Substrate processing method and substrate processing apparatus

Abstract

The present invention provides a substrate processing method and a substrate processing apparatus, which can remove the upper ends of convex portions in a substrate having concave and convex portions formed on its surface and can suppress damage to the concave portions. The substrate processing method according to the embodiment is a substrate processing method for removing the upper ends of convex portions in a substrate having concave and convex portions formed on its surface. The substrate processing method includes: a step of supplying a first liquid to the surface of the substrate on which the concave and convex portions are formed; a step of forming a protective layer covering the surface of the substrate from the first liquid supplied to the surface of the substrate; a step of supplying a second liquid onto the protective layer; and a step of physically removing the protective layer located at the upper ends of the convex portions to bring the second liquid into contact with the upper ends of the convex portions from which the protective layer has been removed.

Description

Technical Field

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

[0002] In the manufacturing processes of semiconductor devices, flat panel displays, etc., sometimes uneven portions such as patterns are formed on the surface of a substrate. Also, sometimes a process of removing the upper ends of the convex portions formed on the surface of the substrate is performed.

[0003] For example, by CMP (Chemical Mechanical Polishing) processing, the upper ends of the convex portions are chemically and mechanically removed. However, in CMP processing, since the polishing pad directly contacts the surface of the substrate for polishing, when removing the upper ends of the convex portions, for example, it is possible to damage the side walls, bottoms, etc. of the concave portions. Also, the abrasive may remain inside the concave portions, and subsequent processes may become difficult due to the abrasive remaining inside the concave portions.

[0004] In addition, for example, by dry etching processing using high-density plasma, the upper ends of the convex portions are removed. Although dry etching processing has relatively excellent fine processability, the etching progresses into the inside of the concave portions, and for example, it is possible to damage the side walls, bottoms, etc. of the concave portions.

[0005] In addition, for example, by wet etching processing, the upper ends of the convex portions are chemically removed. However, in wet etching processing, since the chemical solution also penetrates into the inside of the concave portions, for example, it is possible to damage the side walls, bottoms, etc. of the concave portions.

[0006] In addition, for example, a technique has been proposed in which a concavo-convex member that functions as a catalyst is pressed against the surface of a substrate, and at the same time, a chemical solution is supplied to the surface of the substrate to remove the upper ends of the convex portions (for example, refer to Patent Document 1). However, since portions that do not come into contact with the concavo-convex member that functions as a catalyst are not removed, there may be a remaining portion on the surface of the substrate. Also, due to the chemical solution that penetrates into the inside of the concave portions, for example, it is possible to damage the side walls, bottoms, etc. of the concave portions.

[0007] Therefore, it is desired to develop a technique that can remove the upper ends of the convex portions in a substrate having uneven portions on its surface and can suppress damage to the concave portions.

[0008] Patent Document

[0009] Patent Document 1: Japanese Patent Application Laid-Open No. 2019-054227 Summary of the Invention

[0010] The technical problem to be solved by the present invention is to provide a substrate processing method and a substrate processing apparatus that can remove the upper ends of protrusions in a substrate having uneven portions on its surface and can suppress damage to the recessed portions.

[0011] The substrate processing method according to the embodiment is a substrate processing method for removing the upper ends of protrusions in a substrate having uneven portions on its surface. The substrate processing method includes: a step of supplying a first liquid to the surface of the substrate having uneven portions; a step of forming a protective layer covering the surface of the substrate from the first liquid supplied to the surface of the substrate; a step of supplying a second liquid onto the protective layer; and a step of physically removing the protective layer located at the upper ends of the protrusions to bring the second liquid into contact with the upper ends of the protrusions from which the protective layer has been removed.

[0012] According to an embodiment of the present invention, there is provided a substrate processing method and a substrate processing apparatus that can remove the upper ends of protrusions in a substrate having uneven portions on its surface and can suppress damage to the recessed portions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic cross-sectional view for illustrating a substrate.

[0014] Figure 2 is a schematic process cross-sectional view for illustrating a substrate processing method.

[0015] Figure 3 (a) and (b) are schematic process cross-sectional views for illustrating a substrate processing method.

[0016] Figure 4 (a) and (b) are schematic process cross-sectional views for illustrating a substrate processing method.

[0017] Figure 5 (a) and (b) are schematic process cross-sectional views for illustrating a substrate processing method.

[0018] Figure 6 is a schematic process cross-sectional view for illustrating a substrate processing method.

[0019] Figure 7 is a schematic process cross-sectional view for illustrating a substrate processing method.

[0020] Figure 8 is a schematic diagram for illustrating a substrate processing apparatus.

[0021] REFERENCE SIGNS

[0022] 1 - Substrate processing apparatus; 10 - Placement unit; 20 - Liquid supply unit; 21 - First supply unit; 22 - Second supply unit; 23 - Third supply unit; 24 - Fourth supply unit; 30 - Removal unit; 31 - Removal member; 32 - Driving unit; 33 - Cleaning unit; 34 - Cleaning unit; 40 - Controller; 100 - Substrate; 100a - Surface; 102 - First layer; 102a - Recess; 103 - Second layer; 105 - First liquid; 105a - Protective layer; 105b - Protective layer; 106 - Second liquid; 107 - Third liquid; 108 - Fourth liquid. Detailed implementation mode

[0023] Hereinafter, the implementation modes will be illustrated with reference to the accompanying drawings. In addition, in each of the drawings, the same reference numerals are assigned to the same components and the detailed description is appropriately omitted.

[0024] Structure of the substrate

[0025] First, the substrate 100 processed by the substrate processing method and the substrate processing apparatus 1 according to this implementation mode will be described.

[0026] Figure 1 It is a schematic cross-sectional view for illustrating the substrate 100.

[0027] Moreover, hereinafter, as an example, the case where the substrate 100 is a semiconductor substrate such as a wafer will be described. However, the substrate 100 is not limited to a semiconductor substrate, and for example, it can also be a substrate for a flat display such as a liquid crystal panel or a micro-structured body such as MEMS (MicroElectro Mechanical Systems).

[0028] As Figure 1 shown, the substrate 100 has, for example, a base 101, a first layer 102, a second layer 103, and a third layer 104.

[0029] The base 101 is plate-shaped and contains a semiconductor material such as silicon.

[0030] The first layer 102 is provided, for example, in at least a part of a region on one surface of the base 101. The first layer 102 can be, for example, an insulating layer. The insulating layer can be formed, for example, by oxidizing the surface of the base 101 or forming an oxide film, nitride film, oxynitride film, etc. on the base 101. The insulating layer can contain, for example, silicon oxide. In addition, the first layer 102 can also be, for example, a laminated film in which an insulating layer, a semiconductor layer, a conductor layer, etc. are laminated. When the first layer 102 is a laminated film, the ends of the insulating layer, semiconductor layer, conductor layer, etc. are exposed on the side walls of the recess 102a.

[0031] At least one recess 102a is provided on the first layer 102. In Figure 1A plurality of recesses 102a are provided on the illustrated substrate 100. The recesses 102a open on the upper surface of the first layer 102. The recesses 102a can be, for example, holes or grooves. The depth of the recesses 102a can be, for example, about 4 μm to 5 μm. The opening size of the recesses 102a (for example, the hole diameter or the groove width) can be, for example, about 100 nm.

[0032] The recesses 102a can be formed, for example, by a plasma etching process such as RIE (Reactive Ion Etching). When performing the plasma etching process, the second layer 103 provided on the first layer 102 can be used as an etching mask.

[0033] The second layer 103 is provided on the first layer 102. The second layer 103 has holes communicating with the recesses 102a. The second layer 103 covers the portion of the first layer 102 where the recesses 102a do not open. That is, the second layer 103 can be the upper end of the convex portion provided on the surface of the substrate 100.

[0034] The second layer 103 can be, for example, a metal mask (hard mask). The metal mask can be formed, for example, by etching a film provided on the first layer 102. The second layer 103, i.e., the metal mask, contains at least any one of a metal and a metal oxide. The metal can contain at least any one of tungsten (W), cobalt (Co), ruthenium (Ru), nickel (Ni), iron (Fe), hafnium (Hf), copper (Cu), and chromium (Cr). The metal oxide can be an oxide of these metals.

[0035] In addition, the second layer 103 can also be a resist mask having a modified layer on its surface. For example, during ion implantation or the like, if ions are incident on the surface of the resist mask, it is possible that the surface of the resist mask is modified to form a modified layer. Since the physical and chemical resistance of the modified layer is higher than that of the protective layer, if a modified layer is formed on the surface, it may be difficult to remove by ordinary dry etching or wet etching.

[0036] In addition, a third layer 104 is sometimes provided. The third layer 104 can be, for example, a metal wiring layer, a semiconductor layer, etc. that are exposed at the bottom of the recesses 102a. The third layer 104 can be formed, for example, of a metal or a metal oxide containing at least any one of tungsten, cobalt, ruthenium, nickel, iron, hafnium, copper, and chromium. At this time, the material of the third layer 104 can be the same as or different from the material of the second layer 103.

[0037] In the substrate 100 configured as described above, a plurality of holes of the second layer 103 are opened on its surface 100a. The plurality of holes of the second layer 103 communicate with a plurality of recesses 102a provided on the first layer 102. Therefore, uneven portions are formed on the surface 100a of the substrate 100, and the uneven portions are formed by the plurality of recesses 102a provided on the first layer 102 and the plurality of holes provided on the second layer 103 that communicate with the recesses 102a. Thus, the surface 100a becomes the surface of the substrate 100 on which the uneven portions are formed.

[0038] Moreover, since known techniques can be applied to the configurations or formation methods of the base 101, the first layer 102, the recesses 102a, the second layer 103, and the third layer 104, detailed descriptions thereof are omitted.

[0039] Here, when the substrate 100 is used as a substrate for a micro-structure, the second layer 103 may sometimes not be required. For example, if the second layer 103 is provided, it may be in the way or hinder the function of the substrate 100 in subsequent processes. When removing the second layer 103, the second layer 103 is usually removed by CMP processing, dry etching processing, wet etching processing, or the like.

[0040] However, since it is difficult to remove the second layer 103 when it is a metal mask or a resist mask having a deteriorated layer on its surface, etc., it is necessary to increase the physical removal conditions or chemical reactivity. Therefore, if the second layer 103 is removed by CMP processing, dry etching processing, wet etching processing, or the like, the side walls, bottoms of the recesses 102a, or the third layer 104 may be damaged by abrasive agents, free radicals, ions, etching solutions, or the like. In addition, there is also a possibility that abrasive agents or the like remain inside the recesses 102a.

[0041] Then, in the substrate processing method according to the present embodiment, the second layer 103 is removed as follows.

[0042] Substrate Processing Method

[0043] Next, the substrate processing method according to the present embodiment will be described.

[0044] Figures 2 to 7 It is a schematic process cross-sectional view for illustrating the substrate processing method.

[0045] First, as Figure 2 shown, a first liquid 105 is supplied to the surface of the substrate 100 on the side where the second layer 103 is provided. The first liquid 105 can be ejected from a nozzle or sprayed from a spray nozzle, for example. The supplied first liquid 105 covers the surface of the second layer 103. In addition, the first liquid 105 is also supplied to the inside of the recesses 102a.

[0046] Here, since the protective layers 105a and 105b described later are formed from the first liquid 105, the thickness of the first liquid 105 is controlled so as to form the protective layers 105a and 105b with appropriate thicknesses. For example, the thickness of the first liquid 105 can be controlled by the supply amount (supply time), viscosity of the first liquid 105, or the rotation speed of the substrate 100, etc. For example, the viscosity of the first liquid 105 can be controlled by the type of the volatile corrosion inhibitor described later or the ratio (concentration) of the volatile corrosion inhibitor to the solvent. The thickness of the first liquid 105 can be appropriately determined by conducting experiments and simulations in advance.

[0047] The surface of the first liquid 105 that contacts the substrate 100 is the side where the second layer 103 is provided. Therefore, it is preferable that the first liquid 105 contains a material that is difficult to react with the material of the base 101, the material of the first layer 102, and the material of the third layer 104. In addition, as described later, the protective layers 105a and 105b formed from the first liquid 105 have the function of protecting the surface of the substrate 100 from the second liquid 106 described later. Therefore, it is preferable that the first liquid 105 contains a material that is difficult to react with the second liquid 106. In addition, as described later, since the protective layers 105a and 105b are formed by drying the first liquid 105, it is preferable that the first liquid 105 is a liquid that easily vaporizes.

[0048] The first liquid 105 may contain at least a volatile corrosion inhibitor. Examples of the volatile corrosion inhibitor may include benzo triazole, tolyl triazole (methyl benzotriazole), dicyclohexyl ammonium nitrite, dicyclohexyl ammonium salicylate, monoethanolamine benzoate, dicyclohexyl ammonium benzoate, diisopropyl ammonium benzoate, diisopropyl ammonium nitrite, cyclohexylamine carbamate, nitro naphthalene ammonium nitrite, cyclohexylamine benzoate, dicyclohexyl ammonium cyclohexanecarboxylate, cyclohexylamine cyclohexane carboxylate, dicyclohexylammonium acrylate, cyclohexylamine acrylate, etc.

[0049] When the volatile corrosion inhibitor is a liquid, the volatile corrosion inhibitor can be used as the first liquid 105. At this time, the volatile corrosion inhibitor can be used directly, or a solvent can be added to the volatile corrosion inhibitor for dilution. When the volatile corrosion inhibitor is a solid, the volatile corrosion inhibitor and a solvent can be mixed.

[0050] Preferably, the solvent can dissolve the volatile corrosion inhibitor and is difficult to react with the materials of the base 101, the first layer 102, and the third layer 104. The solvent can be, for example, pure water or alcohols. For example, the first liquid 105 can be a liquid containing 20 ml of alcohol for 1 g of powdered benzo triazole.

[0051] Next, as Figure 3As shown in (a) and (b), the first liquid 105 is dried to form protective layers 105a and 105b, which cover the surface of the substrate 100 on the side where the second layer 103 is provided. The protective layers 105a and 105b can be either solid or in a gel-like state with a viscosity such that they do not flow out from the surface of the substrate 100. The drying of the first liquid 105 can be, for example, natural drying or drying by heating with a heater or the like. Additionally, the substrate 100 can be rotated or a gas such as nitrogen can be supplied for drying.

[0052] At this time, as Figure 3 shown in (a), a film-like protective layer 105a covering the surface of the substrate 100 can be provided. For example, by rotating the substrate 100, a part of the first liquid 105 can be discharged to the outside of the substrate 100 by centrifugal force, and at the same time, the first liquid 105 can be spread to form a film-like protective layer 105a. If a film-like protective layer 105a is formed, it is easy to remove the protective layer 105a described later. Therefore, in the cleaning process and the like described later, it is possible to suppress residues from remaining inside the recess 102a and the like.

[0053] The protective layer 105a has a function of protecting the side walls of the recess 102a and the like from the second liquid 106 described later. Therefore, if the thickness of the protective layer 105a is too thin, the side walls of the recess 102a and the like may be damaged. For example, according to the resistance to the second liquid 106, the thickness of the protective layer 105a can be appropriately set within the range of about several nm to several μm. The thickness of the protective layer 105a can be appropriately determined by conducting experiments and simulations in advance.

[0054] In addition, as Figure 3 shown in (b), the inside of the recess 102a can also be filled with the protective layer 105b. The protective layer 105b has a function of protecting the side walls of the recess 102a and the like from the second liquid 106 described later. Therefore, if the protective layer 105b is filled inside the recess 102a, it is possible to effectively suppress damage to the side walls of the recess 102a and the like.

[0055] For example, when the object to be removed, i.e., the second layer 103, is a metal mask or a resist mask having a deteriorated layer on the surface, it is difficult to remove, so a second liquid 106 with a higher reactivity (for example, a fluorine-containing second liquid 106) is used. If the protective layer 105b is filled inside the recess 102a, it is possible to effectively suppress the second liquid 106 from contacting the side walls of the recess 102a and the like. Therefore, even when using the second liquid 106 with a higher reactivity, it is possible to suppress damage to the side walls of the recess 102a and the like.

[0056] Moreover, in this specification, "embedded" does not only include the case where the entire area inside the recess 102a is filled with the protective layer 105b, but also includes, for example, the case where a part of the inside of the recess 102a is filled with the protective layer 105b and the side walls of the area in the recess 102a that is not filled with the protective layer 105b are covered with the film-like protective layer 105a, etc.

[0057] Next, as shown in Figure 4 (a) and (b), the second liquid 106 is supplied onto the protective layers 105a and 105b. The second liquid 106 can be a liquid that easily reacts with the material of the second layer 103, which is the object to be removed. For example, the second liquid 106 can be a hydrogen peroxide solution, hydrofluoric acid (fluoride acid), an aqueous potassium hydroxide solution, a mixed solution of hydrofluoric acid and nitric acid, an aqueous solution of tetramethylammonium hypochlorite, an aqueous solution of an oxidizing agent having an oxyacid structure, ozone water, etc. However, the second liquid 106 is not limited to the exemplified contents, but any liquid that can dissolve the material of the second layer 103 is acceptable.

[0058] As described above, the protective layers 105a and 105b are formed from the first liquid 105 containing a material that hardly reacts with the second liquid 106. In addition, the protective layers 105a and 105b cover the second layer 103, which is the object to be removed. Therefore, if only the second liquid 106 is supplied, the second layer 103 cannot be removed.

[0059] Then, next, the protective layers 105a and 105b located above the second layer 103 are physically removed. For example, as shown in Figure 5 (a) and (b), the protective layers 105a and 105b located above the second layer 103 can be removed using the removing member 31 described later. The removing member 31 can be, for example, a brush. For example, while rotating the brush and pressing it against the protective layers 105a and 105b located above the second layer 103, and moving the pressed brush in the direction toward the surface of the substrate 100, the protective layers 105a and 105b located above the second layer 103 can be removed. As long as the hair material of the brush has a certain degree of hardness, elasticity, and resistance to the second liquid 106, it is not particularly limited. The hair material can be, for example, nylon or polypropylene, etc. Also, the brush can be moved in the direction toward the surface of the substrate 100 while pressing it against the protective layers 105a and 105b without rotating the brush.

[0060] In addition, the removing member 31 is not limited to a brush, but any member that can physically remove the protective layers 105a and 105b is acceptable. For example, the removing member 31 can also be a sponge brush such as a PVA brush or a brush using a porous material (e.g., fluororesin). Also, as the removing member 31, a brush having both a brush and a sponge brush provided in one brush can be used.

[0061] In addition, when the object to be removed, i.e., the second layer 103, is a resist mask or the like having a deteriorated layer on its surface, at least a part of the deteriorated layer can also be removed by the removing member 31, or scars, holes, etc. can be formed on the deteriorated layer. In this way, it is possible to easily bring the second liquid 106 into contact with the easily removable protective layer located under the deteriorated layer. In addition, since the reactivity of the second liquid 106 can be reduced, damage to the side walls of the concave portion 102a or the like can be suppressed.

[0062] Moreover, when the protective layers 105a and 105b are physically removed, the materials of the protective layers 105a and 105b may adhere to the removing member 31. Therefore, it is preferable to clean the removing member 31 as needed or regularly. For example, the removing member 31 can be cleaned with a solvent, and the removing member 31 cleaned with the solvent can be further cleaned with pure water. The solvent for cleaning the removing member 31 can be, for example, the third liquid 107 described later.

[0063] As Figure 5 As shown in (a) and (b), if the protective layers 105a and 105b located above the second layer 103 are removed, the second liquid 106 comes into contact with the second layer 103. Therefore, the second layer 103 is dissolved (etched) by the second liquid 106. At this time, since the side walls, bottoms of the concave portion 102a, and the third layer 104 are covered by the protective layers 105a and 105b, damage caused by the second liquid 106 coming into contact with these can be suppressed.

[0064] Moreover, if at least a part of the upper surface of the second layer 103 is exposed from the protective layers 105a and 105b, the second layer 103 can be dissolved. However, the larger the exposed area of the second layer 103, the easier it is to dissolve the second layer 103.

[0065] At this time, for example, the end point of the removal operation of the protective layers 105a and 105b can be determined by a preset operation time. For example, the operation time can be appropriately determined in consideration of the materials, thicknesses of the protective layers 105a and 105b located above the second layer 103, and the type, rotation speed, moving speed, number of movements, etc. of the removing member 31. It is only necessary to appropriately determine the end point of the removal operation by conducting experiments and simulations in advance.

[0066] In addition, although the protective layers 105a and 105b have resistance to the second liquid 106, they may sometimes be slightly dissolved by the second liquid 106. For example, if a part of the film-like protective layer 105a is dissolved to form holes or the like, the side walls, bottoms of the concave portion 102a, and the third layer 104 exposed inside the holes may be damaged.

[0067] Based on the knowledge obtained by the present inventors, if the components of the first liquid 105 are added to the second liquid 106, the thinning of the protective layers 105a and 105b can be suppressed. That is, the second liquid 106 can also contain components such as the aforementioned hydrogen peroxide solution and components of the first liquid 105, namely volatile corrosion inhibitors such as benzotriazole. Although the principle of suppressing the thinning of the thickness of the protective layers 105a and 105b is not clear, it can be considered as follows. If the first liquid 105 is added to the second liquid 106, the added first liquid 105 adheres to the protective layers 105a and 105b. Since the adhered first liquid 105 becomes the protective layers 105a and 105b, the thinned portions of the protective layers 105a and 105b are repaired.

[0068] Therefore, depending on the resistance of the protective layers 105a and 105b to the second liquid 106 and the thickness of the protective layers 105a and 105b, etc., the first liquid 105 can be added to the second liquid 106. The addition of the first liquid 105 can be performed, for example, on the surface of the substrate 100. At this time, the first liquid 105 and the second liquid 106 can be supplied simultaneously, or the first liquid 105 and the second liquid 106 can be supplied alternately. In this way, the structure of the supply device can be simplified.

[0069] In addition, the mixed liquid can be supplied to the surface of the substrate 100 after mixing the first liquid 105 and the second liquid 106. For example, the mixed liquid stored in a liquid tank or the like can be supplied to the surface of the substrate 100. For example, the first liquid 105 and the second liquid 106 can be mixed inside a pipe and then supplied to the surface of the substrate 100. If it is made into a mixed liquid, the ratio of the first liquid 105 to the second liquid 106 can be made substantially constant, so that the uneven distribution of the concentration of the second liquid 106 on the surface of the substrate 100 can be suppressed.

[0070] In addition, until the removal of the second layer 103 is completed, the second liquid 106 or the mixed liquid of the first liquid 105 and the second liquid 106 can be continuously supplied. For example, the second liquid 106 or the mixed liquid can be supplied in a so-called running water manner, and in this way, the residues such as the material of the second layer 103 on the surface of the substrate 100 can be suppressed.

[0071] In addition, if the temperature of the second liquid 106 or the temperature of the mixture of the first liquid 105 and the second liquid 106 is increased, the reactivity of the second liquid 106 or the mixture with the second layer 103 can be increased, so that the removal time of the second layer 103 can be shortened. However, if the temperature of the second liquid 106 or the temperature of the mixture is increased, the reactivity of the second liquid 106 or the mixture with the protective layers 105a and 105b is increased, and the thickness of the protective layers 105a and 105b is likely to become thinner. Therefore, the temperature of the second liquid 106 or the temperature of the mixture can be appropriately changed according to the material, thickness, etc. of the protective layers 105a and 105b. The temperature of the second liquid 106 or the temperature of the mixture can be appropriately determined by conducting experiments and simulations in advance. For example, the temperature of the second liquid 106 or the temperature of the mixture can be room temperature (e.g., around 25°C).

[0072] Next, the protective layers 105a and 105b located inside the recess 102a are removed. For example, as Figure 6 shown, by supplying the third liquid 107 to the surface of the substrate 100, the protective layers 105a and 105b are dissolved and removed. As long as the third liquid 107 can dissolve the protective layers 105a and 105b, it is not particularly limited. The third liquid 107 can be, for example, alcohols such as IPA, glycol ethers such as propylene glycol methyl ether acetate (PGMEA), etc.

[0073] In addition, the substrate 100 can be rotated while supplying the third liquid 107. If the substrate 100 is rotated, the dissolved protective layers 105a and 105b and the reacted third liquid 107 can be discharged to the outside of the substrate 100 by centrifugal force, so that the third liquid 107 before the reaction easily contacts the protective layers 105a and 105b. In addition, it is possible to suppress the residue of the material of the protective layers 105a and 105b on the surface of the substrate 100.

[0074] Next, as Figure 7 shown, the fourth liquid 108 is supplied to the surface of the substrate 100 to remove the material of the protective layers 105a and 105b remaining on the surface of the substrate 100 and the third liquid 107. The fourth liquid 108 can be, for example, pure water such as DIW (Deionized water). At this time, the substrate 100 can be rotated while supplying the fourth liquid 108. If the substrate 100 is rotated, the material of the protective layers 105a and 105b remaining on the surface of the substrate 100 and the like can be discharged to the outside of the substrate 100 together with the fourth liquid 108 by centrifugal force. And the treatment (cleaning) with the fourth liquid 108 is not necessarily required and can also be omitted. However, if the treatment with the fourth liquid 108 is performed, the surface of the substrate 100 becomes cleaner.

[0075] Next, the substrate 100 is dried. For example, the substrate 100 is rotated, and the third liquid 107 and the fourth liquid 108 remaining on the surface of the substrate 100 are discharged to the outside of the substrate 100 by centrifugal force. In addition, by rotating the substrate 100, an air flow is brought into contact with the surface of the substrate 100. If the substrate 100 is rotated, the time required for drying can be shortened. Further, a fan or a warm air heater that sends air to the surface of the substrate 100 can be appropriately provided.

[0076] In this way, the second layer 103 can be removed.

[0077] As described above, the substrate processing method according to the present embodiment is a substrate processing method for removing the upper end of the convex portion in the substrate 100 having the concave and convex portions formed on the surface 100a, and includes the following steps.

[0078] A step of supplying the first liquid 105 to the surface 100a of the substrate 100 on which the concave and convex portions are formed.

[0079] A step of forming the protective layers 105a and 105b covering the surface 100a of the substrate 100 from the first liquid 105 supplied to the surface 100a of the substrate.

[0080] A step of supplying the second liquid 106 onto the protective layers 105a and 105b.

[0081] A step of physically removing the protective layers 105a and 105b located at the upper end of the convex portion (the second layer 103) and bringing the second liquid 106 into contact with the upper end of the convex portion from which the protective layers 105a and 105b have been removed.

[0082] According to the substrate processing method according to the present embodiment, when removing the second layer 103 such as an unnecessary hard mask, the side walls and the bottom of the concave portion 102a or the third layer 104 can be protected by the protective layers 105a and 105b. Therefore, damage to the side walls and the bottom of the concave portion 102a or the third layer 104 can be suppressed. That is, according to the substrate processing method according to the present embodiment, in the substrate 100 having the concave and convex portions formed on the surface 100a, the upper end of the convex portion (the second layer 103) can be removed, and damage to the concave portion 102a can be suppressed.

[0083] Substrate processing apparatus

[0084] Next, the substrate processing apparatus 1 according to the present embodiment will be described.

[0085] The substrate processing apparatus 1 can remove the upper end of the convex portion in the substrate 100 having the concave and convex portions formed on the surface 100a.

[0086] Figure 8This is a schematic diagram for illustrating the substrate processing apparatus 1.

[0087] As Figure 8 shown, a placement unit 10, a liquid supply unit 20, a removal unit 30, and a controller 40 can be provided in the substrate processing apparatus 1.

[0088] The placement unit 10 supports the substrate 100 and rotates the supported substrate 100. The placement unit 10 has, for example, a rotating unit 11, a supporting unit 12, and a recovery unit 13.

[0089] The rotating unit 11 has, for example, a base 11a, a shaft 11b, and a driving unit 11c. The base 11a is plate-shaped. The shaft 11b is columnar and is connected to the surface on the side opposite to the side where the supporting unit 12 is provided on the base 11a. For example, the shaft 11b can be integrally formed with the base 11a. The driving unit 11c rotates and stops the rotation of the base 11a via the shaft 11b. In addition, the driving unit 11c can control the rotation speed of the base 11a. The driving unit 11c can include, for example, a control motor such as a servo motor.

[0090] A plurality of supporting units 12 can be provided. The supporting unit 12 has a first part 12a and a second part 12b. The first part 12a is columnar and is provided on the surface on the side opposite to the side where the shaft 11b is provided on the base 11a. The first part 12a is provided near the periphery of the base 11a. The second part 12b is columnar and is provided on the end surface on the side opposite to the base 11a side of the first part 12a. The second part 12b is thinner than the first part 12a. The first part 12a and the second part 12b can be integrally formed.

[0091] When the substrate 100 is placed on the plurality of supporting units 12, the end surface of the first part 12a where the second part 12b is provided contacts the back surface 100b of the substrate 100 (the surface on the side opposite to the side where the second layer 103 is provided). In addition, the side surface of the second part 12b contacts the side surface of the substrate 100 or faces it with a slight gap. If the second part 12b is provided, it is possible to suppress the deviation of the position of the substrate 100 due to centrifugal force.

[0092] The recovery unit 13 has, for example, a cover 13a and a moving unit 13b.

[0093] The cover 13a is cylindrical. Inside the cover 13a, a base 11a, a shaft 11b, and a support portion 12 can be provided. That is, the cover 13a can surround the base 11a. An opening occurs at the end of the cover 13a on the side of the base 11a. A bottom plate can be provided at the end of the cover 13a on the side opposite to the base 11a side. The shaft 11b is penetratively provided inside the hole of the bottom plate. The end of the shaft 11b on the side opposite to the base 11a side is provided outside the cover 13a and is connected to a drive portion 11c. A hole can be provided in the bottom plate of the cover 13a. The hole can be connected to a recovery liquid tank via a pipe. The first liquid 105, the second liquid 106, the third liquid 107, and the fourth liquid 108 supplied to the surface 100a of the substrate 100 and discharged to the outside of the substrate 100 due to centrifugal force are captured by the inner wall of the cover 13a. Since the opening side of the cover 13a is inclined inward, scattering of these liquids to the outside of the cover 13a can be suppressed. These liquids captured by the inner wall of the cover 13a are accommodated inside the cover 13a and sent to the recovery liquid tank via a pipe.

[0094] The moving portion 13b changes the position of the cover 13a in the central axis direction of the rotating portion 11. The moving portion 13b can include, for example, a cylinder or the like. For example, when placing the substrate 100 on the support portion 12 or taking out the substrate 100 from the support portion 12, as Figure 8 shown, the position of the cover 13a is lowered by the moving portion 13b so that the support portion 12 is located near the opening of the cover 13a. In this way, the transfer of the substrate 100 becomes easy. On the other hand, when supplying liquids such as the first liquid 105 to the surface 100a of the substrate 100, the position of the cover 13a is raised by the moving portion 13b so that the substrate 100 is located inside the cover 13a. In this way, it is easy to capture the liquids discharged to the outside of the substrate 100.

[0095] The liquid supply portion 20 includes, for example, a first supply portion 21, a second supply portion 22, a third supply portion 23, and a fourth supply portion 24.

[0096] The first supply portion 21 supplies the first liquid 105 to the surface 100a of the substrate 100 on which the uneven portion is formed.

[0097] The first supply portion 21 includes, for example, a nozzle 21a, a liquid tank 21b, a pump 21c, and a control valve 21d.

[0098] The nozzle 21a is cylindrical, and the end of the opening side faces the vicinity of the center of the surface 100a of the substrate 100. The nozzle 21a can either directly discharge the first liquid 105 or be a spray nozzle that sprays the first liquid 105 after atomizing it. The first liquid 105 supplied to the vicinity of the center of the surface 100a of the substrate 100 spreads on the surface 100a of the substrate 100 due to the centrifugal force caused by the rotation of the substrate 100.

[0099] The liquid tank 21b accommodates the first liquid 105.

[0100] The pump 21c is disposed between the nozzle 21a and the liquid tank 21b, and supplies the first liquid 105 accommodated in the liquid tank 21b to the nozzle 21a.

[0101] The control valve 21d is disposed between the pump 21c and the nozzle 21a, and switches the supply and the stop of the supply of the first liquid 105. In addition, the control valve 21d can also control the flow rate, pressure, etc. of the first liquid 105.

[0102] The second supply unit 22 supplies the second liquid 106 onto the protective layers 105a and 105b, and the protective layers 105a and 105b are formed by the first liquid 105 supplied to the surface 100a of the substrate 100 and cover the surface 100a of the substrate 100.

[0103] The first supply unit 22 has, for example, a nozzle 21a, a liquid tank 22b, a pump 22c, and a control valve 22d. And although the case where the nozzle 21a for supplying the first liquid 105 is also used for supplying the second liquid 106 is illustrated, a nozzle dedicated only to the supply of the second liquid 106 can also be provided separately. The second liquid 106 supplied near the center of the surface 100a of the substrate 100 spreads on the surface 100a of the substrate 100 due to the centrifugal force caused by the rotation of the substrate 100.

[0104] The liquid tank 22b accommodates the second liquid 106.

[0105] The pump 22c is disposed between the nozzle 21a and the liquid tank 22b, and supplies the second liquid 106 accommodated in the liquid tank 22b to the nozzle 21a.

[0106] The control valve 22d is disposed between the pump 22c and the nozzle 21a, and switches the supply and the stop of the supply of the second liquid 106. In addition, the control valve 22d can also control the flow rate, pressure, etc. of the second liquid 106.

[0107] The third supply unit 23 supplies the third liquid 107 to the surface 100a of the substrate 100. The third supply unit 23 has, for example, a nozzle 23a, a liquid tank 23b, a pump 23c, and a control valve 23d.

[0108] The nozzle 23a is cylindrical, and the end on the opening side faces near the center of the surface 100a of the substrate 100. The nozzle 23a can either directly discharge the third liquid 107 or be a spray nozzle that sprays the third liquid 107 in a mist form. The third liquid 107 supplied near the center of the surface 100a of the substrate 100 spreads on the surface 100a of the substrate 100 due to the centrifugal force caused by the rotation of the substrate 100.

[0109] The liquid tank 23b accommodates the third liquid 107.

[0110] The pump 23c is disposed between the nozzle 23a and the liquid tank 23b, and supplies the third liquid 107 accommodated in the liquid tank 23b to the nozzle 23a.

[0111] The control valve 23d is disposed between the pump 23c and the nozzle 23a, and switches the supply and the supply stop of the third liquid 107. In addition, the control valve 23d can also control the flow rate, pressure, etc. of the third liquid 107.

[0112] The fourth supply unit 24 supplies the fourth liquid 108 to the surface 100a of the substrate 100. The fourth supply unit 24 includes, for example, a nozzle 24a, a liquid tank 24b, a pump 24c, and a control valve 24d.

[0113] The nozzle 24a has a cylindrical shape, and the end portion on the opening side faces the vicinity of the center of the surface 100a of the substrate 100. The nozzle 24a can directly discharge the fourth liquid 108, or can be a spray nozzle that atomizes the fourth liquid 108 and then sprays it. The fourth liquid 108 supplied to the vicinity of the center of the surface 100a of the substrate 100 spreads on the surface 100a of the substrate 100 due to the centrifugal force caused by the rotation of the substrate 100.

[0114] The liquid tank 24b accommodates the fourth liquid 108.

[0115] The pump 24c is disposed between the nozzle 24a and the liquid tank 24b, and supplies the fourth liquid 108 accommodated in the liquid tank 24b to the nozzle 24a.

[0116] The control valve 24d is disposed between the pump 24c and the nozzle 24a, and switches the supply and the supply stop of the fourth liquid 108. In addition, the control valve 24d can also control the flow rate, pressure, etc. of the fourth liquid 108.

[0117] Moreover, the nozzles 21a, 23a, and 24a can be used in common. For example, the supply of the first liquid 105, the second liquid 106, the third liquid 107, and the fourth liquid 108 can be switched, and these liquids can be sequentially supplied from one nozzle.

[0118] In addition, the nozzles 21a, 23a, and 24a can be mounted on a rotating arm 25 or the like to change the positions of the nozzles 21a, 23a, and 24a. For example, when supplying the first liquid 105 to the fourth liquid 108 to the surface 100a of the substrate 100, the rotating arm 25 can position the nozzles 21a, 23a, and 24a above the central region of the surface 100a of the substrate 100. When transferring the substrate 100 to the support portion 12, the rotating arm 25 can retract the nozzles 21a, 23a, and 24a to the outside of the cover 13a. For example, the rotating arm 25 can be driven by a control motor such as a cylinder or a servo motor.

[0119] The removing unit 30 physically removes the protective layers 105a and 105b located at the upper ends of the convex portions (second layer 103), and causes the second liquid 106 to contact the upper ends of the convex portions (second layer 103) from which the protective layers 105a and 105b have been removed.

[0120] The removing unit 30 includes, for example, a removing member 31, a driving unit 32, a cleaning unit 33, and a cleaning unit 34.

[0121] The removing member 31 can contact the protective layer 100a located at the upper end of the convex portion (second layer 103). As described above, the removing member 31 can be, for example, a brush or the like. And since the removing member 31 can be made as described above, detailed description thereof is omitted.

[0122] The driving unit 32 can perform at least any one of rotation of the removing member 31 and movement of the removing member 31. For example, the driving unit 32 rotates the removing member 31. In addition, for example, the driving unit 32 moves the removing member 31 in a direction perpendicular to the surface 100a of the substrate 100. In addition, for example, the driving unit 32 moves the removing member 31 in a direction along the surface 100a of the substrate 100. For example, the driving unit 32 can press the brush against the protective layer 100a located at the upper end of the convex portion (second layer 103), and at the same time can move the brush in a direction along the surface 100a of the substrate 100. At this time, the driving unit 32 can also rotate the brush. The driving unit 32 may include, for example, a control motor such as a servo motor, a cylinder, a guiding mechanism, and the like.

[0123] The cleaning unit 33 includes, for example, a liquid tank 33a and a cleaning liquid 33b.

[0124] The liquid tank 33a may have an opening at its upper end. The cleaning liquid 33b is stored in the liquid tank 33a.

[0125] The cleaning liquid 33b can be a solvent that can dissolve materials such as the protective layers 105a and 105b attached to the removing member 31. The cleaning liquid 33b can be, for example, the third liquid 107.

[0126] Since the upper end of the liquid tank 33a has an opening, the driving unit 32 can move the removing member 31 from the surface 100a of the substrate 100 into the cleaning liquid 33b. In this way, the removing member 31 can be cleaned by the cleaning liquid 33b. In addition, the driving unit 32 can rotate the removing member 31 immersed in the cleaning liquid 33b, or change the rotation speed, or alternately reverse the rotation direction. In this way, the cleaning effect of the removing member 31 can be improved.

[0127] The cleaning unit 34 includes, for example, a liquid tank 34a and a cleaning liquid 34b.

[0128] The liquid tank 34a may have an opening at its upper end. The cleaning liquid 34b is stored in the liquid tank 34a.

[0129] The cleaning liquid 34b can be, for example, pure water or the like. The cleaning liquid 34b can also be, for example, the fourth liquid 108.

[0130] Since the upper end of the liquid tank 34a is open, the driving unit 32 can move the removing member 31 from the surface 100a of the substrate 100 into the cleaning liquid 34b. In this way, the removing member 31 can be cleaned by the cleaning liquid 34b. In addition, the driving unit 32 can rotate the removing member 31 immersed in the cleaning liquid 34b, change the rotation speed, or alternately reverse the rotation direction. In this way, the cleaning effect of the removing member 31 can be improved.

[0131] Moreover, depending on the material adhering to the removing member 31, the composition of the liquid, the adhesion amount, etc., it may sometimes be sufficient to clean with either the cleaning liquid 33b or the cleaning liquid 34b. Therefore, at least either the cleaning unit 33 or the cleaning unit 34 can also be provided.

[0132] That is, the substrate processing apparatus 1 can also include liquid tanks 33a and 34a that store the cleaning liquids 33b and 34b. The driving unit 32 can move the removing member 31 into the liquid tanks 33a and 34a, and immerse the removing member 31 in the cleaning liquids 33b and 34b.

[0133] The controller 40 can have, for example, an arithmetic unit such as a CPU (Central Processing Unit) and a storage unit such as a memory. The controller 40 can be, for example, a computer or the like. The controller 40 controls the operations of the respective elements provided in the substrate processing apparatus 1 according to a control program stored in the storage unit.

[0134] The controller 40 can execute the aforementioned substrate processing method according to a control program stored in the storage unit.

[0135] For example, the controller 40 controls the driving unit 11c to rotate the substrate 100, and controls the first supply unit 21 (the pump 21c and the control valve 21d) to supply the first liquid 105 to the surface 100a of the substrate 100 having the concavo-convex portions.

[0136] For example, after supplying the first liquid 105, the controller 40 controls the driving unit 11c to rotate the substrate 100, thereby drying the first liquid 105, and forming the protective layers 105a and 105b that cover the surface 100a of the substrate 100.

[0137] For example, the controller 40 controls the second supply unit 22 (the pump 22c and the control valve 22d) to supply the second liquid 106 onto the protective layers 105a and 105b, and the protective layers 105a and 105b are formed by the first liquid 105 supplied to the surface 100a of the substrate 100 and cover the surface 100a of the substrate 100.

[0138] At this time, the controller 40 can also control the first supply unit 21 (pump 21c, control valve 21d) and the second supply unit 22 (pump 22c, control valve 22d) to supply the first liquid 105 and the second liquid 106 to the surface 100a of the substrate 100 on which the protective layers 105a and 105b are formed. At this time, the first liquid 105 and the second liquid 106 can be mixed inside the pipe or nozzle, and the mixed liquid can be supplied to the surface 100a of the substrate 100. In addition, the first liquid 105 and the second liquid 106 can be alternately supplied to the surface 100a of the substrate 100 to generate a mixed liquid on the surface 100a of the substrate 100. Further, the mixed liquid can be stored in the liquid tank 22b, and the mixed liquid can be supplied instead of the second liquid 106.

[0139] For example, the controller 40 controls the removing unit 30 (driving unit 32) to physically remove the protective layers 105a and 105b located at the upper ends of the convex portions (the second layer 103), and causes the second liquid 106 to contact the upper ends of the convex portions (the second layer 103) from which the protective layer 105a has been removed. If the second liquid 106 comes into contact with the second layer 103, the second layer 103 is dissolved (etched) by the second liquid 106.

[0140] For example, the controller 40 controls the third supply unit 23 (pump 23c, control valve 23d) to supply the third liquid 107 to the surface 100a of the substrate 100 from which the second layer 103 has been removed. The protective layers 105a and 105b located inside the concave portion 102a are removed by the third liquid 107. The controller 40 can control the driving unit 11c to rotate the substrate 100, and discharge the dissolved protective layers 105a and 105b and the third liquid 107 whose reaction has ended to the outside of the substrate 100 by centrifugal force.

[0141] For example, the controller 40 controls the fourth supply unit 24 (pump 24c, control valve 24d) to supply the fourth liquid 108 to the surface 100a of the substrate 100 that has been treated with the third liquid 107. The surface 100a of the substrate 100 is cleaned with the fourth liquid 108. At this time, the controller 40 can control the driving unit 11c to rotate the substrate 100, and the fourth liquid 108 can be discharged to the outside of the substrate 100 by centrifugal force.

[0142] For example, the controller 40 controls the driving unit 11c to rotate the substrate 100 to dry the surface 100a of the substrate 100 that has been cleaned with the fourth liquid 108.

[0143] For example, the controller 40 can control the removing unit 30 (driving unit 32) to immerse the removing member 31 in the cleaning liquids 33b and 34b. By immersing the removing member 31 in the cleaning liquids 33b and 34b, materials such as those adhering to the protective layers 105a and 105b of the removing member 31 can be removed. At this time, the controller 40 can control the removing unit 30 (driving unit 32) to rotate the removing member 31 immersed in the cleaning liquids 33b and 34b, change the rotational speed, or alternately reverse the rotational direction. In this way, the cleaning effect of the removing member 31 can be improved.

[0144] In addition, the controller 40 controls the first supply unit 21, the second supply unit 22, the third supply unit 23, and the fourth supply unit 24 to supply the first liquid 105, the second liquid 106, the third liquid 107, and the fourth liquid 108 to the surface 100a of the substrate 100. At this time, the controller 40 can control the driving unit 11c to rotate the substrate 100 at a rotational speed corresponding to each liquid (the first liquid 105, the second liquid 106, the third liquid 107, and the fourth liquid 108). During the period from the stop of the supply of this liquid to the start of the supply of the next liquid, the rotation of the substrate 100 can also be switched to the rotational speed corresponding to the next supplied liquid. In addition, when changing the supplied liquid, the substrate 100 can also be stopped from rotating. In addition, during the supply of liquid from one supply unit, the rotational speed of the substrate 100 can either be maintained constant or the rotational speed can be switched. Of course, rotation is not necessarily required, and the substrate 100 can also be made not to rotate, but only the liquid can be supplied.

[0145] Moreover, since the processing sequence, the liquids used, the effects, etc. of the substrate 100 can be made the same as those described above, detailed descriptions are omitted.

[0146] The embodiments have been illustrated above. However, the present invention is not limited to these descriptions.

[0147] Regarding the foregoing embodiments, as long as they have the features of the present invention, inventions in which those skilled in the art appropriately add, omit, or change conditions in the processes, or inventions in which components are added, removed, or design-changed are also included in the scope of the present invention.

[0148] In addition, as long as it is technically feasible, the elements included in the foregoing embodiments can be combined. As long as the technology after such combination includes the features of the present invention, it is also included in the scope of the present invention.

Claims

1. A substrate processing method for removing the upper ends of convex portions in a substrate having convex and concave portions formed on its surface, characterized in that: It includes: a step of supplying a first liquid containing a volatile corrosion inhibitor to the surface of the substrate having convex and concave portions formed thereon; A step of forming a protective layer covering the surface of the substrate from the first liquid supplied to the surface of the substrate; A step of supplying a second liquid onto the protective layer; And a step of physically removing the protective layer located at the upper ends of the convex portions to bring the second liquid into contact with the upper ends of the convex portions from which the protective layer has been removed.

2. The substrate processing method according to claim 1, characterized in that: The upper ends of the convex portions are layers containing at least any one of a metal and a metal oxide, The metal oxide is an oxide of the metal.

3. The substrate processing method according to claim 1 or 2, characterized in that, The second liquid contains at least any one of a hydrogen peroxide solution, hydrofluoric acid, an aqueous potassium hydroxide solution, a mixed solution of hydrofluoric acid and nitric acid, an aqueous solution of tetramethylammonium hypochlorite, an aqueous solution of an oxidizing agent having an oxyacid structure, and ozone water.

4. The substrate processing method according to claim 3, characterized in that, The second liquid further contains a volatile corrosion inhibitor.

5. A substrate processing apparatus for removing the upper ends of convex portions in a substrate having convex and concave portions formed on its surface, characterized in that: It includes: a first supply unit capable of supplying a first liquid containing a volatile corrosion inhibitor to the surface of the substrate having convex and concave portions formed thereon; A second supply unit capable of supplying a second liquid onto a protective layer formed from the first liquid supplied to the surface of the substrate and covering the surface of the substrate; And a removal unit that physically removes the protective layer located at the upper ends of the convex portions to enable the second liquid to contact the upper ends of the convex portions from which the protective layer has been removed.

6. The substrate processing apparatus according to claim 5, characterized in that: The removal unit includes: a removal member that can contact the protective layer located at the upper ends of the convex portions; And a drive unit capable of performing at least any one of rotation of the removal member and movement of the removal member.

7. The substrate processing apparatus according to claim 6, characterized in that: The removal member is a brush, The drive unit can press the brush against the protective layer located at the upper ends of the convex portions and can move the brush in a direction along the surface of the substrate at the same time.

8. The substrate processing apparatus according to claim 7, wherein The drive unit can also rotate the brush.

9. The substrate processing apparatus according to any one of claims 6 to 8, characterized in that: It further includes a liquid tank capable of accommodating a cleaning liquid, The drive unit can move the removal member into the interior of the liquid tank to immerse the removal member in the cleaning liquid.

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