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

Abstract

To provide a substrate processing apparatus and a substrate processing method that suppress surface oxidation of substrates by controlling the concentration of dissolved oxygen in the processing solution.SOLUTION: A substrate processing apparatus according to one embodiment has a processing tank capable of storing an agent and immersing a substrate in the agent for processing, a holding member that holds the substrate, and a lid positioned over the processing tank and provided inside with a first bubble discharge tube that discharges gas. A surface of the lid on the side of the processing tank may be in contact with the agent, and the first bubble discharge tube may discharge gas into the agent.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a substrate processing apparatus and a substrate processing method. [Background technology]

[0002] Substrate processing equipment is used to perform various processes such as etching and substrate cleaning on various substrates such as semiconductor wafers, glass substrates for photomasks, substrates for displays, substrates for optical disks, etc. There are two types of substrate processing equipment: batch type, which processes multiple substrates simultaneously, and single wafer type, which processes individual substrates. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 10,796,948 [Patent Document 2] U.S. Patent No. 11,088,164 [Patent Document 3] U.S. Patent No. 10,845,609 [Patent Document 4] U.S. Patent No. 10,423,066 [Patent Document 5] U.S. Patent No. 10,153,176 Summary of the Invention [Problem to be solved by the invention]

[0004] An embodiment according to the present disclosure provides a substrate processing apparatus and a substrate processing method that suppresses surface oxidation of a substrate by suppressing the dissolved oxygen concentration in a processing solution. [Means for solving the problem]

[0005] A substrate processing apparatus according to one embodiment includes a processing tank capable of storing chemicals and processing a substrate by immersing it in the chemicals, a holding member for holding the substrate, and a lid disposed above the processing tank and having a first bubble discharge pipe disposed therein for discharging gas. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a diagram schematically illustrating a substrate processing apparatus according to an embodiment. [Figure 2] 1 is a top view schematically showing a structure of a substrate processing apparatus according to an embodiment; [Figure 3] 1A to 1C are views schematically illustrating a substrate processing method according to an embodiment. [Figure 4] 1A to 1C are views schematically illustrating a substrate processing method according to an embodiment. [Figure 5] 1 is a diagram schematically illustrating a substrate processing apparatus according to an embodiment. [Figure 6] 1 is a top view schematically showing a structure of a substrate processing apparatus according to an embodiment; [Figure 7] 1A to 1C are views schematically illustrating a substrate processing method according to an embodiment. [Figure 8] 1A to 1C are views schematically illustrating a substrate processing method according to an embodiment. [Figure 9] 10A to 10C are views schematically showing a substrate processing method according to a modified example. [Figure 10] 10A to 10C are views schematically showing a substrate processing method according to a modified example. [Figure 11] 1 is a diagram schematically illustrating a substrate processing apparatus according to an embodiment. [Figure 12] 1A to 1C are views schematically illustrating a substrate processing method according to an embodiment. [Figure 13] 1 is a diagram schematically illustrating a substrate processing apparatus according to an embodiment. [Figure 14] 1 is a top view schematically showing a structure of a substrate processing apparatus according to an embodiment; [Figure 15] 1 is a diagram schematically illustrating a substrate processing apparatus according to an embodiment. [Figure 16]10A to 10C are views schematically showing a substrate processing method according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0007] The substrate processing apparatus and substrate processing method according to the present embodiment will be described in detail below with reference to the drawings. In the following description, elements having substantially the same functions and configurations are designated by the same reference numerals or reference numerals with an alphabetical suffix, and will be described repeatedly only when necessary. The following embodiments exemplify apparatuses and methods for embodying the technical ideas of the embodiments. Various modifications can be made to the embodiments without departing from the spirit of the invention. These embodiments and their variations are included within the scope of the invention set forth in the claims and their equivalents.

[0008] In order to clarify the description, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. In this specification and each drawing, elements having the same functions as those explained with reference to the previous drawings may be assigned the same reference numerals, and duplicate explanations may be omitted.

[0009] In this specification, unless otherwise specified, an expression such as "α includes A, B, or C" does not exclude the case where α includes multiple combinations of A to C. Furthermore, these expressions do not exclude the case where α includes other elements.

[0010] In this specification, the term "horizontal" may refer to a direction (XY direction) that is horizontal with respect to the bottom surface of the processing tank of the substrate processing apparatus, and the term "vertical" may refer to a direction (Z direction) that is approximately perpendicular to the horizontal direction.

[0011] The following embodiments can be combined with each other unless a technical contradiction occurs.

[0012] In the following embodiments, a semiconductor substrate such as a silicon wafer is used as an example of the substrate, but the technology of the present disclosure can be applied to substrates other than semiconductor substrates, such as glass substrates for photomasks, substrates for displays, and substrates for optical disks.

[0013] First Embodiment [Configuration of substrate processing equipment] FIG. 1 is a diagram schematically illustrating the overall configuration of a substrate processing apparatus according to an embodiment. FIG. 2 is a top view schematically illustrating the structure of the substrate processing apparatus according to an embodiment. The substrate processing apparatus 1 according to this embodiment is a wet etching processing apparatus that partially removes, for example, metal wiring (not shown in FIG. 1) provided on a substrate S using a solution L of an inorganic acid such as sulfuric acid, nitric acid, hydrochloric acid, or hydrofluoric acid, or an organic acid such as acetic acid or citric acid. However, the present invention is not limited thereto, and the wet etching can also be applied to, for example, partially removing silicon provided on the substrate S using a solution L containing hydrogen peroxide. As shown in FIG. 1, the substrate processing apparatus 1 includes a processing tank 10, a holding member 20, and a lid 30.

[0014] The processing tank 10 is formed in a box shape with an upper opening 11. The processing tank 10 stores a solution L, i.e., an etching liquid (processing liquid, chemical), inside. The type, temperature, and concentration of the solution L stored inside the processing tank 10 are optimized for etching the substrate S. A solution supply path 12 is connected to the bottom of the processing tank 10. The solution supply path 12 supplies the solution L to the processing tank 10. The solution supply path 12 has a solution discharge port that supplies the solution L to the processing tank 10. The shape of the solution discharge port is not particularly limited. It is preferable that the solution discharge port be located below the holding member 20 that holds the substrate S.

[0015] The processing tank 10 can accommodate wafer-shaped (disc-shaped) substrates S vertically (with the main surface in the XZ direction). For example, up to 50 substrates S may be accommodated in one processing tank 10. Although FIG. 1 shows one substrate S in the processing tank 10, multiple substrates S can be accommodated lined up in the depth direction (Y direction) of the page. The processing tank 10 has a depth sufficient to completely immerse the substrates S accommodated vertically in the solution L. The upper opening 11 of the processing tank 10 is higher than the upper end of the substrates S accommodated vertically.

[0016] Although not shown in the figure, the treatment tank 10 may further have an outer tank. The outer tank may surround the entire upper end opening 11 of the treatment tank 10. The outer tank can collect the solution L that overflows from the upper end opening 11 of the treatment tank 10.

[0017] Inside the processing tank 10, a holding member 20 holds a plurality of substrates S arranged in rows in the horizontal direction (Y direction) at predetermined intervals. The holding member 20 also includes a lifting mechanism that raises and lowers the held substrates S in the vertical direction (Z direction) relative to the processing tank 10. By the lifting action of the lifting mechanism, the substrates S before etching can be automatically immersed in the solution L stored in the processing tank 10, and the substrates S after etching can be automatically removed from the processing tank 10.

[0018] A lid 30 is provided on top of the treatment tank 10. The lid 30 is made up of two flat plate-shaped members and has a double-hinged structure that opens and closes by rotating from the center in opposite directions (left and right directions on the page) around one side of the top opening 11 and the other side opposite it as an axis 31. However, the lid 30 is not limited to this, and the lid 30 may be a single-hinged structure that opens and closes by rotating from the other side opposite it to the one side as an axis. The lid 30 covers the top opening 11 of the treatment tank 10. The lid 30 may have a gap in the center to the extent that the left and right lids do not interfere with each other.

[0019] As shown in FIGS. 1 and 2, the lid 30 is provided with a first bubble discharge pipe 32. The first bubble discharge pipe 32 is provided inside the lid 30. The first bubble discharge pipe 32 supplies gas G into the treatment tank 10. The first bubble discharge pipe 32 is provided with a plurality of first bubble discharge ports 33 that supply gas G to the treatment tank 10. The plurality of first bubble discharge ports 33 are arranged on the underside of the lid 30 (the surface facing the treatment tank 10). The gas G is discharged from the first bubble discharge ports 33 into the space above the solution L stored in the treatment tank 10. Note that in FIG. 2, the plurality of first bubble discharge ports 33 are evenly arranged in a matrix on the underside of the lid 30. However, the number and arrangement of the first bubble discharge ports 33 are not particularly limited as long as the gas G can be evenly supplied to the liquid surface of the solution L.

[0020] The gas G supplied from the first bubble discharge pipe 32 may be, for example, a gas containing nitrogen. However, the present invention is not limited to this, and the gas G may be any inert gas. The first bubble discharge ports 33 are preferably arranged evenly with respect to the liquid surface of the solution L. In this case, each first bubble discharge port 33 may supply gas G at approximately the same flow rate to the processing tank 10. However, the present invention is not limited to this, and each first bubble discharge port 33 may supply gas G at different flow rates to the processing tank 10 depending on its arrangement relative to the substrate S or the lid 30.

[0021] The substrate processing apparatus 1 according to this embodiment supplies gas G from the first bubble outlet 33 to the space above the solution L stored in the processing tank 10, thereby preventing oxygen from the atmosphere from dissolving through the liquid surface of the solution L and reducing the amount of dissolved oxygen in the solution L during the etching process. This improves the uniformity of the etching rate within the substrate S and prevents surface oxidation of the substrate S.

[0022] [Substrate processing method] A substrate processing method using the substrate processing apparatus 1 according to this embodiment will be described below. The substrate processing method according to this embodiment is, for example, a wet etching method for partially removing metal wiring (not shown in FIG. 1) provided on a substrate S with a solution L of an inorganic acid such as sulfuric acid, nitric acid, hydrochloric acid, or hydrofluoric acid, or an organic acid such as acetic acid or citric acid. However, the present invention is not limited to this, and can also be applied to a wet etching method for partially removing silicon provided on the substrate S with a solution L containing hydrogen peroxide, for example. FIGS. 3 and 4 are diagrams schematically showing a substrate processing method according to one embodiment.

[0023] As shown in FIG. 3, first, the substrate S is placed on the holding member 20 so that it is vertical (the main surface is oriented in the XZ direction). The substrate S is, for example, a semiconductor substrate such as a silicon wafer. Inside the processing tank 10, a solution L is stored up to the upper end opening 11 from the solution supply channel 12. Before immersing the substrate S in the processing tank 10, gas G may be supplied to the liquid surface of the solution L from the first bubble discharge port 33 to remove dissolved oxygen in advance. It is desirable to discharge the gas G for 5 minutes or more before processing. The holding member 20 holding the substrate S is immersed in the solution L stored in the processing tank 10.

[0024] As shown in Fig. 4, the lid 30 is closed so as to cover the upper opening 11 of the processing tank 10. Since the lid 30 is placed on the upper opening 11, it does not come into contact with the solution L. The gas G is, for example, a gas containing nitrogen. The gas G is discharged from the first bubble discharge port 33 into the space above the solution L stored in the processing tank 10.

[0025] In the substrate processing method using the substrate processing apparatus 1 according to this embodiment, by supplying gas G from the first bubble outlet 33 to the space above the solution L stored in the processing tank 10, it is possible to prevent oxygen from the atmosphere from dissolving into the solution L from the liquid surface, thereby reducing the amount of dissolved oxygen in the solution L during the etching process. This makes it possible to improve the uniformity of the etching rate within the substrate S and to prevent surface oxidation of the substrate S.

[0026] Second Embodiment The configuration of the substrate processing apparatus according to this embodiment is the same as that of the substrate processing apparatus according to the first embodiment, except for the shape and arrangement of the lid. Explanations of the same things as in the first embodiment will be omitted, and only the parts that differ from the configuration of the substrate processing apparatus according to the first embodiment will be described here.

[0027] [Configuration of substrate processing equipment] Fig. 5 is a diagram schematically illustrating the overall configuration of a substrate processing apparatus according to an embodiment. Fig. 6 is a top view schematically illustrating the structure of a substrate processing apparatus according to an embodiment. As shown in Fig. 5, the substrate processing apparatus 1a includes a processing tank 10a, a holding member 20a, and a lid 30a.

[0028] A lid 30a is provided on the treatment tank 10a. The lid 30a is composed of two members and has a double-hinged structure that opens and closes by rotating from the center in opposite directions (left and right directions on the paper) around one side of the upper opening 11a and the other side opposite to it, as an axis 31a. However, the lid 30a is not limited to this, and the lid 30a may be a single-hinged structure that opens and closes by rotating from the other side opposite to it toward the first side, using one side of the upper opening 11a as an axis. The lid 30a has a gap between the two members. The lid 30a may be in contact with the inside of the treatment tank 10a on the side of axis 31a.

[0029] The lower surface of the lid 30a (the surface facing the treatment tank 10a) is positioned below the upper opening 11a of the treatment tank 10a and comes into contact with the solution L stored in the treatment tank 10a. The lower surface of the lid 30a (the surface facing the treatment tank 10a) is positioned within the treatment tank 10a at an angle relative to the horizontal (XY direction). In FIG. 5, the lower surface of the lid 30a (the surface facing the treatment tank 10a) is positioned so that the axis 31a side is lower in the vertical direction (Z direction) and the center side is higher in the vertical direction (Z direction). However, this is not limited thereto, and the lower surface of the lid 30a (the surface facing the treatment tank 10a) may be positioned so that the axis 31a side is higher in the vertical direction (Z direction) and the center side is lower in the vertical direction (Z direction) as long as there is no interference between the left and right lids or between the lid 30a and the treatment tank 10a. The inclination of the lower surface of the lid 30a (the surface on the treatment tank 10a side) with respect to the horizontal direction (XY direction) can be, for example, greater than 0° and equal to or less than 60°.

[0030] In FIG. 5, the lid 30a is made of a member having a different thickness in the vertical direction (Z direction). The lid 30a is configured so that the shaft 31a side is thicker in the vertical direction (Z direction) and the center side is thinner in the vertical direction (Z direction). The upper surface of the lid 30a (the surface opposite to the treatment tank 10a) is disposed in a substantially horizontal direction (XY direction) at the upper end opening 11a of the treatment tank 10a. However, this is not limited thereto, and the lid 30a may be made of a flat plate-like member having a substantially uniform thickness. In this case, the upper surface of the lid 30a (the surface opposite to the treatment tank 10a) may be disposed at an angle with respect to the horizontal direction (XY direction).

[0031] As shown in FIGS. 5 and 6, the lid 30a is provided with a first bubble discharge pipe 32a. The first bubble discharge pipe 32a is provided inside the lid 30a. The first bubble discharge pipe 32a supplies gas G into the treatment tank 10a. The first bubble discharge pipe 32a is provided with a plurality of first bubble discharge ports 33a that supply gas G to the treatment tank 10a. The plurality of first bubble discharge ports 33a are arranged on the underside of the lid 30a (the surface facing the treatment tank 10a). The gas G is discharged from the first bubble discharge ports 33a into the solution L stored in the treatment tank 10a.

[0032] In Figure 6, the multiple first bubble outlets 33a are arranged more on the axis 31a side of the lid 30a than on the central side. It is preferable to arrange the multiple first bubble outlets 33a in a lower area of ​​the lower surface of the lid 30a (the surface facing the processing tank 10a) in the vertical direction (Z direction) more than in a higher area. However, the number, size, and arrangement of the first bubble outlets 33a are not particularly limited. It is sufficient that the gas G can be supplied uniformly below the surface of the solution L.

[0033] The gas G supplied from the first bubble discharge pipe 32a may be, for example, a gas containing nitrogen. It is preferable that the first bubble discharge ports 33a are arranged in a region where the lower surface (the surface facing the processing tank 10a) of the lid 30a is lower in the vertical direction (Z direction) than in a region where the lower surface is higher in the vertical direction (Z direction). Each of the first bubble discharge ports 33a may supply gas G at approximately the same flow rate to the processing tank 10a. However, this is not a limitation, and each of the first bubble discharge ports 33a may supply gas G at different flow rates to the processing tank 10a depending on its position relative to the substrate S or the lid 30a.

[0034] With the above configuration, gas G supplied into the solution L in the region where the underside of the lid 30a (the surface facing the processing tank 10a) is lower in the vertical direction (Z direction) moves along the slope of the underside of the lid 30a (the surface facing the processing tank 10a) to the region where it is higher in the vertical direction (Z direction), and is discharged from the gap between the two components.

[0035] In the substrate processing apparatus 1a according to this embodiment, by supplying gas G from the first bubble outlet 33a into the solution L stored in the processing tank 10a, oxygen from the atmosphere that has dissolved into the solution L from the liquid surface can be replaced with gas G, thereby further reducing the amount of oxygen dissolved in the solution L. Furthermore, since the lid 30a is in contact with the liquid surface of the solution L, oxygen from the atmosphere can be prevented from dissolving into the solution L from the liquid surface, thereby reducing the amount of oxygen dissolved in the solution L during the etching process. This improves the uniformity of the etching rate within the substrate S and reduces surface oxidation of the substrate S.

[0036] [Substrate processing method 1] A substrate processing method using the substrate processing apparatus 1a according to this embodiment will be described below. The substrate processing method according to this embodiment is performed, for example, in the manufacture of semiconductor devices such as 3D NAND. Figures 7 and 8 are diagrams schematically showing the substrate processing method according to one embodiment.

[0037] As shown in FIG. 7, first, the substrate S is placed on the holding member 20a so that it is vertical (the main surface is in the XZ direction). Inside the processing tank 10a, the solution L is stored from the solution supply path 12a up to the upper end opening 11a. Before the substrate S is immersed in the processing tank 10a, gas G may be supplied to the liquid surface of the solution L from the first bubble discharge port 33a to remove dissolved oxygen in advance. It is desirable to discharge the gas G for 5 minutes or more before processing. The holding member 20a holding the substrate S is immersed in the solution L stored in the processing tank 10a.

[0038] As shown in FIG. 8, the lid 30a is closed so that the underside of the lid 30a (the side facing the treatment tank 10a) is inserted into the treatment tank 10a. Since the two parts of the lid 30a cannot be closed simultaneously, they are opened and closed one by one. The underside of the lid 30a (the side facing the treatment tank 10a) is positioned below the upper end opening 11a of the treatment tank 10a and therefore comes into contact with the solution L. Gas G is supplied into the solution L in the treatment tank 10a from the first bubble outlet 33a of the first bubble outlet pipe 32a. The gas G may be, for example, a gas containing nitrogen. The gas G is discharged from the first bubble outlet 33a into the solution L stored in the treatment tank 10a. Gas G supplied into the solution L in the region where the underside of the lid 30a (the surface facing the processing tank 10a) is lower in the vertical direction (Z direction) moves along the slope of the underside of the lid 30a (the surface facing the processing tank 10a) to the region where it is higher in the vertical direction (Z direction), and is discharged from the gap between the two components.

[0039] In the substrate processing method using the substrate processing apparatus 1a according to this embodiment, gas G is supplied from the first bubble outlet 33a into the solution L stored in the processing tank 10a, thereby replacing oxygen from the atmosphere that has dissolved into the solution L from the liquid surface with gas G, thereby further reducing the amount of oxygen dissolved in the solution L. Furthermore, since the lid 30a is in contact with the liquid surface of the solution L, oxygen from the atmosphere is prevented from dissolving into the solution L from the liquid surface, thereby reducing the amount of oxygen dissolved in the solution L during the etching process. This improves the uniformity of the etching rate within the substrate S and reduces surface oxidation of the substrate S.

[0040] [Substrate processing method 2] A modified example of the substrate processing method using the substrate processing apparatus 1a according to this embodiment will be described below. The substrate processing method according to this modification is the same as the substrate processing method according to the second embodiment except for the timing of supplying the solution L. Explanations of the same things as the second embodiment will be omitted, and only differences from the substrate processing method according to the second embodiment will be described here. Figures 9 and 10 are diagrams schematically showing a substrate processing method according to one modification.

[0041] As shown in FIG. 9, first, the substrate S is placed on the holding member 20a so that it is vertical (the main surface is in the XZ direction). Inside the processing tank 10a, a solution L is stored partway from the solution supply path 12a. Before immersing the substrate S in the processing tank 10a, gas G may be supplied to the liquid surface of the solution L from the first bubble discharge port 33a to remove dissolved oxygen in advance. It is desirable to discharge the gas G for 5 minutes or more before processing. The holding member 20a holding the substrate S is immersed in the solution L stored in the processing tank 10a.

[0042] As shown in FIG. 10, the lid 30a is closed so that the underside of the lid 30a (the surface facing the treatment tank 10a) is inserted into the treatment tank 10a. The two parts of the lid 30a cannot be closed at the same time, so they are opened and closed one by one. Because the solution L is only partially stored inside the treatment tank 10a, even when the lid 30a is closed, the underside of the lid 30a (the surface facing the treatment tank 10a) does not come into contact with the solution L. After the lid 30a is closed, the solution L is stored inside the treatment tank 10a from the solution supply channel 12a up to the upper opening 11a. The underside of the lid 30a (the surface facing the treatment tank 10a) is positioned below the upper opening 11a of the treatment tank 10a, so it comes into contact with the solution L.

[0043] The substrate processing method using the substrate processing apparatus 1a according to this modified example can prevent the solution L from splashing out of the processing tank 10a by closing the lid 30a and then storing the solution L inside the processing tank 10a up to the upper end opening 11a.

[0044] <Third embodiment> The configuration of the substrate processing apparatus according to this embodiment is the same as that of the substrate processing apparatus according to the second embodiment, except that the processing tank further includes a second bubble discharge pipe. Explanations of the same parts as those in the second embodiment will be omitted, and only the parts that differ from the configuration of the substrate processing apparatus according to the second embodiment will be described here.

[0045] [Configuration of substrate processing equipment] 11 is a diagram schematically illustrating the overall configuration of a substrate processing apparatus according to one embodiment. As shown in FIG. 11, the substrate processing apparatus 1b includes a processing bath 10b, a holding member 20b, and a lid 30b.

[0046] A second bubble discharge pipe 13b is provided at the bottom of the processing tank 10b. The second bubble discharge pipe 13b supplies gas G to the solution L stored in the processing tank 10b. The second bubble discharge pipe 13b is equipped with a second bubble discharge port 14b that supplies gas G to the processing tank 10b. The second bubble discharge port 14b is disposed below the holding member 20b that holds the substrate S. The gas G is discharged from the second bubble discharge port 14b into the solution L stored in the processing tank 10b. The second bubble discharge port 14b is preferably disposed below the holding member 20b that holds the substrate S. The second bubble discharge port 14b and the solution discharge port may be disposed at the same height, or the second bubble discharge port 14b may be disposed above the solution discharge port. The number, size, and arrangement of the second bubble discharge ports 14b are not particularly limited as long as the gas G can be uniformly supplied to the solution L.

[0047] The gas G supplied from the second bubble discharge pipe 13b may be, for example, a gas containing nitrogen. However, this is not limited thereto, and the gas G may be any inert gas. Each second bubble discharge port 14b may supply gas G to the processing tank 10b at approximately the same flow rate. However, this is not limited thereto, and each second bubble discharge port 14b may supply gas G to the processing tank 10b at different flow rates depending on its position relative to the substrate S.

[0048] With the above configuration, the bubbles (gas G) supplied by the second bubble discharge pipe 13b can pass between the substrates S from the bottom of the processing tank 10b and form a flow of the solution L.

[0049] In the substrate processing apparatus 1b according to this embodiment, bubbles (gas G) supplied by the second bubble discharge pipe 13b pass from the bottom of the processing tank 10b between the substrates S and form a flow of the solution L, thereby efficiently replacing atmospheric oxygen dissolved in the solution L from the liquid surface with gas G, and further reducing the amount of dissolved oxygen in the solution L. This improves the uniformity of the etching rate within the substrates S and reduces surface oxidation of the substrates S.

[0050] [Substrate processing method] A substrate processing method using the substrate processing apparatus 1b according to this embodiment will be described below. The substrate processing method according to this embodiment is the same as the substrate processing method according to the second embodiment, except that gas G is supplied from the second bubble discharge pipe. Explanations of the same things as in the second embodiment will be omitted, and only differences from the substrate processing method according to the second embodiment will be described here. Figure 12 is a diagram schematically showing a substrate processing method according to one embodiment.

[0051] As shown in FIG. 12, gas G is supplied into the solution L from a first bubble outlet 33b disposed in the lid 30b, and gas G is supplied into the solution L from a second bubble outlet 14b disposed at the bottom of the processing tank 10b. The gas G is, for example, nitrogen. The gas G is discharged from the first bubble outlet 33b and the second bubble outlet 14b into the solution L stored in the processing tank 10b. The gas G supplied from the second bubble outlet 14b at the bottom of the processing tank 10b passes between the substrates S and forms a flow of the solution L. Before immersing the substrates S in the processing tank 10b, gas G may be supplied to the surface of the solution L from the first bubble outlet 33b and gas G may also be discharged from the second bubble outlet 14b simultaneously to remove dissolved oxygen. It is desirable to discharge gas G for at least five minutes before processing.

[0052] In the substrate processing method using the substrate processing apparatus 1b according to this embodiment, bubbles (gas G) supplied by the second bubble discharge pipe 13b pass from the bottom of the processing tank 10b between the substrates S and form a flow of the solution L, thereby efficiently replacing atmospheric oxygen dissolved in the solution L from the liquid surface with gas G and further suppressing the amount of dissolved oxygen in the solution L. This improves the uniformity of the etching rate within the substrates S and suppresses surface oxidation of the substrates S.

[0053] <Fourth embodiment> The configuration of the substrate processing apparatus according to this embodiment is the same as that of the substrate processing apparatus according to the third embodiment, except that it is provided with a circulation line for the solution L. Explanations of the same things as in the third embodiment will be omitted, and only the parts that differ from the configuration of the substrate processing apparatus according to the third embodiment will be described here.

[0054] [Configuration of substrate processing equipment] Fig. 13 is a diagram schematically illustrating the overall configuration of a substrate processing apparatus according to an embodiment. Fig. 14 is a top view schematically illustrating the structure of a substrate processing apparatus according to an embodiment. As shown in Fig. 13, a substrate processing apparatus 1c includes a processing tank 10c, a holding member 20c, a lid 30c, and a circulation path 40c.

[0055] As shown in Figures 13 and 14, the treatment tank 10c further includes an outer tank 15c. The outer tank 15c completely surrounds the upper opening 11c of the treatment tank 10c. In Figure 14, the shaft 31c is omitted to show the relationship between the upper opening 11c of the treatment tank 10c and the outer tank 15c. The outer tank 15c has an outer tank cover 16c at its top. There is a gap between the outer tank cover 16c and the upper opening 11c of the treatment tank 10c. The outer tank 15c uses this gap to collect the solution L that overflows from the upper opening 11c of the treatment tank 10c.

[0056] A third bubble discharge pipe 17c is provided at the bottom of the outer tank 15c. The third bubble discharge pipe 17c supplies gas G to the solution L stored in the outer tank 15c. The third bubble discharge pipe 17c is equipped with third bubble discharge ports 18c that supply gas G to the outer tank 15c. The gas G is discharged from the third bubble discharge ports 18c into the solution L stored in the outer tank 15c. The number, size, and arrangement of the third bubble discharge ports 18c are not particularly limited as long as the gas G can be supplied uniformly to the solution L.

[0057] The gas G supplied from the third bubble outlets 18c may be, for example, a gas containing nitrogen. However, the present invention is not limited to this, and the gas G may be any inert gas. Each of the third bubble outlets 18c may supply the gas G to the processing tank 10c at approximately the same flow rate. However, the present invention is not limited to this, and each of the third bubble outlets 18c may supply the gas G to the outer tank 15c at different flow rates depending on the arrangement of the third bubble outlets 18c relative to the processing tank 10c.

[0058] The circulation path 40c is connected to the bottom of the outer bath 15c and the bottom of the treatment bath 10c to circulate the solution L. Specifically, the circulation path 40c returns the solution L that has flowed into the outer bath 15c to the treatment bath 10c. During this return process, the solution L passes through the filter cartridge FC1, the filter cartridge FC2, the pump P, the heating unit H, and the filter F in this order.

[0059] The filter cartridges FC1 and FC2 are located upstream of the pump P in the circulation path 40c. The filter cartridges FC1 and FC2 are hollow fiber membranes. The filter cartridge FC1 is connected to a vacuum pump and removes dissolved gases from the solution L in the circulation path 40c. The dissolved gases include, for example, oxygen dissolved in the solution L from the atmosphere. The filter cartridge FC2 adds gas G to the solution L in the circulation path 40c. This gas G may be, for example, nitrogen. However, this is not limited thereto; the gas G may be any inert gas. In FIG. 13, the filter cartridges FC1 and FC2 are arranged in this order, but this may be reversed, i.e., filter cartridge FC2, then filter cartridge FC1. Furthermore, although a single set of filter cartridges FC1 and FC2 is shown, the number of filter cartridges FC1 and FC2 is not particularly limited. Furthermore, although the filter cartridges FC1 and FC2 are combined, only filter cartridge FC1 or only filter cartridge FC2 may be used. In this case, the number of filter cartridges FC1 only or the number of filter cartridges FC2 only is not particularly limited.

[0060] The pump P is provided downstream of the filter cartridges FC1 and FC2 on the circulation path 40c and upstream of the heating unit H on the circulation path 40c. The pump P sucks the solution L from the outer tank 15c, causing the solution L collected in the outer tank 15c to move through the filter cartridges FC1 and FC2 to the heating unit H. The pump P also pressurizes the solution L heated in the heating unit H, causing the solution L to be supplied to the treatment tank 10c.

[0061] The heating unit H is provided in the middle of the circulation path 40c. The heating unit H heats the solution L. The heating unit H is, for example, a line heater that uses a halogen lamp as a heat source. The solution L heated by the heating unit H is supplied into the treatment tank 10c through the filter F.

[0062] The filter F is provided downstream of the heating unit H on the circulation path 40c. The filter F removes particles contained in the solution L in the circulation path 40c. These particles include, for example, metal or silica dissolved in the solution L by the etching process of the substrate S. The filter F may be provided upstream of the heating unit H on the circulation path 40c.

[0063] In the substrate processing apparatus 1c according to this embodiment, the third bubble discharge pipe 17c supplies bubbles (gas G) from the bottom of the outer tank 15c, thereby replacing atmospheric oxygen dissolved in the solution L recovered from the processing tank 10c with gas G, thereby reducing the amount of dissolved oxygen in the recirculating solution L. The outer tank 15c is provided with an outer tank cover 16c on its top, thereby reducing atmospheric oxygen dissolution from the surface of the solution L. Furthermore, the filter cartridges FC1 and FC2 in the circulation path 40c perform degassing and suction, thereby efficiently replacing atmospheric oxygen dissolved in the recirculating solution L with gas G, thereby further reducing the amount of dissolved oxygen in the solution L. This improves the uniformity of the etching rate within the substrate S and reduces surface oxidation of the substrate S.

[0064] Fifth Embodiment The configuration of the substrate processing apparatus according to this embodiment is the same as that of the substrate processing apparatus according to the fourth embodiment, except that it includes chemical solution preparation tanks 41d, 42d, 43d, 44d, and 45d instead of filter cartridges FC1 and FC2. Explanations of the same things as in the fourth embodiment will be omitted, and only differences from the configuration of the substrate processing apparatus according to the fourth embodiment will be described here.

[0065] [Configuration of substrate processing equipment] 15 is a diagram schematically illustrating the overall configuration of a substrate processing apparatus according to one embodiment. As shown in FIG. 15, the substrate processing apparatus 1d includes a processing bath 10d, a holding member 20d, a lid 30d, and a circulation path 40d.

[0066] Circulation path 40d is connected to the bottom of outer bath 15d and the bottom of treatment bath 10d to circulate solution L. Specifically, circulation path 40d returns solution L that has flowed into outer bath 15d to treatment bath 10d. During this return process, solution L passes through chemical solution preparation baths 41d, 42d, 43d, 44d, 45d, pump P, heating unit H, and filter F in this order.

[0067] Chemical solution preparation tanks 41d, 42d, 43d, 44d, and 45d are located upstream of pump P on circulation path 40d. Chemical solution preparation tanks 41d, 42d, 43d, 44d, and 45d have smaller capacities than treatment tank 10d, and gas G is added in each chemical solution preparation tank. Solution L to be returned to circulation path 40d is first introduced sequentially from chemical solution preparation tank 41d. At the same time that solution L begins to be introduced into chemical solution preparation tank 45d, solution L is simultaneously supplied from chemical solution preparation tank 41d to circulation path 40d. Gas G is added to each of chemical solution preparation tanks 41d, 42d, 43d, 44d, and 45d for at least 10 minutes. This gas G may be, for example, nitrogen. However, this is not limited thereto; gas G may be any inert gas. While five chemical solution preparation tanks are shown in FIG. 13, the number of chemical solution preparation tanks is not particularly limited.

[0068] In the substrate processing apparatus 1d according to this embodiment, by adding gas G in the chemical solution preparation tanks 41d, 42d, 43d, 44d, and 45d of the circulation path 40d, oxygen from the atmosphere dissolved in the circulating solution L can be efficiently replaced with gas G, and the amount of dissolved oxygen in the solution L can be further reduced. As a result, the uniformity of the etching rate within the substrate S can be improved, and surface oxidation of the substrate S can be reduced.

[0069] <Modification> A modified example of the substrate processing method using the substrate processing apparatus 1d according to this embodiment will be described below. The substrate processing method according to this modification is the same as the substrate processing method according to the fifth embodiment, except that gas G is added before the substrate S is placed on the substrate. Explanations of the same aspects as the fifth embodiment will be omitted, and only differences from the substrate processing method according to the fifth embodiment will be described here. Figure 16 is a diagram schematically illustrating a substrate processing method according to one modification.

[0070] 16, first, gas G is added to the processing tank 10d and the outer tank 15d before the substrate S is placed therein. Gas G is added to the processing tank 10d and the outer tank 15d for at least 5 minutes before the substrate S is immersed, and always while the substrate S is immersed. This gas G may be, for example, nitrogen. However, the gas G is not limited to this and may be any inert gas.

[0071] In the substrate processing method using the substrate processing apparatus 1d according to this modification, the amount of dissolved oxygen in the solution L can be further reduced by adding the gas G to the solution L before the substrate S is placed thereon.

[0072] The substrate processing apparatuses and substrate processing methods according to the first to fifth embodiments described above can be combined as appropriate. For example, the configuration of the substrate processing apparatus according to the third to fifth embodiments may be applied to the configuration of the substrate processing apparatus according to the first embodiment.

[0073] The substrate processing methods according to the first to fifth embodiments can be used as part of a method for manufacturing a semiconductor device, such as, but not limited to, a 3D NAND flash memory.

[0074] Although the present invention has been described above with reference to the drawings, the present invention is not limited to the above-described embodiments and can be modified as appropriate without departing from the spirit of the present invention. For example, a substrate processing apparatus according to the present embodiment can be modified by a person skilled in the art by adding, deleting, or modifying components as appropriate, and the modifications will still fall within the scope of the present invention as long as they incorporate the gist of the present invention. Furthermore, the above-described embodiments and modifications can be combined as appropriate as long as they are not mutually inconsistent, and technical features common to the embodiments are included in the modifications even if not explicitly stated.

[0075] Even if there are other effects and advantages different from those brought about by the aspects of each of the above-mentioned embodiments, those that are clear from the description in this specification or that can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0076] S substrate, L solution, G gas, 1 substrate processing apparatus, 10 processing tank, 11 upper end opening, 12 solution supply path, 13b second bubble discharge pipe, 14b second bubble discharge port, 15c outer tank, 16c outer tank cover, 17c third bubble discharge pipe, 20 holding member, 30 lid, 31 shaft, 32 first bubble discharge pipe, 33 first bubble discharge port, 40c circulation path, 41d, 42d, 43d, 44d, 45d chemical solution preparation tank

Claims

1. a treatment tank that stores a chemical and is capable of immersing a substrate in the chemical to perform treatment; a holding member for holding the substrate; a lid disposed on the treatment tank and having a first bubble discharge pipe disposed therein for discharging an inert gas; A substrate processing apparatus, wherein a surface of the lid facing the processing tank is in contact with the chemical, and the first air bubble discharge pipe discharges the gas into the chemical while the lid and the chemical are in contact with each other.

2. The substrate processing apparatus according to claim 1 , wherein the surface is disposed at an angle relative to the horizontal direction.

3. A substrate processing apparatus as described in claim 2, wherein the first bubble discharge pipes are arranged more in areas where the surface is vertically low than in areas where the surface is vertically high.

4. The substrate processing apparatus according to claim 1 , further comprising a second bubble discharge pipe disposed below the holding member and configured to discharge an inert gas into the chemical.

5. The substrate processing apparatus of claim 1 , wherein the gas includes nitrogen.

6. a substrate processing apparatus including a processing tank capable of storing a chemical, a holding member for holding a substrate, and a lid disposed on the processing tank and having a first bubble discharge pipe provided therein; Immersing the substrate in the agent; A substrate processing method in which the surface of the lid facing the processing tank is brought into contact with the chemical, and an inert gas is ejected into the chemical from the first bubble ejection pipe while the lid and the chemical are in contact.

7. a substrate processing apparatus including a processing tank capable of storing a chemical, a holding member for holding a semiconductor substrate, and a lid disposed on the processing tank and having a first bubble discharge pipe; Immersing the semiconductor substrate in the agent; A method for manufacturing a semiconductor device, wherein the surface of the lid facing the processing tank is brought into contact with the chemical, and an inert gas is ejected into the chemical from the first bubble ejection pipe while the lid and the chemical are in contact.

8. the semiconductor substrate has metal wiring; The agent is a solution L of an inorganic acid including sulfuric acid, nitric acid, hydrochloric acid, or hydrofluoric acid, or an organic acid including acetic acid or citric acid; The method for manufacturing a semiconductor device according to claim 7 , wherein the gas contains nitrogen.

9. the semiconductor substrate comprises silicon; the agent is a solution containing hydrogen peroxide; The method for manufacturing a semiconductor device according to claim 7 , wherein the gas contains nitrogen.

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