Tabernacle Method and Tabernacle Device

Abstract

A film formation method comprises the following (A) to (C): (A) supplying a liquid to the surface of a substrate having adjacent concave and convex portions on its surface. (B) supplying a processing gas that chemically changes the liquid to the surface of the substrate, thereby moving the liquid from the concave portion to the convex portion by means of a reaction between the liquid and the processing gas, and forming a film on the normal surface of the convex portion to expand the step formed on the surface. (C) etching a portion of the film.

Description

Technology Field

[0001] The present disclosure relates to a tabernacle method and a tabernacle apparatus. Background Technology

[0002] Patent Document 1 discloses a method for selectively depositing a film on the upper surface between trenches. Additionally, Patent Document 2 discloses a method for selectively forming a film on a specific area of ​​a substrate without using photolithography technology. This method includes selectively forming Si adsorption sites on the flat surface of the substrate among the flat surface of the substrate and the wall surface of a trench that is concave from the flat surface. Prior art literature

[0003] Specification of U.S. Patent No. 10340135 Japanese Patent Publication No. 2018-117038 The problem to be solved

[0004] One aspect of the present disclosure provides a technique for extending a step difference on a substrate surface including adjacent concave and convex portions. means of solving the problem

[0005] A method for forming a film according to one embodiment of the present disclosure comprises the following (A) to (C): (A) supplying a liquid to the surface of a substrate having adjacent concave and convex portions on its surface. (B) supplying a processing gas that chemically changes the liquid to the surface of the substrate, thereby moving the liquid from the concave portion to the convex portion by means of a reaction between the liquid and the processing gas, and forming a film on the normal surface of the convex portion, thereby expanding the step formed on the surface. (C) etching a portion of the film. Effects of the invention

[0006] According to one embodiment of the present disclosure, the step difference of a substrate surface including adjacent concave and convex portions can be extended. Brief explanation of the drawing

[0007] FIG. 1 is a flowchart illustrating a tabernacle method according to one embodiment. FIG. 2a is a cross-sectional view illustrating an example of step S1. FIG. 2b is a cross-sectional view illustrating an example of step S2. FIG. 2c is a cross-sectional view illustrating an example of the first step of Step S3. FIG. 2d is a cross-sectional view illustrating an example of the second step of Step S3. FIG. 3a is a cross-sectional view illustrating an example immediately preceding step S6. FIG. 3b is a cross-sectional view illustrating an example immediately after step S6. FIG. 4a is a cross-sectional view illustrating an example immediately before step S8. FIG. 4b is a cross-sectional view illustrating an example immediately after step S8. FIG. 5 is a cross-sectional view illustrating a tabernacle apparatus according to one embodiment. Figure 6a is an SEM image of the substrate for Example 1, after step S2 and before step S3. Figure 6b is an SEM image of the substrate for Example 1, and an SEM image during step S3. Figure 6c is an SEM image of the substrate for Example 1 and an SEM image after step S3. Figure 7a is an SEM image of the substrate for Example 2, after step S2 and before S3. Figure 7b is an SEM image of the substrate for Example 2 and an SEM image after step S3. Figure 8 is a diagram illustrating the relationship between the processing time of Step S9 (Table 2) regarding Example 3 and the thickness of the liquid in the depression. Figure 9a is an SEM image of the substrate after processing for Example 4. Figure 9b is an SEM image of the substrate after processing for Example 5. Figure 9c is an SEM image of the substrate after processing for Example 6. Figure 9d is an SEM image of the substrate after processing for Example 7. Figure 10a is an SEM image of the substrate after processing for Example 8. Figure 10b is an SEM image of the substrate after processing for Example 9. Fig. 10c is an SEM image of the substrate after processing for Example 10. Figure 11a is an SEM image of the substrate after processing for Example 11. Figure 11b is an SEM image of the substrate after processing for Example 12. Figure 12a is an SEM image of the substrate after processing for Example 13. Figure 12b is an SEM image of the substrate after processing for Example 14. Figure 13 is an SEM image of the substrate after processing for Example 17. Figure 14 is an SEM image of the substrate after processing for Example 18. Figure 15a is an SEM image of a substrate obtained in Example 19, and is an SEM image of a substrate with an initial depth (A0) of 8 nm. Figure 15b is an SEM image of a substrate obtained in Example 19, and is an SEM image of a substrate with an initial depth (A0) of 12 nm. Fig. 15c is an SEM image of a substrate obtained in Example 19, and is an SEM image of a substrate with an initial depth (A0) of 18 nm. FIG. 15d is an SEM image of a substrate obtained in Example 19, and is an SEM image of a substrate with an initial depth (A0) of 150 nm. Figure 16a is an SEM image of a substrate obtained in Example 20, and is an SEM image of a substrate with an initial depth (A0) of 8 nm. Figure 16b is an SEM image of a substrate obtained in Example 20, and is an SEM image of a substrate with an initial depth (A0) of 12 nm. Fig. 16c is an SEM image of a substrate obtained in Example 20, and is an SEM image of a substrate with an initial depth (A0) of 18 nm. Figure 17a is an SEM image of a substrate obtained in Example 21, and is an SEM image of a substrate with an initial depth (A0) of 8 nm. Figure 17b is an SEM image of a substrate obtained in Example 21, and is an SEM image of a substrate with an initial depth (A0) of 12 nm. Fig. 17c is an SEM image of a substrate obtained in Example 21, and is an SEM image of a substrate with an initial depth (A0) of 18 nm. Figure 18a is an SEM image of a substrate obtained in Example 22, and is an SEM image of a substrate with an initial depth (A0) of 8 nm. Figure 18b is an SEM image of a substrate obtained in Example 22, and is an SEM image of a substrate with an initial depth (A0) of 12 nm. Fig. 18c is an SEM image of a substrate obtained in Example 22, and is an SEM image of a substrate with an initial depth (A0) of 18 nm. Fig. 18d is an SEM image of a substrate obtained in Example 22, and is an SEM image of a substrate with an initial depth (A0) of 150 nm. Figure 19a is an SEM image of the substrate for Example 23, and is an SEM image showing the state between step S2 and step S3. Figure 19b is an SEM image of the substrate for Example 23, and is an SEM image showing the state at the completion of Step S3. Specific details for implementing the invention

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In addition, in each drawing, identical or corresponding components are given the same reference numerals, and descriptions may be omitted.

[0009] Referring to FIG. 1 and others, an example of a tabernacle method is described. As illustrated in FIG. 1, the tabernacle method has, for example, steps S1 to S8. Additionally, the tabernacle method may have at least steps S1 to S3 and S6. Furthermore, the tabernacle method may have additional steps other than steps S1 to S8.

[0010] In step S1 of FIG. 1, a substrate (W) is prepared that includes adjacent concave portions (Wb) and convex portions (Wc) on its surface (Wa), as illustrated in FIG. 2a. Preparing the substrate (W) includes, for example, bringing the substrate (W) into the interior of a processing vessel (2) described later. The substrate (W) includes, for example, a silicon wafer (W1). The substrate (W) may include a compound semiconductor wafer or a glass substrate instead of a silicon wafer (W1).

[0011] The concave portion (Wb) and the convex portion (Wc) are formed, for example, on the surface of a silicon wafer (W1). The substrate (W) may include an unillustrated film formed on the surface of the silicon wafer (W1), and the concave portion (Wb) and the convex portion (Wc) may be formed on the film. The film may include one or more selected from insulating films, conductive films, and semiconductor films. The concave portion (Wb) is a trench or a hole, etc. The hole includes a via hole. The convex portion (Wc) may be a filler or a pin, etc.

[0012] The substrate surface (Wa) includes, for example, a concave bottom surface (Wb1), a concave side surface (Wb2), and a convex top surface (Wc1). For example, the convex top surface (Wc1) is a flat surface, and the concave portion (Wb) becomes concave from the convex top surface (Wc1). The depth of the concave portion (Wb) indicates the size of the step difference.

[0013] The initial depth (A0) of the concave portion (Wb) is, for example, 3 nm to 10,000 nm. The initial width (B0) of the concave portion (Wb) is, for example, 1 nm to 1,000 nm. The ratio (A0 / B0) of the initial depth (A0) to the initial width (B0) is, for example, 0.05 to 200.

[0014] In step S2 of FIG. 1, a liquid (L) is supplied to the substrate surface (Wa) as shown in FIG. 2b. The liquid (L) may cover not only the concave portion (Wb) but also the convex normal surface (Wc1). In this case, the liquid surface of the liquid (L) may be a horizontal plane. Additionally, the liquid (L) may be filled only into the concave portion (Wb) and may not cover the convex normal surface (Wc1).

[0015] It is desirable for the liquid (L) to have strong intermolecular forces. The stronger the intermolecular forces, the stronger the cohesive force. If the cohesive force of the liquid (L) is high, the evaporation of the liquid (L) can be prevented. The intermolecular force of the liquid (L) is, for example, 30 kJ / mol or higher.

[0016] The liquid (L) is, for example, a halide. The liquid halide is formed, for example, by the reaction of a source gas of the halide and a reaction gas that reacts with the source gas. The formation of the liquid (L) may be facilitated by plasmaizing both the source gas and the reaction gas, or by plasmaizing the reaction gas. The source gas is, for example, TiCl4 gas, and the reaction gas is, for example, H2 gas.

[0017] TiCl4 gas and H2 gas are generally used for the formation of a Ti film, rather than for the formation of a liquid (L). The Ti film is formed, for example, by the CVD (Chemical Vapor Deposition) method or the ALD (Atmotic Layer Deposition) method. In the CVD method, TiCl4 gas and H2 gas are supplied simultaneously to the substrate (W). Meanwhile, in the ALD method, TiCl4 gas and H2 gas are supplied alternately to the substrate (W). According to the CVD or ALD method, it is presumed that the following equations (1) to (3) contribute to the formation of the Ti film.

[0018] TiCl4 + H2 → TiH x Cl y … (1)

[0019] TiH x Cl y →TiCl2+HCl … (2)

[0020] TiCl2+H2→Ti+HCl … (3)

[0021] In addition, in the above equations (2) and (3), TiCl2 may be TiCl or TiCl3.

[0022] In the formation of the Ti film, the temperature of the substrate (W) is controlled to be 400°C or higher. As a result, the reactions of the above formulas (1) to (3) proceed sequentially, and the Ti film is formed.

[0023] Meanwhile, in the formation of the liquid (L), the temperature of the substrate (W) is controlled to -100°C to 390°C, preferably 20°C to 350°C. As a result, the reaction of formula (2) and the reaction of (3) are suppressed, so TiH x Cl y A liquid (L) containing [the component] is formed. The liquid (L) may contain Ti, TiCl, TiCl2, TiCl3, or TiCl4. The temperature of the substrate (W) should be lower than the decomposition point of the liquid (L).

[0024] In addition, the source gas is not limited to TiCl4 gas. For example, the source gas may be a silicon halogenated gas such as SiCl4 gas, Si2Cl6 gas, SiHCl3 gas, or a metal halogenated gas such as WCl4 gas, VCl4 gas, AlCl3 gas, MoCl5 gas, SnCl4 gas, GeCl4 gas. The source gas may contain a halogen, and as the halogen, it may contain bromine (Br), iodine (I), or fluorine (F), etc., instead of chlorine (Cl). When the temperature of the substrate (W) is low, the reaction similar to that of Equation (1) above mainly proceeds with these source gases, so a liquid (L) of the halogenate is formed.

[0025] In addition, the reaction gas is not limited to H2 gas. The reaction gas may be any gas capable of forming a liquid (L) upon reaction with the source gas. For example, the reaction gas may be D2 gas. The reaction gas may be supplied together with an inert gas such as argon gas.

[0026] Step S2 includes, for example, simultaneously supplying a source gas and a reaction gas to a substrate (W). In this case, Step S2 may also include plasmaizing both the source gas and the reaction gas. Plasmaization can promote the reaction between the source gas and the reaction gas. Additionally, plasmaization makes it easier to form a liquid (L) at a low substrate temperature.

[0027] Additionally, in this embodiment, Step S2 includes supplying the source gas and the reaction gas simultaneously to the substrate (W), but may also include supplying the source gas and the reaction gas alternately to the substrate (W). In the latter case, Step S2 may also include plasmaizing the reaction gas. Plasmaization can promote the reaction between the source gas and the reaction gas. Additionally, plasmaization makes it easier to form the liquid (L) at a low substrate temperature. Additionally, Step S2 may include supplying only the source gas to the substrate (W).

[0028] The liquid (L) may be one having strong intermolecular forces and may be an ionic liquid, a metal in a liquid state, or a polymer in a liquid state. The metal may be a pure metal or an alloy. The polymer may be, for example, Si2Cl6 gas, SiCl4 gas, SiHCl3 gas, SiH2Cl2 gas, SiH3Cl gas, SiH4 gas, Si2H6 gas, Si3H8 gas, Si4H 10 The oligomer or polymer formed by polymerizing two or more molecules of gas, cyclohexasilane gas, tetraethoxysilane (TEOS) gas, dimethyldiethoxysilane (DMDEOS) gas, 2,4,6,8-tetramethylcyclotetrasiloxane (TMCTS) gas, or trisilylamine (TSA) gas may be, for example, polysiloxane, polysilane, or polysilazane. Additionally, the liquid (L) may be silanol, etc. These liquids (L) are supplied to the concave portion (Wb) of the substrate (W) by a spin coating method, or synthesized inside a processing vessel that accommodates the substrate (W) and supplied to the concave portion (Wb) of the substrate (W).

[0029] In step S3 of FIG. 1, as shown in FIG. 2c, a processing gas (G) that chemically changes the liquid (L) is supplied to the substrate surface (Wa), and the liquid (L) is moved from the concave portion (Wb) to the convex normal surface (Wc1) by the reaction between the processing gas (G) and the liquid (L), and the step of the substrate surface (Wa) is expanded by forming a film (W2) on the convex normal surface (Wc1) as shown in FIG. 2d. The size of the step is represented by the depth (A) of the concave portion (Wb). By forming the film (W2), the depth (A) of the concave portion (Wb) becomes larger than the initial depth (A0).

[0030] The film (W2) may also be formed on the bottom surface of the concave portion (Wb1). If the thickness of the film (W2) on the bottom surface of the concave portion (Wb1) is thinner than the thickness of the film (W2) on the top surface of the convex portion (Wc1), the step difference of the substrate surface (Wa) can be expanded.

[0031] The film (W2) may also be formed on the concave side (Wb2). If the thickness of the film (W2) on the concave side (Wb2) is thinner than the thickness of the film (W2) on the convex normal surface (Wc1), for example, even if the film (W2) is isotropically etched, the step difference of the substrate surface (Wa) can be expanded by the formation of the film (W2).

[0032] In addition, the thickness of the film (W2) on the concave side (Wb2) may be zero. Adjacent concave sides (Wb2) must not be connected to each other, and the concave (Wb) must not be blocked. This is because if the concave (Wb) is blocked, the step difference will disappear.

[0033] The film (W2) may be a solid or a viscous material. The thickness of the film (W2) can be controlled by the supply amount of liquid (L).

[0034] The processing gas (G) is supplied, for example, from above the substrate surface (Wa) and reacts with the liquid (L). The liquid (L) reacts with the processing gas (G) and undergoes a chemical change. Since the chemical change proceeds slowly from the surface of the liquid (L), a difference in surface tension occurs, and volume expansion or contraction occurs from the surface of the liquid (L), causing the liquid (L) to become unstable and convection to occur. As the surface of the liquid (L) changes into a material with high surface tension due to the reaction with the processing gas (G), the liquid (L) moves toward the convex normal surface (Wc1). Additionally, the liquid (L) moves toward the convex normal surface (Wc1) driven by the increase or decrease in volume caused by the chemical change on the surface of the liquid (L). Although not illustrated, all of the liquid (L) may eventually move to the convex normal surface (Wc1) through the reaction with the processing gas (G).

[0035] In addition, during the chemical change of the liquid (L), degassing occurs from the liquid (L) due to the reaction between the liquid (L) and the processing gas (G). The movement of the liquid (L) caused by the generation of degassing is also considered to be a factor contributing to the movement of the liquid (L). Furthermore, minute vibrations of the substrate (W) are also considered to be a factor contributing to the movement of the liquid (L).

[0036] The treatment gas (G) contains elements that are introduced into the liquid (L) by, for example, through a reaction with the liquid (L). That is, the treatment gas (G) contains elements that are introduced into the membrane (W2). For example, oxygen of the treatment gas (G) is introduced into the liquid (L) to obtain a membrane (W2) that is an oxide. Or, nitrogen of the treatment gas (G) is introduced into the liquid (L) to obtain a membrane (W2) that is a nitride. It is sufficient that elements in the treatment gas (G) are introduced into the liquid (L), and in the process, elements constituting the liquid (L) may be degassed.

[0037] For example, the treatment gas (G) includes an oxygen-containing gas. The oxygen-containing gas includes oxygen as an element introduced into the liquid (L). The oxygen-containing gas may also include nitrogen as an element introduced into the liquid (L). The oxygen-containing gas includes, for example, O2 gas, O3 gas, H2O gas, NO gas, or N2O gas.

[0038] The treatment gas (G) may include a nitrogen-containing gas. The nitrogen-containing gas includes nitrogen as an element introduced into the liquid (L). The nitrogen-containing gas includes, for example, N2 gas, NH3 gas, N2H4 gas, or N2H2 gas.

[0039] The treatment gas (G) may include a hydride gas. The hydride gas includes an element bonded to hydrogen, such as Si, Ge, B, C, or P, as an element introduced into the liquid (L). The hydride gas includes, for example, a hydrocarbon gas such as SiH4 gas, Si2H6 gas, GeH4 gas, B2H6 gas, C2H4 gas, or PH3 gas.

[0040] The treatment gas (G) may degas the elements constituting the liquid (L) by reacting with the liquid (L). For example, the treatment gas (G) includes a reducing gas. The reducing gas is, for example, hydrogen (H2) gas or deuterium (D2) gas.

[0041] The treatment gas (G) may be supplied together with an inert gas such as argon gas.

[0042] Step S3 may include plasmaizing the treatment gas (G). Plasmaization can promote the reaction between the treatment gas (G) and the liquid (L).

[0043] In step S4 of FIG. 1, the film (W2) formed in step S3 is modified. The film (W2) after modification has superior chemical resistance compared to the film (W2) before modification. For example, the film (W2) after modification has a lower etching rate with respect to dilute hydrofluoric acid (DHF) compared to the film (W2) before modification.

[0044] The modification of the membrane (W2) comprises, for example, at least one of the following (A) to (B). (A) Reduce the halogen element or hydrogen element in the membrane (W2). (B) Densify the membrane (W2). Densification of the membrane (W2) can be achieved, for example, by terminating the unbonded loss of the membrane (W2) with an element contained in the modification gas, or by promoting the bonding of existing elements in the membrane (W2).

[0045] In step S4, a reforming gas may be supplied to the membrane (W2). If the reforming gas of S4 and the treatment gas (G) of S3 are the same gas, they are supplied under different conditions. Specifically, for example, while the reforming gas is plasmafied, the treatment gas (G) is not plasmafied. Alternatively, the reforming gas is supplied at a higher temperature or higher pressure compared to the treatment gas (G).

[0046] However, the reforming gas of S4 and the treatment gas (G) of S3 may be different gases. For example, the treatment gas (G) is nitrogen gas and is plasmafied, whereas the reforming gas is ammonia (NH3) gas and is plasmafied, or hydrazine (N2H4) gas. Alternatively, the treatment gas (G) is oxygen (O2) gas, while the reforming gas is ozone (O3) gas or water vapor (H2O).

[0047] In step S5 of FIG. 1, it is checked whether the first cycle has been performed M times (M is an integer greater than or equal to 1). One first cycle includes steps S2 to S4. Additionally, the first cycle may include at least steps S2 to S3 and may not include step S4. M may be an integer greater than or equal to 2.

[0048] If the number of times the first cycle is performed is less than M (step S5, "No"), the first cycle is performed again because the magnitude of the step difference on the substrate surface (Wa) is less than the target value. M is not particularly limited, but is, for example, 2 to 100, and preferably 5 to 20.

[0049] During the first cycle, which is performed M times, adjacent concave sides (Wb2) must not be connected to each other, and the concave (Wb) must not be blocked. This is because if the concave (Wb) becomes blocked, the step difference disappears. An upper limit value of M is set so that the concave (Wb) does not become blocked.

[0050] Meanwhile, when the number of times the first cycle is performed reaches M (Step S5, "Yes"), the magnitude of the step difference on the substrate surface (Wa) has reached the target value, so the processing after Step S6 is performed. An example of the substrate (W) immediately before Step S6 is shown in FIG. 3a.

[0051] As illustrated in FIG. 3a, when the first cycle is repeated, adjacent sides of the concave portion (Wb2) become closer to each other, and the width (B) of the concave portion (Wb) becomes narrower. Additionally, when the first cycle is repeated, a protrusion may be formed on the bottom surface (Wb1) of the concave portion.

[0052] In step S6 of FIG. 1, a portion of the film (W2) is etched. By etching, the width (B) of the concave portion (Wb) can be expanded as shown in FIG. 3b. Although not shown, the width (B) of the concave portion (Wb) can also be returned to the initial width (B0). When the width of the concave portion (Wb) is expanded by etching, it becomes possible to perform the first cycle again, thereby enabling further expansion of the step. Additionally, by etching, it is also possible to remove the protrusions on the bottom surface (Wb1) of the concave portion as shown in FIG. 3b.

[0053] The etching may be either isotropic etching or anisotropic etching. A combination of isotropic etching and anisotropic etching may also be used. Isotropic etching can etch not only the bottom surface of the concave part (Wb1) and the top surface of the convex part (Wc1), but also the side surface of the concave part (Wb2), making it effective for expanding the width (B) of the concave part (Wb). Meanwhile, anisotropic etching can selectively etch the bottom surface of the concave part (Wb1) and the top surface of the convex part (Wc1) with respect to the side surface of the concave part (Wb2).

[0054] Etching can be either dry etching or wet etching, but preferably dry etching. In dry etching, an etching gas is supplied to the substrate surface (Wa). In dry etching, H2 gas, O2 gas, or NH3 gas, etc., may be supplied to the substrate surface (Wa) along with the etching gas.

[0055] When dry etching is thermal etching, for example, Cl2 gas, ClF3 gas, F2 gas, or HF gas is used as the etching gas. On the other hand, when dry etching is plasma etching, for example, Cl2 gas, CF4 gas, CHF3 gas, C4F8 gas, or SF6 gas is used as the etching gas to be plasmafied.

[0056] Etching may be performed by alternately supplying etching gas and reaction gas, as in ALE (Atomic Layer Etching). Examples of etching gases used include Cl2 gas, CF4 gas, C4F8 gas, WF6 gas, etc. As reaction gases, Ar gas, He gas, H2 gas, BCl3 gas, etc. are used. The reaction gas may be supplied in a plasma form.

[0057] In step S7 of FIG. 1, it is checked whether the second cycle has been performed N times (N is an integer greater than or equal to 1). One second cycle includes M first cycles and step S6 performed after M first cycles. N may be an integer greater than or equal to 2.

[0058] If the number of times the second cycle is performed is less than N (step S7, "No"), the second cycle is performed again because the magnitude of the step difference on the substrate surface (Wa) is less than the target value. N is not particularly limited, but is, for example, 1 to 10, and preferably 1 to 5.

[0059] Meanwhile, when the number of times the second cycle is performed reaches N (Step S7, "Yes"), the magnitude of the step difference on the substrate surface (Wa) has reached the target value, so the processing after Step S8 is performed. An example of the substrate (W) immediately before Step S8 is shown in FIG. 4a.

[0060] As illustrated in FIG. 4a, when the second cycle is repeated, adjacent sides of the concave portion (Wb2) become closer to each other, and the width (B) of the concave portion (Wb) becomes narrower. Additionally, when the second cycle is repeated, a protrusion may be formed on the bottom surface (Wb1) of the concave portion.

[0061] In step S8 of FIG. 1, a portion of the film (W2) is etched, just as in step S6. By etching, the width (B) of the concave portion (Wb) can be expanded, as shown in FIG. 4b. Although not shown, the width (B) of the concave portion (Wb) can be returned to the initial width (B0).

[0062] It is also possible to remove the protrusions on the bottom surface of the concave portion (Wb1) by etching, as shown in FIG. 4b. Additionally, by etching, a material different from the film (W2) (e.g., silicon wafer (W1)) can be exposed on the bottom surface of the concave portion (Wb1). Although not shown, by etching, a material different from the film (W2) (e.g., silicon wafer (W1)) can also be exposed on the side surface of the concave portion (Wb2).

[0063] After etching, for example, the bottom surface of the concave portion (Wb1) is formed by a silicon wafer, the side surface of the concave portion (Wb2) is formed by a film (W2), and the top surface of the convex portion (Wc1) is formed by a film (W2). Additionally, when the width (B) of the concave portion (Wb) is returned to the initial width (B0), the side surface of the concave portion (Wb2) is formed by the film (W2) and the silicon wafer.

[0064] The etching may be either isotropic etching or anisotropic etching. A combination of isotropic etching and anisotropic etching may also be used. Isotropic etching can etch not only the bottom surface of the concave part (Wb1) and the top surface of the convex part (Wc1), but also the side surface of the concave part (Wb2), making it effective for expanding the width (B) of the concave part (Wb). Meanwhile, anisotropic etching can selectively etch the bottom surface of the concave part (Wb1) and the top surface of the convex part (Wc1) with respect to the side surface of the concave part (Wb2).

[0065] Next, with reference to FIG. 5, a membrane device (1) will be described. The membrane device (1) comprises a roughly cylindrical, airtight processing vessel (2). An exhaust chamber (21) is provided in the center of the bottom wall of the processing vessel (2). The exhaust chamber (21) has, for example, a roughly cylindrical shape that protrudes downward. An exhaust pipe (22) is connected to the exhaust chamber (21), for example, from the side of the exhaust chamber (21).

[0066] An exhaust section (24) is connected to the exhaust pipe (22) through a pressure regulating section (23). The pressure regulating section (23) is equipped with a pressure regulating valve, such as a butterfly valve. The exhaust pipe (22) is configured to reduce the pressure inside the processing vessel (2) by means of the exhaust section (24). A return port (25) is provided on the side of the processing vessel (2). The return port (25) is opened and closed by a gate valve (26). The transfer of a substrate (W) between the processing vessel (2) and the return chamber (not shown) is carried out through the return port (25).

[0067] A stage (3) is provided within the processing container (2). The stage (3) is a holding support that holds and supports the substrate (W) horizontally with the surface (Wa) of the substrate (W) facing upward. The stage (3) is formed in a roughly circular shape when viewed in a planar view and is supported by a support member (31). On the surface of the stage (3), a roughly circular concave portion (32) is formed for loading, for example, a substrate (W) with a diameter of 300 mm. The concave portion (32) has an inner diameter slightly larger than the diameter of the substrate (W). The depth of the concave portion (32) is configured to be, for example, approximately equal to the thickness of the substrate (W). The stage (3) is formed by a ceramic material such as aluminum nitride (AlN). Additionally, the stage (3) may be formed by a metal material such as nickel (Ni). In addition, instead of the concave portion (32), a guide ring that guides the substrate (W) may be provided on the periphery of the surface of the stage (3).

[0068] For example, a grounded lower electrode (33) is embedded in the stage (3). A heating mechanism (34) is embedded below the lower electrode (33). The heating mechanism (34) heats the substrate (W) loaded on the stage (3) to a set temperature by being supplied from a power supply unit (not shown) based on a control signal from the control unit (100). If the entire stage (3) is made of metal, the entire stage (3) functions as a lower electrode, so the lower electrode (33) does not need to be embedded in the stage (3). The stage (3) is provided with a plurality (e.g., three) of lifting pins (41) for holding and supporting the substrate (W) loaded on the stage (3) and for lifting and lowering it. The material of the lifting pins (41) may be ceramics such as alumina (Al2O3) or quartz. The lower end of the lifting pins (41) is installed on a support plate (42). The support plate (42) is connected to a lifting mechanism (44) provided on the outside of the processing container (2) via a lifting shaft (43).

[0069] The lifting mechanism (44) is installed, for example, at the bottom of the exhaust chamber (21). A bellows (45) is provided between the opening (211) for the lifting shaft (43) formed on the lower surface of the exhaust chamber (21) and the lifting mechanism (44). The shape of the support plate (42) may be such that it can be lifted without interfering with the support member (31) of the stage (3). The lifting pin (41) is configured to be able to be lifted between the upper surface of the stage (3) and the lower surface of the stage (3) by the lifting mechanism (44).

[0070] A gas supply unit (5) is provided in the ceiling wall (27) of the processing vessel (2) via an insulating member (28). The gas supply unit (5) forms an upper electrode and faces the lower electrode (33). A high-frequency power source (512) is connected to the gas supply unit (5) through a matching device (511). By supplying high-frequency power of 450 kHz to 2.45 GHz, preferably 450 kHz to 100 MHz, from the high-frequency power source (512) to the upper electrode (gas supply unit (5)), a high-frequency electric field is generated between the upper electrode (gas supply unit (5)) and the lower electrode (33), thereby generating a capacitively coupled plasma. The plasma generation unit (51) includes a matching device (511) and a high-frequency power source (512). Additionally, the plasma generating unit (51) is not limited to capacitively coupled plasma and may generate other plasmas such as inductively coupled plasma.

[0071] The gas supply unit (5) is provided with a hollow gas supply chamber (52). On the lower surface of the gas supply chamber (52), a plurality of holes (53) are evenly arranged, for example, to distribute and supply the processing gas into the processing container (2). A heating mechanism (54) is installed above the gas supply chamber (52), for example, in the gas supply unit (5). The heating mechanism (54) is heated to a set temperature by being supplied with power from a power supply unit (not shown) based on a control signal from the control unit (100).

[0072] A gas supply channel (6) is provided in the gas supply room (52). The gas supply channel (6) is connected to the gas supply room (52). Upstream of the gas supply channel (6), gas sources (G61, G62, G63, G64, G65) are connected through gas lines (L61, L62, L63, L64, L65), respectively.

[0073] The gas source (G61) is a gas source of TiCl4 and is connected to the gas supply line (6) through the gas line (L61). In the gas line (L61), a mass flow controller (M61), a storage tank (T61), and a valve (V61) are provided in this order from the gas source (G61) side. The mass flow controller (M61) controls the flow rate of the TiCl4 gas flowing through the gas line (L61). The storage tank (T61) can increase the pressure of the TiCl4 gas within the storage tank (T61) by storing the TiCl4 gas supplied from the gas source (G61) through the gas line (L61) when the valve (V61) is closed. The valve (V61) performs the supply and blocking of the TiCl4 gas to the gas supply line (6) through opening and closing operations.

[0074] The gas source (G62) is an Ar gas source and is connected to the gas supply line (6) through the gas line (L62). In the gas line (L62), a mass flow controller (M62) and a valve (V62) are provided in this order from the gas source (G62) side. The mass flow controller (M62) controls the flow rate of Ar gas flowing through the gas line (L62). The valve (V62) supplies and cuts off Ar gas to the gas supply line (6) by opening and closing operations.

[0075] The gas source (G63) is an O2 gas source and is connected to the gas supply path (6) through the gas line (L63). In the gas line (L63), a mass flow controller (M63) and a valve (V63) are provided in this order from the gas source (G63) side. The mass flow controller (M63) controls the flow rate of O2 gas flowing through the gas line (L63). The valve (V63) supplies and cuts off O2 gas to the gas supply path (6) through opening and closing operations.

[0076] The gas source (G64) is an H2 gas source and is connected to the gas supply line (6) through the gas line (L64). In the gas line (L64), a mass flow controller (M64) and a valve (V64) are provided in this order from the gas source (G64) side. The mass flow controller (M64) controls the flow rate of H2 gas flowing through the gas line (L64). The valve (V64) controls the supply and cutoff of H2 gas to the gas supply line (6) through opening and closing operations.

[0077] The gas source (G65) is a gas source of ClF3 and is connected to the gas supply line (6) through the gas line (L65). In the gas line (L65), a mass flow controller (M65) and a valve (V65) are provided in this order from the gas source (G65) side. The mass flow controller (M65) controls the flow rate of the ClF3 gas flowing through the gas line (L65). The valve (V65) controls the supply and cutoff of ClF3 gas to the gas supply line (6) through opening and closing operations.

[0078] The film deposition device (1) is equipped with a control unit (100) and a memory unit (101). The control unit (100) is equipped with a CPU, RAM, ROM, etc. (not all shown), and controls the film deposition device (1) comprehensively by executing, for example, a computer program stored in the ROM or memory unit (101) on the CPU. Specifically, the control unit (100) executes a control program stored in the memory unit (101) on the CPU to control the operation of each component of the film deposition device (1), thereby performing film deposition processing on the substrate (W).

[0079] Next, referring again to FIG. 5, the operation of the film formation device (1) will be described. First, the control unit (100) opens the gate valve (26) to transport the substrate (W) into the processing container (2) by means of a transport mechanism and loads it onto the stage (3). The substrate (W) is loaded horizontally with its surface (Wa) facing upward. The control unit (100) withdraws the transport mechanism from the processing container (2) and closes the gate valve (26). Subsequently, the control unit (100) heats the substrate (W) to a predetermined temperature by means of a heating mechanism (34) of the stage (3) and adjusts the pressure inside the processing container (2) to a predetermined pressure by means of a pressure adjustment unit (23). For example, bringing the substrate (W) into the processing container (2) is included in step S1 of FIG. 1.

[0080] Next, in step S2 of FIG. 1, the control unit (100) opens valves (V61, V62, V64) to simultaneously supply TiCl4 gas, Ar gas, and H2 gas into the treatment vessel (2). Valves (V63, V65) are closed. Due to the reaction between TiCl4 gas and H2 gas, TiH x Cl y Liquid (L) is supplied to the concave portion (Wb) of the substrate (W).

[0081] The specific processing conditions of Step S2 are, for example, as follows.

[0082] TiCl4 gas flow rate: 1 sccm to 100 sccm

[0083] Ar gas flow rate: 10 sccm to 100,000 sccm, preferably 100 sccm to 20,000 sccm

[0084] H2 gas flow rate: 1 sccm to 50,000 sccm, preferably 10 sccm to 10,000 sccm

[0085] Processing time: 1 second to 1800 seconds

[0086] Treatment temperature: -100℃ to 390℃, preferably 20℃ to 350℃

[0087] Processing pressure: 0.1 Pa to 10,000 Pa, preferably 0.1 Pa to 2,000 Pa

[0088] In step S2, the control unit (100) may generate plasma by the plasma generation unit (51) to promote the reaction between TiCl4 gas and H2 gas. When the control unit (100) supplies TiCl4 gas and H2 gas simultaneously, it plasmaizes both TiCl4 gas and H2 gas.

[0089] Additionally, in step S2, the control unit (100) may supply TiCl4 gas and H2 gas alternately instead of supplying them simultaneously into the treatment vessel (2). In this case, the control unit (100) may plasmaize only the H2 gas among the TiCl4 gas and H2 gas.

[0090] After step S2, valves (V61, V64) are closed. At this time, since valve (V62) is open, Ar is supplied into the treatment vessel (2), and the gas remaining inside the treatment vessel (2) is discharged through the exhaust pipe (22), thereby replacing the atmosphere inside the treatment vessel (2) with Ar.

[0091] Next, in step S3 of FIG. 1, the control unit (100) opens the valve (V63) to supply O2 gas together with Ar gas into the processing vessel (2). Due to the reaction between the O2 gas and the liquid (L), the liquid (L) moves from the concave portion (Wb) to the convex normal surface (Wc1), and a film (W2) is formed on the convex normal surface (Wc1). As a result, the step height of the substrate surface (Wa) is expanded.

[0092] The specific processing conditions for Step S3 are, for example, as follows.

[0093] O2 gas flow rate: 1 sccm to 100,000 sccm, preferably 1 sccm to 10,000 sccm

[0094] Ar gas flow rate: 10 sccm to 100,000 sccm, preferably 100 sccm to 20,000 sccm

[0095] Processing time: 1 second to 1800 seconds

[0096] Treatment temperature: -100℃ to 390℃, preferably 20℃ to 350℃

[0097] Processing pressure: 0.1 Pa to 10,000 Pa, preferably 0.1 Pa to 2,000 Pa

[0098] Next, in step S4 of FIG. 1, just as in step S3, the control unit (100) supplies O2 gas together with Ar gas into the treatment vessel (2). Also, in step S4, unlike step S3, the control unit (100) generates plasma by the plasma generation unit (51) and modifies the membrane (W2). The specific treatment conditions of step S4 are the same as those of step S3, except for generating plasma, so the description is omitted.

[0099] After step S4, the valve (V63) is closed. At this time, since the valve (V62) is open, Ar is supplied into the treatment vessel (2), and the gas remaining inside the treatment vessel (2) is discharged through the exhaust pipe (22), thereby replacing the atmosphere inside the treatment vessel (2) with Ar.

[0100] Next, in step S5 of FIG. 1, the control unit (100) checks whether the first cycle has been performed M times (M is a natural number greater than or equal to 1). One first cycle includes steps S2 to S4. Additionally, the first cycle may include at least steps S2 to S3 and may not include step S4.

[0101] If the number of times the first cycle is executed is less than M (step S5, "No"), the control unit (100) executes the first cycle again. Meanwhile, if the number of times the first cycle is executed reaches M (step S5, "Yes"), the control unit (100) executes step S6.

[0102] Next, in step S6 of FIG. 1, the control unit (100) opens the valve (V65) to supply ClF3 gas together with Ar gas into the processing vessel (2). A portion of the membrane (W2) is etched by the ClF3 gas. Also, in step S6, the control unit (100) may generate plasma by the plasma generation unit (51) or may plasmaize the ClF3 gas.

[0103] The specific processing conditions for Step S6 are, for example, as follows.

[0104] ClF3 gas flow rate: 1 sccm to 100 sccm

[0105] Ar gas flow rate: 10 sccm to 100,000 sccm, preferably 100 sccm to 20,000 sccm

[0106] Processing time: 1 second to 1800 seconds

[0107] Processing temperature: 30℃ to 350℃, preferably 80℃ to 200℃

[0108] Processing pressure: 0.1 Pa to 10,000 Pa, preferably 0.1 Pa to 2,000 Pa

[0109] After step S6, the valve (V65) is closed. At this time, since the valve (V62) is open, Ar is supplied into the treatment vessel (2), and the gas remaining inside the treatment vessel (2) is discharged through the exhaust pipe (22), thereby replacing the atmosphere inside the treatment vessel (2) with Ar.

[0110] Additionally, Step S6 and Steps S2 to S4 are performed inside the same processing container (2) in this embodiment, but may be performed inside a different processing container (2).

[0111] Next, in step S7 of FIG. 1, the control unit (100) checks whether the second cycle has been performed N times (N is a natural number greater than or equal to 1). One second cycle includes M times the first cycle and step S6 performed after M times the first cycle.

[0112] If the number of times the second cycle is executed is less than N (step S7, "No"), the control unit (100) executes the second cycle again. Meanwhile, if the number of times the second cycle is executed reaches N (step S7, "Yes"), the control unit (100) executes step S8.

[0113] Next, in step S8 of FIG. 1, the control unit (100) opens the valve (V65) to supply ClF3 gas together with Ar gas into the processing vessel (2). A portion of the membrane (W2) is etched by the ClF3 gas. Also, in step S8, the control unit (100) may generate plasma by the plasma generation unit (51) or may plasmaize the ClF3 gas.

[0114] The specific processing conditions of Step S8 are the same as those of Step S6, so the explanation is omitted. After Step S8, the valve (V65) is closed. At this time, since the valve (V62) is open, Ar is supplied into the processing vessel (2), and the gas remaining inside the processing vessel (2) is discharged through the exhaust pipe (22), thereby replacing the atmosphere inside the processing vessel (2) with an Ar atmosphere.

[0115] Additionally, Step S8 and Steps S2 to S4 are performed inside the same processing container (2) in this embodiment, but may be performed inside a different processing container (2).

[0116] After step S8, the control unit (100) removes the substrate (W) from the processing container (2) in the reverse order of bringing the substrate (W) into the processing container (2).

[0117] [Example]

[0118] Next, examples and the like will be described. Among the following Examples 1 to 23, Examples 1 to 19 and Example 23 are reference examples, and Examples 20 to 22 are examples. In the following Examples 1 to 18 and Example 23, before introducing the substrate (W) into the processing vessel (2) shown in FIG. 5, a concave portion and a convex portion were formed in advance on the surface (Wa) of the substrate. The pre-formed convex portion normal surface (Wc1) is hereinafter also referred to as the convex portion normal surface (Wd).

[0119] <Examples 1 to 2>

[0120] In Examples 1 and 2, steps S1 to S3 and S5 were performed using the film formation device (1) shown in FIG. 5 under the processing conditions shown in Table 1, and steps S4 and S6 to S8 were not performed.

[0121]

[0122] In Table 1, the "convex normal surface" is the material of the convex normal surface (Wd) formed in advance before Step S2. The material of the concave side surface formed in advance before Step S2 is the same as the material of the convex normal surface (Wd). The "concave bottom surface" is the material of the concave bottom surface formed in advance before Step S2. In addition, "○" in various gases means that various gases have been supplied, and "ON" in "RF" means that the gas has been plasmafied by high-frequency power. In addition, "cycle count" is the number of repetitions of Steps S2 and S3 (i.e., M of Step S5). The same applies to Tables 2 to 8 described later.

[0123] FIGS. 6a to 6c show SEM images of a substrate (W-1) according to Example 1. As shown in FIG. 6a, liquid (L-1) was supplied to the concave portion (Wb-1) by step S2. The amount of liquid (L-1) supplied was such that it entered the interior of the concave portion (Wb-1). In addition, as shown in FIG. 6b, when the processing was stopped during step S3, specifically when the processing time of step S3 was 10 seconds, a similar appearance to FIG. 2c was observed, that is, the liquid (L-1) was seen rising from the concave portion (Wb-1) toward the convex normal surface (Wd-1). In addition, as shown in FIG. 6c, a film (W5-1) was selectively formed on the convex normal surface (Wd-1) by step S3.

[0124] FIGS. 7a and 7b show SEM images of a substrate (W-2) according to Example 2. As shown in FIG. 7a, liquid (L-2) was supplied to the concave portion (Wb-2) by step S2. In Example 2, the processing time of step S2 was longer than in Example 1, so the amount of liquid (L-2) supplied was large; thus, liquid (L-2) was supplied not only to the concave portion (Wb-2) but also to the convex normal surface (Wd-2). Additionally, as shown in FIG. 7b, a film (W5-2) was selectively formed on the convex normal surface (Wd-2) by step S3.

[0125] <Example 3>

[0126] In Example 3, using the film formation device (1) shown in FIG. 5, steps S1 to S2 were performed under the processing conditions shown in Table 2, and then steps S3 to S8 were not performed, and step S9 was performed under the processing conditions shown in Table 2. In step S9, only Ar gas was supplied into the processing vessel (2), and the change in the liquid (L) in the concave portion (Wb) was observed.

[0127]

[0128] Figure 8 shows the relationship between the processing time of Step S9 of Example 3 and the thickness of the liquid (L) in the depression (Wb). As is evident from Figure 8, no movement or reduction of the liquid (L) in the depression (Wb) was observed even when left for a long time under a reduced pressure atmosphere. This means that no movement of the liquid (L) occurs until the reaction between the liquid (L) and the processing gas (G) begins, and that the liquid (L) is difficult to evaporate because it has strong intermolecular forces and strong cohesive forces.

[0129] <Examples 4 to 7>

[0130] In Examples 4 to 7, steps S1 to S3 and S5 were performed using the film formation device (1) shown in FIG. 5 under the processing conditions shown in Table 3, and steps S4 and S6 to S8 were not performed.

[0131]

[0132] Figure 9a shows an SEM image of the substrate (W-4) after processing according to Example 4. In Example 4, steps S2 and S3 were performed once each, as in Example 1. As a result, among the concave portion (Wb-4) and the convex portion normal surface (Wd-4), a film (W5-4) was selectively formed on the convex portion normal surface (Wd-4).

[0133] Figure 9b shows an SEM image of the substrate (W-5) after processing for Example 5. In Example 5, unlike Example 1, steps S2 and S3 were performed 10 times each. As a result, among the concave portion (Wb-5) and the convex normal surface (Wd-5), a film (W5-5) was selectively formed on the convex normal surface (Wd-5).

[0134] FIG. 9c shows an SEM image of the substrate (W-6) after processing for Example 6. In Example 6, unlike Example 1, H2O gas was supplied into the processing vessel (2) instead of O2 gas in step S3. As a result, among the concave portion (Wb-6) and the convex portion normal surface (Wd-6), a film (W5-6) was selectively formed on the convex portion normal surface (Wd-6).

[0135] FIG. 9d shows an SEM image of the substrate (W-7) after processing for Example 7. In Example 7, unlike Example 1, N2 gas was supplied into the processing vessel (2) instead of O2 gas in step S3. Additionally, the N2 gas was plasmafied. As a result, among the concave portion (Wb-7) and the convex portion normal surface (Wd-7), a film (W5-7) was selectively formed on the convex portion normal surface (Wd-7).

[0136] As is evident from Examples 4 to 7, by using various types of processing gas (G), a film (W5) could be selectively formed on the normal surface (Wd) of the convex portion.

[0137] <Examples 8 to 12>

[0138] In Examples 8 to 12, steps S1 to S3 and S5 were performed using the film formation device (1) shown in FIG. 5 under the processing conditions shown in Table 4, and steps S4 and S6 to S8 were not performed.

[0139]

[0140] Figure 10a shows an SEM image of the substrate (W-8) after processing according to Example 8. In Example 8, steps S2 and S3 were performed once each under the same conditions as Example 4, except that the material of the convex normal surface and the concave bottom surface was changed to titanium oxide (TiO2). As a result, among the concave portion (Wb-8) and the convex normal surface (Wd-8), a film (W5-8) was selectively formed on the convex normal surface (Wd-8).

[0141] FIG. 10b shows an SEM image of the substrate (W-9) after processing according to Example 9. In Example 9, steps S2 and S3 were performed once each under the same conditions as Example 4, except that the material of the convex normal surface and the concave bottom surface was changed to silicon nitride (SiN). As a result, among the concave portion (Wb-9) and the convex normal surface (Wd-9), a film (W5-9) was selectively formed on the convex normal surface (Wd-9).

[0142] FIG. 10c shows an SEM image of the substrate (W-10) after processing according to Example 10. In Example 10, steps S2 and S3 were performed once each under the same conditions as Example 4, except that the material of the convex normal surface and the concave bottom surface was changed to silicon (Si). As a result, among the concave portion (Wb-10) and the convex normal surface (Wd-10), a film (W5-10) was selectively formed on the convex normal surface (Wd-10).

[0143] Figure 11a shows an SEM image of the substrate (W-11) after processing according to Example 11. In Example 11, steps S2 and S3 were performed once each under the same conditions as Example 4, except that the material of the convex normal surface and the concave bottom surface was changed to carbon (C). As a result, among the concave portion (Wb-11) and the convex normal surface (Wd-11), a film (W5-11) was selectively formed on the convex normal surface (Wd-11).

[0144] Figure 11b shows an SEM image of the substrate (W-12) after processing according to Example 12. In Example 12, steps S2 and S3 were performed once each under the same conditions as Example 4, except that the material of the normal surface of the convex portion was changed to ruthenium (Ru). As a result, among the concave portion (Wb-12) and the normal surface of the convex portion (Wd-12), a film (W5-12) was selectively formed on the normal surface of the convex portion (Wd-12).

[0145] As is evident from Examples 8 to 12, a film (W5) could be selectively formed on the normal surface (Wd) of the convex portion using a substrate (W) of various materials.

[0146] <Examples 13 to 14>

[0147] In Examples 13 to 14, steps S1 to S3 and S5 were performed using the film formation device (1) shown in FIG. 5 under the processing conditions shown in Table 5, and steps S4 and S6 to S8 were not performed.

[0148]

[0149] Figure 12a shows an SEM image of the substrate (W-13) after processing according to Example 13. In Example 13, steps S2 and S3 were performed once each under the same conditions as Example 4, except that the substrate temperature was changed to 80°C. As a result, among the concave portion (Wb-13) and the convex portion normal surface (Wd-13), a film (W5-13) was selectively formed on the convex portion normal surface (Wd-13).

[0150] FIG. 12b shows an SEM image of the substrate (W-14) after processing according to Example 14. In Example 14, steps S2 and S3 were performed once each under the same conditions as Example 4, except that the substrate temperature was changed to 200°C. As a result, among the concave portion (Wb-14) and the convex portion normal surface (Wd-14), a film (W5-14) was selectively formed on the convex portion normal surface (Wd-14).

[0151] As is evident from Examples 13 to 14, a film (W5) could be selectively formed on the normal surface (Wd) of the convex portion at various substrate temperatures.

[0152] <Examples 15 to 16>

[0153] In Example 15, steps S1 to S3 and S5 were performed under the processing conditions shown in Table 6 using the film forming device (1) shown in FIG. 5, and steps S4 and S6 to S8 were not performed. Meanwhile, in Example 16, steps S1 to S5 were performed under the processing conditions shown in Table 6 using the film forming device (1) shown in FIG. 5, and steps S6 to S8 were not performed.

[0154]

[0155] In Example 15, the film (W5) formed on the convex normal surface (Wd) was etched with an aqueous solution having an HF concentration of 0.5 mass%, and the etching rate was 762.8 Å / min. Meanwhile, in Example 16, the film (W5) formed on the convex normal surface (Wd) was etched with an aqueous solution having an HF concentration of 0.5 mass%, and the etching rate was 81.3 Å / min. Therefore, the film (W5) could be modified by step S5.

[0156] <Example 17>

[0157] In Example 17, steps S1 to S3 and S5 were performed using the film formation device (1) shown in FIG. 5 under the processing conditions shown in Table 7, and steps S4 and S6 to S8 were not performed.

[0158]

[0159] FIG. 13 shows an SEM image of the substrate (W-17) after processing according to Example 17. In Example 17, unlike Example 1, Si2Cl6 (HCD) was supplied into the processing vessel (2) as a raw material gas instead of TiCl4 in Step S2. Also, in Step S3, Ar gas and O2 gas were plasma-formed. Also, Steps S2 and S3 were performed twice each. Additionally, the material of the convex normal surface and the concave bottom surface was changed to TiO2. As a result, among the concave portion (Wb-17) and the convex normal surface (Wd-17), a film (W5-17) was selectively formed on the convex normal surface (Wd-17). Also, the same result was obtained when the material of the convex normal surface and the concave bottom surface was changed to SiO2.

[0160] <Example 18>

[0161] In Example 18, steps S1 to S3 and S5 were performed using the film formation device (1) shown in FIG. 5 under the processing conditions shown in Table 8, and steps S4 and S6 to S8 were not performed.

[0162]

[0163] FIG. 14 shows an SEM image of the substrate (W-18) after processing for Example 18. In Example 18, unlike Example 1, SnCl4 was supplied into the processing vessel (2) instead of TiCl4 as the source gas in step S2. As a result, among the concave portion (Wb-18) and the convex portion normal surface (Wd-18), a film (W5-18) was selectively formed on the convex portion normal surface (Wd-18).

[0164] As is evident from Examples 17 to 18, a film (W5) could be selectively formed on the normal surface (Wd) of the convex portion using various raw gases.

[0165] <Example 19>

[0166] In Example 19, four substrates (W) with different initial depths (A0) were prepared. The initial depths (A0) of the four prepared substrates (W) were 8 nm, 12 nm, 18 nm, and 150 nm. For the substrates (W) with an initial depth (A0) of 8 nm, 12 nm, or 18 nm, concave and convex portions were formed by etching the silicon wafer. Meanwhile, for the substrate with an initial depth (A0) of 150 nm, a SiN film and a Si film were formed in sequence on the surface of the silicon wafer, and concave and convex portions were formed by etching the Si film. The SiN film was made to function as an etching stopper film to stop the etching.

[0167] In Example 19, steps S1 to S5 were performed using the film-forming device (1) shown in FIG. 5, and steps S6 to S8 were not performed. In Example 19, a first cycle consisting of steps S2 to S4 was performed 12 times (M=12) under the processing conditions shown in Table 9.

[0168]

[0169] In Table 9, "○" for various gases indicates that various gases have been supplied, and "ON" for "RF" indicates that the gas has been plasmafied by high-frequency power. The same applies to Tables 10 to 12 and Table 14 described later.

[0170] FIGS. 15a to 15d show SEM images of four substrates (W) obtained in Example 19. In FIGS. 15a to 15d, W1 is a silicon wafer and W2 is a film formed by the first cycle. Also, in FIG. 15d, W3 is a SiN film and W4 is a Si film.

[0171] As illustrated in FIGS. 15a to 15c, when the initial depth (A0) is 20 nm or less, a film (W2) is formed on the bottom surface of the concave part and on the side surface of the concave part, but the thickness of the film (W2) on the top surface of the convex part is thicker than the thickness of the film (W2) on the bottom surface of the concave part, so the step difference on the substrate surface is expanded by the first cycle. Also, as illustrated in FIG. 15c, there were cases where a protrusion formed on the bottom surface of the concave part.

[0172] Meanwhile, as shown in FIG. 15d, when the initial depth (A0) exceeds 100 nm, the film (W2) is selectively formed on the convex normal surface with respect to the bottom surface and side surface of the concave portion. The step height of the substrate surface is expanded by the first cycle.

[0173] <Example 20>

[0174] In Example 20, three substrates (W) with different initial depths (A0) were prepared. The initial depths (A0) of the three prepared substrates (W) were 8 nm, 12 nm, and 18 nm. These substrates (W) formed concave and convex portions by etching a silicon wafer.

[0175] In Example 20, steps S1 to S7 were performed using the film-forming device (1) shown in FIG. 5, and step S8 was not performed. In Example 20, the second cycle was performed once (N=1) under the processing conditions shown in Table 10. The second cycle consisted of 12 first cycles (M=12) and step S6 performed after the 12 first cycles. The first cycle consisted of steps S2 to S4.

[0176]

[0177] FIGS. 16a to 16c show SEM images of three substrates (W) obtained in Example 20. In FIGS. 16a to 16c, W1 is a silicon wafer, and W2 is a film formed by the second cycle.

[0178] As shown in FIGS. 16a to 16c, when the initial depth (A0) is 20 nm or less, a film (W2) is formed on the bottom surface of the concave part and on the side surface of the concave part, but the thickness of the film (W2) on the top surface of the convex part is thicker than the thickness of the film (W2) on the bottom surface of the concave part, and the step difference on the substrate surface is expanded by the second cycle.

[0179] In addition, as is evident from comparing FIG. 16c and FIG. 15c, it can be seen that by performing step S6, the width of the concave portion can be expanded and the protrusion on the bottom surface of the concave portion can be removed.

[0180] <Example 21>

[0181] In Example 21, three substrates (W) with different initial depths (A0) were prepared. The initial depths (A0) of the three prepared substrates (W) were 8 nm, 12 nm, and 18 nm. These substrates (W) formed concave and convex portions by etching a silicon wafer.

[0182] In Example 21, steps S1 to S7 were performed using the membrane device (1) shown in FIG. 5, and step S8 was not performed. In Example 21, the second cycle was performed twice (N=2) under the processing conditions shown in Table 11. The second cycle consisted of 12 first cycles (M=12) and step S6 performed after the 12 first cycles. The first cycle consisted of steps S2 to S4.

[0183]

[0184] FIGS. 17a to 17c show SEM images of three substrates (W) obtained in Example 21. In FIGS. 17a to 17c, W1 is a silicon wafer, and W2 is a film formed by the second cycle.

[0185] As shown in FIGS. 17a to 17c, when the initial depth (A0) is 20 nm or less, a film (W2) is formed on the bottom surface of the concave part and on the side surface of the concave part, but the thickness of the film (W2) on the top surface of the convex part is thicker than the thickness of the film (W2) on the bottom surface of the concave part, so the step difference on the substrate surface is expanded by the second cycle.

[0186] In addition, as is evident from comparing FIG. 17c and FIG. 15c, it can be seen that by performing step S6, the width of the concave portion can be expanded and the protrusion on the bottom surface of the concave portion can be removed.

[0187] <Example 22>

[0188] In Example 22, four substrates (W) with different initial depths (A0) were prepared. The initial depths (A0) of the four prepared substrates (W) were 8 nm, 12 nm, 18 nm, and 150 nm. For the substrates (W) with an initial depth (A0) of 8 nm, 12 nm, or 18 nm, concave and convex portions were formed by etching the silicon wafer. Meanwhile, for the substrate with an initial depth (A0) of 150 nm, a SiN film and a Si film were formed in sequence on the surface of the silicon wafer, and concave and convex portions were formed by etching the Si film. The SiN film was made to function as an etching stopper film to stop the etching.

[0189] In Example 22, steps S1 to S7 were performed using the membrane device (1) shown in FIG. 5, and step S8 was not performed. In Example 22, the second cycle was performed three times (N=3) under the processing conditions shown in Table 12. The second cycle consisted of 12 first cycles (M=12) and step S6 performed after the 12 first cycles. The first cycle consisted of steps S2 to S4.

[0190]

[0191] FIGS. 18a to 18d show SEM images of four substrates (W) obtained in Example 22. In FIGS. 18a to 18d, W1 is a silicon wafer and W2 is a film formed by the second cycle. Also, in FIG. 18d, W3 is a SiN film and W4 is a Si film.

[0192] As shown in FIGS. 18a to 18c, when the initial depth (A0) is 20 nm or less, a film (W2) is formed on the bottom surface of the concave part and on the side surface of the concave part, but the thickness of the film (W2) on the top surface of the convex part is thicker than the thickness of the film (W2) on the bottom surface of the concave part, and the step difference on the substrate surface is expanded by the second cycle.

[0193] In addition, as is evident from comparing FIG. 18c and FIG. 15c, it can be seen that by performing step S6, the width of the concave portion can be expanded and the protrusion on the bottom surface of the concave portion can be removed.

[0194] Meanwhile, as shown in FIG. 18d, when the initial depth (A0) exceeds 100 nm, the film (W2) is selectively formed on the convex normal surface with respect to the bottom surface of the concave part and the side surface of the concave part. With the SiN film (W3) exposed on the bottom surface of the concave part, the step of the substrate surface is expanded by the second cycle.

[0195] <Step difference of the substrate obtained in Examples 19 to 22>

[0196] Table 13 shows a comparison of the step size of the substrates obtained in Examples 19 to 22 (wherein the initial depth of the concave portion (Wb) in all Examples 19 to 22 is 18 nm). The step size is indicated by the depth (A) of the concave portion (Wb).

[0197]

[0198] As is evident from comparing Examples 20 to 22 in Table 13, it can be seen that by repeating the second cycle, the step height can be expanded while maintaining the width (B) of the concave portion (Wb). Additionally, the step height in Example 20 is smaller than that in Example 19 because the film (W2) was etched in Example 20.

[0199] <Example 23>

[0200] In Example 23, steps S1 to S3 and S5 were performed using the film deposition apparatus (1) shown in FIG. 5 under the processing conditions shown in Table 14, and steps S4 and S6 to S8 were not performed. In Example 23, before introducing the substrate (W) into the processing vessel (2) shown in FIG. 5, concave and convex portions were formed in advance on the surface (Wa) of the substrate. Specifically, as shown in FIG. 19a and 19b, the concave and convex portions were formed by selectively etching the SiO2 layer (W1a) among the SiO2 layer (W1a) and the SiN layer (W1b). The initial depth of the concave portion was 30 nm.

[0201]

[0202] FIGS. 19a and 19b show SEM images of a substrate according to Example 23. As shown in FIG. 19a, a liquid (L) was supplied to the substrate surface (Wa) by step S2. The liquid (L) covered not only the concave parts but also the convex parts, so the liquid surface of the liquid (L) was horizontal. As shown in FIG. 19b, when step S3 was performed following step S2, the liquid (L) flowed to expand the step, and a film (W2) was formed from the liquid (L). Thus, it can be seen that the step can be expanded even if step S3 is performed only once.

[0203] Regarding the above embodiment, the following supplementary information is disclosed.

[0204] [Appendix 1]

[0205] (A) supplying a liquid to the surface of a substrate having adjacent concave and convex portions on its surface, and

[0206] (B) supplying a treatment gas that chemically changes the liquid to the surface of the substrate, thereby moving the liquid from the concave portion to the convex portion by means of a reaction between the liquid and the treatment gas, and forming a film on the normal surface of the convex portion to expand the step difference of the surface, and

[0207] (C) A method for forming a film having etching a portion of the above film.

[0208] [Book 2]

[0209] A method for forming a membrane as described in Appendix 1, comprising performing a first cycle including the above (A) and the above (B) M times (M is an integer greater than or equal to 1), and performing the above (C) after the above M times of the first cycle.

[0210] [Book 3]

[0211] A method for forming a membrane as described in Appendix 2, comprising performing the above-mentioned first cycle M times and the above-mentioned second cycle (C) performed after the above-mentioned first cycle N times (N is an integer greater than or equal to 1).

[0212] [Book 4]

[0213] A film formation method described in Appendix 3, comprising performing the above second cycle N times, and then etching the film to expose a material different from the film on the bottom surface of the concave portion.

[0214] [Book 5]

[0215] A film formation method described in any one of Appendix 1 to 4, wherein, prior to carrying out the above (A), the step formed on the surface of the substrate is 20 nm or less.

[0216] [Book 6]

[0217] The above liquid is a halogenated film forming method described in any one of Appendix 1 to 5.

[0218] [Book 7]

[0219] The above (A) is a film formation method described in Appendix 6, comprising forming the liquid by a reaction between a source gas that is a source of the above halide and a reaction gas that reacts with the above source gas.

[0220] [Book 8]

[0221] The above liquid is a liquid polymer, a film formation method described in any one of Appendix 1 to 5.

[0222] [Book 9]

[0223] The above liquid is synthesized in a processing vessel that accommodates the substrate and supplied to the concave portion of the substrate, a film formation method described in Appendix 8.

[0224] [Book 10]

[0225] A film formation method described in any one of Appendix 1 to 9, wherein the treatment gas that chemically changes the liquid in (B) above comprises an element introduced into the liquid.

[0226] [Book 11]

[0227] The treatment gas that chemically changes the above liquid comprises an oxygen-containing gas, a film formation method described in Appendix 10.

[0228] [Book 12]

[0229] The treatment gas that chemically changes the above liquid comprises a nitrogen-containing gas, a film formation method described in Appendix 10.

[0230] [Appendix 13]

[0231] The treatment gas that chemically changes the above liquid comprises a hydride gas, a film formation method described in Appendix 10.

[0232] [Book 14]

[0233] The treatment gas that chemically changes the liquid degasses the elements constituting the liquid, a film formation method described in any one of Appendix 1 to 9.

[0234] [Book 15]

[0235] The treatment gas that chemically changes the above liquid comprises a reducing gas, a film formation method described in Appendix 14.

[0236] [Appendix 16]

[0237] The above reducing gas is hydrogen gas or deuterium gas, a method for forming a film as described in Appendix 15.

[0238] [Appendix 17]

[0239] The above (B) is a film formation method described in any one of Appendix 1 to 16, comprising plasmaizing the treatment gas that chemically changes the liquid.

[0240] [Appendix 18]

[0241] The above (C) is a film formation method described in any one of Appendix 1 to 17, comprising etching a portion of the film with an etching gas.

[0242] [Appendix 19]

[0243] A method for forming a membrane as described in any one of Appendix 1 to 18, comprising modifying the membrane after (B) and before (C).

[0244] Although embodiments of the film-forming method and film-forming apparatus according to the present disclosure have been described above, the present disclosure is not limited to the above embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope described in the claims. These also naturally fall within the technical scope of the present disclosure.

[0245] This application claims priority based on Japanese Patent Application No. 2021-093209 filed with the Japan Patent Office on June 2, 2021, and incorporates the entire contents of Japanese Patent Application No. 2021-093209 into this application. Explanation of the symbols

[0246] W: Substrate Wa: Surface Wb: Concave part Wc: Convex part W2: Mark L: Liquid

Claims

Claim 1 A film formation method comprising: (A) supplying a liquid to the surface of a substrate having adjacent concave and convex portions on its surface; (B) supplying a treatment gas that chemically changes the liquid to the surface of the substrate, thereby moving the liquid from the concave portion to the convex portion by utilizing the change in surface tension caused by the reaction between the liquid and the treatment gas, and forming a film on the normal surface of the convex portion to expand the step of the surface; and (C) etching a portion of the film. Claim 2 A method for forming a membrane according to claim 1, wherein a first cycle including the above (A) and the above (B) is performed M times (M is an integer greater than or equal to 1), and the above (C) is performed after the above M times of the first cycle. Claim 3 A method of forming a membrane according to paragraph 2, wherein the first cycle is performed M times and the second cycle (C) is performed after the first cycle N times (N is an integer greater than or equal to 1). Claim 4 A film formation method according to claim 3, comprising, after performing the second cycle N times, further etching the film to expose a material different from the film on the bottom surface of the concave portion. Claim 5 A film formation method according to claim 1, wherein, prior to performing (A), the step formed on the surface of the substrate is 20 nm or less. Claim 6 In claim 1, the liquid is a halide, a film formation method. Claim 7 In claim 6, the above (A) is a method for forming a film, comprising forming the liquid by a reaction between a raw material gas that is a raw material for the halide and a reaction gas that reacts with the raw material gas. Claim 8 A film formation method according to claim 1, wherein the liquid is a polymer in a liquid state. Claim 9 A film formation method according to claim 8, wherein the liquid is synthesized in a processing vessel containing the substrate and supplied to the concave portion of the substrate. Claim 10 A method for forming a film according to claim 1, wherein the treatment gas that chemically changes the liquid in (B) comprises an element introduced into the liquid. Claim 11 In claim 10, the treatment gas that chemically changes the liquid comprises an oxygen-containing gas, in a film formation method. Claim 12 In claim 10, the treatment gas that chemically changes the liquid comprises a nitrogen-containing gas, in a film formation method. Claim 13 In claim 10, the treatment gas that chemically changes the liquid comprises a hydride gas, in a film formation method. Claim 14 A film formation method according to claim 1, wherein the treatment gas that chemically changes the liquid degass the elements constituting the liquid. Claim 15 In claim 14, the treatment gas that chemically changes the liquid comprises a reducing gas, in a film formation method. Claim 16 In paragraph 15, the reducing gas is hydrogen gas or deuterium gas, a method for forming a film. Claim 17 A method for forming a film according to claim 1, wherein (B) comprises plasmaizing the treatment gas that chemically changes the liquid. Claim 18 A film formation method according to claim 1, wherein (C) comprises etching a portion of the film with an etching gas. Claim 19 A method for forming a film according to claim 1, comprising modifying the film after (B) and before (C). Claim 20 A film formation apparatus comprising: a processing vessel; a holding support member that horizontally holds and supports a substrate by having a surface including adjacent concave and convex portions facing upward within the processing vessel; a gas supply member that supplies a source gas, a reaction gas that reacts with the source gas, a processing gas that chemically changes a liquid formed by the reaction of the source gas and the reaction gas, and an etching gas to the surface of the substrate held and supported by the holding support member; and a control member that controls the gas supply member. The control member performs the following: (A) supplying a liquid formed by the reaction of the source gas and the reaction gas to the surface of the substrate; (B) supplying the processing gas to the surface of the substrate to move the liquid from the concave portion to the convex portion by utilizing a change in surface tension generated by the reaction of the liquid and the processing gas to form a film on the normal surface of the convex portion, thereby expanding the step difference of the surface; and (C) etching a portion of the film with the etching gas.

Images