Substrate processing method
By forming a photoresist film containing a first metal element on a substrate and using extreme ultraviolet light exposure and metal oxide mask treatment, the problem of positive pattern formation in the prior art is solved, achieving efficient formation of positive patterns on the substrate and improving the flexibility and accuracy of substrate processing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TOKYO ELECTRON LTD
- Filing Date
- 2024-12-24
- Publication Date
- 2026-07-31
AI Technical Summary
Existing technologies struggle to create positively patterned masks, leading to limitations in substrate processing methods.
By forming a photoresist film containing a first metal element on a substrate, exposing and unexposed areas are formed using extreme ultraviolet light, and a metal oxide film containing a second metal element is selectively formed on the upper surface of the unexposed area as a mask to remove the exposed area of the photoresist film, thus achieving the formation of a positive pattern.
It enables the mask formation of positive patterns on the substrate, improving the flexibility and accuracy of substrate processing.
Smart Images
Figure CN122497919A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a substrate processing method. Background Technology
[0002] Patent Document 1 discloses a method for manufacturing a semiconductor device, characterized by comprising: a step of depositing an organic insulating film on a semiconductor substrate; a step of selectively forming a silanized layer on the organic insulating film; and a step of etching the organic insulating film using the silanized layer as a mask to form a recess in the organic insulating film as a connection hole or wiring groove.
[0003] Existing technical documents
[0004] Patent documents
[0005] Patent Document 1: Japanese Patent Application Publication No. 2001-168192 Summary of the Invention
[0006] The technical problem that the invention aims to solve
[0007] In one aspect, the present invention provides a substrate processing method for forming a mask with a positive pattern.
[0008] Means for solving technical problems
[0009] To solve the above-mentioned technical problems, a substrate processing method is provided, characterized by comprising: a step of preparing a substrate having a photoresist film, wherein the photoresist film comprises 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 in the photoresist film; a step of supplying the substrate with a metal-containing gas containing a second metal element different from the first metal element, and forming 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.
[0010] Invention Effects
[0011] According to one aspect of the present invention, a substrate processing method for forming a positive pattern mask can be provided. Attached Figure Description
[0012] Figure 1 A flowchart illustrating an example of the substrate processing method of the first embodiment.
[0013] Figure 2 This is an example of a schematic diagram of the substrate used in each step.
[0014] Figure 3A This is an example of a schematic diagram of the substrate used in each step.
[0015] Figure 3B This is an example of a schematic diagram of the substrate used in each step.
[0016] Figure 4A This is an example of a schematic diagram of the substrate used in each step.
[0017] Figure 4B This is an example of a schematic diagram of the substrate used in each step.
[0018] Figure 5A This is an example of a schematic diagram of the substrate used in each step.
[0019] Figure 5B This is an example of a schematic diagram of the substrate used in each step.
[0020] Figure 6A This is an example of a schematic diagram of the substrate used in each step.
[0021] Figure 6B This is an example of a schematic diagram of the substrate used in each step.
[0022] Figure 7 A schematic diagram showing an example of a substrate processing apparatus.
[0023] Figure 8 A flowchart illustrating an example of film formation processing in a substrate processing apparatus.
[0024] Figure 9 A flowchart illustrating an example of the substrate processing method of the second embodiment.
[0025] Figure 10A This is an example of a schematic diagram of the substrate used in each step.
[0026] Figure 10B This is an example of a schematic diagram of the substrate used in each step.
[0027] Figure 11A This is an example of a schematic diagram of the substrate used in each step.
[0028] Figure 11B This is an example of a schematic diagram of the substrate used in each step.
[0029] Figure 12A This is an example of a schematic diagram of the substrate used in each step.
[0030] Figure 12B This is an example of a schematic diagram of the substrate used in each step.
[0031] Figure 13A This is an example of a schematic diagram of the substrate used in each step.
[0032] Figure 13B This is an example of a schematic diagram of the substrate used in each step.
[0033] Figure 14A This is an example of a schematic diagram of the substrate used in each step.
[0034] Figure 14B This is an example of a schematic diagram of the substrate used in each step. Detailed Implementation
[0035] Hereinafter, the embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals are used to label the same components, and repeated descriptions are omitted.
[0036] <First Implementation>
[0037] use Figures 1 to 6B An example of the substrate processing method of the first embodiment will be described. Figure 1 This is a flowchart illustrating an example of the substrate processing method of the first embodiment. Figures 2 to 6B This is an example of a schematic diagram of the substrate used in each step. Furthermore, Figure 2 This is a cross-sectional view of the substrate. Additionally, in Figure 3A , Figure 3B middle, Figure 3B This is a schematic diagram of the substrate viewed from above. Figure 3A It is along Figure 3B A schematic diagram of the cross-section of line AA cut off. Similarly, in Figure 4A , Figure 4B middle, Figure 4B This is a schematic diagram of the substrate viewed from above. Figure 4A It is along Figure 4B A schematic diagram of the cross-section of line AA cut off. Figure 5A , Figure 5B middle, Figure 5B This is a schematic diagram of the substrate viewed from above. Figure 5A It is along Figure 5B A schematic diagram of the cross-section of line AA cut off. Figure 6A , Figure 6B middle, Figure 6B This is a schematic diagram of the substrate viewed from above. Figure 6A It is along Figure 6B A schematic diagram of the cross-section of line AA cut off. Additionally, Figure 3B , 4B Although diagrams 5B and 6B are viewed from above, the labels and annotations for each component are different. Figure 3A , 4A The same shaded lines are used to illustrate the sections 5A and 6A.
[0038] In step S101, a substrate is prepared. Here, the prepared substrate includes a base film 310 (see reference). Figure 2 The base film 310 is disposed on the photoresist film 320 described later (see reference). Figure 2 The membrane below the base membrane 310. Additionally, the base membrane 310 is a mask 320A (see reference 320A) that can be formed with a pattern of openings 325 described later. Figure 6A , Figure 6B The substrate film 310 is a film whose opening pattern is transferred to the mask 320A through an etching process. The substrate film 310 can be, for example, a silicon-containing film (e.g., SOG (Spin On Glass) film) or a carbon-containing film (e.g., SOC (Spin On Carbon) film). Alternatively, the substrate film 310 can also be a laminated film obtained by stacking multiple films such as silicon-containing films and carbon-containing films. Furthermore, the substrate film 310, as a laminated film, can also have a BARC (Bottom Anti-Reflective Coating) or similar film. The substrate film 310 can, for example, be a film that can be used as a hard mask.
[0039] In step S102, a photoresist film 320 is formed on the substrate. Figure 2 This is an example of a schematic diagram of a substrate after the formation of the photoresist film 320.
[0040] Here, a photoresist film 320 is formed on the base film 310. The photoresist film 320 is a film containing a metal oxide comprising a first metal element. Alternatively, the photoresist film 320 can be a metal oxide photoresist containing a first metal element, or a resin photoresist (chemically amplified photoresist (CAR)) using a metal oxide containing a first metal element as a sensitizer, but is not limited to these. Here, the first metal element includes any one or more of Sn, W, Te, Zn, Zr, Sb, In, etc. The metal oxide can be, for example, SnO. x (x is any number), WO x (x is any number), TeO x (x is any number), ZnO x (x is any number), ZrO x (x is any number), SbO x (x is any number), InO x(x is any number) etc. Furthermore, during the exposure process described later (refer to S103), the valence or oxidation number of the first metal element changes when the photoresist film 320 is exposed to EUV (Extreme Ultraviolet). Additionally, the photoresist film 320 is a negative photoresist film.
[0041] In step S103, the substrate is exposed. Figure 3A , Figure 3B This is an example of a schematic diagram of a substrate after exposure processing.
[0042] Here, under a nitrogen atmosphere, EUV is applied to the photoresist film 320 of the substrate through a photomask (not shown) with a predetermined pattern. Thus, as... Figure 3A , Figure 3B As shown, an exposed portion 321 irradiated with EUV and an unexposed portion 322 not irradiated with EUV are formed in the photoresist film 320. Alternatively, it can be as described later. Figure 10A , Figure 10B As shown, the photoresist film 320 has a reaction layer 321a (fully exposed area) formed on the central side of the exposure area 321, and an unreacted layer 321b (intermediate exposure area) formed on the outer periphery of the exposure area 321. The reaction layer 321a is the area where the valence or oxidation number of the first metal element changes due to EUV exposure. The unreacted layer 321b is the area where EUV exposure is insufficient, and a portion of the first metal element whose valence or oxidation number has not changed remains. Furthermore, in the unexposed area 322, no EUV exposure is performed, and the first metal element whose valence or oxidation number has not changed remains.
[0043] In step S104, a process is performed to selectively form a metal oxide film 330 on the upper surface (exposed surface) of the unexposed portion 322 of the photoresist film 320. Figure 4A , Figure 4B This is an example of a schematic diagram of a substrate after selectively forming a metal oxide film 330. Furthermore, regarding the process for selectively forming the metal oxide film 330, the following will be used... Figures 7 to 8 This will be explained later. As a result, a metal oxide film 330 is formed on the upper surface of the unexposed portion 322. Furthermore, when the exposed portion 321 has a reaction layer 321a (fully exposed portion) and an unreacted layer 321b (intermediate exposed portion), a metal oxide film 330 is formed on the upper surfaces of the unexposed portion 322 and the unreacted layer 321b (intermediate exposed portion).
[0044] In step S105, a resist etching process is performed. Figure 5A , Figure 5B This is an example of a schematic diagram of a substrate after resist etching.
[0045] Here, the photoresist film 320 is etched using the metal oxide film 330 as a mask. This etches the exposure portion 321, forming a mask 320A with an opening 325. Alternatively, if the exposure portion 321 has a reactive layer 321a (fully exposed portion) and an unreacted layer 321b (intermediate exposed portion), the reactive layer 321a (fully exposed portion) is etched to form a mask 320A with an opening 325.
[0046] In step S106, a metal oxide film etching process is performed. Figure 6A , Figure 6B This is an example of a schematic diagram of a substrate after metal oxide film etching. Here, the metal oxide film 330 is removed by etching. Alternatively, if the metal oxide film 330 does not affect other processes, step S106 can be omitted.
[0047] As mentioned above, according to Figure 2 The substrate processing method shown can form a mask 320A on the substrate such that the exposed portion in the exposure process (S103) is an opening 325. That is, a mask 320A with a positive pattern can be formed on the substrate.
[0048] Next, use Figures 7 to 8 The process shown in step S104 will be explained.
[0049] First, use Figure 7 Here is an example of a substrate processing apparatus that performs the processing shown in step S104 on substrate W. Figure 7 This is a schematic diagram showing an example of a substrate processing apparatus.
[0050] The substrate processing apparatus includes a processing container 1, a mounting stage 2, a spray head 3, an exhaust unit 4, a gas supply unit 5, and a control unit 6.
[0051] The processing container 1 is made of a metal such as aluminum and has a generally cylindrical shape. The processing container 1 is capable of accommodating the substrate W. An inlet / outlet 11 for feeding or discharging the substrate W is formed on the side wall of the processing container 1. The inlet / outlet 11 can be opened and closed by a gate valve 12. An annular exhaust pipe 13 with a rectangular cross-section is provided on the main body of the processing container 1. A slit 13a is formed along the inner circumferential surface of the exhaust pipe 13. An exhaust port 13b is formed on the outer wall of the exhaust pipe 13. A top wall 14 is provided on the upper surface of the exhaust pipe 13 to close the upper opening of the processing container 1. The exhaust pipe 13 and the top wall 14 are airtightly sealed by a sealing ring 15.
[0052] The mounting stage 2 horizontally supports the substrate W within the processing container 1. The mounting stage 2 is a circular plate larger than the substrate W and is constructed of ceramic materials such as aluminum nitride (AlN) or metallic materials such as aluminum or nickel alloys. A heater 21 for heating the substrate W is embedded inside the mounting stage 2. The heater 21 is powered by a heater power supply (not shown). By controlling the output of the heater 21 using the temperature signal from a thermocouple (not shown) located near the upper surface of the mounting stage 2, the substrate W can be controlled to a predetermined temperature. A cover member 22 made of ceramic such as alumina is provided on the mounting stage 2 to cover the outer peripheral area and sides of the upper surface.
[0053] The platform 2 is supported by a support member 23. The support member 23 extends downwards from the center of the bottom surface of the 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 platform 2 can be lifted by the lifting mechanism 24. Figure 7 The processing position, indicated by a solid line, moves up and down between the transport position (indicated by a double-dotted line below) where the substrate W can be transported. A flange 25 is mounted below 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 25. The bellows 26 separates the atmosphere inside the processing container 1 from the outside air and can extend and retract as the platform 2 moves up and down.
[0054] Near the bottom surface of the processing container 1, three (two shown only) wafer support pins 27 are provided, protruding upwards from the lifting plate 27a. The wafer support pins 27 can be raised and lowered via the lifting plate 27a by a lifting mechanism 28 located below the processing container 1. The wafer support pins 27 can be inserted into through holes 2a provided in the mounting stage 2 located at the transport position, protruding or submerged relative to the upper surface of the mounting stage 2. By raising and lowering the wafer support pins 27, the substrate W can be transferred between the transport robot (not shown) and the mounting stage 2.
[0055] The spray head 3 supplies processing gas into the processing container 1 in a spray pattern. The spray head 3 is made of, for example, metal and is arranged opposite to the mounting platform 2. The spray head 3 has approximately the same diameter as the mounting platform 2. The spray head 3 includes a main body 31 and a spray plate 32. The main body 31 is fixed to the lower surface of the top wall 14. The spray plate 32 is connected below the main body 31. A gas diffusion space 33 is formed between the main body 31 and the spray plate 32. A gas inlet hole 36 is provided in the gas diffusion space 33, penetrating the center of the top wall 14 and the main body 31. A downwardly protruding annular protrusion 34 is formed on the periphery of the spray plate 32. A plurality of gas release holes 35 are formed on the flat surface inside the annular protrusion 34 in the spray plate 32.
[0056] With the platform 2 in the processing position, a processing space 38 is formed between the platform 2 and the spray plate 32, and the upper surface of the covering member 22 approaches the annular protrusion 34 to form an annular gap 39.
[0057] The exhaust unit 4 is capable of venting the interior of the processing container 1. The exhaust unit 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 is capable of venting the gas inside the processing container 1 via the exhaust pipe 13 and the exhaust pipe 41.
[0058] The gas supply unit 5 is capable of supplying various gases to the spray head 3. The gas supply unit 5 has a gas supply source 51. The gas supply source 51 is capable of supplying various processing gases to the processing space 38 through the gas inlet 36 and the gas diffusion space 33 from the gas outlet 35.
[0059] The control unit 6 is, for example, a computer, including a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), and auxiliary storage devices. The CPU can operate according to a program stored in the ROM or auxiliary storage devices, thereby controlling the operation of the substrate processing device. The control unit 6 can be located inside or outside the substrate processing device. When the control unit 6 is located outside the substrate processing device, it can control the substrate processing device via a wired or wireless communication network.
[0060] Next, use Figure 8 An example of film formation processing in a substrate processing apparatus will be described. Figure 8 This is a flowchart illustrating an example of film formation processing in a substrate processing apparatus.
[0061] In step S201, a substrate is prepared. Here, the prepared substrate is as follows: Figure 3A , Figure 3B As shown, the photoresist film 320 has an exposed portion 321 and an unexposed portion 322.
[0062] 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 container 1. The second metal element includes any one or more of Al, Ti, Ga, Ru, Hf, and Sn, W, Te, Zn, Zr, Sb, In, etc., which are only included when not used as the first metal element. In other words, when any one of "Sn, W, Te, Zn, Zr, Sb, In" is selected as the first metal element, the second metal element can be any one of the elements other than those selected as the first metal element from "Al, Ti, Ga, Ru, Hf" and "Sn, W, Te, Zn, Zr, Sb, In". For example, the metal-containing gas containing the second metal element includes TMA (trimethylaluminum), TDMAT (tetra(dimethylamino)titanium), TEGa (triethylgallium), Ru3CO. 12 One or more of the following. In addition, by setting the temperature to a temperature lower than the temperature at which the metal-containing gas forms a film due to thermal decomposition, it is possible to suppress the formation of a metal oxide film 330 on the upper surface of the exposure section 321.
[0063] On the other hand, on the upper surface of the unexposed portion 322, by using the first metal element whose valence or oxidation number has not changed and which remains in the unexposed portion 322 as a catalyst, a metal-containing gas containing a second metal element is reacted, and the precursor of the metal-containing gas can be decomposed, and a metal oxide film (containing a metal film) 330 is selectively formed on the upper surface of the unexposed portion 322.
[0064] 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 container 1. The inert gas is a gas that is inert relative to the photoresist film 320 and the metal-containing gas. The inert gas includes any one or more of nitrogen (N2), Ar, and He. Here, the inert gas is used to purge the metal-containing gas physically adsorbed on the upper surface of the exposure unit 321.
[0065] In step S204, the control unit 6 determines whether the processes in steps S202 and S203 have been repeated a predetermined number of times. If the predetermined number of repetitions has not been performed (S204, "No"), the control unit 6 returns to step S202 and repeats the process. Here, when the thickness of the metal oxide film 330 reaches a predetermined thickness (e.g., approximately 1 nm), the catalytic effect of the unexposed portion 322 disappears, and the growth of the metal oxide film 330 stops. Thus, the thickness of the metal oxide film 330 can be appropriately controlled. If the predetermined number of repetitions has been performed (S204, "Yes"), the control unit 6 terminates the process.
[0066] As mentioned above, according to Figure 8 The film-forming method shown can selectively form a metal oxide film 330 on the upper surface of the unexposed portion 322 relative to the upper surface of the exposed portion 321. Furthermore, when the exposed portion 321 has a reaction layer 321a (fully exposed portion) and an unreacted layer 321b (intermediate exposed portion), the metal oxide film 330 can be selectively formed on the upper surfaces of the unexposed portion 322 and the upper surfaces of the unreacted layer 321b (intermediate exposed portion) relative to the upper surface of the reaction layer 321a (fully exposed portion).
[0067] Furthermore, the above description illustrates the case where a metal-containing gas containing a second metal element is supplied as a precursor gas (film-forming gas) in step S202, thereby forming a metal oxide film 330 containing a second metal element on the unexposed portion 322 and the upper surface of the unreacted layer 321b. However, this is not a limitation. Alternatively, instead of a metal-containing gas, a semiconductor gas containing any one or more semiconductor materials (semiconductor elements) such as Si, B, Ge, and Se can be supplied as a precursor gas (film-forming gas) to the processing container 1, thereby forming a semiconductor film (not shown) containing a semiconductor material (semiconductor element) different from the first metal element on the upper surface of the unexposed portion 322 and the unreacted layer 321b. That is, in step S202, either a metal-containing gas containing a second metal element or a semiconductor gas containing semiconductor materials can be supplied. Therefore, a structure in which a semiconductor film (not shown) containing semiconductor materials (semiconductor elements) can be selectively formed on the upper surface of the unexposed portion 322 and the unreacted layer 321b can be formed. Alternatively, in step S202, it may be supplied with both a metal-containing gas containing a second metal element and a semiconductor gas containing semiconductor raw materials.
[0068] <Second Implementation>
[0069] use Figures 9 to 14B An example of the substrate processing method of the second embodiment will be described. Figure 9 This is a flowchart illustrating an example of the substrate processing method of the second embodiment. Figures 10A to 14B This is an example of a schematic diagram of the substrate used in each step. Furthermore, in Figure 10A , Figure 10B middle, Figure 10B This is a schematic diagram of the substrate viewed from above. Figure 10A It is along Figure 10B A schematic diagram of the cross-section of line AA cut off. Similarly, in Figure 11A , Figure 11B middle, Figure 11B This is a schematic diagram of the substrate viewed from above. Figure 11A It is along Figure 11B A schematic diagram of the cross-section of line AA cut off. Figure 12A , Figure 12B middle, Figure 12B This is a schematic diagram of the substrate viewed from above. Figure 12A It is along Figure 12B A schematic diagram of the cross-section of line AA cut off. Figure 13A , Figure 13B middle, Figure 13B This is a schematic diagram of the substrate viewed from above. Figure 13A It is along Figure 13B A schematic diagram of the cross-section of line AA cut off. Figure 14A , Figure 14B middle, Figure 14B This is a schematic diagram of the substrate viewed from above. Figure 14A It is along Figure 14B A schematic diagram of the cross-section of line AA cut off. Additionally, Figure 10B , 11B Although diagrams 12B, 13B, and 14B are viewed from above, the labels and annotations for each component are different. Figure 10A , 11A The same shaded lines are used to illustrate the sections 12A, 13A, and 14A.
[0070] In step S301, a substrate is prepared. Here, the prepared substrate includes a base film 310 (see reference). Figure 2 The base film 310 is disposed on the photoresist film 320 described later (see reference). Figure 2 The film below the substrate 310. Additionally, the substrate 310 is a metal oxide film 330 capable of forming a pattern with openings 335 described later (see reference). Figure 14A , Figure 14B The substrate film 310 is a film whose opening pattern is transferred through etching, serving as a mask. The substrate film 310 can be, for example, a silicon-containing film (e.g., SOG (Spin On Glass) film) or a carbon-containing film (e.g., SOC (Spin On Carbon) film). Alternatively, the substrate film 310 can also be a laminated film obtained by stacking multiple films such as silicon-containing films and carbon-containing films. Furthermore, the substrate film 310, as a laminated film, can also have a BARC (Bottom Anti-Reflective Coating) or similar film. The substrate film 310 can, for example, be a film that can be used as a hard mask.
[0071] In step S302, a photoresist film 320 is formed on the substrate. Figure 2 This is an example of a schematic diagram of a substrate after the formation of the photoresist film 320.
[0072] Here, a photoresist film 320 is formed on the base film 310. The photoresist film 320 is a film containing a metal oxide comprising a first metal element. Alternatively, the photoresist film 320 can be a metal oxide photoresist containing a first metal element, or a resin photoresist (chemically amplified photoresist (CAR)) using a metal oxide containing a first metal element as a sensitizer, but is not limited to these. Here, the first metal element includes any one or more of Sn, W, Te, Zn, Zr, Sb, In, etc. The metal oxide can be, for example, SnO. x (x is any number), WOx (x is any number), TeO x (x is any number), ZnO x (x is any number), ZrO x (x is any number), SbO x (x is any number), InO x (x is any number) etc. Furthermore, during the exposure process described later (refer to S103), the valence or oxidation number of the first metal element changes when the photoresist film 320 is exposed to EUV (Extreme Ultraviolet). Additionally, the photoresist film 320 is a negative photoresist film.
[0073] In step S303, the substrate is exposed. Figure 10A , Figure 10B This is an example of a schematic diagram of a substrate after exposure processing.
[0074] Here, under a nitrogen atmosphere, EUV is applied to the photoresist film 320 of the substrate through a photomask (not shown) with a predetermined pattern. Thus, as... Figure 10A , Figure 10B As shown, an exposed portion 321 irradiated with EUV and an unexposed portion 322 not irradiated with EUV are formed in the photoresist film 320. Here, as Figure 10A , Figure 10B As shown, the photoresist film 320 has a reaction layer 321a (fully exposed area) formed on the central side of the exposure area 321, and an unreacted layer 321b (intermediate exposure area) formed on the outer periphery of the exposure area 321. The reaction layer 321a is the area that is fully exposed to EUV, and the valence or oxidation number of the first metal element changes due to EUV. The unreacted layer 321b is the area where EUV exposure is insufficient, and the first metal element whose valence or oxidation number has not changed remains in a portion. Furthermore, in the unexposed area 322, no EUV exposure is performed, and the first metal element whose valence or oxidation number has not changed remains.
[0075] In step S304, the substrate is subjected to a development process. Figure 11A , Figure 11B This is an example of a schematic diagram of a substrate after development.
[0076] Here, by developing, a portion of the unexposed portion 322 and the unreacted layer 322b of the photoresist film 320 are selectively removed. The developing process can utilize at least one of wet or dry processing. Thus, as... Figure 11A , Figure 11B As shown, photoresist film 320 (reference) Figure 2 The photoresist film 320B is formed with a pattern of openings 325. In addition, the sidewalls of the openings 325 of the photoresist film 320B are formed by a retention portion (residual portion) containing an unreacted layer 322b.
[0077] In step S305, a process is performed to selectively form a metal oxide film 330 from the sidewall of the opening 325 of the photoresist film 320B.
[0078] First, a process is performed to selectively form a metal oxide film 330 on the sidewall of the opening 325 of the photoresist film 320B. Figure 12A , Figure 12B This is an example of a schematic diagram of a substrate after selectively forming a metal oxide film 330. Here, through... Figure 8 The process shown allows for the selective formation of a metal oxide film 330 on the exposed surface (sidewall of opening 325) of the unreacted layer 321b (intermediate exposed portion) relative to the exposed surface (top) of the fully exposed layer 321a (fully exposed portion).
[0079] Next, a process is performed to grow a metal oxide film 330 on the sidewall of the opening 325 of the photoresist film 320B. Figure 13A , Figure 13B This is an example of a schematic diagram of a substrate after the metal oxide film 330 has grown. Here, the metal oxide film 330 is grown using ALD (Atomic Layer Deposition) by alternately supplying a metal-containing gas and a reactive gas (oxidizing gas) to the substrate, embedding the metal oxide film 330 into the opening 325 of the photoresist film 320B. Alternatively, the metal oxide film 330 can be selectively grown laterally, starting from the metal oxide film 330 formed on the sidewall of the opening 325 in step S305. Furthermore, the method of embedding the metal oxide film 330 into the opening 325 of the photoresist film 320B is not limited to this; for example, a fluidized film can be used to embed the film from the bottom of the opening 325.
[0080] Furthermore, the metal-containing gas can be the same gas supplied in step S202. Additionally, the metal contained in the metal-containing gas can be any one 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. Furthermore, the oxidizing gas can be any one of water vapor, oxygen, and ozone.
[0081] In step S306, a resist etching process is performed. Figure 14A , Figure 14B This is an example of a schematic diagram of a substrate after resist etching.
[0082] Here, the photoresist film 320B is removed by etching. This forms a metal oxide film 330 with openings 335. The etching gas can be H2, HF, HCl, HBr, HI, F2, Cl2, Br2, I2, BCl3, CH4, or C. x -H y C x -Cl y C x -Br y Organic acids (carboxylic acid gases, etc.), halogenated silanes (Si-Cl) x Si-H x -Cl y Any one of the following (where x and y are arbitrary numbers).
[0083] As mentioned above, according to Figure 9 The substrate processing method shown can form a metal oxide film 330 on the substrate, such that the exposed portion in the exposure process (S303) is an opening 335, as a mask. That is, a mask with a positive pattern (metal oxide film 330 with opening 335) can be formed on the substrate.
[0084] In addition, the above explains Figure 7 The substrate processing apparatus shown is an example of an apparatus for selective film deposition processing (S104, S305), but it is not limited to this. It could also be used in... Figure 7 The substrate processing apparatus shown can perform selective film formation (S104, S305), as well as any one or more of development (S304) and etching (S105, S106, S306).
[0085] Alternatively, the substrate processing apparatus may be composed of different devices for selective film formation (S104, S305), development (S304), and etching (S105, S106, S306), and these devices may be connected by the same transport device.
[0086] The substrate processing method of this embodiment has been described above, but the present invention is not limited to the above embodiments, etc. Various modifications and improvements can be made within the scope of the spirit of the present invention as described in the claims.
[0087] In addition, this application claims priority based on Japanese Patent Application No. 2024-002841, filed on January 11, 2024, and incorporates the entire contents of that Japanese Patent Application by reference.
[0088] Explanation of reference numerals in the attached figures
[0089] 310 Base film, 320, 320B Photoresist film, 320A Mask, 321 Exposure area, 321a Reaction layer, 321b Layer containing unreacted material, 322 Unexposed area, 325 Opening, 330 Metal oxide film, 335 Opening.
Claims
1. A substrate processing method, characterized in that, have: The step of preparing a substrate having a photoresist film, wherein the photoresist film comprises a metal oxide containing a first metal element; The step of performing an exposure process on the substrate to form an exposed portion and an unexposed portion in the photoresist film; The steps are: supplying a metal-containing gas containing a second metal element different from the first metal element to the substrate, and forming a metal oxide film containing the second metal element on the exposed surface of the unexposed portion; and The step of removing the exposed portion of the photoresist film using the metal oxide film as a mask.
2. The substrate processing method according to claim 1, characterized in that: In the exposure process, extreme ultraviolet light is used for exposure, forming the exposed portion and the unexposed portion in the photoresist film. The exposure section has: The reaction layer is the region where the valence or oxidation number of the first metal element changes due to the extreme ultraviolet light; and The unreacted layer is a region in which the first metal element retains its valence or oxidation number without change.
3. The substrate processing method according to claim 2, characterized in that: In the step of forming the metal oxide film, the first metal element, whose valence or oxidation number does not change in the unexposed portion and the unreacted layer, 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 layer.
4. A substrate processing method, characterized in that, have: The step of preparing a substrate having a photoresist film, wherein the photoresist film comprises a metal oxide containing a first metal element; The step of performing exposure and development treatments on the substrate to form an opening pattern in the photoresist film; The steps of supplying a metal-containing gas containing a second metal element different from the first metal element to the substrate, and forming a metal oxide film containing the second metal element from the sidewall of the opening of the photoresist film; and The step of removing the photoresist film.
5. The substrate processing method according to claim 4, characterized in that: In the exposure process, extreme ultraviolet light is used for exposure, forming exposed and unexposed areas in the photoresist film. The exposure section has: The reaction layer is the region where the valence or oxidation number of the first metal element changes due to the extreme ultraviolet light; and The unreacted layer is a region in which the first metal element retains its valence or oxidation number without change.
6. The substrate processing method according to claim 5, characterized in that: In the development process, the unexposed portion and a portion of the unreacted layer are removed.
7. The substrate processing method according to claim 6, characterized in that: In the step of forming the metal oxide film, the first metal element, whose valence or oxidation number does not change in the unreacted layer, is used as a catalyst to form the metal oxide film containing the second metal element on the exposed surface of the unreacted layer.
8. The substrate processing method according to claim 3 or 7, characterized in that: After the step of forming the metal oxide film, there is also a step of supplying an inert gas to the substrate.
9. The substrate processing method according to claim 7, characterized in that: The step of forming the metal oxide film includes: The steps of supplying a metal-containing gas containing the second metal element and forming a metal oxide film containing the second metal element on the exposed surface of the unreacted layer; and The step of alternately supplying a metal-containing gas containing the second metal element and an oxidizing gas to grow the metal oxide film.
10. The substrate processing method according to claim 1 or 4, characterized in that: The first metallic element includes any one of Sn, W, Te, Zn, Zr, Sb, and In.
11. The substrate processing method according to claim 1 or 4, characterized in that: The second metallic element includes Al, Ti, Ga, Ru, Hf, and any one of Sn, W, Te, Zn, Zr, Sb, and In, which are included only when not used as the first metallic element.
12. The substrate processing method according to claim 1, characterized in that: Instead of forming a metal oxide film containing the second metal element, the method includes supplying a semiconductor gas containing a semiconductor material to the substrate and forming a semiconductor film containing the semiconductor material, which is different from the first metal element, on the sidewall of the photoresist film.
13. The substrate processing method according to claim 12, characterized in that: The semiconductor material includes any one of Si, B, Ge, and Se.