Contaminant trap unit and light source device

Abstract

A contaminant trap unit and a light source device are provided that can improve the maintenance efficiency of a film trap. A contaminant trap unit according to an embodiment of the present invention comprises a detachable member and at least one film trap. The contaminant trap unit is attached to an opening of a chamber main body having an outlet for plasma radiation and an opening different from the outlet. The detachable member covers the opening and is configured to be attached to / detachable from the chamber main body. The at least one film trap comprises a plurality of films for trapping contaminants from the plasma and is connected to the detachable member such that the plurality of films are arranged on a path of radiation from the plasma to the outlet, wherein the detachable member is attached to the chamber main body.

Description

Technical area

[0001] The present invention relates to an impurity trap unit that traps impurities emitted from a plasma and a light source device. Background of the invention

[0002] X-rays are commonly used for medical, industrial, and research applications.

[0003] In the medical field, X-rays are used for applications such as chest radiography, dental radiography, and computed tomography (CT).

[0004] In industry, X-rays are used for non-destructive testing and tomographic non-destructive testing, among other things, to examine the interior of materials such as structures and welds.

[0005] In research, X-rays are used for applications such as X-ray diffraction to analyze the crystal structure of materials and X-ray spectroscopy (X-ray fluorescence analysis) to analyze the composition of materials.

[0006] Extreme ultraviolet light (hereinafter referred to as EUV light) with a wavelength of 13.5 nm, which is in the soft X-ray range and has a relatively long wavelength among X-rays, has recently been used as exposure light.

[0007] Here, the base material of an EUV lithography mask with fine patterns is a reflective mirror with a stacked structure in which a multilayer film (e.g., molybdenum and silicon) is provided for reflecting EUV light on a low thermal expansion glass substrate.

[0008] A material that absorbs radiation with a wavelength of 13.5 nm is then patterned on the multilayer film to form an EUV mask.

[0009] In addition, the size of unacceptable defects in EUV masks is much smaller than in conventional ArF masks, and the unacceptable defects are difficult to detect.

[0010] In this context, EUV masks are tested with radiation whose wavelength corresponds to the wavelength used in lithography, which is commonly referred to as actinic testing.

[0011] For example, if the actinic test is performed using radiation with a wavelength of 13.5 nm, it can detect defects with a resolution of better than 10 nm.

[0012] EUV light source devices generally include a discharge-generated plasma (DPP) light source device, a laser-assisted discharge-generated plasma (LDP) light source device, and a laser-generated plasma (LPP) light source device.

[0013] The DPP light source device applies a high voltage between electrodes, between which a gaseous plasma raw material (discharge gas) containing EUV radiation species is supplied to generate a high-temperature, high-density plasma by the discharge, utilizing the extreme ultraviolet light emitted by the plasma.

[0014] The LDP light source device is obtained by improving the DPP light source device. For example, a liquid high-temperature plasma raw material (e.g., Sn (tin), Li (lithium), etc.) containing EUV radiation species is supplied to the surface of the electrode (discharge electrode) where the discharge is generated. The material is then irradiated with an energy beam (e.g., electron beam, laser beam, etc.) to evaporate the material, and then high-temperature plasma is generated by the discharge.

[0015] The LPP light source device generates high-temperature plasma by exciting EUV radiation species with a laser beam or the like. This type of light source device includes a light source device that generates plasma by condensing a laser beam onto a droplet of Sn (tin) or Li (lithium) ejected as a tiny liquid droplet, which is a target material for EUV radiation, thereby exciting the target material. Furthermore, an LPP light source device includes a device that supplies a liquid high-temperature plasma raw material containing EUV radiation species to a surface of a rotating body and irradiates the surface of the rotating body with an energy beam (laser beam) to generate plasma.

[0016] In this way, the method for generating EUV light using plasma is also applicable to an apparatus that generates not only EUV light but also X-rays having a wavelength shorter than that of EUV light by changing the type of plasma raw materials or the excitation energy for generating the plasma.

[0017] Incidentally, impurities are dispersed from the high-speed plasma generated by these light source devices. These impurities include particles of high-temperature plasma raw materials, material particles from electrodes and rotating bodies sputtered during plasma generation, and the like. If such impurities enter an application device that uses radiation such as EUV light, they may damage or contaminate optical elements such as reflective films in the application device. As a result, the performance of the application device may deteriorate.

[0018] To prevent contaminants dispersed by the plasma from entering the application device, a debris mitigation device (also called a debris mitigation tool (DMT)) is proposed, which traps contaminants between the plasma and the application device. The debris mitigation device is typically constructed using a foil trap. The foil trap is a contaminant trap that traps contaminants using a thin, plate-like foil.

[0019] For example, Patent Literature 1 describes a fixed film trap and a rotating film trap. The rotating film trap rotates a plurality of radially arranged films with a rotating shaft as the center, causing the contaminants and the films to collide with each other to capture the contaminants. The fixed film trap divides a space with a plurality of films located at fixed positions, increases the pressure of the atmospheric gas in the space, and causes the contaminants and the atmospheric gas to collide with each other to capture the contaminants. The use of these film traps makes it possible to capture particles with a small number of atoms, atoms in a neutral or ionic state, etc., from micrometer-sized droplets, which belong to a relatively large size category among contaminants. Citation listPatent literature

[0020] Patent Literature 1: Japanese Patent Application Publication No. 2017-219698 Disclosure of the inventionTechnical problem

[0021] For example, impurities that have entered the film trap adhere to the films and the elements around the films and flow down to be collected in a storage bin. However, some of the impurities remain attached to the films and the like. For example, with increasing operating time, the amount of impurities adhering to the films may increase, and the impurity capture rate by the film trap may deteriorate. Furthermore, in a rotating film trap, the weight of the films increases due to the adhesion of impurities, which can lead to unstable rotation.

[0022] For this reason, maintenance, such as removing contaminants adhering to the films and the like, or replacing the film trap, is required when using the film trap. As described above, the film trap is provided between a light source part that generates plasma and an application device. Therefore, to release the film trap, for example, it is necessary to detach and disassemble the light source part or the like, and perform adjustment after assembly, resulting in time-consuming maintenance of the film trap.

[0023] In view of the circumstances described above, it is an object of the present invention to provide a contaminant trap unit and a light source device that can improve the efficiency of maintenance of a film trap. Solution to the problem

[0024] To achieve the above object, a contaminant trap unit according to an embodiment of the present invention comprises a detachable member and at least one film trap.

[0025] The contaminant trap unit is attached to an opening of a chamber main body having an outlet for plasma radiation, the opening being different from the outlet.

[0026] The detachable element covers the opening and is configured to be attached to / removed from the chamber main body.

[0027] The at least one foil trap comprises a plurality of foils for trapping contaminants from the plasma and is connected to the detachable member such that the plurality of foils are arranged on a path of radiation from the plasma to the outlet, the detachable member being attached to the chamber main body.

[0028] In this contaminant trap unit, the at least one film trap comprising the plurality of films for trapping impurities from the plasma is connected to the detachable member that covers the opening of the chamber main body and is attached to / detached from the chamber main body. When the detachable member is attached, the plurality of films are arranged on the radiation path from the plasma to the outlet. Furthermore, when the detachable member is detached, the film trap can be removed together. This can improve the efficiency of film trap maintenance.

[0029] The at least one film trap may comprise a rotating film trap having a plurality of films and a rotating member radially supporting the plurality of films. In this case, the contaminant trap unit may further comprise: a shaft portion connected to the rotating member of the rotating film trap; and a rotation drive portion that rotates the shaft portion.

[0030] The rotary drive section can be connected to an outer side of the detachable element. In this case, the shaft section can penetrate the detachable element. Furthermore, the rotating element can be connected to the shaft section inside the detachable element.

[0031] The contaminant trap unit may further comprise a reinforcing member configured as a separate member from the detachable member and fixing the rotation drive portion to the detachable member.

[0032] The detachable member may include a reinforcing portion that reinforces the rigidity of a portion to which the rotation drive portion is connected.

[0033] The at least one foil trap may comprise a fixed foil trap having a plurality of foils and a fixed member that fixes the plurality of foils.

[0034] The contaminant trap unit may further comprise a film trap cover connected to the detachable member, enclosing an outer peripheral portion of the rotating film trap, and trapping the contaminants scattered by the rotating film trap. In this case, the fixed film trap may be connected to the film trap cover.

[0035] The contaminant trap unit may further include a gas introduction tube penetrating the detachable member and introducing a transparent gas into the fixed film trap, the transparent gas being transparent to radiation.

[0036] The contamination trap may further include a condensing mirror connected to the detachable element that condenses the radiation from the plasma. In this case, the at least one foil trap is arranged between the plasma and the condensing mirror.

[0037] The contaminant trap unit may further comprise a position adjustment mechanism that adjusts the arrangement of the condensation mirror.

[0038] The contaminant trap unit may further comprise a vibration isolation mechanism that suppresses vibration transmitted to the chamber main body and / or the condensing mirror.

[0039] The contaminant trap unit may further comprise at least one of the following elements: a heat shield element connected to the detachable element and disposed between the plasma and the foil trap, or a detection sensor connected to the detachable element and detecting a state of the plasma.

[0040] The detachable member may include a guide mechanism that guides an attachment position relative to the chamber main body.

[0041] A light source device according to an embodiment of the present invention includes a plasma generation section, a chamber main body, and the impurity trap unit described above.

[0042] The plasma generation section converts a plasma raw material into plasma.

[0043] The chamber main body includes an outlet for the radiation of the plasma generated by the plasma generation section and an opening different from the outlet. Advantageous effects of the invention

[0044] As described above, according to the present invention, it is possible to improve the maintenance efficiency of a film trap. Note that the effects described herein are not necessarily limiting, and any effect described in the present disclosure can be provided. Short description of the drawings [ Fig. 1] Fig. 1 is a schematic cross-sectional view showing a configuration of an EUV light source device having an impurity trap unit according to a first embodiment of the present invention. [ Fig. 2] Fig. 2 is a schematic view showing a configuration example of the impurity trap unit according to the first embodiment. [ Fig. 3] Fig. 3 is a schematic view showing a state in which the impurity trap unit is detached. [ Fig. 4] Fig. 4 is a schematic cross-sectional view showing a configuration example of a rotating film trap. [ Fig. ] Fig. 5 is a schematic front view showing a configuration example of the rotating film trap. [ Fig. 6] Fig. 6 is a schematic view showing another configuration example of the impurity trap unit. [ Fig. 7] Fig. 7 is a schematic view showing another configuration example of the impurity trap unit. [ Fig. 8] Fig. Figure 8 is a schematic cross-sectional view showing an example of the configuration of a fixed film trap. [ Fig. 9] Fig. 9 is a schematic front view showing a configuration example of the fixed film trap. [ Fig. 10] Fig. 10 is a schematic view showing a configuration example of a contaminant trap unit having a film trap cover. [ Fig. 11] Fig. 11 is a schematic view showing a configuration example of a contaminant trap unit having a heat shield plate. [ Fig. 12] Fig. 12 is a schematic cross-sectional view showing a configuration example of an EUV light source device having an impurity trap unit according to a second embodiment. [ Fig. 13] Fig. 13 is a schematic plan view showing a configuration example of an RFF beam section. [ Fig. ] Fig. 14 is a schematic perspective view showing a configuration example of a condensing mirror. [ Fig. 15] Fig. 15 is a schematic view showing another configuration example of the impurity trap unit including the condensation mirror. [ Fig. 16] Fig. 16 is a schematic view showing another configuration example of the impurity trap unit including the condenser mirror. [ Fig. 17] Fig. 17 is a schematic view showing another configuration example of the impurity trap unit including the condensation mirror. Mode(s) of carrying out the invention

[0045] Hereinafter, embodiments according to the present invention will be described with reference to the drawings. <Erste Ausführungsform> [Configuration of the light source device]

[0046] Fig. 1 is a schematic cross-sectional view showing a configuration of an EUV light source device with an impurity trap unit according to a first embodiment of the present invention. In this embodiment, an extreme ultraviolet light source device (EUV light source device) using laser-assisted discharge plasma (LDP) is exemplified as the EUV light source device 100. Furthermore, the EUV light source device 100 is connected to an application device 110 that uses EUV light and functions as a light source of the application device 110.

[0047] Note that in the figure, the X-axis, the Y-axis, and the Z-axis represent three mutually orthogonal axial directions, and the Z-axis corresponds to a vertical direction (gravity direction). Therefore, Fig. 1 is a cross-sectional view of the EUV light source device 100 taken along the horizontal direction. [Overall configuration]

[0048] In Fig. 1, the EUV light source device 100 emits extreme ultraviolet light (EUV light). The wavelength of this extreme ultraviolet light is, for example, 13.5 nm.

[0049] Specifically, the EUV light source device 100 irradiates liquid-phase plasma raw materials SA and SB, which are respectively supplied to the surfaces of a pair of discharge electrodes EA and EB that generate a discharge, with an energy beam such as a laser beam LB to vaporize the plasma raw materials SA and SB. Subsequently, a plasma P is generated by discharge in a discharge region D between the discharge electrodes EA and EB. EUV light is emitted from the plasma P.

[0050] The application device 110 is, for example, a mask inspection device for lithography. In this case, a portion of the EUV light emitted by the plasma P is extracted from an outlet 16 (light extraction section) and guided to the mask inspection device. The mask inspection device uses the EUV light emitted from the outlet 16 of the EUV light source device 100 as inspection light to perform mask blank or pattern inspection. The use of EUV light can support 5 nm to 7 nm processes.

[0051] In this embodiment, the EUV light corresponds to radiation obtained from a plasma, and the EUV light source device 100 corresponds to a light source device. Furthermore, the mask inspection device is an example of an application device that uses radiation from the plasma.

[0052] The EUV light source device 100 includes a chamber main body 1, a light source section 2, a contaminant trap unit 30, and an impurity storage section not shown in the figure. The light source section 2 generates EUV light based on the LDP method in the chamber main body 1. The impurity trap unit 30 is an impurity reduction device attached to the chamber main body 1 and traps impurities DB scattered along with the EUV light emitted from the light source section 2. The impurity storage section stores impurities generated by the light source section 2, impurities trapped by the impurity trap unit 30, and the like. (Chamber main body)

[0053] The chamber main body 1 is a main body of a vacuum enclosure (vacuum chamber) that generates plasma P and maintains a negative pressure atmosphere to extract EUV light from the plasma P. The chamber main body 1 is connected to the application device 110 (mask inspection device) that uses EUV light.

[0054] As in Fig. 1, the chamber main body 1 in this embodiment includes a light source chamber 11 and a connection chamber 15.

[0055] The light source chamber 11 is a vacuum vessel that separates the plasma P generated inside from the outside environment.

[0056] The light source chamber 11 forms a plasma generation chamber in which the light source section 2 that generates the plasma P is housed. The light source chamber 11 is a vacuum housing made of a rigid body, such as metal, and its interior is maintained in a reduced pressure atmosphere at a predetermined pressure or below by a vacuum pump (not shown) to successfully generate a discharge for heating and exciting the plasma raw materials SA and SB and suppressing the attenuation of the EUV light.

[0057] A transparent window 12 for introducing the laser beam LB is provided in a side wall 11a of the light source chamber 11. Furthermore, a through-hole 13 communicating with the connecting chamber 15 is provided in a side wall 11b of the light source chamber 11.

[0058] The connection chamber 15 is a pressure-reduced container that connects the light source chamber 11 and the application device 110. The connection chamber 15 is connected to the side wall 11b of the light source chamber 11, and the interior of the connection chamber 15 communicates with the interior of the light source chamber 11 via the through-hole 13. The connection chamber 15 is a vacuum housing made of a rigid body, such as metal, and its interior is maintained in a negative pressure atmosphere at a predetermined pressure or lower to suppress the attenuation of the EUV light, as in the light source chamber 11.

[0059] The connecting chamber 15 comprises the outlet 16 and an opening 17.

[0060] The outlet 16 is an optical window for introducing the EUV light incident from the through hole 13 into the application device 110, and functions as a light extraction section that extracts the EUV light in the EUV light source device 100. In the Fig. In the example shown in Figure 1, the outlet 16 is provided in a side wall 15a of the connecting chamber 15.

[0061] The opening 17 is a mounting opening to which the contaminant trap unit 30 is attached and is located at a different position than the outlet 16. In Fig. 1, the opening 17 is schematically represented by the dashed area.

[0062] In this way, the chamber main body 1 (connection chamber 15) includes the outlet 16 for the EUV light from the plasma P and the opening 17 different from the outlet 16. In addition, the impurity trap unit 30 to be described later is attached to the opening 17. Note that in the Fig. 1, two chambers (light source chamber 11 and connection chamber 15) are connected to each other to form the chamber main body 1. The chamber main body 1 is not limited to the above embodiments and may, for example, be configured as a vacuum housing using a single element or may be configured by combining two or more elements to form a single vacuum housing as a whole. (Light source section)

[0063] The light source section 2 converts the plasma raw material into plasma to generate plasma P, from which EUV light is emitted. In this embodiment, the light source section 2 corresponds to a plasma generation section that converts a plasma raw material into plasma.

[0064] The light source section 2 includes a pair of discharge electrodes EA and EB. The discharge electrodes EA and EB are disc-shaped elements that have the same shape and size. For example, the discharge electrode EA serves as the cathode, and the discharge electrode EB serves as the anode. The discharge electrodes EA and EB are made of a refractory metal such as molybdenum (Mo), tungsten (W), or tantalum (Ta). The discharge electrodes EA and EB are arranged spaced apart from each other, and the peripheral portions of the discharge electrodes EA and EB are located close to each other.

[0065] At this time, the discharge region D in which the plasma P is generated is located in a gap between the discharge electrodes EA and EB in which the peripheral portions of the discharge electrodes EA and EB are closest to each other.

[0066] A container CA, in which the liquid-phase plasma raw material SA is collected, and a container CB, in which the liquid-phase plasma raw material SB is collected, are arranged within the light source chamber 11. Heated liquid-phase plasma raw materials SA and SB are supplied to the containers CA and CB, respectively. The liquid-phase plasma raw materials SA and SB are, for example, tin (Sn), but can also be lithium (Li).

[0067] In the container CA, the liquid-phase plasma raw material SA is stored so that the lower part of the discharge electrode EA is immersed in the plasma raw material SA. In the container CB, the liquid-phase plasma raw material SB is stored so that the lower part of the discharge electrode EB is immersed in the plasma raw material SB. Therefore, the liquid-phase plasma raw materials SA and SB adhere to the lower parts of the discharge electrodes EA and EB, respectively. The liquid-phase plasma raw materials SA and SB, adhering to the lower parts of the discharge electrodes EA and EB, are transported to the discharge region D where the plasma P is to be generated, along with the rotation of the discharge electrodes EA and EB.

[0068] The discharge electrode EA is coupled to a rotary shaft JA of a motor MA and rotates about an axis of the discharge electrode EA. The discharge electrode EB is coupled to a rotary shaft JB of a motor MB and rotates about an axis of the discharge electrode EB. The motors MA and MB are arranged outside the light source chamber 11, and the rotary shafts JA and JB of the respective motors MA and MB penetrate the light source chamber 11 and extend from the outside to the inside of the light source chamber 11. The space between the rotary shaft JA and the wall of the light source chamber 11 is sealed with a sealing member PA, and the space between the rotary shaft JB and the wall of the light source chamber 11 is sealed with a sealing member PB. The sealing members PA and PB are, for example, mechanical seals. The sealing members PA and PB support the rotary shafts JA and JB, respectively.JB and at the same time ensure a negative pressure atmosphere in the light source chamber 11.

[0069] The EUV light source device 100 further includes a controller 20, a pulse power supply section 21, a laser source (energy beam irradiation device) 22, and a movable mirror 23. The controller 20, the pulse power supply section 21, the laser source 22, and the movable mirror 23 are installed outside the light source chamber 11. The controller 20 controls the operation of each section of the EUV light source device 100, as described later. For example, the controller 20 controls the rotation drive of the motors MA and MB to rotate the discharge electrodes EA and EB at a predetermined rotation speed. In addition, the controller 20 controls the operation of the pulse power supply section 21, the irradiation timing of the laser beam LB from the laser source 22, and the like.

[0070] Two power supply lines QA and QB extending from the pulse power supply section 21 pass through the feedthroughs FA and FB, respectively, and are connected to the containers CA and CB, respectively, disposed within the light source chamber 11. The feedthroughs FA and FB are sealing members embedded in the wall of the light source chamber 11 to maintain a negative pressure atmosphere within the light source chamber 11. The containers CA and CB are made of an electrically conductive material, and the plasma raw materials SA and SB stored in the containers CA and CB are also electrically conductive materials such as tin. The lower parts of the discharge electrodes EA and EB are immersed in the plasma raw materials SA and SB stored in the containers CA and CB, respectively.When the pulse power supply section 21 supplies pulse power to the containers CA and CB, this pulse power is supplied to the discharge electrodes EA and EB via the plasma raw materials SA and SB, respectively.

[0071] The pulse power supply section 21 supplies the pulse current to the discharge electrodes EA and EB to generate a discharge in the discharge region D. The plasma raw materials SA and SB, which are transported to the discharge region D with the rotation of the discharge electrodes EA and EB, are then heated and excited by an electric current flowing between the discharge electrodes EA and EB during the discharge, so that a plasma P is generated from which EUV light is to be emitted.

[0072] The laser source 22 irradiates the plasma raw material SA adhering to the discharge electrode EA and transported to the discharge region D with the laser beam to vaporize the plasma raw material SA. The laser source 22 is, for example, an Nd:YVO4 (neodymium-doped yttrium orthovanadate) laser device.

[0073] The laser source 22 emits the laser beam LB in the infrared range with a wavelength of 1064 nm.

[0074] However, the energy beam irradiation device may also be a device that emits an energy beam other than the laser beam LB, provided that it can evaporate the plasma raw material SA.

[0075] The laser beam LB emitted by the laser source 22 is directed onto the movable mirror 23 via a condensing means including a condensing lens 24, for example. The condensing means adjusts the spot diameter of the laser beam LB at a laser beam irradiation position of the discharge electrode EA. The condensing lens 24 and the movable mirror 23 are arranged outside the light source chamber 11.

[0076] The laser beam LB converged by the condensing lens 24 is reflected by the movable mirror 23, passes through the transparent window 12 provided in the side wall 11a of the light source chamber 11, and is directed onto the discharge electrode EA near the discharge region D. The position of the discharge electrode EA, to which the laser beam LB is applied, is adjusted by adjusting the posture of the movable mirror 23. Note that the adjustment of the posture of the movable mirror 23 may be performed manually by an operator, or the controller 20 may control the posture of the movable mirror 23 based on intensity information of the EUV light from a detection sensor 82, which will be described later. In this case, the movable mirror 23 is driven by a movable mirror driving section, the illustration of which is omitted.

[0077] To facilitate the irradiation of the laser beam LB onto the peripheral portion of the discharge electrode EA near the discharge region D, the axes of the discharge electrodes EA and EB are not parallel. The distance between the rotary shafts JA and JB is narrower on the motor side MA and MB and wider on the discharge electrode side EA and EB. This makes it possible to bring the facing surfaces of the discharge electrodes EA and EB closer together, while retracting the opposite sides of the facing surfaces of the discharge electrodes EA and EB from the irradiation path of the laser beam LB, thereby facilitating the irradiation of the laser beam LB onto the peripheral portion of the discharge electrode EA near the discharge region D.

[0078] The discharge electrode EB is arranged between the discharge electrode EA and the movable mirror 23. The laser beam LB reflected by the movable mirror 23 passes near the outer peripheral surface of the discharge electrode EB and then reaches the outer peripheral surface of the discharge electrode EA. To prevent the laser beam LB from being blocked by the discharge electrode EB, the discharge electrode EB is directed toward the motor side MB (left side of Fig. 1) is retracted relative to the discharge electrode EA. The liquid-phase plasma raw material SA adhering to the outer peripheral surface of the discharge electrode EA near the discharge region D is vaporized by irradiation with the laser beam LB and supplied to the discharge region D as the gas-phase plasma raw material SA.

[0079] The pulse power supply section 21 supplies current to the discharge electrodes EA and EB to generate plasma P in the discharge region D (converting the gas-phase plasma raw material SA into plasma). When the gas-phase plasma raw material SA is supplied to the discharge region D by irradiation with the laser beam LB, a discharge is generated between the discharge electrodes EA and EB in the discharge region D. When a discharge is generated between the discharge electrodes EA and EB, the gas-phase plasma material SA in the discharge region D is heated and excited by an electric current, thereby generating plasma P. EUV light emitted from the generated plasma P enters the connection chamber 15 through the through-hole 13 provided in the side wall 11b of the light source chamber 11. [Contaminant trap unit configuration]

[0080] Fig. 2 is a schematic view showing a configuration example of the impurity trap unit according to the first embodiment.

[0081] Fig. 3 is a schematic view showing a state in which the impurity trap unit is detached. Fig. 2 and Fig. 3 are cross-sectional views of the Fig. 1 in the vertical direction. The illustration of the light source section 2 that generates the plasma P is omitted here.

[0082] First, a configuration of the connecting chamber 15 (chamber main body 1) to which the impurity trap unit 30 is attached will be described with reference to Fig. 2 described.

[0083] As described above, the connection chamber 15 includes the outlet 16 for EUV light and the opening 17 to which the contaminant trap unit 30 is attached.

[0084] The outlet 16 is typically a through-opening and is connected to an inlet 111 for EUV light provided on the outside of the application device 110. In this case, the interior of the connection chamber 15 communicates with the interior of the application device 110 via the outlet 16.

[0085] In the example of Fig. 2, the outlet 16 is provided at the bottom of the side wall 15a of the connecting chamber 15, and EUV light traveling from the plasma P to the lower right in the figure is extracted from the outlet 16. Furthermore, a connecting flange 18 is provided that connects the outlet 16 and the inlet 111 of the application device 110. The opening diameters of the outlet 16 and the connecting flange 18 are adjusted according to the beam diameter of the EUV light output to the application device 110, or the like.

[0086] Note that the outlet 16 may be provided with, for example, a transparent member such as an optical filter that transmits the EUV light. Furthermore, a valve, a gate, or the like may be provided to open and close the path from the connection chamber 15 to the application device 110. Such a configuration makes it possible to operate the negative pressure atmosphere on the EUV light source device 100 side and the negative pressure atmosphere on the application device 110 side independently of each other. For example, the connection chamber 15 can be opened to the atmosphere while maintaining the negative pressure atmosphere in the application device 110, facilitating maintenance.

[0087] The opening 17 is provided in the connecting chamber 15 so that the contents of the contaminant trap unit 30 can be added and removed. As shown in Fig. As shown in Figure 2, the opening 17 in this embodiment is provided from the top of the connection chamber 15 to the side wall 15a where the outlet 16 is located. The shape, size, position, or the like of the opening 17 is not limited and can be adjusted in accordance with the optical path of the EUV light, the configurations of the light source section 2 and the impurity trap unit 30, and the like.

[0088] The impurity trap unit 30 is attached to the opening 17 of the connecting chamber 15 (chamber main body 1) and traps impurities DB discharged from the plasma P. In other words, the impurity trap unit 30 is a contaminant reduction device DMT attached for use to the chamber main body 1. The impurity trap unit 30 includes a detachable member 31, a film trap FT, a rotary shaft 32, and a rotation drive section 33. (Detachable element)

[0089] The detachable member 31 is a member that covers the opening 17 and is configured to be attached to / detached from the connection chamber 15 (chamber main body 1). In other words, the detachable member 31 functions as a lid for closing the opening 17 and also as an outer wall of the vacuum housing formed by the connection chamber 15.

[0090] Hereinafter, the side of the detachable element 31 facing the interior of the chamber is referred to as the inside of the detachable element 31 and the opposite side is referred to as the outside of the detachable element 31.

[0091] The detachable member 31 is a metal structural member configured to support the film trap FT, the rotary shaft 32, and the rotation drive section 33 while maintaining the negative pressure atmosphere inside the connection chamber 15. Aluminum or the like is used as the material for the detachable member 31. Furthermore, a sealing member (illustrated here) is provided at the contact point between the detachable member 31 and the connection chamber 15 to prevent leakage and maintain the negative pressure atmosphere.

[0092] In the example of Fig. 2, the detachable element 31 with an L-shaped cross-section is mounted so as to cover the opening 17 provided from the top of the connection chamber 15 to its side. The detachable element 31 is typically attached to the connection chamber 15 by screwing.

[0093] The specific shape of the detachable element 31 is not limited. For example, if the Fig. 2 has a cylindrical shape with a bottom as a whole, the detachable member 31 has a shape obtained by cutting out a part including a side surface and a bottom surface of the cylindrical column. Furthermore, when the connecting chamber 15 has the shape of a rectangular parallelepiped as a whole, the detachable member 31 has an L-shape obtained by cutting out a rectangular parallelepiped with two mutually orthogonal surfaces. When the opening 17 is provided in the plane, the detachable member 31 is a flat, plate-like member that closes the opening 17.

[0094] In addition, the detachable element 31 comprises a guide mechanism 34 that defines an attachment position with respect to the connecting chamber 15 (chamber main body 1). In the example of Fig. 2, a guide pin 34a and a guide hole 34b configured to fit each other are used as the guide mechanism 34. For example, the guide pin 34a is provided at a position where the guide pin 34a contacts the detachable member 31 on the outside of the connection chamber 15. The guide hole 34b, into which each guide pin 34a is to be inserted, is located on the inside of the detachable member 31. Note that the specific configuration of the guide mechanism 34 is not limited, and, for example, a slot and a rib configured to fit each other can be used.

[0095] The guide mechanism 34 is provided so that the detachable element 31 can be precisely mounted at a predetermined mounting position. Furthermore, once the detachable element 31 is mounted, adjustment of the mounting position or the like is virtually unnecessary. This can prevent, for example, a situation in which the sealing element is damaged due to displacement of the detachable element 31 during alignment.

[0096] It should be noted that the guide mechanism 34 does not necessarily have to be present.

[0097] Furthermore, the detachable element 31 is provided with a through-hole 35. This through-hole 35 is a hole for the rotary shaft 32 to pass through. Additionally, a handle or the like may be provided on the outside of the detachable element 31 to support the entire contaminant trap unit 30. (foil trap)

[0098] The impurities DB are ejected along with the EUV light from the plasma P generated in the light source section 2 at high speed in various directions. The impurities DB contain Sn particles, which are the plasma raw materials SA and SB, and material particles of the discharge electrodes EA and EB that were sputtered during the generation of the plasma P. The impurities DB acquire large kinetic energy through the contraction and expansion processes of the plasma P. In other words, the impurities DB generated from the plasma P contain fast-moving ions, neutral particles, and electrons. If such impurities DB reach the application device 110, the impurities DB may damage or contaminate a reflective film and similar optical elements in the application device 110, thereby degrading their performance.

[0099] In this context, the impurity trap unit 30 is provided with a film trap FT to prevent the impurities DB from entering the application device 110. The film trap FT is an impurity trap disposed within the connection chamber 15 (chamber main body 1) and traps the impurities DB from the plasma P with a plurality of films F. The use of the film trap FT makes it possible to trap impurities ranging from, for example, large millimeter-sized impurities to small atomic-sized impurities. In this embodiment, the part comprising a plurality of films F and trapping the impurities DB is referred to as the film trap FT.

[0100] The film trap FT is connected to the detachable member 31 so that the plurality of films F are arranged on the path of the EUV light from the plasma P to the outlet 16, wherein the detachable member 31 is fixed to the connecting chamber 15 (chamber main body 1).

[0101] The path of the EUV light from the plasma P to the outlet 16 refers here to a path through which the EUV light emitted from the outlet 16 passes. In the Fig. In the example shown in Figure 2, a linear path is formed that leads directly from the plasma P to the outlet 16. The plurality of foils F are arranged along this path.

[0102] It should be noted that the multiple foils F are not necessarily arranged on a straight line connecting the plasma P and the outlet 16. For example, a reflecting mirror or the like may be provided in the connecting chamber 15 to change the outlet direction of the EUV light. In this case, the multiple foils F are arranged on the path of the EUV light between the plasma P and the reflecting mirror to trap the impurities DB toward the reflecting mirror.

[0103] The fact that the foil trap FT is connected to the detachable element 31 also means that the foil trap FT is connected to the plurality of foils F directly or indirectly to the detachable element 31. Typically, the foil trap FT and the detachable element 31 are indirectly connected to one another via one or more elements, but a configuration in which the foil trap FT is directly connected to the detachable element 31 is also conceivable.

[0104] The foil trap FT and the detachable element 31 are connected to each other so that the foil trap FT can also be attached / removed together with the detachable element 31.

[0105] As a film trap FT, examples include a rotating film trap equipped with a process that causes the multiple films F to actively collide with contaminants, and a fixed film trap in which the positions of the multiple films F are fixed. The rotating film trap is also called a rotating film trap (RFF). Furthermore, the fixed film trap is also called a static film trap (SFF).

[0106] In Fig. 2, the case in which only a rotating film trap 36 is mounted is described as an example of the contaminant trap unit 30. It should be noted that a contaminant trap unit equipped with both the rotating film trap 36 and a fixed film trap (see Fig. 7, etc.), and a contamination trap unit equipped with only a fixed foil trap can be configured. (rotating film trap)

[0107] Fig. 4 is a schematic cross-sectional view showing an embodiment of the rotating film trap 36. Fig. 5 is a schematic front view showing an embodiment of the rotating film trap 36. As shown in the Fig. 4 and Fig. 5, the rotating film trap 36 comprises a plurality of films (vanes) F, a central support post 37 and an outer ring 38.

[0108] Each of the plurality of foils F is a thin film or a thin flat plate. The central support post 37 is a member that radially supports the plurality of foils F. The outer ring 38 is arranged concentrically with the central support post 37 and is connected to the tip of each foil F, which extends radially from the central support post 37. In this embodiment, the central support post 37 corresponds to a rotating member.

[0109] Each foil F is arranged radially around the central support post 37 at approximately equal angular intervals.

[0110] Each foil F is located on the plane containing the central axis C0 of the central support post 37. The material of the rotating foil trap 36 is, for example, a refractory metal such as tungsten (W) or molybdenum (Mo).

[0111] As in Fig. 5, the plurality of films F of the rotating film trap 36 are arranged parallel to the light beam direction of the EUV light so as not to block the EUV light coming from the plasma P (emission point) toward the outlet 16. In other words, the rotating film trap 36, in which each film F is arranged in the plane containing the central axis C0 of the central support post 37, is arranged so that the plasma P (emission point) lies in the extension of the central axis C0 of the central support post 37 (see Fig. 2). Thus, the EUV light is blocked only by the thickness of each film F, except for the central support post 37 and the outer ring 38, which makes it possible to maximize the fraction of EUV light passing through the rotating film trap 36 (also called transmittance). (rotating shaft)

[0112] Back to Fig. 2, the rotating shaft 32 is a columnar long member and is connected to the central support post 37 of the rotating film trap 36. In this embodiment, the rotating shaft 32 corresponds to a shaft section.

[0113] In this embodiment, the rotary shaft 32 is arranged to pass through the through hole 35 of the detachable element 31.

[0114] The central support post 37 of the rotating film trap 36 is connected to an end portion of the rotating shaft 32 disposed inside the detachable member 31. Specifically, the rotating shaft 32 and the central support post 37 are connected to each other such that the center axis of the rotating shaft 32 and the center axis C0 of the central support post 37 are aligned with each other. Furthermore, the rotation drive portion 33 is connected to an end portion of the rotating shaft 32 disposed inside the detachable member 31 (an end portion opposite the side to which the rotating film trap 36 is connected).

[0115] In addition, the contaminant trap unit 30 has a structure for receiving the rotary shaft 32 with a mechanical seal 39. As shown in Fig. As shown in Figure 2, the through-hole 35 in the detachable element 31 is designed larger than the diameter of the rotating shaft 32. The gap between the rotating shaft 32 and the through-hole 35 is sealed by the mechanical seal 39. The mechanical seal 39 rotatably supports the rotating shaft 32 of a motor 40 while maintaining the negative pressure atmosphere within the connecting chamber 15. (Rotational drive section)

[0116] The rotation drive section 33 is a drive mechanism that rotates the rotating shaft 32 and functions as a control unit that controls the rotation of the rotating film trap 36. For example, the rotation speed or the like of the rotating film trap 36 is controlled as needed by the rotation drive section 33. Furthermore, the rotation drive section 33 is fixed to the outside of the detachable member 31 by a fixed member not shown in the figure, so the rotation drive section 33 itself does not rotate with respect to the detachable member 31.

[0117] The rotation drive section 33 includes the motor 40 and a cooling mechanism, the illustration of which is omitted.

[0118] The motor 40 is connected to the rotating shaft 32 and rotates the rotating shaft 32 around its central axis. Therefore, the rotating shaft 32 of the motor 40 can be regarded as the rotating shaft of the rotating film trap 36. For example, an electric motor is used as the motor 40, in which the rotating shaft 32 is directly connected to a rotor or the like. However, a speed-changing mechanism, such as a gear, may be provided between the rotor and the rotating shaft 32.

[0119] The rotating film trap 36 is rotated by the motor 40. In this way, the plurality of rotating films F collide with the contaminants DB emerging from the plasma P to capture them. This prevents the contaminants DB originating from the plasma P from entering the application device 110.

[0120] The cooling mechanism cools the rotating film trap, the rotating shaft 32 and the motor 40.

[0121] In this embodiment, a cooling mechanism is provided that uses a coolant such as cooling water supplied from a water cooling pipe 41. A water inlet 42, to which cooling water is supplied from the water cooling pipe 41, and a water outlet 43 for returning the cooling water to the water cooling pipe 41 are provided outside the rotation drive section 33. The water inlet 42 and the water outlet 43 are connected to the cooling mechanism. Furthermore, a coupling or the like is used to connect the water cooling pipe 41 and the water inlet 42 (water outlet 43). This facilitates the detachment of the water cooling pipe 41.

[0122] For example, the rotating film trap 36 becomes hot due to the radiation of the plasma P. Therefore, to prevent overheating of the rotating film trap 36, a cooling mechanism is provided that cools the rotating shaft 32. As such a cooling mechanism, the rotating shaft 32 is made hollow, for example, to form a circulation channel for a coolant such as cooling water. Passing cooling water supplied from the water-cooling line 41 through this circulation channel enables cooling of the rotating shaft 32 and the rotating film trap 36 connected thereto. Furthermore, since the motor 40 also generates heat during rotation, the heat can be dissipated around the motor 40 through a pipe that passes cooling water.

[0123] In this way, in the contaminant trap unit 30 according to this embodiment, the motor 40 is connected to the outside of the detachable member 31, the rotating shaft 32 passes through the detachable member 31, and the central support post 37 (rotating member) of the rotating film trap is connected to the rotating shaft 32 inside the detachable member 31.

[0124] Such a configuration eliminates the need to dispose the rotation drive section 33 inside the chamber, allowing for a reduction in the size of the connecting chamber 15. Furthermore, the path of the EUV light from the plasma P to the outlet 16 can be shortened, thereby suppressing the broadening of the beam diameter of the EUV light. Accordingly, it is possible to configure a compact optical system provided in the application device 110.

[0125] Fig. 3 schematically shows a state in which the impurity trap unit 30 is detached from the connection chamber 15 (chamber main body 1). When the impurity trap unit 30 is detached, the operation of the EUV light source device 100 is stopped, and then the interior of the connection chamber 15 is returned to atmospheric pressure. Subsequently, the screws and the like securing the detachable member 31 are removed, and the detachable member 31 is detached from the connection chamber 15. At this time, the rotating film trap 36 is also detached together with the detachable member 31.

[0126] In this way, the impurity trap unit 30 is configured so that the film trap FT is integrally formed with the detachable member 31, which is a lid of the connecting chamber 15 serving as the chamber main body 1, and can be removed from the side surface of the vacuum housing. In this way, it is possible to easily remove the film trap FT arranged in the connecting chamber 15, for example, without removing the members constituting the light source section 2 (discharge electrodes EA and EB, containers CA and CB, etc.). Since the light source section 2 does not need to be disassembled, it is also unnecessary to adjust the optical axis of the EUV light, etc. As a result, the processing time for maintenance can be satisfactorily shortened, and the operating rate of the EUV light source device 100 can be improved. [Configuration example of a reinforced connection between the detachable element and the rotation drive section]

[0127] Fig. 6 is a schematic view showing another configuration example of the impurity trap unit.

[0128] One in Fig. 6 comprises a detachable member 51, a rotating film trap 56, a rotating shaft 52, a rotating drive section 53, and a reinforcing member 54. The contaminant trap unit 50 differs from the one shown in the Fig. 2 and Fig. 3 by the configuration of the connecting portion between the detachable member and the rotation drive portion. It should be noted that in Fig. 6 the guide mechanism is omitted.

[0129] The detachable member 51 includes a reinforcement portion 55 that reinforces the rigidity of the portion to which the rotation drive portion 53 is connected. The reinforcement portion 55 is a structural member that reinforces the rigidity of the detachable member 51 itself and is provided at the portion to which the rotation drive portion 53 is connected. In other words, the reinforcement portion 55 is a structure that suppresses deformation or the like of the portion to which the load of the rotation drive portion 53 acts.

[0130] In Fig. 6, a thick structure is provided as the reinforcement section 55, in which the thickness of the detachable element 51 is increased. Here, the central axis C0 of the rotating film trap 56 (rotating shaft 52) ​​is arranged at an inclination relative to the horizontal plane. In this case, the rotation drive section 53 is also arranged at an inclination relative to the horizontal plane.

[0131] In such a case, an outer surface (connecting surface 51a) of the detachable member 51, to which the rotation drive section 53 is connected, is configured as an inclined surface orthogonal to the central axis C0. The connecting surface 51a is inclined such that the reinforcement portion 55 with an increased thickness is arranged between the inner surface of the detachable member 51 and the connecting surface 51a, as shown in Fig. 6. Note that the structure of the reinforcing portion 55 is not limited, and, for example, a rib structure may be provided on the inner surface of the detachable member 51 as the reinforcing portion 55.

[0132] The arrangement of the reinforcing portion 55 directly under the connecting surface 51a makes it possible to avoid a situation in which the detachable member 51 is deformed due to the load exerted by the rotation drive portion 53 on the connecting surface 51a.

[0133] In addition, it is also possible to stably fix the rotation drive section 53.

[0134] The reinforcement member 54 is a member configured as a separate member from the detachable member 51, and which secures the rotation drive portion 53 to the detachable member 51. The reinforcement member 54 is a structural member made of metal, for example, a material with higher rigidity than the detachable member 51. For example, when the detachable member 51 is made of aluminum, a stainless steel reinforcement member 54 is used. Note that the reinforcement member 54 and the detachable member 51 may be made of the same material.

[0135] The rotation drive section 53, which controls the rotation of the rotary shaft 52 of the rotary film trap 56, is connected to the rear side of the rotary shaft 52. A cooling mechanism is provided within the rotation drive section 53, which circulates cooling water to cool the heat of the rotary shaft 52, the rotary film trap 56, or the like. Therefore, in the rotation drive section 53, a casing housing the cooling mechanism is larger than the diameter of the rotary shaft 52. Therefore, the mounting of the casing of the rotation drive section 53 enables a more stable mounting of the rotation drive section 53 compared to a structure in which the rotary shaft 52 is mounted by a mechanical seal, as shown in FIG. Fig. 2 shown.

[0136] The reinforcement member 54 is arranged between the connecting surface 51a of the detachable member 51 and the rotation drive section 53 and serves as a seat for receiving the rotation drive section 53. The reinforcement member 54 includes a through hole 57 through which the rotary shaft 52 passes, and a recessed portion 58 into which the housing of the rotation drive section 53 can be fitted. The reinforcement member 54 is fixed to the connecting surface 51a of the detachable member 51 by screwing or the like, with the recessed portion 58 facing outward. Furthermore, the rotation drive section 53 is fixed to the reinforcement member 54 by screwing or the like while being fitted into the recessed portion 58 of the reinforcement member 54.

[0137] In this way, Fig. 6, the reinforcing member 54 is provided to be fixed to the detachable member 51 detachable from the connecting chamber 15, and the rotation drive portion 53 supporting the rotary shaft 52 is fixed by attaching to the reinforcing member 54.

[0138] In this way, Fig. 6, the reinforcement portion 55 provided in the detachable member 51 and the reinforcement member 54 configured separately from the detachable member 51 are used to reinforce the connection between the detachable member 51 and the rotation drive portion 53. Note that the configuration for reinforcing the connection between the detachable member 51 and the rotation drive portion 53 is not limited. For example, either the reinforcement portion 55 of the detachable member 51 or the reinforcement member 54 may be provided.

[0139] For example, no reinforcement member 54 may be provided. In this case, the reinforcement portion 55 (thick structure or the like) including the inclined connecting surface 51a is provided on the detachable member 51, and the rotation drive portion 53 is directly attached to the connecting surface 51a. Note that a recess or the like may be formed in the connecting surface 51a to accommodate the rotation drive portion 53.

[0140] In addition, for example, no reinforcement portion 55 (thick structure or the like) of the detachable element 51 may be provided. In this case, the detachable element 51 is, for example, like the one shown in Fig. 2, and the connecting surface 51a is a flat surface in the vertical direction. The reinforcing member 54 is configured to support the rotation drive portion 53 in the inclined state with respect to the connecting surface 51a provided along the vertical direction in the manner described above.

[0141] For example, in the contaminant trap unit 50, the rotating film trap 56 is mounted with a relatively large diameter or width. Fig. 6 schematically shows the rotary drive section 56 with a larger diameter than that shown in Fig. 2. If the size of the rotation drive section 56 is large, the rotation drive section 53 may be enlarged. Furthermore, the large size of the rotation drive section 56 may increase vibration during rotation and shaking of the device.

[0142] In contrast, in Fig. 6, the reinforcement member 54 for supporting the housing of the rotary drive section 53 is provided on the reinforcement section 55 with increased rigidity of the detachable member 51. The section (housing of the rotary drive section 53) in which the cooling mechanism or the like for the stable operation of the rotary film trap 56 is housed can thus be kept mechanically stable. Consequently, even when using a large-sized rotary film trap 56, vibrations and shocks of the device can be suppressed for stable operation.

[0143] Note that the Fig. 6 is also effective when using a relatively small rotating film trap. [Configuration example with fixed foil trap]

[0144] Fig. Figure 7 is a schematic view showing another configuration example of the contaminant trap unit. A contaminant trap unit 60 is equipped with a fixed film trap in addition to the rotating film trap.

[0145] The Fig. 7 comprises a detachable member 61, a rotating film trap 66, a rotating shaft 62, a rotating drive section 63, a reinforcing member 64, a fixed film trap 67, and a gas introduction tube 69. The detachable member 61, the rotating shaft 62, the rotating drive section 63, and the reinforcing member 64 are similar to the one shown in Fig. 6, the rotary shaft 52, the rotation drive section 53, and the reinforcing member 54. In addition, the Fig. 2 shown rotating film trap 36 is used as rotating film trap 66, but the one shown in Fig. 6 shown rotating film trap 56 having a relatively large size can also be used.

[0146] The fixed foil trap 67 is a foil trap FT to which a plurality of foils F are attached.

[0147] The fixed film trap 67 is provided between the rotating film trap 66 and the outlet 16 on the path of the EUV light traveling from the plasma P to the outlet 16 of the connecting chamber 15 (chamber main body 1). In other words, the fixed film trap 67 is arranged downstream of the rotating film trap 66 and traps impurities DB that have passed through the rotating film trap 66.

[0148] Furthermore, the fixed film trap 67 is arranged with respect to the central path along which a flow of light rays of the EUV light to be extracted from the outlet 16 (EUV extraction light) passes. The central path is, for example, a path connecting the emission point of the plasma P and the center of the outlet 16. The fixed film trap 67 is connected to the detachable member 61 via a holding portion (not shown) so as to intersect the central path, while the detachable member 61 is fixed to the connection chamber 15. The specific configuration of the holding portion will be described later.

[0149] The gas introduction tube 69 penetrates the detachable member 61 and introduces a transparent gas that transmits EUV light into the fixed film trap 67. One end of the gas introduction tube 69 is arranged to protrude from the outside of the detachable member 61 and serves as a gas introduction port. Furthermore, another end of the gas introduction tube 69 is connected to the fixed film trap 67. The transparent gas supplied to the fixed film trap 67 is preferably a gas with high transmittance to EUV light, and for example, a rare gas such as helium (He), argon (Ar), or hydrogen (H2) is used.

[0150] Fig. 8 is a schematic cross-sectional view showing a configuration example of the fixed film trap. Fig. 9 is a schematic front view showing a configuration example of the fixed film trap. Fig. Figure 8 is a view of the fixed foil trap 67 along the central path of the EUV light. Fig. 9 a view of the fixed foil trap 67 from the central beam path direction of the EUV light.

[0151] As in the Fig. 8 and Fig. 9, the fixed film trap 67 includes a plurality of films F and a fixed frame 68 that fixes the plurality of films F. In this embodiment, the fixed frame 68 corresponds to a fixed member.

[0152] As in Fig. As shown in Figure 9, the plurality of sheets F are arranged at regular intervals as viewed from the central path direction of the EUV light. Furthermore, the fixed frame 68 has, for example, a rectangular shape when viewed from the front.

[0153] It should be noted that the outer shape of the fixed frame 68 can have any shape. In addition, as shown in Fig. 8, the plurality of foils F are arranged radially so that they extend in the light beam direction of the EUV light in cross section along the central path.

[0154] The plurality of foils F of the fixed foil trap 67 serves to divide the space in which the fixed foil trap 67 is arranged into finer sections in order to reduce the conductivity of these sections and to increase the pressure locally.

[0155] Additionally, the fixed film trap 67 is supplied with a transparent gas via the gas introduction tube 69. This makes it possible to increase the pressure in the fixed film trap 67. In other words, in conjunction with the connecting chamber 15, gas is localized in the fixed film trap 67 to establish a relatively high pressure range.

[0156] The high-speed contaminants DB not captured by the rotating film trap 66 decrease their speed because the probability of collision with the gas in the area of ​​increased pressure in the stationary film trap 67 increases. Furthermore, the collision with the gas also changes the direction of movement of the contaminants DB. The stationary film trap 67 captures the contaminants DB, whose speed has been reduced and whose direction of travel has thus been changed, by means of the films F or the fixed frame 68.

[0157] The rotating film trap 66 and the fixed film trap 67 are provided as described above so that the contaminants DB can be satisfactorily trapped. Furthermore, in the contaminant trap unit 60, both the rotating film trap 66 and the fixed film trap 67 are connected to the detachable member 61. This makes it possible to remove both the rotating film trap 66 and the fixed film trap 67 by detaching the detachable member 61. Such a configuration makes it possible to shorten maintenance time, for example, by replacing the contaminant trap unit 60 with a new one prepared in advance. [Foil trap cover]

[0158] Fig. 10 is a schematic view showing a configuration example of a contaminant trap unit with a film trap cover. Fig. 10 has a configuration in which a foil trap cover 71 for the in Fig. 7 shown impurity trap unit 60 is provided. Note that in Fig. 7 the rotation drive section and the application device are omitted.

[0159] The film trap cover 71 encloses the outer peripheral area of ​​the rotating film trap 66 and collects the contaminants DB scattered by the rotating film trap 66. By providing the film trap cover 71, the contaminants DB collected by the rotating film trap 66 can be prevented from being scattered into the interior of the connecting chamber 15.

[0160] The film trap cover 71 has an entrance opening KI and an exit opening KO. The entrance opening KI is provided at a location where the EUV light entering the rotating film trap 66 is not blocked. The exit opening KO is provided at a location where the EUV light that has entered the fixed film trap 67 through the entrance opening KI and the rotating film trap 66 is not blocked.

[0161] At least a portion of the impurities DB captured by the rotating film trap 66 moves radially on the films F of the rotating film trap 66 due to centrifugal force, detaches from the end portions of the films F, and adheres to the inner surface of the film trap cover 71. The film trap cover 71 is heated by a heating device (cover heating portion) not shown in the figure or by the radiation accompanying the EUV light radiation. The impurities DB adhering to the inner surface of the film trap cover 71 do not solidify and remain in a liquid phase due to the heating. The impurities DB adhering to the inner surface of the film trap cover 71 collect at the lower part of the film trap cover 71 due to gravity and are discharged to the outside of the lower part of the film trap cover 71 via a drain pipe 72 to become waste material.The contaminants DB that have become waste material are stored in a contaminant storage area not shown in the figure.

[0162] As in Fig. As shown in Figure 10, in the contaminant trap unit 70, the film trap cover 71 is connected to the detachable member 61. In other words, the film trap cover 71 is unified with the detachable member 61. For example, a tubular projection 73 surrounding the rotary shaft 62 is formed on the rear side of the film trap cover 71, and the tip of the projection 73 is connected to the detachable member 61. Of course, in addition to the projection 73, a portion connecting the film trap cover 71 and the detachable member 61 may also be provided. This makes it possible to detach the film trap cover 71 together with the detachable member 61.

[0163] In addition, in the example of Fig. 10, the fixed film trap 67 is connected to the film trap cover 71. Specifically, the fixed film trap 67 is attached to the back of the film trap cover 71 so as to cover the exit-side opening KO of the film trap cover 71. Thus, by using the film trap cover 71, the fixed film trap 67 can be easily unified. Furthermore, there is no need to provide a special holding section or the like for fixing the fixed film trap 67, which can reduce the cost of the device. [Heat shield element, detection sensor]

[0164] Fig. 11 is a schematic view showing a configuration example of a contaminant trap unit with a heat shield plate. Fig. The contaminant trap unit 80 shown in Fig. 11 has a configuration in which a heat shield element 81 and a detection sensor 82 are arranged at the Fig. 10 shown impurity trap unit 70.

[0165] The heat shield element 81 is connected to the detachable element 61 and arranged between the plasma P and the foil trap FT. In the Fig. In the example shown in Figure 11, the heat shield element 81 is arranged between the plasma P and the rotating foil trap FT. The heat shield element 81 is arranged near the plasma P and is therefore made of a high-melting material such as molybdenum or tungsten. The heat shield element 81 is provided to reduce the radiation of the plasma P onto the rotating foil trap 66 and prevent overheating of the rotating foil trap 66.

[0166] The heat shield element 81 is a plate-shaped element and is configured to cover the entire rotating film trap FT. Furthermore, the heat shield element 81 is provided with an opening KA and an opening KB through which the EUV light from the plasma P can pass.

[0167] The opening KA is an opening for extracting the EUV light to be emitted from the outlet 16 toward the application device 110. The opening KA is located at an eccentric position from the rotating shaft (central axis C0) of the rotating film trap 66. At this time, a portion of the EUV light emitted from the plasma P is discharged from the heat shield member 81 via the opening KA at a predetermined three-dimensional angle, an inclination angle, with respect to the rotating shaft of the rotating film trap 66. The rotating film trap 66 and the fixed film trap 67 are arranged so that the films F lie on the central path of a light beam flux of the EUV light (EUV extraction light) that has passed through the opening KA of the heat shield member 81.

[0168] The aperture KB is an aperture for extracting the EUV light emitted toward the detection sensor 82, which will be described later. The aperture KB is provided on a straight line from the emission point of the plasma P to the detection sensor 82. Fig. 11, the rotating film trap 66 and the film trap cover 71 are arranged between the plasma P and the detection sensor 82. Note that the film trap cover 71 is provided with an exit-side opening KO' through which the EUV light extracted via the opening KB can pass.

[0169] In Fig. 11, the upper end of the heat shield member 81 is bent and fixed to the inner surface of the detachable member 61. In other words, the heat shield member 81 is integrated with the detachable member 61. This makes it possible to remove the heat shield member 81 together with the detachable member 61, and to easily clean, replace, and the like the heat shield member 81.

[0170] The detection sensor 82 is a sensor connected to the detachable element 61 and detects the state of the plasma P. In this embodiment, the detachable element 61 is provided with a through-hole 83 for connecting the detection sensor 82. The detection sensor 82 is connected to the outside of the detachable element 61, so that the through-hole 83 is closed.

[0171] The EUV light that has passed through the above-described opening KB of the heat shield element 81, the rotating film trap 66, the exit-side opening KO' of the film trap cover 71, and the through-hole 83 of the detachable element 61 enters the detection sensor 82. Note that the detection sensor 82 can be connected to the inside of the detachable element 61 without the through-hole 83 being present.

[0172] For example, an optical sensor or the like that detects EUV light is used as the detection sensor 82. In this case, the EUV light intensity (emission intensity of the plasma P) can be detected by the detection sensor 82. Furthermore, a camera sensor or the like that images a state of the plasma P can be used as the detection sensor 82. In this case, the emission state of the plasma P can be observed by the detection sensor 82. Furthermore, the type of the detection sensor 82 is not limited, and any sensor that can detect a state of the plasma P (temperature, color, size, etc.) can be used.

[0173] In this way, the detection sensor 82 is connected to the detachable element 61 in Fig. 11. In other words, the detection sensor 82 is unified with the detachable member 61. This makes it possible to detach the detection sensor 82 together with the detachable member 61 and easily clean, replace, and the like the detection sensor 82.

[0174] As described above, in the impurity trap units 30, 50, 60, 70, and 80 according to this embodiment, at least one film trap FT including a plurality of films F that trap impurities from the plasma P is connected to a detachable member that covers the opening 17 of the communication chamber 15 serving as the chamber main body 1 and is attached to / detached from the communication chamber 15. In the attached state of the detachable member, the plurality of films F are arranged on the radiation path from the plasma P to the outlet. In addition, when the detachable member is detached, the film trap FT can also be detached together. This makes it possible to shorten the maintenance time for the film trap FT and thus make maintenance more efficient.

[0175] Generally, a light source device that emits EUV light is connected to an application device for utilizing the EUV light. The application device is equipped with a complex optical system to adjust the EUV light emitted by the light source device, and its optical axis is adjusted from the emission point of the plasma P. Furthermore, the application device is often a larger device than the light source device, and it is conceivable that the application device is coupled with another device. Since the light source device is located at the end of the system, it was necessary to disassemble the light source device once for maintenance of the impurity trap.

[0176] In addition, when disassembling the light source assembly, components such as the chamber lid, rotating electrodes, raw material containers, and the plate at the boundary of the impurity trap (heat shield plate, etc.) must be removed one by one from the end, and then the impurity trap can be removed. Therefore, accessing the impurity container during impurity trap maintenance required considerable labor and time.

[0177] In addition, as described above, the optical system of the application device is adjusted to the optical axis starting from the plasma emission point P. On the other hand, during maintenance involving disassembly of the light source device, the rotating electrode serving as the emission point is removed. Therefore, after the impurity trap maintenance is completed and the light source device is reassembled, further adjustment to align the optical axes is required. As a result, there is a possibility of lengthening the downtime of the light source device and the application device, and reducing the utilization efficiency of the devices.

[0178] In the contaminant trap unit according to this embodiment, the film trap FT is connected to the detachable member mounted on the opening 17 of the connecting chamber 15 serving as the chamber main body 1. In other words, a lid (detachable member) is provided on a part of the container (connecting chamber 15) in which the film trap FT is located, and the lid and the film trap FT are integrated.

[0179] In such a configuration, when removing the film trap FT, only the detachable element needs to be removed from the connecting chamber 15, and there is no need to disassemble the light source section 2 and the like. This allows for easy attachment or removal of the film trap FT. Furthermore, the time required for maintenance of the film trap FT can be significantly reduced.

[0180] Furthermore, in this embodiment, the elements integrated with the impurity trap unit do not include an optical element that changes the optical path of the EUV light. This makes it possible to perform maintenance in a state where the optical axis reaching the optical system of the application device 110 from the emission point (light generation location) of the plasma P is substantially maintained. This eliminates the need for drastic optical axis adjustment, such as that required when detaching the discharge electrode, and makes it possible to adjust the optical axis relatively easily. As a result, the downtime of the light source device and the application device is shortened, and the utilization efficiency of the devices can be improved.

[0181] Furthermore, the rotating film trap, the fixed film trap, the film trap cover, the heat shield element, the detection sensor, and the like can be integrated into the contaminant trap unit. This makes it possible to perform maintenance on a plurality of unified elements simultaneously, saving time and effort for maintenance. This enables efficient maintenance of the various elements provided in the connecting chamber 15. <Zweite Ausführungsform>

[0182] An EUV light source device according to a second embodiment of the present invention will be described. In the following description, the description will be omitted or simplified for parts similar to the configurations and actions in the EUV light source device 100 described in the above embodiment.

[0183] Fig. 12 is a schematic cross-sectional view showing a configuration example of an EUV light source device with a contaminant trap unit according to a second embodiment. An EUV light source device 200 includes a chamber main body 201, a light source unit 202, and a contaminant trap unit 230. In this embodiment, a configuration in which a condensing mirror 250, which condenses EUV light, is integrated with the contaminant trap unit 230 will be described.

[0184] The chamber main body 201 comprises an outlet 90 for EUV light, a first opening 91, a second opening 92 and a vacuum outlet opening 93. The Fig. The chamber main body 201 shown in Fig. 12 has a structure in which a conical casing is connected to one end of a tubular casing.

[0185] The outlet 90 is provided at the tip of the conical housing. Furthermore, the first opening 91 is provided at the end portion of the tubular housing on the opposite side of the outlet 90. Furthermore, the second opening 92 and the vacuum outlet opening 93 are located on the side surface of the tubular housing.

[0186] Outlet 90 is an optical window for introducing EUV light from plasma P into an application device not shown in the figure. Outlet 90 is typically a through-hole, but a transparent element such as an optical filter may also be provided.

[0187] The first opening 91 is an opening to which the light source unit 202 is connected.

[0188] The second opening 92 is an opening to which the contaminant trap unit 230 is connected. In Fig. 12, the second opening 92 is formed on the upper side of the figure.

[0189] The vacuum outlet port 93 is connected to a vacuum pump 95, which empties the chamber main body 201. In Fig. 12, the vacuum outlet port 93 is formed on the lower side of the figure.

[0190] The light source unit 202 is obtained by assembling a mechanism for generating plasma P with a base 96 which functions as a cover of the first opening 91.

[0191] The light source unit 202 is configured as a device that generates plasma P, for example, by the LDP method, similar to that shown in Fig. 1. In this case, a pair of discharge electrodes are arranged opposite each other, and a pair of containers for supplying a plasma raw material to the respective discharge electrodes are fixed to the base 96. Furthermore, the chamber main body 201 is provided with a transparent window (not shown) through which an energy beam (e.g., a laser beam) can be introduced.

[0192] The energy beam is applied to a discharge electrode in a discharge zone where the discharge electrodes face each other. Irradiation with the energy beam feeds a gas-phase plasma raw material into the discharge zone.

[0193] When current is supplied to each of the discharge electrodes, the plasma raw material is heated and excited by discharge, and a plasma P is generated.

[0194] It should be noted that instead of the light source unit 202 of the LDP method, a light source unit 202 that generates plasma P by another method such as the LPP method may be used.

[0195] The Fig. The contaminant trap unit 230 shown in Figure 12 is obtained by assembling a film trap FT and the condensation mirror 250. The contaminant trap unit 230 includes a detachable member 231, a rotating film trap 236 as the film trap FT, a rotating shaft 232, a rotating drive section 233, a water cooling tube 234, an RFF support section 237, a film trap cover 240, and the condensation mirror 250.

[0196] The detachable member 231 is a member that covers the second opening 92 and is configured to be attached to / detached from the chamber main body 201, and functions as a lid for closing the second opening 92. The rotating film trap 236, the condensation mirror 250, and the like, which constitute the contaminant trap unit 230, are directly or indirectly connected to the detachable member 231 to form a unit.

[0197] In the example of Fig. 12, in which the detachable element 231 is connected to the chamber main body 201, the rotating film trap 236 and the condensing mirror 250 are arranged in the specified order on the way from the emission point of the plasma P to the outlet 90.

[0198] The rotating film trap 236 includes a plurality of radially arranged films F and is connected to the rotation drive part 233 via the rotating shaft 232. The water cooling pipe 234, which penetrates the detachable member 231, is connected to the rotation drive section 233, and cooling water or the like is supplied thereto. Furthermore, a power cable or the like is wired for the rotation drive section 233. In this embodiment, in which the contaminant trap unit 230 is attached to the chamber main body 201, the rotating film trap 236 and its drive mechanism (rotating shaft 232 and rotation drive section 233) are all housed in the chamber main body 201.

[0199] The RFF support section 237 is a member attached to the detachable member 231 and supports the RFF (rotating film trap 236) with respect to the detachable member 231. Specifically, the RFF support section 237 is configured to support the rotation drive section 233. Furthermore, the rotating shaft 232 connected to the rotating film trap 236 is rotatably supported by a bearing mechanism, such as a bearing (not shown in the figure), incorporated into the rotation drive section 233. Thus, the RFF support section 237 supports the rotating film trap 236 via the rotation drive section 233 and the rotating shaft 232.

[0200] As in Fig. 12, the RFF support portion 237 is, for example, a plate-shaped member as a whole and includes a through-hole 238 for passing the rotary shaft 232 and an opening KC for transmitting EUV light therethrough.

[0201] Furthermore, the RFF support portion 237 is disposed between the rotating film trap 236 and the rotation drive portion 233, and one end surface of the rotation drive portion 233 at the front is fixed to the RFF support portion 237. At this time, the RFF support portion 237 and the rotation drive portion 233 are fixed to each other so that the axis of the rotary shaft 232 is aligned with the central axis C1 of the condensing mirror 250 to be described later.

[0202] Fig. 13 is a schematic plan view showing a configuration example of the RFF support portion 237. The RFF support portion 237 includes a central portion 237a, a peripheral portion 237b, and a plurality of spokes 237c.

[0203] The central portion 237a is a portion provided at the center of the RFF support portion 237 and a portion to which the rotation drive portion 233 is attached. The central portion 237a is provided with a through hole 238 whose inner diameter is larger than the diameter of the rotary shaft 232. The peripheral portion 237b is provided to surround the central portion 237a at a certain distance from the central portion 237a. The peripheral portion 237b is, for example, a portion connected to the detachable member 231 or the film trap cover 240. The plurality of spokes 237c are long members that connect the central portion 237a and the peripheral portion 237b. A cavity surrounded by the central portion 237a, the peripheral portion 237b, and each spoke 237c forms the opening KC for the passage of the EUV light.

[0204] In the Fig. In the example shown in Figure 13, six spokes 237c are arranged at 60-degree intervals, and six openings KC are formed between the central portion 237a and the peripheral portion 237b. These openings KC are mainly located in the optical path of the EUV light that has passed through the rotating film trap 236.

[0205] In addition, the number of spokes 237c and the openings KC as well as their shape are not limited.

[0206] In addition, in the Fig. 13, the outer periphery of the RFF support portion 237 (peripheral portion 237b) has a cylindrical surface, but in order to be attached to the detachable member 231, for example, the outer periphery may be partially flat.

[0207] Back to Fig. 12: The film trap cover 240 encloses the outer peripheral area of ​​the rotating film trap 236 and collects the impurities DB scattered by the rotating film trap 236. The film trap cover 240 is a tubular member that accommodates the rotating film trap 236. An entrance-side opening KI, into which the EUV light enters, is located at the front of the film trap cover 240 (on the side facing the plasma P), and the RFF support portion 237 is connected to the back of the film trap cover 240. In the Fig. In the example shown in Figure 12, the RFF support portion 237 covers the back of the foil trap cover 240 and functions as part of the cover.

[0208] For example, the RFF support portion 237 and the film trap cover 240 are each attached to the detachable member 231 while being attached to each other. Alternatively, for example, one of the RFF support portion 237 or the film trap cover 240 may be attached to the detachable member 231, and the other may be attached to the one attached to the detachable member 231. Alternatively, the RFF support portion 237 and the film trap cover 240 may not be attached to each other and may be attached individually to the detachable member 231. In either case, the rotation drive portion 233 is supported by the RFF support portion 237.

[0209] Note that, in addition to the RFF support portion 237, the water cooling pipe 234 connected to the rear side of the rotation drive portion 233 may be configured as a member supporting the rotation drive portion 233. Furthermore, the water cooling pipe 234 may be arranged along the RFF support portion 237 and connected to the front side of the rotation drive portion 233.

[0210] Fig. 14 is a schematic perspective view showing a configuration example of the condensing mirror.

[0211] The condensing mirror 250 is connected to the detachable element 231 and condenses the EUV light from the plasma P.

[0212] The condensing mirror 250 includes a reflective surface 251 that reflects the EUV light and a support 252 to which the reflective surface 251 is attached.

[0213] In this embodiment, the reflecting surface 251 is formed on an inner peripheral surface of the tubular support 252. Therefore, the condensing mirror 250 is a tubular reflecting mirror. As shown in Fig. As shown in Figure 14, the condenser mirror 250 is a grazing incidence mirror, and the reflective surface 251 is formed from a single-layer film. The reflective surface 251 is formed, for example, by coating the inner peripheral surface of the substrate 252 with a single-layer film of ruthenium.

[0214] Hereinafter, the side on which the EUV light enters is referred to as the front side of the condensing mirror 250, and the side on which the EUV light exits is referred to as the back side of the condensing mirror 250.

[0215] The reflection surface 251 is, for example, a curved surface that is rotationally symmetrical about the central axis C1. The shape of the reflection surface 251 (the shape of the inner peripheral surface of the support 252) is designed such that the light is focused from an emission point 253 on the central axis C1, which lies on the front side of the condenser mirror 250, to a focal point 254 on the central axis C1, which lies on the back side of the condenser mirror. The emission point 253 of the condenser mirror 250 corresponds to the emission point of the plasma P. Furthermore, the focal point 254 of the condenser mirror 250 corresponds, for example, to the center position of the outlet 90.

[0216] It should be noted that the reflective surface 251 is not limited to the rotationally symmetric configuration, and a freeform surface or the like designed by optical simulation may also be used.

[0217] As in Fig. As shown in Figure 12, the holder 252 of the condensing mirror 250 is fixed to the detachable member 231 such that the emission point of the plasma P and the emission point 253 set for the condensing mirror 250 coincide with each other, and the center position of the outlet 90 and the focal point 254 set for the condensing mirror 250 coincide with each other, with the detachable member 231 being connected to the chamber main body 201. Thus, the EUV light emitted from the plasma P, which has passed through the rotating film trap 236 and entered the front side of the condensing mirror 250, is converged at the outlet 90.

[0218] Furthermore, the condensation mirror 250 is connected to the rotating foil trap 236, which allows the condensation mirror 250 to be removed together with the detachable element 231. This makes it possible to easily clean, replace, or otherwise service the condensation mirror 250.

[0219] Furthermore, the rotating film trap 236, i.e., the film trap FT, is arranged between the plasma P and the condenser mirror 250. This allows for the capture of impurities DB escaping from the plasma P before they enter the condenser mirror 250, thus preventing the impurities DB from colliding with and depositing on the reflective surface 251. Furthermore, when the detachable element 231 is removed, the rotating film trap 236 is also removed, allowing for easy maintenance of the rotating film trap 236.

[0220] Note that the condensation mirror 250 is not connected to the RFF support section 237 and the film trap cover 240, and is attached to the detachable member 231 independently of the RFF support section 237 and the film trap cover 240. In this way, for example, the vibration generated by the rotation of the rotating film trap 236 can be prevented from being directly transmitted to the condensation mirror 250. In this way, vibrations of the condensation mirror 250 can be suppressed.

[0221] Furthermore, in this configuration with the tubular condensing mirror 250, the EUV light that has passed through the entire circumference of the rotating film trap 236 is condensed. This makes it possible to increase the amount of EUV light compared to the case where only the EUV light that passes through a part of the angular range of the rotating film trap is extracted, as described, for example, with reference to Fig. 2 and the like.

[0222] It should be noted that the reflective surface 251 in the Fig. 12 and Fig. 14 is a single layer, but a multi-layer reflective surface 251 can be configured to surround, for example, the central axis C1. This can further improve the light condensation efficiency of the EUV light. [Rotating film trap and fixed film trap]

[0223] Fig. Figure 15 is a schematic view showing another configuration example of the impurity trap unit including the condensation mirror. Fig. The impurity trap unit 230a shown in Figure 15 is obtained by combining two types of film traps FT (rotating film trap 236 and fixed film trap 245) with the condenser mirror 250. The impurity trap unit 230a has a configuration in which the fixed film trap 245 is added to the Fig. 12 shown contaminant trap unit 230.

[0224] The fixed film trap 245 includes an inner ring 246 arranged around a predetermined axis and an outer ring 247 arranged to surround the inner ring 246. In the tubular inner region located between the inner ring 246 and the outer ring 247, a plurality of films F are arranged radially around the predetermined axis. At this time, each film F is located in a plane including the predetermined axis. Thus, the tubular fixed film trap 245 is used in this embodiment.

[0225] The fixed film trap 245 is arranged on the back side of the rotating film trap 236, with the RFF support portion 237 interposed therebetween, so that the predetermined axis and the axis of the rotating shaft 232 are aligned. Furthermore, the inner ring 246 and the outer ring 247 of the fixed film trap 245 are configured so as not to block the optical path of the EUV light emitted from the opening KC arranged in the RFF support portion 237. Furthermore, a gas introduction tube 248 penetrating the detachable member 231 is connected to the inner portion of the fixed film trap 245, and a transparent gas with high transmittance to the EUV light is supplied.

[0226] For example, the high-speed contaminants DB that were not captured by the rotating film trap 236 collide with the gas in the region of increased pressure in the stationary film trap 245. The contaminants DB whose speed has been reduced and whose direction of movement has been changed by the collision with the gas are captured by the films F, the inner ring 246, and the outer ring 247.

[0227] The rotating film trap 236 and the fixed film trap 245 are designed so that the contaminants DB can be collected satisfactorily.

[0228] The film trap cover 240 provided on the contaminant trap unit 230a encloses both the rotating film trap 236 and the fixed film trap 245. In other words, the rotating film trap 236 and the fixed film trap 245, which are arranged with the RFF support portion 237 therebetween, are housed in the film trap cover 240.

[0229] Similar to Fig. 12, an entrance-side opening KI is provided on the front side of the film trap cover 240, into which the EUV light enters. Furthermore, an insertion hole 241 is formed on the back side of the film trap cover 240. The insertion hole 241 is surrounded by an annular protrusion protruding toward the RFF support portion 237. The insertion hole 241 is a hole in which the rotary shaft 232 and the rotation drive portion 233 are arranged, and the tip of the insertion hole 241 (protrusion) is connected to the RFF support portion 237. Furthermore, an exit-side opening KO is provided around the insertion hole 241, from which the EUV light that has passed through the fixed film trap 245 exits.

[0230] Thus, the impurities DB trapped by the fixed film trap 245 flow into the film trap cover 240 and are trapped by the film trap cover 240. In this way, the impurities DB trapped by the fixed film trap 245 can be prevented from adhering to the rotary shaft 232 or the like.

[0231] In the Fig. In the example shown in Figure 15, the fixed film trap 245 is attached to the RFF support portion 237, but the fixed film trap 245 may also be attached to the film trap cover 240, for example.

[0232] Furthermore, the RFF support portion 237 and the film trap cover 240 may be attached to the detachable member 231 while being attached to each other, or one of them may be attached to the other, which is attached to the detachable member 231. Furthermore, the RFF support portion 237 and the film trap cover 240 may be attached individually to the detachable member 231.

[0233] Note that the condensation mirror 250 is not connected to the film trap cover 240, but is attached to the detachable element 231 independently of the trap cover 240. This reduces the likelihood of vibrations from the rotating film trap 236 being transmitted to the condensation mirror 250. [Position adjustment mechanism for]

[0234] Fig. 16 is a schematic view showing another configuration example of the impurity trap unit including the condensation mirror. Fig. The impurity trap unit 230b shown in Fig. 16 has a configuration in which the Fig. 15 is provided with a position adjustment mechanism 262.

[0235] The contaminant trap unit 230b comprises an intermediate member 261, a position adjustment mechanism 262 and an enlargeable cover 263. It should be noted that the Fig. 12 and Fig. 15 described representation of the water cooling line and the gas supply line in Fig. 16 is omitted.

[0236] The intermediate member 261 is formed as an independent member from the detachable member 231 and integrally supports the rotating film trap 236, the fixed film trap 245, and the condensing mirror 250. Specifically, the rotating film trap 236 and the fixed film trap 245 are attached to the intermediate member 261 via at least one of the RFF support portions 237 or the film trap cover 240. Furthermore, the bracket 252 of the condensing mirror 250 is attached to the intermediate member 261 independently of the RFF support portion 237 and the film trap cover 240.

[0237] The position adjustment mechanism 262 is a mechanism for adjusting the arrangement of the condensing mirror 250. Here, the arrangement of the condensing mirror 250 includes the position and attitude of the condensing mirror 250. The position of the condensing mirror 250 is, for example, an X coordinate, a Y coordinate, and a Z coordinate of the reference position (e.g., position of the center of gravity) of the condensing mirror 250. In addition, the attitude of the condensing mirror 250 is a roll angle, a pitch angle, and a yaw angle of the condensing mirror 250. If the condensing mirror 250 is rotationally symmetric, the roll angle does not need to be adjusted.

[0238] The position adjustment mechanism 262 is configured to be capable of adjusting these parameters.

[0239] The position adjustment mechanism 262 includes a drive section 264 and an adjustment shaft 265.

[0240] The drive section 264 is connected to the adjustment shaft 265 and drives the adjustment shaft 265. The drive section 264 is configured, for example, so that the position of the adjustment shaft 265 is adjustable in the three mutually orthogonal axial directions.

[0241] Furthermore, the drive section 264 can be configured, for example, to adjust the position, such as rotation or inclination, of the adjustment shaft 265. A servo motor or the like is used as the drive section 264, but a mechanism or the like that manually adjusts the position or attitude of the adjustment shaft 265 can also be used.

[0242] In Fig. 16, two pairs of the drive section 264 and the adjustment shaft 265 are arranged, but the required number of drive sections 264 and adjustment shafts 265 can be arranged so that the arrangement of the condensing mirror 250 can be adjusted.

[0243] Furthermore, the drive section 264 is connected to the outside of the detachable member 231, and the adjustment shaft 265 is connected to the intermediate member 261 inside the detachable member 231 through a through hole 267 provided in the detachable member 231. This configuration makes it possible to use, for example, a servo motor or the like operating in the atmosphere as the drive section 264 as it is, and to reduce the cost of the device.

[0244] Note that the through hole 267 for passing the adjustment shaft 265 is formed larger than the adjustment shaft 265 so that the position or posture of the adjustment shaft 265 can be changed. In this regard, the adjustment shaft 265 is provided with the enlargeable cover 263 to close the gap between the through hole 267 and the adjustment shaft 265.

[0245] The expandable cover 263 is a tubular member with an open end. The side surface of the expandable cover 263 is provided with, for example, a bellows. The open end of the expandable cover 263 is connected to the inside of the detachable member 231 so as to surround the through-hole 267 through which the adjusting shaft 265 passes. Furthermore, the adjusting shaft 265 penetrates the lower part of the expandable cover 263 to connect to the intermediate member 261. Note that the expandable cover 263 is connected to the detachable member 231 and the adjusting shaft 265 without leakage. This makes it possible to adjust the position of the condensing mirror 250 by sliding the adjusting shaft 265 while maintaining the negative pressure atmosphere of the chamber main body 201.

[0246] The condensing mirror 250 is an optical element that adjusts the optical path of the EUV light. For example, if the position or posture of the condensing mirror 250 shifts when the contaminant trap unit 230b is attached / detached, the optical path of the EUV light from the light source unit 202 to the application device may change, and the focal point or the like may shift.

[0247] Even in such a case, in the impurity trap unit 230b, the position or posture of the condensing mirror 250 can be adjusted using the position adjustment mechanism 262. This makes it possible to easily adjust the optical path of the EUV light or the like and complete maintenance in a short time even if the condensing mirror 250 is unified.

[0248] Note that in Fig. 16, the drive portion 264 of the position adjustment mechanism 262 is disposed outside the detachable member 231. The drive portion 264 is not limited to this and may also be disposed inside the detachable member 231.

[0249] In this case, there is no need to provide the through hole 267 for passing the adjusting shaft 265, the enlargeable cover 263 for preventing leakage, and the like in the detachable member 231, so that the configuration of the device can be simplified. [Vibration isolation mechanism]

[0250] Fig. Figure 17 is a schematic view showing another configuration example of the impurity trap unit including the condensation mirror. Fig. The impurity trap unit 230c shown in Fig. 17 has a configuration in which the Fig. 16 is equipped with a vibration isolation mechanism 270.

[0251] The vibration isolation mechanism 270 is a mechanism that suppresses vibrations transmitted to the chamber main body 201. In other words, the vibration isolation mechanism 270 prevents vibrations of the impurity trap unit 230c, including the condensation mirror 250, from being transmitted to the chamber main body 201.

[0252] The vibration transmitted to the chamber main body 201 is mainly vibration generated when the rotating film trap 236, with which the contaminant trap unit 230c is equipped, and its drive mechanism (rotating shaft 232 and rotation drive part 233) operate. The light source unit 202, which generates plasma P, is connected to the chamber main body 201. Therefore, when the chamber main body 201 vibrates, it can be seen that the light changes position in the application device located downstream of the focal point 254. In addition, the vibration itself may be transmitted to the application device and cause a problem. The vibration isolation mechanism 270 is a mechanism that makes it difficult for such vibrations to be transmitted to the chamber main body 201 and reduces the vibration of the contaminant trap unit 230c itself.

[0253] The vibration isolation mechanism 270 is a mechanism including a vibration isolation portion 271 and a vibration sensor (illustration of which is omitted), and performs active vibration isolation by operating the vibration isolation portion 271 in response to the output of the vibration sensor.

[0254] The vibration isolation section 271 is an element that expands and contracts to reduce vibrations, and, for example, a linear actuator consisting of a piezoelectric element or a stepping motor is used. Fig. In the example shown in Figure 17, the vibration isolation portion 271 is provided for each pair of the drive portion 264 and the adjustment shaft 265. Specifically, the vibration isolation portion 271 is disposed between the drive portion 264 and the adjustment shaft 265. In other words, the vibration isolation portion 271 functions as part of the adjustment shaft 265.

[0255] The vibration sensor is a sensor that detects the vibration generated by the operation of the rotating film trap 236 and is designed, for example, to detect the vibration of the intermediate element 261. A laser displacement sensor, an acceleration sensor, or the like is used as a vibration sensor, for example.

[0256] The vibration isolation portion 271 expands and contracts to cancel the vibration of the intermediate member 261 based on the output signal of the vibration sensor. The expansion and contraction of the vibration isolation portion 271 suppresses the vibration of the intermediate member 261 generated by the operation of the rotating film trap 236 or the like, and thus suppresses the vibration transmitted from the intermediate member 261 to the chamber main body 201. This enables the suppression of positional fluctuations of light or the like in the application device to which the EUV light is to be applied. Furthermore, vibrations transmitted from the chamber main body 201 to the application device are also suppressed, thereby preventing the occurrence of defects due to the vibration.Since the vibration of the intermediate member 261 is suppressed, the vibration of the condensing mirror 250 attached to the intermediate member 261 is also suppressed. This makes it possible to prevent deterioration of the EUV light condensing accuracy by the condensing mirror 250.

[0257] In the Fig. In the example shown in Figure 17, the vibration isolation section 271 is provided between the drive section 264 and the adjustment shaft 265. This makes it possible to use, for example, a linear actuator with a relatively long extension or retraction length that can provide sufficient vibration isolation performance. Note that the vibration isolation section 271 can also be provided at a different location.

[0258] For example, the vibration isolation portion 271 may be provided between the intermediate member 261 and the fixed member (RFF support portion 237 or film trap cover 240) of the rotating film trap 236.

[0259] Alternatively, the vibration isolation portion 271 may be provided between the intermediate member 261 and the condensing mirror 250. In other words, the vibration isolation portion 270 may be configured to suppress vibrations transmitted to the condensing mirror 250.

[0260] For example, EUV light condensation accuracy can be maintained at a high level.

[0261] Furthermore, the vibration isolation mechanism 270 can be configured to enable passive vibration isolation. In this case, a member or the like that functions as a damper to dampen vibrations is used as the vibration isolation portion 271. With passive vibration isolation, for example, the vibration isolation portion 271 can be configured inexpensively, and there is no need to provide a vibration sensor or the like. Therefore, the cost of the device can be reduced.

[0262] In Fig. 17, the configuration in which the vibration isolation mechanism 270 is provided on the contaminant trap unit 230c including the position adjustment mechanism 262 was described. The present invention is not limited to this, but the vibration isolation mechanism 270 may also be provided on a contaminant trap unit without the position adjustment mechanism 262, as shown in FIGS. Fig. 12 and Fig. 15. In this case, for example, the vibration isolation portion 271 is provided between the detachable member 231 and the fixed member (RFF support portion 237 or film trap cover 240) of the rotating film trap 236. Alternatively, the vibration isolation portion 271 may also be provided between the detachable member 231 and the capacitor mirror 250.

[0263] In the configuration where the condensing mirror 250 is unified in this way, the provision of the vibration isolation mechanism 270 enables the suppression of vibrations transmitted to the chamber main body 201 and / or the condensing mirror 250 (such as vibrations generated by the operation of the rotating film trap 236). This makes it possible to supply properly condensed EUV light to the application device. <Andere Ausführungsformen>

[0264] The present invention is not limited to the embodiments described above, and various other embodiments can be realized.

[0265] In the above-described embodiments, an EUV light source device that extracts EUV light from plasma P has been described. The present invention is not limited thereto, but can be applied to a light source device that extracts X-rays and the like, which have shorter wavelengths than EUV light, from plasma P.

[0266] Furthermore, in the above-described embodiments, a light source device of the LDP method was mainly described, but the method for generating EUV light or radiation such as X-rays is not limited. For example, the present invention can be applied to a light source device of the LPP method. Furthermore, when impurities DB from plasma P are trapped in a device that generates plasma P, the efficiency of film trap maintenance can be improved by adopting the impurity trap unit according to the present invention.

[0267] In the present disclosure, words such as "substantially" and "approximately" are used appropriately to make the explanation easy to understand, but there is no clear distinction between the cases where these words are used and the cases where they are not used.

[0268] In other words, in the present disclosure, terms defining shape, size, positional relationship, state, and the like, such as “centered,” “equal,” “identical,” “orthogonal,” “parallel,” “symmetric,” and “cylindrical,” are concepts including “substantially centered,” “substantially equal,” “substantially identical,” “substantially orthogonal,” “substantially parallel,” “substantially symmetric,” “substantially cylindrical,” and the like.

[0269] The concepts also include terms with states within a given range (e.g., ±10%) with respect to, for example, “exactly centered,” “exactly equal,” “exactly identical,” “exactly orthogonal,” “exactly parallel,” “exactly symmetric,” and “exactly cylindrical.”

[0270] Therefore, even if words like "substantially" and "approximately" are not added, the terms may also include those expressed by adding "essentially," "approximately," and the like. Conversely, states expressed by adding "substantially," "approximately," and the like do not necessarily exclude their exact states.

[0271] In the present disclosure, expressions that use the term "than," such as "greater than A" and "less than A," are expressions that fully encompass concepts that include the case of being equal to A and concepts that do not include the case of being equal to A. For example, "greater than A" is not limited to the case where it does not include "equal to A"; however, it also includes "equal to or greater than A." Furthermore, "less than A" is not limited to "less than A"; it also includes "equal to or less than A."

[0272] In implementing the present technology, specific conditions and other conditions can be appropriately adopted from the concepts contained in “greater than A” and “less than A” to achieve the effects described above.

[0273] Among the characteristic portions according to the technology described above, at least two of the characteristic portions can also be combined. In other words, the various characteristic parts described in each embodiment can be optionally combined independently of the embodiments. Furthermore, the various effects described above are merely illustrative and not restrictive, and other effects can also be exerted. List of reference symbols F foil FT foil trap 1, 201 chamber main body 15 connecting chamber 16, 90 outlet 17 Opening 30, 50, 60, 70, 80, 230, 230a, 230b, 230c Contaminant trap unit 31, 51, 61, 231 detachable element 32,52,62,232 rotating shaft 33, 53, 63, 233 Rotary drive section 34 Guide mechanism 36, 56, 66, 236 Rotating film trap 54 Reinforcing element 55 reinforcement section 67, 245 Fixed foil trap 69,248 Gas inlet pipe 71, 240 foil trap cover 81 Heat shield element 82 detection sensor 92 second opening 100, 200 EUV light source device 250 condensation mirrors 262 Position adjustment mechanism 270 vibration isolation mechanism QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2017-219698

[0020]

Claims

[1] A contaminant trap unit mounted on an opening of a chamber main body including an outlet for radiation from plasma, the opening being different from the outlet, the contaminant trap unit comprising: a detachable member covering the opening and configured to be attached to and detached from the chamber main body, and at least one foil trap comprising a plurality of foils for trapping contaminants from the plasma and connected to the detachable member such that the plurality of foils are arranged on a path of radiation from the plasma to the outlet, the detachable member being attached to the chamber main body. [2] Contaminant trap unit according to claim 1, wherein the at least one foil trap comprises a rotating foil trap containing the plurality of foils and a rotating member radially supporting the plurality of foils, and the contaminant trap unit further comprises: a shaft section connected to the rotating element of the rotating foil trap, and a rotary drive section that rotates the shaft section. [3] Contaminant trap unit according to claim 2, wherein the rotation drive section is connected to an outer side of the detachable element, the shaft section penetrates the detachable element and the rotating element is connected to the shaft section within the detachable element. [4] The contaminant trap unit according to claim 3, further comprising a reinforcing member configured as a separate member from the detachable member and fixing the rotation drive portion to the detachable member. [5] The contaminant trap unit according to claim 3, wherein the detachable member has a reinforcing portion that reinforces the rigidity of a portion to which the rotation drive portion is connected. [6] Contaminant trap unit according to one of claims 2 to 5, wherein the at least one film trap comprises a fixed film trap having a plurality of films and a fixed member fixing the plurality of films. [7] Contaminant trap unit according to claim 6, further comprising a film trap cover connected to the detachable member, enclosing an outer peripheral portion of the rotating film trap and trapping the contaminants scattered by the rotating film trap, wherein the fixed foil trap is connected to the foil trap cover. [8] The contaminant trap unit according to claim 6, further comprising a gas introduction tube penetrating the detachable member and introducing a transparent gas into the fixed film trap, the transparent gas being permeable to the radiation. [9] The contaminant trap of claim 1, further comprising a condensing mirror connected to the detachable element and condensing the radiation from the plasma, wherein at least one foil trap is arranged between the plasma and the condensation mirror. [10] The contaminant trap unit of claim 9, further comprising a position adjustment mechanism that adjusts the arrangement of the condensation mirror. [11] The contaminant trap unit according to claim 9, further comprising a vibration isolation mechanism that suppresses vibrations transmitted to the chamber main body and / or the condensing mirror. [12] The contaminant trap unit according to claim 1, further comprising at least one of a heat shield member connected to the detachable member and disposed between the plasma and the foil trap, or a detection sensor connected to the detachable member and detecting a state of the plasma. [13] The contaminant trap unit according to claim 1, wherein the detachable member comprises a guide mechanism that guides an attachment position with respect to the chamber main body. [14] A light source device comprising: a plasma generation section that converts a plasma raw material into plasma, a chamber main body having an outlet for radiation from the plasma generated by the plasma generation section and an opening different from the outlet, and a contaminant trap unit attached to the opening of the chamber main body, wherein the contaminant trap unit comprises a detachable member covering the opening and configured to be attached to / detached from the chamber main body, and at least one foil trap comprising a plurality of foils for trapping contaminants from the plasma and connected to the detachable member such that the plurality of foils are arranged on a path of radiation from the plasma to the outlet, the detachable member being attached to the chamber main body.

Images