Substrate processing method and substrate processing system

Abstract

This substrate processing method includes step a) and step b). In step a), a silicon-containing film is formed on a first surface of a glass substrate and on a second surface that is the back surface of the first surface. In step b), the silicon-containing film formed on the first surface is removed.

Description

Substrate processing method and substrate processing system

[0001] Various aspects and embodiments of the present disclosure relate to substrate processing methods and systems.

[0002] For example, Patent Document 1 listed below discloses that "When a plurality of cut thin glass substrates are combined to be used as a light guide plate, the cut thin glass substrates are typically stacked and used as the light guide plate. The light guide is applied to display devices such as head-mounted displays, for example."

[0003] Japanese Patent Application Laid-Open No. 2022-36174

[0004] The present disclosure provides a substrate processing method and a substrate processing system capable of performing processes such as film formation and etching on a glass substrate.

[0005] One aspect of the present disclosure is a substrate processing method including steps a) and b). In step a), a silicon-containing film is formed on a first surface of a glass substrate and a second surface opposite to the first surface. In step b), the silicon-containing film formed on the first surface is removed.

[0006] According to various aspects and embodiments of the present disclosure, it is possible to perform processes such as film formation and etching on a glass substrate by overcoming one or more problems resulting from the fact that the processing target is a glass substrate.

[0007] FIG. 1 is a system configuration diagram illustrating an example of a substrate processing system according to an embodiment of the present disclosure. FIG. 2 is a schematic cross-sectional view illustrating an example of the configuration of a film forming apparatus. FIG. 3 is a view illustrating an example of the structure of a boat. FIG. 4 is an enlarged cross-sectional view illustrating an example of the vicinity of a claw portion of a boat. FIG. 5 is a schematic cross-sectional view illustrating an example of an etching apparatus. FIG. 6 is a plan view illustrating an example of a processing apparatus group. FIG. 7 is a diagram for explaining an example of a sensing method. FIG. 8 is a flowchart illustrating an example of a substrate processing method according to a first embodiment. FIG. 9A is a diagram illustrating an example of a process for processing a glass substrate. FIG. 9B is a diagram illustrating an example of a process for processing a glass substrate. FIG. 9C is a diagram illustrating an example of a process for processing a glass substrate. FIG. 10 is a diagram illustrating an example of transmittance for each combination of film thickness and light wavelength when the protective film is polysilicon. FIG. 11 is a diagram illustrating an example of transmittance for each combination of film thickness and light wavelength when the protective film is amorphous silicon. FIG. 12 is a flowchart illustrating an example of a substrate processing method according to a second embodiment. FIG. 13A is a diagram illustrating an example of a process for processing a glass substrate. FIG. 13B is a diagram illustrating an example of a process for processing a glass substrate. Fig. 13C is a diagram showing an example of a process for processing a glass substrate. Fig. 13D is a diagram showing an example of a process for processing a glass substrate. Fig. 13E is a diagram showing an example of a process for processing a glass substrate. Fig. 13F is a diagram showing an example of a process for processing a glass substrate.

[0008] Hereinafter, embodiments of the disclosed substrate processing method and substrate processing system will be described in detail with reference to the drawings. Note that the disclosed substrate processing method and substrate processing system are not limited to the following embodiments.

[0009] In recent years, microfabrication techniques using glass substrates have been used to manufacture high-performance optical elements such as augmented reality (AR) glasses, etc. In the microfabrication, processes such as etching and film formation are performed on the glass substrate.

[0010] In addition, commercially available glass substrates may have metal elements used in the manufacturing process attached to their surfaces. Therefore, when commercially available glass substrates are used as they are in a processing apparatus for etching, film formation, or other processes, components in the processing apparatus that come into contact with the glass substrate may be contaminated with the metal elements. If the components in the processing apparatus are contaminated with the metal elements, the metal elements may be mixed into the glass substrate during the etching or film formation process, which may result in defects in the optical element.

[0011] The present disclosure has an aspect that metal contamination in a processing apparatus due to glass substrates can be suppressed.

[0012] 1 is a system configuration diagram illustrating an example of a substrate processing system 10 according to an embodiment of the present disclosure. The substrate processing system 10 according to this embodiment includes a control device 20, a film forming device 30, an etching device 40, and a processing device group 50.

[0013] The film forming apparatus 30 forms a protective film on both surfaces and side surfaces of the glass substrate W, thereby covering both surfaces and side surfaces of the glass substrate W. In this embodiment, the protective film is a silicon-containing film such as polysilicon or amorphous silicon.

[0014] The etching apparatus 40 removes a protective film covering a surface (hereinafter referred to as a first surface) on which processing such as film formation and etching is performed, of a glass substrate W covered with the protective film. The etching apparatus 40 is an example of a removal apparatus.

[0015] The processing device group 50 includes processing devices that perform processing such as film formation and etching on the glass substrate W. The processing devices perform processing such as film formation and etching on the first surface of the glass substrate W from which the protective film has been removed.

[0016] The control device 20 has a memory, a processor, and an input / output interface. Data such as recipes and programs are stored in the memory. The memory may be, for example, a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), or a solid state drive (SSD). The processor may be a central processing unit (CPU) or a digital signal processor (DSP). The processor executes a program read from the memory to control each part of the film forming device 30, the etching device 40, and the processing device group 50 via the input / output interface based on data such as recipes stored in the memory.

[0017] [Configuration of Film Forming Apparatus 30] Fig. 2 is a schematic cross-sectional view showing an example of the configuration of the film forming apparatus 30. Fig. 2 shows a batch-type vertical heat treatment apparatus as an example of the film forming apparatus 30. Note that the film forming apparatus 30 may be a single-wafer type film forming apparatus as long as it is an apparatus capable of forming a silicon-containing film on both surfaces and side surfaces of a glass substrate.

[0018] The film forming apparatus 30 includes a substantially cylindrical reaction tube 32 whose longitudinal direction extends vertically. The reaction tube 32 has a double-tube structure including an inner tube 33 and an outer tube 34 with a ceiling that covers the inner tube 33 and is spaced apart from the inner tube 33. The inner tube 33 and the outer tube 34 are made of a material with excellent heat resistance and corrosion resistance, such as quartz.

[0019] A manifold 35 made of stainless steel (SUS) or the like and having a cylindrical shape is disposed below the outer pipe 34. The manifold 35 is airtightly connected to the lower end of the outer pipe 34. The inner pipe 33 protrudes from the inner wall of the manifold 35 and is supported by a support ring 36 formed integrally with the manifold 35.

[0020] A lid 37 is disposed below the manifold 35. The lid 37 is configured to be movable up and down by a boat elevator 38. When the lid 37 is raised by the boat elevator 38, the lower side (furnace opening portion) of the manifold 35 is closed. When the lid 37 is lowered by the boat elevator 38, the lower side (furnace opening portion) of the manifold 35 is opened.

[0021] A boat 39 made of, for example, quartz is placed on the lid 37. The boat 39 is configured to accommodate a plurality of glass substrates W at predetermined intervals along the extension direction of the reaction tube 32. FIG. 3 is a diagram showing an example of the structure of the boat 39.

[0022] 3 , for example, the boat 39 includes a top plate 391 and a bottom plate 392. A plurality of support columns 393 (three in the example of FIG. 3 ) are provided between the top plate 391 and the bottom plate 392. Auxiliary columns 394 are provided between the support columns 393. Furthermore, the support columns 393 are provided with claw portions 393 a at predetermined intervals for supporting the glass substrates W. The claw portions 393 a protrude toward the center of the boat 39 and are formed to have surfaces that are approximately parallel to the top plate 391 and the bottom plate 392.

[0023] 4 is an enlarged cross-sectional view showing an example of the vicinity of the claw portions 393a of the boat 39. The claw portions 393a support the edge portions of the glass substrate W on the upper surfaces of the claw portions 393a. This allows the protective film 60 to be formed on the first surface W1 of the glass substrate W, the second surface W2 behind the first surface W1, and the side surface W3 of the glass substrate W. The first surface W1 of the glass substrate W is the surface on which optical elements are formed.

[0024] 2 , a heat insulator 311 is provided around the reaction tube 32 so as to surround the reaction tube 32. A heater 312, such as a resistance heating element, is provided on the inner wall surface of the heat insulator 311. The heater 312 heats the inside of the reaction tube 32 to a predetermined temperature, and the glass substrate W is heated to the predetermined temperature.

[0025] A pipe 313 for introducing a plurality of process gases is connected to a side surface of the manifold 35. Specifically, the pipe 313 is connected to a side surface of the manifold 35 below the support ring 36 (below the inner tube 33). The pipe 313 supplies the process gas to the space within the reaction tube 32. Although one pipe 313 is depicted in the example of FIG. 2 , the number of pipes 313 may be determined according to the type of process gas to be supplied to the space within the inner tube 33. In this embodiment, in order to form the protective film 60, which is a silicon-containing film, on the surface of the glass substrate W, for example, silane gas is used as the process gas.

[0026] The pipe 313 is connected to a processing gas supply source (not shown) via a mass flow controller (not shown) or the like, so that a predetermined amount of processing gas is supplied from the processing gas supply source through the pipe 313 to the space inside the reaction tube 32.

[0027] An exhaust port 314 for exhausting gas from the space inside the reaction tube 32 is provided on the side of the manifold 35. The exhaust port 314 is provided above the support ring 36 and communicates with the space formed between the inner tube 33 and the outer tube 34 inside the reaction tube 32. An exhaust pipe 316 is airtightly connected to the exhaust port 314. A valve 317 and a vacuum pump 318 are provided to the exhaust pipe 316. The valve 317 adjusts the opening of the exhaust pipe 316 to control the pressure inside the reaction tube 32 to a predetermined pressure. The vacuum pump 318 exhausts gas from the reaction tube 32 through the exhaust pipe 316.

[0028] A pipe 315 for supplying a purge gas is inserted below the exhaust port 314 on the side surface of the manifold 35. A purge gas supply source (not shown) is connected to the pipe 315, and a predetermined amount of purge gas (e.g., nitrogen gas) is supplied from the purge gas supply source through the pipe 315 into the reaction tube 32.

[0029] 5 is a schematic cross-sectional view showing an example of the etching apparatus 40. The etching apparatus 40 includes a chamber 420, a substrate holding mechanism 430, a liquid supply unit 440, and a collection cup 450.

[0030] The chamber 420 accommodates a substrate holding mechanism 430, a liquid supply unit 440, and a collection cup 450. An FFU (Fan Filter Unit) 421 is provided on the ceiling of the chamber 420. The FFU 421 forms a downflow within the chamber 420.

[0031] The FFU 421 is connected to a gas supply source 423 via a valve 422. The FFU 421 discharges gas such as dry air supplied from the gas supply source 423 into the chamber 420.

[0032] The substrate holding mechanism 430 includes a rotary holder 431, a support column 432, and a drive unit 433. The rotary holder 431 is provided approximately in the center of the chamber 420. A holding member 4311 that holds the glass substrate W from the side is provided on the upper surface of the rotary holder 431. The holding member 4311 holds the glass substrate W so that the first surface W1 faces upward. The holding member 4311 also holds the glass substrate W horizontally with the glass substrate W slightly spaced from the upper surface of the rotary holder 431.

[0033] The support column 432 is a member extending in the vertical direction, and has a base end rotatably supported by the drive section 433, and a tip end horizontally supporting the rotation holder 431. The drive section 433 rotates the support column 432 around the vertical axis.

[0034] The substrate holding mechanism 430 rotates the support column 432 using the drive unit 433, thereby rotating the rotary holder 431 supported by the support column 432. This causes the glass substrate W held by the rotary holder 431 to rotate.

[0035] The rotation holding portion 431 is not limited to a type that holds the glass substrate W from the side, but may be a type that holds the glass substrate W by suction from below, such as a vacuum chuck.

[0036] The liquid supply unit 440 supplies various processing liquids to the glass substrate W held by the substrate holding mechanism 430. The liquid supply unit 440 includes a plurality of nozzles 441 a, 441 b (two in the example of FIG. 5 ), an arm 442 that horizontally supports the nozzles 441 a, 441 b, and a swiveling and lifting mechanism 443 that swivels and raises and lowers the arm 442. Note that the nozzle 441 a and the nozzle 441 b may be supported by separate arms.

[0037] An etching liquid supply source 445a is connected to the nozzle 441a via a valve 444a and a flow rate regulator 446a, and a rinsing liquid supply source 445b is connected to the nozzle 441b via a valve 444b and a flow rate regulator 446b.

[0038] The nozzle 441a discharges an etching solution supplied from an etching solution supply source 445a. The etching solution in this embodiment is, for example, TMAH (tetramethylammonium hydroxide), fluoronitric acid, or fluoronitric acid acetic acid.

[0039] The nozzle 441b discharges a rinse liquid supplied from a rinse liquid supply source 445b, such as deionized water (DIW).

[0040] The collection cup 450 is disposed to surround the rotary holder 431, and collects the processing liquid scattered from the glass substrate W by the rotation of the rotary holder 431. A drain port 451 is formed in the bottom of the collection cup 450, and the processing liquid collected by the collection cup 450 is discharged from the drain port 451 to the outside of the etching apparatus 40. In addition, an exhaust port 452 is formed in the bottom of the collection cup 450, through which the gas supplied from the FFU 421 is discharged to the outside of the etching apparatus 40.

[0041] The number of nozzles provided in the etching device 40 is not limited to the above example, and may be, for example, a configuration including a single nozzle that ejects both the etching liquid and the rinse liquid.

[0042] An etching liquid is supplied from the nozzle 441a to the glass substrate W held by the holding member 4311 so that the first surface W1 faces upward, thereby removing the protective film 60 formed on the first surface W1 of the glass substrate W. At this time, the protective film 60 formed on the second surface W2 and the side surface W3 of the glass substrate W remains without being removed.

[0043] [Configuration of Processing Device Group 50] Fig. 6 is a plan view showing an example of the processing device group 50. In Fig. 6, for convenience, the internal components of some of the devices are drawn transparently. The processing device group 50 includes a vacuum transfer chamber 51, a plurality of processing devices 52, a plurality of load lock chambers 53, and an atmospheric transfer chamber 54. The vacuum transfer chamber 51 is an example of a transfer chamber.

[0044] Processing devices 52 are connected to the sidewall of the vacuum transfer chamber 51 via a gate valve G1. In the example of Fig. 6, eight processing devices 52 are connected to the vacuum transfer chamber 51, but the disclosed technology is not limited to this. The number of processing devices 52 connected to the vacuum transfer chamber 51 may be seven or less, or nine or more.

[0045] The glass substrate W from which the protective film 60 formed on the first surface W1 has been removed by the etching device 40 is carried into each processing device 52. Then, each processing device 52 processes the first surface W1 of the glass substrate W by performing processes such as film formation and etching on the first surface W1 of the glass substrate W, thereby processing the first surface W1 of the glass substrate W or forming a structure on the first surface W1 of the glass substrate W.

[0046] A plurality of load lock chambers 53 are connected to the other side wall of the vacuum transfer chamber 51 via gate valves G2. In the example of Fig. 6, two load lock chambers 53 are connected to the vacuum transfer chamber 51, but the disclosed technology is not limited to this. The number of load lock chambers 53 connected to the vacuum transfer chamber 51 may be one, or three or more.

[0047] A transfer device 511 is disposed within the vacuum transfer chamber 51. The transfer device 511 moves within the vacuum transfer chamber 51 along guide rails 510 provided within the vacuum transfer chamber 51. The transfer device 511 transfers the glass substrate W between the processing device 52 and the load lock chamber 53. The interior of the vacuum transfer chamber 51 is maintained at a pressure lower than atmospheric pressure. Note that the transfer device 511 may be configured to be fixed at a predetermined position within the vacuum transfer chamber 51 and not move within the vacuum transfer chamber 51.

[0048] One side wall of the load lock chamber 53 is connected to the vacuum transfer chamber 51 via a gate valve G2, and the other side wall is connected to the atmospheric transfer chamber 54 via a gate valve G3. A plurality of load ports 55 are provided on a side wall of the atmospheric transfer chamber 54 other than the side wall on which the gate valve G3 is provided. Each load port 55 is connected to a container such as a FOUP (Front Opening Unified Pod) that can accommodate a plurality of glass substrates W. The atmospheric transfer chamber 54 may be provided with an aligner module or the like that changes the orientation of the glass substrates W.

[0049] The pressure inside the atmospheric transfer chamber 54 is atmospheric pressure. A transfer device 541 is provided inside the atmospheric transfer chamber 54. The transfer device 541 moves inside the atmospheric transfer chamber 54 along a guide rail 540 provided inside the atmospheric transfer chamber 54, and transfers the glass substrate W between the load lock chamber 53 and a container connected to the load port 55. Note that the transfer device 541 may be configured to be fixed at a predetermined position inside the atmospheric transfer chamber 54 and not move inside the atmospheric transfer chamber 54.

[0050] Sensors 56 for detecting the position of the glass substrate W are provided near the gate valves G1, G2, G3, and the load port 55. The sensor 56 has a light-emitting unit 56a and a light-receiving unit 56b, as shown in FIG. 7 , for example. The light-emitting unit 56a emits visible light, such as red light, toward the light-receiving unit 56b. The light-receiving unit 56b outputs a signal indicating whether or not it has received the light emitted from the light-emitting unit 56a to the control device 20. The control device 20 detects the position of the glass substrate W based on whether or not the light emitted from the light-emitting unit 56a is blocked by the glass substrate W.

[0051] In this embodiment, the glass substrate W transmits light, making it difficult for the sensor 56 to detect the position of the glass substrate W. However, in this embodiment, a protective film 60 is formed on the surface of the glass substrate W. Depending on the thickness of the protective film 60, the protective film 60 may block the light emitted from the light-emitting unit 56 a, allowing the sensor 56 to detect the position of the glass substrate W. However, if the protective film 60 is too thick, deformation of the glass substrate W, such as warping, may occur due to the difference in stress between the glass substrate W and the protective film 60. When the thickness of the glass substrate W is approximately 700 μm, a protective film thickness of, for example, 600 nm or more may cause the glass substrate W to warp. Warping of the glass substrate W may reduce the accuracy of the position and shape of holes and trenches when the glass substrate W is processed by the processing device 52. Therefore, it is preferable not to form the protective film 60 too thick on the glass substrate W. However, if the protective film 60 is too thin, the light emitted from the light-emitting unit 56 a may pass through the protective film 60.

[0052] In this embodiment, the protective film 60 is also formed on the side surface W3 of the glass substrate W. Furthermore, as shown in FIG. 7 , the light-emitting portion 56 a emits light toward the protective film 60 formed on the side surface W3 of the glass substrate W in a direction along the side surface W3 (thickness direction of the glass substrate W). Because the glass substrate W has a thickness of 700 μm or more, the protective film 60 formed on the side surface W3 has a thickness of 700 μm or more in the direction along the side surface W3. This allows the protective film 60 formed on the side surface W3 to block the light emitted from the light-emitting portion 56 a, even if the protective film 60 is not formed very thick on the second surface W2 of the glass substrate W. This allows the sensor 56 to detect the position of the glass substrate W while preventing deformation of the glass substrate W.

[0053] [Substrate Processing Method] Fig. 8 is a flowchart showing an example of a substrate processing method according to Embodiment 1. The process illustrated in Fig. 8 is realized by the control device 20 controlling each part of the film forming device 30, the etching device 40, and the processing device group 50.

[0054] First, a protective film 60 is formed on the glass substrate W (step S10). Step S10 is an example of process a). In step S10, as shown in FIG. 9A , for example, the protective film 60, which is a silicon-containing film, is formed on the first surface W1, the second surface W2, and the side surface W3 of the glass substrate W. In this embodiment, the protective film 60 is formed by the film forming apparatus 30, and therefore the protective film 60 is simultaneously formed on the first surface W1, the second surface W2, and the side surface W3 of the glass substrate W. In step S10, the glass substrate W is covered with the protective film 60 having a thickness of 40 nm or more and 600 nm or less.

[0055] Here, commercially available glass substrates W may have metal elements and the like attached to their surfaces that were used during the manufacturing process. Therefore, when a commercially available glass substrate W is directly used in the processing device 52 for etching, film formation, or other processes, the members inside the chamber of the processing device 52 that come into contact with the glass substrate W may be contaminated with the metal elements. If the members inside the chamber are contaminated with the metal elements, the metal elements may be mixed in during the etching or film formation process on the glass substrate W, which may result in defects in the optical element.

[0056] In contrast, in this embodiment, in step S10, the glass substrate W is covered with the protective film 60 having a thickness of 40 nm or more. This makes it possible to prevent the components in the chamber of the processing device 52 that come into contact with the glass substrate W from being contaminated with metal elements in the subsequent etching and film formation processes on the glass substrate W.

[0057] In step S10, the thickness of the protective film 60 formed on the glass substrate W is controlled to, for example, 600 nm or less, thereby making it possible to suppress deformation of the glass substrate W.

[0058] Next, the protective film 60 formed on the first surface W1 of the glass substrate W is removed (step S11). Step S11 is an example of process b). In step S11, as shown in FIG. 9B , for example, the protective film 60 formed on the first surface W1 of the glass substrate W is removed by the etching device 40, thereby exposing the first surface W1.

[0059] In step S11, the second surface W2 and the side surface W3 remain covered with the protective film 60. This makes it possible to prevent components inside the chamber of the processing device 52 that come into contact with the glass substrate W (e.g., a stage on which the glass substrate W is placed) from being contaminated with metal elements. Furthermore, the protective film 60 formed on at least one of the second surface W2 and the side surface W3 can block the light emitted from the light emitting unit 56a, making it possible to detect the position of the glass substrate W.

[0060] Next, processing of the glass substrate W is performed (step S12). Step S12 is an example of process c). In step S12, as shown in Fig. 9C, for example, processing such as etching and film formation is performed on the glass substrate W by the processing device 52 of the processing device group 50, and a structure 61 is formed on the first surface W1 of the glass substrate W. Then, the processing shown in this flowchart ends.

[0061] The first embodiment has been described above. As described above, the substrate processing method in the first embodiment includes steps a) and b). In step a), a silicon-containing film (protective film 60) is formed on a first surface (first surface W1) of a glass substrate (glass substrate W) and a second surface (second surface W2) opposite to the first surface. In step b), the silicon-containing film formed on the first surface is removed. This makes it possible to suppress metal contamination by the glass substrate.

[0062] In the first embodiment, in step a), the silicon-containing film formed on the first and second surfaces of the glass substrate has a thickness of 40 nm or more, which can prevent metal elements adhering to the surface of the glass substrate from scattering.

[0063] In the first embodiment, in step a), the thickness of the silicon-containing film formed on the first surface and the second surface of the glass substrate is preferably 600 nm or less, thereby suppressing warping of the glass substrate.

[0064] In the first embodiment described above, the silicon-containing film is formed of amorphous silicon or polysilicon, which allows the surface of the glass substrate W to be easily covered with the protective film 60 and allows the protective film 60 to be easily removed in the removal step.

[0065] In the first embodiment described above, in step a), the silicon-containing film is also formed on the side surface (side surface W3) of the glass substrate W. This allows the sensor 56 to detect the position of the glass substrate W.

[0066] The first embodiment described above is a substrate processing system 10 that includes a film formation apparatus (film formation apparatus 30), a removal apparatus (etching apparatus 40), and a processing apparatus (processing apparatus 52). The film formation apparatus forms a silicon-containing film on a first surface of a glass substrate and a second surface, which is the surface opposite to the first surface, and the removal apparatus removes the silicon-containing film formed on the first surface of the glass substrate. The processing apparatus performs at least one of film formation and etching on the first surface of the glass substrate from which the silicon-containing film has been removed. This makes it possible to suppress metal contamination by the glass substrate.

[0067] In the first embodiment described above, the substrate processing system further includes a transfer chamber (vacuum transfer chamber 51) for transferring glass substrates to and from the processing apparatus. The transfer chamber includes a transfer device (transfer device 511) for transferring the glass substrate and a sensor (56) for detecting the position of the glass substrate. The film forming apparatus further forms a silicon-containing film on the side surface of the glass substrate. The sensor detects the position of the glass substrate based on whether or not light is blocked by the silicon-containing film formed on the side surface of the glass substrate. This allows the sensor 56 to detect the position of the glass substrate W.

[0068] Second Embodiment In the first embodiment, after the glass substrate W is covered with the protective film 60, the protective film 60 is removed from the first surface W1 on which the optical elements are to be formed, and the optical elements are formed on the first surface W1 from which the protective film 60 has been removed. In contrast, in the second embodiment, after the glass substrate W is covered with the protective film 60, the protective film 60 formed on the first surface W1 on which the optical elements are to be formed is processed, thereby forming optical elements that include a portion of the protective film 60 formed on the first surface W1. The following description will focus on differences from the first embodiment.

[0069] [Substrate Processing Method] Fig. 12 is a flowchart showing an example of a substrate processing method according to Embodiment 2. The process illustrated in Fig. 12 is realized by the control device 20 controlling each part of the film forming device 30, the etching device 40, and the processing device group 50.

[0070] First, a protective film 60 is formed on the glass substrate W (step S20). Step S20 is an example of process c). In step S20, as shown in FIG. 9A , for example, the protective film 60, which is a silicon-containing film, is formed on the first surface W1, the second surface W2, and the side surface W3 of the glass substrate W. In this embodiment, the protective film 60 is formed by the film formation apparatus 30, and therefore the protective film 60 is simultaneously formed on the first surface W1, the second surface W2, and the side surface W3 of the glass substrate W.

[0071] Next, a silicon oxide film is formed (step S21). In step S21, the glass substrate W covered with the protective film 60 is carried into a film forming apparatus in the processing apparatus group 50. Then, a silane-containing gas such as monosilane gas is introduced as a source gas into the film forming apparatus, and an oxygen-containing gas such as oxygen gas or ozone gas is introduced as a reactive gas. As a result, a silicon oxide film 70 is formed on the protective film 60 formed on the first surface W1 of the glass substrate W, as shown in FIG. 13A , for example.

[0072] The silicon oxide film 70 may be formed by a method other than the CVD (Chemical Vapor Deposition) method, such as the PVD (Physical Vapor Deposition) method, the ALD (Atomic Layer Deposition) method, or spin coating.

[0073] Furthermore, in step S20, if the thickness of the protective film 60 formed on the first surface W1 is less than the thickness necessary for forming the optical element, a step of forming an additional protective film 60 on the protective film 60 formed on the first surface W1 may be performed between steps S20 and S21. The step of forming an additional protective film 60 on the protective film 60 formed on the first surface W1 is an example of step e).

[0074] Furthermore, in step S20, if the thickness of the protective film 60 formed on the first surface W1 is greater than the thickness necessary for forming the optical element, an etching step for reducing the thickness of the protective film 60 formed on the first surface W1 may be performed between steps S20 and S21. The etching step for reducing the thickness of the protective film 60 formed on the first surface W1 is an example of step f).

[0075] Furthermore, if the thickness of the protective film 60 formed on the first surface W1 in step S20 is less than the thickness necessary for forming the optical element, an additional protective film 60 is formed on the protective film 60 formed on the first surface W1 between steps S20 and S21. The thickness of the formed protective film 60 may then be fine-tuned by etching the protective film 60 until the thickness of the protective film 60 reaches the thickness necessary for forming the optical element.

[0076] Next, a hard mask is formed (step S22). In step S22, the glass substrate W on which the silicon oxide film 70 has been formed is carried into a coating device in the processing device group 50. Then, a processing liquid for hard mask formation is applied onto the silicon oxide film 70 by the coating device, and a hard mask 71 including a spin-on carbon film 71 a and a spin-on glass film 71 b is formed on the silicon oxide film 70, as shown in FIG. 13B , for example.

[0077] 13B, the hard mask 71 includes two layers, a spin-on carbon film 71a and a spin-on glass film 71b, but the hard mask 71 may include only one of the spin-on carbon film 71a or the spin-on glass film 71b. The hard mask 71 may also include a metal-containing film, a silicon oxynitride film, a back surface antireflection film, or the like.

[0078] Next, a resist film is formed (step S23). In step S23, for example, in a coating device, a processing liquid for forming a resist film is applied onto the hard mask 71, thereby forming a resist film on the hard mask 71. Then, the glass substrate W on which the resist film has been formed is carried into an exposure device in the processing device group 50, and a predetermined pattern is exposed onto the resist film. Then, the glass substrate W on which the predetermined pattern has been exposed onto the resist film is carried into a developing device in the processing device group 50, and developed. As a result, a resist film 72 of a predetermined pattern is formed on the hard mask 71, as shown in FIG. 13C , for example.

[0079] The resist film 72 is, for example, a photoresist film for EUV (Extreme Ultraviolet). The patterning of the resist film may be performed by, for example, placing a patterned mold (mask) on the resist film and curing the resin resist film by irradiating it with ultraviolet light or by heat treatment through the mold. The patterning of the resist film may also be performed by nanoimprint lithography.

[0080] Next, the hard mask 71 and the silicon oxide film 70 are etched (step S24). In step S24, the glass substrate W on which the resist film 72 of a predetermined pattern has been formed is carried into an etching device in the processing device group 50. Then, an etching gas such as a fluorine-containing gas is introduced into the etching device, and the hard mask 71 is etched using the resist film 72 as a mask. As a result, a pattern corresponding to the resist film 72 is transferred to the hard mask 71, as shown in FIG. 13D , for example.

[0081] Then, an etching gas such as a fluorine-containing gas is introduced into the etching apparatus, and the silicon oxide film 70 is etched using the hard mask 71 onto which the pattern of the resist film 72 is transferred as a mask. As a result, the pattern corresponding to the hard mask 71 is transferred to the silicon oxide film 70, as shown in Fig. 13E, for example. The etching of the silicon oxide film 70 is continued until the protective film 60 is exposed from the bottom of the opening 70a in the silicon oxide film 70.

[0082] Next, the protective film 60 is etched (step S25). In step S25, an etching gas such as a fluorine-containing gas is introduced into an etching apparatus, and the protective film 60 formed on the first surface W1 is etched using the silicon oxide film 70 to which the pattern of the hard mask 71 has been transferred as a mask. As a result, a pattern 60p of the protective film 60 corresponding to the pattern of the hard mask 71 is formed, as shown in FIG. 13F, for example. The etching of the protective film 60 is performed until the first surface W1 of the glass substrate W is exposed from the bottom of the opening 60pi of the protective film 60. Steps S21 to S25 are an example of process d).

[0083] The second embodiment has been described above. As described above, the substrate processing method in the second embodiment includes steps c) and d). In step c), a silicon-containing film is formed on a first surface of a glass substrate and a second surface, which is the surface opposite to the first surface. In step d), a pattern is formed in the silicon-containing film formed on the first surface. This makes it possible to suppress metal contamination by the glass substrate when forming a pattern in the silicon-containing film formed on the first surface.

[0084] The substrate processing method according to the second embodiment may also include step e). Step e) is performed before step d), and involves forming a silicon-containing film on the silicon-containing film formed on the first surface so as to increase the thickness of the silicon-containing film formed on the first surface. This allows the formation of an optical element including protective film 60 of a desired thickness.

[0085] The substrate processing method according to the second embodiment may also include step f). Step f) is performed before step d), and involves etching the silicon-containing film formed on the first surface to reduce its thickness. This allows the formation of an optical element including protective film 60 of a desired thickness.

[0086] The second embodiment described above is a substrate processing system 10 including a film formation apparatus (film formation apparatus 30) and a processing apparatus (processing apparatus group 50). The film formation apparatus forms a silicon-containing film on a first surface of a glass substrate and a second surface, which is the surface opposite to the first surface. The processing apparatus performs at least one of film formation and etching on the silicon-containing film formed on the first surface, thereby forming a pattern in the silicon-containing film formed on the first surface. This makes it possible to suppress metal contamination by the glass substrate when forming a pattern in the silicon-containing film formed on the first surface.

[0087] [Others] The technology disclosed in the present application is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist thereof.

[0088] For example, in each of the above-described embodiments, the position of the glass substrate W is detected based on whether the light emitted from the light-emitting portion 56a is blocked by the protective film 60 formed on the side surface W3 of the glass substrate W, but the disclosed technology is not limited to this. For example, the protective film 60 may be formed thick on the second surface W2 of the glass substrate W within a range of 600 nm or less. This makes it possible to detect the position of the glass substrate W based on whether the light emitted from the light-emitting portion 56a is blocked by the protective film 60 formed on the second surface W2. This makes it possible to more easily detect the position of the glass substrate W.

[0089] From the viewpoint of reducing the time required to form the protective film 60 and preventing warping of the glass substrate W, it is preferable that the protective film 60 is thin. However, if the protective film 60 is too thin, the transmittance of the light emitted from the light-emitting unit 56a may exceed 50%, depending on the material of the protective film 60. If the transmittance of the light emitted from the light-emitting unit 56a is 50% or less, it is possible to detect the position of the glass substrate W by setting a threshold value.

[0090] When the protective film 60 is made of polysilicon, the transmittance (%) for each combination of the thickness of the protective film 60 and the wavelength of light is, for example, as shown in Figure 10. The example in Figure 10 shows the wavelength of red light (625 to 660 nm), which is a visible light that is often used in sensors.

[0091] 10, when the thickness of the protective film 60 is in the range of 20 to 200 nm and 300 to 600 nm, the transmittance for light of either wavelength is below 50%. Therefore, when the protective film 60 is made of polysilicon, the thickness is preferably in the range of 20 to 200 nm and 300 to 600 nm.

[0092] When the protective film 60 is made of amorphous silicon, the transmittance (%) for each combination of the thickness of the protective film 60 and the wavelength of light is as shown in, for example, Figure 11. Referring to Figure 11, the transmittance for light of any wavelength between 625 and 660 nm is below 50% for the entire thickness range of 40 to 600 nm. Therefore, when the protective film 60 is made of amorphous silicon, the position of the glass substrate W can be detected if the thickness is between 40 and 600 nm.

[0093] Furthermore, since the glass substrate W is an insulator, it cannot be attracted to an electrostatic chuck by electrostatic force. However, depending on the thickness of the protective film 60, which is a silicon-containing film, it is possible to attract the glass substrate W on which the protective film 60 is formed to an electrostatic chuck. For example, when the protective film 60 is formed on the second surface W2 of the glass substrate W with a thickness of 500 nm or more, the glass substrate W can be attracted to an electrostatic chuck. This makes it possible to attract the glass substrate W to an electrostatic chuck without having to separately form a conductive film on the glass substrate W.

[0094] Furthermore, the protective film 60, which is a silicon-containing film, may be doped with impurities other than silicon. Examples of impurities that may be doped into the protective film 60 include phosphorus, boron, arsenic, antimony, aluminum, and gallium. Depending on the type of impurity, the conductivity of the protective film 60 can be increased, so that even if the protective film 60 is thinner, the glass substrate W can be attracted to the electrostatic chuck.

[0095] It should be noted that the disclosed embodiments are illustrative in all respects and should not be considered limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

[0096] Furthermore, the following supplementary notes are disclosed regarding the above-described embodiments.

[0097] (Supplementary Note 1) A substrate processing method comprising: a) forming a silicon-containing film on a first surface of a glass substrate and on a second surface that is a surface opposite to the first surface; and b) removing the silicon-containing film formed on the first surface. (Supplementary Note 2) The substrate processing method according to Supplementary Note 1, wherein in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 40 nm or more. (Supplementary Note 3) The substrate processing method according to Supplementary Note 1 or 2, wherein in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 600 nm or less. (Supplementary Note 4) The substrate processing method according to any one of Supplements 1 to 3, wherein the silicon-containing film is formed of amorphous silicon, polysilicon, or silicon doped with at least one of phosphorus and boron. (Supplementary Note 5) The substrate processing method according to Supplementary Note 4, wherein the silicon-containing film is formed of polysilicon, and in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 20 nm to 200 nm, or 300 nm to 600 nm. (Supplementary Note 6) The substrate processing method according to Supplementary Note 4, wherein the silicon-containing film is formed of amorphous silicon, and in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 20 nm to 600 nm. (Supplementary Note 7) The substrate processing method according to any one of Supplements 1 to 6, wherein in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 500 nm or more. (Supplementary Note 8) The substrate processing method according to any one of Supplements 1 to 7, wherein in step a), the silicon-containing film is also formed on side surfaces of the glass substrate. (Supplementary Note 9) A substrate processing system comprising: a film formation device that forms a silicon-containing film on a first surface of a glass substrate and a second surface that is the backside of the first surface; a removal device that removes the silicon-containing film formed on the first surface of the glass substrate; and a processing device that performs at least one of film formation and etching on the first surface of the glass substrate from which the silicon-containing film has been removed.(Supplementary Note 10) The substrate processing system according to Supplementary Note 9, further comprising: a transfer chamber for transferring the glass substrate into and out of the processing apparatus, the transfer chamber having: a transfer device for transferring the glass substrate; and a sensor for detecting a position of the glass substrate, the film formation apparatus further forming the silicon-containing film on a side surface of the glass substrate, and the sensor detecting the position of the glass substrate based on whether light is blocked by the silicon-containing film formed on at least one of a second surface and a side surface of the glass substrate. (Supplementary Note 11) A substrate processing method comprising: c) steps of forming a silicon-containing film on a first surface of the glass substrate and a second surface that is a reverse surface of the first surface; and d) steps of forming a pattern in the silicon-containing film formed on the first surface. (Supplementary Note 12) The substrate processing method according to Supplementary Note 11, further comprising: e) a step, performed before step d), of forming an additional silicon-containing film on the silicon-containing film formed on the first surface so as to increase a thickness of the silicon-containing film formed on the first surface. (Supplementary Note 13) The substrate processing method according to Supplementary Note 11 or 12, further comprising: f) a step, performed before step d), of etching the silicon-containing film formed on the first surface so as to reduce a thickness of the silicon-containing film formed on the first surface. (Supplementary Note 14) The substrate processing method according to any one of Supplements 11 to 13, wherein in step c), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 40 nm or more. (Supplementary Note 15) The substrate processing method according to any one of Supplements 11 to 14, wherein in step c), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 600 nm or less. (Supplementary Note 16) The substrate processing method according to any one of Supplements 11 to 15, wherein the silicon-containing film is formed of amorphous silicon, polysilicon, or silicon doped with at least one of phosphorus and boron. (Supplementary Note 17) The substrate processing method according to Supplementary Note 16, wherein the silicon-containing film is formed of polysilicon, and in the step c), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 20 nm or more and 200 nm or less, or 300 nm or more and 600 nm or less.(Supplementary Note 18) The substrate processing method according to Supplementary Note 16, wherein the silicon-containing film is formed of amorphous silicon, and wherein in step c), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 20 nm or more and 600 nm or less. (Supplementary Note 19) The substrate processing method according to any one of Supplements 11 to 18, wherein in step c), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 500 nm or more. (Supplementary Note 20) The substrate processing method according to any one of Supplements 11 to 19, wherein in step c), the silicon-containing film is also formed on a side surface of the glass substrate. (Supplementary Note 21) A substrate processing system comprising: a film formation apparatus that forms a silicon-containing film on a first surface and a second surface that is a backside of the first surface of a glass substrate; and a processing apparatus that performs at least one of film formation and etching on the silicon-containing film formed on the first surface to form a pattern in the silicon-containing film formed on the first surface. (Appendix 22) The substrate processing system according to Appendix 21, further comprising a transfer chamber for transferring the glass substrate to and from the processing device, the transfer chamber having a transfer device for transferring the glass substrate and a sensor for detecting a position of the glass substrate, the film forming device further forming the silicon-containing film on a side surface of the glass substrate, and the sensor detecting the position of the glass substrate based on whether light is blocked by the silicon-containing film formed on at least one of the second surface and the side surface of the glass substrate.

[0098] G: Gate valve W: Glass substrate W1: First surface W2: Second surface W3: Side surface 10: Substrate processing system 20: Control device 30: Film forming device 40: Etching device 50: Processing device group 60: Protective film 70: Silicon oxide film 71: Hard mask 72: Resist film

Claims

1. A substrate processing method comprising: a) forming a silicon-containing film on a first surface of a glass substrate and on a second surface that is a reverse surface of the first surface; and b) removing the silicon-containing film formed on the first surface.

2. The substrate processing method according to claim 1, wherein in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 40 nm or more.

3. The substrate processing method according to claim 1 or 2, wherein in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 600 nm or less.

4. The substrate processing method according to claim 1 or 2, wherein the silicon-containing film is formed of amorphous silicon, polysilicon, or silicon doped with at least one of phosphorus and boron.

5. The substrate processing method according to claim 4, wherein the silicon-containing film is formed of polysilicon, and in step a), the thickness of the silicon-containing film formed on the first surface and the second surface of the glass substrate is 20 nm or more and 200 nm or less, or 300 nm or more and 600 nm or less.

6. The substrate processing method according to claim 4, wherein the silicon-containing film is formed of amorphous silicon, and in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 20 nm or more and 600 nm or less.

7. The substrate processing method according to claim 1 or 2, wherein in step a), the silicon-containing film formed on the first surface and the second surface of the glass substrate has a thickness of 500 nm or more.

8. The substrate processing method according to claim 1 or 2, wherein in the step a), the silicon-containing film is also formed on a side surface of the glass substrate.

9. A substrate processing system comprising: a film forming device that forms a silicon-containing film on a first surface of a glass substrate and a second surface that is the reverse side of the first surface; a removal device that removes the silicon-containing film formed on the first surface of the glass substrate; and a processing device that performs at least one of film forming and etching processes on the first surface of the glass substrate from which the silicon-containing film has been removed.

10. The substrate processing system of claim 9, further comprising a transfer chamber for transferring the glass substrate to and from the processing apparatus, the transfer chamber having a transfer device for transferring the glass substrate and a sensor for detecting a position of the glass substrate, the film forming apparatus further forming the silicon-containing film on a side surface of the glass substrate, and the sensor detecting the position of the glass substrate based on whether or not light is blocked by the silicon-containing film formed on at least one of the second surface and the side surface of the glass substrate.

11. A substrate processing method comprising: c) a step of forming a silicon-containing film on a first surface of a glass substrate and a second surface that is a reverse surface of the first surface; and d) a step of forming a pattern in the silicon-containing film formed on the first surface.

12. The substrate processing method of claim 11, further comprising: e) a step performed before step d) of forming a further silicon-containing film on the silicon-containing film formed on the first surface so as to increase a thickness of the silicon-containing film formed on the first surface.

13. The substrate processing method according to claim 11 or 12, further comprising: f) a step performed before step d) of etching the silicon-containing film formed on the first surface to reduce a thickness of the silicon-containing film formed on the first surface.

14. A substrate processing system comprising: a film formation device that forms a silicon-containing film on a first surface of a glass substrate and a second surface that is the reverse side of the first surface; and a processing device that forms a pattern in the silicon-containing film formed on the first surface by performing at least one of film formation and etching on the silicon-containing film formed on the first surface.

15. The substrate processing system of claim 14, further comprising a transfer chamber for transferring the glass substrate to and from the processing apparatus, the transfer chamber having a transfer device for transferring the glass substrate and a sensor for detecting a position of the glass substrate, the film forming apparatus further forming the silicon-containing film on a side surface of the glass substrate, and the sensor detecting the position of the glass substrate based on whether or not light is blocked by the silicon-containing film formed on at least one of the second surface and the side surface of the glass substrate.