Substrate processing method and substrate processing apparatus

Abstract

To provide a substrate processing method and a substrate processing apparatus capable of reducing substrate defects.SOLUTION: A substrate processing method according to an embodiment includes forming a liquid film on a substrate having a first region where a first film is provided on the outermost surface and a second region where a second film made of a different material from the first film is provided on the outermost surface, forming a coagulated film by coagulating the liquid film, and melting the coagulated film on the first region before the coagulated film on the second region.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] FIELD Embodiments of the present invention relate to a substrate processing method and a substrate processing apparatus. [Background technology]

[0002] In freeze cleaning, which involves freezing a cleaning solution supplied onto a photomask substrate to remove foreign matter from the substrate, defects such as partial oxidation of the substrate may occur. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-8040 Summary of the Invention [Problem to be solved by the invention]

[0004] A substrate processing method and a substrate processing apparatus capable of reducing defects in substrates are provided. [Means for solving the problem]

[0005] According to one embodiment, a substrate processing method includes forming a liquid film on a substrate having a first region having a first film formed on its outermost surface and a second region having a second film formed on its outermost surface, the second region being made of a material different from that of the first film. The method further includes solidifying the liquid film to form a solidified film. The method further includes melting the solidified film on the first region prior to melting the solidified film on the second region. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing an example of a substrate processing apparatus according to a first embodiment. [Figure 2] 1 is a plan view showing an example of a substrate to be processed in the substrate processing apparatus according to the first embodiment. [Figure 3]1 is a cross-sectional view showing an example of a substrate to be processed in the substrate processing apparatus according to the first embodiment. [Figure 4] 5 is a flowchart showing an example of operation of the substrate processing apparatus according to the first embodiment. [Figure 5] 5 is a timing chart showing an example of operation of the substrate processing apparatus according to the first embodiment. [Figure 6] 5A to 5C are cross-sectional views showing an example of operation of the substrate processing apparatus according to the first embodiment. [Figure 7] 4 is a plan view showing an example of operation of the substrate processing apparatus according to the first embodiment. FIG. [Figure 8] 7A to 7C are cross-sectional views showing an example of operation of the substrate processing apparatus according to the first embodiment, following FIG. [Figure 9] 10A and 10B are cross-sectional views showing an example of operation of the substrate processing apparatus according to the first modified example of [Figure 10] FIG. 10 is a view showing a substrate processing apparatus according to a second modified example of the first embodiment. [Figure 11] FIG. 10 is a plan view showing a part of the substrate processing apparatus 1 according to a second modified example of the first embodiment. [Figure 12] 10 is a timing chart showing the operation of the substrate processing apparatus according to the second modified example of the first embodiment. [Figure 13] FIG. 10 is a cross-sectional view showing an example of operation of the substrate processing apparatus according to the second modified example of the first embodiment [Figure 14] FIG. 10 is a diagram showing an example of a substrate processing apparatus according to a second embodiment. [Figure 15] 10 is a timing chart showing an example of the operation of the substrate processing apparatus according to the second embodiment. [Figure 16] 10A and 10B are diagrams illustrating an example of the operation of the substrate processing apparatus according to the second embodiment. [Figure 17] FIG. 10 is a view showing a substrate processing apparatus according to a first modified example of the second embodiment. [Figure 18] 10 is a timing chart showing the operation of the substrate processing apparatus according to a first modified example of the second embodiment. [Figure 19] FIG. 10 is a view showing a substrate processing apparatus according to a second modified example of the second embodiment. [Figure 20]10 is a timing chart showing the operation of the substrate processing apparatus according to the second modified example of the second embodiment. [Figure 21] 10 is a timing chart showing the operation of the substrate processing apparatus according to the third modified example of the second embodiment. [Figure 22] FIG. 10 is a view showing a substrate processing apparatus according to a fourth modified example of the second embodiment. [Figure 23] 10 is a timing chart showing the operation of the substrate processing apparatus according to a fourth modified example of the second embodiment. [Figure 24] 10 is a timing chart showing the operation of the substrate processing apparatus according to the fifth modified example of the second embodiment. [Figure 25] FIG. 10 is a diagram showing an example of a substrate processing apparatus according to a third embodiment. [Figure 26] FIG. 10 is a plan view showing a part of a substrate processing apparatus according to a third embodiment. [Figure 27] FIG. 11 is a view showing a substrate processing apparatus according to a first modified example of the third embodiment. [Figure 28] FIG. 11 is an explanatory view for explaining the operation of the substrate processing apparatus according to a first modified example of the third embodiment. [Figure 29] FIG. 11 is a plan view of a part of the substrate processing apparatus according to a second modified example of the third embodiment. [Figure 30] FIG. 11 is a block diagram showing a substrate processing apparatus according to a third modified example of the third embodiment. [Figure 31] FIG. 10 is a view showing a substrate processing apparatus according to a fourth modified example of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to the embodiment.

[0008] (First embodiment) FIG. 1 is a diagram illustrating an example of a substrate processing apparatus 1 according to a first embodiment. In this specification, the vertical direction is defined as the Z-axis direction, the horizontal direction as the X-axis direction, and the horizontal direction perpendicular to the X-axis direction as the Y-axis direction. In this specification, "upward" refers to the positive Z-axis direction, and "downward" refers to the negative Z-axis direction. The substrate processing apparatus 1 is configured to perform freeze cleaning, which freezes a cleaning solution supplied to a photomask substrate 2 to remove foreign matter from the substrate 2. Specifically, as shown in FIG. 1, the substrate processing apparatus 1 includes a stage 101, a processing solution nozzle 103, a processing solution supply unit 105, a cooling gas supply unit 107, a processing solution nozzle moving device 108, a rotation driver 109, a layout information acquisition unit 111, a control unit 113, a temperature sensor 117, a cup 119, and a housing 121.

[0009] Before describing the substrate processing apparatus 1 in detail, the substrate 2 will be described. FIG. 2 is a plan view showing an example of the substrate 2 processed by the substrate processing apparatus 1 according to the first embodiment. FIG. 3 is a cross-sectional view showing an example of the substrate 2 processed by the substrate processing apparatus 1 according to the first embodiment. FIG. 3 is a cross-sectional view taken along III-III in FIG. 2. In the example shown in FIGS. 2 and 3, the substrate 2 is a substrate for a halftone phase shift mask that improves pattern resolution by utilizing a phase shift that attenuates the intensity of transmitted light while inverting the phase by 180°. The substrate 2 may also be a substrate for a photomask other than a halftone phase shift mask.

[0010] As shown in Figures 2 and 3, the substrate 2 has a first substrate region 21 having a light-shielding film 203 provided on its outermost surface, and a second substrate region 22 having a half-tone film 202 made of a different material from the light-shielding film 203 provided on its outermost surface. In the example shown in Figure 2, the first substrate region 21 is a region on the outer periphery (i.e., peripheral side) of the substrate 2. The second substrate region 22 is a region on the central side of the substrate 2. More specifically, in the example shown in Figure 2, the second substrate region 22 is a region having a rectangular shape in a planar view. The first substrate region 21 surrounds the second substrate region 22 and is a region having a rectangular frame shape in a planar view.

[0011] More specifically, the substrate 2 includes a quartz substrate 201, a half-tone film 202, and a light-shielding film 203. The quartz substrate 201 has a rectangular shape in a plan view. The quartz substrate 201 contains quartz (Qz). The half-tone film 202 is formed on the surface (i.e., the upper surface) of the quartz substrate 201. The half-tone film 202 contains, for example, at least silicon (Si) and may further contain molybdenum (Mo) or nitrogen (N). The half-tone film 202 contains, for example, molybdenum silicide (MoSi). The half-tone film 202 inverts the phase of light passing through it by 180° relative to a portion where the half-tone film 202 is absent and the quartz substrate 201 is exposed. The half-tone film 202 in the second substrate region 22 is partitioned into multiple regions via dicing lines 2021. For example, different patterns (not shown) may be formed in each partition, or similar patterns may be formed in each partition. The light-shielding film 203 is formed, for example, on the surface of the half-tone film 202 in the first substrate region 21. The light-shielding film 203 is not formed, for example, on the surface of the half-tone film 202 in the second substrate region 22. In this case, the first substrate region 21 has the light-shielding film 203 on its outermost surface, and the second substrate region 22 has the half-tone film 202 on its outermost surface. The light-shielding film 203 has a rectangular frame shape in a plan view. The light-shielding film 203 contains chromium (Cr). The light-shielding film 203 blocks light. Note that the first substrate region 21 may be a region in which a portion of the light-shielding film 203 on its outermost surface includes a film other than the light-shielding film 203 (for example, an alignment mark) at a significantly smaller area ratio than the light-shielding film 203.

[0012] Next, the substrate processing apparatus 1 will be described in detail. As shown in Fig. 1, a stage 101 is disposed in a housing 121, and a substrate 2 can be placed on the stage 101. Note that the substrate 2 is shown in a simplified form in Fig. 1. The stage 101 holds the placed substrate 2.

[0013] More specifically, as shown in FIG. 1, the stage 101 is formed in a disk shape and has a horizontal surface. Four substrate support pins 102 are arranged on the outer periphery of the surface of the stage 101 so as to correspond to the four corners of the rectangular substrate 2. The substrate support pins 102 support the four corners of the substrate 2, thereby supporting the substrate 2 horizontally on the stage 101. The substrate support pins 102 are conductive so that the light-shielding film 203 can be efficiently neutralized. The substrate support pins 102 may be made of, for example, conductive PEEK (polyether ether ketone).

[0014] More specifically, the stage 101 is fixed concentrically to the upper end of a rotation shaft 104 extending in the vertical direction (Z-axis direction). The stage 101 can rotate around the rotation shaft 104, for example, in the rotation direction indicated by arrow A in FIG. 1 . A rotation drive unit 109 is connected to the rotation shaft 104. The rotation drive unit 109 has, for example, an actuator such as a motor. The rotation drive unit 109 rotates the rotation shaft 104 and the stage 101 on the rotation shaft 104 under the control of a control unit 113. Rotating the stage 101 can promote the formation of a liquid film of a cleaning liquid on the outermost surface of the substrate 2, which will be described later.

[0015] 1, a substantially cylindrical cup 119 is provided around the stage 101 and is concentric with the stage 101. The upper end of the cup 119 is positioned higher than the surface of the substrate 2. The cup 119 prevents the cleaning liquid on the surface of the substrate 2 from scattering around due to the rotation of the stage 101 during freeze cleaning.

[0016] The processing liquid nozzle 103 is configured to form a liquid film of the processing liquid on the substrate 2 (i.e., on the outermost surface of the substrate 2). The processing liquid is, for example, pure water. Specifically, the processing liquid nozzle 103 is connected to a processing liquid supply unit 105 via a supply pipe 106. The processing liquid supply unit 105 supplies the processing liquid to the processing liquid nozzle 103 through the supply pipe 106. The processing liquid supply unit 105 includes, for example, a storage tank that stores the processing liquid, a pump that supplies the processing liquid from the storage tank to the processing liquid nozzle 103, and a valve that adjusts the flow rate of the supplied processing liquid. The control unit 113 controls the flow rate of the processing liquid supplied by the processing liquid supply unit 105. The processing liquid nozzle 103 forms a liquid film of the processing liquid on the substrate 2 by ejecting the processing liquid supplied by the processing liquid supply unit 105 onto the substrate 2.

[0017] A processing liquid nozzle moving device 108 is connected to the processing liquid nozzle 103. The processing liquid nozzle moving device 108 moves the processing liquid nozzle 103 from a standby position to a processing liquid discharge position (hereinafter referred to as a second discharge position) for forming a liquid film, for example, under the control of the control unit 113. The second discharge position is, for example, a position facing the rotation center of the substrate 2 in the second substrate region 22. Discharging the processing liquid at a position facing the rotation center of the substrate 2 can further promote the formation of a liquid film accompanying the rotation of the substrate 2. The processing liquid nozzle moving device 108 may have, for example, an arm connected to the processing liquid nozzle 103 and a drive source such as a motor connected to the arm.

[0018] The cooling gas supply unit 107 is configured to solidify the liquid film of the processing liquid formed on the substrate 2 to form a solidified film. The solidified film is, for example, ice obtained by freezing pure water. Specifically, the cooling gas supply unit 107 supplies cooling gas to the rear surface of the substrate 2 through a cooling gas nozzle 1041 provided vertically penetrating the center of the rotation shaft 104. The cooling gas is, for example, nitrogen (N2) gas. The cooling gas supply unit 107 includes, for example, a storage tank for storing liquefied cooling gas and a valve for adjusting the flow rate of the cooling gas supplied from the storage tank to the cooling gas nozzle 1041. The control unit 113 controls the flow rate of the cooling gas supplied by the cooling gas supply unit 107. For example, the control unit 113 continues the supply of cooling gas until a solidified film is formed based on the temperature measurement result of the substrate 2 by a temperature sensor 117 provided in the processing liquid nozzle 103. The cooling gas nozzle 1041 discharges the cooling gas supplied from the cooling gas supply unit 107 onto the rear surface of the substrate 2, thereby solidifying the liquid film of the processing liquid formed on the substrate 2 and forming a solidified film. By forming the solidified film, foreign matter attached to the surface of the substrate 2 can be lifted (separated) from the surface due to volume expansion caused by the change of the processing liquid from the liquid phase to the solid phase. By lifting the foreign matter, the foreign matter can be effectively removed from the substrate 2 after the solidified film 204 melts. Furthermore, by performing such freeze cleaning, even when the critical dimension (CD) of the pattern formed in the halftone film 202 is small, the foreign matter can be appropriately removed while preventing the pattern from collapsing and the optical properties from changing.

[0019] The processing liquid nozzle 103 is configured to melt (or dissolve in the supplied processing liquid) the solidified film on the first substrate region 21 before the solidified film on the second substrate region 22. Specifically, after the solidified film is formed on the substrate 2, the processing liquid nozzle moving device 108, under the control of the control unit 113, moves the processing liquid nozzle 103 to a discharge position facing the first substrate region 21 (hereinafter referred to as the first discharge position). The processing liquid nozzle 103 discharges the processing liquid supplied from the processing liquid supply unit 105 from the first discharge position onto the first substrate region 21, thereby melting the solidified film on the first substrate region 21. By melting the solidified film on the first substrate region 21 while rotating the stage 101, the melted solidified film and processing liquid are swept out of the substrate 2 together with foreign matter and charges on the surface of the light-shielding film 203. This makes it possible to remove foreign matter from the first substrate region 21 and to neutralize the light-shielding film 203. The substrate support pins 102 being conductive can more effectively neutralize the light-shielding film 203. As will be described in more detail below, neutralizing the light-shielding film 203 can reduce the potential difference between the light-shielding film 203 in the first substrate region 21 and the half-tone film 202 in the second substrate region 22 that occurs during the formation of the solidified film. Reducing the potential difference can reduce the occurrence of white haze-like defects caused by partial oxidation of the outermost surface of the half-tone film 202. The white haze-like defects are caused by a different amount of reflected light compared to other parts of the outermost surface of the half-tone film 202, for example, a reduced amount of reflected light.

[0020] After the solidified film on the first substrate region 21 has melted, the processing liquid nozzle moving device 108, under the control of the control unit 113, moves the processing liquid nozzle 103 again to the second discharge position. The processing liquid nozzle 103 discharges the processing liquid supplied from the processing liquid supply unit 105 from the second discharge position onto the second substrate region 22, thereby melting the solidified film on the second substrate region 22. By melting the solidified film on the second substrate region 22 while rotating the stage 101, foreign matter that has floated up from the substrate due to the solidified film is swept out of the substrate 2 together with the molten liquid resulting from the melting of the solidified film and the supplied processing liquid. This makes it possible to remove foreign matter from the second substrate region 22.

[0021] The layout information acquisition unit 111 acquires layout information of the substrate 2. For example, the layout information acquisition unit 111 acquires layout information input by a user's input operation via an input interface. The control unit 113 controls the supply of cleaning liquid by the processing liquid nozzle 103 based on the layout information acquired by the layout information acquisition unit 111. Specifically, the control unit 113 acquires the position (i.e., coordinates) of the first substrate region 21 based on the layout information. When melting the solidified film on the first substrate region 21, the control unit 113 controls the processing liquid nozzle moving device 108 to move the processing liquid nozzle 103 to a first discharge position facing the first substrate region 21 based on the acquired position of the first substrate region 21. By using the layout information, the solidified film on the first substrate region 21 can be melted simply and appropriately. The layout information acquisition unit 111 and the control unit 113 can be configured, for example, by a processor that executes a program stored in a memory.

[0022] Next, an operation example of the substrate processing apparatus 1 will be described as an example of the substrate processing method of the first embodiment with reference to FIGS. 4 to 8. Here, FIG. 4 is a flowchart showing an operation example of the substrate processing apparatus 1 according to the first embodiment. FIG. 5 is a timing chart showing an operation example of the substrate processing apparatus 1 according to the first embodiment. FIG. 6 is a cross-sectional view showing an operation example of the substrate processing apparatus 1 according to the first embodiment. FIG. 7 is a plan view showing an operation example of the substrate processing apparatus 1 according to the first embodiment. FIG. 8 is a cross-sectional view showing an operation example of the substrate processing apparatus 1 according to the first embodiment, following FIG. 6.

[0023] First, as shown in FIG. 4, the substrate processing apparatus 1 performs a pre-cooling step of forming a liquid film of a processing liquid on the substrate 2 (step S1). As shown in FIG. 5, in the pre-cooling step, the control unit 113 controls the processing liquid supply unit 105 to supply the processing liquid (ON), and causes the processing liquid supplied by the processing liquid supply unit 105 to be discharged onto the substrate 2 from the processing liquid nozzle 103 disposed at the second discharge position. At this time, the control unit 113 controls the rotation drive unit 109 to rotate the stage 101. Also, as shown in FIG. 5, in the pre-cooling step, the control unit 113 controls the cooling gas supply unit 107 to supply the cooling gas (ON), and causes the cooling gas supplied by the cooling gas supply unit 107 to be discharged from the cooling gas nozzle 1041 onto the rear surface of the substrate 2. As a result, a liquid film of the processing liquid is formed on the substrate 2, and the formed liquid film is cooled.

[0024] After the preliminary cooling step, the substrate processing apparatus 1 performs a freezing step (step S2) to solidify the liquid film of the processing liquid, as shown in Fig. 4. In the freezing step, the control unit 113 controls the processing liquid supply unit 105 to stop (OFF) the supply of the processing liquid. Also, in the freezing step, as shown in Fig. 5, the control unit 113 controls the cooling gas supply unit 107 to continue (ON) the supply of the cooling gas. By performing the freezing step, a solidified film 204 (i.e., an ice film) formed by solidifying the liquid film of the processing liquid is formed on the substrate 2, as shown in Fig. 6.

[0025] After the freezing step, the substrate processing apparatus 1 performs a substrate charge neutralization step (step S3) to neutralize the light-shielding film 203 of the substrate 2, as shown in FIG. 4. As shown in FIG. 7, in the substrate charge neutralization step, the control unit 113 controls the processing liquid nozzle moving device 108 to move the processing liquid nozzle 103 to a first discharge position on the rotational orbit of the first substrate region 21, as indicated by arrow B in FIG. 7. Then, as shown in FIG. 5, the control unit 113 controls the processing liquid supply unit 105 to supply the processing liquid (ON), and controls the processing liquid supplied by the processing liquid supply unit 105 to be discharged from the processing liquid nozzle 103, which is positioned at the first discharge position, onto the solidified film 204 on the first substrate region 21. At this time, the control unit 113 controls the rotation drive unit 109 to rotate the stage 101, as indicated by arrow A in FIG. 8. Furthermore, as shown in FIG. 5, the control unit 113 controls the cooling gas supply unit 107 to stop supplying the cooling gas (OFF). By carrying out the substrate static elimination step, as shown in Fig. 8, the solidified film 204 on the first substrate region 21 melts to form a molten liquid 205 while the solidified film 204 on the second substrate region 22 remains solidified. The mixed liquid containing the molten liquid 205 and the supplied processing liquid contains the charge that has been applied to the light-shielding film 203 as well as foreign matter in the first substrate region 21. The mixed liquid containing the foreign matter and charge is swept out of the substrate 2 by the rotational force generated by the rotation of the stage 101. This makes it possible to remove the foreign matter in the first substrate region 21 and neutralize the charge on the light-shielding film 203.

[0026] After the substrate static electricity removal process is performed, the substrate processing apparatus 1 performs a thawing process (step S5) to thaw the solidified film 204 on the second substrate region 22, as shown in FIG. 4. In the thawing process, the control unit 113 controls the processing liquid nozzle moving device 108 to move the processing liquid nozzle 103 to a second discharge position facing the rotation center of the substrate 2. Then, as shown in FIG. 5, the control unit 113 controls the processing liquid supply unit 105 to supply the processing liquid (ON), and causes the processing liquid supplied by the processing liquid supply unit 105 to be discharged from the processing liquid nozzle 103 arranged at the second discharge position onto the solidified film 204 on the second substrate region 22. At this time, the control unit 113 controls the rotation drive unit 109 to rotate the stage 101. Furthermore, as shown in FIG. 5, the control unit 113 controls the cooling gas supply unit 107 to continue stopping the supply of cooling gas (OFF). The supply time of the processing liquid in the thawing process is, for example, longer than the supply time of the processing liquid in the substrate static electricity removal process. By carrying out the thawing step, the solidified film 204 on the second substrate region 22 melts and becomes a molten liquid. The mixed liquid containing the molten liquid and the supplied processing liquid contains foreign matter in the second substrate region 22. The mixed liquid containing the foreign matter is swept out of the substrate 2 by the rotational force generated by the rotation of the stage 101. This makes it possible to remove the foreign matter in the second substrate region 22.

[0027] After the thawing step, the substrate processing apparatus 1 performs a drying step (step S5) to dry the substrate 2, as shown in Fig. 4. As shown in Fig. 5, in the drying step, the control unit 113 controls the processing liquid supply unit 105 to stop (OFF) the supply of the processing liquid, and controls the cooling gas supply unit 107 to continue stopping (OFF) the supply of the cooling gas. In addition, in the drying step, the control unit 113 controls the rotation drive unit 109 to rotate the stage 101 at a higher speed than in other steps. By rotating the stage 101 at a higher speed, the substrate 2 can be dried quickly.

[0028] During the freezing process, the liquid film of the processing liquid formed on the substrate 2 is transformed into a solidified film 204 (ice film) from the center of the substrate 2 toward the periphery by the discharge of cooling gas from a cooling gas nozzle 1041 disposed below the center of the substrate 2. Generally, when a liquid freezes, an electrification phenomenon occurs due to the difference in mobility between positive and negative ions. In the case of water, freezing is completed when the water molecules are polarized, resulting in a positive charge on the outside and a negative charge on the inside. As the formation of the solidified film 204 progresses from the center toward the periphery of the substrate 2, electrons move partially, creating a potential difference between the halftone film 202 at the center and the light-shielding film 203 at the periphery. Then, with this potential difference in place, the formation of the solidified film 204 is completed. If the solidified film 204 on the first substrate region 21 (i.e., on the light-shielding film 203) and the solidified film 204 on the second substrate region 22 (i.e., on the half-tone film 202) are melted simultaneously, there is a risk that the half-tone film 202 will be partially oxidized due to the potential difference between the light-shielding film 203 and the half-tone film 202. Abnormal oxidation of the half-tone film 202 will result in the generation of white mist-like defects.

[0029] In contrast to this, according to the first embodiment, as described above, the solidified film 204 on the first substrate region 21 is melted before the solidified film 204 on the second substrate region 22. This makes it possible to melt the solidified film 204 on the second substrate region 22 after the light-shielding film 203 located on the first substrate region 21 is neutralized to reduce the potential difference, thereby reducing defects due to partial oxidation of the half-tone film 202 located on the second substrate region 22.

[0030] Furthermore, according to the first embodiment, based on the position of the first substrate region 21 acquired in advance based on the layout information, a processing liquid having a temperature equal to or higher than the melting point of the solidified film 204 on the first substrate region 21 can be supplied to the solidified film 204 on the first substrate region 21. This makes it possible to simply and reliably reduce defects in the halftone film 202 due to partial oxidation.

[0031] Although the above has described an example in which the light-shielding film 203 arranged on the outer periphery of the substrate 2 can be effectively neutralized, the first embodiment may also be applied to neutralize a light-shielding film arranged on the central side of the substrate 2. Furthermore, instead of providing the processing liquid nozzle moving device 108 that moves the processing liquid nozzle 103, a nozzle that discharges the processing liquid at the first discharge position and a nozzle that discharges the processing liquid at the second discharge position may be separately provided.

[0032] (First Modification of the First Embodiment) Next, a first modified example of the first embodiment in which cooling of the substrate 2 is continued in the substrate static neutralization step will be described, focusing on the differences from the above-described example. Fig. 9 is a cross-sectional view showing an example of operation of the substrate processing apparatus 1 according to the first modified example of the first embodiment.

[0033] 5 and 8 have described an example in which the supply of cooling gas to the substrate 2 is stopped in the substrate static electricity removing process. In contrast to this, as shown in Fig. 9, the substrate processing apparatus 1 may continue to supply cooling gas to the substrate 2 by the cooling gas nozzle 1041 in the substrate static electricity removing process.

[0034] According to the first variant of the first embodiment, melting of the solidified film 204 on the second substrate region 22 can be prevented during the substrate de-electrification process, thereby more effectively reducing defects caused by partial oxidation of the halftone film 202.

[0035] (Second Modification of the First Embodiment) Next, a second modification of the first embodiment in which the solidified film 204 on the first substrate region 21 is melted by heated gas will be described, focusing on the differences from the above-described example.

[0036] 10 is a diagram showing a substrate processing apparatus 1 according to a second modified example of the first embodiment. The substrate processing apparatus 1 according to the second modified example of the first embodiment further includes a heating gas nozzle 123 and a heating gas supply unit 125 in addition to the configuration shown in FIG.

[0037] The heating gas nozzle 123 is configured to supply a heating gas having a temperature equal to or higher than the melting point of the solidified film 204 to the solidified film 204 on the first substrate region 21. The heating gas is, for example, nitrogen gas. FIG. 11 is a plan view showing a portion of the substrate processing apparatus 1 according to a second modified example of the first embodiment. As shown in FIG. 11, the heating gas nozzle 123 is arranged on a rotational path B of the first substrate region 21 of the substrate 2. The heating gas nozzle 123 may be moved onto the rotational path B by a moving device (not shown). The heating gas nozzle 123 is connected to a heating gas supply unit 125. The heating gas supply unit 125 supplies a heating gas to the heating gas nozzle 123. The heating gas supply unit 125 includes, for example, a storage tank for storing liquefied heating gas and a valve for adjusting the flow rate of the heating gas supplied from the storage tank to the heating gas nozzle 123. The control unit 113 controls the flow rate of the heating gas supplied by the heating gas supply unit 125. The heating gas nozzle 123 discharges the heating gas supplied from the heating gas supply unit 125 onto the solidified film 204 on the first substrate region 21, thereby melting the solidified film 204 on the first substrate region 21.

[0038] FIG. 12 is a timing chart showing the operation of the substrate processing apparatus 1 according to the second modified example of the first embodiment. FIG. 13 is a cross-sectional view showing an example of the operation of the substrate processing apparatus according to the second modified example of the first embodiment. As shown in FIG. 12, in the second modified example of the first embodiment, the control unit 113 controls the processing liquid supply unit 105 to supply the processing liquid (ON) and the heating gas supply unit 125 to supply the heating gas (ON) in the substrate static neutralization process. As a result, as shown in FIG. 13, the processing liquid supplied by the processing liquid supply unit 105 is discharged from the processing liquid nozzle 103 onto the solidified film 204 on the first substrate region 21, and the heating gas supplied by the heating gas supply unit 125 is discharged from the heating gas nozzle 123 onto the solidified film 204 on the first substrate region 21. Note that in FIG. 12, the supply of the cooling gas is stopped (OFF) in the substrate static neutralization process. The supply of the cooling gas is not limited to being stopped in the substrate static neutralization process; as shown in FIG. 13, the supply of the cooling gas may be continued in the substrate static neutralization process.

[0039] According to the second modification of the first embodiment, the melting of the solidified film 204 on the first substrate region 21 can be promoted by the heated gas, and the processing time for the substrate 2 can be shortened compared to when the solidified film 204 on the first substrate region 21 is melted by supplying a processing liquid. Note that the melting of the solidified film 204 on the first substrate region 21 may be achieved by supplying only the heated gas. Furthermore, if the heated gas nozzle 123 is configured to be movable to a position facing the solidified film 204 on the second substrate region 22, the heated gas can also be used to melt the solidified film 204 on the second substrate region 22.

[0040] (Second embodiment) Next, a second embodiment in which a ground wire is used to neutralize the substrate 2 will be described, focusing on the differences from the second modified example of the first embodiment. Fig. 14 is a diagram showing an example of a substrate processing apparatus 1 according to the second embodiment.

[0041] 14, the substrate processing apparatus 1 according to the second embodiment further includes a ground wire 127 and a heating gas nozzle moving device 129 in addition to the configuration of FIG. 10. The ground wire 127 is provided on the heating gas nozzle 123. The ground wire 127 is connected to a ground potential. The heating gas nozzle moving device 129 moves the ground wire 127 together with the heating gas nozzle 123 under the control of the control unit 113. The specific configuration of the heating gas nozzle moving device 129 may be similar to that of the processing liquid nozzle moving device 108.

[0042] FIG. 15 is a timing chart showing an example of operation of the substrate processing apparatus 1 according to the second embodiment. FIG. 16 is a diagram showing an example of operation of the substrate processing apparatus 1 according to the second embodiment. As shown in FIG. 15 , in the second embodiment, the substrate processing apparatus 1 performs contact static elimination in a substrate static elimination step by bringing the ground wire 127 into contact with the light-shielding film 203 to eliminate static electricity from the light-shielding film 203. More specifically, in the substrate static elimination step, the control unit 113 controls the heating gas nozzle moving device 129 to move the heating gas nozzle 123 to a position facing the solidified film 204 on the first substrate region 21. Then, the control unit 113 controls the heating gas supply unit 125 to execute (ON) the supply of heating gas. As a result, the heating gas supplied by the heating gas supply unit 125 is discharged from the heating gas nozzle 123 onto the solidified film 204 on the first substrate region 21. As the melting of the solidified film 204 on the first substrate region 21 by the heating gas progresses, the heating gas nozzle moving device 129 gradually lowers the heating gas nozzle 123. The speed at which the heating gas nozzle 123 is lowered may be a speed that is preset depending on the melting speed of the solidified film 204. Then, as shown in FIG. 16 , when the grounding wire 127 provided on the heating gas nozzle 123 has moved by an amount that makes contact with the surface of the substrate 2 in the first substrate region 21 (i.e., the light-shielding film 203), the heating gas nozzle moving device 129 stops the lowering of the heating gas nozzle 123. When the grounding wire 127 comes into contact with the light-shielding film 203, the electric charge stored on the light-shielding film 203 flows to the ground potential via the grounding wire 127. This neutralizes the light-shielding film 203.

[0043] If the ground wire 127 is brought into contact with the light-shielding film 203 while the stage 101 is being rotated, there is a risk that the light-shielding film 203 may be scratched by the ground wire 127. To prevent the light-shielding film 203 from being scratched, the control unit 113 stops the rotation of the stage 101 when the ground wire 127 is in contact with the light-shielding film 203.

[0044] According to the second embodiment, the use of the ground line 127 makes it possible to quickly remove electricity from the light-shielding film 203. This makes it possible to shorten the processing time for the substrate 2.

[0045] (First modified example of the second embodiment) Next, a first modified example of the second embodiment in which the substrate 2 is neutralized by an ionizer will be described, focusing on the differences from the configuration in Fig. 14. Fig. 17 is a diagram showing a substrate processing apparatus 1 according to the first modified example of the second embodiment.

[0046] 17, the substrate processing apparatus 1 according to the first modified example of the second embodiment differs from that of FIG. 14 in that it includes an ionizer 131 instead of the ground wire 127. The ionizer 131 is a device that generates ions within an irradiation range by irradiating, for example, soft X-rays having an ionizing effect, and removes static electricity from the substrate 2 using the generated ions. The control unit 113 controls the driving of the ionizer 131.

[0047] 18 is a timing chart showing the operation of the substrate processing apparatus 1 according to the first modified example of the second embodiment. As shown in FIG. 18, in the first modified example of the second embodiment, the control unit 113 drives (turns on) the ionizer 131 in all steps, including the pre-cooling step, the freezing step, the substrate static neutralization step, the thawing step, and the drying step. As a result, in the substrate static neutralization step, the light-shielding film 203 exposed by the melting of the solidified film 204 on the first substrate region 21 by the heated gas can be neutralized by the ions generated by the ionizer 131. Furthermore, the electric charge on the substrate 2 can be neutralized in steps other than the substrate static neutralization step.

[0048] According to the first modification of the second embodiment, the ionizer 131 is used to neutralize the charge on the light-shielding film 203 in a non-contact manner.

[0049] (Second Modification of the Second Embodiment) Next, a first modified example of the second embodiment will be described, in which the substrate 2 is neutralized by both the ground wire 127 and the ionizer 131. FIG. 19 is a diagram showing a substrate processing apparatus 1 according to the second modified example of the second embodiment. As shown in FIG. 19, the substrate processing apparatus 1 according to the second modified example of the second embodiment further includes a ground wire 127 in addition to the configuration shown in FIG. 17, and neutralizes the light-shielding film 203 by using both the ground wire 127 and the ionizer 131. The neutralization operation of the light-shielding film 203 using the ground wire 127 is the same as the example shown in FIG. 16.

[0050] FIG. 20 is a timing chart showing the operation of the substrate processing apparatus 1 according to the second modified example of the second embodiment. FIG. 18 illustrates an example in which the ionizer 131 is driven in all processes. In contrast, as shown in FIG. 20, in the second modified example of the second embodiment, in addition to driving the ionizer 131, the light-shielding film 203 is neutralized using the ground wire 127. Note that the timing chart for the ionizer 131 is not shown in FIG. 20. In the example shown in FIG. 20, the stage 101 is rotated in the freezing process. The duration of the substrate neutralization process shown in FIG. 20 can be shortened compared to the durations of the substrate neutralization processes shown in FIGS. 15 and 18. In the second modified example of the second embodiment, the light-shielding film 203 can be neutralized using the ground wire 127 in addition to the ionizer 131, thereby enabling the light-shielding film 203 to be neutralized quickly and appropriately.

[0051] (Third modified example of the second embodiment) 21 is a timing chart showing the operation of the substrate processing apparatus 1 according to the third modified example of the second embodiment. As shown in FIG. 21, in contrast to FIG. 20, the stage 101 may be stopped during the freezing step. By stopping the stage 101 during the freezing step, it is possible to reduce the movement of charges when the solidified film 204 is formed. This makes it possible to reduce the charging of the light-shielding film 203, which may cause defects.

[0052] (Fourth Modification of the Second Embodiment) Next, a fourth modification of the second embodiment in which the ground wire 127 rotates together with the stage 101 will be described, focusing on the differences from the configuration in FIG.

[0053] FIG. 22 is a diagram showing a substrate processing apparatus 1 according to a fourth modified example of the second embodiment. As shown in FIG. 22, the substrate processing apparatus 1 according to the fourth modified example of the second embodiment differs from the configuration shown in FIG. 19 in that a ground wire 127 is provided on the stage 101. In the example shown in FIG. 22, the ground wire 127 is provided outside the substrate support pins 102. The ground wire 127 is rotatable together with the stage 101. To reduce deterioration of the ground wire 127 due to the processing liquid, the ground wire 127 may be partially protected by a waterproof cover 133. The ground wire 127 may be configured to be in constant contact with the outermost surface of the substrate 2. Alternatively, the ground wire 127 may be configured to be retracted from the outermost surface of the substrate 2 by a moving device (not shown) until the light-shielding film 203 is exposed.

[0054] Fig. 23 is a timing chart showing the operation of the substrate processing apparatus 1 according to the fourth modified example of the second embodiment. As shown in Fig. 23, in the fourth modified example of the second embodiment, the control unit 113 rotates the stage 101 in the substrate static neutralization step. The ground wire 127 rotates together with the stage 101 and the substrate 2 on the stage 101, and therefore, the ground wire 127 can prevent the light-shielding film 203 of the substrate 2 from being scratched. In the example shown in Fig. 23, the control unit 113 also rotates the stage 101 in the freezing step.

[0055] According to the fourth modification of the second embodiment, similarly to the configuration of FIG. 19, the light-shielding film 203 can be efficiently neutralized by both the ground wire 127 and the ionizer 131.

[0056] (Fifth Modification of the Second Embodiment) Fig. 24 is a timing chart showing the operation of the substrate processing apparatus 1 according to the fifth modified example of the second embodiment. As shown in Fig. 24, unlike Fig. 23, the rotation of the stage 101 may be stopped during the freezing step. By stopping the stage 101 during the freezing step, it is possible to reduce charging of the light-shielding film 203, which may cause defects.

[0057] (Third embodiment) Next, a third embodiment in which the solidified film 204 is melted by light irradiation will be described, focusing on the differences from the first and second embodiments. Fig. 25 is a diagram showing an example of a substrate processing apparatus 1 according to the third embodiment. Fig. 26 is a plan view showing a part of the substrate processing apparatus 1 according to the third embodiment.

[0058] As shown in FIGS. 25 and 26, the substrate processing apparatus 1 according to the third embodiment includes a lamp 135. The lamp 135 is, for example, a halogen lamp. The lamp 135 irradiates the first substrate region 21 with light having a wavelength that is absorbed by the light-shielding film 203, thereby melting the solidified film 204 on the first substrate region 21. The lamp 135 irradiates light having a wavelength in the range of approximately 700 to 2000 nm, for example. The light irradiated from the lamp 135 may be infrared light. In the example shown in FIGS. 25 and 26, the lamp 135 is formed in a rod shape over a length that straddles (i.e., crosses) the substrate 2 along the X-axis direction.

[0059] The control unit 113 controls the light irradiation by the lamp 135. For example, the control unit 113 may cause the lamp 135 to irradiate pulsed light having a wavelength in the range of approximately 700 to 2000 nm multiple times at predetermined time intervals.

[0060] The light irradiated by the lamp 135 is absorbed by the light-shielding film 203 arranged in the first substrate region 21 and heats the light-shielding film 203. As the light-shielding film 203 is heated, the solidified film 204 on the first substrate region 21 in contact with the light-shielding film 203 melts. On the other hand, the light irradiated by the lamp 135 is hardly absorbed by the half-tone film 202 arranged in the second substrate region 22 and hardly heats the half-tone film 202. As the half-tone film 202 is hardly heated, the solidified film 204 on the second substrate region 22 in contact with the half-tone film 202 hardly melts. Note that the solidified film 204 on the second substrate region 22 is melted by the processing liquid discharged from the processing liquid nozzle 103 after the substrate static elimination process using the ionizer 131 is completed. When the solidified film 204 on the first substrate region 21 is melted using the lamp 135, the processing liquid supply nozzle 103 may be retracted to the retracted position by the processing liquid nozzle moving device 108 described above.

[0061] As in the first and second embodiments, in the third embodiment, the solidified film 204 on the first substrate region 21 can be melted before the solidified film 204 on the second substrate region 22. This makes it possible to reduce the occurrence of defects due to partial oxidation of the halftone film 202 located in the second substrate region 22.

[0062] (First modified example of the third embodiment) Next, a first modified example of the third embodiment that prevents light absorption in the substrate 2 other than the light-shielding film 203 will be described, focusing on the differences from the configuration in Fig. 25. Fig. 27 is a diagram showing a substrate processing apparatus 1 according to the first modified example of the third embodiment.

[0063] As shown in Fig. 27, the substrate processing apparatus 1 according to the first modified example of the third embodiment further includes a filter 137 in addition to the configuration of Fig. 25. In the example shown in Fig. 27, the filter 137 has a plate shape. The filter 137 is disposed between the lamp 135 and the substrate 2. The lamp 135 irradiates the substrate 2 with light having a range of wavelengths.

[0064] The filter 137 is made of a material that absorbs light of the same wavelength as at least one of the quartz substrate 201, the half-tone film 202, and the solidified film 204. For example, the filter 137 may have a laminated structure in which a layer made of the same material as the quartz substrate 201, a layer made of the same material as the half-tone film 202, and a layer made of a material that has the same absorption wavelength as or a similar absorption wavelength to the solidified film 204 are stacked.

[0065] FIG. 28 is an explanatory diagram illustrating the operation of the substrate processing apparatus 1 according to the first modified example of the third embodiment. As shown in FIG. 28, in the first modified example of the third embodiment, among the light irradiated from the lamp 135, light L2 having a high absorption rate by the quartz substrate 201, light L3 having a high absorption rate by the half-tone film 202, and light L4 having a high absorption rate by the solidified film 204 are absorbed by the filter 137. That is, the amount of light L2 to L4 transmitted through the filter 137 is reduced, thereby reducing the amount of light irradiated onto the substrate 2. On the other hand, light L1 having a high absorption rate by the light-shielding film 203 is hardly absorbed by the filter 137 and is transmitted through the filter 137 to be irradiated onto the substrate 2. Therefore, light L1 is absorbed by the light-shielding film 203 arranged in the first substrate region 21, and the amount of light absorbed by the half-tone film 202, the quartz substrate 201, and the solidified film 204 arranged in the second substrate region 22 is reduced.

[0066] Therefore, according to the first modified example of the third embodiment, by inhibiting light absorption in portions other than the light-shielding film 203, it is possible to more reliably melt the solidified film 204 on the first substrate region 21 before the solidified film 204 on the second substrate region 22. This makes it possible to more effectively reduce the occurrence of defects due to partial oxidation of the half-tone film 202 located in the second substrate region 22.

[0067] (Second modified example of the third embodiment) Fig. 29 is a plan view of a portion of a substrate processing apparatus 1 according to a second modified example of the third embodiment. Fig. 26 describes an example in which the lamps 135 are formed to a length that spans the substrate 2. In contrast, as shown in Fig. 29, the lamps 135 may be formed so as to cover a portion of the first substrate region 21 of the substrate 2. That is, the lamps 135 may be disposed on the rotational orbit of the first substrate region 21. According to the second modified example of the third embodiment, the lamps 135 can be made smaller and costs can be reduced.

[0068] (Third Modification of the Third Embodiment) FIG. 30 is a block diagram showing a substrate processing apparatus 1 according to a third modified example of the third embodiment. Up to now, an example has been described in which each freeze cleaning step is performed in a single chamber. However, as shown in FIG. 30, each freeze cleaning step may be performed separately in multiple chambers. In the example shown in FIG. 30, the substrate processing apparatus 1 includes a hydrophilization unit 1001, a freeze rinse drying unit 1002, and an infrared unit 1003. Note that a substrate transport mechanism (not shown) is provided between the hydrophilization unit 1001, the freeze rinse drying unit 1002, and the infrared unit 1003 to transfer substrates 2 between each unit.

[0069] The hydrophilization unit 1001 irradiates the surface of the substrate 2 with ultraviolet light before the above-mentioned preliminary cooling step, thereby improving the wettability of the substrate 2 with the processing liquid.

[0070] The freeze rinse dry unit 1002 performs a pre-cooling step, a freezing step, a thawing step (rinsing step), and a drying step.

[0071] The infrared unit 1003 performs the substrate static elimination step described above. That is, the substrate 2 on which the liquid film has been frozen in the freezing step is transported to the infrared unit 1003 while still frozen. Then, the substrate 2, on which the solidified film 204 on the first substrate region 21 has been thawed (partially thawed) in the infrared unit 1003 and neutralized, is transported to the freeze rinse dry unit 1002 for the thawing step. Note that the melting of the solidified film 204 on the first substrate region 21 in the substrate static elimination step is performed by infrared irradiation.

[0072] According to the third modification of the third embodiment, each freeze cleaning step is performed in a plurality of chambers, thereby improving the degree of freedom in designing each step.

[0073] (Fourth Modification of the Third Embodiment) 31 is a diagram showing a substrate processing apparatus 1 according to a fourth modified example of the third embodiment. Up to now, an example has been described in which the solidified film 204 on the first substrate region 21 is melted by irradiating the substrate 2 with infrared rays from a lamp 135 arranged above the substrate 2. In contrast to this, as shown in FIG. 31, in the infrared unit 1003, the lamp 135 may be arranged below the substrate 2.

[0074] It should be noted that this embodiment is not limited to the neutralization of the substrate 2 described above, but may also be used to neutralize a metal film on a substrate having a conductive frame-shaped metal film on an insulating material such as quartz glass, and a film made of a different material from the metal film arranged in an island shape inside the metal film.

[0075] Although several embodiments have been described above, these embodiments are presented only as examples and are not intended to limit the scope of the invention. The novel apparatus and method described herein may be embodied in various other forms. Furthermore, various omissions, substitutions, and modifications may be made to the forms of the apparatus and method described herein without departing from the spirit of the invention. The appended claims and their equivalents are intended to cover such forms and modifications that fall within the scope and spirit of the invention. [Explanation of symbols]

[0076] 2: substrate, 21: first substrate area, 22: second substrate area, 202: halftone film, 203: light-shielding film, 204: solidified film

Claims

1. forming a liquid film on a substrate having a first region on the outermost surface of which a first film is provided and a second region on the outermost surface of which a second film made of a material different from that of the first film is provided; solidifying the liquid film to form a solidified film; a substrate processing method including melting the solidified film on the first region prior to melting the solidified film on the second region.

2. The substrate processing method according to claim 1 , wherein the first region is located on the outer periphery of the second region.

3. 2. The substrate processing method of claim 1, wherein melting the solidified film on the first region includes supplying at least one of a gas and a liquid having a temperature equal to or higher than a melting point of the solidified film on the first region to the solidified film on the first region.

4. 4. The substrate processing method according to claim 3, wherein the supply of at least one of the gas and the liquid to the solidified film on the first region is performed based on a position of the first region that is acquired in advance.

5. 2. The substrate processing method according to claim 1, wherein melting the solidified film on the first region comprises irradiating the first region with light of a wavelength that is absorbed by the first film.

6. 6. The substrate processing method according to claim 5, wherein the light having a wavelength absorbed by the first film is infrared light.

7. 6. The substrate processing method according to claim 5, wherein the first film has a higher absorptance of light having a wavelength absorbed by the first film than the second film.

8. 6. The substrate processing method according to claim 5, wherein the first film has a higher absorptance of light having a wavelength absorbed by the first film than the solidified film.

9. 6. The substrate processing method of claim 5, wherein the irradiation of light having a wavelength absorbed by the first film is performed in a state where a filter containing the same material as at least one of the second film and the solidified film is placed between a light source of light having a wavelength absorbed by the first film and the substrate.

10. The substrate processing method according to claim 1 , further comprising: using an ionizer to remove electricity from the first film exposed by melting the solidified film on the first region.

11. The substrate processing method according to claim 1 , further comprising: using a ground wire to remove electricity from the first film exposed by melting the solidified film on the first region.

12. The substrate treatment method according to claim 11 , wherein the neutralization of the first film includes contacting the ground wire with the first film based on a position of the first region acquired in advance.

13. a holder for holding a substrate having a first region on the outermost surface of which a first film is provided, and a second region on the outermost surface of which a second film made of a material different from that of the first film is provided; a liquid film forming unit that forms a liquid film on the substrate; a solidified film forming unit that solidifies the liquid film to form a solidified film; a melting section that melts the solidified film on the first region before the solidified film on the second region; A substrate processing apparatus comprising:

14. the melting section has a nozzle for supplying at least one of a gas and a liquid having a temperature equal to or higher than the melting point of the solidified film on the first region to the solidified film on the first region, The substrate processing apparatus includes: a layout information acquisition unit that acquires layout information of the board; a control unit that controls the supply of at least one of the gas and the liquid by the nozzle based on the acquired layout information; The substrate processing apparatus of claim 13 further comprising:

15. The substrate processing apparatus according to claim 14 , further comprising: a charge eliminating unit that eliminates charge from the first film by contacting the first film that is exposed by melting the solidified film on the first region.

16. The substrate processing apparatus according to claim 13 , wherein the melting unit has an irradiation unit that irradiates the first region with light having a wavelength that is absorbed by the first film.

Images