Exhaust system

Abstract

To efficiently treat the hydrogen gas emitted from an EUV lithography system. [Solution] The exhaust system is an exhaust system for exhausting hydrogen discharged from an EUV exposure apparatus, and comprises: a hydrogen pump module for a light source unit having a vacuum pump unit for sucking in hydrogen discharged from the light source unit of the EUV exposure apparatus; a first oxygen sensor module for measuring the oxygen concentration of the gas discharged from the hydrogen pump module for the light source unit; a hydrogen pump module for an exposure unit having a vacuum pump unit for sucking in hydrogen discharged from the exposure unit; a second oxygen sensor module for measuring the oxygen concentration of the gas discharged from the hydrogen pump module for the exposure unit; a hydrogen processing module for processing the hydrogen gas discharged from the first and second oxygen sensor modules; a utility module for supplying cooling water and nitrogen gas to each module; and a control module for supplying power and performing control.

Description

Technical Field

[0001] The present invention relates to an exhaust system for exhausting hydrogen and nitrogen discharged from an EUV exposure apparatus.

Background Art

[0002] In recent years, EUV (Extreme Ultra Violet) exposure apparatuses, which perform exposure processing on substrates such as wafers with extremely short wavelengths, have been put into practical use. EUV exposure apparatuses are ultra-precision instruments, and their performance decreases sharply particularly when foreign matter enters the optical system. An EUV exposure apparatus includes a light source unit that generates EUV and an exposure unit that exposes a substrate with the EUV generated by the light source unit. It is known that tin (Sn) oxide generated by laser irradiation of a target in the light source unit and organic substances desorbed from a photosensitive material (resist) in the exposure unit are typical contamination sources, respectively.

[0003] As a countermeasure against contamination of these components, there is a method using hydrogen gas. In the light source unit, several hundred liters per minute of hydrogen gas is used to remove tin oxide as gaseous hydride, and in the exposure unit, several tens of liters per minute of hydrogen gas is similarly used to gasify and remove organic substances. Most of the used hydrogen gas remains unreacted, but is discharged from the apparatus as a carrier for the removed contaminants. Therefore, exhaust gas containing a large amount of hydrogen gas of several hundred liters per minute is discharged from the EUV exposure apparatus.

[0004] As an apparatus for treating hydrogen gas discharged from an EUV exposure apparatus, an exhaust system is known in which hydrogen gas discharged from the EUV exposure apparatus is exhausted by a dry vacuum pump, and the exhausted hydrogen is safely treated by a hydrogen treatment apparatus (see Patent Document 1).

Prior Art Literature

Patent Literature

[0005]

Patent Document 1

Summary of the Invention

[0006] The present invention provides an exhaust system for treating hydrogen gas discharged from an EUV lithography apparatus, which can safely treat the discharged hydrogen gas using a dry vacuum pump, and then dilute, burn, recover, or a combination thereof. [Means for solving the problem]

[0007] [1] An exhaust system according to one embodiment is: An exhaust system for exhausting hydrogen and nitrogen emitted from an EUV lithography apparatus, A hydrogen pump module for a light source unit having a vacuum pump unit for sucking up hydrogen discharged from the light source unit of the EUV exposure apparatus, A first oxygen sensor module for measuring the oxygen concentration of the gas discharged from the hydrogen pump module for the light source unit, A hydrogen pump module for the exposure section having a vacuum pump unit for sucking up hydrogen discharged from the exposure section of the EUV exposure apparatus, A second oxygen sensor module for measuring the oxygen concentration of the gas discharged from the hydrogen pump module for the exposure unit, A hydrogen processing module for processing hydrogen gas discharged from the first and second oxygen sensor modules, A utility module for supplying cooling water and / or nitrogen gas to each module, A control module for supplying power to each of the aforementioned modules and for controlling each of the aforementioned modules, It is equipped with.

[0008] [2] An exhaust system according to one embodiment is described in [1] above, The hydrogen processing module includes a hydrogen dilution device for diluting the hydrogen gas, The air exhausted from each of the aforementioned modules is supplied to the hydrogen dilution device as dilution air.

[0009] [3] An exhaust system according to one embodiment is described in [1] or [2] above, The hydrogen treatment module includes a combustion-type exhaust gas treatment device that burns the hydrogen gas.

[0010] [4] An exhaust system according to one embodiment is, in any of the above [1] to [3], The system further includes a hydrogen recovery module for recovering the hydrogen gas and reusing it in the EUV exposure apparatus, The hydrogen recovery module includes a hydrogen purification device for purifying the recovered hydrogen gas.

[0011] [5] An exhaust system according to one embodiment is, in any of the above [1] to [4], The system further includes a fuel cell module for generating electricity using the aforementioned hydrogen gas.

[0012] [6] An exhaust system according to one embodiment is, in any of the above [1] to [5], The vacuum pump unit comprises a main pump, a first booster pump, and a second booster pump, and is equipped with casters at its bottom.

[0013] [7] An exhaust system according to one embodiment is, in any of the above [1] to [6], The system further includes a non-hydrogen pump module for exhausting gases other than hydrogen gas discharged from equipment other than the aforementioned EUV lithography apparatus. [Brief explanation of the drawing]

[0014] [Figure 1] This figure shows an example of a schematic configuration of the exhaust system according to the first embodiment. [Figure 2] This figure shows an example of a schematic configuration of the pump module according to this embodiment. [Figure 3] This diagram illustrates the installation method of the pump unit according to this embodiment. [Figure 4]It is a diagram showing an example of a schematic configuration of an exhaust system according to a second embodiment. [Figure 5] It is a diagram showing an example of a schematic configuration of an exhaust system according to a third embodiment. MODE FOR CARRYING OUT THE INVENTION

[0015] Hereinafter, each embodiment will be described with reference to the drawings. However, excessive detailed description may be omitted in some cases. For example, detailed description of already well-known matters and repeated description of substantially the same configuration may be omitted in some cases. This is to prevent the following description from becoming unnecessarily redundant and to facilitate understanding for those skilled in the art. <First Embodiment> Hereinafter, the present embodiment will be described with reference to the drawings. An exhaust system 10 according to an embodiment described below is used for an application of treating hydrogen used in an extreme ultraviolet exposure apparatus 1 (hereinafter referred to as EUV (Extreme Ultra Violet) exposure apparatus). The EUV exposure apparatus 1 generally includes a light source unit 2 that generates extreme ultraviolet (EUV), and an exposure unit 3 that exposes a workpiece such as a substrate, a wafer, or a panel with the extreme ultraviolet (EUV) generated by the light source unit 2. As described above, a large amount of hydrogen gas is used in the light source unit 2 and the exposure unit 3. This hydrogen gas is sent to the exhaust system 10 described below and is treated therein.

[0016] (Configuration of Exhaust System) Figure 1 shows an example of the schematic configuration of the exhaust system 10. As shown in Figure 1, the exhaust system 10 according to this embodiment is composed of multiple modules, and the number and type of each module can be changed according to the user's needs. As an example, the exhaust system 10 of this embodiment includes a group of hydrogen pump modules 11 for the light source unit (not shown) that sucks in hydrogen gas discharged from the light source unit 2 of the EUV exposure apparatus (consisting of at least one hydrogen pump module; as an example, it consists of n hydrogen pump modules 11-1 to 11-n), a first oxygen sensor module 12 that measures the oxygen concentration of the hydrogen gas discharged from the group of hydrogen pump modules 11 for the light source unit, a utility module 13, a control module 14 that controls the entire exhaust system 10, and a non-hydrogen pump module for exhausting non-hydrogen gases (air and nitrogen). The apparatus comprises a 15, a group of hydrogen pump modules 16 for the exposure section (consisting of at least one hydrogen pump module; for example, composed of n hydrogen pump modules 16-1 to 16-n) that suck in hydrogen gas discharged from the exposure section 3 of the EUV exposure apparatus 1, a second oxygen sensor module 17 that measures the oxygen concentration of the hydrogen gas discharged from the group of hydrogen pump modules 16 for the exposure section, and a first hydrogen processing module 18 and a second hydrogen processing module 19 for processing the hydrogen gas discharged from the hydrogen pump module group 11 for the light source section and the hydrogen pump module group 16 for the exposure section. The hydrogen pump module group 11 for the light source section and the hydrogen pump module group 16 for the exposure section have basically the same configuration.

[0017] (Enclosure exhaust 1: When the hydrogen processing module includes a hydrogen dilution device) First, the case of housing exhaust when the first hydrogen processing module 18 and the second hydrogen processing module 19 include a hydrogen dilution device will be described. The hydrogen pump module group 11 for the light source unit and the hydrogen pump module group 16 for the exposure unit, the first oxygen sensor module 12 and the second oxygen sensor module 17, the utility module 13, the control module 14, and the non-hydrogen pump module 15 are provided with exhaust ports to which housing exhaust pipes (not shown) are appropriately connected, and air intake ports (not shown). The air exhausted from the housing of each of these modules can be used as dilution air for diluting hydrogen in the hydrogen dilution device described later. Therefore, the user of the exhaust system 10 does not need to prepare a separate housing exhaust for the purpose of diluting hydrogen.

[0018] Furthermore, the suction pressure (airflow) is high at the enclosure exhaust points close to the hydrogen processing modules 18 and 19, while it is low at the points further away due to the influence of conductance. Therefore, dampers are provided at each exhaust port to balance the airflow of each enclosure exhaust.

[0019] Furthermore, if particles or iron powder enter the hydrogen processing module, and these particles are charged, static electricity may be generated in the hydrogen processing modules 18 and 19, potentially becoming an ignition source. For this reason, filters are provided at each enclosure exhaust port to prevent particles from entering the hydrogen processing modules 18 and 19.

[0020] Furthermore, if the air exhausted from each module to the enclosure is routed solely through the hydrogen dilution unit, then if the hydrogen dilution unit (main and spare) malfunctions and stops during hydrogen exhaust from the exposure apparatus, enclosure exhaust will become impossible. In that situation, if there is a hydrogen leak in any module, the hydrogen will accumulate inside the module. To prevent this, the enclosure exhaust pipe may be connected to at least one factory exhaust pipe. This allows for the safe exhaust of hydrogen from inside the enclosure even in the aforementioned situation.

[0021] (Enclosure exhaust 2: When the hydrogen processing module does not include a hydrogen dilution device) Next, the case where the first hydrogen processing module 18 and the second hydrogen processing module 19 do not include a hydrogen dilution device will be described. The hydrogen pump module group 11 for the light source unit and the hydrogen pump module group 16 for the exposure unit, the first oxygen sensor module 12 and the second oxygen sensor module 17, the utility module 13, the control module 14, and the non-hydrogen pump module 15 are provided with exhaust ports to which housing exhaust pipes (not shown) are appropriately connected, and air intake ports (not shown). The air inside each module is discharged through the housing exhaust pipe. The housing exhaust pipe is connected to the factory's exhaust equipment (not shown), and negative pressure is created inside the housing and inside the housing exhaust pipe. Therefore, even if hydrogen leaks inside the housing, it is prevented from leaking outside the exhaust system. Also, even if the housing exhaust pipe is damaged, it is prevented from leaking hydrogen gas from the housing exhaust pipe.

[0022] (Hydrogen pump module for light source) Hydrogen gas discharged from the light source unit 2 of the EUV exposure apparatus (not shown) is drawn into a hydrogen pump module for the light source unit (first hydrogen pump module) 11 through a manifold. The hydrogen pump module group 11 for the light source unit is equipped with a vacuum pump unit VP that sucks in the hydrogen gas discharged from the light source unit of the EUV exposure apparatus (not shown). The vacuum pump mounted on this vacuum pump unit VP is, for example, a positive displacement dry vacuum pump, but the specific configuration is not particularly limited. The exhaust system 10 of this embodiment is configured to suck in the hydrogen gas discharged from the light source unit 2 of the EUV exposure apparatus 1 using the hydrogen pump module group 11 for the light source unit. The hydrogen pump module group 11 for the light source unit may also be composed of multiple hydrogen pump modules (in the example shown in Figure 1, it is composed of n hydrogen pump modules, 11-1 to 11-n). This allows the hydrogen gas to be continuously sucked in by the other hydrogen pump module even if the operation of one hydrogen pump module is stopped for maintenance, etc. Therefore, maintenance of the hydrogen pump module can be performed without stopping the operation of the EUV exposure apparatus 1.

[0023] Figure 2 shows an example of the schematic configuration of a hydrogen pump module included in the hydrogen pump module group 11 for the light source unit of this embodiment. As an example, hydrogen pump module 11-2 included in the hydrogen pump module group 11 for the light source unit will be described, but the basic configuration is the same for the other hydrogen pump modules included in the hydrogen pump module group 11 for the light source unit and for hydrogen pump modules 16-1 to 16-n included in the hydrogen pump module group 16 for the exposure unit.

[0024] As shown in Figure 2, the hydrogen pump module 11-2 houses a vacuum pump unit VP equipped with casters C. Power is supplied to this vacuum pump unit VP from the power busbar 11a.

[0025] The vacuum pump unit VP consists of three vacuum pumps (main pump MP, first booster pump BP1, and second booster pump BP2). By operating the three vacuum pumps of the vacuum pump unit VP, hydrogen gas is drawn into the vacuum pump unit VP from the light source unit 2 of the EUV exposure apparatus 1 through the intake pipe 11b connected to the intake port. The intake pipe 11b is equipped with an air-driven valve 11c and a manual valve 11d. When replacing any of the vacuum pumps in the vacuum pump unit VP, the air-driven valve 11c is controlled to close automatically, but a manual valve 11d is also provided to ensure safe operation even if the air-driven valve 11c malfunctions. Alternatively, instead of installing the manual valve 11d, a locking mechanism may be provided on the air-driven valve 11c to physically prevent the valve position from changing even if there is incorrect air-driven operation.

[0026] The hydrogen gas drawn in by the vacuum pump unit VP is exhausted through the exhaust pipe 11e, where it merges with the hydrogen gas exhausted from the adjacent upstream module (hydrogen pump module 11-3) and is then exhausted to the adjacent downstream module (hydrogen pump module 11-1). This exhaust pipe 11e is also equipped with an air-driven valve 11c and a manual valve 11d.

[0027] Furthermore, the hydrogen pump module 11-2 is equipped with an air intake port 11f, an exhaust port 11g, and a pump P. Therefore, when the pump P is operated, air is drawn into the housing of the hydrogen pump module 11-2 from the outside via the air intake port 11f and exhausted from the housing via the exhaust port 11g. As a result, even if hydrogen gas leaks out from the vacuum pump unit VP, intake pipe 11b, exhaust pipe 11e, etc., this gas will be exhausted from the housing of the hydrogen pump module 11-2 along with the air drawn in, thus preventing hydrogen gas from leaking into the factory.

[0028] Furthermore, a hydrogen sensor H is provided inside the housing of the hydrogen pump module 11-2 to detect the leakage of hydrogen gas from the vacuum pump unit VP, intake pipe 11b, exhaust pipe 11e, etc. When the hydrogen sensor H (hydrogen detector) detects a hydrogen leak, a detection signal is sent to the control module 14. The control module 14 outputs a signal to notify the user of the abnormal condition. For example, the hydrogen leak may be notified to the user via a display unit or speaker provided in at least one module of the exhaust system 10.

[0029] Furthermore, based on the detection signal output from the hydrogen sensor H or the notification signal output from the control module 14, it is possible to control the system so that the hydrogen supply to the EUV exposure apparatus 1 is shut off for safety. In addition, the exhaust system 10 can be safely shut down by closing the automatic valves (air-driven valves) installed upstream of all vacuum pumps based on the same signal, thereby stopping the hydrogen supply to the exhaust system 10. Furthermore, the number of hydrogen pump modules included in the hydrogen pump module group 11 for the light source section of the exhaust system 10 can be changed according to user requirements. For example, if the user's requirements change after the exhaust system 10 has been installed and a higher exhaust speed is needed, it is possible to add more hydrogen pump modules later. For example, the system may be equipped with 3 to 8 hydrogen pump modules for the light source section.

[0030] Figure 3 illustrates the method for installing the vacuum pump unit VP into the hydrogen pump module. As an example, hydrogen pump module 11-2 included in the hydrogen pump module group 11 for the light source section will be described, but the same applies to other hydrogen pump modules included in the hydrogen pump module group 11 for the light source section and the hydrogen pump module group 16 for the exposure section.

[0031] As shown in Figure 3, the vacuum pump unit VP of this embodiment is equipped with casters (wheels) C. Conventionally, multiple vacuum pumps were not configured as a single unit, but rather consisted of two units, for example, a first unit having a first booster pump BP1 and a second unit having a second booster pump BP2 and a main pump MP. As a result, a jig was required to lift each unit to the height of the housing installation position, which led to problems such as the time required to install the vacuum pumps.

[0032] On the other hand, in this embodiment, the vacuum pump unit is configured with multiple vacuum pumps (first booster pump BP1, second booster pump BP2, and main pump MP) as a single unit (pump unit), and casters C are provided on the vacuum pump unit VP. Therefore, the vacuum pump unit VP can be easily installed in the hydrogen pump module simply by moving it horizontally. This significantly reduces the time required for the installation of the vacuum pump unit VP.

[0033] Returning to Figure 1, the hydrogen gas discharged from each vacuum pump unit of the hydrogen pump module group 11 for the light source is transferred to the first oxygen sensor module 12 through the pump exhaust pipe.

[0034] (First oxygen sensor module) The first oxygen sensor module 12 is installed downstream of the hydrogen pump module group 11 for the light source unit and monitors the oxygen concentration of the gas in the pump exhaust pipe. The gas in the pump exhaust pipe is basically composed of hydrogen gas, but there may be cases where air flows in from the outside due to damage to the manifold or pump exhaust pipe. Therefore, the first oxygen sensor module 12 is configured to constantly measure the oxygen concentration of the gas in the pump exhaust pipe and generate an alarm signal according to the measured oxygen concentration. Specifically, the first oxygen sensor module 12 includes at least one oxygen sensor 12a mounted on a branch line branching off from the pump exhaust pipe, and an oxygen concentration monitoring device (not shown) that generates an alarm signal when the oxygen concentration measured by the oxygen sensor 12a is higher than a threshold. The measured oxygen concentration is sent to the oxygen concentration monitoring device. The oxygen concentration monitoring device compares the measured oxygen concentration with a preset threshold, and if it is higher than the threshold, it generates an alarm signal. This alarm signal is sent to the user's equipment of the EUV exposure apparatus 1 and exhaust system 10, and the hydrogen supply to the EUV exposure apparatus 1 is stopped. Specifically, the valve supplying hydrogen to the EUV lithography apparatus 1 is closed, stopping the supply of hydrogen to the EUV lithography apparatus.

[0035] The gas in the pump exhaust pipe that has passed through the first oxygen sensor module 12 enters the first and second hydrogen processing modules 18 and 19 via the utility module 13, control module 14, non-hydrogen pump module 15, hydrogen pump module group 16 for exposure section, and second oxygen sensor module 17.

[0036] (Utility module) The utility module 13 is a module that receives cooling water and nitrogen gas (N2) from the factory and distributes them to each module. The utility module 13 supplies the cooling water supplied from the factory to the hydrogen pump module group 11 for the light source section, the hydrogen pump module group 16 for the exposure section, and the non-hydrogen pump module 15, respectively.

[0037] The cooling water is used to cool the casing, motor, etc., of each vacuum pump unit VP, and is then recovered from the utility module 13 and drained through the factory's wastewater line (not shown).

[0038] Furthermore, the utility module 13 supplies nitrogen gas (N2) supplied from the factory to the hydrogen pump module group 11 for the light source unit, the hydrogen pump module group 16 for the exposure unit, the non-hydrogen pump module 15, the first oxygen sensor module 12, and the second oxygen sensor module 17.

[0039] Nitrogen supplied from the utility module 13 (with one supply port) is branched and supplied to the hydrogen pump module group 11 for the light source section, the hydrogen pump module group 16 for the exposure section, the non-hydrogen pump module 15, the first and second oxygen sensor modules 12 and 17, and the solenoid valves (air-driven valves) for driving the valves of each module. Nitrogen gas supplied to the vacuum pump unit VP is used for purging and shaft sealing.

[0040] Furthermore, the nitrogen gas supplied from the utility module 13 to the non-hydrogen pump module 15 is used for the shaft seal of the vacuum pump unit VP.

[0041] Furthermore, the nitrogen gas supplied from the utility module 13 to the first and second oxygen sensor modules 12 and 17 is used as a standard gas for accurately measuring oxygen concentration.

[0042] The nitrogen gas used by the hydrogen pump module group 11 for the light source, the hydrogen pump module group 16 for the exposure unit, the non-hydrogen pump module 15, and the first and second oxygen sensor modules 12 and 17 merges with the hydrogen gas pump exhaust pipe and is exhausted together with the hydrogen gas to the hydrogen processing module 18.

[0043] (Control module) The control module 14 supplies power from the factory to each module and controls the pumps, sensors, and other components contained within each module.

[0044] (Non-hydrogen pump module) The non-hydrogen pump module 15 is a module for exhausting air other than hydrogen gas, such as nitrogen gas, from the vacuum section (vacuum robot section / reticle stage section) of the EUV exposure apparatus 1, excluding the light source section 2 and the exposure section 3.

[0045] Specifically, the non-hydrogen pump module 15 includes a vacuum pump VP1 that draws in gas exhausted from the vacuum robot section, a vacuum pump VP2 that draws in gas exhausted from the reticle stage section, and a spare vacuum pump VP3 (not shown) in case either vacuum pump VP1 or vacuum pump VP2 is unable to operate for any reason. If either vacuum pump VP1 or VP2 fails, the faulty pump can be replaced without stopping the operation of the vacuum robot section and the reticle stage section by switching to the spare vacuum pump VP3.

[0046] Furthermore, in this embodiment, the non-hydrogen pump module 15 shares a spare pump (vacuum pump VP3) between the vacuum pump VP1 for the vacuum robot and the vacuum pump VP2 for the reticle stage. This allows the size of the non-hydrogen pump module 15 to be smaller compared to the case where one spare pump is provided for each of the vacuum pumps VP1 and VP2.

[0047] The gas discharged from the vacuum pumps VP1 to VP3 of the non-hydrogen pump module 15 is exhausted outside the factory (into the atmosphere) through the factory exhaust pipe (not shown).

[0048] (Hydrogen pump module for exposure section) Hydrogen gas discharged from the exposure section 3 of the EUV exposure apparatus 1 is drawn into the hydrogen pump module group 16 for the exposure section through a manifold. The basic configuration of the hydrogen pump modules 16-1 to 16-n included in this hydrogen pump module group 16 for the exposure section is the same as that of the hydrogen pump modules 11-1 to 11-n included in the hydrogen pump module group 11 for the light source section.

[0049] Each of the hydrogen pump module groups 16 for the exposure section is equipped with a vacuum pump unit VP that sucks in hydrogen gas discharged from the exposure section 3 of the EUV exposure apparatus 1. The vacuum pump mounted on this vacuum pump unit VP is, for example, a positive displacement dry vacuum pump, but the specific configuration is not particularly limited. The exhaust system 10 of this embodiment is configured to suck in hydrogen gas discharged from the exposure section 3 of the EUV exposure apparatus 1 using the hydrogen pump module group 16 for the exposure section. Furthermore, the hydrogen pump module group 16 for the exposure section may be composed of multiple hydrogen pump modules (in the example shown in Figure 1, it is composed of n hydrogen pump modules, 16-1 to 16-n). This allows hydrogen gas to be continuously sucked in by the other hydrogen pump modules even if the operation of one hydrogen pump module is stopped for maintenance, etc. Therefore, maintenance of the hydrogen pump modules can be performed without stopping the operation of the EUV exposure apparatus 1.

[0050] The hydrogen gas discharged from the vacuum pump unit VP of the hydrogen pump module group 16 for the exposure section is transferred to the second oxygen sensor module 17 through the pump exhaust pipe.

[0051] (Second oxygen sensor module) The second oxygen sensor module 17 is located downstream of the hydrogen pump module group 16 for the exposure unit and monitors the oxygen concentration of the gas in the pump exhaust pipe. The gas in the pump exhaust pipe is basically composed of hydrogen gas, but there may be cases where air flows in from the outside due to damage to the manifold or pump exhaust pipe. Therefore, the second oxygen sensor module 17 is configured to constantly measure the oxygen concentration of the gas in the pump exhaust pipe and generate an alarm signal according to the measured oxygen concentration. Specifically, the second oxygen sensor module 17 includes at least one oxygen sensor 17a mounted on a branch line branching off from the pump exhaust pipe, and an oxygen concentration monitoring device (not shown) that generates an alarm signal when the oxygen concentration measured by at least one of the oxygen sensors 17a is higher than a threshold. The measured oxygen concentration is sent to the oxygen concentration monitoring device. The oxygen concentration monitoring device compares the measured oxygen concentration with a preset threshold, and if it is higher than the threshold, it generates an alarm signal. The alarm signal is sent to the upstream EUV exposure apparatus 1, and the hydrogen supply to the EUV exposure apparatus 1 is stopped.

[0052] The gas in the pump exhaust pipe that has passed through the second oxygen sensor module is transferred to the first and second hydrogen processing modules.

[0053] (Hydrogen processing module) The hydrogen treatment modules (first and second hydrogen treatment modules 18 and 19) are devices for treating hydrogen gas discharged from the light source unit 2 side (hydrogen pump module group 11 for the light source unit) and the exposure unit 3 side (hydrogen pump module group 16 for the exposure unit) of the EUV exposure apparatus 1. Specifically, the first and second hydrogen treatment modules 18 and 19 are equipped with a hydrogen dilution device that dilutes the hydrogen gas to a concentration below the lower explosive limit, or a combustion-type exhaust gas treatment device (combustion abatement device) that burns the hydrogen gas by bringing it into contact with a flame. When the first hydrogen treatment module 18 and / or the second hydrogen treatment module 19 are used as hydrogen dilution devices, the air exhausted from the housing of each module is used as dilution air. As a result, the user of the exhaust system 10 does not need to separately install equipment to supply dilution air to the hydrogen dilution device.

[0054] The first and second hydrogen processing modules 18 and 19 are configured such that the first hydrogen processing module 18 primarily processes hydrogen gas, and if the first hydrogen processing module 18 is unable to operate for any reason, the second hydrogen processing module 19 acts as a backup, processing hydrogen gas in place of the first hydrogen processing module 18. If the second hydrogen processing module 19 is also unable to operate for any reason, the gas is exhausted directly to the outside of the factory (into the atmosphere) through the factory exhaust pipe (not shown). Alternatively, the hydrogen gas may be processed by both the first and second hydrogen processing modules 18 and 19 at all times.

[0055] The gas processed in the first hydrogen treatment module 18 and / or the second hydrogen treatment module 19 is exhausted outside the factory (into the atmosphere) through a factory exhaust pipe (not shown).

[0056] As described above, in the exhaust system 10 according to this embodiment, each module (hydrogen pump module group 11 for the light source unit, first oxygen sensor module 12, utility module 13, control module 14, non-hydrogen pump module 15, hydrogen pump module group 16 for the exposure unit, second oxygen sensor module 17, first hydrogen processing module 18, and second hydrogen processing module 19) is configured as a separable module, so it is possible to increase or decrease each module according to the user requirements of the exhaust system 10. <Second Embodiment> Next, the exhaust system 10A according to the second embodiment will be described. In the exhaust system 10 according to the first embodiment, hydrogen gas discharged from the EUV exposure apparatus is processed by the first and second hydrogen processing modules, whereas the exhaust system 10A of the second embodiment differs in that it includes a hydrogen recovery module 20 for recovering hydrogen gas discharged from the EUV exposure apparatus 1 and reusing it in the EUV exposure apparatus 1, and also includes a hydrogen processing module 19 as a backup.

[0057] Figure 4 shows an example of a schematic configuration of the exhaust system 10A according to the second embodiment. Components common to the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0058] As shown in Figure 4, the hydrogen gas discharged from the light source unit 2 side (hydrogen pump module group 11 for the light source unit) and the exposure unit 3 side (hydrogen pump module group 16 for the exposure unit) of the EUV exposure apparatus 1 is first transferred to the hydrogen recovery module 20.

[0059] The hydrogen recovery module 20 has a hydrogen purification device for purifying hydrogen gas. The hydrogen gas purified by this device is transferred to the EUV exposure apparatus 1 through a hydrogen transfer pipe and reused.

[0060] Furthermore, if the hydrogen purification system cannot be operated for any reason, the hydrogen gas is transferred to the hydrogen processing module 19 and processed by a hydrogen treatment device (hydrogen dilution device or combustion-type exhaust gas treatment device). If the hydrogen treatment device also cannot be operated for any reason, the gas is discharged directly out of the factory (into the atmosphere) through the factory exhaust pipe (not shown).

[0061] Thus, in this embodiment, the exhaust system is designed to recover and reuse the hydrogen gas discharged from the EUV exposure apparatus 1, allowing for effective utilization of the hydrogen gas without releasing it into the atmosphere as exhaust gas. <Third Embodiment> Next, the exhaust system 10B according to the third embodiment will be described. In the exhaust system 10 according to the first embodiment, the hydrogen gas discharged from the EUV exposure apparatus 1 is processed by the first and second hydrogen processing modules 18 and 19, whereas the exhaust system 10B of the third embodiment differs in that it includes a fuel cell module 21 for generating electricity using the hydrogen gas discharged from the EUV exposure apparatus 1, and a hydrogen processing module 19 for backup.

[0062] Figure 5 shows an example of the schematic configuration of the exhaust system 10B according to the third embodiment. Components common to the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0063] As shown in Figure 5, the hydrogen gas discharged from the light source unit 2 side (hydrogen pump module group 11 for the light source unit) and the exposure unit 3 side (hydrogen pump module group 16 for the exposure unit) of the EUV exposure apparatus 1 is first transferred to the fuel cell module 21.

[0064] The fuel cell module 21 has a fuel cell unit for generating electricity using hydrogen gas. Hydrogen gas discharged from the light source unit 2 side (hydrogen pump module group 11 for the light source unit) and the exposure unit 3 side (hydrogen pump module group 16 for the exposure unit) of the EUV exposure apparatus 1 is supplied to this fuel cell unit. Oxygen from the air is also supplied to the fuel cell unit through an air intake (not shown), and electricity is generated using hydrogen gas and oxygen. The electricity generated by the fuel cell is supplied to the factory's power supply equipment (factory power line) via electrical cables.

[0065] Furthermore, if the fuel cell unit is unavailable for any reason, the hydrogen gas is transferred to the hydrogen processing module 19 and processed by a hydrogen treatment device (hydrogen dilution device or combustion-type exhaust gas treatment device). If the hydrogen treatment device is also unavailable for any reason, the gas is discharged directly into the atmosphere outside the factory through the factory exhaust pipe (not shown).

[0066] Thus, in the exhaust system 10B of this embodiment, the hydrogen gas discharged from the EUV exposure apparatus 1 is used to generate electricity with the fuel cell module 21, so that the hydrogen gas can be effectively utilized without being discharged into the atmosphere as exhaust gas.

[0067] As described above, the present invention is not limited to the embodiments described above, and the components can be modified and implemented in practice without departing from the spirit of the invention. Furthermore, various inventions can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiments. Moreover, components from different embodiments may be appropriately combined. [Explanation of symbols]

[0068] 10 Exhaust System 11. Hydrogen pump module for light source (first hydrogen pump module) 12. First Oxygen Sensor Module 13 Utility Modules 14 Control Module 15 Non-hydrogen pump modules 16. Hydrogen pump module for exposure section (second hydrogen pump module) 17. Second oxygen sensor module 18. First hydrogen processing module 19. Second Hydrogen Processing Module 20 Hydrogen recovery modules 21 Fuel cell modules

Claims

1. An exhaust system for exhausting hydrogen emitted from an EUV lithography apparatus, A hydrogen pump module for a light source unit having a vacuum pump unit for sucking up hydrogen discharged from the light source unit of the EUV exposure apparatus, A first oxygen sensor module for measuring the oxygen concentration of the gas discharged from the hydrogen pump module for the light source unit, A hydrogen pump module for the exposure section having a vacuum pump unit for sucking up hydrogen discharged from the exposure section of the EUV exposure apparatus, A second oxygen sensor module for measuring the oxygen concentration of the gas discharged from the hydrogen pump module for the exposure unit, A hydrogen processing module for processing hydrogen gas discharged from the first and second oxygen sensor modules, A utility module for supplying cooling water and / or nitrogen gas to each module, A control module for supplying power to each of the aforementioned modules and for controlling each of the aforementioned modules, An exhaust system equipped with this feature.

2. The hydrogen processing module includes a hydrogen dilution device for diluting the hydrogen gas, The air exhausted from each of the aforementioned modules is supplied to the hydrogen dilution device as dilution air. The exhaust system according to claim 1.

3. The hydrogen treatment module includes a combustion-type exhaust gas treatment device for burning the hydrogen gas. The exhaust system according to claim 1.

4. The apparatus further comprises a hydrogen recovery module for recovering the hydrogen gas and reusing the hydrogen gas in the EUV exposure apparatus, The hydrogen recovery module includes a hydrogen purification device for purifying the recovered hydrogen gas. The exhaust system according to claim 1.

5. The system further comprises a fuel cell module for generating electricity using the aforementioned hydrogen gas. The exhaust system according to claim 1.

6. The vacuum pump unit comprises a main pump, a first booster pump, and a second booster pump, and is equipped with casters at its bottom. The exhaust system according to claim 1.

7. The system further includes a non-hydrogen pump module for exhausting gases other than hydrogen gas discharged from equipment other than the aforementioned EUV exposure apparatus. The exhaust system according to claim 1.

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