Substrate processing method

Abstract

Provided is a substrate processing method for forming a resist film which is a thin film, and from which a light-exposed part can be selectively removed.　This substrate processing method comprises: a step for forming a multilayer structure film in which a metal-containing layer and a halogen-containing layer are stacked on a substrate; a step for irradiating the multilayer structure film with extreme ultraviolet light in a predetermined pattern, thereby forming a light-exposed part, which has been irradiated with the extreme ultraviolet light, and an unexposed part, which has not been irradiated with the extreme ultraviolet light, in the multilayer structure film; and a step for selectively removing the light-exposed part of the multilayer structure film.

Description

Substrate processing method

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

[0002] Patent Document 1 discloses a pattern formation method including: forming a photosensitive hard mask made of a transition metal oxide film on the surface of a substrate; exposing the photosensitive hard mask to EUV light in a desired pattern; causing a state change in an exposed region by heat generated during exposure; and selectively removing either the region in which the state change has occurred or the region in which the state change has not occurred.

[0003] JP 2023-12048 A

[0004] In one aspect, the present disclosure provides a substrate processing method for forming a thin resist film that is selectively removable in exposed areas.

[0005] In order to solve the above problem, according to one aspect, there is provided a substrate processing method comprising the steps of: forming a laminated structure film on a substrate, the laminated structure film having a metal-containing layer and a halogen-containing layer stacked thereon; irradiating the laminated structure film with extreme ultraviolet rays in a predetermined pattern to form exposed portions in the laminated structure film that have been irradiated with the extreme ultraviolet rays and unexposed portions in the laminated structure film that have not been irradiated with the extreme ultraviolet rays; and selectively removing the exposed portions of the laminated structure film.

[0006] According to one aspect, the present disclosure can provide a substrate processing method for forming a thin resist film that is selectively removable in exposed areas.

[0007] FIG. 1 is a schematic cross-sectional view showing an example of a substrate processing apparatus according to the present embodiment; FIG. 2 is a flowchart showing an example of a substrate processing method according to the present embodiment; FIG. 3 is a schematic cross-sectional view of a substrate on which a resist film having an opening pattern has been formed by the substrate processing method according to the present embodiment; FIG. 4 is a schematic cross-sectional view of a substrate on which a resist film having an opening pattern has been formed by the substrate processing method according to the present embodiment; FIG. 5 is a schematic cross-sectional view of a substrate on which a resist film having an opening pattern has been formed by the substrate processing method according to the present embodiment; FIG. 6 is a diagram showing a structure of a laminated resist film formed by the substrate processing apparatus according to the present embodiment; FIG. 7 is a diagram showing a structure of a resist film in an exposed portion in each process; FIG. 8 is a diagram showing a structure of a resist film in an unexposed portion in each process.

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] <Substrate Processing Apparatus> An example of a substrate processing apparatus 1 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic cross-sectional view showing an example of the substrate processing apparatus 1 according to this embodiment. The substrate processing apparatus 1 is a film formation apparatus that forms a laminated resist film (laminated structure film) 230 (see Fig. 3A described later) on a substrate W such as a semiconductor wafer by a plasma-based chemical vapor deposition (CVD) method.

[0010] The substrate processing apparatus 1 includes a substantially cylindrical airtight processing vessel 2. An exhaust chamber 21 is provided in the center of the bottom wall of the processing vessel 2.

[0011] The exhaust chamber 21 has, for example, a substantially cylindrical shape that protrudes downward. An exhaust flow path 22 is connected to the exhaust chamber 21, for example, at a side surface of the exhaust chamber 21.

[0012] An exhaust unit 24 is connected to the exhaust flow path 22 via a pressure adjustment unit 23. The pressure adjustment unit 23 includes a pressure adjustment valve such as a butterfly valve. The exhaust flow path 22 is configured so that the pressure inside the processing vessel 2 can be reduced by the exhaust unit 24. A transfer port 25 is provided on the side of the processing vessel 2. The transfer port 25 is configured to be freely opened and closed by a gate valve 26. The substrate W is loaded and unloaded between the processing vessel 2 and a transfer chamber (not shown) via the transfer port 25.

[0013] A mounting table 3 for holding a substrate W substantially horizontally is provided within the processing chamber 2. The mounting table 3 is substantially circular in plan view and supported by a support member 31. A substantially circular recess 32 for mounting a substrate W having a diameter of, for example, 300 mm is formed in the surface of the mounting table 3. The recess 32 has an inner diameter slightly larger (for example, about 1 mm to 4 mm) than the diameter of the substrate W. The depth of the recess 32 is configured to be substantially the same as the thickness of the substrate W. The mounting table 3 is made of a ceramic material such as aluminum nitride (AlN). Alternatively, the mounting table 3 may be made of a metal material such as nickel (Ni). Note that instead of the recess 32, a guide ring for guiding the substrate W may be provided around the periphery of the surface of the mounting table 3.

[0014] A grounded lower electrode 33, for example, is embedded in the mounting table 3. A temperature adjustment mechanism 34 is embedded below the lower electrode 33. The temperature adjustment mechanism 34 adjusts the temperature of the substrate W placed on the mounting table 3 to a set temperature based on a control signal from the control unit 9. If the mounting table 3 is made entirely of metal, the entire mounting table 3 functions as the lower electrode, so the lower electrode 33 does not need to be embedded in the mounting table 3. The mounting table 3 is provided with a plurality of (for example, three) lifting pins 41 for holding and lifting the substrate W placed on the mounting table 3. The lifting pins 41 are made of a material such as alumina (Al ２ O ３ The lift pins 41 may be made of ceramics such as quartz or the like. The lower ends of the lift pins 41 are attached to a support plate 42. The support plate 42 is connected to a lift mechanism 44 provided outside the processing vessel 2 via a lift shaft 43.

[0015] The lifting mechanism 44 is installed, for example, at the bottom of the exhaust chamber 21. The bellows 45 is provided between the lifting mechanism 44 and an opening 211 for the lifting shaft 43 formed in the bottom surface of the exhaust chamber 21. The support plate 42 may be shaped so that it can be raised and lowered without interfering with the support member 31 of the mounting table 3. The lifting pins 41 are configured to be able to be raised and lowered between the upper side and the lower side of the surface of the mounting table 3 by the lifting mechanism 44. In other words, the lifting pins 41 are configured to be able to protrude from the top surface of the mounting table 3.

[0016] A gas supply unit 5 is provided on the ceiling wall 27 of the processing vessel 2 via an insulating member 28. The gas supply unit 5 serves as an upper electrode and faces the lower electrode 33. An RF power supply 51 is connected to the gas supply unit 5 via a matching box 511. The frequency band of the RF power supply 51 is, for example, 450 kHz to 2.45 GHz. By supplying RF power from the RF power supply 51 to the upper electrode (gas supply unit 5), an RF electric field is generated between the upper electrode (gas supply unit 5) and the lower electrode 33. The gas supply unit 5 includes a hollow gas diffusion chamber 52. A number of holes 53 are arranged, for example, evenly, on the bottom surface of the gas diffusion chamber 52 for dispersing and supplying the processing gas into the processing vessel 2. A heating mechanism 54 is embedded in the gas supply unit 5, for example, above the gas diffusion chamber 52. The heating mechanism 54 is heated to a set temperature by receiving power from a power supply unit (not shown) based on a control signal from the control unit 9.

[0017] A gas supply path 6 is provided in the gas diffusion chamber 52. The gas supply path 6 is in communication with the gas diffusion chamber 52. A gas source 61 is connected to the upstream side of the gas supply path 6 via a gas line 62. The gas source 61 includes, for example, supply sources of various process gases, mass flow controllers, and valves (none of which are shown). The various process gases include gases used in the above-described method for forming a silicon-containing film. The various process gases are introduced from the gas source 61 into the gas diffusion chamber 52 via the gas line 62.

[0018] The various process gases include a first process gas containing a metal-containing precursor gas and a second process gas containing a halogen-containing precursor gas. The first process gas is a process gas used to form a metal-containing layer 210 (see FIG. 3A) in step S102 (see FIG. 2) described later. The second process gas is a process gas used to form a halogen-containing layer 220 (see FIG. 3A) in step S103 (see FIG. 2) described later. Details of the first process gas and the second process gas will be described later.

[0019] The substrate processing apparatus 1 includes a control unit 9. The control unit 9 is, for example, a computer, and includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), an auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or the auxiliary storage device, and controls the operation of the substrate processing apparatus 1. The control unit 9 may be provided inside or outside the substrate processing apparatus 1. When the control unit 9 is provided outside the substrate processing apparatus 1, the control unit 9 can control the substrate processing apparatus 1 via communication means such as wired or wireless.

[0020] Although the substrate processing apparatus 1 has been described as a substrate processing apparatus that generates capacitively coupled plasma (CCP), the present invention is not limited to this. It may also be a substrate processing apparatus that generates remote plasma using radio frequency (RF, VHF) or microwave (MW). Furthermore, the substrate processing apparatus that generates remote plasma may be a substrate processing apparatus that generates remote plasma within a processing vessel that accommodates a substrate W, or a substrate processing apparatus that supplies the generated remote plasma into the processing vessel that accommodates a substrate W.

[0021] <Substrate Processing Method> Next, an example of a substrate processing method will be described with reference to Fig. 2 and Figs. 3A to 3C. Fig. 2 is a flowchart showing an example of a substrate processing method according to this embodiment. Figs. 3A to 3C are example schematic cross-sectional views of a substrate W on which a resist film 230 having an opening pattern has been formed by the substrate processing method according to this embodiment.

[0022] In step S101, a substrate W is prepared. The substrate W has an underlayer 200 (see FIG. 3A ). The controller 9 controls a transfer device (not shown) to transfer the substrate W having the underlayer 200 to the processing chamber 2 of the substrate processing apparatus 1 and place it in the recess 32 of the mounting table 3.

[0023] In step S102, a metal-containing layer 210 is formed on the substrate W. Here, the control unit 9 controls the gas source 61 to supply a first process gas from the gas supply unit 5 into the process chamber 2 through the multiple holes 53. The control unit 9 also controls the RF power supply 51 to supply RF power to the upper electrode (gas supply unit 5). This generates plasma of the first process gas in the process chamber 2, and the substrate W is exposed to the generated plasma, thereby forming the metal-containing layer 210 on the surface of the substrate W. The metal-containing layer 210 is preferably a metal-containing polymer layer. The metal-containing polymer layer contains metal (M), carbon (C), and hydrogen (H). The metal-containing polymer layer preferably contains many C—H bonds. By forming the metal-containing polymer layer at a low temperature, a film containing a large amount of hydrogen (H), in other words, a film containing a large amount of C—H bonds, is formed.

[0024] Here, the first process gas contains a metal-containing precursor gas. The metal-containing precursor gas is a gas containing a metal (M) and hydrogen (H). Alternatively, the metal-containing precursor gas is a gas containing a metal (M), carbon (C), and hydrogen (H). In other words, the metal-containing precursor gas is a gas represented by the chemical formula M Ｘ C Ｙ H Ｚ where M is a metal, X and Z are integers of 1 or more, and Y is 0 or an integer of 1 or more. Here, the metal (M) is one selected from Sn, Sb, In, Al, Ti, Mn, Ta, Hf, and W.

[0025] Specifically, the metal-containing precursor gas is Sn(CH ３ ) ４ , SnH(CH ３ ) ３ , SnH ２ (CH ３ ) ２ , Sn(C ２ H ５ ) ４ , Al(CH３ ) ３ , Co(C ５ H ５ ) ２ , SnR ４ , SnHR ３ , (wherein R is -CH ３ , -C ２ H ３ , -C ３ H ５ , -C ４ H ７ , -C ６ H ６ ) is one selected from.

[0026] The first process gas may contain an additive gas and / or an inert gas. The additive gas may be H ２ , C ２ H ２ HCl. The inert gas is He, Ar, Ne, Xr, N ２ At least one gas selected from:

[0027] An example of a recipe for the process of forming the metal-containing layer 210 is shown below.

[0028] Plasma type: CCP, 13.56 MHz, 10 W to 500 W; Temperature of mounting table: 250°C or less; Pressure inside processing chamber: 100 mTorr to 20 Torr

[0029] In step S103, a halogen-containing layer 220 is formed on the substrate W. Here, the control unit 9 controls the gas source 61 to supply a second process gas from the gas supply unit 5 into the process chamber 2 through the multiple holes 53. The control unit 9 also controls the RF power supply 51 to supply RF power to the upper electrode (gas supply unit 5). This generates plasma of the second process gas in the process chamber 2, and the substrate W is exposed to the generated plasma, thereby forming a halogen-containing layer 220 on the surface of the substrate W. The halogen-containing layer 220 is preferably a halogen-containing polymer layer. The halogen-containing polymer layer contains halogen (Ha), carbon (C), and hydrogen (H). The halogen-containing polymer layer preferably contains many C—H bonds. By forming the halogen-containing polymer layer at a low temperature, a film containing a large amount of hydrogen (H), in other words, a film containing a large amount of C—H bonds, is formed.

[0030] Here, the second process gas contains a halogen-containing precursor gas. The halogen-containing precursor gas is a gas containing carbon (C) and halogen (Ha). Alternatively, the halogen-containing precursor gas is a gas containing carbon (C), hydrogen (H) and halogen (Ha). In other words, the halogen-containing precursor gas is a gas represented by the chemical formula C α H β Ha γ where Ha is a halogen, α and γ are integers of 1 or more, and β is 0 or an integer of 1 or more. Here, the halogen (Ha) is one selected from Cl, F, Br, and I.

[0031] Specifically, the halogen-containing precursor gas is C ２ H ２ Cl ２ , C ２ HCl ３ , CCl ４ The one selected from:

[0032] The second process gas may also contain an additive gas and / or an inert gas. The additive gas may be H ２ , C ２ H ２ HCl. The inert gas is He, Ar, Ne, Xr, N ２At least one gas selected from:

[0033] An example of a recipe for the process of forming the halogen-containing layer 220 is shown below.

[0034] Plasma type: CCP, 13.56 MHz, 10 W to 500 W; Temperature of mounting table: 250°C or less; Pressure inside processing chamber: 100 mTorr to 20 Torr

[0035] In step S104, it is determined whether the processes of steps S102 and S103 have been repeated a predetermined number of times. If they have not been repeated the predetermined number of times (S103: NO), the process returns to step S102, and the formation of the metal-containing layer 210 (S102) and the formation of the halogen-containing layer 220 (S103) are repeated. If they have been repeated the predetermined number of times (S103: YES), the process proceeds to step S105. Here, the control unit 9 controls a transfer device (not shown) to unload the substrate W from the processing chamber 2 of the substrate processing apparatus 1.

[0036] Through the above processing, a resist film 230 having a layered structure (in other words, a laminate structure) in which thin metal-containing layers 210 and thin halogen-containing layers 220 are alternately stacked is formed on the underlayer 200 of the substrate W. The process of forming the metal-containing layer 210 on the substrate W (step S102) and the process of forming the halogen-containing layer 220 on the substrate W (step S103) are performed in the same processing chamber 2 (see FIG. 1 ).

[0037] The thickness of one metal-containing layer 210 is preferably 2 nm or less. The thickness of one halogen-containing layer 220 is preferably 2 nm or less. The thickness of the laminated resist film 230 is preferably 20 nm or less, and more preferably 15 nm or less. By laminating thin films, as will be described later with reference to FIG. 5 , secondary electrons 312 emitted from the metal that absorbed EUV 311 can efficiently reach the halogen-containing layer 220 above and the halogen-containing layer 220 below the metal-containing layer 210. Furthermore, halogen and hydrogen dissociated by the secondary electrons 312 can efficiently reach the metal-containing layer 210 above and the metal-containing layer 210 below the halogen-containing layer 220.

[0038] 2, the substrate processing method is described as forming the metal-containing layer 210 first, then the halogen-containing layer 220, and repeating the same steps, but is not limited to this. The substrate processing method may be configured to form the halogen-containing layer 220 first, then the metal-containing layer 210, and repeat the same steps.

[0039] 3A , the example has been described in which the bottom layer of the resist film 230 (the layer in contact with the base layer 200) is the metal-containing layer 210. That is, the metal-containing layer 210 is formed on the base layer 200, and the halogen-containing layer 220 is formed on the metal-containing layer 210. The structure of the resist film 230 is not limited to this. The bottom layer of the resist film 230 may be the halogen-containing layer 220. That is, the halogen-containing layer 220 may be formed on the base layer 200, and the metal-containing layer 210 may be formed on the halogen-containing layer 220. Also, in FIG. 3A , the example has been described in which the top layer of the resist film 230 is the metal-containing layer 210, but this is not limiting, and the top layer of the resist film 230 may be the halogen-containing layer 220.

[0040] In step S105, the substrate W on which the resist film 230 having a laminated structure is formed on the underlayer 200 is subjected to an EUV exposure process. Here, in a nitrogen atmosphere, the resist film 230 of the substrate W is irradiated with EUV (Extreme Ultraviolet) through a photomask having a predetermined pattern, thereby forming an exposed portion 310 (see FIG. 3B ) in which the resist film 230 is irradiated with EUV and an unexposed portion 320 (see FIG. 3B ) that is not irradiated with EUV in the resist film 230.

[0041] In step S106, the substrate W that has been subjected to the EUV exposure process is subjected to a development process. Here, the development process selectively removes the exposed portion 310 (see FIG. 3C ) of the resist film 230. The development process can be at least one of a wet process and a dry process.

[0042] When the development process is a wet process, the substrate W is exposed to an organic solvent to selectively remove the exposed portion 310 of the resist film 230. The organic solvent may be, for example, alcohol.

[0043] When the development process is a dry process, the substrate W is exposed to a halogen-containing gas to selectively remove the exposed portion 310 (see FIG. 3C ) of the resist film 230. The halogen-containing gas may be at least one of HBr and HCl.

[0044] In step S107, the developed substrate W is subjected to a water vapor bake treatment. Here, the developed substrate W is heat-treated (baked) in a water vapor atmosphere. By performing the heat treatment in the water vapor atmosphere, the resist film 230 in the unexposed portion 320 is oxidized.

[0045] Alternatively, after the heat treatment is performed in a water vapor atmosphere, a further heat treatment may be performed in a nitrogen atmosphere.

[0046] As described above, according to the substrate processing method shown in FIG. 2, the resist film 230 can be formed on the underlayer 200.

[0047] Here, the resist film 230 formed in the substrate processing apparatus 1 can be a positive resist film that can selectively remove the exposed portion 310. For example, when forming a contact hole or the like in the underlayer 200, a positive resist film can be preferably used compared to a negative resist film.

[0048] The resist film 230 formed in the substrate processing apparatus 1 can be formed by a plasma-based chemical vapor deposition method, which allows the resist film to be formed thinner than a resist film formed by applying a polymer.

[0049] Furthermore, by forming the resist film 230 to a thin thickness, when a pattern is formed on the base layer 200 using the resist film 230 having an opening pattern as a mask, the occurrence of pattern collapse formed on the base layer 200 can be suppressed.

[0050] <Processing of Resist Film> Next, the processing of the resist film 230 formed by the substrate processing apparatus 1 will be further described with reference to Figs. 4 to 6. Fig. 4 is a diagram schematically showing the structure of the resist film 230 having a laminated structure formed by the substrate processing apparatus 1 according to this embodiment. Fig. 5 is a diagram schematically showing the structure of the resist film 230 in the exposed portion 310 in each process. Fig. 6 is a diagram schematically showing the structure of the resist film 230 in the unexposed portion 320 in each process.

[0051] 4 to 6 and the following description, tetramethyltin: Sn(CH ３ ) ４ as a halogen-containing precursor gas, and chloroethylene:C ２ H ２ Cl ２ The following will explain the case where the above is used as an example.

[0052] As shown in FIG. 4, the process of step S102 ３ ) ４ The metal-containing layer 210 is formed by bonding the C ２ H ２ Cl ２ are bonded to form a halogen-containing layer 220. Then, by repeating the process of step S102 and the process of step S103, metal-containing layers 210 and halogen-containing layers 220 are alternately stacked to form a resist film 230 (see FIG. 3A).

[0053] Next, in step S105, an exposure process is performed on the substrate W. Here, the exposure process is performed by irradiating the resist film 230 on the substrate W with EUV light having a wavelength of 13 nm and high-energy photons of 95 eV through a photomask having a predetermined pattern.

[0054] 5A and 5B are diagrams schematically illustrating the structure of the resist film 230 in the exposure section 310 during exposure processing. As shown in Fig. 5A, EUV light 311 irradiated onto the substrate W is absorbed by metal atoms (Sn) in the metal-containing layer 210, causing the metal atoms (Sn) to emit secondary electrons 312.

[0055] The emitted secondary electrons 312 activate Sn-C bonds between metal atoms (Sn) and carbon (C) surrounding the metal atoms (Sn). The emitted secondary electrons 312 also reach the upper and lower halogen-containing layers 220 from the metal-containing layer 210, activating C-Cl bonds and C-H bonds in the halogen-containing layer 220 and releasing halogen (Cl) and hydrogen (H). The halogen-containing layer 220 is preferably a halogen-containing polymer layer containing many C-H bonds. The halogen-containing layer 220 containing many hydrogen (H) easily decomposes upon exposure to EUV and secondary electrons, releasing halogen (Cl) and hydrogen (H).

[0056] The halogen (Cl) and hydrogen (H) released from the halogen-containing layer 220 bond with the activated metal atoms (Sn) of the metal-containing layer 210, and some of the stable Sn—C bonds are converted into SnH Ｎ Cl Ｍ (at least one of N and M is an integer of 1 or more). This changes the structure to an unstable structure that is released in the subsequent development process. Furthermore, the metal-containing layer 210 is preferably a metal-containing polymer layer containing many C—H bonds. A metal-containing polymer layer containing many C—H bonds bonds with halogen (Cl) and hydrogen (H) released from the halogen-containing layer 220, thereby improving solubility in the development process.

[0057] 6( a) and 6(b) are diagrams schematically illustrating the structure of the resist film 230 in the unexposed portion 320 during the exposure process. As shown in Fig. 6(a) and 6(b), the metal-containing layer 210 and the halogen-containing layer 220 in the unexposed portion 320 maintain a stable and strong bond, similar to the state shown in Fig. 4.

[0058] Next, in step S106, the substrate W is subjected to a development process.

[0059] Fig. 5C is a diagram schematically illustrating the structure of the resist film 230 in the exposed portion 310 during the development process. In the exposed portion 310, the structure is changed to an unstable structure by the exposure process as shown in Fig. 5B, and the resist film 230 in the exposed portion 310 is dissolved and removed as shown in Fig. 5C.

[0060] 6C is a diagram schematically illustrating the structure of the resist film 230 in the unexposed portion 320 during the development process. In the unexposed portion 320, as shown in FIG. 6B, stable and strong bonds are maintained even after the exposure process, and as shown in FIG. 6C, the resist film 230 in the unexposed portion 320 remains without being removed by the development process.

[0061] Next, in step S107, the substrate W is subjected to an oxidation annealing process (steam baking process). FIG. 6D is a diagram schematically showing the structure of the resist film 230 in the unexposed portion 320 in the oxidation annealing process. Here, the oxidizing agent (O ２ and / or H ２ O) is supplied to the substrate W to perform an annealing treatment. As a result, the thin metal-containing layer 210 containing the metal atom Sn is transformed into a stable oxide film of metal oxide (SnO). That is, the metal-containing layer 210 becomes a SnOCH film. Metal oxide films have excellent etching resistance even in dry etching. Therefore, the resist film 230 transformed into a metal oxide film can be used as a mask to suitably dry etch the underlayer 200. In other words, the resist film 230 functions as a hard mask. This eliminates the step of forming a hard mask between the resist film and the underlayer 200 to be processed, thereby reducing the cost of substrate processing.

[0062] Although the example has been described in which the resist film 230 in which the metal-containing layer 210 and the halogen-containing layer 220 are alternately laminated is formed by plasma CVD, the present invention is not limited to this. A configuration in which the resist film 230 in which the metal-containing layer 210 and the halogen-containing layer 220 are alternately laminated by thermal CVD may also be used. Alternatively, a process in which the resist film 230 in which the metal-containing layer 210 and the halogen-containing layer 220 are alternately laminated may be used, such as a process in which remote plasma is used to form the resist film 230. Alternatively, the metal-containing layer 210 and the halogen-containing layer 220 may be formed by different film formation methods. Alternatively, the metal-containing layer 210 may be formed by physical vapor deposition (PVD).

[0063] The metal-containing precursor gas may be a gas containing a halogen (Ha) in addition to a metal (M), carbon (C), and hydrogen (H). Ｗ Ha Ｘ C Ｙ H Ｚ where M is a metal, Ha is a halogen, W is an integer of 1 or more, and X, Y, and Z are 0 or integers of 1 or more. Specifically, the metal-containing precursor gas is SnH ４ , SnH ３ Cl, SnCl ３ C ４ H ９ , AlCl ３ , Al(C ２ H ５ ) ２ Cl, TiCl ４ , TaCl ５ , GeH ４ , Ge(CH ３ ) ４ It is one selected from:

[0064] The metal-containing precursor gas may be a gas containing nitrogen (N) and / or oxygen (O) in addition to metal (M), carbon (C), and hydrogen (H). Ｖ N Ｗ H Ｘ C Ｙ O Ｚ where M is a metal, V is an integer of 1 or more, and W, X, Y, and Z are 0 or integers of 1 or more. Specifically, the metal-containing precursor gas is Sn(N(CH ３ ) ２ ) ４ , Sn(O-C ４ H ９ ) ４ , Al(N(CH ３ ) ２ ) ３ , Ti(N(CH ３ ) ２ ) ４ , Ta(N(CH ３ ) ２ ) ５ , Hf(N(CH ３ ) ２ ) ４ , Al(CH３ ) ２ O.C. ３ H ７ It is one selected from:

[0065] The metal-containing precursor gas may also be a combination of these gases.

[0066] The second process gas is a compound represented by the chemical formula C α H β Ha γ and a halogen-containing precursor gas represented by chemical formula C Ｘ H Ｙ The additive gas may be a mixed gas with an additive gas represented by the formula: Ha is a halogen, α and γ are integers of 1 or more, and β is 0 or an integer of 1 or more. Here, the halogen (Ha) is one selected from Cl, F, Br, and I. X and Y are integers of 1 or more. For example, the additive gas may be C ２ H ２ and the second process gas is C ２ H ２ Cl ２ and C ２ H ２ By adding an additive gas to the second process gas, a stable halogen-containing layer can be formed.

[0067] The second process gas is a compound represented by the chemical formula C α H β Ha γ and a halogen-containing precursor gas represented by chemical formula C Ｘ H Ｙ and the chemical formula Ha Ｍ H Ｎ The additive gas may be a mixed gas with an additive gas represented by the formula: Ha is a halogen, α and γ are integers of 1 or more, and β is an integer of 0 or 1 or more. Here, the halogen (Ha) is one selected from Cl, F, Br, and I. X and Y are integers of 1 or more. M is an integer of 1 or more, and N is an integer of 0 or 1 or more. For example, the additive gas may be C ２ H ２ And Cl ２ The second process gas is a mixed gas of C and one gas selected from the group consisting of C, ... ２ H ２ Cl２ , C ２ H ２ , and Cl ２ Mixture of gases, C ２ H ２ Cl ２ , C ２ H ２ The additive gas may be a mixture of HCl and HCl. A stable halogen-containing layer can be formed by adding an additive gas to the second process gas.

[0068] Alternatively, the resist film 230 may have a laminated structure including a metal-containing layer 210, a halogen-containing layer 220, and an organic film (hydrocarbon layer). That is, the process of forming a laminated structure film (resist film) may further include a process of forming a hydrocarbon layer (not shown) on the substrate W in addition to a process of forming a metal-containing layer 210 on the substrate W (see step S102) and a process of forming a halogen-containing layer 220 on the substrate W (see step S103). These processes may be repeated to form a laminated structure film (resist film) on the substrate W. Preferably, the process of forming a hydrocarbon layer (not shown) on the substrate W is performed after the process of forming the metal-containing layer 210 on the substrate W (see step S102) and before the process of forming the halogen-containing layer 220 on the substrate W (see step S103). Forming a hydrocarbon layer between the metal-containing layer 210 and the halogen-containing layer 220 can suppress reaction between the metal in the metal-containing layer 210 and the halogen in the halogen-containing layer 220. The uppermost layer of the resist film 230 may be the halogen-containing layer 220 or a thick layer of an organic film (hydrocarbon layer), which can prevent natural oxidation of the metal-containing layer 210 before the exposure process and development process.

[0069] The above describes the substrate processing apparatus 1 and the substrate processing method according to this embodiment, but the present disclosure is not limited to the above-described embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure as set forth in the claims.

[0070] This application claims priority based on Japanese Patent Application No. 2023-110189 filed on July 4, 2023, the entire contents of which are incorporated herein by reference.

[0071] REFERENCE SIGNS LIST 1 Substrate processing apparatus 200 Underlayer 210 Metal-containing layer 220 Halogen-containing layer 230 Resist film (laminated structure film) 310 Exposed portion 311 EUV 312 Secondary electrons 320 Unexposed portion W Substrate

Claims

1. A substrate processing method comprising the steps of: forming a laminated structure film on a substrate, the laminated structure film being formed by laminating a metal-containing layer and a halogen-containing layer; irradiating the laminated structure film with extreme ultraviolet light in a predetermined pattern to form exposed areas in the laminated structure film that have been irradiated with the extreme ultraviolet light and unexposed areas in the laminated structure film that have not been irradiated with the extreme ultraviolet light; and selectively removing the exposed areas of the laminated structure film.

2. The substrate processing method according to claim 1, wherein the metal-containing layer is formed by supplying a first processing gas containing a metal-containing precursor gas to generate plasma, and exposing the substrate to the generated plasma.

3. The metal-containing precursor gas is represented by the chemical formula M Ｘ C Ｙ H Ｚ 3. The method of claim 2, wherein M is a metal, X and Z are integers of 1 or more, and Y is 0 or an integer of 1 or more.

4. The metal-containing precursor gas is represented by the chemical formula M Ｗ Ha Ｘ C Ｙ H Ｚ 3. The substrate processing method according to claim 2, wherein M is a metal, Ha is a halogen, W is an integer of 1 or more, and X, Y, and Z are 0 or integers of 1 or more.

5. The metal-containing precursor gas is represented by the chemical formula M Ｖ N Ｗ H Ｘ C Ｙ O Ｚ 3. The substrate processing method according to claim 2, wherein M is a metal, V is an integer of 1 or more, and W, X, Y, and Z are 0 or integers of 1 or more.

6. The substrate processing method according to any one of claims 3 to 5, wherein the metal (M) is one selected from the group consisting of Sn, Sb, In, Al, Ti, Mn, Ta, Hf and W.

7. The metal-containing precursor gas is Sn(CH ３ ), SnH(CH ４ ), SnH ３ (CH ３ ), Sn(C ２ H ３ ), Al(CH ２ ), Co(C ２ H ５ ), SnR ４ ), SnHR ３ ), (where R is -CH ３ ), -C ５ H ５ ), -C ２ H ４ ), -C ３ H ３ ), -C ２ H ３ ), -C ３ H ５ ), -C ４ H ７ ), -C ６ H ６ ), SnH ４ ), SnH ３ Cl, SnCl ３ C ４ H ９ ), AlCl ３ ), Al(C ２ H ５ ) ２ Cl, TiCl ４ ), TaCl ５ ), GeH ４ ), Ge(CH ３ ) ４ ), Sn(N(CH ３ )) ２ ), Sn(O-C ４ H ４ ) ９ ), Al(N(CH ４ )) ３ ), Ti(N(CH ２ )) ３ ), Ta(N(CH ３ )) ２ ), Hf(N(CH ４ )) ３ ), Al(CH ２ ) ５ OC​​​​​​​​​​ ３ H ７ The substrate processing method according to claim 2 , wherein the substrate processing method is one selected from the group consisting of:

8. The substrate processing method according to claim 1, wherein the halogen-containing layer is formed by supplying a second processing gas containing a halogen-containing precursor gas to generate plasma, and exposing the substrate to the generated plasma.

9. The halogen-containing precursor gas is represented by the chemical formula C α H β Ha γ 9. The substrate processing method according to claim 8, wherein Ha is a halogen, α and γ are integers of 1 or more, and β is 0 or an integer of 1 or more.

10. The substrate processing method according to claim 9, wherein the halogen (Ha) is one selected from the group consisting of Cl, F, Br, and I.

11. The halogen-containing precursor gas is ２ H ２ C ２ , C ２ HCl ３ , CCl ４ The substrate processing method according to claim 8 , wherein the substrate processing method is one selected from the following:

12. The method of claim 8, wherein the second process gas further comprises an additive gas.

13. The additive gas is a gas having the chemical formula C Ｘ H Ｙ The substrate processing method according to claim 12 , wherein X and Y are integers of 1 or more.

14. The additive gas is a gas having the chemical formula C Ｘ H Ｙ and the chemical formula Ha Ｍ H Ｎ 13. The substrate processing method according to claim 12, wherein Ha is a halogen, X, Y, and M are integers of 1 or more, and N is 0 or an integer of 1 or more, and the halogen (Ha) is one selected from the group consisting of Cl, F, Br, and I.

15. The additive gas is C ２ H ２ The method for processing a substrate according to claim 12 .

16. The additive gas is C ２ H ２ and Cl ２ or a mixture of C ２ H ２ The substrate processing method according to claim 12 , wherein the gas mixture is a mixture of HCl and H2O.

17. The substrate processing method according to claim 1, wherein the step of forming the laminated structure film comprises forming the metal-containing layer on the substrate, and forming the halogen-containing layer on the metal-containing layer.

18. The substrate processing method according to claim 1, wherein the step of forming the laminated structure film comprises forming the halogen-containing layer on the substrate, and forming the metal-containing layer on the halogen-containing layer.

19. The substrate processing method according to claim 1, wherein the step of forming the laminated structure film comprises repeating the step of forming the metal-containing layer and the step of forming the halogen-containing layer a plurality of times.

20. The substrate processing method according to claim 19, wherein the step of forming the metal-containing layer and the step of forming the halogen-containing layer are carried out in the same processing chamber.

21. The substrate processing method according to claim 1, wherein the step of forming the laminated structure film further includes the step of forming a hydrocarbon layer.

22. The substrate processing method according to claim 21, wherein the step of forming a hydrocarbon layer is performed after the step of forming a metal-containing layer and before the step of forming a halogen-containing layer.

23. The substrate processing method according to claim 21, wherein the step of forming the laminated structure film comprises forming the halogen-containing layer or the hydrocarbon layer on an uppermost layer.

24. The substrate processing method according to claim 1, wherein the step of forming the metal-containing layer and the step of forming the halogen-containing layer are carried out at a temperature of 250° C. or less.

25. The substrate processing method according to claim 1, wherein the thickness of one of the metal-containing layers is 2 nm or less, and the thickness of one of the halogen-containing layers is 2 nm or less.

26. The substrate processing method according to claim 1, wherein the laminated structure film has a thickness of 15 nm or less.

27. The substrate processing method according to claim 1, wherein the step of irradiating the laminated film with extreme ultraviolet rays is performed in a nitrogen atmosphere.

28. The substrate processing method according to claim 1, wherein the step of selectively removing the exposed portion is a wet process in which the substrate is exposed to an organic solvent to selectively remove the exposed portion.

29. The substrate processing method according to claim 1, wherein the step of selectively removing the exposed portion is a dry process in which the substrate is exposed to a halogen-containing gas to selectively remove the exposed portion.

30. The substrate processing method according to claim 1, further comprising the step of heat-treating the substrate after selectively removing the exposed portion.

31. The substrate processing method according to claim 1, wherein the step of heat-treating the substrate comprises heat-treating the substrate in a water vapor atmosphere.

32. The substrate processing method according to claim 31, further comprising the step of heat-treating the substrate in a nitrogen atmosphere after the heat-treating in the water vapor atmosphere.

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