JP2019046928A - Substrate processing method and substrate processing apparatus - Google Patents

Abstract

To prevent exposure of an upper surface of a substrate before forming a coating film and form the coating film on the substrate suitably.SOLUTION: A substrate processing apparatus comprises: a rinse solution supply part for supplying a rinse solution to an upper surface 91 of a substrate 9; a displacing solution supply part 7 for supplying a displacing solution to the upper surface 91 of the substrate 9 to replace the rinse solution on the upper surface 91 of the substrate 9 with the displacing solution and form on the upper surface 91, a displacing solution film as a liquid film of the displacing solution; and a coating solution supply part for supplying a coating solution which is a water-soluble polymer solution to a surface of the displacing solution film to form a coating film as a film of the coating solution on the upper surface 91 of the substrate 9. The displacing solution supply part 7 includes: a blending part 71 which blends a water-soluble organic solvent with an aqueous solvent to create a displacing solution having smaller surface tension than the rinse solution; and a second nozzle 52 which discharges toward the substrate 9, the displacing solution delivered from the blending part 71. This makes it possible to prevent the upper surface 91 of the substrate 9 from being exposed before forming the coating film; and makes it possible to form the coating film suitably.SELECTED DRAWING: Figure 1

Description

  The present invention relates to technology for processing a substrate.

  Conventionally, in the process of manufacturing a semiconductor substrate (hereinafter simply referred to as a “substrate”), various treatments are performed on the substrate. For example, etching or the like on the surface of a substrate by discharging a chemical solution from a nozzle onto a substrate on which a pattern of resist (that is, a structure which is a collection of a large number of fine structural elements) is formed on the surface Chemical treatment is performed.

  Further, after the chemical treatment on the substrate, a rinse treatment for removing pure water by supplying pure water to the substrate and a drying treatment for removing the liquid on the substrate by rotating the substrate at high speed are further performed. When a large number of fine pattern elements are formed on the substrate, when the rinse process and the drying process are sequentially performed, a liquid surface of pure water is formed between two adjacent pattern elements in the process of drying. In this case, there is a possibility that the pattern element may collapse due to the surface tension of pure water acting on the pattern element.

  Therefore, Patent Document 1 proposes a method for preventing the collapse of pattern elements in the drying process by filling the filler solution between the pattern elements, solidifying the filler such as the polymer, and then performing the drying process. ing. The filler solidified on the substrate is gasified and removed, for example, by performing dry etching or the like in another device after the drying process.

  Further, in Patent Document 2, the substrate after the etching process is immersed in pure water stored in a storage tank and rinsed, and after pure water in the storage tank is replaced with IPA (isopropyl alcohol), the IPA A filler such as naphthalene is dissolved. Then, a film of the filler is formed on the substrate surface by evaporating IPA, and after performing a drying process, the naphthalene film is sublimed in the air.

JP, 2016-219471, A JP, 2008-10638, A

  By the way, if it is going to dissolve a filler in IPA with which a substrate was immersed and it is going to form a film of a filler like patent documents 2, a lot of fillers will be needed. On the other hand, in the single-wafer type substrate processing apparatus as in Patent Document 1, when the substrate surface is a hydrophobic surface due to chemical treatment or the like, the substrate surface is partially exposed when rinsing with pure water, and the pattern is An element may collapse. Therefore, it is also conceivable to coat the substrate surface with IPA generally used in a substrate processing apparatus, but in this case, when a filler such as a water-soluble polymer is dropped onto the liquid film of IPA, the filler agglomerates. Thus, it is difficult to suitably form a coating film of the filler on the substrate.

  The present invention has been made in view of the above problems, and aims to prevent the top surface of the substrate from being exposed before the formation of the coating film, and to preferably form the coating film on the substrate.

  The invention according to claim 1 is a substrate processing method for processing a substrate, comprising: a) holding the substrate in a horizontal state; b) supplying a rinse liquid to the upper surface of the substrate; c) water-soluble Organic solvent and an aqueous solvent to form a substitution solution having a smaller surface tension than the rinse solution, and d) after the steps b) and c), on the upper surface of the substrate. Replacing the rinse solution on the upper surface of the substrate with the replacement fluid by supplying the replacement fluid to form a replacement fluid film, which is a liquid film of the replacement fluid, on the upper surface; and d) supplying a coating solution, which is a water-soluble polymer solution, onto the substitution film, and forming a coating film, which is a film of the coating solution, on the upper surface of the substrate after the step d).

  The invention according to claim 2 is the substrate processing method according to claim 1, wherein, in the step d), the substrate is rotated about a central axis directed in the vertical direction.

  The invention according to claim 3 is the substrate processing method according to claim 1 or 2, wherein in the step c), the proportion of the water-soluble organic solvent to be mixed with the aqueous solvent can be adjusted.

  The invention according to a fourth aspect is the substrate processing method according to the third aspect, wherein, in the step c), the water solution mixed with the aqueous solvent based on input information on the formation processing of the coating film. The proportion of the organic solvent is adjusted.

  The invention according to claim 5 is the substrate processing method according to any one of claims 1 to 4, wherein the volume concentration of the water-soluble organic solvent in the substitution liquid is 15% or more and 30% or less. It is.

  The invention according to claim 6 is the substrate processing method according to any one of claims 1 to 5, wherein the water-soluble organic solvent is isopropyl alcohol.

  The invention according to claim 7 is the substrate processing method according to any one of claims 1 to 6, wherein the rinse liquid is a liquid of the same type as the aqueous solvent of the replacement liquid.

  The invention according to claim 8 is the substrate processing method according to any one of claims 1 to 7, wherein a structure is previously formed on the upper surface of the substrate, and in the step e), The gaps in the structure are filled with the coating solution.

  The invention according to claim 9 is the substrate processing method according to any one of claims 1 to 8, wherein the upper surface of the substrate just before the supply of the substitution liquid is started in the step d). Is the hydrophobic surface.

  The invention according to claim 10 is a substrate processing apparatus for processing a substrate, wherein the substrate holding unit holds the substrate in a horizontal state, a rinse liquid supply unit for supplying a rinse liquid to the upper surface of the substrate, and the substrate A replacement liquid is provided on the upper surface of the substrate to replace the rinse liquid on the upper surface of the substrate with the replacement liquid to form a replacement liquid film which is a liquid film of the replacement liquid on the upper surface A supply unit; and a coating solution supply unit for supplying a coating solution, which is a water-soluble polymer solution, onto the substitution solution film, and forming a coating film, which is a film of the coating solution, on the upper surface of the substrate. The substitution solution supply unit mixes a water-soluble organic solvent and an aqueous solvent, and generates a substitution solution having a smaller surface tension than the rinse solution; and the substitution solution delivered from the mixing unit. And a replacement liquid discharger for discharging toward the substrate.

  The invention according to claim 11 is the substrate processing apparatus according to claim 10, further comprising: a substrate rotating mechanism configured to rotate the substrate with the substrate holding unit around a central axis facing in the up and down direction; When the liquid film is formed, the substrate is rotated by the substrate rotation mechanism.

  The invention according to claim 12 is the substrate processing apparatus according to claim 10 or 11, wherein the substitution liquid supply unit is configured to use the proportion of the water-soluble organic solvent to be mixed with the aqueous solvent in the mixing unit. It further comprises a mixing ratio adjusting unit to adjust.

  The invention according to claim 13 is the substrate processing apparatus according to claim 12, wherein the substitution liquid supply unit controls the mixing ratio adjusting unit on the basis of input information on a forming process of the coating film. The control unit is further provided.

  The invention according to claim 14 is the substrate processing apparatus according to any one of claims 10 to 13, wherein the volume concentration of the water-soluble organic solvent in the replacement liquid is 15% or more and 30% or less. It is.

  The invention according to claim 15 is the substrate processing apparatus according to any one of claims 10 to 14, wherein the water-soluble organic solvent is isopropyl alcohol.

  The invention according to claim 16 is the substrate processing apparatus according to any one of claims 10 to 15, wherein the rinse liquid is a liquid of the same type as the aqueous solvent of the replacement liquid.

  The invention according to claim 17 is the substrate processing apparatus according to any one of claims 10 to 16, wherein a structure is previously formed on the upper surface of the substrate, and the upper surface of the substrate is By forming the coating film on the substrate, the gaps in the structure are filled with the coating solution.

  The invention according to claim 18 is the substrate processing apparatus according to any one of claims 10 to 17, wherein the upper surface of the substrate immediately before the supply of the substitution liquid is started is a hydrophobic surface. .

  In the present invention, it is possible to prevent the upper surface of the substrate from being exposed before the formation of the coating film, and to form the coating film on the substrate suitably.

It is a side view of the substrate processing device concerning one embodiment. It is a side view of a substrate processing device. It is a block diagram which shows a process liquid supply part. It is a top view of a substrate. It is a figure which shows the flow of a process of a board | substrate. FIG. 5 shows the rotational speed during processing of a substrate. It is a figure which shows an experimental result. It is a figure which shows an experimental result.

  FIG. 1 is a side view showing the configuration of a substrate processing apparatus 1 according to an embodiment of the present invention. The substrate processing apparatus 1 is a sheet-fed apparatus that processes semiconductor substrates 9 (hereinafter simply referred to as "substrates 9") one by one. The substrate processing apparatus 1 supplies a processing liquid to the substrate 9 to perform processing. In FIG. 1, a part of a structure of the substrate processing apparatus 1 is shown in a cross section.

  The substrate processing apparatus 1 includes a substrate holding unit 31, a substrate rotation mechanism 33, a cover plate 35, a cup unit 4, and a processing liquid supply unit 5. The substrate holding unit 31 is a so-called vacuum chuck that holds the central portion of the lower main surface (hereinafter referred to as “lower surface 92”) of the substrate 9 by vacuum suction. The substrate holding unit 31 is provided rotatably about a central axis J1 facing in the vertical direction. The substrate 9 is disposed above the substrate holding unit 31. The substrate 9 is held by suction by the substrate holding unit 31 in a horizontal state. The substrate rotation mechanism 33 is disposed below the substrate holding unit 31. The substrate rotation mechanism 33 rotates the substrate 9 together with the substrate holding unit 31 about the central axis J1.

  The cover plate 35 is a substantially annular plate shaped member centering on the central axis J1. The cover plate 35 is located below the substrate 9 held by the substrate holding portion 31 and vertically opposed to the lower surface 92 of the substrate 9. In the example shown in FIG. 1, the outer diameter of the cover plate 35 is substantially the same as the diameter of the substrate 9. The cover plate 35 is vertically moved between a first position shown in FIG. 1 and a second position shown in FIG. 2 by an elevating mechanism (not shown). The second position is located below the first position. As shown in FIG. 2, when the cover plate 35 is in the second position, the cover plate 35 is engaged with the substrate rotation mechanism 33 and rotates together with the substrate 9 and the substrate holding unit 31. On the other hand, as shown in FIG. 1, when the cover plate 35 is in the first position, the cover plate 35 does not rotate because it is separated from the substrate rotation mechanism 33.

  The processing liquid supply unit 5 supplies a plurality of processing liquids individually to the substrate 9. The plurality of types of processing solutions include, for example, a chemical solution, a rinse solution, a replacement solution, a filler solution and a stripping solution described later. The treatment liquid supply unit 5 includes a first nozzle 51, a second nozzle 52, a third nozzle 53, and a fourth nozzle 64. Further, as shown in FIG. 3 described later, the treatment liquid supply unit 5 further includes a mixing unit 71, a mixing ratio adjustment unit 72, and a concentration control unit 73.

  The first nozzle 51, the second nozzle 52, and the third nozzle 53 respectively supply the processing liquid from above the substrate 9 toward the upper main surface of the substrate 9 (hereinafter referred to as "upper surface 91"). In the state shown in FIG. 1, the first nozzle 51 is located above the substrate, and the processing liquid is supplied from the first nozzle 51 to the substrate 9. At this time, the second nozzle 52 and the third nozzle 53 are retracted radially outward of the outer edge of the substrate 9. When the processing liquid is supplied from the second nozzle 52 to the substrate 9, the first nozzle 51 and the third nozzle 53 are retracted radially outward of the outer edge of the substrate 9, and the second nozzle 52 is the substrate 9. Located above the When the treatment liquid is supplied from the third nozzle 53 to the substrate 9, the first nozzle 51 and the second nozzle 52 are retracted radially outward of the outer edge of the substrate 9, and the third nozzle 53 is disposed on the substrate 9. Located above the

  The fourth nozzle 64 is disposed below the substrate 9. The fourth nozzle 64 supplies the processing solution toward the outer edge of the lower surface 92 of the substrate 9 from below the substrate 9. As shown in FIG. 1, the fourth nozzle 64 is inserted into the opening 351 provided on the outer peripheral portion of the cover plate 35 in a state where the cover plate 35 is positioned at the first position, and discharges the treatment liquid. On the other hand, as shown in FIG. 2, in the state where the cover plate 35 is positioned at the second position, the fourth nozzle 64 is moved downward by the nozzle moving mechanism 641 and retracted below the cover plate 35. There is. In the state where the fourth nozzle 64 is retracted below the cover plate 35, the supply of the processing liquid from the fourth nozzle 64 to the substrate 9 is not performed.

  The cup part 4 shown to FIG. 1 and FIG. 2 is an annular member centering on the central axis J1. The cup portion 4 is disposed around the substrate 9, the substrate holding portion 31 and the cover plate 35 and covers the sides and the lower side of the substrate 9, the substrate holding portion 31 and the cover plate 35. The cup portion 4 is a liquid receiving portion for receiving a processing liquid or the like scattered from the rotating substrate 9 toward the periphery. The inner side surface of the cup portion 4 is formed of, for example, a water repellent material. The cup portion 4 is stationary in the circumferential direction regardless of the rotation and the stationary state of the substrate 9. At the bottom of the cup portion 4, a drainage port (not shown) for discharging the processing liquid and the like received by the cup portion 4 to the outside of the substrate processing apparatus 1 is provided. The cup unit 4 moves in the vertical direction between a processing position, which is a position around the substrate 9 shown in FIG. 1, and a retracted position below the processing position by a lifting mechanism (not shown).

  FIG. 3 is a block diagram showing the processing liquid supply unit 5 of the substrate processing apparatus 1. In FIG. 3, configurations other than the treatment liquid supply unit 5 are also shown. The first nozzle 51 is connected to the chemical solution supply source 54 and the rinse solution supply source 55. The second nozzle 52 is connected to the rinse liquid supply source 55 and the solvent supply source 56 via the mixing unit 71. The third nozzle 53 is connected to the filler solution supply source 57. The fourth nozzle 64 is connected to the solvent supply source 56.

  The first nozzle 51 supplies the chemical solution delivered from the chemical solution supply source 54 to the central portion of the upper surface 91 of the substrate 9. For example, a cleaning solution containing dilute hydrofluoric acid (DHF) is used as the chemical solution. In the present embodiment, DHF is used as a chemical solution. Note that, from the chemical solution supply source 54, another type of cleaning solution or a chemical solution other than the cleaning solution may be delivered to the first nozzle 51. Further, the first nozzle 51 supplies the rinse liquid supplied from the rinse liquid supply source 55 to the central portion of the upper surface 91 of the substrate 9 in a state where the supply of the chemical liquid from the chemical liquid supply source 54 is stopped. As the rinse solution, for example, an aqueous treatment solution such as DIW (De-ionized Water), carbonated water, ozone water or hydrogen water is used. In the present embodiment, DIW is used as a rinse solution.

  The first nozzle 51 is included in a chemical solution supply unit that supplies a chemical solution to the upper surface 91 of the substrate 9. The chemical solution supply unit may also include the above-described chemical solution supply source 54. The first nozzle 51 is also included in the rinse liquid supply unit that supplies the rinse liquid to the upper surface 91 of the substrate 9. The rinse liquid supply unit may also include the above-described rinse liquid supply source 55. At the lower end of the first nozzle 51, for example, a discharge port for a chemical solution and a discharge port for a rinse liquid are individually provided, and different types of processing liquids are transferred through different pipes and discharge ports to the substrate 9 Is supplied to the upper surface 91 of the Further, the first nozzle 51 may include a treatment liquid nozzle for a chemical solution and a treatment liquid nozzle for a rinse solution.

  The mixing unit 71 mixes the rinse liquid (i.e., the aqueous solvent) delivered from the rinse liquid source 55 with the solvent delivered from the solvent source 56 to be used in the substitution process described later. A substitution solution is produced. The replacement solution is a diluted solvent obtained by diluting the solvent with a rinse solution. As the solvent, for example, a water-soluble organic solvent such as IPA (isopropyl alcohol), methanol, ethanol, acetone, PGEE (propylene glycol ethyl ether), PGME (propylene glycol methyl ether) or EL (ethyl lactate) is used. . The solvent has lower surface tension than the above-mentioned rinse solution. In the present embodiment, IPA is used as a solvent. That is, the replacement liquid generated in the mixing unit 71 is a diluted IPA obtained by diluting IPA with DIW. The surface tension of the substitution liquid is also smaller than the surface tension of the rinse liquid.

  The mixing unit 71 may be, for example, a static mixer (that is, a static mixer) having no driving unit, and is a dynamic mixer that stirs and mixes the rinse liquid and the solvent by rotating a stirring blade or the like. May be In addition, the mixing unit 71 temporarily stores one of the rinse liquid and the solvent in the storage tank, and supplies the other processing liquid to the one processing liquid in the storage tank, thereby removing the rinse liquid. And a solvent may be mixed.

  The second nozzle 52 is a substitution liquid discharger that discharges the substitution liquid delivered from the mixing section 71 toward the central portion of the upper surface 91 of the substrate 9. The second nozzle 52 and the mixing unit 71 are included in the substitution liquid supply unit 7 that supplies substitution liquid to the upper surface 91 of the substrate 9. The substitution liquid supply unit 7 may also include a rinse liquid supply source 55 and a solvent supply source 56.

  The mixing ratio adjusting unit 72 adjusts the ratio of the solvent to be mixed with the rinse liquid in the mixing unit 71. In the example shown in FIG. 3, the mixing ratio adjusting unit 72 includes valves 721 and 722. The valve 721 is disposed between the rinse liquid supply source 55 and the mixing unit 71, and changes the flow rate of the rinse liquid supplied from the rinse liquid supply source 55 to the mixing unit 71. The valve 722 is disposed between the solvent supply source 56 and the mixing unit 71, and changes the flow rate of the solvent supplied from the solvent supply source 56 to the mixing unit 71.

  The concentration control unit 73 controls the mixing ratio adjusting unit 72 to set the ratio of the solvent mixed in the rinse liquid in the mixing unit 71 to a desired ratio. In other words, the concentration control unit 73 adjusts the component of the substitution solution generated in the mixing unit 71 to a desired one. In the substrate processing apparatus 1, the flow rates of the rinse liquid and the solvent are adjusted by the mixing ratio adjustment part 72 to maintain the ratio of the solvent mixed in the rinse liquid, and the substitution liquid delivered from the mixing part 71 The flow rate can also be changed. The concentration control unit 73 and the mixing ratio adjustment unit 72 are included in the above-described substitution solution supply unit 7.

  The third nozzle 53 supplies the filler solution delivered from the filler solution supply 57 to the central portion of the upper surface 91 of the substrate 9. The filler solution is a solution in which a solid solute is dissolved in a solvent. As the solute, a water soluble polymer (hereinafter simply referred to as "polymer") is used. That is, the filler solution is a water-soluble polymer solution. The said polymer is water-soluble polymer resin, such as an acrylic resin, for example. The solvent of the filler solution is aqueous, for example DIW, PGEE, PGME or EL is utilized. The filler solution has a higher specific gravity than the above-mentioned substitution solution.

  The filler solution is a coating solution applied to the upper surface 91 of the substrate 9. The polymer in the film of the filler solution applied on the upper surface 91 of the substrate 9 (that is, the coating film) is solidified by the evaporation of the solvent. Alternatively, the substrate 9 may be heated to remove residual solvent components in the polymer. The third nozzle 53 is included in a coating liquid supply unit that supplies the coating liquid to the upper surface 91 of the substrate 9 to form a coating film, which is a film of the coating liquid, on the upper surface 91. The coating solution supply unit may also include the filler solution supply 57 described above.

  The fourth nozzle 64 discharges the solvent (i.e., stripping solution) delivered from the solvent supply source 56 toward the outer edge of the lower surface 92 of the substrate 9. The stripping solution supplied from the fourth nozzle 64 to the lower surface 92 of the substrate 9 wraps around the upper surface 91 via the side surface (i.e., outer edge) of the substrate 9 and is supplied to the peripheral region 93 (i.e., edge portion) of the upper surface 91 Be done. The fourth nozzle 64 is included in the peeling liquid supply unit that supplies the peeling liquid to the peripheral area 93 of the upper surface 91 of the substrate 9. The stripping solution supply may also include a solvent supply 56.

  FIG. 4 is a plan view showing the substrate 9. In FIG. 4, in order to facilitate the understanding of the figure, the upper surface 91 of the substrate 9 is hatched on the inner region 94 which is the radially inner region of the peripheral region 93, and the peripheral region 93 and the inner region 94 The boundary of is indicated by a two-dot chain line. On the upper surface 91 of the substrate 9, a structure (for example, a circuit pattern used in a product), which is a collection of a large number of fine structure elements, is formed in advance in the inner region 94. The structure is not formed in the peripheral area 93.

  The processing of the substrate 9 in the substrate processing apparatus 1 is performed, for example, in the order of chemical solution processing, rinse processing, replacement processing, filler filling processing, peeling processing (that is, edge rinse processing) and drying processing. FIG. 5 is a view showing an example of the flow of processing of the substrate 9 in the substrate processing apparatus 1. FIG. 6 is a view showing an example of the rotational speed during processing of the substrate 9. The horizontal axis in FIG. 6 is independent of the actual processing time.

  First, the substrate 9 having the above-described structure formed on the upper surface 91 is held horizontally by the substrate holding unit 31 (step S11). Subsequently, the rotation of the substrate 9 is started, and the chemical solution is supplied from the first nozzle 51 to the substrate 9 rotating at a relatively high rotation speed (for example, 800 rpm). Then, the supply of the chemical solution is continued for a predetermined time to perform the chemical solution process on the substrate 9 (step S12). In the present embodiment, DHF is used as a chemical solution, and the upper surface 91 of the substrate 9 is cleaned. Thereby, the upper surface 91 of the substrate 9 becomes a hydrophobic surface.

  During chemical liquid processing on the substrate 9, the cover plate 35 is located at the first position, and an air flow of inert gas from the inside in the radial direction toward the outside in the radial direction is formed in the gap between the substrate 9 and the cover plate 35 It is done. Thereby, the chemical solution supplied to the upper surface 91 of the substrate 9 is prevented or suppressed from flowing around to the lower surface 92 via the side surface of the substrate 9.

  When the supply of the chemical solution is stopped, the rinse liquid is supplied from the first nozzle 51 to the substrate 9 rotating at a relatively high rotational speed (for example, 800 rpm as in step S12). Then, the supply of the rinse liquid is continued for a predetermined time to perform the rinse process on the substrate 9 (step S13). In the rinse process, the chemical solution on the substrate 9 is washed away by the rinse solution (for example, DIW) supplied from the first nozzle 51. During the rinsing process for the substrate 9, the cover plate 35 is located at the first position, and an air flow of inert gas is formed in the gap between the substrate 9 and the cover plate 35 from the radially inner side toward the radially outer direction. It is done. Thereby, the rinse liquid supplied to the upper surface 91 of the substrate 9 is prevented or suppressed from flowing around to the lower surface 92 via the side surface of the substrate 9.

  In the substrate processing apparatus 1, for example, in parallel with the rinse processing of the substrate 9, the rinse liquid, which is an aqueous solvent, and the solvent, which is a water-soluble organic solvent, are mixed in the mixing unit 71 to generate a substitution liquid (step S 14 ). In step S14, as described above, the proportion of the solvent mixed with the rinse liquid in the mixing unit 71 can be adjusted. Specifically, input information related to the process of forming the coating film is stored in advance in the concentration control unit 73, and the mixing control unit 73 is controlled by the concentration control unit 73 based on the input information. The proportion of solvent mixed into the rinse solution is adjusted.

  The input information includes, for example, the type of the filler solution that forms the coating film, the property of the upper surface 91 of the substrate 9, the type of the above-described chemical solution processing, and the like. In step S14, the volume concentration of the solvent in the replacement solution is preferably 15% or more and 30% or less. In other words, the volume mixing ratio of the solvent and the rinse liquid when the substitution liquid is generated in the mixing unit 71 is 3:17 to 3: 7. The volume concentration of the solvent in the substitution solution may be less than 15% or more than 30%.

  When steps S13 and S14 are finished, the supply of the rinse liquid is stopped while the rotational speed of the substrate 9 is gradually decreased, and the substitution liquid is supplied from the second nozzle 52 to the upper surface 91 of the substrate 9. At this time, the rotation speed of the substrate 9 is a rotation speed sufficiently lower than the above-mentioned rotation speed. The rotational speed of the substrate 9 is, for example, 0 rpm to 10 rpm. The substitution liquid supplied onto the substrate 9 spreads radially outward from the central portion of the upper surface 91.

  Then, the rotational speed of the substrate 9 is gradually increased to a relatively high rotational speed (for example, 800 rpm) while continuing the supply of the substitution liquid to the substrate 9. As a result, the substitution liquid spreads radially outward from the central portion of the upper surface 91 of the substrate 9, and the rinse liquid on the substrate 9 moves radially outward. Then, the rinse liquid is removed from above the substrate 9 (that is, the rinse liquid is replaced by the replacement liquid), and a thin liquid film of the replacement liquid (hereinafter referred to as “substitution liquid film”) is formed on the upper surface 91 of the substrate 9. Is formed and held. In the substrate processing apparatus 1, the rotational speed of the substrate 9 when the replacement liquid film is formed is set such that the thickness of the replacement liquid film becomes a desired thickness.

  Since the substitution liquid has a low surface tension, it easily enters gaps in the structure of the upper surface 91 of the substrate 9 (that is, the space between adjacent structure elements in the structure). Therefore, the gap in the structure is filled with the replacement liquid (step S15). The substitution liquid film has a thickness that substantially covers at least the height of the structure or more. When the replacement process of the rinse solution by the replacement solution is completed, the supply of the replacement solution is stopped.

  Also during the supply of the substitution liquid to the substrate 9, the cover plate 35 is at the first position, and an air flow of the inert gas from the radially inner side toward the radially outer direction into the gap between the substrate 9 and the cover plate 35 Is formed. Thereby, the substitution liquid supplied to the upper surface 91 of the substrate 9 is prevented or suppressed from flowing around to the lower surface 92 via the side surface of the substrate 9.

  If the replacement liquid used in step S15 is produced by mixing the aqueous solvent and the water-soluble organic solvent, the rinse liquid from the rinse liquid source 55 and the solvent from the solvent source 56 are not necessarily required. And does not have to be generated by mixing. For example, an aqueous solvent supplied from a source different from the rinse liquid source 55 and a water-soluble organic solvent supplied from a source different from the solvent source 56 are mixed in the mixing unit 71 and the substitution liquid May be generated. The above-mentioned aqueous solvent may be a liquid of a type different from that of the rinse liquid delivered from the rinse liquid supply source 55 (for example, carbonated water, ozone water or hydrogen water). The water-soluble organic solvent may also be a liquid of a type different from the solvent delivered from the solvent supply source 56 (eg, PGEE, PGME, EL, methanol, ethanol or acetone).

  When step S15 is completed, the third nozzle 53 supplies a filler solution, which is a coating liquid, to the rotating substrate 9 while maintaining the relatively high rotational speed in step S15. When a predetermined amount of filler solution is supplied onto the substrate 9, the supply of the filler solution is stopped. The filler solution supplied from the third nozzle 53 to the substitution liquid film on the substrate 9 spreads radially outward from the central portion of the upper surface 91 by the rotation of the substrate 9. Thereby, a liquid film of the filler solution is formed on the substitution liquid film on the substrate 9. The number of rotations of the substrate 9 when the liquid film of the filler solution is formed does not have to be maintained constant, and may be appropriately changed. For example, the filler solution may be supplied in a state in which the rotation of the substrate 9 is stopped, and then the liquid solution film of the filler solution may be formed on the substitution liquid film by rotating the substrate 9.

  Thereafter, the rotational speed of the substrate 9 is reduced, for example, to 10 rpm. As described above, substantially the entire upper surface 91 of the substrate 9 is covered by the substitution liquid film, and substantially the entire upper surface of the substitution liquid film is covered by the liquid film of the filler solution. Since the specific gravity of the filler solution is larger than that of the replacement solution, the upper and lower sides of the replacement solution film and the solution film of the filler solution are switched. Thereby, the substitution solution present in the gap in the structure on the upper surface 91 of the substrate 9 is replaced by the filler solution, and the gap in the structure is filled with the filler solution (step S16). In other words, step S16 is a filler filling process (i.e., filler embedding process) for embedding the filler between the adjacent structural elements in the structure. On the substrate 9, the liquid film of the filler solution is positioned on the upper surface 91, and the substitution liquid film is positioned on the liquid film of the filler solution.

  When step S16 is completed, the rotation speed of the substrate 9 is increased, and the substitution liquid film on the liquid film of the filler solution is removed from the substrate 9. In addition, the excess of the filler solution is also removed from the substrate 9. At this time, the rotational speed of the substrate 9 is such that the filler embedded in the gap (i.e., between adjacent structure elements) in the structure of the substrate 9 in step S16 does not come out due to the centrifugal force. It is speed. For example, the substrate 9 is rotated at 300 rpm to 500 rpm. Thereby, a coating film which is a liquid film of the filler solution is formed on the upper surface 91 of the substrate 9 (step S17). The coating film has a thickness necessary to cover the entire structure. On the substrate 9, the solidification of the coating film proceeds by the evaporation of the solvent contained in the filler solution.

  During supply of the filler solution to the substrate 9, the cover plate 35 is rotated by the substrate rotation mechanism 33 together with the substrate 9 and the substrate holder 31 at the second position. Thereby, the treatment liquid (for example, a chemical solution, a rinse liquid or a substitution liquid) adhering to the cover plate 35 moves outward in the radial direction and scatters outward from the outer edge of the cover plate 35 in the radial direction.

  Subsequently, in a state where the substrate 9 is rotated, the peeling liquid is discharged from the fourth nozzle 64 toward the outer edge portion of the lower surface 92 of the substrate 9. The rotational speed of the substrate 9 may be, for example, 300 to 500 rpm as in step S17, and may be gradually increased to a speed higher than the rotational speed of step S17. The stripping solution supplied from the fourth nozzle 64 to the lower surface 92 of the substrate 9 goes around the upper surface 91 via the side surface of the substrate 9 and extends around the entire peripheral region 93 of the upper surface 91 of the substrate 9 during rotation. Supplied. Thereby, a peeling process is performed in which a portion on the peripheral region 93 of the coating film (that is, the liquid film of the filler solution) on the upper surface 91 of the substrate 9 is peeled from the substrate 9 and removed (step S18). In step S18, in addition to the peripheral area 93 of the upper surface 91 of the substrate 9, the filler solution adhering to the side edge of the substrate 9 and the outer edge of the lower surface 92 is also removed. During the peeling process on the substrate 9, the cover plate 35 is at the first position.

  When step S18 is completed, the substrate 9 is dried (step S19). In step S19, with the substrate 9 held by the substrate holding unit 31, the substrate holding unit 31 is rotated at high speed. As a result, the peeling liquid applied to the peripheral region 93 of the substrate 9 is scattered radially outward from the outer edge of the substrate 9 by the centrifugal force, and is removed from above the substrate 9. A processing solution such as a chemical solution, a rinse solution, a replacement solution, a filler solution, and a release solution which is scattered outward in the radial direction from above the substrate 9 during the above steps S12 to S19 is received by the cup portion 4 and the substrate processing apparatus It is discharged to the outside of 1.

  The substrate 9 for which the drying process has been completed is unloaded from the substrate processing apparatus 1 and transported to the next processing apparatus (not shown). Then, the substrate 9 is heated by the next processing apparatus, and a process of solidifying the filler embedded in the gap (that is, between adjacent structure elements) in the structure on the substrate 9 is performed. When the substrate 9 is transported from the substrate processing apparatus 1 to the next processing apparatus, the filler in the peripheral area 93 of the substrate 9 is removed, so that the transport mechanism is prevented from being contaminated by the filler. Ru. In the substrate processing apparatus 1, the above-described processes of steps S 11 to S 19 are sequentially performed on a plurality of substrates 9.

  As described above, the substrate processing apparatus 1 includes the substrate holding unit 31, the rinse liquid supply unit, the replacement liquid supply unit 7, and the coating liquid supply unit. The substrate holding unit 31 holds the substrate 9 in a horizontal state. The rinse liquid supply unit supplies the rinse liquid to the upper surface 91 of the substrate 9. The substitution liquid supply unit 7 supplies the substitution liquid to the upper surface 91 of the substrate 9 to replace the rinse liquid on the upper surface 91 of the substrate 9 with the substitution liquid, and the substitution liquid film which is a liquid film of the substitution liquid is Form on 91. The coating liquid supply unit supplies a coating liquid (that is, a filler solution) that is a water-soluble polymer solution onto the substitution liquid film, and forms a coating film that is a film of the coating liquid on the upper surface 91 of the substrate 9. The substitution liquid supply unit 7 includes a mixing unit 71 and a second nozzle 52 which is a substitution liquid ejection unit. The mixing unit 71 mixes the water-soluble organic solvent and the aqueous solvent, and generates a replacement liquid having a surface tension smaller than that of the rinse liquid. The second nozzle 52 discharges the substitution liquid delivered from the mixing unit 71 toward the substrate 9.

  Thus, the water-soluble organic solvent and the aqueous solvent are mixed to form a replacement liquid having a surface tension smaller than that of the rinse liquid, and the replacement liquid on the substrate 9 is replaced with the replacement liquid to obtain the substrate 9. The upper surface 91 can be suitably coated with a substitution liquid film. Thereby, it is possible to prevent the upper surface 91 of the substrate 9 from being exposed from the rinse liquid film and coming into contact with the outside air between the rinse processing and the filler filling processing. In other words, the upper surface 91 of the substrate 9 can be prevented from being exposed from the liquid film before the formation of the coating film. Further, as described above, since the substitution solution contains an aqueous solvent, it is possible to prevent the filler solution from being aggregated in the substitution solution film. As a result, a coating film can be suitably formed on the substrate 9.

  The substrate processing apparatus 1 further includes a substrate rotation mechanism 33. The substrate rotation mechanism 33 rotates the substrate 9 together with the substrate holding unit 31 about a central axis J1 which is directed in the vertical direction. In the substrate processing apparatus 1, the substrate rotation mechanism 33 rotates the substrate 9 when the replacement liquid film is formed (step S <b> 15). Thereby, the thickness of the substitution liquid film can be easily made to a desired thickness. As a result, since the thickness of the substitution liquid film can be prevented from becoming excessively large, the amount of the filler solution supplied to the substitution liquid film in step S16 can be reduced.

  As described above, the substitution liquid supply unit 7 further includes the mixing ratio adjusting unit 72 that adjusts the ratio of the water-soluble organic solvent to be mixed with the aqueous solvent in the mixing unit 71. Thereby, the preferable volume concentration of the water-soluble organic solvent in the replacement liquid can be easily made in accordance with the type of the filler solution forming the coating film, the property of the upper surface 91 of the substrate 9, the type of the chemical treatment described above, etc. It can be realized.

  In addition, the substitution liquid supply unit 7 further includes a concentration control unit 73 that controls the mixing ratio adjustment unit 72 based on input information on the forming process of the coating film. Thereby, the volume concentration of the water-soluble organic solvent in the replacement liquid is automatically adjusted in accordance with the type of the filler solution forming the coating film, the property of the upper surface 91 of the substrate 9, the type of the chemical treatment described above, etc. It can be adjusted.

  As described above, the volume concentration of the water-soluble organic solvent in the substitution solution is preferably 15% or more and 30% or less. Thereby, the prevention of the exposure of the upper surface 91 of the substrate 9 and the formation of the coating film on the substrate 9 can be suitably achieved.

  7 and 8 show experimental results in the first embodiment and the second embodiment, respectively. In the first and second embodiments, the above-described steps S11 to S17 are performed on the substrate 9 with respect to a plurality of volume concentrations of the water-soluble organic solvent in the replacement liquid. The processing conditions are the same between the first embodiment and the second embodiment except that the type of filler contained in the filler solution is different. The circle marks in the drawing indicate that the exposure prevention of the upper surface 91 of the substrate 9 or the formation of the coating film on the substrate 9 is suitably performed. The x marks in the drawing indicate that the upper surface 91 of the substrate 9 is exposed or that the coating film is not suitably formed on the substrate 9. The Δ marks in the figure indicate the state in between the 印 marks and the X marks. From FIGS. 7 and 8, by setting the volume concentration of the water-soluble organic solvent in the substitution solution to 15% or more and 30% or less, the exposure of the upper surface 91 of the substrate 9 is prevented, and the formation of the coating film on the substrate 9 It can be seen that it is possible to preferably achieve both.

  In the substrate processing apparatus 1, the above-mentioned water-soluble organic solvent is IPA. Thus, the structure related to the generation of the substitution liquid is simplified by generating the substitution liquid using IPA used also for other processing (in the above example, peeling processing) of the substrate 9 in the substrate processing apparatus 1 be able to. As a result, the structure of the substrate processing apparatus 1 can be simplified.

  As described above, the rinse liquid delivered from the rinse liquid source 55 is the same type of liquid as the aqueous solvent of the substitution liquid. Thereby, the structure regarding the production | generation of a substitution liquid can be simplified, As a result, the structure of the substrate processing apparatus 1 can also be simplified. Also, the solvent delivered from the solvent supply source 56 is the same type of liquid as the water-soluble organic solvent of the substitution liquid. Therefore, the structure of the substrate processing apparatus 1 can be further simplified.

  As described above, the structure is previously formed on the upper surface 91 of the substrate 9. Then, in the substrate processing apparatus 1, the above-described coating film is formed on the upper surface 91 of the substrate 9, whereby the gap in the structure is filled with the coating liquid. As a result, collapse of the structure due to the surface tension of the treatment liquid acting on the structure can be prevented or suppressed.

  In the substrate processing apparatus 1, the upper surface 91 of the substrate 9 immediately before the supply of the replacement liquid is started in step S15 is a hydrophobic surface. Therefore, by switching the rinse solution supplied on the substrate 9 to the substitution solution, it is possible to preferably prevent the upper surface 91 of the substrate 9 from being exposed from the liquid film before the formation of the coating film.

  Various modifications can be made to the substrate processing apparatus 1 described above.

  For example, in the above-described example, the upper surface 91 of the substrate 9 becomes a hydrophobic surface by performing the cleaning process with DHF on the substrate 9, but the upper surface 91 of the substrate 9 is the original due to the material etc. of the substrate 9. Even in the case of the hydrophobic surface, in the substrate processing apparatus 1, both the prevention of the exposure of the upper surface 91 of the substrate 9 and the formation of the coating film on the substrate 9 can be compatible. The substrate processing apparatus 1 may be used to process a substrate 9 whose upper surface 91 is not a hydrophobic surface (that is, a hydrophilic surface).

  In the substrate processing apparatus 1, the substrate 9 may stand still without rotating when forming the substitution film in step S15. In this case, the substrate rotation mechanism 33 may be omitted from the substrate processing apparatus 1.

  In the substitution liquid supply unit 7, the concentration control unit 73 may be omitted. In this case, the ratio of the water-soluble organic solvent to be mixed with the aqueous solvent in the mixing unit 71 is adjusted by the operator operating the mixing ratio adjusting unit 72 based on the input information such as the type of the filler solution. . Further, in the substitution liquid supply unit 7, the proportion of the water-soluble organic solvent mixed with the aqueous solvent may be constant. In this case, the mixing ratio adjusting unit 72 may be omitted.

  The above-mentioned substrate processing apparatus 1 is used for a glass substrate used for flat display devices (Flat Panel Display) such as liquid crystal display devices or organic EL (Electro Luminescence) display devices other than semiconductor substrates, or other display devices. It may be used for processing of the glass substrate to be processed. The substrate processing apparatus 1 described above may be used to process an optical disk substrate, a magnetic disk substrate, a magneto-optical disk substrate, a photomask substrate, a ceramic substrate, a solar cell substrate, and the like.

  The configurations in the above embodiment and each modification may be combined as appropriate as long as no contradiction arises.

DESCRIPTION OF SYMBOLS 1 substrate processing apparatus 7 substitution liquid supply unit 9 substrate 31 substrate holding unit 33 substrate rotation mechanism 51 first nozzle 52 second nozzle 53 third nozzle 71 mixing unit 72 mixing ratio adjusting unit 73 concentration control unit 91 (surface of substrate) J1 Central axis S11 to S19 step

Claims (18)

A substrate processing method for processing a substrate, comprising
a) holding the substrate in a horizontal state;
b) supplying a rinse liquid to the upper surface of the substrate;
c) mixing a water-soluble organic solvent and an aqueous solvent to form a substitution solution having a smaller surface tension than the rinse solution;
d) After the step b) and the step c), the rinse solution on the upper surface of the substrate is replaced with the replacement solution by supplying the replacement solution to the upper surface of the substrate to replace the replacement solution. Forming a replacement liquid film, which is a liquid film of liquid, on the upper surface;
e) supplying a coating solution, which is a water-soluble polymer solution, onto the substitution film after the step d), and forming a coating, which is a film of the coating solution, on the upper surface of the substrate; ,
A substrate processing method comprising: The substrate processing method according to claim 1,
A substrate processing method characterized in that, in the step d), the substrate is rotated about a central axis directed in the vertical direction. The substrate processing method according to claim 1 or 2, wherein
A substrate processing method characterized in that the ratio of the water-soluble organic solvent to be mixed with the aqueous solvent is adjustable in the step c). The substrate processing method according to claim 3,
A substrate processing method characterized in that, in the step c), the proportion of the water-soluble organic solvent to be mixed with the aqueous solvent is adjusted based on input information on the forming process of the coating film. The substrate processing method according to any one of claims 1 to 4, wherein
The volume concentration of the water-soluble organic solvent in the substitution solution is 15% or more and 30% or less. The substrate processing method according to any one of claims 1 to 5, wherein
The substrate processing method, wherein the water-soluble organic solvent is isopropyl alcohol. The substrate processing method according to any one of claims 1 to 6, wherein
The substrate processing method, wherein the rinse liquid is a liquid of the same type as the aqueous solvent of the replacement liquid. The substrate processing method according to any one of claims 1 to 7, wherein
A structure is previously formed on the upper surface of the substrate,
In the step e), a gap in the structure is filled with the coating solution. The substrate processing method according to any one of claims 1 to 8, wherein
A substrate processing method characterized in that the upper surface of the substrate immediately before the supply of the substitution liquid is started in the step d)) is a hydrophobic surface. A substrate processing apparatus for processing a substrate, wherein
A substrate holding unit that holds the substrate in a horizontal state;
A rinse liquid supply unit that supplies a rinse liquid to the upper surface of the substrate;
By supplying a substitution liquid to the upper surface of the substrate, the rinse liquid on the upper surface of the substrate is substituted with the substitution liquid to form a substitution liquid film, which is a liquid film of the substitution liquid, on the upper surface A substitution solution supply unit,
A coating solution supply unit for supplying a coating solution, which is a water-soluble polymer solution, onto the substitution film and forming a coating film, which is a film of the coating solution, on the upper surface of the substrate;
Equipped with
The substitution solution supply unit
A mixing unit which mixes a water-soluble organic solvent and an aqueous solvent and produces the substitution solution having a smaller surface tension than the rinse solution;
A substitution liquid discharger that discharges the substitution liquid delivered from the mixing unit toward the substrate;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 10, wherein
The apparatus further comprises a substrate rotation mechanism that rotates the substrate together with the substrate holding unit around a central axis facing in the vertical direction.
A substrate processing apparatus, wherein the substrate is rotated by the substrate rotation mechanism when the substitution liquid film is formed. 12. The substrate processing apparatus according to claim 10, wherein
The substrate processing apparatus, wherein the substitution liquid supply unit further includes a mixing ratio adjusting unit that adjusts a ratio of the water-soluble organic solvent to be mixed with the aqueous solvent in the mixing unit. The substrate processing apparatus according to claim 12, wherein
The substrate processing apparatus, further comprising: a concentration control unit configured to control the mixing ratio adjusting unit on the basis of input information related to a forming process of the coating film, the substitution liquid supply unit. The substrate processing apparatus according to any one of claims 10 to 13, wherein
The volume concentration of the water-soluble organic solvent in the substitution liquid is 15% or more and 30% or less. The substrate processing apparatus according to any one of claims 10 to 14, wherein
The substrate processing apparatus, wherein the water-soluble organic solvent is isopropyl alcohol. The substrate processing apparatus according to any one of claims 10 to 15, wherein
The substrate processing apparatus, wherein the rinse liquid is a liquid of the same type as the aqueous solvent of the replacement liquid. The substrate processing apparatus according to any one of claims 10 to 16, wherein
A structure is previously formed on the upper surface of the substrate,
A substrate processing apparatus characterized in that a gap in the structure is filled with the coating liquid by forming the coating film on the upper surface of the substrate. The substrate processing apparatus according to any one of claims 10 to 17, wherein
A substrate processing apparatus, wherein the upper surface of the substrate immediately before the supply of the substitution liquid is started is a hydrophobic surface.

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