Substrate processing method

Abstract

A substrate processing method for forming a positive pattern mask is provided. The substrate processing method comprises: a step of preparing a substrate including a photoresist film including a metal oxide containing a first metal element; a step of performing an exposure treatment on the substrate to form an exposed portion and an unexposed portion on the photoresist film; a step of supplying a metal-containing gas containing a second metal element different from the first metal element to the substrate to form a metal oxide film containing the second metal element on the exposed surface of the unexposed portion; and a step of removing the exposed portion of the photoresist film using the metal oxide film as a mask.

Description

Technology Field

[0001] The present disclosure relates to a substrate processing method. Background Technology

[0002] Patent Document 1 discloses a method for manufacturing a semiconductor device characterized by including a process of depositing an organic insulating film on a semiconductor substrate, a process of selectively forming a silylated layer on the organic insulating film, and a process of etching the organic insulating film using the silylated layer as a mask to form a recess in the organic insulating film that becomes a connection hole or a wiring groove. Prior art literature

[0003] Japanese Patent Publication No. 2001-168192 The problem to be solved

[0004] In one aspect, the present disclosure provides a substrate processing method for forming a mask of a positive pattern. means of solving the problem

[0005] To solve the above problem, a substrate processing method is provided, comprising: a process of preparing a substrate including a photoresist film including a metal oxide including a first metal element; a process of performing an exposure treatment on the substrate to form an exposed portion and an unexposed portion on the photoresist film; a process of supplying a metal-containing gas including a second metal element different from the first metal element to the substrate to form a metal oxide film including the second metal element on the exposed surface of the unexposed portion; and a process of removing the exposed portion of the photoresist film using the metal oxide film as a mask. Effects of the invention

[0006] According to one aspect, a substrate processing method for forming a positive pattern mask can be provided. Brief explanation of the drawing

[0007] FIG. 1 is a flowchart illustrating an example of a substrate processing method according to a first embodiment. Figure 2 is an example of a schematic diagram of a substrate in each process. Figure 3a is an example of a schematic diagram of a substrate in each process. Figure 3b is an example of a schematic diagram of a substrate in each process. Figure 4a is an example of a schematic diagram of a substrate in each process. Figure 4b is an example of a schematic diagram of a substrate in each process. Figure 5a is an example of a schematic diagram of a substrate in each process. Figure 5b is an example of a schematic diagram of a substrate in each process. Figure 6a is an example of a schematic diagram of a substrate in each process. Figure 6b is an example of a schematic diagram of a substrate in each process. Figure 7 is a schematic diagram showing an example of a substrate processing device. Figure 8 is a flowchart showing an example of film formation processing of a substrate processing device. FIG. 9 is a flowchart illustrating an example of a substrate processing method according to a second embodiment. Figure 10a is an example of a schematic diagram of a substrate in each process. Figure 10b is an example of a schematic diagram of a substrate in each process. Figure 11a is an example of a schematic diagram of a substrate in each process. Figure 11b is an example of a schematic diagram of a substrate in each process. Figure 12a is an example of a schematic diagram of a substrate in each process. Figure 12b is an example of a schematic diagram of a substrate in each process. Figure 13a is an example of a schematic diagram of a substrate in each process. Figure 13b is an example of a schematic diagram of a substrate in each process. Figure 14a is an example of a schematic diagram of a substrate in each process. Figure 14b is an example of a schematic diagram of a substrate in each process. Specific details for implementing the invention

[0008] Hereinafter, embodiments for implementing the present disclosure will be described with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant descriptions may be omitted.

[0009] <First Embodiment>

[0010] An example of a substrate processing method according to the first embodiment will be described using FIGS. 1 to 6b. FIG. 1 is a flowchart illustrating an example of a substrate processing method according to the first embodiment. FIGS. 2 to 6b are examples of schematic diagrams of a substrate in each process. FIG. 2 is a schematic cross-sectional diagram of a substrate. FIG. 3a and FIG. 3b, FIG. 3b is a schematic cross-sectional diagram of a substrate viewed from above. FIG. 3a is a schematic cross-sectional diagram cut at AA in FIG. 3b. Likewise, FIG. 4a and FIG. 4b, FIG. 4b is a schematic cross-sectional diagram of a substrate viewed from above. FIG. 4a is a schematic cross-sectional diagram cut at AA in FIG. 4b. FIG. 5a and FIG. 5b, FIG. 5b is a schematic cross-sectional diagram of a substrate viewed from above. FIG. 5a is a schematic cross-sectional diagram cut at AA in FIG. 5b. In FIGS. 6a and 6b, FIG. 6b is a schematic view of a substrate viewed from above. FIG. 6a is a schematic cross-sectional view taken at AA in FIG. 6b. Additionally, FIGS. 3b, 4b, 5b, and 6b are views from above, and each component is illustrated with hatching similar to that of the cross-sections in FIGS. 3a, 4a, 5a, and 6a.

[0011] In step S101, a substrate is prepared. Here, the prepared substrate includes a lower film (310) (see FIG. 2). The lower film (310) is a film placed below a photoresist film (320) (see FIG. 2) described later. Additionally, the lower film (310) is a film in which the opening pattern of the mask (320A) (see FIG. 6a and FIG. 6b), which has a pattern of openings (325) formed thereon, is transferred by an etching process using the mask (320A) as a mask. The lower film (310) may be, for example, a silicon-containing film (e.g., SOG (Spin On Glass) film, etc.), a carbon-containing film (e.g., SOC (Spin On Carbon) film, etc.). Additionally, the lower film (310) may be a laminated film in which a plurality of films, such as silicon-containing films and carbon-containing films, are laminated. Additionally, the bottom film (310) as a laminated film may include a film such as a Bottom Anti-Reflective Coating (BARC). The bottom film (310) may be, for example, a film used as a hard mask.

[0012] In step S102, a process of forming a photoresist film (320) on a substrate is performed. FIG. 2 is an example of a schematic diagram of a substrate after the formation of the photoresist film (320).

[0013] Here, a photoresist film (320) is formed on the substrate (310). The photoresist film (320) is a film comprising a metal oxide containing a first metal element. Additionally, the photoresist film (320) may be a metal oxide resist containing the first metal element, or a resin resist (Chemically Amplified Resists (CAR)) using a metal oxide containing the first metal element as a sensitizer, but is not limited thereto. Here, the first metal element includes one or more of Sn, W, Te, Zn, Zr, Sb, In, etc. The metal oxide is, for example, SnO x (x is an arbitrary number), WOx (x is an arbitrary number), TeO x (x is an arbitrary number), ZnO x (x is an arbitrary number), ZrO x (x is an arbitrary number), SbO x (x is an arbitrary number), InO x (x is any number) etc. In addition, the photoresist film (320) changes the valence or oxidation number of the first metal element by exposure to EUV (Extreme Ultraviolet) during the exposure treatment (see S103) described later. In addition, the photoresist film (320) is a negative type photoresist film.

[0014] In step S103, photolithography is performed on the substrate. FIGS. 3a and FIGS. 3b are examples of schematic diagrams of the substrate after photolithography.

[0015] Here, under a nitrogen atmosphere, EUV is irradiated onto a photoresist film (320) of a substrate through a photomask (not shown) having a predetermined pattern. As a result, as shown in FIGS. 3a and 3b, an exposed portion (321) irradiated with EUV and an unexposed portion (322) irradiated with EUV are formed on the photoresist film (320). Additionally, as shown in FIGS. 10a and 10b described later, the photoresist film (320) may have a reaction layer (321a) (fully exposed portion) formed on the central side of the exposed portion (321) and an unreacted material-containing layer (321b) (intermediately exposed portion) formed on the outer side of the exposed portion (321). The reaction layer (321a) is a region in which the valence or oxidation number of the first metal element is changed by the EUV after sufficient exposure. The unreacted material-containing layer (321b) is a region where, due to insufficient EUV exposure, a first metal element remains in some parts without a change in valence or oxidation number. Additionally, in the unexposed portion (322), a first metal element remains where, due to no EUV exposure, a first metal element remains without a change in valence or oxidation number.

[0016] In step S104, a process of selectively depositing a metal oxide film (330) is performed on the upper surface (exposed surface) of the unexposed portion (322) of the photoresist film (320). FIGS. 4a and 4b are examples of schematic diagrams of a substrate after the selective deposition process of the metal oxide film (330). Additionally, the process of selectively depositing the metal oxide film (330) will be described later using FIGS. 7 and 8. By doing so, a metal oxide film (330) is deposited on the upper surface of the unexposed portion (322). Furthermore, if the exposure portion (321) includes a reaction layer (321a) (completely exposed portion) and an unreacted material containing layer (321b) (intermediately exposed portion), a metal oxide film (330) is deposited on the upper surface of the unexposed portion (322) and the unreacted material containing layer (321b) (intermediately exposed portion).

[0017] In step S105, a resist etching process is performed. FIGS. 5a and FIGS. 5b are examples of schematic diagrams of a substrate after the resist etching process.

[0018] Here, an etching treatment is performed on a photoresist film (320) using a metal oxide film (330) as a mask. By doing so, the exposure portion (321) is etched to form a mask (320A) including an opening (325). Additionally, if the exposure portion (321) includes a reaction layer (321a) (completely exposed portion) and an unreacted material containing layer (321b) (intermediately exposed portion), the reaction layer (321a) (completely exposed portion) is etched to form a mask (320A) including an opening (325).

[0019] In step S106, a metal oxide film etching treatment is performed. FIGS. 6a and 6b are examples of schematic diagrams of a substrate after the metal oxide film etching treatment. Here, the metal oxide film (330) is removed by the etching treatment. Additionally, if the metal oxide film (330) does not affect other processes, the treatment in step S106 may be omitted.

[0020] As described above, according to the substrate processing method shown in FIG. 2, a mask (320A) can be formed on the substrate in which the exposed portion in the exposure processing (S103) is an opening (325). That is, a positive pattern mask (320A) can be formed on the substrate.

[0021] Next, the processing shown in step S104 will be explained using FIGS. 7 and 8.

[0022] First, an example of a substrate processing apparatus that performs the processing shown in step S104 on a substrate (W) will be described using FIG. 7. FIG. 7 is a schematic diagram showing an example of a substrate processing apparatus.

[0023] The substrate processing device includes a processing container (1), a loading platform (2), a shower head (3), an exhaust unit (4), a gas supply unit (5), and a control unit (6).

[0024] The processing vessel (1) is constructed of a metal such as aluminum and has a roughly cylindrical shape. The processing vessel (1) accommodates a substrate (W). An inlet / outlet port (11) for bringing in or taking out the substrate (W) is formed on the side wall of the processing vessel (1). The inlet / outlet port (11) is opened and closed by a gate valve (12). An annular exhaust duct (13) with a rectangular cross-section is provided on the main body of the processing vessel (1). A slit (13a) is formed along the inner surface of the exhaust duct (13). An exhaust port (13b) is formed on the outer wall of the exhaust duct (13). A ceiling wall (14) is provided on the upper surface of the exhaust duct (13) to block the upper opening of the processing vessel (1). The space between the exhaust duct (13) and the ceiling wall (14) is hermetically sealed with a seal ring (15).

[0025] The loading platform (2) supports the substrate (W) horizontally within the processing container (1). The loading platform (2) has a disc shape larger than the substrate (W) and is composed of a ceramic material such as aluminum nitride (AlN) or a metal material such as an aluminum or nickel alloy. A heater (21) for heating the substrate (W) is embedded inside the loading platform (2). The heater (21) is powered by a heater power source (not shown) and generates heat. By controlling the output of the heater (21) based on a temperature signal from a thermocouple (not shown) provided near the upper surface of the loading platform (2), the substrate (W) is controlled to a predetermined temperature. The loading platform (2) is provided with a cover member (22) formed of a ceramic material such as alumina to cover the outer periphery of the upper surface and the side.

[0026] The loading platform (2) is supported by a support member (23). The support member (23) extends downward from the center of the bottom surface of the loading platform (2) through a hole formed in the bottom wall of the processing container (1), and its lower end is connected to a lifting mechanism (24). The loading platform (2) is raised by the lifting mechanism (24) between the processing position indicated by the solid line in FIG. 7 and the conveying position where the substrate (W) can be conveyed, indicated by the dotted line below it. A flange portion (25) is installed on the lower side of the processing container (1) of the support member (23). A bellows (26) is provided between the bottom surface of the processing container (1) and the flange portion (25). The bellows (26) separates the atmosphere inside the processing container (1) from the outside air and extends and retracts according to the lifting operation of the loading platform (2).

[0027] Near the bottom surface of the processing container (1), three wafer support pins (27) (only two are shown) are provided to protrude upward from the lifting plate (27a). The wafer support pins (27) are raised and lowered through the lifting plate (27a) by a lifting mechanism (28) provided at the bottom of the processing container (1). The wafer support pins (27) are inserted through a through hole (2a) provided in the loading platform (2) at the transfer position and are made to protrude and sink with respect to the upper surface of the loading platform (2). By raising and lowering the wafer support pins (27), the transfer of the substrate (W) between the transfer robot (not shown) and the loading platform (2) is performed.

[0028] The shower head (3) supplies the processing gas into the processing vessel (1) in a shower shape. The shower head (3) is formed, for example, by a metal material and is positioned opposite the loading platform (2). The shower head (3) has a diameter approximately equal to that of the loading platform (2). The shower head (3) includes a main body (31) and a shower plate (32). The main body (31) is fixed to the lower surface of the ceiling wall (14). The shower plate (32) is connected below the main body (31). A gas diffusion space (33) is formed between the main body (31) and the shower plate (32). In the gas diffusion space (33), a gas introduction hole (36) is provided to penetrate the center of the ceiling wall (14) and the main body (31). An annular projection (34) protruding downward is formed on the periphery of the shower plate (32). A plurality of gas discharge holes (35) are formed on the inner flat surface of the annular projection (34) in the shower plate (32).

[0029] When the loading platform (2) is in the processing position, a processing space (38) is formed between the loading platform (2) and the shower plate (32), and an annular gap (39) is formed by the upper surface of the cover member (22) and the annular projection (34) being in close proximity.

[0030] The exhaust section (4) exhausts the interior of the processing vessel (1). The exhaust section (4) includes an exhaust pipe (41) and an exhaust mechanism (42). The exhaust pipe (41) is connected to the exhaust port (13b). The exhaust mechanism (42) is connected to the exhaust pipe (41) and includes a vacuum pump, a pressure control valve, etc. The exhaust mechanism (42) exhausts the gas inside the processing vessel (1) through the exhaust duct (13) and the exhaust pipe (41).

[0031] The gas supply unit (5) supplies various gases to the shower head (3). The gas supply unit (5) includes a gas supply source (51). The gas supply source (51) supplies various processing gases to the processing space (38) from the gas discharge hole (35) through the gas introduction hole (36) and the gas diffusion space (33).

[0032] The control unit (6) is, for example, a computer and includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or auxiliary storage device and controls the operation of the substrate processing device. The control unit (6) may be provided inside the substrate processing device or outside of it. If the control unit (6) is provided outside of the substrate processing device, the control unit (6) can control the substrate processing device via a communication network such as a wired or wireless network.

[0033] Next, an example of film deposition processing of a substrate processing device will be explained using FIG. 8. FIG. 8 is a flowchart showing an example of film deposition processing of a substrate processing device.

[0034] In step S201, a substrate is prepared. Here, the substrate being prepared includes an exposed portion (321) and an unexposed portion (322) on a photoresist film (320), as shown in FIG. 3a and FIG. 3b.

[0035] In step S202, a metal-containing gas containing a second metal element different from the first metal element is supplied to the substrate as a precursor gas (film-forming gas). Here, the control unit (6) controls the gas supply unit (5) to supply the metal-containing gas containing the second metal element into the processing vessel (1). The second metal element includes one or more of Al, Ti, Ga, Ru, Hf, Sn, W, Te, Zn, Zr, Sb, In, etc., only when not used as the first metal element. In other words, if any of "Sn, W, Te, Zn, Zr, Sb, In" is selected as the first metal element, the second metal element may be selected from "Al, Ti, Ga, Ru, Hf" and "Sn, W, Te, Zn, Zr, Sb, In," excluding the element selected as the first metal element. As metal-containing gases containing a second metal element, examples include TMA (trimethylaluminum), TDMAT (tetrakis(dimethylamino)titanium), TEGa (triethylgallium), and Ru3CO 12 It includes one or more of the above. In addition, by making the temperature lower than the temperature at which the metal-containing gas forms a film by thermal decomposition, the formation of the metal oxide film (330) on the upper surface of the exposure part (321) is suppressed.

[0036] Meanwhile, on the upper surface of the unexposed portion (322), a first metal element remaining in the unexposed portion (322) that has not changed in terms of valence or oxidation number is used as a catalyst to react with a metal-containing gas containing a second metal element, thereby decomposing the precursor of the metal-containing gas and selectively forming a metal oxide film (metal-containing film) (330) on the upper surface of the unexposed portion (322).

[0037] In step S203, an inert gas is supplied to the substrate. The control unit (6) controls the gas supply unit (5) to supply the inert gas into the processing vessel (1). The inert gas is an inert gas to the photoresist film (320) or the metal-containing gas. The inert gas includes one or more of nitrogen (N2) gas, Ar gas, He gas, etc. Here, the metal-containing gas physically adsorbed on the upper surface of the exposure unit (321) is purged with the inert gas.

[0038] In step S204, the control unit (6) determines whether the processing of steps S202 and S203 has been repeated a predetermined number of times. If it has not been repeated a predetermined number of times (S204 “No”), the processing of the control unit (6) returns to step S202 and is repeated. Here, when the film thickness of the metal oxide film (330) reaches a predetermined film thickness (e.g., about 1 nm), the catalytic effect of the unexposed part (322) is eliminated, and the growth of the metal oxide film (330) is stopped. By doing so, the film thickness of the metal oxide film (330) can be appropriately controlled. Then, if it has been repeated a predetermined number of times (S204 “Yes”), the processing of the control unit (6) is terminated.

[0039] As described above, according to the film formation method shown in FIG. 8, a metal oxide film (330) can be selectively formed on the upper surface of the unexposed portion (322) with respect to the upper surface of the exposed portion (321). Additionally, if the exposed portion (321) includes a reaction layer (321a) (fully exposed portion) and an unreacted material containing layer (321b) (intermediate exposed portion), a metal oxide film (330) can be selectively formed on the upper surface of the unexposed portion (322) and the unreacted material containing layer (321b) (intermediate exposed portion) with respect to the upper surface of the reaction layer (321a) (fully exposed portion).

[0040] Additionally, although it has been described that in step S202, a metal-containing gas containing a second metal element is supplied as a precursor gas (film-forming gas) to form a metal oxide film (330) containing the second metal element on the upper surface of the unexposed portion (322) and the unreacted material-containing layer (321b), this is not limited thereto. Instead of a metal-containing gas as a precursor gas (film-forming gas), a semiconductor gas containing one or more semiconductor raw materials (semiconductor elements) such as Si, B, Ge, and Se may be supplied into the processing vessel (1) to form a semiconductor film (not shown) containing a semiconductor raw material (semiconductor element) different from the first metal element on the upper surface of the unexposed portion (322) and the unreacted material-containing layer (321b). That is, in step S202, either the metal-containing gas containing the second metal element or the semiconductor gas containing the semiconductor raw material may be supplied. Accordingly, the configuration may be such that a semiconductor film (not shown) containing a semiconductor raw material (semiconductor element) is selectively formed on the upper surface of the unexposed portion (322) and the unreacted material containing layer (321b). Furthermore, it is not limited to this, and in step S202, both a metal-containing gas containing a second metal element and a semiconductor gas containing a semiconductor raw material may be supplied.

[0041] <Second Embodiment>

[0042] An example of a substrate processing method according to the second embodiment will be explained using FIGS. 9 to 14b. FIG. 9 is a flowchart illustrating an example of a substrate processing method according to the second embodiment. FIGS. 10a to 14b are examples of schematic diagrams of a substrate in each process. Also, in FIGS. 10a and 10b, FIG. 10b is a schematic diagram of a substrate viewed from above. FIG. 10a is a schematic cross-sectional diagram cut at AA in FIG. 10b. Likewise, in FIGS. 11a and 11b, FIG. 11b is a schematic cross-sectional diagram cut at AA in FIG. 11b. FIG. 11a is a schematic cross-sectional diagram cut at AA in FIG. 11b. In FIGS. 12a and 12b, FIG. 12b is a schematic diagram of a substrate viewed from above. FIG. 12a is a schematic cross-sectional diagram cut at AA in FIG. 12b. In FIG. 13a and FIG. 13b, FIG. 13b is a schematic diagram of the substrate viewed from above. FIG. 13a is a schematic cross-sectional view taken at AA in FIG. 13b. In FIG. 14a and FIG. 14b, FIG. 14b is a schematic diagram of the substrate viewed from above. FIG. 14a is a schematic cross-sectional view taken at AA in FIG. 14b. Additionally, FIG. 10b, 11b, 12b, 13b, and 14b are top-view drawings, but each component is illustrated with hatching similar to that of the cross-sections in FIG. 10a, 11a, 12a, 13a, and 14a.

[0043] In step S301, a substrate is prepared. Here, the prepared substrate includes a lower film (310) (see FIG. 2). The lower film (310) is a film placed below a photoresist film (320) (see FIG. 2) described later. Additionally, the lower film (310) is a film in which the opening pattern of a mask is transferred by an etching process using a metal oxide film (330) (see FIG. 14a, FIG. 14b) having a pattern of openings (335) formed thereon, described later, as a mask. The lower film (310) may be, for example, a silicon-containing film (e.g., SOG (Spin On Glass) film, etc.), a carbon-containing film (e.g., SOC (Spin On Carbon) film, etc.). Additionally, the lower film (310) may be a laminated film in which a plurality of films, such as a silicon-containing film and a carbon-containing film, are laminated. Additionally, the bottom film (310) as a laminated film may include a film such as a Bottom Anti-Reflective Coating (BARC). The bottom film (310) may be, for example, a film used as a hard mask.

[0044] In step S302, a process of forming a photoresist film (320) on a substrate is performed. FIG. 2 is an example of a schematic diagram of a substrate after the formation of the photoresist film (320).

[0045] Here, a photoresist film (320) is formed on the substrate (310). The photoresist film (320) is a film comprising a metal oxide containing a first metal element. Additionally, the photoresist film (320) may be a metal oxide resist containing the first metal element, or a resin resist (Chemically Amplified Resists (CAR)) using a metal oxide containing the first metal element as a sensitizer, but is not limited thereto. Here, the first metal element includes one or more of Sn, W, Te, Zn, Zr, Sb, In, etc. The metal oxide is, for example, SnO x (x is an arbitrary number), WOx (x is an arbitrary number), TeO x (x is an arbitrary number), ZnO x (x is an arbitrary number), ZrO x (x is an arbitrary number), SbO x (x is an arbitrary number), InO x (x is any number) etc. In addition, the photoresist film (320) changes the valence or oxidation number of the first metal element by exposure to EUV (Extreme Ultraviolet) during the exposure treatment (see S103) described later. In addition, the photoresist film (320) is a negative type photoresist film.

[0046] In step S303, photolithography is performed on the substrate. FIGS. 10a and FIGS. 10b are examples of schematic diagrams of the substrate after photolithography.

[0047] Here, under a nitrogen atmosphere, EUV is irradiated onto a photoresist film (320) of a substrate through a photomask (not shown) having a predetermined pattern. As a result, as shown in FIG. 10a and FIG. 10b, an exposed portion (321) irradiated with EUV and an unexposed portion (322) irradiated with EUV are formed on the photoresist film (320). Here, as shown in FIG. 10a and FIG. 10b, the photoresist film (320) has a reaction layer (321a) (fully exposed portion) formed on the central side of the exposed portion (321) and an unreacted material-containing layer (321b) (intermediately exposed portion) formed on the outer side of the exposed portion (321). The reaction layer (321a) is a region in which the valence or oxidation number of a first metal element is changed by the EUV after sufficient exposure. The unreacted material-containing layer (321b) is a region where, due to insufficient EUV exposure, a first metal element remains in some parts without a change in valence or oxidation number. Additionally, in the unexposed portion (322), a first metal element remains where, due to no EUV exposure, a first metal element remains without a change in valence or oxidation number.

[0048] In step S304, a development process is performed on the substrate. FIGS. 11a and FIGS. 11b are examples of schematic diagrams of the substrate after the development process.

[0049] Here, by a developing process, a portion of the unexposed portion (322) and the unreacted material-containing layer (322b) of the photoresist film (320) is selectively removed. The developing process may use at least one of a wet process and a dry process. As a result, as shown in FIG. 11a and FIG. 11b, the photoresist film (320) (see FIG. 2) becomes a photoresist film (320B) having a pattern of openings (325). Additionally, the sidewalls of the openings (325) of the photoresist film (320B) are formed from the remainder of the unreacted material-containing layer (322b).

[0050] In step S305, a process is performed to selectively deposit a metal oxide film (330) from the sidewall of the opening (325) of the photoresist film (320B).

[0051] First, a process is performed to selectively deposit a metal oxide film (330) on the sidewall of the opening (325) of the photoresist film (320B). FIGS. 12a and 12b are examples of schematic diagrams of a substrate after the selective deposition of the metal oxide film (330). Here, by the process shown in FIG. 8, a metal oxide film (330) can be selectively formed on the exposed surface (upper surface) of the unreacted material containing layer (321b) (intermediate exposure part) (sidewall of the opening (325)) with respect to the exposed surface (upper surface) of the reaction layer (321a) (complete exposure part).

[0052] Next, a process is performed to grow a metal oxide film (330) formed on the sidewall of the opening (325) of the photoresist film (320B). FIGS. 13a and 13b are examples of schematic diagrams of a substrate after the growth of the metal oxide film (330). Here, by alternately supplying a metal-containing gas and a reaction gas (oxidizing gas) to the substrate, the metal oxide film (330) is grown by the Atomic Layer Deposition (ALD) method, and the metal oxide film (330) is embedded in the opening (325) of the photoresist film (320B). Additionally, starting from the metal oxide film (330) formed on the sidewall of the opening (325) in step S305, the metal oxide film (330) may be selectively grown in a lateral direction. Additionally, the method of forming a metal oxide film (330) in the opening (325) of the photoresist film (320B) is not limited to this, and, for example, a configuration in which a film is formed from the bottom of the opening (325) using a fluid film may also be used.

[0053] Additionally, the metal-containing gas may be the same gas supplied in Step S202. Furthermore, the metal included in the metal-containing gas may be any of B, Al, Si, Ti, V, Mn, Fe, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Pd, In, Sb, Te, Hf, Ta, W, Pt, and Bi. Additionally, the oxidizing gas may be any of water vapor, oxygen, or ozone.

[0054] In step S306, a resist etching process is performed. FIG. 14a and FIG. 14b are examples of schematic diagrams of a substrate after the resist etching process.

[0055] Here, the photoresist film (320B) is removed by an etching process. By doing so, a metal oxide film (330) including an opening (335) is formed. The etching gas may include H2, HF, HCl, HBr, HI, F2, Cl2, Br2, I2, BCl3, CH4, C x -Hy, Cx -Cly, C x -Bry, organic acids (carboxylic acid gases, etc.) halosilanes (Si-Cl x , Si-H x It may be any of -Cly) (where x and y are arbitrary numbers).

[0056] As described above, according to the substrate processing method shown in FIG. 9, a metal oxide film (330) having an opening (335) in the portion exposed in the exposure process (S303) can be formed on a substrate using a mask. That is, a positive pattern mask (a metal oxide film (330) including an opening (335)) can be formed on a substrate.

[0057] Additionally, although the substrate processing apparatus shown in FIG. 7 has been described as an apparatus that performs selective film deposition (S104, S305), it is not limited thereto. In addition to the selective film deposition (S104, S305), the apparatus may be configured to perform one or more of the development process (S304) and the etching process (S105, S106, S306) in addition to the substrate processing apparatus shown in FIG. 7.

[0058] In addition, the apparatus for performing selective film deposition (S104, S305), the apparatus for performing development (S304), and the apparatus for performing etching (S105, S106, S306) may each be composed of separate apparatuses, and the substrate processing apparatus may be one in which these apparatuses are connected to the same transport apparatus.

[0059] Although a substrate processing method according to the present embodiment has been described above, the present disclosure is not limited to the above embodiment, and various modifications and improvements are possible within the scope of the gist of the present disclosure as described in the patent claims.

[0060] In addition, the present invention claims priority based on Japanese patent application No. 2024-002841 filed on January 11, 2024, and incorporates the entire contents of said Japanese patent application by reference herein. Explanation of the symbols

[0061] 310: Lower layer 320, 320B: Photoresist layer 320A: Mask 321: Exposure section 321a: Reaction layer 321b: Unreacted material-containing layer 322: Mino Miner 325: Frog 330: Metal oxide film 335: Aperture

Claims

Claim 1 A substrate processing method comprising: a process of preparing a substrate comprising a photoresist film comprising a metal oxide containing a first metal element; a process of performing an exposure treatment on the substrate to form an exposed portion and an unexposed portion on the photoresist film; a process of supplying a metal-containing gas containing a second metal element different from the first metal element to the substrate to form a metal oxide film containing the second metal element on the exposed surface of the unexposed portion; and a process of removing the exposed portion of the photoresist film using the metal oxide film as a mask. Claim 2 A substrate treatment method according to claim 1, wherein the exposure treatment is performed by exposing to extreme ultraviolet light to form the exposed portion and the unexposed portion on the photoresist film, and the exposed portion comprises a reaction layer which is a region in which the valence or oxidation number of the first metal element is changed by the extreme ultraviolet light, and an unreacted material containing layer which is a region in which the first metal element that has not changed the valence or oxidation number remains. Claim 3 In paragraph 2, the process of forming the metal oxide film is a substrate treatment method in which the first metal element, whose valence or oxidation state of the unexposed portion and the unreacted material-containing layer has not changed, is used as a catalyst to form the metal oxide film containing the second metal element on the exposed surface of the unexposed portion and the unreacted material-containing layer. Claim 4 A substrate processing method comprising: a process of preparing a substrate comprising a photoresist film comprising a metal oxide containing a first metal element; a process of performing exposure treatment and development treatment on the substrate to form a pattern of openings in the photoresist film; a process of supplying a metal-containing gas containing a second metal element different from the first metal element to the substrate to form a metal oxide film containing the second metal element from the sidewall of the openings in the photoresist film; and a process of removing the photoresist film. Claim 5 A substrate treatment method according to claim 4, wherein the exposure treatment is performed by exposing to extreme ultraviolet light to form an exposed portion and an unexposed portion on the photoresist film, and the exposed portion comprises a reaction layer which is a region in which the valence or oxidation number of the first metal element is changed by the extreme ultraviolet light, and an unreacted material containing layer which is a region in which the first metal element that has not changed in valence or oxidation number remains. Claim 6 In paragraph 5, the above-mentioned development treatment is a substrate treatment method that removes a portion of the above-mentioned unexposed portion and the above-mentioned unreacted material-containing layer. Claim 7 In claim 6, the process of forming the metal oxide film is a substrate treatment method in which the first metal element, whose valence or oxidation state of the unreacted material-containing layer has not changed, is used as a catalyst to form the metal oxide film containing the second metal element on the exposed surface of the unreacted material-containing layer. Claim 8 A substrate treatment method according to claim 3 or 7, further comprising a process of supplying an inert gas to the substrate after the process of forming the metal oxide film. Claim 9 In claim 7, the process of forming the metal oxide film comprises: a process of supplying a metal-containing gas containing the second metal element to form the metal oxide film containing the second metal element on the exposed surface of the unreacted material-containing layer; and a substrate treatment method of alternately supplying the metal-containing gas containing the second metal element and the oxide gas to grow the metal oxide film. Claim 10 A substrate processing method according to claim 1 or 4, wherein the first metal element comprises any one of Sn, W, Te, Zn, Zr, Sb, and In. Claim 11 A substrate processing method according to claim 1 or 4, wherein the second metal element comprises any one of Al, Ti, Ga, Ru, Hf, and only when not used as the first metal element, Sn, W, Te, Zn, Zr, Sb, and In. Claim 12 A substrate processing method according to claim 1, wherein, instead of a process of forming a metal oxide film containing the second metal element, a semiconductor gas containing a semiconductor raw material is supplied to the substrate to form a semiconductor film containing the semiconductor raw material different from the first metal element on the sidewall of the photoresist film. Claim 13 In claim 12, the above semiconductor raw material comprises any one of Si, B, Ge, and Se, in a substrate processing method.

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