Substrate processing method, substrate processing device, method for producing semiconductor device, and semiconductor production device

Abstract

The present invention provides: a substrate processing method with which it is possible to form a self-assembled monolayer film on a substrate surface efficiently and in a short time, the self-assembled monolayer film having exceptional density and protection performance due to suppression or reduction in the occurrence of film defects; a substrate processing device; a method for producing a semiconductor device; and a semiconductor production device. A substrate processing method according to the present invention includes forming a SAM on a surface Wf of a substrate W, wherein: the substrate processing method includes a surface modification step S102 for applying hydroxyl groups to the surface Wf of the substrate W to perform surface modification, and a film formation step S104 for bringing a treatment liquid containing SAM molecules capable of forming a SAM into contact with the surface Wf of the substrate W after the surface modification step S102 and thereby forming a SAM; the molecules have hydroxyl groups; and the film formation step S104 includes chemically adsorbing the SAM molecules to the surface Wf of the substrate W using a dehydration condensation reaction between the hydroxyl groups applied to the surface Wf of the substrate W and the hydroxyl groups included in the SAM molecules, thereby forming a SAM.

Description

Substrate processing method, substrate processing apparatus, semiconductor device manufacturing method, and semiconductor manufacturing apparatus

[0001] The present invention relates to a substrate processing method and apparatus capable of efficiently forming a self-assembled monolayer having excellent density and protective performance in a short time, as well as a semiconductor device manufacturing method and semiconductor manufacturing apparatus.

[0002] In the manufacture of semiconductor devices, photolithography is widely used as a technique for selectively forming a film on a specific surface region of a substrate. For example, after forming a lower layer wiring, an insulating film is formed, and then a dual damascene structure having trenches and via holes is formed by photolithography and etching, and a conductive film such as Cu is filled in the trenches and via holes to form wiring.

[0003] However, in recent years, as semiconductor devices have become increasingly miniaturized, the alignment accuracy of photolithography has become insufficient, and therefore there is a demand for an alternative method to photolithography that can selectively form films in specific regions on the substrate surface with high precision.

[0004] For example, Patent Document 1 discloses a method for manufacturing a silicon nitride (SiN) film and a silicon oxide (SiO ２ In a substrate having a silicon nitride film and a silicon dioxide film formed in the surface thereof, a method is disclosed in which a hot phosphoric acid resistant material is formed as a SAM in advance on the surface of the silicon dioxide film in order to selectively etch the silicon nitride film.

[0005] In order to adequately protect the silicon oxide film from the etching solution, it is necessary to form a highly dense SAM. However, with conventional SAM formation methods, it is difficult to form such a highly dense SAM in a short time, resulting in poor production efficiency.

[0006] Japanese Patent No. 5490071

[0007] The present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a substrate processing method and substrate processing apparatus, as well as a semiconductor device manufacturing method and semiconductor manufacturing apparatus, that are capable of efficiently depositing a self-assembled monolayer having excellent density and protective performance on a substrate surface in a short time by suppressing or reducing the occurrence of film defects.

[0008] In order to solve the above-mentioned problems, the substrate processing method of the present invention is a substrate processing method for forming a self-assembled monolayer on a surface of a substrate, comprising: a surface modification step of modifying the surface of the substrate by adding hydroxyl groups to the surface of the substrate; and a film formation step of contacting the surface of the substrate after the surface modification step with a processing liquid containing molecules capable of forming the self-assembled monolayer to form the self-assembled monolayer, wherein the molecules have functional groups capable of undergoing a dehydration condensation reaction with the hydroxyl groups, and the film formation step is a step of chemically adsorbing the molecules to the surface of the substrate by a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

[0009] In the film formation process of the above-described configuration, molecules capable of forming a self-assembled monolayer (hereinafter sometimes referred to as "SAM") (hereinafter sometimes referred to as "SAM molecules") are chemically adsorbed onto the surface of a substrate, thereby forming a SAM. Here, the SAM formed in the film formation process may have film defects due to localized inability of the SAM molecules to chemically adsorb to the substrate surface. In particular, if the contact time of the SAM molecules with the substrate surface is short, the frequency of in-plane film defects increases, or the area of ​​the film defects increases. However, in the above-described configuration, a surface modification process is performed to add hydroxyl groups to the substrate surface before the film formation process. Therefore, when SAM molecules having functional groups capable of dehydration condensation with hydroxyl groups come into contact with the substrate surface, a dehydration condensation reaction occurs between the functional groups of the SAM molecules and the hydroxyl groups on the substrate surface, allowing the SAM molecules to chemically adsorb to the substrate surface at a high density. As a result, unlike conventional substrate processing methods, the formation of dense SAMs does not require the SAM molecules to be in contact with the substrate surface for a long period of time, and the occurrence of film defects can be suppressed, and a SAM with excellent density and protective performance can be efficiently formed in a short period of time.

[0010] In the above-described configuration, the surface modification step may be a step of contacting the surface of the substrate with a surface modification liquid made of an alkaline solution. By contacting the surface of the substrate with the alkaline solution, more hydroxyl groups can be imparted to the surface of the substrate. As a result, more SAM molecules can be chemically adsorbed to the surface of the substrate, and a SAM with excellent density and protective performance can be formed.

[0011] Furthermore, in the above-mentioned configuration, the alkaline solution is preferably an ammonia-hydrogen peroxide solution mixture, ammonia water, a tetramethylammonium hydroxide aqueous solution, or a trimethyl-2-hydroxyethylammonium hydroxide aqueous solution.

[0012] In the above-described configuration, the surface modification step may be a step of irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms. This allows more hydroxyl groups to be added to the surface of the substrate. As a result, more SAM molecules can be chemically adsorbed onto the surface of the substrate, forming a SAM with excellent density and protective performance.

[0013] Furthermore, the above-described method preferably further includes a pretreatment step of contacting the surface of the substrate with a pretreatment solution containing hydrogen fluoride prior to the surface modification step. This allows for the introduction of hydroxyl groups in the surface modification step to be performed effectively. As a result, SAM molecules can be chemically adsorbed to the surface of the substrate at a higher density, resulting in the formation of a SAM with even greater density and protective performance.

[0014] In order to solve the above-mentioned problems, the present invention provides a method for manufacturing a semiconductor device, which includes processing a substrate having a laminate provided on its surface, wherein the laminate includes an alternating stack of a protected layer to be protected during etching and a layer to be etched to be etched, and the method includes the steps of selectively forming a self-assembled monolayer on at least the surface of the protected layer, and selectively etching the layer to be etched using the self-assembled monolayer as a protective layer, wherein the step of forming the self-assembled monolayer includes a surface modification step of modifying the surface of the protected layer by adding hydroxyl groups to the surface of the protected layer, and a film formation step of contacting the surface of the protected layer after the surface modification step with a treatment liquid containing molecules capable of forming the self-assembled monolayer to form the self-assembled monolayer, wherein the molecules have functional groups capable of undergoing a dehydration condensation reaction with the hydroxyl groups, and the film formation step is a step of chemically adsorbing the molecules to the surface of the protected layer through a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

[0015] In the film formation process of the above-described configuration, SAM molecules are chemically adsorbed onto the surface of the protected layer and self-assembled to form a SAM. However, in the SAM formed in the film formation process, film defects may occur due to the SAM molecules being unable to chemically adsorb locally to the surface of the protected layer. In particular, if the contact time of the SAM molecules with the surface of the protected layer is short, the frequency of in-plane film defects increases or the area of ​​the film defects increases. However, in the above-described configuration, a surface modification process is performed before the film formation process to impart hydroxyl groups to the surface of the protected layer. Therefore, when SAM molecules having functional groups capable of dehydration condensation with hydroxyl groups come into contact with the surface of the protected layer, a dehydration condensation reaction occurs between the functional groups of the SAM molecules and the hydroxyl groups on the surface of the protected layer, allowing the SAM molecules to be chemically adsorbed to the surface of the protected layer at a high density. As a result, unlike conventional semiconductor device manufacturing methods, the formation of a dense SAM does not require the SAM molecules to be in contact with the surface of the layer to be protected for a long period of time, and a SAM with excellent density and protective performance can be efficiently formed in a short period of time while suppressing the occurrence of film defects.

[0016] In the above-described configuration, the surface modification step may be a step of contacting the surface of the layer to be protected with a surface modification liquid made of an alkaline solution. By contacting the surface of the layer to be protected with the alkaline solution, more hydroxyl groups can be imparted to the surface of the layer to be protected. As a result, more SAM molecules can be chemically adsorbed to the surface of the layer to be protected, and a SAM with excellent density and protective performance can be formed.

[0017] Furthermore, in the above-mentioned configuration, the alkaline solution is preferably an ammonia-hydrogen peroxide solution mixture, ammonia water, a tetramethylammonium hydroxide aqueous solution, or a trimethyl-2-hydroxyethylammonium hydroxide aqueous solution.

[0018] In the above-described configuration, the surface modification step may be a step of irradiating the surface of the layer to be protected with ultraviolet light in an atmosphere containing oxygen atoms. This allows more hydroxyl groups to be added to the surface of the layer to be protected. As a result, more SAM molecules can be chemically adsorbed onto the surface of the layer to be protected, forming a SAM with excellent density and protective performance.

[0019] Furthermore, the above-described configuration preferably further includes a pretreatment step of contacting the surface of the layer to be protected with a pretreatment liquid containing hydrogen fluoride prior to the surface modification step. This allows for the introduction of hydroxyl groups in the surface modification step to be performed effectively. As a result, SAM molecules can be chemically adsorbed to the surface of the layer to be protected with even higher density, resulting in the formation of a SAM with even greater density and protective performance.

[0020] In order to solve the above-mentioned problems, the substrate processing apparatus of the present invention is a substrate processing apparatus that forms a self-assembled monolayer on the surface of a substrate, and is characterized in that it includes a surface modification unit that modifies the surface of the substrate by adding hydroxyl groups to the surface of the substrate, and a processing liquid supply unit that forms the self-assembled monolayer by supplying a processing liquid containing molecules capable of forming the self-assembled monolayer to the surface of the substrate that has been surface-modified by the surface modification unit, the molecules having functional groups that can undergo a dehydration condensation reaction with the hydroxyl groups, and the processing liquid supply unit chemically adsorbs the molecules to the surface of the substrate by a dehydration condensation reaction between the hydroxyl groups and the functional groups possessed by the molecules.

[0021] According to the above-described configuration, the surface modification unit modifies the substrate surface by adding hydroxyl groups to the surface. The processing solution supply unit forms a SAM by contacting the substrate surface with a processing solution containing SAM molecules. Since the SAM molecules have functional groups capable of undergoing a dehydration condensation reaction with hydroxyl groups, when the SAM molecules contact the substrate surface, a dehydration condensation reaction occurs between the functional groups of the SAM molecules and the hydroxyl groups on the substrate surface, allowing the SAM molecules to chemisorb to the substrate surface. Furthermore, the chemisorbed SAM molecules self-assemble, thereby forming a SAM. In the SAM formed on the substrate surface, film defects may occur due to localized inability of the SAM molecules to chemisorb to the substrate surface. In particular, if the contact time of the SAM molecules with the substrate surface is short, the frequency of film defects within the surface may increase or the area of ​​the film defects may become larger. However, the above-described configuration further includes a surface modification unit that modifies the substrate surface before forming the SAM. More specifically, the apparatus includes a surface modification unit that provides hydroxyl groups to the surface of the substrate, thereby reducing the area where SAM molecules cannot chemically adsorb, and suppressing the occurrence of film defects without requiring the SAM molecules to be in contact with the substrate surface for a long period of time to form a dense SAM, as is the case with conventional substrate processing apparatuses, thereby enabling a SAM with excellent density and protective performance to be efficiently formed in a short period of time.

[0022] In the above configuration, the surface modification unit may be a surface modification liquid supply unit that supplies a surface modification liquid composed of an alkaline solution to the surface of the substrate. By supplying the surface modification liquid composed of an alkaline solution to the substrate surface, the surface of the substrate can be provided with hydroxyl groups. This minimizes the areas where SAM molecules cannot be chemically adsorbed, allowing more SAM molecules to be chemically adsorbed to the substrate surface at a high density. As a result, a SAM with excellent density and protective performance can be formed.

[0023] Furthermore, in the above-mentioned configuration, the alkaline solution is preferably an ammonia-hydrogen peroxide solution mixture, ammonia water, a tetramethylammonium hydroxide aqueous solution, or a trimethyl-2-hydroxyethylammonium hydroxide aqueous solution.

[0024] In the above configuration, the surface modification unit may be an ultraviolet irradiation unit that irradiates the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms. By irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms, the ultraviolet irradiation unit can impart hydroxyl groups to the surface of the substrate. This minimizes the areas where SAM molecules cannot chemisorb, allowing more SAM molecules to chemisorb to the surface of the substrate at high density. As a result, a SAM with excellent density and protective performance can be formed.

[0025] Furthermore, the above-described configuration preferably further includes a pretreatment liquid supply unit that supplies a pretreatment liquid containing hydrogen fluoride to the surface of the substrate before the surface is modified by the surface modification unit. By supplying a pretreatment liquid containing hydrogen fluoride to the substrate surface before the surface modification is performed by the pretreatment liquid supply unit, hydroxyl groups can be effectively introduced when the surface is modified by the surface modification unit. As a result, SAM molecules can be chemically adsorbed to the substrate surface at an even higher density, resulting in the formation of a SAM with even greater density and protective performance.

[0026] In order to solve the above-mentioned problems, the semiconductor manufacturing apparatus of the present invention is a semiconductor manufacturing apparatus that processes a substrate having a laminate provided on its surface, wherein the laminate includes an alternating stack of a protected layer that is to be protected by etching and a etched layer that is to be etched, and includes: a surface modification unit that modifies the surface of the protected layer by adding hydroxyl groups; a processing liquid supply unit that forms the self-assembled monolayer by supplying a processing liquid containing molecules capable of forming a self-assembled monolayer to the surface of the protected layer that has been surface-modified by the surface modification unit; and an etching unit that selectively etches and removes the etched layer using the self-assembled monolayer as a protective layer, wherein the molecules have functional groups that can undergo a dehydration condensation reaction with the hydroxyl groups, and the processing liquid supply unit chemically adsorbs the molecules to the surface of the protected layer by a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

[0027] The semiconductor manufacturing apparatus having the above configuration enables highly selective etching of the layer to be etched by forming a SAM on at least the surface of the layer to be protected before etching the layer to be etched. In the above configuration, the surface modification unit modifies the surface of the layer to be protected by adding hydroxyl groups to the surface of the layer to be protected. The processing solution supply unit forms a SAM by contacting the surface of the layer to be protected with a processing solution containing SAM molecules. Since the SAM molecules have functional groups capable of dehydration condensation with hydroxyl groups, when the SAM molecules contact the surface of the layer to be protected, a dehydration condensation reaction occurs between the functional groups of the SAM molecules and the hydroxyl groups on the surface of the layer to be protected, allowing the SAM molecules to chemisorb. Furthermore, the chemisorbed SAM molecules self-assemble, thereby forming a SAM. The SAM formed on the surface of the layer to be protected may have film defects due to localized inability of the SAM molecules to chemisorb to the surface of the layer to be protected. In particular, when the contact time of the SAM molecules with the surface of the layer to be protected is short, the frequency of film defects within the surface increases and the area of ​​the film defects becomes large. However, the above-mentioned configuration further includes a surface modification unit that performs surface modification on the surface of the layer to be protected before forming the SAM. More specifically, the configuration includes a surface modification unit that imparts hydroxyl groups to the surface of the layer to be protected. This reduces the area where the SAM molecules cannot chemically adsorb, and suppresses the occurrence of film defects, allowing for the efficient formation of a SAM with excellent density and protective performance in a short time, without requiring the SAM molecules to be in contact with the surface of the layer to be protected for a long period of time, as is the case with conventional semiconductor manufacturing equipment, in order to form a dense SAM.

[0028] In order to solve the above-mentioned problems, the semiconductor manufacturing apparatus of the present invention is a semiconductor manufacturing apparatus that processes a substrate having a laminate provided on its surface, wherein the laminate includes an alternating stack of a protected layer that is to be protected by etching and a etched layer that is to be etched, and includes a substrate processing unit that selectively forms a self-assembled monolayer on at least the surface of the protected layer, and an etching processing unit that selectively etches and removes the etched layer using the self-assembled monolayer as a protective layer, wherein the substrate processing unit includes a surface modification section that performs surface modification by adding hydroxyl groups to the surface of the protected layer, and a processing liquid supply section that forms the self-assembled monolayer on the surface of the protected layer that has been surface-modified by the surface modification section, wherein the molecules have functional groups that can undergo a dehydration condensation reaction with the hydroxyl groups, and the processing liquid supply section chemically adsorbs the molecules to the surface of the protected layer through a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

[0029] The semiconductor manufacturing apparatus of the above configuration includes at least a substrate processing unit that selectively forms a SAM on a layer to be protected and an etching processing unit that selectively etches and removes the layer to be etched. Prior to etching the layer to be etched in the etching processing unit, the substrate processing unit forms a SAM on at least the surface of the layer to be protected to protect it, thereby enabling highly selective etching of the layer to be etched. In the above configuration, the surface modification unit modifies the surface of the layer to be protected by adding hydroxyl groups to the surface of the layer to modify the surface. Furthermore, the processing solution supply unit forms a SAM by contacting the surface of the layer to be protected with a processing solution containing SAM molecules. Here, the SAM molecules have functional groups capable of dehydration condensation reactions with hydroxyl groups. Therefore, when the SAM molecules contact the surface of the layer to be protected, a dehydration condensation reaction occurs between the functional groups of the SAM molecules and the hydroxyl groups on the surface of the layer to chemically adsorb the SAM molecules. Furthermore, the chemically adsorbed SAM molecules self-assemble, thereby forming a SAM. Here, in the SAM formed on the surface of the protected layer, film defects may occur due to the inability of SAM molecules to chemically adsorb locally to the surface of the protected layer. In particular, if the contact time of the SAM molecules with the surface of the protected layer is short, the frequency of in-plane film defects increases or the area of ​​film defects becomes large. However, the above-described configuration further includes a surface modification unit that performs surface modification on the surface of the protected layer before forming the SAM. More specifically, the configuration includes a surface modification unit that imparts hydroxyl groups to the surface of the protected layer. This reduces the area where SAM molecules cannot chemically adsorb. Unlike conventional semiconductor manufacturing equipment, this configuration does not require long contact times of SAM molecules with the surface of the protected layer to form a dense SAM. This suppresses the occurrence of film defects and enables the efficient formation of a SAM with excellent density and protective performance in a short time.

[0030] In the above configuration, the surface modification unit may be a surface modification liquid supply unit that supplies a surface modification liquid composed of an alkaline solution to the surface of the layer to be protected. By supplying the surface modification liquid composed of an alkaline solution to the surface of the layer to be protected, the surface of the layer to be protected can be provided with hydroxyl groups. This minimizes the area where SAM molecules cannot be chemically adsorbed, allowing more SAM molecules to be chemically adsorbed to the surface of the layer to be protected at a high density. As a result, a SAM with excellent density and protective performance can be formed.

[0031] Furthermore, in the above-mentioned configuration, the alkaline solution is preferably an ammonia-hydrogen peroxide solution mixture, ammonia water, a tetramethylammonium hydroxide aqueous solution, or a trimethyl-2-hydroxyethylammonium hydroxide aqueous solution.

[0032] In the above configuration, the surface modification unit may be an ultraviolet irradiation unit that irradiates the surface of the protected layer with ultraviolet light in an atmosphere containing oxygen atoms. By irradiating the surface of the protected layer with ultraviolet light in an atmosphere containing oxygen atoms, the ultraviolet irradiation unit can impart hydroxyl groups to the surface of the protected layer. This minimizes the areas where SAM molecules cannot chemisorb, allowing more SAM molecules to chemisorb at high density to the surface of the protected layer. As a result, a SAM with excellent density and protective performance can be formed.

[0033] Furthermore, the above-described configuration preferably further includes a pretreatment liquid supply unit that supplies a pretreatment liquid containing hydrogen fluoride to the surface of the layer to be protected before the surface is modified by the surface modification unit. By supplying a pretreatment liquid containing hydrogen fluoride to the surface of the layer to be protected in advance by the pretreatment liquid supply unit before surface modification is performed, hydroxyl groups can be effectively introduced when the surface modification is performed by the surface modification unit. As a result, SAM molecules can be chemically adsorbed to the surface of the layer to be protected at an even higher density, resulting in the formation of a SAM with even greater density and protective performance.

[0034] According to the present invention, it is possible to provide a substrate processing method and substrate processing apparatus, as well as a semiconductor device manufacturing method and semiconductor manufacturing apparatus, which are capable of effectively suppressing or reducing the occurrence of film defects and efficiently forming a self-assembled monolayer on a substrate surface that has high film density, fineness, and excellent protective performance in a shorter time than conventional methods.

[0035] 2A and 2B are cross-sectional views schematically showing a laminate provided on a substrate, in which FIG. 2A shows the state before the etching process and FIG. 2B shows the state after the etching process. FIG. 2A is a partially enlarged view of the portion surrounded by A in FIG. 1A, and FIG. 2B shows the SiO ２ 4(a) is a partial enlarged view showing a state in which a SAM is formed on the surface of the layer, and FIG. 4(c) is a partial enlarged view of the part surrounded by B in the stack of FIG. 1(b), showing a state in which the SiN layer has been etched. FIG. 4(a) is a flowchart showing an example of the overall flow of the method for manufacturing a semiconductor device according to the first embodiment of the present invention. FIG. 4(b) is a partial enlarged view showing a state in which a SAM is formed on the surface of the layer, and FIG. 4(c) is a partial enlarged view of the part surrounded by B in the stack of FIG. 1(b), showing a state in which the SiN layer has been etched. ２ FIG. 4(b) is an explanatory diagram conceptually showing the surface state of the SiO layer after surface modification. ２ 4(c) is a diagram conceptually illustrating the surface state of the layer, and FIG. ２ 5(a) is an explanatory diagram showing how SAM molecules are supplied to the surface of a layer. ２ 5(b) is an explanatory diagram showing the chemical adsorption of SAM molecules onto the surface of a layer. ２5( a ) and 5 ( b ) are explanatory views showing the state in which a SAM is formed by self-organization on the surface of a layer, and FIG. 5( c ) is an explanatory view showing the state in which SAM molecules remaining on the SAM have been removed. FIG. 5( a ) is an explanatory view showing the schematic configuration of a semiconductor manufacturing apparatus according to a first embodiment of the present invention. FIG. 5( a ) is an explanatory view showing the schematic configuration of a pretreatment liquid reservoir in a pretreatment liquid supply unit in the semiconductor manufacturing apparatus according to the first embodiment of the present invention. FIG. 5( b ) is an explanatory view showing the schematic configuration of a surface modification liquid reservoir provided in a surface modification liquid supply unit in the semiconductor manufacturing apparatus according to the first embodiment of the present invention. FIG. 5( c ) is an explanatory view showing the schematic configuration of a treatment liquid reservoir and an ultrasonic application unit in a treatment liquid supply unit in the semiconductor manufacturing apparatus according to the first embodiment of the present invention. FIG. 5( a ) is an explanatory view showing the schematic configuration of a removal liquid reservoir provided in a removal liquid supply unit in the semiconductor manufacturing apparatus according to the first embodiment of the present invention. FIG. 5( b ) is an explanatory view showing the schematic configuration of an etching liquid reservoir in an etching liquid supply unit in the first embodiment of the present invention. FIG. 5( c ) is a flowchart showing an example of the overall flow of a method for manufacturing a semiconductor device according to a second embodiment of the present invention. FIG. 5( a ) is an explanatory view showing the schematic configuration of a semiconductor manufacturing apparatus according to a second embodiment of the present invention. 1 is a side view showing a schematic configuration of a lifter in a semiconductor manufacturing apparatus according to a second embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a state in which a plurality of substrates on which SAMs are formed are immersed in an etching solution in the second embodiment of the present invention.

[0036] First Embodiment A first embodiment of the present invention will be described below.

[0037] [Substrate Processing Method (Semiconductor Device Manufacturing Method)] First, a substrate processing method according to the present embodiment will be described below with reference to the drawings. The substrate processing method of the present embodiment provides a technique for enabling good selective etching when forming a three-dimensional structure, such as a three-dimensional NAND structure, on the surface of a substrate.

[0038] The substrate processing method of this embodiment can be applied to part of the process of forming a three-dimensional NAND structure on a substrate W made of silicon or the like. Therefore, hereinafter, an example in which the substrate processing method of this embodiment is applied to a semiconductor device manufacturing method will be described, more specifically, an example in which processing is performed on a substrate W provided with a three-dimensional stack 3 as shown in Fig. 1. Fig. 1 is a cross-sectional view schematically showing the stack provided on the substrate W, with Fig. 1(a) showing the state before the etching step and Fig. 1(b) showing the state after the etching step.

[0039] As shown in FIG. 2( a ), the laminate 3 is formed by depositing a SiO 2 film, which functions as an interlayer insulating layer, on a substrate W. ２ The stack 3 includes a structure in which a layer 1 and a SiN layer 2 functioning as a sacrificial layer are alternately stacked. The stack 3 is provided with a plurality of memory trenches 4 extending through the stack 3 in a direction perpendicular to the surface of the substrate W. Note that Fig. 2(a) is a partial enlarged view of the portion surrounded by A in the stack of Fig. 1(a).

[0040] 3, the method for manufacturing a semiconductor device according to this embodiment includes at least a self-assembled monolayer (hereinafter referred to as "SAM") formation step S1 and an etching step S2, and enables selective etching of the SiN layer 2 through the memory trench 4 to form a recess on the side surface of the memory trench 4 in the stack 3. FIG. 3 is a flowchart showing an example of the overall flow of the method for manufacturing a semiconductor device according to this embodiment.

[0041] <SAM Formation Step> In the SAM formation step S1, a SAM as a protective layer is formed on a SiO ２ 3, the SAM formation step S1 includes at least a pretreatment step S101, a surface modification step S102, a treatment solution preparation step S103, a film formation step S104, a removal step S105, and a drying step S106. The SAM formation step S1 corresponds to the substrate processing method of the present invention.

[0042] 1. Pretreatment Step The pretreatment step S101 is to remove the SiO ２ It is physically adsorbed on the surface of layer 1 and formed into particles or thin films of SiO２ The pretreatment step S101 is a step of removing organic molecules covering the surface of the layer 1. This step is optional, but is preferably performed from the viewpoint of improving the surface modification of the substrate W in the surface modification step S102 described below. Specifically, the pretreatment step S101 is performed by bringing a pretreatment liquid into contact with the surface of the substrate W.

[0043] The method for contacting the pretreatment liquid with the substrate W is not particularly limited, and examples thereof include a method of applying the pretreatment liquid to the surface of the substrate W, a method of spraying the pretreatment liquid onto the surface of the substrate W, and a method of immersing the substrate W in the pretreatment liquid.

[0044] One method for applying the pretreatment liquid to the surface of the substrate W is, for example, to supply the pretreatment liquid to the central portion of the surface of the substrate W while the substrate W is being rotated at a constant speed around its central portion as an axis. In this manner, the pretreatment liquid supplied to the surface of the substrate W flows from near the center of the surface of the substrate W toward the peripheral edge of the substrate W due to centrifugal force generated by the rotation of the substrate W, and is spread over the entire surface of the substrate W. As a result, the entire surface of the substrate W is covered with the pretreatment liquid, and a liquid film of the pretreatment liquid is formed.

[0045] The conditions for contacting the substrate W with the pretreatment liquid are not particularly limited, but the time for which the substrate W is contacted with the pretreatment liquid (when the substrate W is immersed in the pretreatment liquid, the immersion time) is not particularly limited and can be set appropriately. However, by contacting the substrate W with the pretreatment liquid for 1 minute or less, the SiO ２ This can prevent the surface portion of the layer from being etched excessively.

[0046] The temperature of the pretreatment solution is not particularly limited and can be set as needed, for example, to room temperature. In this specification, "room temperature" means a temperature range of 5°C to 35°C.

[0047] The pretreatment liquid is not particularly limited, and examples thereof include hydrofluoric acid (for example, HF:deionized water (DIW)=1:100 in volume ratio).

[0048] 2. Surface Modification Step (Wet Method) The surface modification step S102 is carried out by, for example, applying a SiO ２This is a process for surface modification of the area on the surface of layer 1 where chemisorption of SAM molecules is difficult to achieve, to an area where chemisorption by SAM molecules is possible. Furthermore, this process enables chemisorption of SAM molecules at a higher density in the area where chemisorption of SAM molecules is possible. Figure 4(a) shows the SiO before surface modification. ２ FIG. 2 is an explanatory diagram conceptually showing the surface state of layer 1.

[0049] Surface modification step S102 ２ When the surface of layer 1 is modified, hydroxyl groups are provided on the surface, which enable chemical adsorption of SAM molecules, as shown in Figure 4(b). ２ FIG. 2 is an explanatory diagram conceptually showing the surface state of layer 1.

[0050] In this embodiment, SiO ２ The surface of the layer 1 is modified by a wet method. More specifically, the surface is modified by bringing a surface modification liquid into contact with the surface of the substrate W after the pretreatment step S101. The method for bringing the surface modification liquid into contact with the surface of the substrate W is not particularly limited, and examples thereof include a method of applying the surface modification liquid to the surface of the substrate W, a method of spraying the surface modification liquid onto the surface of the substrate W, and a method of immersing the substrate W in the surface modification liquid.

[0051] Furthermore, as a method for applying the surface modification liquid to the surface of the substrate W, for example, there is a method in which the surface modification liquid is supplied to the central portion of the surface of the substrate W while the substrate W is being rotated at a constant speed around its central portion as an axis. In this way, the surface modification liquid supplied to the surface of the substrate W flows from near the center of the surface of the substrate W toward the peripheral portion of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and is spread over the entire surface of the substrate W. As a result, the entire surface of the substrate W is covered with the surface modification liquid, and a liquid film of the surface modification liquid is formed.

[0052] The surface modification liquid is SiO ２ There are no particular limitations on the surface modifying liquid as long as it can provide hydroxyl groups to the surface of the layer 1. Specific examples of the surface modifying liquid include an ammonia-hydrogen peroxide solution mixture (Standard Clean-1 (SC-1)) (in terms of volume ratio, ammonium water (NH ３Concentration 28%): Hydrogen peroxide (H ２ O ２ Examples of alkaline solutions include aqueous solutions containing 30% ammonium hydroxide (DIW:DIW=1:4:20), aqueous ammonia, tetramethylammonium hydroxide solution, and trimethyl-2-hydroxyethylammonium hydroxide solution. ２ From the viewpoint of being able to apply the solution to the layer well, an ammonia-hydrogen peroxide solution mixture or the like is preferred.

[0053] The conditions for contacting the substrate W with the surface modification liquid are not particularly limited, but the time for contacting the substrate W with the surface modification liquid (when the substrate W is immersed in the surface modification liquid, the immersion time) is not particularly limited and can be set appropriately. However, by contacting the substrate W with the surface modification liquid for 10 minutes or more, the SiO ２ It is possible to provide a sufficient number of hydroxyl groups on the surface of the layer 1. This reduces the area where molecules capable of forming a SAM (hereinafter sometimes referred to as "SAM molecules") cannot be chemically adsorbed, and the SAM molecules are adsorbed onto SiO ２ It can be chemically adsorbed at a high density onto the surface of layer 1. As a result, it is possible to suppress the occurrence of film defects and efficiently form a SAM with excellent density and protective performance in a short time.

[0054] The temperature of the surface modifying liquid is not particularly limited, and can be set to, for example, room temperature or the like as needed.

[0055] When the surface modification step S102 is performed using a wet method, a cleaning step to remove the surface modification liquid and a drying step may be performed sequentially immediately after the surface modification step S102. The cleaning method used in the cleaning step is not particularly limited, and examples include a method of supplying a cleaning liquid to the surface of the substrate W or a method of immersing the substrate W in a cleaning liquid. Examples of cleaning liquids include toluene, decane, and 1,3-bis(trifluoromethyl)benzene. These solvents can be used alone or in combination. The cleaning conditions, such as the cleaning time and the temperature of the cleaning liquid, are not particularly limited and can be set as needed. The drying step is intended to remove any remaining cleaning liquid from the surface of the substrate W. The drying method is not particularly limited, and examples include a method of spraying an inert gas, such as nitrogen gas, onto the surface of the substrate W. The drying conditions, such as the drying time and the drying temperature, are not particularly limited and can be set as needed.

[0056] 3. Treatment Liquid Preparation Step The treatment liquid preparation step S103 is a step of preparing a treatment liquid containing SAM molecules. ２ It is used to form a SAM on the surface of the layer 1. The treatment liquid is prepared, for example, as follows.

[0057] First, a dispersion liquid in which water is uniformly dispersed in an organic solvent as a main solvent is prepared. "Uniform dispersion of water in an organic solvent" means, for example, that water is present in the organic solvent in the form of an emulsion. Furthermore, the "main solvent" refers to the solvent with the largest volume ratio when a mixed solvent consisting of multiple solvents is used.

[0058] Examples of organic solvents serving as the main solvent include ether solvents, aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, fluorine-containing solvents, and ketone-containing solvents. The ether solvent is not particularly limited, and examples thereof include tetrahydrofuran (THF). The aromatic hydrocarbon solvent is not particularly limited, and examples thereof include toluene. The aliphatic hydrocarbon solvent is not particularly limited, and examples thereof include decane. The fluorine-containing solvent is not particularly limited, and examples thereof include 1,3-bis(trifluoromethyl)benzene. The ketone-containing solvent is not particularly limited, and examples thereof include methyl ethyl ketone. These solvents can be used alone or in combination of two or more. Of the solvents listed above, aromatic hydrocarbon solvents are preferred, and toluene is particularly preferred, from the viewpoint of affinity with water. Furthermore, the organic solvent serving as the main solvent is preferably one having low water solubility. This allows water to be well dispersed in the organic solvent. Examples of organic solvents having low water solubility include the aforementioned toluene.

[0059] The amount of water added to the dispersion is preferably in the range of 50 ppm to 200 ppm, more preferably 50 ppm to 150 ppm. By adding 50 ppm or more of water, it is possible to prevent the hydrolysis reaction of the hydrolytically reactive functional groups in the SAM molecules added when preparing the treatment solution from becoming insufficient. That is, a sufficient amount of SAM molecules with hydroxyl groups introduced can be present in the treatment solution during the treatment solution generation stage. As a result, it is possible to suppress the occurrence of film defects and form a highly dense SAM without having to contact the treatment solution with the substrate surface for a long period of time to form a dense SAM, as in conventional substrate treatment methods. On the other hand, by adding 200 ppm or less of water, it is possible to suppress excessive aggregation of SAM molecules with hydroxyl groups due to a dehydration condensation reaction. As a result, it is possible to suppress a decrease in the density of the SAM molecules chemically adsorbed to the substrate surface, thereby forming a highly dense SAM.

[0060] The method for preparing the dispersion is not particularly limited, and examples thereof include a method of mixing an organic solvent and water while applying ultrasonic waves, and a method of mixing an organic solvent and water and then applying ultrasonic waves. Applying ultrasonic waves can prevent the generation of a mixture separated into an organic solvent phase and an aqueous phase. The conditions for applying ultrasonic waves, specifically, for example, the application time, frequency, and sonic intensity, are not particularly limited as long as they are sufficient to disperse water in the organic solvent, and can be set appropriately as needed. The method for applying ultrasonic waves is also not particularly limited, and examples thereof include a method of immersing an ultrasonic vibrator in the mixture and vibrating the ultrasonic vibrator to apply ultrasonic waves.

[0061] The dispersion is preferably prepared in an atmosphere of an inert gas such as nitrogen gas, for example. If the preparation is performed in an environment in which moisture is present in the atmosphere, the moisture in the atmosphere will dissolve in the mixed liquid (or dispersion), making it impossible to obtain a dispersion with the desired moisture content, which is not preferable.

[0062] Next, a material capable of forming a SAM (hereinafter referred to as "SAM-forming material") is added to the prepared dispersion to prepare a treatment liquid. It is preferable to add the SAM-forming material to the dispersion without applying ultrasonic waves, and after adding the SAM-forming material to the dispersion. By not applying ultrasonic waves, the treatment liquid can be prepared so that the SAM molecules exist without agglomerating with each other. By preparing the treatment liquid so that the SAM molecules exist without agglomerating with each other, a SAM can be successfully formed in the film formation step S104 described below.

[0063] The SAM-forming material is not particularly limited as long as it has a functional group exhibiting hydrolysis reactivity and contains molecules capable of forming a SAM. Furthermore, the SAM-forming material is preferably one that has high affinity (solubility) for the aforementioned organic solvent. Specific examples of the SAM-forming material include octadecyltrichlorosilane (C １８ H ３７ SiCl ３ ), decyltrichlorosilane (C １０ H ２１ SiCl ３ ), trichloropropylsilane (C３ H ７ SiCl ３ ), trichloromethylsilane (CH ３ SiCl ３ The exemplified organosilane compounds have a trichlorosilyl group as a functional group exhibiting hydrolysis reactivity.

[0064] Before being added to the treatment liquid, the SAM molecule has a functional group that exhibits hydrolysis reactivity. Therefore, when the SAM-forming material is added to the dispersion, the functional group undergoes a hydrolysis reaction with the water molecules that are uniformly dispersed in the dispersion. As a result, the functional group that exhibits hydrolysis reactivity becomes a hydroxyl group (a functional group that can undergo a dehydration condensation reaction with a hydroxyl group). For example, when the SAM molecule is octadecyltrichlorosilane, the following reaction occurs: C １８ H ３７ SiCl ３ + 3H ２ O → C １８ H ３７ Si(OH) ３ + 3HCl ３ As a result, a treatment liquid can be obtained in which SAM molecules with hydroxyl groups (or silanol groups) introduced therein exist without agglomeration. By preparing a treatment liquid containing SAM molecules with hydroxyl groups introduced therein in advance, the hydrolysis reaction, which is the rate-limiting step in the SAM film formation process, can be omitted. As a result, SAM film formation can be achieved in a shorter time than with conventional treatment liquids.

[0065] The amount of the SAM-forming material added is preferably within a range of 0.05% by mass or more and 5% by mass or less relative to the total mass of the treatment liquid.

[0066] The treatment liquid may contain known additives as long as they do not impair the effects of the present invention. The additives are not particularly limited, and examples thereof include stabilizers and surfactants.

[0067] The preparation of the treatment liquid is preferably carried out in a stationary state. More specifically, when adding the SAM-forming material to the dispersion, it is not preferable to apply mechanical force such as stirring or shaking to the dispersion. When adding the SAM-forming material to the dispersion, if mechanical force such as stirring or shaking is applied to the dispersion, there is a possibility that the SAM molecules will aggregate together. However, by adding the SAM-forming material to the dispersion in a stationary state to prepare the treatment liquid, it is possible to further suppress the aggregation of the SAM molecules and generate a treatment liquid.

[0068] The water content in the treatment liquid is preferably in the range of 50 ppm to 200 ppm, and more preferably in the range of 50 ppm to 150 ppm.

[0069] The treatment solution preparation step S103 can be performed, for example, at room temperature and atmospheric pressure. In this specification, "atmospheric pressure" refers to pressure near the standard atmospheric state (standard atmospheric pressure), where the standard atmospheric state refers to a temperature of approximately 25°C and an atmospheric pressure of approximately 101 kPa absolute. "Atmospheric pressure" also includes pressures that are slightly positive or negative relative to the standard atmospheric pressure.

[0070] 4. Film Forming Step The film forming step S104 is a step of bringing a processing liquid containing a SAM-forming material into contact with the surface of the substrate W to form a SAM.

[0071] The method for contacting the processing liquid with the substrate W is not particularly limited, and examples include a method in which the processing liquid is applied to the surface of the substrate W, a method in which the processing liquid is sprayed onto the surface of the substrate W, and a method in which the substrate W is immersed in the processing liquid.

[0072] One method for applying the processing liquid to the surface of the substrate W is, for example, to supply the processing liquid to the central portion of the surface of the substrate W while the substrate W is being rotated at a constant speed around its central portion as an axis. In this way, the processing liquid supplied to the surface of the substrate W flows from near the center of the surface of the substrate W toward the peripheral portion of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and is spread over the entire surface of the substrate W. As a result, the entire surface of the substrate W is covered with the processing liquid, and a liquid film of the processing liquid is formed.

[0073] The conditions for bringing the processing liquid into contact with the substrate W are not particularly limited. However, the film formation step S104 of this embodiment can shorten the contact time of the processing liquid compared to when a SAM is formed by a conventional method. Specifically, the time required for the SAM formation step S1 (when the SAM is formed by immersing the substrate W in the processing liquid, the immersion time) can be appropriately set within a range of 1 minute to 1540 minutes, preferably 1 minute to 60 minutes, and more preferably 1 minute to 30 minutes, depending on the type of SAM-forming material, its concentration, the type of solvent, and the like.

[0074] Next, the process of forming a SAM will be described in more detail using an example in which the SAM-forming material is octadecyltrichlorosilane.

[0075] As shown in Fig. 4C, when the processing liquid is supplied to the surface of the substrate W, SAM molecules 5 in which hydroxyl groups have been introduced into octadecyltrichlorosilane are dispersed in the processing liquid at the beginning of the supply. ２ FIG. 1 is an explanatory diagram showing the state in which the material is supplied to the surface of layer 1.

[0076] Here, SiO ２ Hydroxyl groups have been introduced to the surface of the layer 1 in the surface modification step S102 described above. Therefore, the SAM molecules 5 undergo a dehydration condensation reaction with the hydroxyl groups, as shown in FIG. 5(a). More specifically, the hydroxyl groups of the SAM molecules 5 and the SiO ２ The hydroxyl groups on the surface of the layer 1 undergo a dehydration condensation reaction to form siloxane bonds, which convert the SAM molecules 5 into SiO ２ The SAM molecules 5 are chemically adsorbed on the surface of the layer 1. In the treatment solution, the SAM molecules 5 are present in a state where they are prevented from aggregating with each other. Therefore, the rate-determining step in the SAM film formation process is the separation of the hydroxyl groups of the SAM molecules 5 and the SiO ２ It is possible to promote the dehydration condensation reaction between the hydroxyl groups on the surface of the layer 1. In addition, the SAM molecules 5 are densely packed on the SiO ２ The SAM molecules 5 can be chemically adsorbed on the surface of the layer 1. In addition, FIG. 5(a) shows the SAM molecules 5 on the SiO ２ FIG. 2 is an explanatory diagram showing chemical adsorption on the surface of layer 1.

[0077] Next, the SAM molecule 5 is SiO２ When SAM molecules 5 are chemically adsorbed at a high density on the surface of layer 1, an island structure of SAM molecules 5 appears on the surface. Furthermore, in each island, the SAM molecules 5 self-organize and grow (expand) due to hydrophobic and electrostatic interactions with each other, ultimately forming a SAM 6 (see FIG. 5(b)). In FIG. 5(b), the SAM molecules 5 are SiO ２ FIG. 1 is an explanatory diagram showing the formation of a SAM 6 by self-organization on the surface of layer 1.

[0078] 5. Removal Step The removal step S105 is a step for removing the SiO ２ This is a step of removing the treatment solution remaining on the surface of the layer 1. This removes excess SAM molecules 5 that do not contribute to the formation of the SAM 6, more specifically, SiO ２ It is possible to remove the SAM molecules 5 that are not chemically adsorbed on the surface of the layer 1. As a result, it is possible to prevent a film made of unadsorbed SAM molecules 5 from being formed on the SAM 6, and it is possible to form a good monolayer.

[0079] The treatment liquid is SiO ２ The method for removing the layer 1 from the surface is not particularly limited, and examples include a method of applying the removal liquid to the surface of the substrate W, a method of spraying the removal liquid onto the surface of the substrate W, and a method of immersing the substrate W in the removal liquid.

[0080] One method for applying the removing liquid to the surface of the substrate W is, for example, to supply the removing liquid to the central portion of the surface of the substrate W while the substrate W is being rotated at a constant speed around its central portion as an axis. As a result, the removing liquid supplied to the surface of the substrate W flows from near the center of the surface of the substrate W toward the peripheral edge of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and is spread over the entire surface of the substrate W. As a result, the processing liquid on the surface of the substrate W is replaced with the removing liquid, and the entire surface of the substrate W is covered with the removing liquid, forming a liquid film of the removing liquid.

[0081] When the SAM-forming material is octadecyltrichlorosilane, the SiO ２ The surface of the layer 1 is as shown in FIG. ２SAM molecules 5 that do not contribute to the formation of the SAM 6 are removed from the surface of the layer 1 by the removal solution. ２ FIG. 2 is an explanatory diagram showing the removal of excess SAM molecules 5 from the surface of layer 1.

[0082] The remover is not particularly limited, but an organic solvent that dissolves the SAM-forming material and has low water solubility is preferred. If the remover is capable of dissolving the SAM-forming material, excess SAM molecules 5 that do not contribute to the formation of a SAM can be effectively removed from the surface. More specific examples of the remover include toluene, decane, and 1,3-bis(trifluoromethyl)benzene. These solvents can be used alone or in combination of two or more.

[0083] 6. Drying Step The purpose of the drying step S106 is to remove the removing liquid remaining on the surface of the substrate W. The drying method is not particularly limited, and examples thereof include a method of spraying an inert gas such as nitrogen gas onto the surface of the substrate W. Drying conditions such as drying time and drying temperature are not particularly limited as long as they are sufficient to remove the removing liquid, and can be set appropriately as needed.

[0084] As a result, in the SAM formation step S1, as shown in FIG. ２ In this embodiment, the SAM 6 having excellent density and protective properties can be formed on the surface of the layer 1. ２ Hydroxyl groups are introduced to the surface of the layer 1. This allows the SAM molecules 5 to be chemically adsorbed in areas where the SAM molecules 5 cannot be chemically adsorbed. Furthermore, by introducing more hydroxyl groups into areas where the SAM molecules 5 can be chemically adsorbed, the SAM molecules 5 can be densely adsorbed onto the SiO ２ The SAM molecules 5 can be chemisorbed onto the surface of the layer 1. As a result, the SAM molecules 5 can be attached to the SiO ２ Even if the layer 1 is not in contact with the surface for a long time, the occurrence of film defects is suppressed, and a SAM 6 having excellent density and protective performance can be efficiently formed in a short time.

[0085] In this embodiment, a rinsing step and another drying step may be performed immediately after the drying step S106. ２ The remover can be removed from the surface of the layer 1. Also, by carrying out another drying step, the rinse liquid used in the rinsing step can be removed.

[0086] The rinse liquid used in the rinse step is not particularly limited, and examples thereof include DIW, etc. The method for supplying the rinse liquid to the surface of the substrate W is not particularly limited, and examples thereof include a method of applying the rinse liquid to the surface of the substrate W, a method of spraying the rinse liquid onto the surface of the substrate W, and a method of immersing the substrate W in the rinse liquid.

[0087] One method for applying the rinse liquid to the surface of the substrate W is, for example, to supply the rinse liquid to the central portion of the surface of the substrate W while the substrate W is being rotated at a constant speed around its central portion as an axis. In this manner, the rinse liquid supplied to the surface of the substrate W flows from near the center of the surface of the substrate W toward the peripheral edge of the substrate W due to centrifugal force generated by the rotation of the substrate W, and is spread over the entire surface of the substrate W. As a result, the removing liquid on the surface of the substrate W is replaced with the rinse liquid, and the entire surface of the substrate W is covered with the rinse liquid, forming a liquid film of the rinse liquid.

[0088] The other drying step is intended to remove the rinse liquid remaining on the surface of the substrate W. The drying method is not particularly limited, and examples thereof include a method of spraying an inert gas such as nitrogen gas onto the surface of the substrate W. Drying conditions such as drying time and drying temperature are not particularly limited as long as they are sufficient to remove the rinse liquid, and can be set appropriately as needed.

[0089] <Etching Step (Single-Wafer Process)> The etching step S2 is a step of selectively etching the SiN layer 2, which is a sacrificial layer and also a layer to be etched. More specifically, this is a step of bringing an etching solution into contact with the SiN layer 2 through the memory trench 4 to remove the SiN layer 2. In this step, the SAM 6 is formed of SiO 2 as a protective layer. ２ It serves to protect layer 1. ２This effectively prevents the layer 1 from being etched.

[0090] A method for applying the etching liquid to the surface of the substrate W, for example, in the case of a single-wafer process, is to supply the etching liquid to the central portion of the surface of the substrate W while rotating the substrate W at a constant speed around its central portion as an axis. In this way, the etching liquid supplied to the surface of the substrate W flows from near the center of the surface of the substrate W toward the peripheral edge of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and is spread over the entire surface of the substrate W. As a result, the entire surface of the substrate W is covered with the etching liquid, and a liquid film of the etching liquid is formed.

[0091] The etching liquid can be appropriately selected in consideration of the constituent material of the layer to be etched, the etching rate, etc. When the layer to be etched is a SiN layer 2 as in this embodiment, the etching liquid may be, for example, phosphoric acid (H ３ P.O. ４ For example, an aqueous solution of HF and DIW or hydrofluoric acid (for example, a volume ratio of HF:DIW=1:100) can be used. The concentration of the etching solution can also be appropriately set in consideration of the constituent material of the layer to be etched, the etching rate, etc.

[0092] The etching temperature (i.e., the temperature of the etching solution) and the etching rate for the layer to be etched can be appropriately set in consideration of the constituent material of the layer to be etched.

[0093] It is preferable to sequentially perform a rinsing step to remove the etching liquid and a drying step immediately after the etching step S2. The rinsing method in the rinsing step is not particularly limited, and examples thereof include a method of supplying a rinsing liquid to the surface of the substrate W and a method of immersing the substrate W in the rinsing liquid. The rinsing liquid is not particularly limited, and examples thereof include DIW. Furthermore, cleaning conditions such as the rinsing time and the temperature of the rinsing liquid are not particularly limited and can be set appropriately as needed. The drying step is intended to remove the rinsing liquid remaining on the surface of the substrate W. The drying method is not particularly limited, and examples thereof include a method of spraying an inert gas such as nitrogen gas onto the surface of the substrate W. Drying conditions such as the drying time and drying temperature are not particularly limited, and can be set appropriately as needed.

[0094] As a result, in the etching step S2, only the SiN layer 2 can be selectively removed as shown in FIG. ２ In the layer 1, the SAM6 having excellent density and protective performance covers and protects the surface, so that the SiO ２ Layer 1 is etched, and the etched silicon component is precipitated, resulting in SiO ２ This prevents the silicon from adhering to the surface of the layer 1. Furthermore, it is possible to increase the tolerance for the silicon concentration contained in the etching solution such as phosphoric acid. Note that Fig. 2(c) is a partial enlarged view of the portion surrounded by B in the stack of Fig. 1(b), showing the state after the SiN layer 2 has been etched.

[0095] [Substrate Processing Apparatus (Semiconductor Manufacturing Apparatus)] Next, the substrate processing apparatus according to this embodiment will be described below by taking as an example a case where it is applied to a semiconductor manufacturing apparatus.

[0096] 6, the semiconductor manufacturing apparatus 100 includes a substrate holder 110 for holding a substrate W, a pretreatment liquid supply unit 120 for supplying a pretreatment liquid to the front surface Wf of the substrate W, a surface modification liquid supply unit (surface modification unit) 130 for supplying a surface modification liquid to the front surface Wf of the substrate W, a processing liquid supply unit 140 for supplying a processing liquid to the front surface Wf of the substrate W, an ultrasonic wave application unit, a removing liquid supply unit 150 for supplying a removing liquid, an inert gas supply unit (not shown) for supplying an inert gas, an etching liquid supply unit (etching unit) 160, a chamber 170 for accommodating the substrate W, a splash prevention cup 180 for collecting the processing liquid, a swivel drive unit 190 for independently swivelly driving the arms (described later) of each unit, and a control unit 300. The semiconductor manufacturing apparatus 100 may also include a loading / unloading unit (not shown) for loading and unloading the substrate W. 6 is an explanatory diagram showing the schematic configuration of a semiconductor manufacturing apparatus 100 according to this embodiment. In this figure, XYZ orthogonal coordinate axes are displayed as appropriate to clarify the directional relationships of the objects shown. Here, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction.

[0097] <Substrate Holding Unit> The substrate holding unit 110 is a means for holding the substrate W, and as shown in Fig. 6, holds and rotates the substrate W in a substantially horizontal position with the front surface Wf of the substrate W facing upward. The substrate holding unit 110 has a spin chuck 113 in which a spin base 111 and a rotation support shaft 112 are integrally connected. The spin base 111 has a substantially circular shape in a plan view, and a hollow rotation support shaft 112 extending substantially vertically is fixed to its center. The rotation support shaft 112 is connected to a rotation shaft of a chuck rotation mechanism 114 including a motor. The chuck rotation mechanism 114 is housed in a cylindrical casing 115, and the rotation support shaft 112 is supported by the casing 115 so as to be rotatable about a vertical rotation axis J1.

[0098] The chuck rotation mechanism 114 can rotate the rotation support shaft 112 about the rotation axis J1 by being driven by a chuck drive unit (not shown) of the control unit 300. As a result, the spin base 111 attached to the upper end of the rotation support shaft 112 rotates about the rotation axis J1 at a constant speed. The control unit 300 can adjust the rotation speed of the spin base 111 by controlling the chuck rotation mechanism 114 via the chuck drive unit.

[0099] A plurality of chuck pins 116 for gripping the peripheral edge of the substrate W are provided upright near the peripheral edge of the spin base 111. There is no particular limitation on the number of chuck pins 116 to be provided, but it is preferable to provide at least three or more in order to securely hold the circular substrate W. In this embodiment, three chuck pins 116 are arranged at equal intervals along the peripheral edge of the spin base 111. Each chuck pin 116 includes a substrate support pin that supports the peripheral edge of the substrate W from below, and a substrate holding pin that holds the substrate W by pressing against the outer peripheral edge surface of the substrate W supported by the substrate support pin.

[0100] <Pre-treatment Liquid Supply Unit> The pre-treatment liquid supply unit 120 according to this embodiment is a unit that supplies a pre-treatment liquid to the front surface Wf of the substrate W. As shown in FIG. 6 , the pre-treatment liquid supply unit 120 includes a pre-treatment liquid storage unit 121, a nozzle 122, and an arm 123.

[0101] 7, the pretreatment liquid storage unit 121 includes a pressurizing unit 124 and a pretreatment liquid tank 125. Note that, FIG. 7 is an explanatory diagram illustrating a schematic configuration of the pretreatment liquid storage unit 121 in the pretreatment liquid supply unit 120.

[0102] The pressurizing unit 124 includes a nitrogen gas supply source 124a, which is a gas supply source for pressurizing the inside of the pretreatment liquid tank 125, a pump (not shown) for pressurizing the nitrogen gas, a nitrogen gas supply pipe 124b, and a valve 124c provided midway along the nitrogen gas supply pipe 124b.

[0103] The nitrogen gas supply pipe 124b is connected to the treatment liquid tank 125. The valve 124c is electrically connected to the control unit 300, and the opening and closing of the valve 124c can be controlled by an operation command from the control unit 300. When the valve 124c is opened by an operation command from the control unit 300, nitrogen gas can be supplied to the treatment liquid tank 125.

[0104] The pretreatment liquid tank 125 may include an agitation unit that agitates the pretreatment liquid in the pretreatment liquid tank 125 and a temperature adjustment unit that adjusts the temperature of the pretreatment liquid (neither is shown). The agitation unit may include a rotation unit that agitates the pretreatment liquid and an agitation control unit that controls the rotation of the rotation unit. The agitation control unit is electrically connected to the control unit 300, and the rotation unit includes, for example, a propeller-shaped agitation blade at the lower end of the rotation shaft. The control unit 300 issues an operation command to the agitation control unit to rotate the rotation unit, thereby agitating the pretreatment liquid with the agitation blade. As a result, the concentration and temperature of the pretreatment liquid can be made uniform in the pretreatment liquid tank 125.

[0105] Furthermore, a discharge pipe 125a for supplying the pretreatment liquid to the nozzle 122 is connected to the pretreatment liquid tank 125. A discharge valve 125b is provided midway along the discharge pipe 125a. The discharge valve 125b is also electrically connected to the control unit 300. This allows the opening and closing of these valves to be controlled by an operation command from the control unit 300. When the discharge valve 125b is opened by an operation command from the control unit 300, the pretreatment liquid is pressure-fed to the nozzle 122 via the discharge pipe 125a.

[0106] The nozzle 122 is attached to the tip of a horizontally extending arm 123, and is positioned above the spin base 111 when discharging the pretreatment liquid. The arm 123 is connected to a rotation drive unit 190 via a rotation shaft (not shown). The rotation drive unit 190 is electrically connected to a control unit 300, and rotates the arm 123 in response to an operation command from the control unit 300. As the arm 123 rotates, the nozzle 122 also moves.

[0107] <Surface Modification Liquid Supply Unit (Surface Modification Unit)> The surface modification liquid supply unit 130 according to this embodiment is a unit that supplies a surface modification liquid to the front surface Wf of the substrate W. As shown in FIG. 6 , the surface modification liquid supply unit 130 includes a surface modification liquid storage unit 131, a nozzle 132, and an arm 133.

[0108] 8, the surface modification liquid storage unit 131 has a function of supplying the surface modification liquid to the nozzle 132, and includes a pressurizing unit 134 and a surface modification liquid tank 135. Fig. 8 is an explanatory diagram showing a schematic configuration of the surface modification liquid storage unit 131 in the surface modification liquid supply unit 130.

[0109] The pressurizing unit 134 includes a nitrogen gas supply source 134a, which is a gas supply source for pressurizing the surface modification liquid tank 135, a pump (not shown) for pressurizing the nitrogen gas, a nitrogen gas supply pipe 134b, and a valve 134c provided midway along the nitrogen gas supply pipe 134b.

[0110] The nitrogen gas supply pipe 134b is connected to the surface modification liquid tank 135. The valve 134c is electrically connected to the control unit 300, and the opening and closing of the valve 134c can be controlled by an operation command from the control unit 300. When the valve 134c is opened by an operation command from the control unit 300, nitrogen gas can be supplied to the surface modification liquid tank 135.

[0111] The surface modification liquid tank 135 may include an agitation unit that agitates the surface modification liquid in the surface modification liquid tank 135 and a temperature adjustment unit that adjusts the temperature of the surface modification liquid (neither is shown). Examples of the agitation unit include a rotation unit that agitates the surface modification liquid in the surface modification liquid tank 135 and an agitation control unit that controls the rotation of the rotation unit. The agitation control unit is electrically connected to the control unit 300, and the rotation unit is equipped with, for example, a propeller-shaped agitation blade at the lower end of the rotation shaft. The control unit 300 issues an operation command to the agitation control unit to rotate the rotation unit, thereby agitating the surface modification liquid with the agitation blade. As a result, the concentration and temperature of the surface modification liquid can be made uniform within the surface modification liquid tank 135.

[0112] Furthermore, a discharge pipe 135a for supplying the surface modification liquid to the nozzle 132 is connected to the surface modification liquid tank 135. A discharge valve 135b is provided midway along the discharge pipe 135a. The discharge valve 135b is electrically connected to the control unit 300. This allows the opening and closing of the discharge valve 135b to be controlled by an operation command from the control unit 300. When the discharge valve 135b is opened by an operation command from the control unit 300, the surface modification liquid is pressure-fed to the nozzle 132 via the discharge pipe 135a.

[0113] The nozzle 132 is attached to the tip of a horizontally extending arm 133, and is positioned above the spin base 111 when discharging the surface modification liquid. The arm 133 is connected to a rotation drive unit 190 via a rotation shaft (not shown). The rotation drive unit 190 is electrically connected to the control unit 300, and rotates the arm 133 in response to an operation command from the control unit 300. As the arm 133 rotates, the nozzle 132 also moves.

[0114] <Processing Liquid Supply Unit> The processing liquid supply unit 140 according to this embodiment is a unit that supplies a processing liquid to the front surface Wf of the substrate W. As shown in FIG. 6 , the processing liquid supply unit 140 includes a processing liquid storage unit 141, a nozzle 142, and an arm 143.

[0115] 9, the treatment liquid reservoir 141 includes an organic solvent supply unit 144, a water supply unit 145, a SAM-forming material supply unit 146, a treatment liquid tank 147, a temperature adjustment unit 148, and an inert gas supply unit 149. Note that, FIG. 9 is an explanatory diagram showing a schematic configuration of the treatment liquid reservoir 141 and the ultrasonic wave application unit 191 in the treatment liquid supply unit 140.

[0116] The organic solvent supply unit 144 includes an organic solvent reservoir 144a for storing an organic solvent, an organic solvent supply pipe 144b for supplying the organic solvent to the treatment liquid tank 147, and a valve 144c provided along the route of the organic solvent supply pipe 144b. The valve 144c is electrically connected to the control unit 300. This allows the opening and closing of the valve 144c to be controlled by an operation command from the control unit 300. When the valve 144c is opened by an operation command from the control unit 300, the organic solvent is supplied to the treatment liquid tank 147 via the organic solvent supply pipe 144b. The organic solvent in the organic solvent reservoir 144a is pressurized by a pressurizing means (not shown) and sent to the organic solvent supply pipe 144b. The pressurizing means is not particularly limited, and a known means such as a pump can be used.

[0117] The water supply unit 145 includes a water storage unit 145a that stores water, a water supply pipe 145b for supplying water to the treatment liquid tank 147, and a valve 145c provided midway along the water supply pipe 145b. The valve 145c is electrically connected to the control unit 300. This allows the opening and closing of the valve 145c to be controlled by an operation command from the control unit 300. When the valve 145c is opened by an operation command from the control unit 300, water is supplied to the treatment liquid tank 147 via the water supply pipe 145b. The water in the water storage unit 145a is pressurized by a pressurizing means (not shown) and sent to the water supply pipe 145b. The pressurizing means is not particularly limited, and a known means such as a pump can be used.

[0118] The SAM-forming material supply unit 146 includes a SAM-forming material storage unit 146a that stores the SAM-forming material, a SAM-forming material supply pipe 146b that supplies the SAM-forming material to the treatment liquid tank 147, and a valve 146c provided along the SAM-forming material supply pipe 146b. The valve 146c is electrically connected to the control unit 300. This allows the opening and closing of the valve 146c to be controlled by an operation command from the control unit 300. When the valve 146c is opened by an operation command from the control unit 300, the SAM-forming material is supplied to the treatment liquid tank 147 via the SAM-forming material supply pipe 146b. The SAM-forming material in the SAM-forming material storage unit 146a is pressurized by a pressurizing means (not shown) and sent to the SAM-forming material supply pipe 146b. The pressurizing means is not particularly limited, and a known means such as a pump can be used.

[0119] The treatment liquid tank 147 mixes the organic solvent supplied from the organic solvent supply unit 144 with the water supplied from the water supply unit 145, and the ultrasonic application unit 191 applies ultrasonic waves to the resulting mixture, thereby producing a dispersion in which water is uniformly dispersed in the organic solvent. Alternatively, the ultrasonic application unit 191 can apply ultrasonic waves while mixing the organic solvent supplied from the organic solvent supply unit 144 with the water supplied from the water supply unit 145, thereby producing the dispersion. Furthermore, a treatment liquid can be produced by supplying a SAM-forming material from the SAM-forming material supply unit 146 while the produced dispersion is stored in the tank.

[0120] The treatment liquid tank 147 may include a temperature adjustment unit 148 for adjusting the temperature of the dispersion liquid and treatment liquid stored therein. The temperature adjustment unit 148 is electrically connected to the control unit 300. The control unit 300 issues an operation command to the temperature adjustment unit 148, thereby controlling the liquid temperature of the dispersion liquid when the dispersion liquid is produced. This makes it possible to prevent water in the dispersion liquid from evaporating (evaporating) and causing a change in the composition of the dispersion liquid.

[0121] The inert gas supply unit 149 includes an inert gas supply source 149a which is a supply source for supplying inert gas into the processing liquid tank 147, a pump (not shown) for pressurizing the inert gas, an inert gas supply pipe 149b, and a valve 149c provided midway along the inert gas supply pipe 149b.

[0122] The inert gas supply pipe 149b is connected to the treatment liquid tank 147. The valve 149c is electrically connected to the control unit 300, and the opening and closing of the valve 149c can be controlled by an operation command from the control unit 300. When the valve is opened by an operation command from the control unit 300, the inert gas can be supplied to the treatment liquid tank 147. This allows the dispersion liquid and the treatment liquid to be produced in an inert gas atmosphere. The inert gas is not particularly limited, and examples thereof include nitrogen gas.

[0123] Furthermore, a discharge pipe 147a is connected to the treatment liquid tank 147 through a pipeline for supplying the treatment liquid to the nozzle 142. A discharge valve 147b is provided midway along the discharge pipe 147a. The discharge valve 147b is also electrically connected to the control unit 300. This allows the opening and closing of the discharge valve 147b to be controlled by an operation command from the control unit 300. When the discharge valve 147b and the valve 149c are opened and the valves 144c, 145c, and 146c are closed in response to an operation command from the control unit 300, the treatment liquid is pressure-fed to the nozzle 142 through the discharge pipe 147a.

[0124] The nozzle 142 is attached to the tip of a horizontally extending arm 143, and is positioned above the spin base 111 when discharging the treatment liquid. The arm 143 is connected to a rotation drive unit 190 via a rotation shaft (not shown). The rotation drive unit 190 is electrically connected to a control unit 300, and rotates the arm 143 in response to an operation command from the control unit 300. As the arm 143 rotates, the nozzle 142 also moves.

[0125] 9 , the ultrasonic wave application unit 191 is a unit that applies ultrasonic waves when generating a dispersion liquid in the treatment liquid tank 147 of the treatment liquid supply unit 140. The ultrasonic wave application unit 191 is electrically connected to the control unit 300, and the application of ultrasonic waves can be controlled by operation commands from the control unit 300.

[0126] The ultrasonic wave application unit 191 includes, for example, at least an ultrasonic vibrator provided in the treatment liquid tank 147 and an oscillator that applies a drive voltage to the ultrasonic vibrator (neither is shown). Examples of ultrasonic vibrators include one that includes a piezoelectric body such as piezoelectric ceramics and a pair of electrodes provided on the piezoelectric body. The pair of electrodes are in contact with the piezoelectric body and are also electrically connected to the oscillator. When the oscillator outputs, for example, a high-frequency voltage as a drive voltage to the ultrasonic vibrator in response to an operation command from the control unit 300, the drive voltage is applied between the pair of electrodes, thereby applying the drive voltage to the piezoelectric body. When the drive voltage is applied, the piezoelectric body vibrates by alternately contracting and expanding in response to the drive voltage from the oscillator. This allows ultrasonic waves to be applied to the mixture of water and organic solvent stored in the treatment liquid tank 147.

[0127] <Removing Liquid Supply Unit> The removing liquid supply unit 150 according to this embodiment is a unit that supplies a removing liquid to the front surface Wf of the substrate W. As shown in FIG. 6 , the removing liquid supply unit 150 includes a removing liquid storage unit 151, a nozzle 152, and an arm 153.

[0128] 10, the removing liquid reservoir 151 has a function of supplying the removing liquid to the nozzle 152, and includes a pressurizing unit 154 and a removing liquid tank 155. FIG. 10 is an explanatory diagram showing a schematic configuration of the removing liquid reservoir 151 in the removing liquid supply unit 150.

[0129] The pressurizing unit 154 includes a nitrogen gas supply source 154a, which is a gas supply source for pressurizing the inside of the removal liquid tank 155, a pump (not shown) for pressurizing the nitrogen gas, a nitrogen gas supply pipe 154b, and a valve 154c provided midway along the nitrogen gas supply pipe 154b.

[0130] The nitrogen gas supply pipe 154b is connected to the removal liquid tank 155. The valve 154c is electrically connected to the control unit 300, and the opening and closing of the valve 154c can be controlled by an operation command from the control unit 300. When the valve 154c is opened by an operation command from the control unit 300, nitrogen gas can be supplied to the removal liquid tank 155.

[0131] The remover tank 155 may include an agitator that agitates the remover liquid in the remover liquid tank 155 and a temperature adjuster that adjusts the temperature of the remover liquid (neither is shown). Examples of the agitator include a rotor that agitates the remover liquid in the remover liquid tank 155 and an agitation controller that controls the rotation of the rotor. The agitation controller is electrically connected to the controller 300, and the rotor has, for example, a propeller-shaped agitator blade at the bottom end of the rotation shaft. The controller 300 issues an operation command to the agitation controller to rotate the rotor, thereby agitating the remover liquid with the agitator blade. As a result, the concentration and temperature of the remover liquid can be made uniform within the remover liquid tank 155.

[0132] Furthermore, a discharge pipe 155a for supplying the removal liquid to the nozzle 152 is connected to the removal liquid tank 155. A discharge valve 155b is provided midway along the discharge pipe 155a. The discharge valve 155b is electrically connected to the control unit 300. This allows the opening and closing of the discharge valve 155b to be controlled by an operation command from the control unit 300. When the discharge valve 155b is opened by an operation command from the control unit 300, the removal liquid is pressure-fed to the nozzle 152 via the discharge pipe 155a.

[0133] The nozzle 152 is attached to the tip of a horizontally extending arm 153, and is positioned above the spin base 111 when discharging the removal solution. The arm 153 is connected to a rotation drive unit 190 via a rotation shaft (not shown). The rotation drive unit 190 is electrically connected to a control unit 300, and rotates the arm 153 in response to an operation command from the control unit 300. As the arm 153 rotates, the nozzle 152 also moves.

[0134] <Inert Gas Supply Unit> The inert gas supply unit is a unit that supplies an inert gas to the front surface Wf of the substrate W. The inert gas supply unit has an inert gas reservoir, a nozzle, and an arm (none of which are shown).

[0135] The inert gas storage unit has a function of supplying an inert gas to the nozzle, and includes an inert gas tank for storing the inert gas, an inert gas temperature adjusting unit for adjusting the temperature of the inert gas stored in the inert gas tank, and piping. The inert gas stored in the inert gas tank can be, for example, nitrogen gas.

[0136] The inert gas temperature adjusting unit is electrically connected to the control unit 300, and adjusts the temperature by heating or cooling the inert gas stored in the inert gas tank in response to an operation command from the control unit 300. The inert gas temperature adjusting unit is not particularly limited, and any known temperature adjusting mechanism such as a Peltier element or a pipe through which temperature-adjusted water flows can be used.

[0137] The inert gas storage section is connected to the nozzle via a pipe, and a valve is inserted in the middle of the pipe. The inert gas in the inert gas tank is pressurized by a pressurizing means (not shown) and sent to the pipe. The pressurizing means can be realized by pressurizing with a pump or the like, or by compressing and storing the inert gas in the inert gas tank.

[0138] The valve is electrically connected to the control unit 300 and is normally closed. Opening and closing of the valve is controlled by an operation command from the control unit 300. When the valve is opened by an operation command from the control unit 300, an inert gas is supplied from the nozzle to the front surface Wf of the substrate W through a pipe.

[0139] The nozzle is attached to the tip of a horizontally extending arm, and is positioned above the spin base 111 when discharging the inert gas. The arm is connected to a rotation drive unit 190 via a rotation shaft (not shown). The rotation drive unit 190 is electrically connected to the control unit 300, and rotates the arm in response to an operation command from the control unit 300. As the arm rotates, the nozzle also moves.

[0140] <Etching Liquid Supply Unit (Etching Unit)> The etching liquid supply unit 160 is a unit that supplies an etching liquid to the front surface Wf of the substrate W. As shown in FIG. 6 , the etching liquid supply unit 160 has an etching liquid storage unit 161, a nozzle 162, and an arm 163.

[0141] 11, the etching liquid storage unit 161 includes at least an etching liquid tank 164, a temperature regulator 165, a liquid feed pump 166, and a particle filter 167. Note that, FIG. 11 is an explanatory diagram showing a schematic configuration of the etching liquid storage unit 161 in the etching liquid supply unit 160.

[0142] The etching solution tank 164 may include an agitation unit (not shown) that agitates the etching solution in the etching solution tank 164. Examples of the agitation unit include a rotation unit that agitates the etching solution and an agitation control unit that controls the rotation of the rotation unit. The agitation control unit is electrically connected to the control unit 300, and the rotation unit is equipped with, for example, a propeller-shaped agitation blade at the lower end of the rotation shaft. The control unit 300 issues an operation command to the agitation control unit to rotate the rotation unit, thereby agitating the etching solution with the agitation blade. As a result, the concentration and temperature of the etching solution in the etching solution tank 164 can be made uniform.

[0143] The etching solution tank 164 is provided with a mixer 168 that can mix chemicals and DIW from an external supply source (not shown) to prepare an etching solution of a predetermined concentration. The chemicals are solutes that function as etchants. Examples of chemicals include the aforementioned phosphoric acid and hydrogen fluoride.

[0144] A discharge pipe 169 for supplying the etching liquid to the nozzle 162 is also connected to the etching liquid tank 164. A temperature regulator 165, a liquid feed pump 166, and a particle filter 167 are sequentially installed along the discharge pipe 169 from upstream to downstream. The temperature regulator 165 and the liquid feed pump 166 are electrically connected to the control unit 300. This allows the temperature of the etching liquid supplied to the nozzle 162 to be controlled by an operation command from the control unit 300. Furthermore, when the liquid feed pump 166 is controlled by an operation command from the control unit 300, the etching liquid can be pressure-fed to the nozzle 162 via the discharge pipe 169. The particle filter 167 can remove foreign matter such as particles from the etching liquid.

[0145] The nozzle 162 is attached to the tip of a horizontally extending arm 163, and is positioned above the spin base 111 when discharging the etching solution. The arm 163 is connected to a rotation drive unit 190 via a rotation shaft (not shown). The rotation drive unit 190 is electrically connected to a control unit 300, and rotates the arm 163 in response to an operation command from the control unit 300. As the arm 163 rotates, the nozzle 162 also moves.

[0146] <Scatter prevention cup> The scatter prevention cup 180 is provided to surround the spin base 111. The scatter prevention cup 180 is connected to a lifting drive mechanism (not shown) and is capable of moving up and down in the vertical direction. When supplying a processing liquid or the like to the front surface Wf of the substrate W, the scatter prevention cup 180 is positioned at a predetermined position by the lifting drive mechanism and surrounds the substrate W held by the chuck pins 116 from a lateral position. This makes it possible to collect processing liquid or the like that splashes from the substrate W and the spin base 111.

[0147] <Control Unit> The control unit 300 is electrically connected to each component of the semiconductor manufacturing equipment and controls the operation of each component. The control unit 300 is composed of a computer having an arithmetic unit and a memory unit. The arithmetic unit uses a CPU that performs various arithmetic operations. The memory unit also includes a ROM (read-only memory) that stores the substrate processing program and the etching processing program, a RAM (readable / writable memory) that stores various information, and a magnetic disk that stores control software and data. The magnetic disk pre-stores processing conditions, including the conditions for generating (mixing) the dispersion liquid and the processing liquid; the supply conditions for the pretreatment liquid, surface modification liquid, processing liquid, removal liquid, inert gas, and etching liquid; the application conditions for ultrasonic waves; the rinsing conditions; the drying conditions; the SAM film formation conditions; and the etching conditions. The CPU loads the processing conditions into the RAM and controls each component of the semiconductor manufacturing equipment according to the contents of the RAM.

[0148] Second Embodiment A second embodiment of the present invention will be described below. This embodiment differs from the first embodiment in that the surface modification process is performed by a dry method using ultraviolet irradiation. It also differs in that the etching process is performed by a batch method instead of a single-wafer method. Even with this configuration, a SAM with high film density and excellent compactness, which effectively suppresses or reduces the occurrence of film defects and has excellent protective performance, can be formed on the substrate surface more efficiently and in a shorter time than conventional film formation methods.

[0149] [Substrate Processing Method (Semiconductor Device Manufacturing Method)] A substrate processing method (semiconductor device manufacturing method) according to this embodiment will be described below. Fig. 12 is a flowchart showing an example of the overall flow of a substrate processing method according to a second embodiment of the present invention.

[0150] 12, the pretreatment step S101, the treatment liquid preparation step S103, the film formation step S104, the removal step S105, and the drying step S106 are the same as those in the first embodiment, and therefore, detailed descriptions of these steps will be omitted.

[0151] 1. Surface Modification Step (Dry Method) The surface modification step S102′ is the same as the surface modification step S102 in the first embodiment, except for SiO２ This is a process for modifying the surface of layer 1 so that regions where SAM molecules are difficult to chemisorb are converted into regions where SAM molecules can chemisorb, and also to regions where SAM molecules can chemisorb at high density.

[0152] In this embodiment, SiO ２ The surface of the layer 1 is modified by a dry method using ultraviolet irradiation. In the case of ultraviolet irradiation, the ultraviolet irradiation conditions such as the wavelength of the light source, irradiation intensity, and irradiation time are set to a value that allows SiO 2 to be chemically adsorbed onto the SAM molecules 5. ２ There are no particular limitations as long as hydroxyl groups can be introduced onto the surface of the layer 1. The ultraviolet irradiation is carried out in an atmosphere containing oxygen atoms, such as air.

[0153] <Etching Step (Batch Method)> The etching step S2' is a step of selectively etching the SiN layer 2, which is the layer to be etched, by immersing the substrate W after the SAM formation in an etching solution.

[0154] The method of immersing the substrate W in the etching solution is, for example, performed with the substrate W in an upright position. Here, "upright position" refers to a position in which the surface of the substrate W is aligned in a direction approximately perpendicular to a horizontal plane, and includes a vertical position. The etching solution may be the same as that described in the first embodiment. Furthermore, the etching temperature (i.e., the liquid temperature of the etching solution) and the etch rate for the layer to be etched may be appropriately set in consideration of the constituent material of the layer to be etched, as in the first embodiment.

[0155] [Substrate Processing Apparatus (Semiconductor Manufacturing Apparatus)] Next, the substrate processing apparatus according to this embodiment will be described below by taking as an example a case where it is applied to a semiconductor manufacturing apparatus.

[0156] The semiconductor manufacturing apparatus of this embodiment differs from the substrate processing apparatus of the first embodiment in that it includes at least a single-wafer substrate processing unit for forming a SAM and a batch-type etching processing unit for etching the layer to be etched.

[0157] <Substrate Processing Unit> As shown in FIG. 13 , the substrate processing unit 200 of this embodiment differs from the semiconductor manufacturing apparatus 100 of the first embodiment in that it includes an ultraviolet irradiation unit 210 as a surface modification unit instead of a surface modification liquid supply unit. FIG. 13 is an explanatory diagram showing the schematic configuration of the substrate processing unit of this embodiment. In this figure, some of the components common to the semiconductor manufacturing apparatus 100 of the first embodiment are omitted. In addition, in this figure, XYZ orthogonal coordinate axes are displayed as appropriate to clarify the directional relationships of the illustrated objects. Here, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction.

[0158] The ultraviolet ray irradiation unit 210 is disposed above the substrate holding unit 110 (in the direction indicated by arrow Z in FIG. 13 ) inside the chamber 170 so as to be able to irradiate ultraviolet rays onto the front surface Wf of the substrate W held by the substrate holding unit 110. The ultraviolet ray irradiation unit 210 includes at least a plurality of light source units 211 and quartz glass 212.

[0159] The light source unit 211 shown in FIG. 13 is a line light source, and is arranged so that its longitudinal direction is parallel to the direction indicated by Y in FIG. 13. The light source units 211 are also arranged in the direction indicated by arrow X so that they are equally spaced from one another. However, the light source unit 211 of the present invention is not limited to this form. For example, ring-shaped light source units with different diameters may be arranged concentrically. The light source unit may also be a point light source. In this case, it is preferable that the multiple light source units are arranged so that they are equally spaced from one another in a plane.

[0160] The type of light source unit 211 is not particularly limited, and for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a potassium lamp, a mercury-xenon lamp, a flash lamp, an excimer lamp, a metal halide lamp, and a UV (ultraviolet)-LED (Light Emitting Diode) can be used. The multiple light source units 211 may be of the same type or different types. When multiple different types of light source units 211 are used, they can be arranged so that the peak wavelengths, light intensities, etc. are different from each other.

[0161] The quartz glass 212 is disposed between the light source unit 211 and the substrate W. The quartz glass 212 is a plate-like body and is disposed parallel to the horizontal direction. The quartz glass 212 is optically transparent to ultraviolet light, heat-resistant, and corrosion-resistant, and allows the ultraviolet light irradiated from the light source unit 211 to pass through, enabling irradiation of the surface Wf of the substrate W. Furthermore, the quartz glass 212 can protect the light source unit 211 from the atmosphere inside the chamber 170.

[0162] <Etching Processing Unit> The etching processing unit of this embodiment is a batch-type processing unit used to etch a layer to be etched, and performs an etching step S2' on substrates W on which SAMs have been formed in the substrate processing unit. As shown in FIGS. 14 and 15 , the etching processing unit includes at least a substrate transport unit (not shown), a lifter 220, and a processing tank 230 for storing an etching solution. FIG. 14 is a side view showing a schematic configuration of the lifter 220 in the semiconductor manufacturing apparatus of this embodiment. Also, FIG. 15 is a cross-sectional view showing a state in which multiple substrates W on which SAMs have been formed according to this embodiment are immersed in the etching solution.

[0163] The substrate transport unit transports the substrates W on which the SAM has been formed in the substrate processing unit to the etching processing unit. The substrate transport unit includes, for example, an articulated robot capable of transporting the substrates W. The tip of the articulated robot includes a transport arm capable of loading the substrates W all at once in a horizontal position.

[0164] As shown in FIG. 14 , the lifter 220 includes a flat back plate 221, multiple (three) holding bars 222, and a lifting mechanism (not shown). The back plate 221 is erected, and at its lower end, the holding bars 222 each extend in one direction perpendicular to the back plate 221. The holding bars 222 are provided with a plurality of grooves 223 arranged in the extending direction. The grooves 223 are spaced apart and equally spaced from one another. Each groove 223 extends in a direction perpendicular to the extending direction of the holding bar 222, allowing multiple substrates W to be fitted into the grooves 223 in an upright position. This allows the holding bars 222 to abut against and support the group of substrates W from below in an upright position, thereby holding them collectively. The number of holding bars 222 is not particularly limited, as long as there is more than one. The number of grooves 223 formed in the holding rod 222 is not particularly limited and may be set appropriately depending on the number of substrates W to be held. The lifting mechanism can raise or lower the lifter 220 in the Z direction shown in Fig. 15. This allows the lifter 220, which collectively holds the group of substrates W, to be moved into or removed from the processing bath 230.

[0165] 15 , the treatment tank 230 includes an injection pipe 231 that supplies the etching solution into the treatment tank 230, an inner tank 232 that stores the etching solution, and an outer tank 233 that is provided around the periphery of the upper opening of the inner tank 232. The injection pipe 231 is provided at the bottom of the inner tank 232 and enables the etching solution to be supplied in an upflow manner to the inner tank 232. The outer tank 233 also enables the etching solution that overflows from the inner tank 232 to be collected. The injection pipe 231 may be connected to the etching solution storage section 161 described in the first embodiment via a discharge pipe 169, for example.

[0166] (Other Matters) In the above description, the most preferred embodiment of the present invention has been described. However, the present invention is not limited to this embodiment. For example, in the first embodiment, SiN ２Although the etching process for the layer has been described as being performed by a single wafer process, the etching process may also be performed by a batch process as described in the second embodiment. Furthermore, although the surface modification process has been described as being performed by a wet process as an example in the first embodiment, the surface modification process may also be performed by a dry process using ultraviolet light irradiation as described in the second embodiment. Even in these modes, a SAM with high film density and excellent compactness, in which the occurrence of film defects is effectively suppressed or reduced, and excellent protective performance can be formed on the substrate surface more efficiently and in a shorter time than with conventional film formation methods.

[0167] Preferred examples of the present invention are described in detail below. However, the materials, amounts, conditions, etc. described in these examples are not intended to limit the scope of the present invention unless otherwise specified.

[0168] (Example 1) SiO ２ A substrate having a film (thickness 100 nm) formed thereon was prepared and immersed in a hydrogen fluoride aqueous solution (pretreatment solution) for 1 minute (pretreatment step) in which the volume ratio of hydrogen fluoride to DIW was 1:100.

[0169] Next, the substrate was removed from the hydrogen fluoride solution and immersed in a surface modification liquid for 10 minutes (surface modification step). The surface modification liquid was SC-1 (volume ratio: ammonium water (NH ３ Concentration 28%): Hydrogen peroxide (H ２ O ２ A concentration of 30% (DIW:DIW=1:4:20) was used.

[0170] Separately from the substrate surface modification process, a treatment solution was also prepared. Specifically, in a stationary sealed container, 100 ppm of water was added to toluene as an organic solvent at a temperature of 23°C and atmospheric pressure. Furthermore, ultrasonic waves were applied to the toluene and water mixture for 30 minutes while the container was left stationary. This resulted in a dispersion in which water was uniformly dispersed in toluene as the primary solvent. The ultrasonic waves were applied at a frequency of 45 Hz. Next, octadecyltrichlorosilane, a SAM-forming material, was added to the stationary dispersion at a temperature of 23°C and atmospheric pressure to prepare a treatment solution (treatment solution preparation process). The content (concentration) of octadecyltrichlorosilane was 5% by mass relative to the total mass of the treatment solution.

[0171] Next, the substrate was removed from the surface modification liquid and immersed in a treatment liquid containing a SAM-forming material for 5 minutes to remove the SiO ２ A SAM (thickness: about 1 nm) was formed on the film surface (film formation step).

[0172] Next, the substrate was removed from the treatment solution and immersed in toluene as a remover for 1 minute to remove any unadsorbed SAM-forming material remaining on the surface of the substrate (removal step). Furthermore, the surface of the substrate on which the SAM was formed was dried by spraying nitrogen gas onto it (drying step). The temperature of the nitrogen gas was room temperature, and the drying time was 1 minute.

[0173] Next, the dried substrate was immersed in DIW to remove the toluene (rinsing step), and then the surface on which the SAM was formed was dried by blowing nitrogen gas onto it (drying step). The temperature of the nitrogen gas was room temperature. In this way, the sample according to this example was produced.

[0174] Next, the obtained sample was subjected to an etching treatment. Specifically, the substrate was immersed in an etching solution, and the area on the substrate surface that was not protected by SAM was etched. The etching conditions were as follows: SiO ２The immersion time in the etching solution (etching time) was set to 195 seconds so that the etching depth was about 10 nm. The etching solution used was an aqueous hydrogen fluoride solution, and the volume ratio of hydrogen fluoride to DIW was set to hydrogen fluoride:DIW=1:100.

[0175] Next, the substrate was removed from the etching solution and immersed in DIW, and then removed from the DIW (rinsing step with DIW). The etched surface was then dried by spraying nitrogen gas at room temperature (drying step).

[0176] In this example, the surface modification treatment for the substrate after the pretreatment step was changed to a method using ultraviolet light irradiation. Otherwise, samples were prepared in the same manner as in Example 1, and the obtained samples were then subjected to an etching treatment.

[0177] The ultraviolet irradiation conditions were as follows: Light source of ultraviolet irradiation unit: low-pressure mercury lamp (product name: EUV200WS-51, manufactured by Sen Special Light Sources Co., Ltd.) Peak wavelength of ultraviolet light: 185 nm, 254 nm Irradiation intensity of ultraviolet light: 10 mW / cm ２ Ultraviolet irradiation time: 15 minutes Pressure in the chamber: atmospheric pressure Temperature in the chamber: 23°C Atmosphere in the chamber: air

[0178] In this comparative example, the water content in the treatment solution was changed to 300 ppm, and the surface modification treatment for the substrate after the pretreatment step was changed to an annealing treatment. Except for these, samples were prepared in the same manner as in Example 1, and the obtained samples were then subjected to an etching treatment.

[0179] The annealing conditions were a heating temperature of 600° C. and a heating time of 30 minutes. After the annealing treatment, the substrate was allowed to cool naturally until it reached room temperature.

[0180] Comparative Example 2 In this comparative example, the heating temperature in the annealing treatment was changed to 300° C. Except for this, a sample was prepared in the same manner as in Comparative Example 1, and the obtained sample was then subjected to an etching treatment.

[0181] Comparative Example 3 In this comparative example, the substrate after the pretreatment step was not subjected to a surface modification treatment, but otherwise a sample was prepared in the same manner as in Example 1, and the obtained sample was then subjected to an etching treatment.

[0182] Comparative Example 4 In this comparative example, instead of the surface modification liquid consisting of SC-1, hydrochloric acid hydrogen peroxide solution (SC-2) (volume ratio: hydrochloric acid (concentration 36%): hydrogen peroxide solution (concentration 30-36%): DIW = 1:1:5) was used. Except for this, samples were prepared in the same manner as in Example 1, and the obtained samples were subjected to an etching treatment.

[0183] In this comparative example, nitric acid (volume ratio of nitric acid to DIW = 1:3) was used instead of the surface modification liquid composed of SC-1. Except for this, a sample was prepared in the same manner as in Example 1, and the obtained sample was subjected to an etching treatment.

[0184] (Evaluation of SiOH / Si) For each sample according to Examples 1 and 2 and Comparative Examples 1 to 5, SiOH / Si was measured at two points by XPS analysis using an XPS measurement device (product name: Quantera SXM, manufactured by PHI Corporation) as the measurement device, and the average value was calculated. The results are shown in Table 1.

[0185] (Evaluation of SAM Density) For each of the samples according to Examples 1 and 2 and Comparative Examples 1 to 5, the area ratio (%) of the SAM film defects was calculated to evaluate the SAM density.

[0186] Specifically, the SAM of each sample was imaged using an atomic force microscope (AFM) (trade name: Dimension Icon, manufactured by Bruker Japan Co., Ltd.) to obtain a 500 nm square observation image (AFM image). Next, each obtained observation image was binarized and then image processed to map the film defects and identify the locations (regions) of the SAM film defects. The identification of the locations (regions) of the SAM film defects by mapping was performed by taking into account that the SAM film thickness was approximately 1 nm, and image processing was performed so that defects located at a depth of less than 1 nm from the SAM surface were mapped. This ensured that locations (regions) deeper than 1 nm from the SAM surface, more specifically, etched regions, were mapped as SAM film defect regions and were not included in the area. Next, the areas of the SAM film defects identified by image processing were calculated, and the ratio of their areas to the total area in the observation image was calculated. The results are shown in Table 1.

[0187] (Results) As can be seen from Table 1, it was confirmed that in Example 1, in which surface modification was performed using SC-1 as the surface modification liquid, and Example 2, in which surface modification was performed by ultraviolet irradiation, the SiOH / Si values ​​increased compared to Comparative Example 3, in which no surface modification treatment was performed. On the other hand, it was confirmed that in Comparative Examples 1 and 2, in which surface modification was performed by annealing treatment, Comparative Example 4, in which surface modification was performed using SPM as the surface modification liquid, and Comparative Example 5, in which surface modification was performed using nitric acid as the surface modification liquid, the SiOH / Si values ​​remained unchanged or decreased compared to Comparative Example 3. This shows that when surface modification treatment was performed using SC-1 as the surface modification liquid or when surface modification treatment was performed by ultraviolet irradiation, SiO ２ It was confirmed that hydroxyl groups could be effectively provided on the layer.

[0188] Furthermore, the area ratios (%) of film defects in the SAMs in Examples 1 and 2 were 10.7% and 10.0%, respectively, which were reduced compared to Comparative Example 3, which was not subjected to surface modification treatment, and Comparative Examples 1, 2, 4, and 5, which were subjected to surface modification treatment by other methods. This confirmed that the SAMs in Examples 1 and 2 all had good density and protective performance.

[0189]

[0190] 1 SiO ２ 1. Layer (layer to be protected) 2. SiN layer (layer to be etched) 3. Laminate 4. Memory trench 5. SAM (self-assembled monolayer) molecule 6. SAM (self-assembled monolayer) 100. Semiconductor manufacturing apparatus 110. Substrate holder 120. Pre-treatment liquid supply unit 121. Pre-treatment liquid reservoir 130. Surface modification liquid supply unit 131. Surface modification liquid reservoir 140. Treatment liquid supply unit 141. Treatment liquid reservoir 144. Organic solvent supply unit 145. Water supply unit 146. SAM-forming material supply unit 150. Removal liquid supply unit 151. Removal liquid reservoir 160. Etching liquid supply unit 161. Etching liquid reservoir 190. Swivel drive unit 200. Substrate processing unit 210. Ultraviolet irradiation unit 220. Lifter 230. Processing tank 231. Injection pipe 232 Inner tank 233 Outer tank 300 Control unit S1 SAM (self-assembled monolayer) forming step S2, S2' Etching step S101 Pretreatment step S102, S102' Surface modification step S103 Treatment liquid preparation step S104 Film formation step S105 Removal step S106 Drying step W Substrate Wf Surface of substrate

Claims

1. A substrate processing method for forming a self-assembled monolayer on a surface of a substrate, comprising: a surface modification step of modifying the surface of the substrate by adding hydroxyl groups to the surface of the substrate; and a film formation step of contacting the surface of the substrate after the surface modification step with a treatment liquid containing molecules capable of forming the self-assembled monolayer to form the self-assembled monolayer, wherein the molecules have functional groups capable of undergoing a dehydration condensation reaction with the hydroxyl groups, and the film formation step is a step of chemically adsorbing the molecules onto the surface of the substrate by a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

2. The substrate processing method according to claim 1, wherein the surface modification step is a step of contacting the surface of the substrate with a surface modification liquid consisting of an alkaline solution.

3. The substrate processing method according to claim 2, wherein the alkaline solution is an ammonia-hydrogen peroxide solution mixture, ammonia water, a tetramethylammonium hydroxide solution, or a trimethyl-2-hydroxyethylammonium hydroxide solution.

4. The substrate processing method according to claim 1, wherein the surface modification step is a step of irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms.

5. The substrate processing method according to claim 1, further comprising a pretreatment step of contacting the surface of the substrate with a pretreatment liquid containing hydrogen fluoride prior to the surface modification step.

6. A method for manufacturing a semiconductor device, comprising processing a substrate having a laminate provided on its surface, the laminate including an alternate stack of a protected layer to be protected during etching and a layer to be etched to be etched, the method comprising: selectively forming a self-assembled monolayer on at least a surface of the protected layer; and selectively etching the layer to be etched using the self-assembled monolayer as a protective layer, the method for forming the self-assembled monolayer including: a surface modification step of modifying the surface of the protected layer by adding a hydroxyl group to the surface of the protected layer; and a film formation step of contacting the surface of the protected layer after the surface modification step with a treatment liquid including molecules capable of forming the self-assembled monolayer to form the self-assembled monolayer, the molecules having functional groups capable of undergoing a dehydration condensation reaction with the hydroxyl groups, and the film formation step is a step of chemically adsorbing the molecules to the surface of the protected layer by a dehydration condensation reaction between the hydroxyl group and the functional group of the molecule.

7. The method for manufacturing a semiconductor device according to claim 6, wherein the surface modification step is a step of bringing a surface modification liquid made of an alkaline solution into contact with the surface of the layer to be protected.

8. The method for manufacturing a semiconductor device according to claim 7, wherein the alkaline solution is a mixture of ammonia and hydrogen peroxide, ammonia water, a tetramethylammonium hydroxide solution, or a trimethyl-2-hydroxyethylammonium hydroxide solution.

9. The method for manufacturing a semiconductor device according to claim 6, wherein the surface modification step is a step of irradiating the surface of the layer to be protected with ultraviolet light in an atmosphere containing oxygen atoms.

10. The method for manufacturing a semiconductor device according to claim 6, further comprising a pretreatment step of contacting the surface of the layer to be protected with a pretreatment liquid containing hydrogen fluoride prior to the surface modification step.

11. A substrate processing apparatus for forming a self-assembled monolayer on a surface of a substrate, comprising: a surface modification unit for modifying the surface of the substrate by adding hydroxyl groups; and a processing liquid supply unit for forming the self-assembled monolayer by supplying a processing liquid containing molecules capable of forming the self-assembled monolayer to the surface of the substrate modified by the surface modification unit, wherein the molecules have functional groups capable of undergoing a dehydration condensation reaction with the hydroxyl groups, and the processing liquid supply unit chemically adsorbs the molecules onto the surface of the substrate by a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

12. The substrate processing apparatus according to claim 11, wherein the surface modifying section is a surface modifying liquid supplying section that supplies a surface modifying liquid made of an alkaline solution to the surface of the substrate.

13. The substrate processing apparatus according to claim 12, wherein the alkaline solution is an ammonia-hydrogen peroxide solution mixture, ammonia water, a tetramethylammonium hydroxide solution, or a trimethyl-2-hydroxyethylammonium hydroxide solution.

14. The substrate processing apparatus according to claim 11, wherein the surface modification section is an ultraviolet irradiating section that irradiates the surface of the substrate with ultraviolet rays in an atmosphere containing oxygen atoms.

15. The substrate processing apparatus according to claim 11, further comprising a pre-treatment liquid supplying section that supplies a pre-treatment liquid containing hydrogen fluoride to the surface of the substrate before the surface is modified by the surface modifying section.

16. A semiconductor manufacturing apparatus for processing a substrate having a laminate provided on its surface, the laminate including an alternating layer of a protected layer to be protected by etching and an etched layer to be etched, the semiconductor manufacturing apparatus comprising: a surface modification unit for modifying the surface of the protected layer by adding hydroxyl groups; a processing liquid supply unit for forming a self-assembled monolayer by supplying a processing liquid including molecules capable of forming a self-assembled monolayer to the surface of the protected layer modified by the surface modification unit; and an etching unit for selectively etching and removing the etched layer using the self-assembled monolayer as a protective layer, the molecules having functional groups capable of undergoing a dehydration condensation reaction with the hydroxyl groups, and the processing liquid supply unit chemically adsorbs the molecules to the surface of the protected layer by a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

17. A semiconductor manufacturing apparatus for processing a substrate having a laminate provided on its surface, the laminate including an alternating layer of a protected layer to be protected by etching and a layer to be etched to be etched, the apparatus comprising: a substrate processing unit for selectively forming a self-assembled monolayer on at least a surface of the protected layer; and an etching processing unit for selectively etching and removing the layer to be etched using the self-assembled monolayer as a protective layer, the substrate processing unit comprising: a surface modification section for modifying the surface of the protected layer by adding hydroxyl groups to the surface of the protected layer; and a processing liquid supply section for forming the self-assembled monolayer by supplying a processing liquid including molecules capable of forming the self-assembled monolayer to the surface of the protected layer modified by the surface modification section, the molecules having functional groups capable of undergoing a dehydration condensation reaction with the hydroxyl groups, and the processing liquid supply section chemically adsorbs the molecules to the surface of the protected layer by a dehydration condensation reaction between the hydroxyl groups and the functional groups of the molecules.

18. The semiconductor manufacturing apparatus according to claim 16 or 17, wherein the surface modifying section is a surface modifying liquid supplying section that supplies a surface modifying liquid made of an alkaline solution to the surface of the layer to be protected.

19. The semiconductor manufacturing equipment according to claim 18, wherein the alkaline solution is an ammonia-hydrogen peroxide mixture, an ammonia solution, an aqueous solution of tetramethylammonium hydroxide, or an aqueous solution of trimethyl-2-hydroxyethylammonium hydroxide.

20. The semiconductor manufacturing apparatus according to claim 16 or 17, wherein the surface modification section is an ultraviolet irradiation section which irradiates the surface of the layer to be protected with ultraviolet light in an atmosphere containing oxygen atoms.

21. The semiconductor manufacturing apparatus according to claim 16 or 17, further comprising a pre-treatment liquid supplying section that supplies a pre-treatment liquid containing hydrogen fluoride to the surface of the layer to be protected before it is surface-modified by the surface modifying section.

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