy, for example.

[0044] However, the surface of the light-shielding cover 55c facing the nozzle 55d is provided with holes 55c1 through which the treatment liquid 5a discharged from a plurality of outlets 55da1 of the nozzle 55d (described later) passes. The holes 55c1 are, for example, slit-shaped and extend in the direction in which the plurality of outlets 55da1 are arranged.

[0045] The light-shielding cover 55c can be attached to the arm 54a or the holder 55a using a fastening member such as a screw. In Figures 3 and 4, the light source 55b on the other end side of the arm 54a is not covered by the light-shielding cover 55c, but the end of the light source 55b may be covered by providing a surface that intersects the direction in which the arm 54a extends and is connected to the surface that extends in the direction in which the arm 54a extends.

[0046] The nozzle 55d is provided, for example, on the side opposite the arm 54a side of the light source 55b. The nozzle 55d is plate-shaped and extends along the surface 100a of the substrate 100 (the mounting surface of the mounting unit 3). The nozzle 55d is plate-shaped and has an outlet 55da extending in the direction in which the arm 54a extends and an inlet 55db which is a hole opening on the side of the outlet 55da. In the direction in which the outlet 55da extends, the inlet 55db is provided near the end of the outlet 55da. The inlet 55db is connected to the raw material liquid storage unit 51 via the pipe 53a and the flow rate control unit 53. The inlet 55db is provided to supply the raw material liquid to a flow path 55d1 of the nozzle 55d, which will be described later. The nozzle 55d (outlet 55da) is made of a material that transmits ultraviolet light, such as synthetic quartz glass.

[0047] FIG. 6 is a schematic perspective view of the nozzle 55d as viewed from the light source 55b side. FIG. 7 is a cross-sectional view of the nozzle 55d taken along line CC in FIG. As shown in FIGS. 6 and 7, a single flow path 55d1 through which the raw material liquid flows is provided inside the nozzle 55d. The flow path 55d1 opens to one surface of the nozzle 55d. The flow path 55d1 has, for example, a groove-like shape that is bent in a spiral shape. For example, the flow path 55d1 has a portion 55d1a extending in the direction in which the outflow portion 55da extends and a portion 55d1b extending in a direction intersecting the direction in which the outflow portion 55da extends. For example, a plurality of portions 55d1a may be provided. The portion 55d1b connects an end of one portion 55d1a to an end of the other portion 55d1a. The portion 55d1c connects an end of the one portion 55d1a to the inflow portion 55db.

[0048] One end of each flow path 55d1 is provided at the outlet 55da. In a direction intersecting the direction in which the outlet 55da extends, for example, one end of a portion 55d1a provided at approximately the center of the outlet 55da becomes one end 55d1d (terminal end) of each flow path 55d1. The other end of each flow path 55d1 is connected to the inlet 55db. For example, one end of a portion 55d1b connected to the inlet 55db becomes the other end 55d1e (terminal end) of each flow path 55d1.

[0049] 5 and 7, a plurality of outlets 55da1 are connected to a flow path 55d1 (portion 55d1a) provided substantially in the center of the outlet portion 55da. That is, the plurality of outlets 55da1 are connected to the flow path 55d1 provided substantially in the center of the nozzle 55d (outlet portion 55da) in a direction intersecting the direction in which the nozzle 55d extends. The plurality of outlets 55da1 open to a surface of the nozzle 55d (outlet portion 55da) opposite to the side on which the flow path 55d1 opens (the surface facing the front surface 100a of the substrate 100). The plurality of outlets 55da1 are arranged side by side in the direction in which the nozzle 55d (outlet portion 55da) extends.

[0050] The processing liquid 5a generated inside the flow path 55d1 of the nozzle 55d is supplied to the surface 100a of the substrate 100 through a plurality of discharge ports 55da1. The number, arrangement, diameter, etc. of the plurality of discharge ports 55da1 can be changed as appropriate depending on the size of the substrate 100, the required flow rate of the processing liquid 5a, etc. The production of the treatment liquid 5a will be described in detail later.

[0051] FIG. 8 is a schematic perspective view illustrating the lid 55e. As shown in FIG. 8, the lid 55e is plate-shaped and covers the surface of the nozzle 55d on the side where the flow path 55d1 opens.

[0052] The planar shape of the lid 55e can be the same as the planar shape of the nozzle 55d. The lid 55e can be attached to the nozzle 55d using a fastening member such as a screw, or can be glued to the nozzle 55d. The lid 55e is made of a material that transmits ultraviolet light, such as synthetic quartz glass.

[0053] Next, the generation of the processing liquid 5a and the processing of the substrate 100 using the processing liquid 5a will be described. First, the raw material liquid such as ozone water stored in the raw material liquid storage unit 51 is supplied by the supply unit 52 and the flow rate control unit 53 to the flow path 55d1 of the processing liquid 5a. Furthermore, ultraviolet light is irradiated from light source 55b toward nozzle 55d. The ultraviolet light irradiated from light source 55b passes through lid 55e and is irradiated onto the raw material liquid flowing inside flow path 55d1. Furthermore, since nozzle 55d (outlet portion 55da) is also formed from a material that transmits ultraviolet light, ultraviolet light incident on nozzle 55d (outlet portion 55da) is irradiated onto the raw material liquid flowing inside flow path 55d1 from, for example, a side wall of flow path 55d1. Therefore, if nozzle 55d (outlet portion 55da) is formed from a material that transmits ultraviolet light, the utilization efficiency of ultraviolet light irradiated from light source 55b can be improved.

[0054] As described above, the OH radicals are generated by irradiating the raw material liquid with ultraviolet light from the light source 55b through the nozzle 55d (lid 55e). Although it is possible to bring the raw material liquid into direct contact with the light source 55b and irradiate it with ultraviolet light, irradiating the raw material liquid with ultraviolet light through the nozzle 55d makes it possible to generate the processing liquid 5a containing OH radicals without mixing particles resulting from dust generation from the light source 55b into the raw material liquid.

[0055] The raw material liquid flowing inside one flow path 55d1 is irradiated with ultraviolet rays, thereby generating a processing liquid 5a containing OH radicals. For example, when the raw material liquid is irradiated with ultraviolet rays, the raw material liquid is decomposed to generate OH radicals. As a result, the processing liquid 5a containing OH radicals is generated from the raw material liquid. The generated processing liquid 5a is supplied to the surface 100a of the substrate 100 through multiple discharge ports 55da1 provided in the nozzle 55d. When the processing liquid 5a containing OH radicals is supplied to the surface 100a of the substrate 100, particles, organic matter, etc. adhering to the surface 100a of the substrate 100 are decomposed and removed.

[0056] As described above, the nozzle 55d extends along the surface 100a of the substrate 100 (in a direction parallel to the surface 100a of the substrate 100). The source liquid flowing through the nozzle 55d is irradiated with ultraviolet light from the ultraviolet light source 55b. Therefore, compared to when the nozzle 55d extends in a direction perpendicular to the surface 100a of the substrate 100, the effect of gravity on the flow velocity of the source liquid flowing through the nozzle 55d can be reduced. The reduced effect of gravity on the flow velocity of the source liquid makes it easier to control the flow velocity of the source liquid by the supply pressure of the source liquid. In this case, by controlling the supply pressure of the source liquid to slow the flow velocity of the source liquid, the residence time of the source liquid in the flow path 55d1 along the light source 55b can be increased, thereby increasing the cumulative amount of ultraviolet light irradiated onto the source liquid. Therefore, the processing liquid 5a containing OH radicals can be efficiently generated.

[0057] As described above, the single flow path 55d1 provided in the nozzle 55d has a curved shape. Therefore, the overall length of the flow path 55d1 can be increased, thereby lengthening the time the raw material liquid passes through the flow path 55d1 and thereby increasing the cumulative amount of ultraviolet light irradiated onto the raw material liquid. This allows the processing liquid 5a containing OH radicals to be efficiently generated. The overall length and cross-sectional dimensions of the flow path 55d1 can be appropriately changed depending on the size of the substrate 100, the required flow rate of the processing liquid 5a, and the like.

[0058] As described above, the processing liquid 5a containing the generated OH radicals is supplied to the surface 100a of the substrate 100 through the multiple outlets 55da1. The multiple outlets 55da1 are aligned in the direction in which the nozzles 55d extend. Therefore, as shown in FIG. 1, the processing liquid 5a can be supplied simultaneously to a wide area of ​​the surface 100a of the substrate 100.

[0059] Here, OH radicals are easily deactivated. Therefore, for example, when a processing solution 5a containing OH radicals is supplied onto the surface 100a of the substrate 100 from one discharge port 55da1, the concentration of OH radicals will differ directly below the discharge port 55da1 and at a position distant from the discharge port 55da1. More specifically, on the surface 100a of the substrate 100, OH radicals are more likely to be deactivated at a position distant from the discharge port 55da1 than at a position directly below the discharge port 55da1, resulting in a lower concentration of OH radicals in the processing solution 5a and a weaker removal effect of organic matter, etc. Therefore, an in-plane distribution of the removal effect of organic matter, etc. is likely to occur.

[0060] 1, if the processing liquid 5a containing OH radicals is supplied from a plurality of outlets 55da1 to the surface 100a of the substrate 100, it is possible to prevent the concentration of OH radicals from being unevenly distributed on the surface 100a of the substrate 100. Therefore, it is possible to prevent the removal effect of organic substances and the like from being unevenly distributed on the surface.

[0061] Furthermore, since OH radicals are easily deactivated as described above, it is preferable to set the distance L between the nozzle 55d and the surface 100a of the substrate 100 to 12 mm or less, as shown in Figure 1. This makes it possible to suppress the deactivation of OH radicals, thereby improving the efficiency of removing organic matter and the like.

[0062] Furthermore, the processing liquid 5a supplied to the surface 100a of the substrate 100 is discharged to the outside of the substrate 100 as the substrate 100 rotates. Therefore, the residence time of the processing liquid 5a supplied to the peripheral region of the substrate 100 is shorter than the residence time of the processing liquid 5a supplied to the central region of the substrate 100. Therefore, the flow rate of the processing liquid 5a supplied to the peripheral region of the substrate 100 can be made greater than the flow rate of the processing liquid 5a supplied to the central region of the substrate 100. For example, the pitch dimension of the discharge ports 55da1 facing the peripheral region of the substrate 100 can be made shorter than the pitch dimension of the discharge ports 55da1 facing the central region of the substrate 100. Furthermore, for example, the opening area of ​​the discharge ports 55da1 facing the peripheral region of the substrate 100 can be made larger than the opening area of ​​the discharge ports 55da1 facing the central region of the substrate 100.

[0063] 9(a) and 9(b) are schematic views illustrating flow channels 155d1 and 255d1 according to another embodiment. As shown in FIG. 9(a), one flow path 155d1 has a meandering shape in the direction in which the outflow portion 55da extends. As shown in FIG. 9(b), one flow path 255d1 has a shape that meanders in a direction that intersects with the direction in which the outflow portion 55da extends.

[0064] Even in this case, the total length of each flow path 155d1, 255d1 can be increased, which in turn increases the time the raw material liquid passes through the flow path 155d1, 255d1, thereby increasing the cumulative amount of ultraviolet light irradiated onto the raw material liquid, thereby efficiently producing the treatment liquid 5a containing OH radicals.

[0065] However, as shown in FIG. 6, if a single flow path 55d1 has a curved shape like a spiral, multiple outlets 55da1 can be provided in flow path 55d1 (portion 55d1a) provided approximately in the center of outflow portion 55da. In this case, as shown in FIG. 5, light source 55b faces flow path 55d1 (portion 55d1a) provided approximately in the center of outflow portion 55da. Light source 55b has a cylindrical shape and extends in the direction of extension of nozzle 55d (outflow portion 55da). The axial center of light source 55b is positioned in a region facing approximately the center of outflow portion 55da. Therefore, the distance between flow path 55d1 (portion d1a) provided approximately in the center of outflow portion 55da and the surface (irradiation surface) of light source 55b can be reduced. This increases the illuminance of ultraviolet light irradiated onto the flow path 55d1 (portion 55d1a) provided with the plurality of outlets 55da1, thereby increasing the efficiency of generating OH radicals and increasing the concentration of OH radicals contained in the processing liquid 5a immediately before it is supplied to the surface 100a of the substrate 100. If the concentration of OH radicals contained in the processing liquid 5a immediately before it is supplied to the surface 100a of the substrate 100 can be increased, the efficiency of removing organic matter and the like can be improved.

[0066] FIG. 10 is a schematic view illustrating a flow path 355d1 according to another embodiment. The dimension of the flow path 355d1 shown in FIG. 10 in a direction perpendicular to the direction in which the outflow portion 55da extends can be made larger than the width dimension of the light source 55a, for example. 10, the volume of the portion of the flow path 355d1 extending in the direction of the outflow portion 55da can be increased. This increases the time the raw material liquid remains in the flow path 355d1, thereby increasing the cumulative amount of ultraviolet light irradiated onto the raw material liquid. As a result, the treatment liquid 5a containing OH radicals can be efficiently produced.

[0067] FIG. 11 is a schematic perspective view illustrating a nozzle 455d according to another embodiment. As shown in FIG. 11, the nozzle 455d has a tubular shape. The inside of the tubular nozzle 455d serves as a flow path 455d1 through which the raw material liquid flows. Nozzle 455d has a portion facing light source 55b, and the facing portion extends along light source 55b. The portion of nozzle 455d facing light source 55b is made of a material that transmits ultraviolet light, such as synthetic quartz glass. Therefore, ultraviolet light emitted from light source 55b is incident on the raw material liquid flowing through flow path 455d1 inside nozzle 455d. When the raw material liquid flowing through flow path 455d1 is irradiated with ultraviolet light, processing liquid 5a containing OH radicals is generated.

[0068] One end of the nozzle 455d is connected to the pipe 53a. The pipe 53a may be a deformable pipe made of a fluororesin such as PFA. The other end of the nozzle 455d is open. The processing liquid 5a is generated by irradiating the raw material liquid flowing inside the nozzle 455d (flow path 455d1) with ultraviolet light, and is supplied to the surface 100a of the substrate 100 from the opening 455da of the nozzle 455d. By supplying the processing liquid 5a containing OH radicals to the surface 100a of the substrate 100, particles, organic matter, and the like adhering to the surface 100a of the substrate 100 are decomposed and removed.

[0069] As described above, in this embodiment, deformable pipe 53a is connected to one end of tubular nozzle 455d. Therefore, compared to the plate-shaped nozzle 55d having a flow path therein, the location of nozzle 455d (flow path 455d1) can be freely selected.

[0070] In addition, it is possible to increase the linear distance of flow path 455d1 through which ultraviolet light from light source 55b is incident. If the flow path 455d1 extends linearly, it is possible to prevent the generated OH radicals from colliding with the curved flow path and becoming inactivated, which makes it easier to supply the processing solution 5a containing OH radicals to the surface 100a of the substrate 100. Furthermore, if the linear distance of the flow path 455d1 is long, the amount of OH radicals produced can be increased.

[0071] It is also possible to bring the raw material liquid into direct contact with the light source 55b and directly irradiate the raw material liquid with ultraviolet light, but this may result in particles generated by the light source 55b being mixed into the raw material liquid. Irradiating the raw material liquid with ultraviolet light through the nozzle 455d can prevent particles generated by the light source 55b from being mixed into the raw material liquid, thereby allowing the processing liquid 5a without foreign matter to be supplied to the surface 100a of the substrate 100.

[0072] Furthermore, nozzle 455d extends along surface 100a of substrate 100 (in a direction parallel to surface 100a of substrate 100). Therefore, the effect of gravity on the flow rate of the raw material liquid flowing through flow path 455d1 inside nozzle 455d can be reduced compared to when nozzle 455d extends in a direction perpendicular to surface 100a of substrate 100. If the effect of gravity on the flow rate of the raw material liquid is reduced, it becomes easier to control the flow rate of the raw material liquid by the supply pressure.

[0073] In this case, by controlling the supply pressure of the raw material liquid to slow down the flow rate of the raw material liquid, the residence time of the raw material liquid in the flow path 455d1 along the light source 55b can be increased, and the integrated amount of ultraviolet light irradiated onto the raw material liquid can be increased, thereby making it possible to efficiently generate the treatment liquid 5a containing OH radicals.

[0074] In FIG. 11, nozzle 455d is positioned so that the raw material liquid flows from the other end side of arm 54a toward support 54b side of arm 54a, but nozzle 455d may also be positioned so that the raw material liquid flows from the support 54b side of arm 54a toward the other end side of arm 54a. As long as the opening 455da of the nozzle 455d is positioned above the center of the substrate 100, there is no particular limitation on the arrangement of the nozzle 455d.

[0075] FIG. 12 is a schematic perspective view illustrating a case where a light-shielding cover 55c is provided around the nozzle 455d shown in FIG. 12, a light-shielding cover 55c can be provided to surround the light source 55b. The provision of the light-shielding cover 55c can prevent ultraviolet light emitted from the light source 55b and ultraviolet light emitted from the light source 55b and transmitted through the nozzle 455d from being irradiated outside the treatment liquid generating and supplying unit 55.

[0076] Furthermore, a hole 55c2 through which the processing liquid 5a discharged from the opening 455da of the nozzle 455d passes can be provided on the surface of the light-shielding cover 55c facing the nozzle 455d and facing the surface 100a of the substrate 100. The size of the hole 55c2 can be larger than the size of the opening 455da of the nozzle 455d, for example. 12, the surface facing the nozzle 455d and the surface facing the surface 100a of the substrate 100 may be omitted. In this case, the light-shielding cover 55c is configured by a side wall surrounding the light source 55b provided so as to intersect with the direction extending along the arm 54a, and the portion facing the surface 100a of the substrate 100 is open. The light source 55b and the opening 455da of the nozzle 455d are exposed from this opening.

[0077] FIG. 13 is a graph illustrating the generation of OH radicals by irradiation with ultraviolet rays. C1 in Figure 13 is the case where ozone water is not irradiated with ultraviolet rays. In this case, ozone decomposition (production of OH radicals) due to ultraviolet irradiation does not occur, so there is no change in the ozone concentration.

[0078] C2 in Figure 13 shows the case where ozone water is irradiated with ultraviolet light in the wavelength range of 200 nm to 350 nm. In this case, the ozone is decomposed by the ultraviolet light irradiation, generating OH radicals. Therefore, as the irradiation time elapses, the ozone concentration decreases, and the OH radical concentration increases accordingly. In other words, the OH radical concentration is positively correlated with the integrated amount of ultraviolet light. Therefore, if the relationship between the concentration of OH radicals and the integrated amount of ultraviolet light is found through experiments or simulations, it is possible to set, for example, the overall length and cross-sectional area of ​​the single flow path 55d1 described above.

[0079] Fig. 14 is a graph illustrating the resist removal effect of the treatment liquid 5a containing OH radicals, ie, Fig. 14 is an example of the organic matter removal effect of the treatment liquid 5a containing OH radicals.

[0080] 14, C1a is the case where the ozone water is not irradiated with ultraviolet light, that is, the resist is removed by the oxidizing action of the ozone water.

[0081] 14 shows the case where ozone water is irradiated with ultraviolet light having a wavelength range of 200 nm to 350 nm, that is, the case where the resist is removed by the processing liquid 5a containing OH radicals. As can be seen from C1a in Fig. 14, the resist can be removed using ozone water. However, as can be seen from C2a in Fig. 14, the resist removal efficiency can be significantly improved by using the treatment liquid 5a containing OH radicals.

[0082] FIG. 15 is a graph illustrating the influence of the processing liquid 5a containing OH radicals on the surface 100a of the substrate 100. In FIG.

[0083] C1b in Fig. 15 is the case where the ozone water is not irradiated with ultraviolet rays, that is, it represents the amount of oxidation (amount of oxidation of silicon) on the surface 100a of the substrate 100 due to the oxidizing action of the ozone water.

[0084] 15 shows the case where ozone water is irradiated with ultraviolet light in the wavelength range of 200 nm to 350 nm, ie, the amount of oxidation of surface 100a of substrate 100 (amount of oxidation of silicon) caused by OH radicals. As can be seen from FIG. 15, when the processing liquid 5a containing OH radicals is used, the amount of oxidation on the surface 100a of the substrate 100 can be suppressed more effectively than when ozone water is used.

[0085] That is, as can be seen from Figures 14 and 15, using a processing liquid 5a containing OH radicals can improve the efficiency of removing organic matter compared to using ozone water, and can also suppress damage to the surface 100a of the substrate 100.

[0086] FIG. 16 is a graph illustrating the effect of removing foreign matter by the treatment liquid 5a containing OH radicals. If foreign matter such as particles adheres to the surface 100a of the substrate 100, the contact angle of the surface 100a of the substrate 100 increases. Furthermore, the higher the degree of cleanliness of the surface 100a of the substrate 100, the smaller the contact angle of the surface 100a of the substrate 100.

[0087] 16, supplying the processing liquid 5a containing OH radicals to the surface 100a of the substrate 100 can reduce the contact angle of the surface 100a of the substrate 100. In other words, supplying the processing liquid 5a containing OH radicals to the surface 100a of the substrate 100 can remove (clean) foreign matter such as particles adhering to the surface 100a of the substrate 100.

[0088] Next, a substrate processing method according to this embodiment will be illustrated. In the substrate processing method according to this embodiment, the substrate 100 is processed as follows. First, ultraviolet light is irradiated onto the raw material liquid flowing inside the flow path 55d1 provided inside the nozzle 55d to generate the processing liquid 5a containing OH radicals. The generated processing liquid 5a is then supplied onto the surface 100a of the substrate 100 via a plurality of discharge ports 55da1 that communicate with the flow path 55d1.

[0089] In this case, the plurality of outlets 55da1 are arranged on the surface 100a of the substrate 100 in a row substantially parallel to one another. The specific details of the substrate processing method can be the same as those described above, and therefore a detailed description thereof will be omitted.

[0090] Although the embodiments have been described above, the present invention is not limited to these descriptions. With respect to the above-described embodiments, those skilled in the art may add, delete, or modify components as appropriate, or add, omit, or change processes or conditions as appropriate, and these modifications are also within the scope of the present invention as long as they retain the characteristics of the present invention.

[0091] For example, the shape, size, material, arrangement, etc. of each element included in the substrate processing apparatus 1 are not limited to those exemplified, and can be changed as appropriate. Furthermore, the elements of each of the above-described embodiments can be combined to the greatest extent possible, and such combinations are also included within the scope of the present invention as long as they include the features of the present invention. [Explanation of symbols]

[0092] 1 substrate processing apparatus, 3 placement section, 5 processing liquid supply section, 5a processing liquid, 51 raw material liquid storage section, 52 supply section, 53 flow rate control section, 54 moving section, 55 processing liquid generation and supply section, 55b light source, 55d nozzle, 55d1 flow path, 55da outflow section, 55da1 discharge port, 55db inflow section, 100 substrate, 100a surface

Claims

1. a mounting unit that rotates a mounted substrate; a nozzle extending along a surface of the substrate; a light source that irradiates ultraviolet light onto the raw material liquid flowing inside the nozzle; A substrate processing apparatus comprising:

2. The nozzle has a plate shape, a single flow path provided inside the nozzle, having a curved shape, through which the raw material liquid flows; a plurality of discharge ports, one end of which communicates with the flow path and the other end of which opens onto a surface of the nozzle facing the surface of the substrate, the discharge ports being arranged in a direction in which the nozzle extends; The substrate processing apparatus according to claim 1 , further comprising:

3. 3. The substrate processing apparatus according to claim 2, wherein the raw material liquid flowing inside the single flow path is irradiated with ultraviolet light to generate a processing liquid containing OH radicals, and the generated processing liquid is supplied to the surface of the substrate through the multiple outlets.

4. 4. The substrate processing apparatus according to claim 2, wherein the light source is provided on a side of the nozzle opposite to a side on which the plurality of discharge ports are opened, and extends in the same direction as the nozzle.

5. 4. The substrate processing apparatus according to claim 2, wherein the plurality of discharge ports are in communication with the flow path provided at approximately the center of the nozzle in a direction intersecting the direction in which the nozzle extends.

6. UV light is irradiated onto the raw material liquid flowing through a flow path provided inside the nozzle to generate a treatment liquid containing OH radicals; The method for processing a substrate includes supplying the generated processing liquid to the surface of the substrate through a plurality of discharge ports that communicate with the flow path.

7. 7. The substrate processing method according to claim 6, wherein the plurality of discharge ports are arranged substantially parallel to the surface of the substrate.

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