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

Abstract

To provide: a substrate processing method and a substrate processing device, capable of forming a self-assembled monolayer (SAM) on a substrate surface efficiently and in a short time, the SAM having excellent denseness and protection performance due to suppression or reduction in the occurrence of film defects; a method for manufacturing a semiconductor device; and a semiconductor manufacturing device.SOLUTION: A substrate processing method includes: a surface modification step S102 for performing surface modification that enables formation of a SAM on a surface of a substrate; a first contact step S104 for bringing a first treatment liquid containing a first molecule capable of forming a SAM into contact with the surface of the substrate after the surface modification step S102 and thereby forming a SAM; and a second contact step S106 for bringing a second treatment liquid containing a second molecule of the same kind as or different kind from the first molecule into contact with the surface of the substrate after the first contact step S104, and thereby chemically adsorbing the second molecule in a region where the SAM is not formed. The second contact step S106 is performed at least once until the area ratio (%) of a film defect of the SAM formed on the surface of the substrate becomes equal to or less than an arbitrarily set threshold.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a substrate processing method and substrate processing 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. [Background technology]

[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 a dual damascene structure having trenches and via holes is formed by photolithography and etching, and a conductive film such as Cu is embedded in the trenches and via holes to form wiring.

[0003] However, in recent years, semiconductor devices have become increasingly miniaturized, and there are cases where the alignment accuracy of photolithography is insufficient. For this reason, there is a demand for an alternative to photolithography to selectively form a film in a specific region on the substrate surface with high accuracy.

[0004] For example, Patent Document 1 discloses a method for selectively etching a silicon nitride (SiN) film and a silicon oxide (SiO2) film on a substrate, in which a thermal phosphoric acid resistant material is formed as a SAM on the surface of the silicon oxide film in advance 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 deposition methods, it is difficult to deposit such a highly dense SAM in a short time, resulting in poor production efficiency. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent No. 5490071 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in consideration of the above 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, which are capable of efficiently forming 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. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the substrate processing method according to 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 to enable the formation of the self-assembled monolayer; a first contact step of contacting the surface of the substrate after the surface modification step with a first treatment liquid containing first molecules capable of forming the self-assembled monolayer to form the self-assembled monolayer; and a second contact step of contacting the surface of the substrate after the first contact step with a second treatment liquid containing second molecules identical or different to the first molecules to chemically adsorb the second molecules to areas where the self-assembled monolayer is not formed, wherein the second contact step is performed at least once until an area ratio (%) of film defects in the self-assembled monolayer formed on the surface of the substrate becomes equal to or less than an arbitrarily set threshold value.

[0009] According to the above-mentioned configuration, first, in the surface modification step, a surface modification that enables the formation of a self-assembled monolayer (hereinafter, sometimes referred to as "SAM") is performed on the substrate surface. Then, in the first contact step, a first processing liquid containing a first molecule capable of forming a SAM is brought into contact with the substrate surface after the surface modification. As a result, the first molecule is chemically adsorbed on the substrate surface and self-assembled to form a SAM. Here, in the SAM formed in the first contact step, the first molecule may not be chemically adsorbed on the substrate surface locally, resulting in film defects. In particular, when the contact time of the first molecule with the substrate surface is short, the frequency of film defects in the surface increases, or the area of ​​the film defects becomes large. However, in the above-mentioned configuration, in the second contact step, a second processing liquid containing a second molecule of the same or different type as the first molecule is brought into contact with the substrate surface after the first contact step. As a result, the second molecule is chemically adsorbed to the area where the SAM is not formed, thereby reducing or repairing the film defects of the SAM. Moreover, this second contact step is performed at least once until the area ratio (%) of film defects in the SAM becomes equal to or less than an arbitrarily set threshold value. Therefore, in the above-mentioned configuration, unlike the conventional substrate processing method, the occurrence of film defects can be suppressed without the need to keep the SAM molecules in contact with the substrate surface for a long time to form a dense SAM, and a SAM with excellent denseness and protective performance can be efficiently formed in a short time.

[0010] In the above-mentioned configuration, it is preferable that the second molecule has a molecular chain length equal to or shorter than that of the first molecule. This can prevent or reduce the inability of the second molecule to chemisorb to the substrate surface due to steric hindrance between the second molecule and the first molecule already chemisorbed to the substrate surface. As a result, it is possible to further reduce or repair film defects in the SAM, and form a SAM with excellent density and protective performance.

[0011] In the above-mentioned configuration, when the second contact step is performed multiple times, it is preferable that the second molecule used in the earlier step has a molecular chain length equal to or longer than that of the second molecule used in the later step. This makes it possible to prevent or reduce the inability of the second molecule to be chemically adsorbed in the later step to be chemically adsorbed due to steric hindrance between the first molecule and the second molecule already chemically adsorbed on the substrate surface, even when the second contact step is performed multiple times. As a result, it is possible to further reduce or repair film defects in the SAM, and form a SAM with excellent density and protective performance.

[0012] In the above configuration, it is preferable that the first molecule and the second molecule have functional groups capable of dehydration condensation reactions with hydroxyl groups, the surface modification step is a step of imparting the hydroxyl groups to the surface of the substrate, and the first contact step and the second contact step are steps of chemically adsorbing the first molecule or the second molecule to the surface of the substrate by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the substrate.

[0013] Furthermore, in the above-mentioned configuration, the surface modification step can be a step of providing the hydroxyl groups to the surface of the substrate by contacting the surface of the substrate with a surface modification liquid made of an alkaline solution, or by irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms. This allows the introduction of hydroxyl groups in the surface modification step to be performed satisfactorily. As a result, the SAM molecules can be chemically adsorbed to the surface of the substrate with even higher density, and a SAM with even better density and protective performance can be formed.

[0014] In order to solve the above-mentioned problems, the method for manufacturing a semiconductor device according to the present invention is a method for manufacturing a semiconductor device, which includes processing a substrate having a laminate provided on a surface thereof, the laminate including an alternately laminated layer to be protected during etching and an etched layer to be etched, the method including a step of selectively forming a self-assembled monolayer on at least a surface of the protected layer, and a step of selectively etching the etched layer using the self-assembled monolayer as a protective layer, the step of forming the self-assembled monolayer including a surface modification step of modifying the surface of the protected layer to enable the formation of the self-assembled monolayer. a first contact step of contacting the surface of the protected layer after the surface modification step with a first treatment liquid containing first molecules capable of forming the self-assembled monolayer to form the self-assembled monolayer; and a second contact step of contacting the surface of the substrate after the first contact step with a second treatment liquid containing second molecules identical or different to the first molecules to chemically adsorb the second molecules in areas where the self-assembled monolayer is not formed, wherein the second contact step is performed at least once until the defect area ratio (%) of the self-assembled monolayer formed on the surface of the protected layer becomes equal to or less than an arbitrarily set threshold value.

[0015] According to the above-mentioned configuration, first, in the surface modification step, the surface of the layer to be protected is modified to enable the formation of a SAM. Then, in the first contact step, a first processing liquid containing a first molecule capable of forming a SAM is brought into contact with the surface of the layer to be protected after the surface modification. As a result, the first molecule is chemically adsorbed to the surface of the layer to be protected and self-assembled to form a SAM. Here, in the SAM formed in the first contact step, the first molecule may not be chemically adsorbed locally on the surface of the layer to be protected, resulting in film defects. In particular, when the contact time of the first molecule with the surface of the layer to be protected is short, the frequency of film defects in the surface increases, or the area of ​​the film defects becomes large. However, in the above-mentioned configuration, in the second contact step, a second processing liquid containing a second molecule of the same or different type as the first molecule is brought into contact with the surface of the layer to be protected after the first contact step. As a result, the second molecule is chemically adsorbed to the area where the SAM is not formed, thereby reducing or repairing the film defects of the SAM. Moreover, this second contact step is performed at least once until the area ratio (%) of film defects in the SAM becomes equal to or less than an arbitrarily set threshold value. Therefore, in the above-mentioned configuration, unlike the conventional semiconductor device manufacturing method, the occurrence of film defects can be suppressed without having to keep the SAM molecules in contact with the surface of the layer to be protected for a long period of time in order to form a dense SAM, and a SAM with excellent denseness and protective performance can be efficiently formed in a short period of time.

[0016] In the above-mentioned configuration, it is preferable that the second molecule has a molecular chain length equal to or shorter than that of the first molecule. This can prevent or reduce the inability of the second molecule to chemically adsorb to the surface of the layer to be protected due to steric hindrance between the second molecule and the first molecule already chemically adsorbed to the surface of the layer to be protected. As a result, it is possible to further reduce or repair film defects in the SAM, and form a SAM with excellent density and protective performance.

[0017] Furthermore, in the above-mentioned configuration, when the second contact step is performed multiple times, it is preferable that the second molecule used in the earlier step has a molecular chain length equal to or longer than that of the second molecule used in the later step. This makes it possible to prevent or reduce the inability of the second molecule to be chemically adsorbed in the later step to be chemically adsorbed due to steric hindrance between the first molecule and the second molecule already chemically adsorbed on the surface of the layer to be protected, even when the second contact step is performed multiple times. As a result, it is possible to further reduce or repair film defects in the SAM, and form a SAM with excellent density and protective performance.

[0018] Furthermore, in the above-mentioned configuration, it is preferable that the first molecule and the second molecule have functional groups capable of dehydration condensation reactions with hydroxyl groups, the surface modification process is a process of imparting the hydroxyl groups to the surface of the protected layer, and the first contact process and the second contact process are processes of chemically adsorbing the first molecule or the second molecule to the surface of the protected layer by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the protected layer.

[0019] Furthermore, in the above-mentioned configuration, the surface modification step can be a step of providing the hydroxyl groups to the surface of the substrate by contacting the surface of the substrate with a surface modification liquid made of an alkaline solution, or by irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms. This allows the introduction of hydroxyl groups in the surface modification step to be performed satisfactorily. As a result, the SAM molecules can be chemically adsorbed to the surface of the layer to be protected with even higher density, and a SAM with even better density and protective performance can be formed.

[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 a surface of a substrate, and is characterized in that it comprises a surface modification unit that performs surface modification on the surface of the substrate to enable the formation of the self-assembled monolayer, and a first processing liquid supply unit that forms the self-assembled monolayer by supplying a first processing liquid containing first molecules capable of forming the self-assembled monolayer to the surface of the substrate that has been surface-modified by the surface modification unit, and the second processing liquid supply unit supplies the second processing liquid at least once until the area ratio (%) of film defects of the self-assembled monolayer formed on the surface of the substrate becomes equal to or less than an arbitrarily set threshold value.

[0021] According to the above-mentioned configuration, the surface modification unit performs surface modification on the substrate surface, thereby enabling the formation of a SAM. The first processing liquid supply unit supplies the first processing liquid containing the first molecule that enables the formation of a SAM to the substrate surface after the surface modification, thereby chemically adsorbing the first molecule to form a SAM. Here, in the SAM formed on the substrate surface, the first molecule may not be chemically adsorbed locally on the substrate surface, resulting in film defects. In particular, when the contact time of the first molecule with the substrate surface is short, the frequency of film defects in the surface increases, or the area of ​​the film defects becomes large. However, the above-mentioned configuration further includes a second processing liquid supply unit that supplies a second processing liquid containing a second molecule that is the same or different from the first molecule to the substrate surface. This allows the second molecule to be chemically adsorbed even in areas where the SAM is not formed, thereby reducing or repairing film defects in the SAM. The second processing liquid supply unit supplies the second processing liquid at least once until the area ratio (%) of the film defects in the SAM becomes equal to or less than an arbitrarily set threshold value. Therefore, with the above configuration, the occurrence of film defects can be suppressed without the need to keep SAM molecules 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, and a SAM with excellent denseness and protective performance can be efficiently formed in a short period of time.

[0022] In the above configuration, the second molecule may have a molecular chain length equal to or shorter than that of the first molecule. This prevents or reduces the inability of the second molecule to chemically adsorb to the substrate surface due to steric hindrance between the second molecule and the first molecule already chemically adsorbed to the substrate surface. As a result, film defects in the SAM can be further reduced or repaired, and a SAM with excellent density and protective performance can be formed.

[0023] Furthermore, in the above configuration, when the second processing liquid supply unit supplies the second processing liquid to the surface of the substrate multiple times, it is preferable that the second molecule contained in the first processing liquid has a molecular chain length equal to or longer than that of the second molecule contained in the second processing liquid supplied later. This makes it possible to prevent or reduce the inability of the second molecule to be chemically adsorbed in a later step to be chemically adsorbed due to steric hindrance between the first molecule and the second molecule already chemically adsorbed on the substrate surface, even when the second processing liquid supply unit supplies the second processing liquid multiple times. As a result, it is possible to further reduce or repair film defects in the SAM, and form a SAM with excellent density and protective performance.

[0024] In the above configuration, it is preferable that the first molecule and the second molecule have functional groups capable of dehydration condensation reactions with hydroxyl groups, the surface modification unit performs the surface modification by imparting the hydroxyl groups to the surface of the substrate, and the first processing liquid supply unit and the second processing liquid supply unit chemically adsorb the first molecule or the second molecule to the surface of the substrate by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the substrate.

[0025] Furthermore, in the above configuration, the surface modification unit is preferably a surface modification liquid supply unit that provides hydroxyl groups to the surface of the substrate by supplying a surface modification liquid made of an alkaline solution to the surface of the substrate, or an ultraviolet irradiation unit that provides hydroxyl groups to the surface of the substrate by irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms. The surface modification liquid supply unit and the ultraviolet irradiation unit can introduce more hydroxyl groups to the substrate surface. As a result, more SAM molecules can be chemically adsorbed to the substrate surface, and a SAM with excellent density and protective performance can be formed.

[0026] In order to solve the above-mentioned problems, the semiconductor manufacturing apparatus according to the present invention is a semiconductor manufacturing apparatus for processing a substrate having a laminate provided on its surface, the laminate including a layer to be protected from etching and a layer to be etched that is to be etched that are alternately laminated, the semiconductor manufacturing apparatus including a surface modification unit that performs surface modification on the surface of the layer to be protected to enable the formation of a self-assembled monolayer, a first processing liquid supply unit that forms the self-assembled monolayer by supplying a first processing liquid including first molecules capable of forming the self-assembled monolayer to the surface of the layer to be protected that has been surface-modified by the surface modification unit, and a second processing liquid supply unit that supplies the first processing liquid to the surface of the layer to be protected that has been surface-modified by the surface modification unit, the first processing liquid supply unit supplying the first processing liquid including first molecules capable of forming the self-assembled monolayer to the surface of the self-assembled monolayer. the second processing liquid supply unit supplies a second processing liquid containing second molecules, the same or different from the first molecules, to the surface of the protected layer on which a self-assembled monolayer is formed, thereby chemically adsorbing the second molecules in areas where the self-assembled monolayer is not formed, and an etching unit selectively etches and removes the layer to be etched, using the self-assembled monolayer as a protective layer, wherein the second processing liquid supply unit supplies the second processing liquid at least once until an area ratio (%) of film defects in the self-assembled monolayer formed on the surface of the protected layer becomes equal to or less than an arbitrarily set threshold value.

[0027] The semiconductor manufacturing apparatus of the above configuration enables excellent 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 performs surface modification on the surface of the layer to be protected, thereby enabling the formation of a SAM. The first processing liquid supply unit supplies a first processing liquid containing a first molecule that enables the formation of a SAM to the surface of the layer to be protected after the surface modification, thereby chemically adsorbing the first molecule to form a SAM. Here, in the SAM formed on the surface of the layer to be protected, the first molecule may not be locally chemically adsorbed on the surface of the layer to be protected, resulting in film defects. In particular, when the contact time of the first molecule with the surface of the layer to be protected is short, the frequency of film defects in the surface increases, or the area of ​​the film defects becomes large. However, the above configuration further includes a second processing liquid supply unit that supplies a second processing liquid containing a second molecule, which is the same or different from the first molecule, to the surface of the layer to be protected. This allows the second molecules to be chemically adsorbed even in areas where the SAM is not formed, thereby reducing or repairing film defects in the SAM. Furthermore, the second processing liquid supply unit supplies the second processing liquid at least once until the area ratio (%) of the SAM film defects becomes equal to or less than an arbitrarily set threshold value. Therefore, in the above configuration, unlike conventional semiconductor manufacturing equipment, the occurrence of film defects can be suppressed without having to keep the SAM molecules in contact with the surface of the layer to be protected for a long period of time to form a dense SAM, and a SAM with excellent denseness and protective performance can be efficiently formed in a short time.

[0028] In order to solve the above-mentioned problems, the semiconductor manufacturing apparatus according to the present invention is a semiconductor manufacturing apparatus for processing a substrate having a laminate provided on its surface, the laminate including a layer to be protected by etching and a layer to be etched that is to be etched that are alternately laminated, the semiconductor manufacturing apparatus including a substrate processing unit for selectively forming a self-assembled monolayer on at least the surface of the layer to be protected, 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 including a surface modification section for performing surface modification on the surface of the layer to be protected so as to enable the formation of the self-assembled monolayer, and a substrate processing unit for performing a surface modification process on the surface of the layer to be protected that is surface modified by the surface modification section. and a second processing liquid supply unit that supplies a second processing liquid containing a second molecule, the same or different from the first molecule, to the surface of the protected layer on which the self-assembled monolayer has been formed, thereby chemically adsorbing the second molecule in an area where the self-assembled monolayer has not been formed, wherein the second processing liquid supply unit supplies the second processing liquid at least once until an area ratio (%) of film defects in the self-assembled monolayer formed on the surface of the protected layer becomes equal to or less than an arbitrarily set threshold value.

[0029] The semiconductor manufacturing apparatus of the above configuration includes at least a substrate processing unit that selectively forms a SAM on the layer to be protected, and an etching processing unit that selectively etches and removes the layer to be etched. Before 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 the layer to be etched, thereby enabling excellent selective etching of the layer to be etched. In the above configuration, the surface modification unit performs surface modification on the surface of the layer to be protected, thereby enabling the formation of a SAM. In addition, the first processing liquid supply unit supplies a first processing liquid containing a first molecule that enables the formation of a SAM to the surface of the layer to be protected after the surface modification, thereby chemically adsorbing the first molecule to form a SAM. Here, in the SAM formed on the surface of the layer to be protected, film defects may occur because the SAM molecules cannot be locally chemically adsorbed on 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 occurrence of film defects in the surface increases, or the area of ​​the film defects becomes large. However, the above-mentioned configuration further includes a second processing liquid supply unit that supplies a second processing liquid containing a second molecule, which is the same or different from the first molecule, to the surface of the layer to be protected. This allows the second molecules to be chemically adsorbed even in areas where the SAM is not formed, thereby reducing or repairing film defects in the SAM. In addition, the second processing liquid supply unit supplies the second processing liquid at least once until the area ratio (%) of the SAM film defects becomes equal to or less than an arbitrarily set threshold value. Therefore, the above-mentioned configuration can suppress the occurrence of film defects without having to keep the SAM molecules in contact with the surface of the layer to be protected for a long time to form a dense SAM, as in conventional semiconductor manufacturing equipment, and can efficiently form a SAM with excellent denseness and protective performance in a short time.

[0030] In the above configuration, the second molecule may have a molecular chain length equal to or shorter than that of the first molecule. According to the above configuration, the surface modifying liquid supply unit supplies a surface modifying liquid made of an alkaline solution to the surface of the layer to be protected, thereby imparting hydroxyl groups to the surface of the layer to be protected. This makes it possible to minimize the area where SAM molecules having hydroxyl groups cannot be chemically adsorbed, and to allow 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 configuration, when the second processing liquid supply unit supplies the second processing liquid to the surface of the protected layer multiple times, it is preferable that the second molecule contained in the first processing liquid has a molecular chain length equal to or longer than that of the second molecule contained in the second processing liquid supplied later. This makes it possible to prevent or reduce the inability of the second molecule to be chemically adsorbed in a later step to be chemically adsorbed due to steric hindrance between the first molecule and the second molecule already chemically adsorbed to the surface of the protected layer, even when the second processing liquid supply unit supplies the second processing liquid multiple times. As a result, it is possible to further reduce or repair film defects in the SAM, and form a SAM with excellent density and protective performance.

[0032] In the above configuration, it is preferable that the first molecule and the second molecule have functional groups capable of dehydration condensation reactions with hydroxyl groups, the surface modification unit performs the surface modification by imparting the hydroxyl groups to the surface of the substrate, and the first processing liquid supply unit and the second processing liquid supply unit chemically adsorb the first molecule or the second molecule to the surface of the substrate by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the substrate.

[0033] Furthermore, in the above configuration, the surface modification unit is preferably a surface modification liquid supply unit that provides hydroxyl groups to the surface of the layer to be protected by supplying a surface modification liquid made of an alkaline solution to the surface of the layer to be protected, or an ultraviolet irradiation unit that provides hydroxyl groups to the surface of the layer to be protected by irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms. The surface modification liquid supply unit and the ultraviolet irradiation unit can introduce more hydroxyl groups 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 protection performance can be formed. Effect of the Invention

[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 having high film density and excellent compactness and protective performance on a substrate surface in a shorter time than conventional methods. [Brief description of the drawings]

[0035] [Figure 1] 1A and 1B are cross-sectional views each showing a schematic representation of a laminate provided on a substrate, in which FIG. 1A shows the state before an etching step, and FIG. 1B shows the state after the etching step. [Diagram 2] FIG. 2(a) is a partial enlarged view of the portion surrounded by A in the laminate in FIG. 1(a), FIG. 2(b) is a partial enlarged view showing the formation of a SAM on the surface of the SiO2 layer, and FIG. 2(c) is a partial enlarged view of the portion surrounded by B in the laminate in FIG. 1(b), showing the etching of the SiN layer. [Diagram 3] 3 is a flowchart showing an example of an overall flow of a method for manufacturing a semiconductor device according to a first embodiment of the present invention. [Figure 4]FIG. 4(a) is an explanatory diagram conceptually showing the surface state of the SiO2 layer before surface modification in the first embodiment, FIG. 4(b) is an explanatory diagram conceptually showing the surface state of the SiO2 layer after surface modification, and FIG. 4(c) is an explanatory diagram showing the state in which the first treatment liquid is supplied to the surface of the SiO2 layer. [Diagram 5] FIG. 5(a) is an explanatory diagram showing how the first molecules are chemically adsorbed onto the surface of the SiO2 layer, FIG. 5(b) is an explanatory diagram showing how the first molecules self-organize on the surface of the SiO2 layer to form a SAM, and FIG. 5(c) is an explanatory diagram showing how the second treatment liquid is supplied to the surface of the SiO2 layer. [Figure 6] FIG. 2 is an explanatory diagram showing the state of the SAM after densification treatment. [Figure 7] 1 is an explanatory diagram illustrating a schematic configuration of a semiconductor manufacturing apparatus according to a first embodiment of the present invention. [Figure 8] 1 is an explanatory diagram illustrating a schematic configuration of a pre-treatment liquid storage unit in a pre-treatment liquid supply unit in a semiconductor manufacturing apparatus according to a first embodiment of the present invention. FIG. [Figure 9] 1 is an explanatory diagram illustrating a schematic configuration of a surface modification liquid storage unit provided in a surface modification liquid supply unit in a semiconductor manufacturing apparatus according to a first embodiment of the present invention. FIG. [Figure 10] 1 is an explanatory diagram illustrating a schematic configuration of a first processing liquid storage unit and an ultrasonic wave application unit in a first processing liquid supply unit in a semiconductor manufacturing apparatus according to a first embodiment of the present invention. FIG. [Figure 11] FIG. 2 is an explanatory diagram illustrating a schematic configuration of an etching liquid storage section in an etching liquid supply section in the first embodiment of the present invention. [Figure 12] 10 is a flowchart showing an example of an overall flow of a method for manufacturing a semiconductor device according to a second embodiment of the present invention. [Figure 13] FIG. 11 is an explanatory diagram illustrating a schematic configuration of a semiconductor manufacturing apparatus according to a second embodiment of the present invention. [Figure 14] 11 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. FIG. [Figure 15]FIG. 11 is a cross-sectional view showing a state in which a plurality of substrates on which a SAM is formed are immersed in an etching solution in a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[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 is applicable to a part of a process for 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 manufacturing method of a semiconductor device, more specifically, a case in which processing is performed on a substrate W provided with a three-dimensional stack 3 as shown in Fig. 1 will be described. Fig. 1 is a cross-sectional view that shows a schematic representation of a stack provided on a substrate W, where Fig. 1(a) shows a state before an etching process and Fig. 1(b) shows a state after the etching process.

[0039] As shown in Fig. 2(a), the laminate 3 includes a structure in which SiO2 layers 1 functioning as interlayer insulating layers and SiN layers 2 functioning as sacrificial layers are alternately laminated on a substrate W. The laminate 3 also includes a plurality of memory trenches 4 extending through the laminate 3 in a direction perpendicular to the surface of the substrate W. Fig. 2(a) is a partial enlarged view of a portion surrounded by A in the laminate in Fig. 1(a).

[0040] As shown in FIG. 3, the method for manufacturing a semiconductor device according to the present embodiment includes at least a self-assembled monolayer (hereinafter referred to as "SAM") forming 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 laminate 3. FIG. 3 is a flowchart showing an example of the overall flow of the method for manufacturing a semiconductor device according to the present embodiment.

[0041] <SAM Formation Step> The SAM forming step S1 is a step of selectively forming a SAM as a protective layer on the surface of the SiO2 layer 1 which is a layer to be protected. As shown in FIG. 3, the SAM forming step S1 includes at least a pretreatment step S101, a surface modification step S102, a first treatment liquid preparation step S103, a first contact step S104, a second treatment liquid preparation step S105, and a second contact step S106. Note that the SAM forming step S1 corresponds to the substrate processing method of the present invention.

[0042] 1.Pretreatment process The pretreatment step S101 is a step of physically adsorbing on the surface of the SiO2 layer 1 which is a layer to be protected and removing organic molecules that cover the surface of the SiO2 layer 1 in the form of particles or a thin film. Although this step is optional, it is preferable to perform this step from the viewpoint of improving the surface modification of the substrate W in the surface modification step S102 described later. Specifically, the pretreatment step S101 is performed by bringing a pretreatment liquid into contact with the surface of the substrate W.

[0043] The method of bringing the pretreatment liquid into contact 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] An example of a method for applying the pretreatment liquid to the surface of the substrate W is to supply the pretreatment liquid to the center of the surface of the substrate W while rotating the substrate W at a constant speed around its center as an axis. In this way, 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 setting the contact time of the pretreatment liquid to 1 minute or less, excessive etching of the surface portion of the SiO2 layer can be suppressed. Here, in this specification, the "film defect" of the SAM means that the molecules constituting the SAM are not directly chemically adsorbed to the surface of the substrate W (in this embodiment, the surface of the SiO2 layer 1), and the surface is exposed.

[0046] The temperature of the pretreatment liquid is not particularly limited and can be set as necessary, for example, to room temperature, etc. 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, a volume ratio of HF:deionized water (DIW)=1:100).

[0048] 2. Surface modification process (wet method) The surface modification step S102 is a step of modifying the surface of the SiO2 layer 1 shown in Fig. 4(a) to modify an area where chemical adsorption by the first molecule, which can form a SAM, is difficult, into an area where chemical adsorption by the first molecule is possible. Also, in the area where the first molecule can be chemically adsorbed, it is a step of making it possible to chemically adsorb the first molecule at a higher density. Fig. 4(a) is an explanatory diagram conceptually showing the surface state of the SiO2 layer 1 before the surface modification.

[0049] When the surface of the SiO2 layer 1 is modified in the surface modification step S102, hydroxyl groups are provided to the surface so that the first molecule can be chemically adsorbed, as shown in Fig. 4(b). Fig. 4(b) is an explanatory diagram conceptually showing the surface state of the SiO2 layer 1 after the surface modification.

[0050] In this embodiment, the surface of the SiO2 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 of 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] Further, as a method of 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 center of the surface of the substrate W while the substrate W is rotated at a constant speed around its center 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 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 surface modification liquid, and a liquid film of the surface modification liquid is formed.

[0052] The surface modification liquid is not particularly limited as long as it can provide hydroxyl groups to the surface of the SiO2 layer 1. Specific examples of the surface modification liquid include an ammonia-hydrogen peroxide solution mixture (Standard Clean-1 (SC-1)) (volume ratio of ammonium water (NH3 concentration 28%): hydrogen peroxide solution (H2O2 concentration 30%): DIW = 1:4:20), ammonia water, a tetramethylammonium hydroxide aqueous solution, and a trimethyl-2-hydroxyethylammonium hydroxide aqueous solution. Among these alkaline solutions, an ammonia-hydrogen peroxide solution mixture is preferable from the viewpoint of providing hydroxyl groups well to the SiO2 layer.

[0053] The conditions for contacting the substrate W with the surface modification liquid are not particularly limited, but the time for which the substrate W is contacted 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 setting the contact time of the surface modification liquid to 10 minutes or more, it is possible to provide sufficient hydroxyl groups to the surface of the SiO2 layer 1. This reduces the area where the first molecules cannot be chemically adsorbed, and allows the first molecules to be chemically adsorbed at a high density on the surface of the SiO2 layer 1. As a result, the occurrence of film defects is suppressed, and a SAM with excellent density and protective performance can be efficiently formed in a short time.

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

[0055] In addition, when the surface modification step S102 is performed by a wet method, a cleaning step for removing the surface modification liquid and a drying step may be performed in sequence immediately after the surface modification step S102. The cleaning method in the cleaning step is not particularly limited, and examples thereof include a method of supplying a cleaning liquid to the surface of the substrate W and a method of immersing the substrate W in the cleaning liquid. Examples of the cleaning liquid include toluene, decane, and 1,3-bis(trifluoromethyl)benzene. These solvents can be used alone or in a mixture of two or more. The cleaning conditions such as the cleaning time and the temperature of the cleaning liquid are not particularly limited, and can be set appropriately as needed. The drying step is intended to remove the cleaning 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. The drying conditions such as the drying time and the drying temperature are not particularly limited, and can be set appropriately as needed.

[0056] 3. First processing solution preparation process The first treatment liquid preparation step S103 is a step of preparing a first treatment liquid containing a first molecule, for example. The first molecule contained in the first treatment liquid may have a functional group capable of dehydration condensation reaction with a hydroxyl group. When the first molecule has the functional group, a dehydration condensation reaction can be caused between the functional group and the hydroxyl group on the surface of the SiO2 layer 1, which is the layer to be protected. As a result, the first molecule can be directly chemically adsorbed on the surface of the SiO2 layer 1, which is the layer to be protected, to form a SAM. In the following, a case will be described in which the functional group capable of dehydration condensation reaction with a hydroxyl group is a hydroxyl group as the first molecule contained in the first treatment liquid.

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

[0058] Examples of the organic solvent that is the main solvent include ether solvents, aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, fluorine solvents, and ketone 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 solvent is not particularly limited, and examples thereof include 1,3-bis(trifluoromethyl)benzene. The ketone 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. Among the solvents exemplified above, aromatic hydrocarbon solvents are preferred from the viewpoint of affinity with water, and toluene is particularly preferred. In addition, the organic solvent that is the main solvent is preferably one that has a low solubility of water. This allows water to be well dispersed in the organic solvent. Examples of the organic solvent that has a low solubility of water include the above-mentioned toluene.

[0059] The amount of water added in the dispersion is preferably in the range of 50 ppm or more and 200 ppm or less, and more preferably in the range of 50 ppm or more and 150 ppm or less. By making the amount of water added 50 ppm or more, it is possible to prevent the introduction of hydroxyl groups (functional groups capable of dehydration condensation reaction with hydroxyl groups) into the first molecules from being insufficient in the hydrolysis reaction with the water. That is, at the stage of generating the first treatment liquid, a sufficient amount of the first molecules to which hydroxyl groups have been introduced can be present in the first treatment liquid. As a result, it is possible to suppress the occurrence of film defects and form a SAM with excellent density, even if the treatment liquid is not brought into contact with the substrate surface for a long time to form a dense SAM, as in the conventional substrate treatment method. On the other hand, by making the amount of water added 200 ppm or less, it is possible to suppress the first molecules having hydroxyl groups from excessively agglomerating with each other due to the dehydration condensation reaction. As a result, it is possible to suppress the decrease in density of the first molecules to be chemically adsorbed on the substrate surface and form a SAM with excellent density.

[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. By applying ultrasonic waves, it is possible to prevent the generation of a mixed liquid in which the organic solvent phase and the water phase are separated. The conditions for applying ultrasonic waves, specifically, for example, the application time, frequency, and sound wave intensity, are not particularly limited as long as the water is dispersed in the organic solvent, and can be set appropriately as needed. In addition, the method for applying ultrasonic waves is also not particularly limited, and examples thereof include a method of immersing an ultrasonic vibrator in the mixed liquid and vibrating the ultrasonic vibrator to apply ultrasonic waves.

[0061] The preparation of the dispersion liquid is preferably carried out in an atmosphere of an inert gas such as nitrogen gas, etc. If the preparation is carried out in an environment in which moisture is present in the atmosphere, the moisture in the atmosphere will dissolve in the mixed liquid (or the dispersion liquid), and as a result, a dispersion liquid with a predetermined moisture content cannot be obtained, 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 first treatment liquid containing a first molecule having a hydroxyl group. When the SAM-forming material is added to the dispersion and after the SAM-forming material is added to the dispersion, it is preferable to do so without applying ultrasonic waves. By not applying ultrasonic waves, the first treatment liquid can be generated so that the first molecules exist without agglomerating with each other. By generating the first treatment liquid so that the first molecules exist without agglomerating with each other, a SAM can be successfully formed in the first contact 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 a molecule capable of forming a SAM. In addition, the SAM-forming material is preferably one having high affinity (solubility) for the above-mentioned organic solvent. Specifically, the SAM-forming material is, for example, octadecyltrichlorosilane (C 18 H 37 SiCl3), decyltrichlorosilane (C 10 H 21 The organic silane compounds include trichlorosilyl groups as functional groups exhibiting hydrolysis reactivity.

[0064] The first molecule before being added to the first treatment liquid has a functional group exhibiting hydrolysis reactivity. Therefore, when the SAM-forming material is added to the dispersion liquid, the functional group undergoes a hydrolysis reaction with the water molecules uniformly dispersed in the dispersion liquid. As a result, the functional group exhibiting hydrolysis reactivity becomes a functional group capable of undergoing a dehydration condensation reaction with a hydroxyl group. For example, when the first molecule is octadecyltrichlorosilane, the following reaction occurs: C 18 H 37 SiCl3+ 3H2O → C 18 H 37 Si(OH)3+ 3HCl3 As a result, a first treatment liquid can be obtained in which the first molecules having hydroxyl groups are present without agglomeration. By preparing a first treatment liquid containing the first molecules having hydroxyl groups in advance, the hydrolysis reaction, which is the rate-limiting step in the SAM film formation process, can be omitted. As a result, it becomes possible to form a SAM film 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 with respect to the total mass of the first treatment liquid.

[0066] The first 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 first treatment liquid is preferably prepared in a stationary state. More specifically, when the SAM-forming material is added to the dispersion, it is not preferable to apply mechanical force such as stirring and shaking to the dispersion. When the SAM-forming material is added to the dispersion, if mechanical force such as stirring and shaking is applied to the dispersion, the first molecules may aggregate with each other. However, by preparing the first treatment liquid by adding the SAM-forming material to the dispersion in a stationary state, it is possible to further suppress the aggregation of the first molecules with each other and generate the first treatment liquid.

[0068] The water content in the first treatment liquid is preferably within a range of 50 ppm or more and 200 ppm or less, and more preferably within a range of 50 ppm or more and 150 ppm or less.

[0069] The first treatment liquid preparation step S103 can be carried out, for example, under normal temperature and pressure. In this specification, "normal pressure" refers to pressure near the standard atmospheric state (standard atmospheric pressure), and the standard atmospheric state refers to a temperature of approximately 25°C and an atmospheric pressure of approximately 101 kPa absolute. "Normal pressure" also includes a pressure that is slightly positive or negative with respect to the standard atmospheric pressure.

[0070] 4.First contact process The first contacting step S104 is a step of contacting a first processing liquid containing first molecules with the surface of the substrate W to form a SAM.

[0071] The method of contacting the first processing liquid with the substrate W is not particularly limited, and examples thereof include a method of applying the first processing liquid to the surface of the substrate W, a method of spraying the first processing liquid onto the surface of the substrate W, and a method of immersing the substrate W in the first processing liquid.

[0072] An example of a method for applying the first processing liquid to the surface of the substrate W is to supply the first processing 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. As a result, the first 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 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 first processing liquid, and a liquid film of the first processing liquid is formed.

[0073] The conditions for contacting the first processing liquid with the substrate W are not particularly limited. However, the first contact step S104 of this embodiment can shorten the contact time of the first processing liquid compared to the case of forming a SAM film by a conventional method. Specifically, the time required for the SAM formation step S1 (when the substrate W is immersed in the first processing liquid, the immersion time) can be appropriately set within the 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, type of solvent, etc.

[0074] Next, the SAM formation process will be described in more detail using an example in which the SAM-forming material is octadecyltrichlorosilane. As shown in Fig. 4(c), when the first processing liquid is supplied to the surface of the substrate W, first molecules 5 in which hydroxyl groups have been introduced into octadecyltrichlorosilane are dispersed in the first processing liquid at the beginning of the supply. Fig. 4(c) is an explanatory diagram showing how the first processing liquid is supplied to the surface of the SiO2 layer 1.

[0075] Here, hydroxyl groups are introduced to the surface of the SiO2 layer 1 by the above-mentioned surface modification step S102. Therefore, the first molecules 5 undergo a dehydration condensation reaction with the hydroxyl groups, as shown in FIG. 5(a). More specifically, the hydroxyl groups of the first molecules 5 and the hydroxyl groups on the surface of the SiO2 layer 1 undergo a dehydration condensation reaction to form siloxane bonds, and the first molecules 5 are chemically adsorbed to the surface of the SiO2 layer 1. The first molecules 5 exist in the first treatment liquid in a state in which they are inhibited from coagulating with each other. Therefore, the dehydration condensation reaction between the hydroxyl groups of the first molecules 5 and the hydroxyl groups on the surface of the SiO2 layer 1, which is the rate-determining step in the SAM film formation process, can be promoted. In addition, the first molecules 5 can be chemically adsorbed to the surface of the SiO2 layer 1 at a high density. Note that FIG. 5(a) is an explanatory diagram showing how the first molecules 5 are chemically adsorbed to the surface of the SiO2 layer 1.

[0076] Next, when the first molecules 5 are chemically adsorbed at a high density on the surface of the SiO2 layer 1, an island-like structure of the first molecules 5 appears on the surface. Furthermore, in each island, the first molecules 5 self-organize and grow (expand) due to hydrophobic and electrostatic interactions with each other, and finally form a SAM6 (see FIG. 5(b)). However, film defects 7 may occur in the SAM6 at the boundaries between adjacent islands where the first molecules 5 cannot enter, or in areas where the first molecules 5 are attached to the surface of the SiO2 layer 1 without being chemically adsorbed. FIG. 5(b) is an explanatory diagram showing how the first molecules 5 self-organize on the surface of the SiO2 layer 1 to form a SAM6.

[0077] 5. Second processing solution preparation process The second treatment liquid preparation step S105 is a step of generating a second treatment liquid containing a second molecule. The second molecule contained in the second treatment liquid has a functional group capable of undergoing a dehydration condensation reaction with a hydroxyl group, and can be directly chemically adsorbed onto the surface of the SiO2 layer 1 to reduce or repair film defects in the SAM.

[0078] The second treatment liquid can be prepared in the same manner as the first treatment liquid. In addition, the materials used for the first treatment liquid can be used as the materials for preparing the second treatment liquid without any restrictions.

[0079] Here, the second molecule contained in the second treatment liquid may be the same or different from the first molecule. The second molecule preferably has the same or shorter molecular chain length as the first molecule, and more preferably has a shorter molecular chain length than the first molecule. For example, when the first molecule is C 18 H 37 In the case of Si(OH)3, the second molecule is C 10 H 21 Compounds such as Si(OH)3, C3H7Si(OH)3, or CH3Si(OH)3 are preferred.

[0080] 6.Second contact process The second contacting step S106 is a step of contacting the surface of the substrate W after the first contacting step S104 with a second processing liquid containing second molecules, repairing film defects 7 occurring in the SAM 6, and densifying the SAM 6. The second contacting step S106 is performed at least once until the area ratio (%) of film defects in the SAM formed on the surface of the SiO2 layer 1 becomes equal to or less than an arbitrarily set threshold value. Here, the area ratio (%) of film defects in the SAM is defined by the following formula: Area ratio of film defects (%) = (total area of ​​film defects in any area of ​​the SAM) / (area of ​​any area of ​​the SAM) × 100

[0081] The threshold value of the area ratio (%) of the film defects is not particularly limited and can be set arbitrarily. The area ratio (%) of the film defects can be calculated, for example, as follows. That is, for example, an atomic force microscope (AFM) is used to obtain an observation image (AFM image) of an arbitrary region where the SAM6 is formed, and the observation image is binarized, and image processing is further performed to map the film defects 7. As a result, the region of the film defects 7 of the SAM6 is specified, the area of ​​the specified region of the film defects 7 of the SAM6 is calculated, and the ratio of the area to the total area in the observation image is calculated. In addition, in mapping the film defects 7, it is preferable to perform image processing so that defects from the surface of the SAM6 to a depth position not exceeding the film thickness of the SAM6 are mapped, taking into account the film thickness of the SAM6.

[0082] When the second contact step S106 is performed multiple times, the second molecule contained in the second processing solution may be changed for each step. In this case, it is preferable that the second molecule used in the earlier step has the same or longer molecular chain length as the second molecule used in the later step. For example, C 10 H 21 When Si(OH)3 is used, it is preferable to use a second molecule such as C3H7Si(OH)3 or CH3Si(OH)3 in the second contact step. As the second contact step is repeated, the second molecule is chemically adsorbed to the film defects 7 of the SAM 6, resulting in a reduction in the area of ​​the film defects 7. Therefore, in the subsequent step, using a second molecule with a short molecular chain length reduces or suppresses the inability to chemically adsorb to the surface of the SiO2 layer 1 due to steric hindrance, thereby further improving the denseness.

[0083] The method of contacting the second processing liquid with the substrate W is the same as that described in the first contact step S104. Therefore, a detailed description thereof will be omitted. In addition, the conditions for contacting the second processing liquid with the substrate W can be appropriately set depending on the type of the second processing liquid, etc.

[0084] When the SAM-forming material is octadecyltrichlorosilane, the surface of the SAM6 in the second contact step S106 is as shown in FIG. 5(c). FIG. 5(c) is an explanatory diagram showing how the second processing liquid is supplied to the surface of the SiO2 layer 1. That is, as shown in the figure, when the second processing liquid is supplied to the surface of the substrate W, the second molecules 8 are dispersed in the second processing liquid at the beginning of the supply. In the figure, the second molecules 8 are illustrated as trichloropropylsilane with hydroxyl groups introduced therein as an example. Here, the molecular chain length of the second molecules 8 is shorter than that of the first molecules 5' constituting the SAM6. Therefore, the second molecules 8 undergo a dehydration condensation reaction with the hydroxyl groups on the surface of the SiO2 layer 1, even in the region where the film defect 7 of the SAM6 occurs, without causing steric hindrance between the second molecules 8 and the first molecules 5' constituting the SAM6. As a result, the second molecules 8 form siloxane bonds with the hydroxyl groups and are chemically adsorbed to the surface of the SiO2 layer 1. As a result, the film defects 7 that occurred in the SAM 6 are repaired as shown in Fig. 6, and a SAM 6' having excellent densification and protective performance is formed. Note that Fig. 6 is an explanatory diagram showing the state of the SAM 6' after the densification treatment.

[0085] 7.Other processes Immediately after the first contact step S104 and the second contact step S106, a removing step and a drying step may be sequentially performed, respectively. This makes it possible to remove the first processing solution remaining on the surface of the SiO2 layer 1 after the first contact step S104 and the second processing solution remaining on the surface of the SiO2 layer 1 after the second contact step S106. As a result, it is possible to remove the surplus first molecules 5 and second molecules 8 that do not contribute to the formation of the SAM 6', more specifically, the first molecules 5 and second molecules 8 that are not chemically adsorbed on the surface of the SiO2 layer 1. As a result, it is possible to prevent a film made of the unadsorbed first molecules 5 and second molecules 8 from being formed on the SAM 6', and to form a good monolayer.

[0086] The removal step is a step of replacing the first processing liquid or the second processing liquid (hereinafter sometimes referred to as "first processing liquid, etc.") remaining on the surface of the SiO2 layer 1 with a removal liquid and removing it. The method of removing the first processing liquid, etc. from the surface of the SiO2 layer 1 is not particularly limited, and examples thereof 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.

[0087] An example of a method for applying the removing liquid to the surface of the substrate W is to supply the removing liquid to the center of the surface of the substrate W while rotating the substrate W at a constant speed around its center 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 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 first processing liquid and the like on the surface of the substrate W are 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.

[0088] The removal liquid is not particularly limited, but an organic solvent that dissolves the SAM-forming material and has low water solubility is preferred. If the removal liquid can dissolve the SAM-forming material, the excess first molecules 5 and second molecules 8 that do not contribute to the formation of the SAM can be effectively removed from the surface. More specific examples of the removal liquid include toluene, decane, and 1,3-bis(trifluoromethyl)benzene. These solvents can be used alone or in combination of two or more.

[0089] The drying step is intended 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. The drying conditions such as the drying time and drying temperature are not particularly limited as long as the removing liquid is removed, and can be set appropriately as needed.

[0090] As a result, in the SAM formation step S1, as shown in FIG. 6, a SAM 6' having excellent density and protective performance can be formed on the surface of the SiO2 layer 1. In this embodiment, a hydroxyl group is introduced in advance to the surface of the SiO2 layer 1 in the surface modification step S102, and then a SAM 6 is formed in the first contact step S104. Furthermore, a densification treatment is performed on the SAM 6 in the second contact step S106, thereby repairing film defects 7 occurring in the SAM 6. As a result, even if the treatment liquid is not kept in contact with the surface of the SiO2 layer 1 for a long time to form a dense film, 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.

[0091] In this embodiment, a rinsing step and another drying step may be performed immediately after the drying step. By performing the rinsing step, the removing liquid can be removed from the surface of the SiO2 layer 1. Also, by performing another drying step, the rinsing liquid used in the rinsing step can be removed.

[0092] The rinse liquid in the rinse step is not particularly limited, and may be, for example, DIW, etc. The method of supplying the rinse liquid to the surface of the substrate W is not particularly limited, and may be, for example, 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, a method of immersing the substrate W in the rinse liquid, etc.

[0093] An example of a method for applying the rinse liquid to the surface of the substrate W is to supply the rinse 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 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 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 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.

[0094] The other 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. The drying conditions such as the drying time and drying temperature are not particularly limited as long as the rinsing liquid is removed, and can be set appropriately as necessary.

[0095] <Etching process (single wafer type)> The etching step S2 is a step of selectively etching the SiN layer 2, which is a sacrificial layer and 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 and removing the SiN layer 2. In this step, the SAM 6' functions as a protective layer to protect the SiO2 layer 1. This makes it possible to effectively prevent the SiO2 layer 1 from being etched.

[0096] As a method for applying the etching liquid to the surface of the substrate W, for example, in the case of a single-wafer process, the etching liquid is supplied to the center of the surface of the substrate W while the substrate W is rotated at a constant speed around its center 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 diffused 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.

[0097] The etching liquid can be appropriately set 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, for example, an aqueous solution of phosphoric acid (H3PO4) or hydrofluoric acid (for example, HF:DIW=1:100 in volume ratio) can be used as the etching liquid. The concentration of the etching liquid can also be appropriately set in consideration of the constituent material of the layer to be etched, the etching rate, etc.

[0098] Furthermore, the etching temperature (that is, the temperature of the etching solution) and the etch rate for the layer to be etched can be appropriately set in consideration of the constituent material of the layer to be etched.

[0099] It is preferable to sequentially perform a rinsing step for removing 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. In addition, 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 the drying temperature are not particularly limited, and can be set appropriately as needed.

[0100] As a result, in the etching step S2, only the SiN layer 2 can be selectively removed as shown in FIG. 2(c). In addition, the SAM 6', which has excellent density and protective performance, covers and protects the surface of the SiO2 layer 1, so that the SiO2 layer 1 can be prevented from being etched and the etched silicon component can be prevented from precipitating and adhering to the surface of the SiO2 layer 1. Furthermore, the tolerance range of the silicon concentration contained in the etching solution such as phosphoric acid can be increased. FIG. 2(c) is a partial enlarged view of the portion surrounded by B in the laminate in FIG. 1(b), showing the state in which the SiN layer 2 has been etched.

[0101] [Substrate processing equipment (semiconductor manufacturing equipment)] 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.

[0102] The semiconductor manufacturing apparatus 100 of this embodiment is a single-wafer processing unit used to form a SAM and etch a layer to be etched, and includes, as shown in Fig. 7, a substrate holding unit 110 for holding a substrate W, a pretreatment liquid supply unit 120 for supplying a pretreatment liquid to the surface Wf of the substrate W, a surface modification liquid supply unit (surface modification unit) 130 for supplying a surface modification liquid to the surface Wf of the substrate W, a first treatment liquid supply unit 140 for supplying a first treatment liquid to the surface Wf of the substrate W, an ultrasonic wave application unit, a second treatment liquid supply unit 150 for supplying a second treatment liquid, an inert gas supply unit (not shown) for supplying an inert gas, an etching liquid supply unit 160, a chamber 170 which is a container for accommodating the substrate W, a splash prevention cup 180 for collecting the treatment liquid, a swivel drive unit 190 for independently swivel-driving the arms of each unit described later, and a control unit 300. The semiconductor manufacturing apparatus 100 may also include a carry-in / out unit (not shown) for carrying in or out the substrate W. 7 is an explanatory diagram showing a schematic configuration of a semiconductor manufacturing apparatus 100 according to this embodiment. In this figure, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationship of the illustrated objects. Here, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction.

[0103] <Substrate holding part> The substrate holding unit 110 is a means for holding the substrate W, and as shown in Fig. 7, holds and rotates the substrate W in a substantially horizontal position with the 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 in a substantially vertical direction is fixed to the center of the spin base 111. 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.

[0104] The chuck rotation mechanism 114 can rotate the rotation support shaft 112 around the rotation axis J1 by being driven by a chuck drive unit (not shown) of the control unit 300. This causes the spin base 111 attached to the upper end of the rotation support shaft 112 to rotate around 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.

[0105] 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. The number of chuck pins 116 to be provided is not particularly limited, but it is preferable to provide at least three or more in order to reliably 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 circumferential end face of the substrate W supported by the substrate support pin.

[0106] <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. 7, the pre-treatment liquid supply unit 120 includes a pre-treatment liquid storage unit 121, a nozzle 122, and an arm 123.

[0107] 8, the pretreatment liquid storage unit 121 includes a pressurizing unit 124 and a pretreatment liquid tank 125. Note that, Fig. 8 is an explanatory diagram showing a schematic configuration of the pretreatment liquid storage unit 121 in the pretreatment liquid supply unit 120.

[0108] 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.

[0109] The nitrogen gas supply pipe 124b is connected to the treatment liquid tank 125. In addition, 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.

[0110] 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 allowing the agitation blade to agitate the pretreatment liquid. As a result, the concentration and temperature of the pretreatment liquid in the pretreatment liquid tank 125 can be made uniform.

[0111] Furthermore, a discharge pipe 125a for supplying the pre-treatment liquid to the nozzle 122 is connected to the pre-treatment 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 pre-treatment liquid is pressure-fed to the nozzle 122 via the discharge pipe 125a.

[0112] The nozzle 122 is attached to the tip of an arm 123 that extends horizontally, and is disposed above the spin base 111 when discharging the pre-treatment 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.

[0113] <Surface modification liquid supply unit (surface modification unit)> The surface modification liquid supply unit 130 according to this embodiment is a means for supplying a surface modification liquid to the front surface Wf of the substrate W. As shown in FIG. 7, the surface modification liquid supply unit 130 includes a surface modification liquid storage unit 131, a nozzle 132, and an arm 133.

[0114] 9, 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. 9 is an explanatory diagram showing a schematic configuration of the surface modification liquid storage unit 131 in the surface modification liquid supply unit 130.

[0115] The pressurizing unit 134 includes a nitrogen gas supply source 134a which is a gas supply source for pressurizing the inside of 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.

[0116] The nitrogen gas supply pipe 134b is connected to the surface modification liquid tank 135. In addition, 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.

[0117] The surface-modifying liquid tank 135 may include an agitation unit that agitates the surface-modifying liquid in the surface-modifying liquid tank 135, and a temperature adjustment unit that adjusts the temperature of the surface-modifying liquid (neither is shown). The agitation unit may include a rotation unit that agitates the surface-modifying liquid in the surface-modifying 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 provided 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 allowing the agitation blade to agitate the surface-modifying liquid. As a result, the concentration and temperature of the surface-modifying liquid in the surface-modifying liquid tank 135 can be made uniform.

[0118] 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.

[0119] The nozzle 132 is attached to the tip of an arm 133 that extends horizontally, and is disposed 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 a control unit 300, and rotates the arm 133 according to an operation command from the control unit 300. As the arm 133 rotates, the nozzle 132 also moves.

[0120] <First processing liquid supply unit> The first processing liquid supply unit 140 according to this embodiment is a unit that supplies a first processing liquid to the front surface Wf of the substrate W. As shown in FIG. 7 , the first processing liquid supply unit 140 has a first processing liquid storage unit 141, a first nozzle 142, and a first arm 143.

[0121] 10, the first treatment liquid storage section 141 includes a first organic solvent supply section 144, a first water supply section 145, a first SAM-forming material supply section 146, a first treatment liquid tank 147, a first temperature adjustment section 148, and a first inert gas supply section 149. Note that, Fig. 10 is an explanatory diagram showing a schematic configuration of the first treatment liquid storage section 141 and an ultrasonic wave application section 191 in the first treatment liquid supply section 140.

[0122] The first organic solvent supply unit 144 includes a first organic solvent storage unit 144a for storing an organic solvent, a first organic solvent supply pipe 144b for supplying the organic solvent to the first processing liquid tank 147, and a first valve 144c provided in the middle of the first organic solvent supply pipe 144b. The first valve 144c is electrically connected to the control unit 300. This allows the opening and closing of the first valve 144c to be controlled by an operation command from the control unit 300. When the first valve 144c is opened by an operation command from the control unit 300, the organic solvent is supplied to the first processing liquid tank 147 through the first organic solvent supply pipe 144b. The organic solvent in the first organic solvent storage unit 144a is pressurized by a pressurizing means (not shown) and sent to the first organic solvent supply pipe 144b. The pressurizing means is not particularly limited, and a known means such as a pump can be used.

[0123] The first water supply unit 145 includes a first water storage unit 145a for storing water, a first water supply pipe 145b for supplying water to the first treatment liquid tank 147, and a first valve 145c provided in the middle of the first water supply pipe 145b. The first valve 145c is electrically connected to the control unit 300. This allows the first valve 145c to be opened and closed by an operation command from the control unit 300. When the first valve 145c is opened by an operation command from the control unit 300, water is supplied to the first treatment liquid tank 147 through the first water supply pipe 145b. The water in the first water storage unit 145a is pressurized by a pressurizing means (not shown) and sent to the first water supply pipe 145b. The pressurizing means is not particularly limited, and a known means such as a pump can be used.

[0124] The first SAM forming material supply unit 146 includes a first SAM forming material storage unit 146a for storing the SAM forming material, a first SAM forming material supply pipe 146b for supplying the SAM forming material to the first processing liquid tank 147, and a first valve 146c provided in the middle of the first SAM forming material supply pipe 146b. The first valve 146c is electrically connected to the control unit 300. This allows the opening and closing of the first valve 146c to be controlled by an operation command from the control unit 300. When the first valve 146c is opened by an operation command from the control unit 300, the SAM forming material is supplied to the first processing liquid tank 147 through the first SAM forming material supply pipe 146b. The SAM forming material in the first SAM forming material storage unit 146a is pressurized by a pressurizing means (not shown) and sent to the first SAM forming material supply pipe 146b. The pressurizing means is not particularly limited, and a known means such as a pump can be used.

[0125] The first processing liquid tank 147 mixes the organic solvent supplied from the first organic solvent supply unit 144 with the water supplied from the first water supply unit 145, and generates a dispersion in which water is uniformly dispersed in the organic solvent by applying ultrasonic waves to the resulting mixture with the ultrasonic application unit 191. Alternatively, the dispersion can be generated by applying ultrasonic waves with the ultrasonic application unit 191 while mixing the organic solvent supplied from the first organic solvent supply unit 144 with the water supplied from the first water supply unit 145. Furthermore, a processing liquid can be generated by supplying a SAM-forming material from the first SAM-forming material supply unit 146 while storing the generated dispersion.

[0126] The first processing liquid tank 147 may include a first temperature adjustment unit 148 for adjusting the temperature of the dispersion liquid and the first processing liquid stored therein. The first temperature adjustment unit 148 is electrically connected to the control unit 300. The control unit 300 issues an operation command to the first temperature adjustment unit 148, thereby making it possible to control the liquid temperature of the dispersion liquid when the dispersion liquid is generated. 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.

[0127] The first inert gas supply unit 149 includes a first inert gas supply source 149a which is a supply source for supplying an inert gas into the first processing liquid tank 147, a pump (not shown) for pressurizing the inert gas, a first inert gas supply pipe 149b, and a first valve 149c provided midway along the first inert gas supply pipe 149b.

[0128] The first inert gas supply pipe 149b is connected to the first processing liquid tank 147. The first valve 149c is electrically connected to the control unit 300, and the opening and closing of the first 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 first processing liquid tank 147. This allows the generation of the dispersion liquid and the first processing liquid to be performed under an atmosphere of the inert gas. The inert gas is not particularly limited, and examples thereof include nitrogen gas.

[0129] Further, a first discharge pipe 147a for supplying the first processing liquid to the first nozzle 142 is connected to the first processing liquid tank 147. A first discharge valve 147b is provided in the middle of the first discharge pipe 147a. The first discharge valve 147b is also electrically connected to the control unit 300. This allows the opening and closing of the first discharge valve 147b to be controlled by an operation command from the control unit 300. When the first discharge valve 147b and the first valve 149c are opened and the first valves 144c, 145c, and 146c are closed by an operation command from the control unit 300, the first processing liquid is pressure-fed to the first nozzle 142 via the first discharge pipe 147a.

[0130] The first nozzle 142 is attached to the tip of a first arm 143 that extends horizontally, and is disposed above the spin base 111 when discharging the first processing liquid. The first 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 first arm 143 in response to an operation command from the control unit 300. As the first arm 143 rotates, the first nozzle 142 also moves.

[0131] <Second processing liquid supply unit> The second processing liquid supply unit 150 according to this embodiment is a unit that supplies a second processing liquid to the front surface Wf of the substrate W. As shown in FIG. 7 , the second processing liquid supply unit 150 has a second processing liquid storage unit 151, a second nozzle 152, and a second arm 153.

[0132] The second processing liquid storage section 151 may have the same configuration as the first processing liquid storage section 141 shown in Fig. 10. Therefore, a detailed description thereof will be omitted.

[0133] The second nozzle 152 is attached to the tip of a second arm 153 that extends horizontally, and is disposed above the spin base 111 when discharging the second processing liquid. The second 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 second arm 153 in response to an operation command from the control unit 300. As the second arm 153 rotates, the second nozzle 152 also moves.

[0134] <Ultrasonic application unit> 10, the ultrasonic wave application unit 191 is a unit that applies ultrasonic waves when a dispersion liquid is generated in the first treatment liquid tank 147 of the first treatment liquid supply unit 140. The ultrasonic wave application unit 191 is also a unit that applies ultrasonic waves when a dispersion liquid is generated in the second treatment liquid tank of the second treatment liquid supply unit 150. The ultrasonic wave application unit 191 is electrically connected to the control unit 300, and the application of ultrasonic waves can be controlled by an operation command from the control unit 300.

[0135] The ultrasonic wave application unit 191 includes at least an ultrasonic vibrator provided in the first processing liquid tank 147 (in the second processing liquid tank in the second processing liquid storage unit 151), and an oscillator that applies a drive voltage to the ultrasonic vibrator (both not shown). An example of the ultrasonic vibrator 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, and the drive voltage is applied to the piezoelectric body. The piezoelectric body to which the drive voltage is applied vibrates by alternately repeating contraction and expansion 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 first processing liquid tank 147 or the second processing liquid tank.

[0136] <Removal liquid supply section> The removing liquid supplying unit according to this embodiment is a unit that supplies the removing liquid to the front surface Wf of the substrate W. This removing liquid supplying unit has a removing liquid storage unit, a nozzle, and an arm (none of which are shown).

[0137] The removing liquid reservoir has a function of supplying the removing liquid to the nozzle, and includes a pressurizing unit and a removing liquid tank.

[0138] The pressurizing unit includes a nitrogen gas supply source that is a supply source of gas that pressurizes the inside of the removal liquid tank, a pump that pressurizes the nitrogen gas, a nitrogen gas supply pipe, and a valve provided midway along the nitrogen gas supply pipe.

[0139] The nitrogen gas supply pipe is connected to the removal liquid tank. The valve is also electrically connected to the control unit 300, and the opening and closing of the valve 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, nitrogen gas can be supplied to the removal liquid tank.

[0140] The removal liquid tank may include an agitation unit that agitates the removal liquid in the removal liquid tank, and a temperature adjustment unit that adjusts the temperature of the removal liquid (neither is shown). Examples of the agitation unit include a rotation unit that agitates the removal liquid in the removal liquid tank, 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 allowing the agitation blade to agitate the removal liquid. As a result, the concentration and temperature of the removal liquid can be made uniform in the removal liquid tank.

[0141] Furthermore, a discharge pipe for supplying the removal liquid to the nozzle is connected to the removal liquid tank. A discharge valve is provided midway along the discharge pipe. This discharge valve is electrically connected to the control unit 300. This allows the opening and closing of the discharge valve to be controlled by an operation command from the control unit 300. When the discharge valve is opened by an operation command from the control unit 300, the removal liquid is pressure-fed to the nozzle via the discharge pipe.

[0142] The nozzle is attached to the tip of a horizontally extending arm, and is positioned above the spin base 111 when discharging the removal liquid. 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 according to an operation command from the control unit 300. The nozzle also moves as the arm rotates.

[0143] <Inert gas supply section> The inert gas supply unit is a means for supplying 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).

[0144] 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 adjustment unit for adjusting the temperature of the inert gas stored in the inert gas tank, and a pipe. The inert gas stored in the inert gas tank can be, for example, nitrogen gas.

[0145] The inert gas temperature adjustment 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 according to an operation command from the control unit 300. The inert gas temperature adjustment unit is not particularly limited, and any known temperature adjustment mechanism such as a Peltier element or a pipe through which temperature-adjusted water flows can be used.

[0146] The inert gas storage section is connected to the nozzle through 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 compressing and storing the inert gas in the inert gas tank, in addition to pressurization by a pump or the like.

[0147] 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 a nozzle through a pipe to the front surface Wf of the substrate W.

[0148] 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 according to an operation command from the control unit 300. The nozzle also moves as the arm rotates.

[0149] <Etching solution supply unit> The etching liquid supply unit 160 is a means for supplying an etching liquid to the front surface Wf of the substrate W. The etching liquid supply unit 160 has an etching liquid storage unit 161, a nozzle 162, and an arm 163, as shown in FIG.

[0150] 11, the etching liquid storage unit 161 includes at least an etching liquid tank 164, a temperature regulator 165, a liquid delivery 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.

[0151] The etching solution tank 164 may include an agitation unit (not shown) that agitates the etching solution in the etching solution tank 164. The agitation unit may 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 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 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.

[0152] The etching solution tank 164 is provided with a mixer 168 capable of mixing an etching solution with a chemical and DIW from an external supply source (not shown) to prepare an etching solution of a predetermined concentration. The chemical is a solute that functions as an etchant. Examples of the chemical include the aforementioned phosphoric acid and hydrogen fluoride.

[0153] Further, the etching solution tank 164 is connected to a discharge pipe 169 for supplying the etching solution to the nozzle 162. A temperature regulator 165, a liquid delivery pump 166, and a particle filter 167 are sequentially interposed in the middle of the discharge pipe 169 from upstream to downstream. The temperature regulator 165 and the liquid delivery pump 166 are electrically connected to the control unit 300. This allows the temperature of the etching solution to be supplied to the nozzle 162 to be controlled by an operation command from the control unit 300. Furthermore, when the liquid delivery pump 166 is controlled by an operation command from the control unit 300, the etching solution can be pressure-fed to the nozzle 162 through the discharge pipe 169. The particle filter 167 can remove foreign matter such as particles in the etching solution.

[0154] The nozzle 162 is attached to the tip of an arm 163 that extends horizontally, and is positioned above the spin base 111 when discharging the etching liquid. 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 according to an operation command from the control unit 300. As the arm 163 rotates, the nozzle 162 also moves.

[0155] <Shatterproof cup> The splash prevention cup 180 is provided so as to surround the spin base 111. The splash prevention cup 180 is connected to a lift drive mechanism (not shown) and can be raised and lowered in the vertical direction. When supplying a processing liquid or the like to the front surface Wf of the substrate W, the splash prevention cup 180 is positioned at a predetermined position by the lift drive mechanism and surrounds the substrate W held by the chuck pins 116 from a lateral position. This makes it possible to collect the processing liquid or the like splashed from the substrate W or the spin base 111.

[0156] <Control Unit> The control unit 300 is electrically connected to each part of the semiconductor manufacturing apparatus and controls the operation of each part. The control unit 300 is composed of a computer having an arithmetic unit and a storage unit. As the arithmetic unit, a CPU that performs various arithmetic processes is used. Further, the storage unit includes a read-only memory (ROM) that stores a substrate processing program and an etching processing program, a random access memory (RAM) that stores various information and is readable and writable, and a magnetic disk that stores control software, data, and the like. The magnetic disk stores in advance processing conditions including generation (mixing) conditions of the dispersion liquid and the processing liquid; supply conditions of the pretreatment liquid, the surface modification liquid, the first processing liquid, the second processing liquid, the removal liquid, the inert gas, and the etching liquid; application conditions of ultrasonic waves; rinsing conditions; drying conditions; processing conditions of the first contact step and the second contact step; and etching conditions, etc. The CPU reads the processing conditions into the RAM and controls each part of the semiconductor manufacturing apparatus according to the content thereof.

[0157] (Second Embodiment) The second embodiment of the present invention will be described below. This embodiment is different from the first embodiment in that the surface modification step is performed by a dry method using ultraviolet irradiation. Also, it is different in that the etching step is performed in a batch manner instead of a single-wafer type. Even with such a configuration, a SAM having a high film density, excellent denseness, and good suppression or reduction of film defects, and excellent protection performance can be efficiently formed on the substrate surface in a shorter time than the conventional film formation method.

[0158] [Substrate Processing Method (Manufacturing Method of Semiconductor Device)] The substrate processing method (manufacturing method of semiconductor device) according to this embodiment will be described below. FIG. 12 is a flowchart showing an example of the overall flow of the substrate processing method according to the second embodiment of the present invention.

[0159] [SAM Formation Step] 12, the pretreatment step S101, the first treatment liquid preparation step S103, the first contact step S104, the second treatment liquid preparation step S105, and the second contact step S106 are the same as those in the first embodiment, and therefore the detailed description of these steps will be omitted.

[0160] 1. Surface modification process (dry method) The surface modification step S102' is a step of modifying the surface of the SiO2 layer 1 so that the area where chemisorption of SAM molecules is difficult is changed to an area where chemisorption of SAM molecules is possible, similar to the surface modification step S102 in the first embodiment. Also, the surface modification step is a step of modifying the surface so that the area where chemisorption of SAM molecules is possible at a high density is changed.

[0161] In this embodiment, the surface of the SiO2 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 not particularly limited as long as hydroxyl groups can be introduced to the surface of the SiO2 layer 1 to an extent that the first molecule 5 and the second molecule 8 can be chemically adsorbed. In addition, the ultraviolet irradiation is performed in an atmosphere containing oxygen atoms, such as air.

[0162] <Etching process (batch type)> 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.

[0163] The method of immersing the substrate W in the etching solution is, for example, performed with the substrate W in an upright position. Here, the "upright position" refers to a position in which the surface of the substrate W is aligned in a direction substantially perpendicular to a horizontal plane, and includes a vertical position. The etching solution may be the same as that described in the first embodiment. In addition, 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.

[0164] [Substrate processing equipment (semiconductor manufacturing equipment)] 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.

[0165] The semiconductor manufacturing apparatus of this embodiment differs from the substrate processing apparatus of the first embodiment in that it is equipped with 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.

[0166] <Substrate processing unit> As shown in FIG. 13, the substrate processing unit 200 of this embodiment is different from the semiconductor manufacturing apparatus 100 of the first embodiment in that an ultraviolet ray irradiation unit 210 is provided as a surface modification unit instead of a surface modification liquid supply unit. FIG. 13 is an explanatory diagram showing a schematic configuration of the substrate processing unit according to this embodiment. In this figure, some of the configuration common to the semiconductor manufacturing apparatus 100 of the first embodiment is omitted. In this figure, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationship of the illustrated objects. Here, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction.

[0167] The ultraviolet ray irradiation unit 210 is disposed above the substrate holding unit 110 (in the direction indicated by the arrow Z in FIG. 13 ) 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 inside the chamber 170. The ultraviolet ray irradiation unit 210 includes at least a plurality of light source units 211 and quartz glass 212.

[0168] The light source section 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 sections 211 are also arranged in the direction indicated by the arrow X so as to be equally spaced from one another. However, the light source section 211 of the present invention is not limited to this embodiment. For example, the light source section 211 may be ring-shaped light source sections having different diameters arranged concentrically. The light source section may also be a point light source. In this case, it is preferable that the multiple light source sections are arranged so as to be equally spaced from one another in a plane.

[0169] The type of the 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 light source units of different types are used as the light source unit 211, they can be arranged with different peak wavelengths, light intensities, etc.

[0170] 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 provided so as to be parallel to the horizontal direction. The quartz glass 212 has optical transparency, heat resistance, and corrosion resistance to ultraviolet rays, and allows the ultraviolet rays irradiated from the light source unit 211 to pass through, enabling the ultraviolet rays to be irradiated onto the surface Wf of the substrate W. Furthermore, the quartz glass 212 can protect the light source unit 211 from the atmosphere in the chamber 170.

[0171] <Etching processing unit> The etching processing unit of this embodiment is a batch-type processing unit used for etching a layer to be etched, and performs an etching step S2' on a substrate W on which a SAM has been formed in the substrate processing unit. As shown in Figs. 14 and 15, the etching processing unit at least includes 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 a plurality of substrates W on which a SAM has been formed in this embodiment are immersed in an etching solution.

[0172] The substrate transport unit transports the substrate 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 substrate W. The tip of the articulated robot includes a transport arm capable of loading the substrates W all at once in a horizontal position.

[0173] As shown in FIG. 14, the lifter 220 includes a flat back plate 221, a plurality (three) of holding bars 222, and a lifting mechanism (not shown). The back plate 221 stands upright, and at its lower end, the holding bars 222 extend in one direction so as to be perpendicular to the back plate 221. The holding bars 222 are provided with a plurality of grooves 223 arranged in the extending direction. The plurality of grooves 223 are arranged at equal intervals and spaced apart from one another. Furthermore, each groove 223 extends in a direction perpendicular to the extending direction of the holding bar 222, and a plurality of substrates W can be fitted in the holding bars 222 in an upright position. As a result, the holding bars 222 can abut against and support the group of substrates W from below in an upright position, and hold them collectively. The number of holding bars 222 is not particularly limited as long as it is plural. Furthermore, the number of grooves 223 provided in the holding rod 222 is not particularly limited and may be set appropriately depending on the number of substrates W to be held. Furthermore, the lifting mechanism can raise or lower the lifter 220 in the Z direction shown in Fig. 15. This allows the lifter 220, which is collectively holding the group of substrates W, to be moved into or removed from the processing tank 230.

[0174] 15, the processing tank 230 includes an injection pipe 231 for supplying an etching solution into the processing tank 230, an inner tank 232 for storing the etching solution, and an outer tank 233 provided on the periphery of the upper opening of the inner tank 232. The injection pipe 231 is provided on 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 enables the etching solution overflowing 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, for example, via a discharge pipe 169.

[0175] (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, the etching process of the SiN2 layer is performed in a single-wafer manner, but the etching process may be performed in a batch manner as described in the second embodiment. In the first embodiment, the surface modification process is performed in a wet manner, but the surface modification process may be performed in a dry manner using ultraviolet light irradiation as described in the second embodiment. Even in these embodiments, a SAM having high film density and excellent compactness, in which the occurrence of film defects is well suppressed or reduced, and excellent protective performance can be efficiently formed on the substrate surface in a shorter time than in the conventional film formation method. EXAMPLES

[0176] Preferred examples of the present invention are described in detail below. However, the materials, amounts, conditions, etc. described in the examples are not intended to limit the scope of the present invention unless otherwise specified.

[0177] Example 1 A substrate with a SiO2 film (thickness 100 nm) formed on its surface was prepared and immersed in a hydrogen fluoride aqueous solution (pretreatment liquid) for 1 minute (pretreatment step). The hydrogen fluoride aqueous solution used had a volume ratio of hydrogen fluoride to DIW of 1:100.

[0178] Next, the substrate was removed from the hydrogen fluoride solution and immersed in a surface modification liquid for 10 minutes (surface modification process). The surface modification liquid used was SC-1 (volume ratio: ammonium water (NH3 concentration 28%): hydrogen peroxide water (H2O2 concentration 30%): DIW = 1:4:20).

[0179] On the other hand, a first treatment liquid was also prepared separately from the surface modification process of the substrate. That is, in a sealed container in a stationary state, 100 ppm of water was added to toluene as an organic solvent under conditions of a temperature of 23°C and normal pressure. Furthermore, ultrasonic waves were applied to the mixed liquid of toluene and water in a stationary state for 30 minutes. In this way, a dispersion liquid in which water was uniformly dispersed in toluene as the main solvent was prepared. The ultrasonic application conditions were a frequency of 45 Hz. Next, octadecyltrichlorosilane (C) as a SAM-forming material was added to the dispersion liquid in a stationary state. 18 H 37 SiCl3) was added under conditions of a temperature of 23°C and normal pressure to prepare a first treatment liquid (first treatment liquid preparation step). The content (concentration) of octadecyltrichlorosilane was 5 mass% with respect to the total mass of the first treatment liquid.

[0180] Next, the substrate removed from the surface modification liquid was immersed in the first treatment liquid for 5 minutes to form a SAM (approximately 1 nm thick) on the SiO2 film surface of the substrate (first contact step). Next, the substrate removed from the first treatment liquid was immersed in toluene as a removal liquid for 1 minute to remove unadsorbed SAM-forming material remaining on the substrate surface (removal step). Furthermore, the surface on which the SAM was formed of the substrate removed from the toluene was dried by blowing nitrogen gas onto it (drying step). The temperature of the nitrogen gas was room temperature, and the drying time was 1 minute.

[0181] Next, the substrate after the drying step was immersed in a second treatment liquid for 5 minutes to perform a densification treatment of the SAM (second contact step). The second treatment liquid used was the same as the first treatment liquid. Next, the substrate removed from the second treatment liquid was immersed in toluene as a removal liquid for 1 minute to remove the unadsorbed SAM-forming material remaining on the surface of the substrate (removal step). Furthermore, the surface on which the SAM was formed of the substrate removed from the toluene was dried by blowing nitrogen gas onto it (drying step). The temperature of the nitrogen gas was room temperature, and the drying time was 1 minute.

[0182] Next, the obtained sample was subjected to an etching process. Specifically, the substrate was immersed in an etching solution, and the area on the substrate surface that was not protected by the SAM was etched. The etching conditions were set to 195 seconds for immersion time in the etching solution (etching process time) so that the amount of SiO2 etched was about 10 nm. An aqueous hydrogen fluoride solution was used as the etching solution, and the volume ratio of hydrogen fluoride to DIW was hydrogen fluoride:DIW=1:100.

[0183] Next, the substrate was removed from the etching solution and immersed in DIW, and then removed from the DIW (rinsing process with DIW). The etched surface was then dried by spraying nitrogen gas on it (drying process). The temperature of the nitrogen gas was room temperature.

[0184] Example 2 In this example, trichloropropylsilane (C3H7SiCl3) was used as the SAM-forming material of the second treatment liquid. Except for that, samples were prepared in the same manner as in Example 1, and the obtained samples were subjected to an etching treatment.

[0185] Example 3 In this example, trichloromethylsilane (CH3SiCl3) was used as the SAM-forming material of the second treatment liquid. Except for that, samples were prepared in the same manner as in Example 1, and the obtained samples were subjected to an etching treatment.

[0186] Example 4 In this example, the cycle of the second contact step and the subsequent removal and drying steps was repeated twice. In the second second contact step, decyltrichlorosilane (C 10 H 21 Other than that, a sample was prepared in the same manner as in Example 1, and the obtained sample was subjected to an etching treatment.

[0187] Example 5 In this example, the cycle of the second contact step and the subsequent removal and drying steps was repeated twice. In the second second contact step, trichloropropylsilane (C3H7SiCl3) was used as the SAM-forming material of the second treatment liquid. Other than that, samples were prepared in the same manner as in Example 1, and the obtained samples were subjected to an etching treatment.

[0188] Example 6 In this example, the cycle of the second contact step and the subsequent removal and drying steps was repeated twice. In the second second contact step, trichloromethylsilane (CH3SiCl3) was used as the SAM-forming material of the second treatment liquid. Other than that, samples were prepared in the same manner as in Example 1, and the obtained samples were subjected to an etching treatment.

[0189] Comparative Example 1 In this comparative example, the second contact step and the subsequent removing and drying steps were not performed. 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.

[0190] (SAM compactness evaluation) For each of the samples according to Examples 1 to 6 and Comparative Example 1, the area ratio (%) of the film defects in the SAM was calculated to evaluate the denseness of the SAM.

[0191] That is, the SAM of each sample was imaged using an atomic force microscope (AFM) (trade name: Dimension Icon, manufactured by Bruker Japan Co., Ltd.), and an observation image (AFM image) of 500 nm square was obtained. Next, each obtained observation image was binarized, and then image processing was performed to map the film defects, and the site (region) of the film defect of the SAM was identified. In order to identify the site (region) of the film defect of the SAM by mapping, image processing was performed so that defects located at a depth of less than 1 nm from the SAM surface were mapped, taking into consideration that the film thickness of the SAM was about 1 nm. This ensured that the site (region) at a depth of more than 1 nm from the SAM surface, more specifically, the etched site, was not mapped as the region of the film defect of the SAM and was not included in the area. Next, the area of ​​the film defect region of the SAM identified by image processing was calculated, and the ratio to the area of ​​the entire region in the observation image was calculated. The results are shown in Table 1.

[0192] (result) As can be seen from Table 1, in Examples 1 to 6 in which the densification treatment was performed by the second contact step, the area ratio of the SAM film defects was reduced compared to Comparative Example 1 in which the second contact step was not performed, and it was confirmed that all of them had good densification. Furthermore, in Examples 2 and 3, the area ratio of the SAM film defects was reduced more than in Example 1 by using a SAM-forming material in the second treatment liquid used in the second contact step that had a shorter molecular chain length than the SAM-forming material in the first treatment liquid. Furthermore, in Examples 4 to 6, the cycle of the second contact step and the subsequent removal step and drying step was repeated twice, so that the area ratio of the SAM film defects was further reduced more than in Examples 2 and 3.

[0193] In addition, from the results of each of these Examples, it is understood that when the threshold value of the area ratio (%) of the film defects of the SAM is set to, for example, 15% or less, the second molecule used in the second contact step should be at least the same type as that used in the first contact step, as in Example 1. In addition, when the threshold value is set to, for example, 10% or less, it is understood that the second molecule used in the second contact step should have a shorter molecular chain length than that used in the first contact step, as in Examples 2 and 3, or the second contact step should be performed multiple times, and the second molecule used in the second contact step should have a shorter molecular chain length than that used in the first second contact step, as in Example 4. Furthermore, it is understood that when the threshold value is set to 5% or less, it is understood that the second contact step should be performed multiple times, and the second molecule used in the second contact step should have a shorter molecular chain length than that used in the first second contact step, as in Examples 5 and 6.

[0194] [Table 1] [Explanation of symbols]

[0195] 1 SiO2 layer (protected layer) 2 SiN layer (layer to be etched) 3. Laminate 4. Memory Trench 5 The first molecule 6 SAM (Self-assembled monolayer) 7. Membrane Defects 8 The second molecule 100 Semiconductor manufacturing equipment 110 Board holding part 120 Pre-treatment liquid supply unit 121 Pretreatment liquid storage section 130 Surface modification liquid supply unit 131 Surface modification liquid storage section 140 First processing liquid supply unit 141 First processing liquid storage section 150 Second processing liquid supply unit 151 Second processing liquid storage section 160 Etching solution supply unit 161 Etching solution storage section 190 Swivel drive unit 200 Substrate Processing Unit 210 Ultraviolet irradiation unit 220 Lifter 230 Treatment tank 231 Injection tube 232 Inner tank 233 Outer tank 300 Control section S1 SAM (self-assembled monolayer) formation process S2, S2' Etching process S101 Pretreatment process S102 Surface modification process S103: First processing solution preparation step S104 1st contact process S105 Second processing liquid preparation process S106 2nd contact process W substrate Surface of Wf substrate

Claims

1. A substrate processing method for forming a self-assembled monolayer on a surface of a substrate, comprising the steps of: a surface modification step of modifying the surface of the substrate so as to enable the formation of the self-assembled monolayer; a first contacting step of contacting a first treatment liquid containing first molecules capable of forming the self-assembled monolayer with the surface of the substrate after the surface modification step, thereby forming the self-assembled monolayer; a second contacting step of contacting the surface of the substrate after the first contacting step with a second treatment liquid containing second molecules of the same or different type as the first molecules, thereby chemically adsorbing the second molecules in an area where the self-assembled monolayer is not formed; Including, the second contact step is performed at least once until an area ratio (%) of film defects in the self-assembled monolayer formed on the surface of the substrate becomes equal to or less than an arbitrarily set threshold value; A method for processing a substrate.

2. The method of claim 1 , wherein the second molecule has a molecular chain length that is the same as or shorter than that of the first molecule.

3. 2. The substrate processing method according to claim 1, wherein when the second contact step is performed multiple times, the second molecule used in an earlier step has a molecular chain length that is the same as or longer than the second molecule used in a later step.

4. the first molecule and the second molecule have a functional group capable of undergoing a dehydration condensation reaction with a hydroxyl group, the surface modification step is a step of providing the hydroxyl group to the surface of the substrate, 2. The substrate processing method according to claim 1, wherein the first contact step and the second contact step are steps of chemically adsorbing the first molecule or the second molecule to the surface of the substrate by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the substrate.

5. The surface modification step includes:

5. The substrate processing method according to claim 4, wherein the hydroxyl groups are provided to the surface of the substrate by contacting the surface of the substrate with a surface modification liquid consisting of an alkaline solution, or by irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms.

6. 1. A method for manufacturing a semiconductor device, comprising processing a substrate having a laminate provided on a surface thereof, the method comprising: The laminate includes a layer to be protected from etching and a layer to be etched that are alternately laminated, selectively forming a self-assembled monolayer on at least a surface of the layer to be protected; selectively etching the layer to be etched using the self-assembled monolayer as a protective layer; Including, The step of forming a self-assembled monolayer includes: a surface modification step of modifying the surface of the protective layer to enable the formation of the self-assembled monolayer; a first contacting step of contacting a first treatment liquid containing first molecules capable of forming the self-assembled monolayer with the surface of the protective layer after the surface modification step to form the self-assembled monolayer; a second contacting step of contacting the surface of the substrate after the first contacting step with a second treatment liquid containing second molecules of the same or different type as the first molecules, thereby chemically adsorbing the second molecules in an area where the self-assembled monolayer is not formed; Including, the second contact step is performed at least once until a defect area ratio (%) of the self-assembled monolayer formed on the surface of the protective layer becomes equal to or less than an arbitrarily set threshold value; A method for manufacturing a semiconductor device.

7. The method for manufacturing a semiconductor device according to claim 6 , wherein the second molecule has a molecular chain length equal to or shorter than that of the first molecule.

8. 7. The method for manufacturing a semiconductor device according to claim 6, wherein when the second contact step is performed multiple times, the second molecule used in an earlier step has a molecular chain length equal to or longer than that of the second molecule used in a later step.

9. the first molecule and the second molecule have a functional group capable of undergoing a dehydration condensation reaction with a hydroxyl group, the surface modification step is a step of providing the hydroxyl group to a surface of the protective layer, 7. The method for manufacturing a semiconductor device according to claim 6, wherein the first contact step and the second contact step are steps for chemically adsorbing the first molecule or the second molecule to the surface of the protected layer by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the protected layer.

10. The surface modification step includes:

10. The method for manufacturing a semiconductor device according to claim 9, wherein the hydroxyl groups are provided to the surface of the substrate by contacting the surface of the substrate with a surface modification liquid consisting of an alkaline solution, or by irradiating the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms.

11. A substrate processing apparatus for forming a self-assembled monolayer on a surface of a substrate, comprising: a surface modification unit that performs surface modification on the surface of the substrate to enable the formation of the self-assembled monolayer; a first processing liquid supply unit that supplies a first processing liquid containing first molecules capable of forming the self-assembled monolayer to the surface of the substrate that has been surface-modified by the surface modification unit, thereby forming the self-assembled monolayer; a second processing liquid supply unit that supplies a second processing liquid containing second molecules of the same kind or different kind as the first molecules to the surface of the substrate on which the self-assembled monolayer is formed, thereby chemically adsorbing the second molecules in an area where the self-assembled monolayer is not formed; Equipped with the second processing liquid supply unit supplies the second processing liquid at least once until an area ratio (%) of film defects of the self-assembled monolayer formed on the surface of the substrate becomes equal to or less than an arbitrarily set threshold value; Substrate processing equipment.

12. The substrate processing apparatus of claim 11 , wherein the second molecules have a molecular chain length that is the same as or shorter than that of the first molecules.

13. 12. The substrate processing apparatus of claim 11, wherein when the second processing liquid supply unit supplies the second processing liquid to the surface of the substrate multiple times, the second molecules contained in the second processing liquid supplied earlier have a molecular chain length that is the same as or longer than that of the second molecules contained in the second processing liquid supplied later.

14. the first molecule and the second molecule have a functional group capable of undergoing a dehydration condensation reaction with a hydroxyl group, the surface modification unit performs the surface modification by providing the hydroxyl group to the surface of the substrate, 12. The substrate processing apparatus of claim 11, wherein the first processing liquid supply unit and the second processing liquid supply unit chemically adsorb the first molecule or the second molecule to the surface of the substrate by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the substrate.

15. The surface modification portion is a surface modifying liquid supply unit that provides a hydroxyl group to the surface of the substrate by supplying a surface modifying liquid made of an alkaline solution to the surface of the substrate; 15. The substrate processing apparatus according to claim 14, further comprising an ultraviolet irradiating section that irradiates the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms, thereby providing hydroxyl groups to the surface of the substrate.

16. A semiconductor manufacturing apparatus for processing a substrate having a laminate on a surface thereof, comprising: The laminate includes a layer to be protected from etching and a layer to be etched which are alternately laminated, a surface modification unit that performs surface modification on the surface of the protective layer to enable the formation of a self-assembled monolayer; a first treatment liquid supply unit that supplies a first treatment liquid containing first molecules capable of forming the self-assembled monolayer to the surface of the protection layer that has been surface-modified by the surface modification unit, thereby forming the self-assembled monolayer; a second treatment liquid supply unit that supplies a second treatment liquid containing second molecules of the same kind or different kind as the first molecules to the surface of the protected layer on which the self-assembled monolayer is formed, thereby chemically adsorbing the second molecules in an area where the self-assembled monolayer is not formed; an etching unit that selectively etches and removes the layer to be etched using the self-assembled monolayer as a protective layer; Equipped with the second treatment liquid supply unit supplies the second treatment liquid at least once until an area ratio (%) of film defects in the self-assembled monolayer formed on the surface of the protective layer becomes equal to or less than an arbitrarily set threshold value. Semiconductor manufacturing equipment.

17. A semiconductor manufacturing apparatus for processing a substrate having a laminate on a surface thereof, comprising: The laminate includes a layer to be protected from etching and a layer to be etched which are alternately laminated, a substrate processing unit for selectively forming a self-assembled monolayer on at least a surface of the layer to be protected; an etching processing unit that selectively etches and removes the layer to be etched using the self-assembled monolayer as a protective layer; Equipped with The substrate processing unit includes: a surface modification unit that performs surface modification on the surface of the protective layer to enable the formation of the self-assembled monolayer; a first treatment liquid supply unit that supplies a first treatment liquid containing first molecules capable of forming the self-assembled monolayer to the surface of the protection layer that has been surface-modified by the surface modification unit, thereby forming the self-assembled monolayer; a second treatment liquid supply unit that supplies a second treatment liquid containing second molecules of the same kind or different kind as the first molecules to the surface of the protected layer on which the self-assembled monolayer is formed, thereby chemically adsorbing the second molecules in an area where the self-assembled monolayer is not formed; Equipped with the second treatment liquid supply unit supplies the second treatment liquid at least once until an area ratio (%) of film defects in the self-assembled monolayer formed on the surface of the protective layer becomes equal to or less than an arbitrarily set threshold value. Semiconductor manufacturing equipment.

18. 18. The semiconductor manufacturing apparatus according to claim 16, wherein the second molecule has a molecular chain length equal to or shorter than that of the first molecule.

19. 18. The semiconductor manufacturing apparatus of claim 16, wherein when the second processing liquid supply unit supplies the second processing liquid to the surface of the protected layer multiple times, the second molecules contained in the second processing liquid supplied earlier have a molecular chain length that is the same as or longer than that of the second molecules contained in the second processing liquid supplied later.

20. the first molecule and the second molecule have a functional group capable of undergoing a dehydration condensation reaction with a hydroxyl group, the surface modification unit performs the surface modification by providing the hydroxyl group to the surface of the substrate, 18. The semiconductor manufacturing apparatus according to claim 16, wherein the first processing liquid supply unit and the second processing liquid supply unit chemically adsorb the first molecule or the second molecule onto the surface of the substrate by a dehydration condensation reaction between the functional group of the first molecule or the second molecule and the hydroxyl group on the surface of the substrate.

21. The surface modification portion is a surface modifying liquid supply unit that provides a hydroxyl group on the surface of the layer to be protected by supplying a surface modifying liquid made of an alkaline solution to the surface of the layer to be protected; 18. The semiconductor manufacturing apparatus according to claim 16, further comprising an ultraviolet irradiating section that irradiates the surface of the substrate with ultraviolet light in an atmosphere containing oxygen atoms, thereby providing hydroxyl groups on the surface of the layer to be protected.

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