Substrate processing apparatus, substrate processing method, and chemical filter

Abstract

The invention provides a substrate processing apparatus, a substrate processing method, and a chemical filter. The purpose of the present invention is to perform stable pattern formation on a metal-containing resist film. The substrate processing apparatus according to the present disclosure is used for pattern formation by exposing and developing a metal-containing resist film formed on a substrate, and is characterized in that: a chemical filter is provided in a flow path through which a gas is supplied into the substrate processing apparatus; the chemical filter includes a plurality of filtration units that are arranged toward the downstream side and that respectively remove different substances in the gas, and the plurality of filtration units include an acid filtration unit for removing acidic substances and an alkali filtration unit for removing alkaline substances.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus, a substrate processing method, and a chemical filter. Background Art

[0002] In the manufacturing process of semiconductor devices, various processes are performed by transporting semiconductor wafers (hereinafter referred to as wafers) as substrates within a system. For example, as shown in Patent Document 1, a gas that has passed through a filter and been purified is supplied into the system to keep the atmosphere in which the wafers are transported and processed clean.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-150372 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] The present disclosure provides a technique capable of stably forming a pattern on a metal-containing resist film.

[0008] Solutions to the Problems

[0009] The present disclosure is a substrate processing apparatus for forming a pattern by exposing and developing a metal-containing resist film formed on a substrate, wherein

[0010] a chemical filter is provided in a flow path for supplying a gas into the substrate processing apparatus, and the chemical filter includes a plurality of filter units arranged toward the downstream side and respectively removing different substances in the gas,

[0011] among the plurality of filter units, an acid filter unit for removing acidic substances and a base filter unit for removing basic substances are included.

[0012] Effects of the Invention

[0013] The present disclosure can stably form a pattern on a metal-containing resist film. Brief Description of the Drawings

[0014] Figure 1 is a top view of a wafer processing system to which a chemical filter is applied.

[0015] Figure 2 is a longitudinal sectional front view of the wafer processing system.

[0016] Figure 3 is a schematic diagram of the wafer processing system.

[0017] Figure 4Is a longitudinal sectional side view of the chemical filter of the first embodiment

[0018] Figure 5 Is a schematic diagram illustrating the function of the chemical filter.

[0019] Figure 6 Is a schematic diagram illustrating the function of the chemical filter.

[0020] Figure 7 Is a schematic diagram illustrating the function of the chemical filter.

[0021] Figure 8 Is a schematic diagram illustrating the function of the chemical filter.

[0022] Figure 9 Is a longitudinal sectional side view of the chemical filter of the second embodiment.

[0023] Figure 10 Is a longitudinal sectional side view of the chemical filter of the third embodiment.

[0024] Figure 11 Is a longitudinal sectional side view showing a part of the wafer processing system.

[0025] Figure 12 Is a longitudinal sectional side view showing another structural example of the wafer processing system.

[0026] Figure 13 Is a longitudinal sectional side view of the chemical filter of the fourth embodiment.

[0027] Figure 14 Is a longitudinal sectional side view of another chemical filter of the fourth embodiment.

[0028] Figure 15 Is a longitudinal sectional side view of the chemical filter of the fifth embodiment.

[0029] Figure 16 Is a longitudinal sectional side view of the chemical filter of the sixth embodiment.

[0030] Figure 17 Is a longitudinal sectional side view of the chemical filter of the seventh embodiment.

[0031] Figure 18 Is a longitudinal sectional side view of the chemical filter of the eighth embodiment.

[0032] Figure 19 Is a longitudinal sectional side view showing another structural example of the wafer processing system.

[0033] Figure 20 Is a longitudinal sectional side view showing another structural example of the wafer processing system.

[0034] Figure 21 It is a longitudinal sectional side view showing another structural example of the wafer processing system.

[0035] Figure 22 It is a top view showing still another structural example of the wafer processing system.

[0036] Figure 23 It is a longitudinal sectional front view constituting a cassette transfer station of the wafer processing system.

[0037] Figure 24 It is a cross-sectional top view of the cassette transfer station.

[0038] Figure 25 It is a longitudinal sectional front view constituting an interface station of the wafer processing system.

[0039] Figure 26 It is a longitudinal sectional side view of a cylinder including a chemical filter.

[0040] Explanation of reference numerals

[0041] W, wafer; 1, wafer processing system; 5, chemical filter; 53, acid filtration section; 54, alkali filtration section. Detailed implementation mode

[0042] Hereinafter, a wafer processing system as a substrate processing apparatus according to the present embodiment will be described with reference to the drawings. In addition, in this specification, elements having substantially the same functional structure are denoted by the same reference numerals, and repeated descriptions are thus omitted.

[0043] <Wafer processing system>

[0044] First, the structure of the wafer processing system according to the present embodiment will be described. Figure 1 , Figure 2 They are a schematic top view and a front view schematically showing the structure of the wafer processing system 1, respectively. In the present embodiment, the case where the wafer processing system 1 is a lithography processing system that performs a resist film formation process and a development process on a wafer W as a circular substrate will be described as an example.

[0045] As Figure 1 shown, the wafer processing system 1 has a cassette transfer station 2 that feeds in and out a cassette C containing a plurality of wafers W, and a processing station 3 having a plurality of various processing devices that apply a predetermined process to the wafers W. Moreover, the wafer processing system 1 has a structure in which the cassette transfer station 2, the processing station 3, and the interface station 4 are integrally connected, and the interface station 4 performs the transfer of the wafer W between the processing station 3 and an exposure apparatus (not shown) adjacent to the interface station 4 on the opposite side of the processing station 3. In addition, as Figure 1As shown, two processing stations 3 are provided between the cassette transfer station 2 and the interface station 4. However, the number of processing stations 3 can be one or more than three.

[0046] The cassette transfer station 2 is provided with a plurality of cassette placement plates 21, a wafer transfer device 22, and a wafer transfer device 23. The cassette transfer station 2 transfers wafers between the cassette C placed on the cassette placement plate 21 and the processing station 3 by using the wafer transfer device 22 or the wafer transfer device 23. Therefore, each of the wafer transfer device 22 and the wafer transfer device 23 is provided with a drive mechanism in the X direction, Y direction, up and down direction, and around the vertical axis (θ direction) as needed, and can also be provided with a drive mechanism in all directions.

[0047] At least one of the wafer transfer device 22 and the wafer transfer device 23 can perform the transfer of wafers between the cassette C, and can also perform the wafer transfer operation with the processing station 3. In addition, the wafer transfer operation with the processing station 3 refers to, for example, performing the wafer transfer with the third module G3 having a transfer device to which the wafer transfer device 33 in the processing station 3 described later can travel. The third module G3 can be provided with a plurality of transfer devices (not shown) arranged in the up and down direction.

[0048] In addition, an inspection device (not shown) for inspecting the wafer W can be provided at a position where either the wafer transfer device 22 or the wafer transfer device 23 can travel.

[0049] The processing station 3 is provided with a plurality of modules. For example, three modules, namely, the first module G1, the second module G2, and the fourth module G4, are provided. In addition, as Figure 2 shown, a plurality of layers 31 each having the first module G1 and the second module G2 are stacked in the up and down direction. For example, the first module G1 is provided on the front side ( Figure 1 the negative X direction side) of the processing station 3, and the second module G2 is provided on the back side ( Figure 1 the positive X direction side) of the processing station 3. The fourth module G4 is provided on the interface station 4 side ( Figure 1 the positive Y direction side) of the processing station 3 or at a portion connected to another adjacent processing station 3. The fourth module G4 can be provided with a plurality of transfer devices arranged in the up and down direction. In addition, the above-mentioned third module G3 can be provided in the processing station 3.

[0050] A plurality of processing devices are arranged in the first module G1. For example, a film forming device for pattern formation and a developing processing device (both not shown) are arranged. The film forming device for pattern formation can include, for example, an anti-reflection film forming device in addition to a resist film forming device.

[0051] For example, the plurality of processing devices are arranged and configured in the horizontal direction. In addition, the number, configuration, and type of these processing devices can be arbitrarily selected.

[0052] In these pattern-forming film-forming apparatuses and developing apparatuses, for example, processing is performed by supplying a predetermined processing liquid or a predetermined gas onto the wafer W. Thereby, in the pattern-forming film-forming apparatus, formation of a resist film used as a mask when forming a film on the lower layer side, formation of an antireflection film for efficiently performing light irradiation processing such as exposure processing, and the like are performed. On the other hand, in the developing apparatus, a concavo-convex shape serving as the above-described mask is formed by locally removing the exposed resist film.

[0053] For example, in the second module G2, a heat treatment apparatus (not shown) that performs heat treatment such as heating and cooling of the wafer W is provided along the vertical direction and the horizontal direction. In addition, in the second module G2, although not shown, a hydrophobization treatment apparatus that performs hydrophobization treatment to improve the fixing property between the resist liquid and the wafer W and a peripheral exposure apparatus that exposes the outer peripheral portion of the wafer W are provided along the vertical direction ( Figure 2 the Z direction) and the horizontal direction. The number and arrangement of these heat treatment apparatuses, hydrophobization treatment apparatuses, and peripheral exposure apparatuses can also be arbitrarily selected.

[0054] As Figure 1 shown, a wafer transfer region 32 is formed in a region that is sandwiched between the first module G1 and the second module G2 in a plan view. For example, a wafer transfer apparatus 33 is disposed in the wafer transfer region 32.

[0055] The wafer transfer apparatus 33 has a transfer arm 33a that is movable in the Y direction, the front-rear direction, the θ direction, and the vertical direction, for example. The wafer transfer apparatus 33 moves within the wafer transfer region 32 and can transfer the wafer W to a predetermined apparatus within the surrounding first module G1, second module G2, third module G3, and fourth module G4. In the case of having a plurality of processing stations 3 as Figure 1 shown, the wafer transfer apparatus 33 provided in the processing station 3 located on the interface station 4 side can transfer the wafer W not only to the first module G1, second module G2, and fourth module G4 but also to a predetermined apparatus within a fifth module G5 described later.

[0056] For example, as Figure 2As shown, a plurality of wafer transfer devices 33 are arranged vertically. One wafer transfer device 33 can transfer the wafer W to a specified device at the height of the upper plurality of layers 31 among the plurality of vertically stacked layers 31. For the specified device at the height of the plurality of layers 31 located below these layers 31, other wafer transfer devices 33 can transfer the wafer W. A plurality of wafer transfer areas 32 are provided to enable such transfer of the wafer W. In addition, the number of wafer transfer devices 33 and the number of layers 31 corresponding to one wafer transfer device 33 can be arbitrarily selected, such as providing a wafer transfer device 33 for each layer 31, etc.

[0057] In addition, a shuttle transfer device (not shown) may be provided in the wafer transfer area 32 or the first module G1 and the second module G2. The shuttle transfer device linearly transfers the wafer W between the space adjacent to the processing station 3 on one side and another space adjacent to it on the opposite side.

[0058] At the interface station 4, there are provided a fifth module G5 having a plurality of transfer devices, a wafer transfer device 41, and a wafer transfer device 42. The interface station 4 uses the wafer transfer device 41 or the wafer transfer device 42 to transfer the wafer W between the fifth module G5 that performs the transfer of the wafer W using the wafer transfer device 33 and the exposure machine. For this purpose, the wafer transfer device 41 and the wafer transfer device 42 each have a drive mechanism in directions such as the X direction, the Y direction, the vertical direction, and the direction around the vertical axis (θ direction) as needed, and may also have a drive mechanism in all directions. At least any one of the wafer transfer device 41 and the wafer transfer device 42 can support the wafer W and transfer it between the transfer device in the fifth module G5 and the exposure device.

[0059] The cleaning processing device for cleaning the surface of the wafer W and the above-mentioned peripheral exposure device can be provided at a position accessible by any one of the wafer transfer device 41 and the wafer transfer device 42 within the interface station 4.

[0060] As described above, the inspection device can be provided at the cassette transfer station 2, but can also be provided at the processing station 3 and the interface station 4, at a position accessible by any one of the transfer arms ( Figure 1 or Figure 2 the wafer transfer devices 33, 41, 42) provided inside them.

[0061] In the above-described wafer processing system 1, a control device 100 is provided. The control device 100 is, for example, a computer, and has one or more control circuits and a program storage unit (not shown) to execute processing based on a program. A program for controlling the processing of the wafer W in the wafer processing system 1 is stored in the program storage unit. In addition, a program for controlling the operation of the drive systems of the various processing devices, transfer devices, etc. described above to implement the wafer processing in the wafer processing system 1 is also stored in the program storage unit. Further, the above program can be stored in a computer-readable storage medium H and loaded from the storage medium H into the control device 100. Commands (each step) are incorporated in the program to output control signals to each part of the wafer processing system 1 according to the loaded program, and through the control signals, control the transfer of the substrate by each wafer transfer device and the operation of each processing device.

[0062] <Operation of Wafer Processing System>

[0063] The wafer processing system 1 is configured as described above. Next, an example of wafer processing performed using the wafer processing system 1 configured as described above will be described.

[0064] First, a cassette C containing a plurality of wafers W is sent into the cassette transfer station 2 of the wafer processing system 1 and placed on the cassette mounting plate 21. Next, each wafer W in the cassette C is sequentially taken out by the wafer transfer device 22 or the wafer transfer device 23 and transferred to the transfer device of the third module G3.

[0065] The wafer W transferred to the transfer device of the third module G3 is supported by the wafer transfer device 33 and transferred to the hydrophobic treatment device provided in the second module G2 for hydrophobic treatment. Next, it is transferred to the resist film forming device by the wafer transfer device 33, a resist film is formed on the wafer W, and after being transferred to the heat treatment device and subjected to pre-baking treatment, it is transferred to the transfer device of the fifth module G5. In addition, in the case of having a plurality of processing stations 3 as shown in Figure 1 , Figure 2 , the wafer W is temporarily placed on the transfer device of the fourth module G4 before being transferred to the transfer device of the fifth module G5, and then transferred between the plurality of wafer transfer devices 33. In addition, the wafer W can also be transferred to the peripheral exposure device by the wafer transfer device 33 as needed for exposure treatment of the peripheral portion of the wafer.

[0066] The wafer W transferred to the transfer device of the fifth module G5 is transferred to the exposure device by the wafer transfer device 41 and the wafer transfer device 42 and subjected to exposure treatment with a specified pattern. In addition, the wafer W can be cleaned by the cleaning treatment device before the exposure treatment.

[0067] The exposed wafer W is transported to the transfer device of the fifth module G5 by the wafer transfer device 41 and the wafer transfer device 42. Then, it is transported to the heat treatment device by the wafer transfer device 33 for post-exposure baking treatment.

[0068] The wafer W after post-exposure baking treatment is transported to the development processing device by the wafer transfer device 33 for development. After the development is completed, the wafer W is transported to the heat treatment device by the wafer transfer device 33 for hard-bake treatment.

[0069] Then, the wafer W is transported to the transfer device of the third module G3 by the wafer transfer device 33 and is transported to the cassette C on the specified cassette mounting plate 21 by the wafer transfer device 22 or the wafer transfer device 23 of the cassette transfer station 2. Thus, a series of lithography processes are completed.

[0070] In addition, the wafer processing system (substrate processing system) of the present disclosure is not limited to the structure and operation described above. For example, in the above-described embodiment, the case of transferring the wafer W between the interface station 4 and the exposure device is described, but it may not be directly connected to the exposure device. In this case, for example, after the wafer W is transported from the cassette transfer station 2 to the processing station 3 and necessary processing is performed, it is transported back to the cassette transfer station 2 to send out the wafer W to the outside. In addition, unnecessary devices among the devices listed as processing devices may not be provided, or processing in these devices may not be performed.

[0071] <Regarding the resist film>

[0072] In the resist film forming device of the wafer processing system 1, a resist film containing a metal resist is formed. More specifically, for example, a film of a metal oxide resist (MOR) is formed. In addition, the above-mentioned metal-containing resist contains metal as a constituent of the resist, and does not refer to a resist containing metal only as an impurity. The metal as a constituent of this resist is, for example, tin (Sn). Moreover, the resist film of this MOR is developed after being exposed to light of an appropriate wavelength such as EUV (Extreme Ultra Violet) in an exposure device, thereby forming a pattern (pattern formation). Unless otherwise specified in the following description, the resist film is a resist film of MOR.

[0073] The wafer processing system 1 is disposed in the atmospheric atmosphere in a clean room of a semiconductor manufacturing factory. In order to suppress the scattering of fine particles inside the system, the wafer processing system 1 sucks in the atmosphere around the system and supplies the atmosphere in a specified direction to form an air flow. However, the MOR resist film is denatured by reacting with various components contained in the atmosphere, and the line width (Critical Dimension: CD) of the formed resist pattern changes. In addition, in the evaluation test described later, as an example of the component that causes the CD change, an acidic substance is shown, and more specifically, acetic acid is shown.

[0074] The wafer processing system 1 is equipped with a chemical filter that removes chemical substances in the gas. As described above, the atmosphere sucked into the wafer processing system 1 forms an air flow inside the system after passing through this chemical filter. Since this chemical filter is composed of a plurality of filter parts that target different substances for removal, various chemical substances that can cause a change in the CD of the resist pattern can be removed from the atmosphere supplied into the wafer processing system 1. Therefore, it is possible to perform such a stable pattern formation process on each wafer W: suppressing the variation in CD between wafers W in the same lot and preventing the CD from deviating from the allowable range.

[0075] <Example of the configuration of the chemical filter>

[0076] Refer to Figure 3 The schematic front view of the wafer processing system 1 in [] is described. The cassette transfer station 2, the processing station 3, and the interface station 4 each include a housing 20, 30, 40, and the spaces inside the housings 20, 30, 40 are configured to be separated from each other. In such separated spaces, the above-described transfer path for the wafer W and various devices for processing and placing the wafer W are provided, and the wafer W is transferred between the stations 2 to 4 via openings (not shown) formed in the housings 20 to 40.

[0077] A fan 51 is provided above each of the housings 20, 30, 40. In addition, a flow path 52 leading downward from the fan 51 is provided in each of the housings 20, 30, 40, and a chemical filter 5 is provided at the downstream end of the flow path 52 and at the top of the housing. In addition, the reference numeral 52A in the figure is a flow path forming member for forming the flow path 52. By the action of the fan 51, the atmosphere is sucked into the flow path 52 from the outside of the wafer processing system 1, and then the atmosphere goes to the downstream side in the flow path 52. By such a flow, the atmosphere is supplied from above to the chemical filter 5 and passes through the chemical filter 5, and is discharged from below the chemical filter 5. The atmosphere that has passed through the chemical filter 5 and thus removed various chemical substances forms a downward air flow inside the housing.

[0078] <Example of the structure of the chemical filter>

[0079] Figure 4is a longitudinal sectional side view of the chemical filter 5. In addition, the Figure 4 Arrows in the figures showing the structure of the chemical filter described later indicate the flow direction of the gas passing through the chemical filter. The chemical filter 5 includes an acid filtration section 53 for removing acidic substances, a base filtration section 54 for removing basic substances, and an organic filtration section 55 for removing organic substances. The acid filtration section 53, the base filtration section 54, and the organic filtration section 55 are stacked in this order toward the upstream side of the flow path 52. In this example, the thicknesses (sizes in the gas flow direction) of the acid filtration section 53, the base filtration section 54, and the organic filtration section 55 are the same as each other.

[0080] Regarding these acid filtration section 53, base filtration section 54, and organic filtration section 55, they are sometimes collectively referred to as filtration sections 53 to 55. In addition, in this example, since the flow path 52 is formed in the Z direction (vertical direction), the stacking direction of the filtration sections 53 to 55 is also the Z direction.

[0081] The filtration sections 53 to 55 will be described in further detail. These filtration sections 53 to 55 are filter materials having a removing effect on the above-mentioned respective substances. The organic filtration section 55 is composed of, for example, activated carbon, and can adsorb and remove various organic substances such as hydrocarbons, alcohols, ketones, esters, and aromatic compounds. The base filtration section 54 is composed of, for example, an ion exchanger, and can remove various amines and ammonia as the above-mentioned basic substances. The ion exchanger is, for example, a strongly acidic cation exchanger having a sulfonic acid group as a functional group. The acid filtration section 53 is composed of, for example, an ion exchanger, and can remove various organic acids such as acetic acid and various inorganic acids such as hydrochloric acid, hydrofluoric acid, nitric acid, and sulfuric acid as the above-mentioned acidic substances. The ion exchanger is, for example, a strongly basic anion exchanger having a quaternary ammonium group as a functional group.

[0082] For example, each of the filtration sections 53 to 55 is configured as a plate-like body, and is configured to have a structure in which many small holes communicate from one main surface of the plate to the other main surface, so that the supplied gas can pass through. If a specific example of this structure is cited, an example of a honeycomb structure can be cited. As described above, regarding the acid filtration section 53 and the base filtration section 54 as ion exchangers, for example, an ion exchange resin can be used to have such a structure.

[0083] In addition, instead of having such a structure, the filtration sections 53 to 55 can also be formed into a plate shape (including a thin sheet shape) by making a fiber containing a component for removing the above-mentioned chemical substances into a textile, a knitted fabric, or a non-woven fabric. In this case, the above-mentioned small holes are gaps formed between the fibers. When using fibers in this way, the acid filtration section 53 and the base filtration section 54 can be made of ion exchange fibers to form an ion exchanger. The organic filtration section 55 can be composed of activated carbon fibers.

[0084] <Effect of Chemical Filter>

[0085] As described above, in the chemical filter 5, an organic filter section 55, an alkali filter section 54, and an acid filter section 53 are provided on the downstream side. Thus, by having respective filter sections for different removal targets, the atmosphere that has passed through the chemical filter 5 is supplied to the transfer path of the wafer W in the wafer processing system 1 and each device that processes and places the wafer W in a state where various chemical substances that cause fluctuations in the CD of the pattern formed on the resist film have been removed. Therefore, as described above, stabilization of the CD of the pattern of the resist film can be achieved.

[0086] In addition, in the film forming apparatus for pattern formation, EBR (Edge Bead Removal) for supplying an organic solvent to the peripheral portion of the wafer W after film formation to remove unwanted portions, pre-wetting treatment for supplying an organic solvent to the wafer W before film formation to improve the wettability with respect to the processing liquid for forming the film, etc. are performed. This organic solvent may contain, for example, PGMEA (Propylene glycol monomethyl ether acetate). Considering that a small amount of PGMEA leaks to the outside of the wafer processing system 1, it is supplied to the chemical filter 5 by the fan 51.

[0087] Refer to Figures 5 - 8 Describe the function of the chemical filter 5 in the case where PGMEA is supplied as an organic substance in this way. In Figures 5 - 8 , PGMEA in the atmosphere is denoted as 61. For a period of time after a new chemical filter 5 is installed in the wafer processing system 1, the PGMEA 61 supplied to the chemical filter 5 is collected by the organic filter section 55 of the filter section set as the most upstream side in the chemical filter 5 and is not released from the chemical filter 5 ( Figure 5 ).

[0088] However, when the supply of this PGMEA 61 or other organic substances to the chemical filter 5 continues and the collection amount in the organic filter section 55 becomes large, the adsorption and removal performance of the organic filter section 55 for newly supplied organic substances deteriorates and this performance falls below the allowable range. That is, the organic filter section 55 reaches the end of its life ( Figure 6 ). Then, the PGMEA 61 supplied to the chemical filter 5 passes through the organic filter section 55 and is supplied to the alkali filter section 54. By the action of the alkali filter section 54, the PGMEA 61 decomposes and acetic acid (denoted as 62 in the figure) is generated ( Figure 7 ). As described above, acetic acid 62 causes fluctuations in the CD of the pattern of the resist film as MOR. However, since an acid filter section 53 is provided on the downstream side of the alkali filter section 54 where acetic acid 62 is generated in this way, acetic acid 62 is removed by the action of this acid filter section 53 ( Figure 8) and prevent acetic acid 62 from being released from the chemical filter 5.

[0089] To further illustrate the Figures 5 - 8 function of the chemical filter 5 shown, the chemical filter 5 includes filter parts 53 to 55. Thus, as described above, various chemical substances can be removed, and therefore, it is advantageous for suppressing the CD variation of the resist pattern. However, when the height of the space where the chemical filter 5 is provided is limited, since it has a structure with filter parts as various filter materials, the thickness of each of the filter parts 53 to 55 is relatively small. Since the length of the life of the filter parts 53 to 55 corresponds to the thickness, it is difficult to extend the life of each of the filter parts 53 to 55.

[0090] Therefore, when the concentration of organic substances around the wafer processing system 1 is relatively high, as Figure 5 、 Figure 6 shown, the organic filter part 55 reaches the end of its life relatively early, and acetic acid 62 is generated from PGMEA 61, which becomes the main cause of the CD variation of the resist pattern. However, in the chemical filter 5, the alkali filter part 54 and the acid filter part 53 are arranged in sequence toward the downstream side on the downstream side of the organic filter part 55. Therefore, as Figure 7 、 Figure 8 explained, acetic acid 62 is prevented from being released from the chemical filter 5.

[0091] Therefore, even if the wafer processing system 1 is placed in an environment where the life of the organic filter part 55 is relatively short due to the relatively high concentration of organic substances around the wafer processing system 1, it is not necessary to replace the chemical filter 5 before the end of its life. That is to say, according to the structure of the chemical filter 5, when it is provided in the wafer processing system 1, the replacement frequency is prevented from increasing. This reduces the frequency of the state where the conveyance and processing of the wafer W in the wafer processing system 1 are stopped for this replacement, and thus suppresses the reduction in the productivity of the wafer processing system 1.

[0092] <Second Embodiment of the Chemical Filter>

[0093] Hereinafter, other examples of the chemical filter provided in the wafer processing system 1 instead of the chemical filter 5 will be described. Figure 9It is a longitudinal sectional side view of the chemical filter 5A of the second embodiment. The chemical filter 5A is not provided with an organic filter portion 55, and is composed of an alkali filter portion 54 and an acid filter portion 53 that are stacked on each other. The arrangement order of the alkali filter portion 54 and the acid filter portion 53 is the same as that of the chemical filter 5. The acid filter portion 53 is located on the downstream side of the flow path 52 with respect to the alkali filter portion 54, so that acetic acid 62 generated in the alkali filter portion 54 can be removed by the acid filter portion 53. As described in the description of the chemical filter 5, in the wafer processing system 1, the lower side of the flow path 52 provided with the chemical filter is the downstream side. Therefore, the acid filter portion 53 is arranged below the alkali filter portion 54.

[0094] As described above, the chemical filter 5A is not provided with an organic filter portion 55. Therefore, when the chemical filter 5 or the chemical filter 5A is selectively provided in the space at a specified height in the flow path 52, the thickness of the acid filter portion 53 and / or the thickness of the alkali filter portion 54 can be made larger for the chemical filter 5A. In addition, for the Figure 9 chemical filter 5A shown, the thickness is the same as that of the Figure 4 chemical filter 5 shown, and for the thicknesses of the acid filter portion 53 and the alkali filter portion 54 respectively, the thickness of the chemical filter 5A is greater than the thickness of the chemical filter 5. Subsequently, an example of the relationship between the thicknesses of the filter portions between the chemical filters will be further described.

[0095] <Chemical Filter Third Embodiment>

[0096] Figure 10 It is a longitudinal sectional side view of the chemical filter 5B of the third embodiment. The chemical filter 5B is composed of stacking an acid filter portion 53, an alkali filter portion 54, and an organic filter portion 55 in the same manner as the chemical filter 5. The acid filter portion 53, the organic filter portion 55, and the alkali filter portion 54 are arranged in sequence toward the downstream side of the flow path 52.

[0097] Moreover, in the chemical filter 5B, the thickness of the organic filter portion 55 is greater than the thicknesses of the acid filter portion 53 and the alkali filter portion 54. By setting the thickness in this way, the period from the start of using the chemical filter 5B until the organic filter portion 55 reaches the end of its life becomes longer. During this long period, even if PGMEA 61 is supplied to the chemical filter 5B, it will not reach the alkali filter portion 54. Therefore, the generation of acetic acid 62 in the alkali filter portion 54 and the release of the acetic acid 62 from the chemical filter 5B can be prevented. Thus, like the chemical filter 5, this chemical filter 5B can also suppress the replacement frequency even when used in an environment with a relatively high organic matter concentration.

[0098] In addition, assuming that an organic substance other than PGMEA or a compound generated by a reaction such as decomposition of the organic substance affects the CD of the resist pattern, if the thickness of the organic filter section 55 is large as in the chemical filter 5B, the organic substance can be collected for a long time. That is, when an organic substance other than PGMEA causes a change in the CD of the resist pattern, the structure of the chemical filter 5B having the above-described relationship according to the thickness relationship of the filter sections 53 to 55 can also suppress the replacement frequency of the chemical filter 5B, and thus is preferable. In addition, for Figure 4 the chemical filter 5 described in

[0099] <Other Examples of Chemical Filter Configuration>

[0100] For each chemical filter, it is shown as being disposed in the flow path 52 through which the atmosphere forming the downward air flow passes, but the arrangement is not limited to this. In Figure 11 an example is shown in which the chemical filter 5 is provided in the flow path 71 provided on the side wall of the cassette transfer station 2. Using the fan 72, the atmosphere sucked from the outside of the wafer processing system 1 flows laterally in the flow path 71 and passes through the chemical filter 5, and an air flow is formed in the lateral direction within the housing 20. Accordingly, the filter sections 53 to 55 are arranged laterally. As shown in this Figure 11 example, the system structure is not limited to the one in which gas is supplied to the chemical filter from above, and the installation orientation of the chemical filter and the supply direction of the gas passing through the chemical filter can be arbitrarily set. In other stations other than the cassette transfer station 2, the chemical filter may also be provided so that the gas flowing laterally within the housing passes through it.

[0101] In addition, Figure 12 an example is shown in which a gas supply system 73 is connected to the wafer processing system 1. The gas supply system 73 is a system provided outside the wafer processing system 1 and includes a supply mechanism 74 that supplies gas whose temperature and humidity are adjusted to be controlled within a specified range. The gas supply system 73 and the processing device 70 provided at the processing station 3 are connected via a pipe 75. In the gas supply system 73, the chemical filter 5 is disposed in the flow path 76 provided on the upstream side of the pipe 75, and the gas supplied from the supply mechanism 74 passes through the chemical filter 5 and is supplied to the processing station 3 via the pipe 75.

[0102] The gas whose temperature and humidity are adjusted in this way is an inert gas such as nitrogen. Moreover, the processing apparatus 70 to which this inert gas is supplied includes a housing 77, and a processing space for processing the wafer W is formed inside the housing 77, and this inert gas is supplied to this processing space. Therefore, this processing space is a space formed by the housing 77 inside the housing 30 of the processing station 3 and partitioned from the wafer transfer area 32 where the atmosphere is supplied from the chemical filter 5 at the top. Examples of the processing apparatus 70 include a pattern forming film forming apparatus and a heating apparatus.

[0103] In addition, the inert gas supplied from the gas supply system 73 via the chemical filter 5 is not limited to the processing apparatus for the wafer W. For example, in the processing station 3, a standby apparatus for making a plurality of wafers W standby is provided in a standby space partitioned from the wafer transfer area 32 because it is surrounded by the housing 77. This inert gas may be supplied to this standby space. In addition, as the standby apparatus, it may be provided at a station other than the processing station 3 such as the cassette transfer station 2. Further, as the supply destination of this inert gas, it may also be the cassette mounting plate 21 of the cassette transfer station 2, and the inert gas is supplied to the inside of the cassette C in which the wafer W is standby via an unillustrated gas supply port of the cassette mounting plate 21. The cassette C is a transfer container called a FOUP (Front Opening Unify Pod), and is configured to be able to supply gas from the outside to the inside in this way. As described above, the supply destination of the inert gas from the gas supply system 73 is not limited to the processing station 3.

[0104] In Figure 11 、 Figure 12 an example of using the chemical filter 5 is given, but the chemical filters 5A, 5B, and each chemical filter described later may be used instead of the chemical filter 5. Moreover, for this gas supply system 73, the chemical filters 5A, 5B, and the chemical filter described later may be used instead of the chemical filter 5. In addition, as shown in the example of Figure 12 , the gas supplied to each chemical filter is not limited to the atmosphere, and further, regarding the installation position of the chemical filter, it may be separated from the transfer path of the wafer W and the housing that houses the processing apparatus 70.

[0105] <Another Structural Example of the Chemical Filter>

[0106] Figure 13is a longitudinal sectional side view of the chemical filter 5C of the fourth embodiment. Similar to the chemical filter 5, the chemical filter 5C is configured by arranging an organic filter section 55, an alkali filter section 54, and an acid filter section 53 toward the downstream side of the flow path 52. However, gaps 57 and 58 are respectively formed between the organic filter section 55 and the alkali filter section 54, and between the alkali filter section 54 and the acid filter section 53. Therefore, for the chemical filter 5C, it is configured such that a gap is provided between one filter section and another filter section that is arranged behind the one filter section when observing the flow path 52 toward the downstream side. In addition, reference numeral 59 in the figure is a cylindrical frame that surrounds the side circumferences of the filter sections 53 to 55 and forms the flow path 52, and supports the filter sections 53 to 55 in such a manner as to form the gaps 57 and 58. In Figure 13 the example shown, the gaps 57 and 58 have the same width, but the widths may also be different from each other. In Figure 14 it shows an example where the width of the gap 57 is smaller than the width of the gap 58.

[0107] In this way, the adjacent filter sections of the filter sections 53 to 55 can be configured such that they do not contact each other. However, as described above, the lifespan of the filter section corresponds to the thickness. From the viewpoint of arranging the chemical filter within the limited configuration space of the chemical filter in the system and setting it in such a way that the lifespan of each filter section is longer, it is preferable that the adjacent filter sections contact each other.

[0108] Figure 15 is a side view of the chemical filter 5D of the fifth embodiment. This chemical filter 5D is configured in the same way as the chemical filter 5C, by arranging an organic filter section 55, an alkali filter section 54, and an acid filter section 53 toward the downstream side of the flow path 52. However, since the flow path 52 is formed horizontally, the filter sections 53 to 55 are also arranged horizontally. Moreover, the filter sections 53 to 55 are arranged in the frame 59 with a relatively large separation from each other. It can also be seen Figure 13 、 Figure 14 that the widths of the gaps 57 and 58 described in

[0109] are formed to be larger. Figure 15 As shown in this

[0110] Figure 16 example, the filter sections are not limited to being close to each other, and they can also be separated relatively greatly. In such a case where they are separated relatively greatly, the chemical filter is also constituted by each filter section from the filter section (in this example, the organic filter section 55) arranged on the most upstream side in the flow path to the filter section (in this example, the acid filter section 53) arranged on the most downstream side. Figure 13The chemical filter 5C shown has a substantially identical structure. However, as a difference, protrusions 50 are provided in the alkali filtration section 54 and the acid filtration section 53. The protrusions 50 protrude toward the upstream side and the downstream side of the flow path 52 respectively. By using the protrusions 50, unevenness is formed on the main surfaces of the alkali filtration section 54 and the acid filtration section 53, and the surface area of the main surfaces becomes relatively large, thereby improving the removal performance of chemical substances. In addition, the protrusions 50 are not protrusions that are inevitably formed in the manufacturing process of the filtration section, and their height is, for example, 0.5 mm or more.

[0111] In addition, in the chemical filter 5E, when viewed in the gas flow direction, the protrusions 50 formed on the opposite surface 54A of the alkali filtration section 54 facing the acid filtration section 53 and the protrusions 50 formed on the opposite surface 53A of the acid filtration section 53 facing the alkali filtration section 54 do not overlap each other. Therefore, it is possible to prevent the width of the gap 58 between the acid filtration section 53 and the alkali filtration section 54 from being large, and to prevent the chemical filter 5E from becoming large-sized, which is therefore preferable.

[0112] In the chemical filter 5E, the protrusions 50 are not provided in the organic filtration section 55, but the organic filtration section 55 may also be provided with protrusions 50 in the same manner as the alkali filtration section 54 and the acid filtration section 53. In addition, the thickness of the filtration sections 53 to 55 in the case of such a structure with protrusions 50 refers to the thickness of the portion without protrusions 50.

[0113] As shown in the example of the chemical filter 5E, the filtration sections 53 to 55 are not limited to being flat as in the examples of the chemical filters 5, 5A to 5D. Figure 17 , as an example of other chemical filters in which the filtration sections 53 to 55 are not flat, a longitudinal sectional side view of the chemical filter 5F of the seventh embodiment is shown. In the chemical filter 5F, the filtration sections 53 to 55 are each formed into a plate shape that repeats mountain-folded portions and valley-folded portions from one end side toward the other end side, and thus are formed into a wave shape when viewed from the side. In addition, Figure 17 in the example, the filtration sections 53 to 55 have a so-called corrugated shape by having creases, but they may also be formed into a shape that depicts a wave-shaped curve when viewed from the side without creases.

[0114] As described above, by setting the filtration sections 53 to 55 to be wave-shaped when viewed from the side, the surface area on the side facing the upstream side of the flow path 52 is increased, and the removal performance of chemical substances can be improved. In addition, Figure 16 in this example, gaps 57 and 58 are provided between the filtration sections 53 to 55, but a structure in which the gaps 57 and 58 are not provided may also be used.

[0115] Figure 18 is a longitudinal sectional side view of the chemical filter 5G of the seventh embodiment. This chemical filter 5G is the same asFigure 13 The chemical filter 5C is configured in substantially the same manner, except that the gap 57 between the filter units 54 and 55 is not provided.

[0116] Since there are deviations in the supply amount of the organic matter at various locations in the organic filter unit 55, the life of a part of the positions arrives earlier than that of other positions, and PGMEA 61 is supplied from this position to the alkali filter unit 54. That is, PGMEA 61 is locally supplied from a part of the position of the organic filter unit 55 to the alkali filter unit 54. In this case, in the alkali filter unit 54, acetic acid 62 is generated at a local position and is released toward the acid filter unit 53 as shown by the relatively thick arrow in the figure. However, this acetic acid 62 diffuses through the gap 58 between the acid filter unit 53 and the alkali filter unit 54, and the supply to the local position of the acid filter unit 53 is suppressed. That is, by providing the gap 58, it is possible to prevent the local position of the acid filter unit 53 from reaching the end of its life earlier than other positions and being unable to remove acetic acid 62. As a result, the replacement frequency of this chemical filter 5G can be suppressed.

[0117] In addition, for each of the chemical filters described above that are provided with the gap 58 between the alkali filter unit 54 and the acid filter unit 53 in the same manner as this chemical filter 5G, the same effects as those of the chemical filter 5G described above can be obtained. Further, as in Figure 13 the chemical filter 5C, in the case where the gap 57 between the organic filter unit 55 and the alkali filter unit 54 is also provided, PGMEA 61 is also supplied to the alkali filter unit 54 after diffusing through this gap 57. Therefore, it is possible to more reliably suppress the shortening of the life of the local position of the above-described acid filter unit 53, which is preferable.

[0118] <Setting of Different Chemical Filters within the Same System>

[0119] In addition, in each of the chemical filters described above, the same chemical filter may be provided in the wafer processing system 1, or different chemical filters may be provided. It is possible to consider the size of the installation space for the chemical filters at various locations within the system, the concentration of each chemical substance around the installation location, etc., and selectively configure an appropriate chemical filter. More specifically, for each of the chemical filters provided in the flow paths connected to the spaces separated from each other, different structures may be provided. Hereinafter, such an example will be described with reference to the drawings.

[0120] Figure 19 In the example shown in the figure, in the wafer processing system 1, the chemical filter 5A described in Figure 9 is provided in the flow path 52 (first flow path) at the top of the cassette transfer station 2, and the chemical filter described in Figure 4The chemical filter 5 described in []. Moreover, air is supplied into the housing 20 serving as the first space and the housing 30 serving as the second space from the chemical filter 5A (the first chemical filter) and the chemical filter 5 (the second chemical filter), respectively.

[0121] In this example, considering that the concentration of various organic substances is relatively high around the processing station 3 where organic solvents are used, in order to improve the removal effect, a chemical filter 5 including an organic filtering section 55 is provided on the top of the processing station 3. On the other hand, considering that the concentration of organic substances is relatively low around the cassette transfer station 2 compared to that around the processing station 3, a chemical filter 5A that does not include the organic filtering section 55 is provided on the top of the cassette transfer station 2. Since it does not include the organic filtering section 55, for the chemical filter 5A, the acid filtering section 53 and the alkali filtering section 54 are formed relatively thick to effectively utilize the installed space, thereby achieving a long service life. Specifically, with respect to the thickness of the acid filtering section 53 and the thickness of the alkali filtering section 54, the thickness of the chemical filter 5A is made greater than the thickness of the chemical filter 5, thus achieving a long service life of the chemical filter 5A.

[0122] In Figure 20 Another installation example is shown. In this Figure 20 In the wafer processing system 1, for the processing station 3, the height of the area where the chemical filter can be installed is relatively large. Chemical filters 5 are provided on the tops of the cassette transfer station 2 and the processing station 3 respectively. However, with respect to the thickness of the organic filtering section 55, the thickness of the chemical filter 5 in the processing station 3 is greater than the thickness of the chemical filter 5 in the cassette transfer station 2 to effectively utilize the above-mentioned installable area. Thereby, a long service life of the chemical filter 5 in the processing station 3 is achieved.

[0123] Figure 21 Another other installation example is shown. In this example, it can also be set that by providing a chemical filter 5 on the top of the cassette transfer station 2, and on the other hand, providing Figure 10 a chemical filter 5B in which the thickness of the organic filtering section 55 shown in [] is greater than the thickness of other filtering sections on the top of the processing station 3, so that the chemical filter in the processing station 3 has a long service life.

[0124] As described above, between the chemical filters provided at different positions in the wafer processing system 1, it is possible to make the presence or absence of the organic filtering section 55 different, make the arrangement order of the included filtering sections in the flow path different, or make the thickness of any one of the included filtering sections different.

[0125] In addition, an example in which the thickness of the organic filter section 55 is different is shown for making the thickness of the filter section different between the chemical filters at different positions in the wafer processing system 1, but the thickness of the alkali filter section 54 and / or the acid filter section 53 may also be made different. Additionally, for ease of explanation, it is assumed that the concentration of organic substances around the processing station 3 is high, and the organic filter section 55 is provided at the processing station 3 or the organic filter section 55 is configured as a long-life chemical filter, but it is not limited to such a configuration. That is, the chemical filter described as being configured at the processing station 3 may be configured at the cassette transfer station 2, and the chemical filter described as being configured at the cassette transfer station 2 may be configured at the processing station 3. Moreover, it is shown that the structure of the chemical filter is different between the cassette transfer station 2 and the processing station 3, but the structure of the chemical filter may also be made different between other stations.

[0126] <System's partitioning structure>

[0127] As described above, the wafer processing system 1 as a substrate processing apparatus performs a series of patterning from the formation of a pattern-forming film to development, but it is not limited to such a system structure. It may also be configured such that a plurality of device units that each undertake a different part of the series of patterning are provided in the clean room. Moreover, it may be configured as the following wafer processing system: By sequentially transporting the cassette C between the device units using a transport mechanism in the clean room, and transporting the wafer W taken out from the cassette C within each device unit and performing processing, patterning processing is carried out. Since the substrate processing apparatus is a device that subjects the wafer W sent out from the cassette C to processing and returns it to the cassette C again, the plurality of device units correspond to respective substrate processing apparatuses. Thus, as the substrate processing apparatus, it may be configured as a device unit that undertakes a part of the processes in the patterning processing, and the chemical filter described above may be provided in each device unit.

[0128] Regarding further explanation of the device unit, if it is a device unit not connected to an exposure apparatus, it is provided with a cassette transfer station 2 for transporting the wafer W between the device unit and the cassette C and a processing station 3, and only the necessary processing apparatuses among the processing apparatuses described above need to be provided at the processing station 3. Additionally, if it is a device unit connected to an exposure apparatus, it is provided with a cassette transfer station 2 and an interface station 4, and it is sufficient to be able to transport the wafer W between the cassette C and the exposure apparatus via the cassette transfer station 2 and the interface station 4. When other processing than exposure is also carried out in this device unit, a processing station 3 is also provided.

[0129] In addition, for pattern formation, the processes of repeating PEB (Post Exposure Bake) and development may be performed. The second and subsequent PEB and development processes are for shaping the pattern formed on the resist film by the first PEB and development processes. For the device units that perform the second and subsequent PEB and development processes, the various chemical filters described above can also be applied. In addition, the pattern formation process refers to the process from forming the resist film for MOR to developing the resist film. However, in the case of repeating PEB and development, this development corresponds to the final development. Furthermore, when repeating PEB and development, the etching process of the film (lower layer film) under the resist film is not performed until the shaping is completed. That is, the process from forming the resist film to the final development before the etching of the lower layer film is first performed corresponds to pattern formation.

[0130] It has been described that the inert gas that has passed through the chemical filters described in the respective embodiments can be configured to be supplied to the cassette C and the standby devices provided in the station. By configuring to supply the inert gas in this way in a system that performs pattern formation using multiple device units, even if the timing of the transfer mechanism reaching a device unit is delayed, it is possible to suppress the deterioration of the resist film due to the long-term standby of the wafer W in the cassette C of a device unit, so this is preferable. In addition, the purpose is not to make the wafers W transferred to different device units standby, but rather to more reliably suppress the deterioration of the resist film before the wafers W are transferred to the transfer destination when transferring the wafers W within the same device unit, and thus the inert gas is supplied to the cassette C and the standby devices.

[0131] In addition, the materials constituting the filter units 53 to 55 have been exemplified. However, as long as each material can remove different chemical substances, the materials are not limited to those exemplified. For example, for the acid filter unit 53, activated carbon added with an alkaline substance such as potassium carbonate can be used, and for the alkali filter unit 54, activated carbon added with an acidic substance such as phosphoric acid can be used. In addition, the filter units 53 to 55 are not limited to the structures described above. For example, a filter unit configured by sandwiching a lot of granular activated carbon with non-woven fabric can also be used. Moreover, the substrate to be processed is not limited to a wafer. For example, it can also be a substrate for manufacturing a flat panel display or a mask substrate for manufacturing a mask for exposure. Therefore, a rectangular substrate can be processed.

[0132] <Supplement Regarding MOR>

[0133] Supplement the resist film of MOR. In the resist film, ligands coordinated to Sn atoms detach from the Sn atoms at the sites that have received exposure by the exposure apparatus, and many Sn atoms from which the ligands have detached bond to each other via oxygen (O) atoms. That is, Sn is oxidized to form a crosslinked structure, and a structure such as -Sn-O-Sn-O-Sn-O- is formed in the exposed area of the resist film. In addition, the ratio of Sn atoms to O atoms in the crosslinked structure is not limited to 1:1 in this way. By forming this crosslinked structure, the exposed sites become insoluble in the developing fluid, and PEB promotes the formation of this crosslinked structure. At the time of development, the unexposed areas where the crosslinked structure is not formed are removed.

[0134] <Examples of Other Structures of the Wafer Processing System>

[0135] Figure 22 The top view of the wafer processing system 1A is shown. The wafer processing system 1A is configured substantially the same as the wafer processing system 1. Hereinafter, the description will focus on the differences from the wafer processing system 1. In the description of this wafer processing system 1A, the side where the cassette transfer station 2 is located and the side where the interface station 4 is located are defined as the left side and the right side, respectively, and the side where the first module G1 is located and the side where the second module is located are defined as the front side and the rear side, respectively.

[0136] Chemical filters 5H are provided in the cassette transfer station 2, the processing station 3, and the interface station 4 instead of the chemical filter 5. In addition, the gas supply system 73 described in Figure 12 is connected to the wafer processing system 1A. A chemical filter 5H is also provided in the flow path 76 of the gas supply system 73 instead of the chemical filter 5.

[0137] The chemical filter 5H provided at each station is provided in the flow path 82 of a rectangular cylinder 81 whose internal structure is a gas flow path. Similar to the chemical filter 5, the chemical filter 5H includes an acid filtration section 53, a base filtration section 54, and an organic filtration section 55, but the arrangement order of these filtration sections is different from that of the chemical filter 5. The details of the chemical filter 5H will be described later.

[0138] In cassette transfer station 2, on the side wall on the left side of the housing 20, a cylinder 81 is provided at a position above the cassette placement plate 21. The upstream side of the flow path 82 formed by the cylinder 81 faces leftward and faces the external space of the housing 20. In each processing station 3, a cylinder 81 is provided on the upper wall of the housing 30. The upstream side of the flow path 82 formed by the cylinder 81 faces upward and faces the external space of the housing 30. In interface station 4, cylinders 81 are provided so as to protrude forward and backward from the front side wall and the rear side wall of the housing 40 respectively. The upstream side of the flow path 82 formed by the cylinder 81 on the front side faces forward and faces the external space of the housing 40, and the upstream side of the flow path 82 formed by the cylinder 81 on the rear side faces backward and faces the external space of the housing 40.

[0139] In this way, cylinders 81 equipped with chemical filters 5H are provided at stations 2, 3, and 4 respectively. Moreover, at each of stations 2, 3, and 4, the atmosphere outside the wafer processing system 1A is sucked through the chemical filter 5H provided at that station, and the atmosphere is supplied into the housings 20, 30, and 40 that constitute the stations. The suction and supply of this atmosphere are carried out by a fan 51 provided on the downstream side of the chemical filter 5H in the air flow path formed at each station. In addition, instead of sucking the atmosphere outside the wafer processing system 1A, for example, by connecting a supply pipe for supplying air whose temperature or humidity has been adjusted by an external device to the housing 81, air can be sucked in.

[0140] In addition, a filter 90 for removing foreign substances from the atmosphere is provided at a position on the downstream side of the fan 51 in the air flow path of this atmosphere, and this atmosphere is supplied into the housing through the filter 90. The filter 90 is, for example, a ULPA (Ultra Low Penetration Air) filter. As described above, an air flow path is formed at each station, and a chemical filter 5H, a fan 51, and a filter 90 are provided on the downstream side in this air flow path, and the above-mentioned cylinder 81 forms a part of this air flow path. After that, for convenience, the filter 90 is sometimes referred to as the foreign substance removal filter 90.

[0141] The processing station 3 will be further described. The atmosphere is supplied to the wafer transfer area 32 in the processing station 3 through an air flow path having a chemical filter 5H, a fan 51, and a foreign substance removal filter 90 provided in the housing 30 described above from above. And, as Figure 12 illustrated in the example, a gas whose temperature and humidity have been adjusted is supplied from the gas supply system 73 to the processing devices 70 included in the first module G1 and the second module G2 through the chemical filter 5H of the gas supply system 73.

[0142] Next, in Figure 23 the longitudinal sectional front view of Figure 24In the horizontal cross-sectional top view, the cassette transfer station 2 will be described in detail. In addition, the structures of the chemical filter 5H and the cylinder 81 will also be described in further detail. The cylinder 81 is constituted by connecting a respective metal cylinder 81A and cylinder 81B to each other in the axial direction of the cylinder via a connecting member 83. The cylinder 81A forms the upstream side of the flow path 82, and the cylinder 81B forms the downstream side of the flow path 82. The connecting member 83 is an elastic member formed in a ring shape along the circumferences of the cylinders 81A and 81B. Specifically, for example, it is a seal.

[0143] The chemical filter 5H is constituted by arranging an organic filtration section 55, an acid filtration section 53, and an alkali filtration section 54 in this order toward the downstream side of the flow path 82. The organic filtration section 55 and the acid filtration section 53 are provided inside the cylinder 81A, and the alkali filtration section 54 is provided inside the cylinder 81B. In this example, the organic filtration section 55 is a sheet containing activated carbon, the acid filtration section 53 is a sheet containing impregnated activated carbon, and the alkali filtration section 54 is a sheet containing a cation exchange resin. Each of these sheets is formed, for example, to incorporate fibers and is arranged in such a manner as to partition the flow path 82 into an upstream side and a downstream side. Moreover, as Figure 17 described in [ ], each of the filtration sections configured as sheets in this way becomes a corrugated shape by being bent.

[0144] Regarding such a mountain shape formed by bending the sheet, if the distance in the direction of the flow path 82 between adjacent peaks is defined as the apparent thickness L, then in this example, in order to achieve a long service life of the alkali filtration section 54, the apparent thickness L of the alkali filtration section 54 is greater than the apparent thickness L of the organic filtration section 55 and the acid filtration section 53. In addition, by making the apparent thickness L relatively large in this way, the volume of the space between the pleats formed by the sheets of the alkali filtration section 54 is also relatively large. As a result, the pressure loss when the gas passes through the region of the flow path 82 where the alkali filtration section 54 is provided is reduced. Therefore, in the case where the alkali filtration section 54 has a relatively high pressure loss when assumed to be in a flat shape, not only from the viewpoint of achieving a long service life of the alkali filtration section 54, but also from the viewpoint of reducing the pressure loss of the flow path 82, setting the relationship of the apparent thickness L of each filtration section as the above relationship is effective. In addition, the case where the alkali filtration section 54 has a relatively high pressure loss includes the case where the pressure loss is higher than the pressure loss of the organic filtration section 55 or the acid filtration section 53, which is also assumed to be in a flat shape.

[0145] In addition, in this example, since the apparent thickness L of the alkali filtration section 54 is made relatively large, the cylinder body 81 is relatively long. When integrally forming the cylinder body 81, due to its size, the manufacturing and processing difficulties may increase. Therefore, as described above, the cylinder body 81 is composed of cylinder bodies 81A and 81B that are separate components from each other, and these cylinder bodies 81A and 81B are connected via a connecting member 83. When each filtration section 53 to 55 is provided in such a cylinder body 81, since the connecting member 83 is provided, the space formed between the acid filtration section 53 and the alkali filtration section 54 becomes larger corresponding to the thickness of the connecting member 83. As Figure 18 shown in the example described in, the air that has passed through the acid filtration section 53 is diffused and supplied to the alkali filtration section 54 by using this space, thereby suppressing the decrease in the life at the local position of the alkali filtration section 54, which is thus preferable.

[0146] In the cassette transfer station 2, a plurality of, for example, three cylinder bodies 81 are arranged in the front-rear direction at the same height. Each cylinder body 81 is arranged in the housing 20 that constitutes the cassette transfer station 2 such that its axis extends in the left-right direction. As described above, the upstream side of the flow path 82 opens in the left side wall of the housing 20.

[0147] A suction housing 84 is provided on the right side of each cylinder body 81. The suction housing 84 forms a space 85 that is long in the front-rear direction and is partitioned from the surroundings. The downstream side of the flow path 82 of each cylinder body 81 is connected to this space 85. Two fans 51 are provided in the suction housing 84 such that their rotation axes extend in the left-right direction, and these fans 51 are located separately in the right side of the space 85 in the front-rear direction. Each fan 51 can suck the flow path 82 of each cylinder body 81 via the space 85. Thus, the flow path of one cylinder body 81 is sucked by a plurality of fans 51.

[0148] The upstream ends of the two pipes 86 are provided on the right side of the suction housing 84 in a front-rear arrangement and are respectively connected to the suction housing 84. The air sucked by the rear fan 51 among the two fans 51 is supplied to the flow path 87 in the rear pipe 86, and the air sucked by the front fan 51 is supplied to the flow path 87 in the front pipe 86. The downstream side of each pipe 86 extends downward and then bends to extend leftward. The lower side of the portion of each pipe 86 that extends leftward is open. Moreover, by providing a foreign matter removal filter 90 in a manner to block the open portion of the pipe 86 from below, the downstream end of the flow path 87 is located above the foreign matter removal filter 90 as a flat space. Thus, as Figure 23 shown, the flow path 87 is in the shape of a horizontally tilted letter L when viewed from the front, and the chemical filter 5H is located above the foreign matter removal filter 90.

[0149] The air is supplied from the outside of the wafer processing system 1A by the fan 51 into the flow path 87 in the pipe 86 via the chemical filter 5H and is supplied downward toward the foreign matter removal filter 90. The area below the foreign matter removal filter 90 to which the air is supplied is the area where the wafers W are transported by the wafer transfer devices 22 and 23.

[0150] In this way, a flow path from the chemical filter 5H to the foreign matter removal filter 90 is formed by the cylinder 81, the suction housing 84, and the pipe 86, and this flow path is bent in a manner that forms a laterally tilted letter U shape. Since the chemical filter 5H includes the filter portions 53 to 55, it is larger than a chemical filter having only one or two of the filter portions 53 to 55. However, as described above, by bending the flow path, even if the chemical filter 5H is arranged, it is possible to prevent the lateral enlargement of the flow path. In other words, according to the flow path structure of this example, it is possible to arrange a relatively large chemical filter 5H in the flow path direction without causing the flow path to enlarge laterally.

[0151] Next, the interface station 4 will be described with reference to Figure 25 the side view. The Figure 25 The interface station 4 is observed from the right side. A plurality of processing devices 70 are stacked on the rear side inside the housing 40 of the interface station 4 in this example. The processing performed by the processing device 70 is not limited, but for example, it is a process of cleaning the wafer W before exposure using an exposure device. In this interface station 4, a flow path is formed such that the air inhaled from different chemical filters 5H is supplied to mutually different areas. The supply destination of the air that has passed through the chemical filter 5H of the rear cylinder 81 is the processing device 70. Moreover, the supply destination of the air that has passed through the chemical filter 5H of the front cylinder 81 is the area where the wafer transfer devices 41 and 42 outside the processing device 70 move.

[0152] The front end of the cylinder 81 provided at the rear of the housing 40 is connected to a pipe 91 that extends obliquely upward from the side wall of the housing 40 when viewed from the side. The flow path 82 in the cylinder 81 and the flow path 94 formed by a flow path forming member 93 provided inside the housing 40 communicate with each other via the pipe 91. A fan 51 and a foreign matter removal filter 90 are provided on the downstream side of the flow path 94. The downstream end of the flow path forming member 93 is configured as a pipe, for example, and is connected to each processing device 70. According to the above structure, the air inhaled into the housing 40 by the fan 51 of the flow path 94 via the rear chemical filter 5H is supplied to each processing device 70 via the foreign matter removal filter 90.

[0153] The rear end of the cylinder 81 provided in front of the housing 40 is connected to the side wall of the housing 40. The flow path 82 in the cylinder 81 communicates with the flow path 96 formed by the flow path forming member 95 provided inside the housing 40. A fan 51 and a foreign matter removal filter 90 are provided on the downstream side of the flow path 96. According to the above structure, the air sucked into the housing 40 via the chemical filter 5H on the front side by the fan 51 in the flow path 96 is supplied to the moving areas of the wafer transfer devices 41 and 42 via the foreign matter removal filter 90.

[0154] For the interface station 4, similar to the processing station 3, the chemical filter 5H can also be provided on the upper part of the housing 40 of the station. However, as described above, by providing the chemical filter 5H on the side of the housing 40, the cylinder 81 is prevented from protruding from the upper wall of the housing 40. As a result, the height of the interface station 4 can be suppressed. For example, when the structural members of the exposure apparatus are located above the interface station 4, suppressing the height of the interface station 4 in this way is effective in preventing interference with the structural members.

[0155] Moreover, when the cylinder 81 having the chemical filter 5H is provided on the side wall of the housing 40 in this way, in the case where the cylinder 81 interferes with the member provided on the side wall of the housing 40, as exemplified by the rear cylinder 81, a structure is provided in which the pipe 91 is interposed between the cylinder 81 and the housing 40. Thus, it is only necessary to prevent this interference. Therefore, for the pipe 91, if there is no such interfering object, it can be not provided, and if it is necessary to provide, it can be provided between the front cylinder 81 and the wall portion of the housing 40. However, as Figure 25 shown, consider the case where the flow path from the cylinder 81 provided on the side wall of the housing 40 to the inside of the housing 40 via the pipe 91 is changed to a flow path in which the gas flowing from the side of the housing 40 to the inside and flowing inside flows downward. At this time, not only is it easy to prevent the above-mentioned interference, but since there is no upward flow path, it is easy to supply air to each processing device 70 located below the cylinder 81. If only the above-mentioned interference is to be prevented, the orientation of the pipe 91 can also be made horizontal, but the example of the present disclosure is more preferable in terms of efficient supply of air. In addition, in this interface station 4, the supply destination of the air that has passed through the chemical filter 5H on the rear side is set to the processing device 70, and the supply destination of the air that has passed through the chemical filter 5H on the front side is set to the transfer area of the wafer W, but the supply destination of the air can be appropriately set according to the arrangement position of the processing device 70 in the housing 40 and the like. Therefore, it can also be set to supply air to the processing device 70 via the chemical filter 5H on the front side.

[0156] In addition, Figure 23In the figure, the organic filter section 55 and the acid filter section 53 are shown as being separate from each other, but they may also be in contact. Additionally, in this example, the apparent thickness L of the alkali filter section 54 among the filter sections 53 to 55 is greater than the apparent thickness L of the other filter sections, but it is not limited to such a setting. The filter section with a larger apparent thickness L can be determined according to the environment in which the wafer processing system 1A is installed. Additionally, it is not limited to only making the apparent thickness L of a specific filter section greater than that of the other filter sections. Moreover, when the thickness of each filter section L is relatively small, the cylinder 81 is not limited to being composed of cylinders 81A and 81B. As Figure 26 shown, it may also be composed of only the cylinder 81B. In addition, the arrangement order of the filter sections 53 to 55 is not limited to Figure 23 , Figure 26 the example shown. It may also be set to the arrangement order described as other examples so far.

[0157] Moreover, in the structural example of the wafer processing system 1 described above before the wafer processing system 1A, the chemical filter is located on the downstream side of the fan 51, but it may also be configured such that the chemical filter is located on the upstream side of the fan 51 as in the wafer processing system 1A. Additionally, a foreign matter removal filter 90 is not shown in the wafer processing system 1, but it may also be provided in the same manner as the wafer processing system 1A.

[0158] An example is shown in which chemical filters 5 and 5H are provided in a wafer processing system for forming a resist film of MOR and a gas supply system 73 attached to the wafer processing system. However, the chemical filters 5 and 5H are not limited to being provided in such a system. Specifically, chemical filters 5 and 5H may also be mounted in a wafer processing system for forming a resist film using a chemically amplified resist and a gas supply system 73 attached to the wafer processing system. The wafer processing system for forming a chemically amplified resist film can be configured in the same manner as the wafer processing system described above, for example, except that the type of resist supplied to the wafer W is different.

[0159] It should be considered that the embodiments disclosed herein are illustrative in all respects and not restrictive. Without departing from the appended claims and their gist, the above embodiments can also be omitted, replaced, changed, and combined in various ways.

[0160] <Evaluation Test>

[0161] The following experiment was conducted: When performing a patterning process on a wafer W, a gas containing an organic compound was supplied to a region (designated as the first region) of a part of the surface of the wafer W at any stage, and the CD sizes were compared between the pattern formed in the first region and the pattern formed in the second region where the gas was not supplied. The stage at which the gas was supplied was any one of the first stage to the fourth stage. The first stage was before forming a resist film composed of MOR, the second stage was after forming the resist film and before performing exposure by an exposure apparatus. The third stage was after exposure and before performing PEB, and the fourth stage was after performing PEB and before performing development. In addition, in this evaluation experiment, development and PEB were not repeated.

[0162] Furthermore, in this evaluation experiment, as the exposure apparatus, an apparatus using KrF (krypton fluoride) as a light source was used. Also, regarding the gas containing the organic compound supplied, it was changed according to each wafer W. Specifically, gases obtained from each of the liquids of a mixed solution of PGMEA and acetic acid, PGMEA, acetic acid, a mixed solution of propylene glycol monomethyl ether and PEGMEA, hexamethyldisilazane, cyclohexanone, methyl ethyl ketone, and acetone were supplied. Regarding the mixed solution of PEGMEA and acetic acid, mixed solutions containing 2%, 5%, and 40% by weight of acetic acid were used respectively.

[0163] As a result of the evaluation experiment, for the wafer W to which a gas obtained from a mixed solution of PEGMEA and acetic acid or acetic acid gas was supplied at the second stage, the third stage, or the fourth stage, the CD sizes were different between the first region and the second region. More specifically, for the wafer W to which a gas containing acetic acid was supplied at the second stage or the third stage, the CD of the first region was smaller than the CD of the second region. For the wafer W to which a gas containing acetic acid was supplied at the fourth stage, the CD of the first region was larger than the CD of the second region. For other wafers W, no clear difference in the CD size was found between the first region and the second region. Based on the results of this evaluation experiment, it can be inferred that acetic acid causes a change in the CD of the pattern. Therefore, as described in the examples, it can be said that it is effective to include an organic filter section 55 in the chemical filter and to arrange the acid filter section 53 and the base filter section 54 in the order described in the embodiment to prevent the release of acetic acid generated from decomposed PGMEA.

Claims

1. A substrate processing apparatus for performing patterning by exposing and developing a metal-containing resist film formed on a substrate, wherein, a chemical filter is provided in a flow path for supplying gas into the substrate processing apparatus, and the chemical filter includes a plurality of filter parts arranged toward the downstream side and respectively removing different substances in the gas, among the plurality of filter parts, an acid filter part for removing acidic substances and an alkali filter part for removing alkaline substances are included.

2. The substrate processing apparatus according to claim 1, wherein, the acid filter part is provided on the downstream side of the alkali filter part.

3. The substrate processing apparatus according to claim 2, wherein, among the plurality of filter parts, an organic filter part for removing organic substances in the gas is included, and the organic filter part is provided on the upstream side of the alkali filter part in the flow path.

4. The substrate processing apparatus according to claim 1, wherein, among the plurality of filter parts, an organic filter part for removing organic substances in the gas is included, the acid filter part, the organic filter part, and the alkali filter part are sequentially provided toward the downstream side.

5. The substrate processing apparatus according to claim 1, wherein, as the chemical filter, a first chemical filter and a second chemical filter are provided, and the first chemical filter and the second chemical filter are respectively provided in a first flow path and a second flow path for supplying the gas into different spaces in the substrate processing apparatus, in the first chemical filter and the second chemical filter, at least any one of the presence or absence of an organic filter part for removing organic substances in the gas, the arrangement order of the filter parts, and the thickness of filter parts having the same removal object is different.

6. The substrate processing apparatus according to claim 5, wherein, only the first chemical filter among the first chemical filter and the second chemical filter includes the organic filter part, the thickness of the acid filter part in the second chemical filter is greater than the thickness of the acid filter part in the first chemical filter, or the thickness of the alkali filter part in the second chemical filter is greater than the thickness of the alkali filter part in the first chemical filter.

7. The substrate processing apparatus according to claim 1, wherein, a gap is provided between one filter part among the plurality of filter parts and another filter part provided behind the one filter part when observing the flow path toward the downstream side.

8. A substrate processing method for performing patterning by exposing and developing a metal-containing resist film formed on a substrate, wherein, the substrate processing method includes the following steps: supplying gas that has passed through a chemical filter including a plurality of filter parts into a substrate processing apparatus for performing the patterning, and the plurality of filter parts are arranged toward the downstream side in a flow path and respectively remove different substances in the gas, among the plurality of filter parts, an acid filter part for removing acidic substances and an alkali filter part for removing alkaline substances are included.

9. A chemical filter for a substrate processing apparatus for performing patterning by exposing and developing a metal-containing resist film formed on a substrate, wherein, The chemical filter includes a plurality of filtering portions, which are arranged toward the downstream side in a flow path for supplying gas into the substrate processing apparatus and respectively remove different substances in the gas. Among the plurality of filtering portions, an acid filtering portion for removing acidic substances and an alkali filtering portion for removing alkaline substances are included.

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