Extreme-ultraviolet light generator and method for manufacturing electronic device

Abstract

To provide an extreme-ultraviolet light generator capable of suppressing unstable output of extreme-ultraviolet light.SOLUTION: An extreme-ultraviolet light generator includes: a chamber for generating extreme-ultraviolet light by irradiating a target substance supplied to an internal space with a laser beam; a target supply part for supplying a droplet of the target substance toward a plasma generation region; a light condensing mirror which is arranged in the internal space and condenses the extreme-ultraviolet light; a debris shield which has a first opening and a second opening through which the extreme-ultraviolet light passes toward the light condensing mirror from the plasma generation region, and surrounds the plasma generation region; a gas supply port for supplying gas to the internal space; and an exhaust port for exhausting the gas in the space surrounded by the debris shield. At least a part of the second opening is provided at a position symmetrical to at least a part of the first opening with a plane including the orbit of the laser beam and the orbit of the droplet being a reference, and the gas in the internal space flows into the space through the first opening and the second opening.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present disclosure relates to an extreme ultraviolet light generating apparatus and a method for manufacturing an electronic device.

Background Art

[0002] In recent years, with the miniaturization of semiconductor processes, the miniaturization of transfer patterns in optical lithography of semiconductor processes has been rapidly progressing. In the next generation, microfabrication of 10 nm or less will be required. For this reason, the development of a semiconductor exposure apparatus that combines an apparatus for generating extreme ultraviolet (EUV) light having a wavelength of about 13 nm and a reduction projection reflective optical system is expected.

[0003] As an EUV light generating apparatus, the development of a Laser Produced Plasma (LPP) type apparatus that uses plasma generated by irradiating a target material with laser light is in progress.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

[0005] An extreme ultraviolet light generating device according to one aspect of the present disclosure includes a chamber that generates extreme ultraviolet light by irradiating a target material supplied to a plasma generation region in an internal space with laser light, a target supply unit that supplies droplets of the target material toward the plasma generation region, a condenser mirror that is disposed in the internal space and condenses the extreme ultraviolet light, a first opening and a second opening through which the extreme ultraviolet light passes from the plasma generation region toward the condenser mirror, a debris shield that surrounds the plasma generation region, a gas supply port that is provided in the chamber and supplies gas to the internal space, and an exhaust port that exhausts the gas in the space surrounded by the debris shield. At least a part of the second opening is provided at a position symmetric to at least a part of the first opening with respect to a plane including the orbit of the laser light and the orbit of the droplets. The gas in the internal space may flow into the space through the first opening and the second opening.

[0006] Further, a method for manufacturing an electronic device according to one aspect of the present disclosure includes a chamber that generates extreme ultraviolet light by irradiating a target material supplied to a plasma generation region in an internal space with laser light, a target supply unit that supplies droplets of the target material toward the plasma generation region, a condenser mirror that is disposed in the internal space and condenses the extreme ultraviolet light, a first opening and a second opening through which the extreme ultraviolet light passes from the plasma generation region toward the condenser mirror, a debris shield that surrounds the plasma generation region, a gas supply port that is provided in the chamber and supplies gas to the internal space, and an exhaust port that exhausts the gas in the space surrounded by the debris shield. At least a part of the second opening is provided at a position symmetric to at least a part of the first opening with respect to a plane including the orbit of the laser light and the orbit of the droplets. The method may include outputting extreme ultraviolet light from the extreme ultraviolet light generating device, in which the gas in the internal space flows into the space through the first opening and the second opening, to an exposure device, and exposing a photosensitive substrate with the extreme ultraviolet light in the exposure device in order to manufacture an electronic device.

[0007] Moreover, a method for manufacturing an electronic device according to another aspect of the present disclosure includes a chamber that generates extreme ultraviolet light by irradiating a target substance supplied to a plasma generation region in an internal space with a laser beam, a target supply unit that supplies droplets of the target substance toward the plasma generation region, a condenser mirror that is disposed in the internal space and condenses the extreme ultraviolet light, a first aperture and a second aperture through which the extreme ultraviolet light passes from the plasma generation region toward the condenser mirror, a debris shield that surrounds the plasma generation region, a gas supply port that is provided in the chamber and supplies gas to the internal space, and an exhaust port that exhausts the gas in the space surrounded by the debris shield. At least a part of the second aperture is provided at a position symmetric to at least a part of the first aperture with respect to a plane including the orbit of the laser beam and the orbit of the droplets. The gas in the internal space irradiates a mask with the extreme ultraviolet light generated by an extreme ultraviolet light generation device that flows into the space through the first aperture and the second aperture to inspect for defects in the mask, selects the mask using the results of the inspection, and may include exposing and transferring the pattern formed on the selected mask onto a photosensitive substrate.

Brief Description of the Drawings

[0008] Some embodiments of the present disclosure will be described below by way of example only with reference to the accompanying drawings.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

[0009] 1. Overview 2. Description of the manufacturing apparatus for electronic devices 3. Description of the extreme ultraviolet light generating apparatus of the comparative example 3.1 Configuration 3.2 Operation 3.3 Problems 4. Description of the extreme ultraviolet light generating apparatus of Embodiment 1 4.1 Configuration 4.2 Operation 4.3 Function and effect 5. Description of the extreme ultraviolet light generating apparatus of Embodiment 2 5.1 Configuration 5.2 Operation 5.3 Function and effect

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The embodiments described below show some examples of the present disclosure and do not limit the content of the present disclosure. Also, not all of the configurations and operations described in each embodiment are essential as the configurations and operations of the present disclosure. Note that the same reference numerals are assigned to the same components, and redundant descriptions are omitted.

[0011] 1. Overview Embodiments of the present disclosure relate to an extreme ultraviolet light generation device that generates light having a wavelength called extreme ultraviolet (EUV), and a manufacturing device for electronic devices. Hereinafter, extreme ultraviolet light may be referred to as EUV light in some cases.

[0012] 2. Description of Manufacturing Device for Electronic Devices FIG. 1 is a schematic diagram showing an overall schematic configuration example of a manufacturing device for electronic devices. The manufacturing device for electronic devices shown in FIG. 1 includes an EUV light generation device 100 and an exposure device 200. The exposure device 200 includes a mask irradiation unit 210 including a plurality of mirrors 211 and 212 that are reflective optical systems, and a workpiece irradiation unit 220 including a plurality of mirrors 221 and 222 that are reflective optical systems different from the reflective optical system of the mask irradiation unit 210. The mask irradiation unit 210 illuminates the mask pattern on the mask table MT through the mirrors 211 and 212 with the EUV light 101 incident from the EUV light generation device 100. The workpiece irradiation unit 220 forms an image of the EUV light 101 reflected by the mask table MT on a workpiece (not shown) disposed on the workpiece table WT through the mirrors 221 and 222. The workpiece is a photosensitive substrate such as a semiconductor wafer coated with photoresist. The exposure device 200 exposes the workpiece to the EUV light 101 reflecting the mask pattern by synchronously translating the mask table MT and the workpiece table WT in parallel. A semiconductor device can be manufactured by transferring a device pattern onto a semiconductor wafer through the exposure process as described above.

[0013] FIG. 2 is a schematic diagram showing an overall schematic configuration example of an electronic device manufacturing apparatus different from the electronic device manufacturing apparatus shown in FIG. 1. The electronic device manufacturing apparatus shown in FIG. 2 includes an EUV light generation apparatus 100 and an inspection apparatus 300. The inspection apparatus 300 includes an illumination optical system 310 including a plurality of mirrors 311, 313, 315 that are reflective optical systems, and a detection optical system 320 including a plurality of mirrors 321, 323 that are reflective optical systems different from the reflective optical system of the illumination optical system 310 and a detector 325. The illumination optical system 310 reflects the EUV light 101 incident from the EUV light generation apparatus 100 with the mirrors 311, 313, 315 and irradiates the mask 333 disposed on the mask stage 331. The mask 333 includes mask blanks before a pattern is formed. The detection optical system 320 reflects the EUV light 101 reflecting the pattern from the mask 333 with the mirrors 321, 323 and forms an image on the light receiving surface of the detector 325. The detector 325 that has received the EUV light 101 acquires an image of the mask 333. The detector 325 is, for example, a TDI (Time Delay Integration) camera. Based on the image of the mask 333 acquired through the above steps, defects of the mask 333 are inspected, and using the inspection results, a mask suitable for manufacturing an electronic device is selected. Then, an electronic device can be manufactured by exposing and transferring the pattern formed on the selected mask onto a photosensitive substrate using the exposure apparatus 200.

[0014] 3. Description of Extreme Ultraviolet Light Generation Apparatus of Comparative Example 3.1 Configuration The EUV light generation apparatus 100 of the comparative example will be described. Note that the comparative example of the present disclosure is a form recognized by the applicant as being known only to the applicant and is not a known example recognized by the applicant. Further, hereinafter, as shown in FIG. 1, the description will be made using the EUV light generation apparatus 100 that emits the EUV light 101 toward the exposure apparatus 200 as the next process apparatus. Note that the EUV light generation apparatus 100 that emits the EUV light 101 toward the inspection apparatus 300 as the next process apparatus as shown in FIG. 2 can also obtain the same operations and effects.

[0015] FIG. 3 is a schematic diagram showing an overall schematic configuration example of the EUV light generation apparatus 100 of this example. As shown in FIG. 3, the EUV light generation apparatus 100 mainly includes a chamber 10, a laser device LD, a laser beam delivery optical system 30, and a processor 120.

[0016] The chamber 10 is a sealable container. The chamber 10 includes a sub-chamber 11, and a target supply unit 40 is attached to the sub-chamber 11 so as to penetrate the wall of the sub-chamber 11. The target supply unit 40 includes a tank 41, a nozzle 42, and a pressure regulator 43, and supplies droplets DL into the internal space of the chamber 10. The droplets DL may be called a droplet target or a target.

[0017] The tank 41 stores a target material that becomes the droplets DL inside. The target material contains tin. The inside of the tank 41 communicates with a pressure regulator 43 that adjusts the pressure inside the tank 41. A heater 44 and a temperature sensor 45 are attached to the tank 41. The heater 44 heats the tank 41 by an electric current supplied from a heater power supply 46. By this heating, the target material inside the tank 41 melts. The temperature sensor 45 measures the temperature of the target material inside the tank 41 via the tank 41. The pressure regulator 43, the temperature sensor 45, and the heater power supply 46 are electrically connected to the processor 120.

[0018] The nozzle 42 is attached to the tank 41 and discharges the target material. A piezo element 47 is attached to the nozzle 42. The piezo element 47 is electrically connected to a piezo power supply 48 and is driven by a voltage applied from the piezo power supply 48. The piezo power supply 48 is electrically connected to the processor 120. By the operation of the piezo element 47, the target material discharged from the nozzle 42 becomes droplets DL.

[0019] Chamber 10 includes a target recovery section 14. The target recovery section 14 is a box body attached to the chamber 10 and communicates with the internal space of the chamber 10 through an opening 14a provided in the chamber 10. The opening 14a is provided directly below the nozzle 42, and the target recovery section 14 is a drain tank that recovers unnecessary droplets DL that pass through the opening 14a and reach the target recovery section 14.

[0020] The chamber 10 is provided with a window 12 for transmitting light from the outside, and pulsed laser light 90 emitted from the laser device LD passes through the window 12.

[0021] Also, a laser focusing optical system 13 is arranged in the internal space of the chamber 10. The laser focusing optical system 13 includes a laser light focusing mirror 13A and a high reflection mirror 13B. The laser light focusing mirror 13A reflects and focuses the laser light 90 passing through the window 12. The high reflection mirror 13B reflects the laser light 90 focused by the laser light focusing mirror 13A. The positions of the laser light focusing mirror 13A and the high reflection mirror 13B are adjusted by the laser light manipulator 13C so that the focusing position of the laser light 90 in the internal space of the chamber 10 becomes the position specified by the processor 120. The focusing position is adjusted to be located directly below the nozzle 42. When the laser light 90 irradiates the target substance at the focusing position, plasma is generated from the target substance, and EUV light 101 is radiated from the plasma. The region where plasma is generated may be referred to as a plasma generation region AR. The plasma generation region AR is a region having a radius of, for example, 40 mm centered on the plasma point and is located in the internal space of the chamber 10.

[0022] In the internal space of the chamber 10, for example, an EUV light condensing mirror 15 including a reflecting surface 15a having an ellipsoidal shape is disposed. The EUV light condensing mirror 15 includes, for example, a multilayer film in which a silicon layer and a molybdenum layer are alternately laminated, and reflects EUV light 101 by the multilayer film. The EUV light condensing mirror 15 is provided at a position that does not overlap with the optical path of the laser light 90 in the internal space of the chamber 10. The reflecting surface 15a reflects EUV light 101 radiated from the plasma in the plasma generation region AR. The reflecting surface 15a includes a first focus and a second focus. The reflecting surface 15a may be arranged, for example, such that the first focus is located in the plasma generation region AR and the second focus is located at the intermediate focus point IF.

[0023] The EUV light generation apparatus 100 includes a connection portion 19 that communicates the internal space of the chamber 10 and the internal space of the exposure apparatus 200. A wall having an aperture formed therein is disposed in the connection portion 19. This wall is preferably arranged such that the aperture is located at the second focus. The connection portion 19 is also an exit port of the EUV light 101 in the chamber 10, and the EUV light 101 is emitted from the connection portion 19 and enters the exposure apparatus 200.

[0024] A first etching gas supply unit 16 is connected to the chamber 10. The first etching gas supply unit 16 includes a first gas supply port 160. The etching gas contains hydrogen gas, and in this example, the etching gas is hydrogen gas that can be regarded as having a hydrogen concentration of 100%. Therefore, in this example, the first etching gas supply unit 16 further includes a hydrogen tank 161 and a gas pipe 162. The first etching gas supply unit 16 supplies the hydrogen gas in the hydrogen tank 161 to the reflective surface 15a of the EUV light condensing mirror 15 from the first gas supply port 160 through the gas pipe 162. The first etching gas supply unit 16 is controlled by the processor 120. The gas pipe 162 may be provided with a gas flow rate adjusting unit (not shown) which is a valve. When the gas flow rate adjusting unit is provided, for example, the processor 120 controls the gas flow rate adjusting unit to adjust the flow rate of the supplied etching gas. Note that the etching gas may be, for example, a balance gas with a hydrogen gas concentration of about 3%. In this case, the balance gas contains, for example, nitrogen (N2) gas or argon (Ar) gas.

[0025] Further, the EUV light generating apparatus 100 includes a pressure sensor 26 and a detection unit 27 as a target sensor. The pressure sensor 26 and the detection unit 27 are attached to the chamber 10 and electrically connected to the processor 120. The pressure sensor 26 measures the pressure in the internal space of the chamber 10 and outputs a signal indicating this pressure to the processor 120.

[0026] The detection unit 27 includes, for example, an imaging function, and detects the presence, trajectory, position, flow velocity, etc. of the droplets DL ejected from the nozzle holes of the nozzle 42 according to an instruction from the processor 120. The detection unit 27 may be arranged inside the chamber 10, or may be arranged outside the chamber 10 and detect the droplets DL through a window (not shown) provided on the wall of the chamber 10. The detection unit 27 includes a light receiving optical system (not shown) and an imaging unit (not shown) such as a CCD (Charge-Coupled Device) or a photodiode. The light receiving optical system forms an image of the trajectory of the droplets DL and the image around it on the light receiving surface of the imaging unit in order to improve the detection accuracy of the droplets DL. When the droplets DL pass through the light condensing region of the light from a light source (not shown) arranged to improve the contrast within the field of view of the detection unit 27, the imaging unit detects the change in the light passing through the trajectory of the droplets DL and the surroundings. The imaging unit converts the detected change in light into an electrical signal. The electrical signal may include image data of the droplets DL. The imaging unit outputs this electrical signal to the processor 120.

[0027] The laser device LD includes a master oscillator which is a light source that operates in a burst mode. The master oscillator emits pulsed laser light 90 when it is in burst on. The master oscillator is, for example, a solid-state laser device that excites a YAG crystal doped with niobium (Nb) or ytterbium (Yb), or a laser device that emits laser light 90 by exciting a gas in which helium, nitrogen, etc. are mixed in carbon dioxide gas by discharge. Alternatively, the master oscillator may be a quantum cascade laser device. Also, the master oscillator may emit pulsed laser light 90 by a Q-switching method. Further, the master oscillator may include an optical switch, a polarizer, etc. The laser device LD may include an amplifier that amplifies the laser light 90 emitted by the master oscillator. Note that the burst operation is an operation in which burst on for emitting continuous pulsed laser light 90 at a predetermined repetition frequency and burst off for suppressing the emission of the laser light 90 are repeatedly performed.

[0028] The traveling direction of the laser beam 90 emitted from the laser device LD is adjusted by the laser beam delivery optical system 30. The laser beam delivery optical system 30 includes a plurality of mirrors 31, 32 that adjust the traveling direction of the laser beam 90. The position of at least one of the mirrors 31, 32 is adjusted by an actuator (not shown). By adjusting the position of at least one of the mirrors 31, 32, the laser beam 90 can appropriately propagate from the window 12 into the internal space of the chamber 10.

[0029] A beam splitter 33 is provided between the mirror 32 and the window 12. The beam splitter 33 transmits most of the laser beam 90 reflected by the mirror 32 and reflects a part of the laser beam 90. A laser beam measuring device 34 is provided at the destination where the laser beam 90 reflected by the beam splitter 33 travels. The laser beam measuring device 34 includes a light receiving element, measures the power of the received laser beam 90, and outputs a signal related to the power of the laser beam 90. The laser beam measuring device 34 is electrically connected to the processor 120, and the signal related to the power of the laser beam 90 is input to the processor 120.

[0030] The processor 120 of the present disclosure is a processing device including a storage device storing a control program and a CPU (Central Processing Unit) that executes the control program. The processor 120 is specially configured or programmed to execute various processes included in the present disclosure and controls the entire EUV light generation device 100. Signals related to the pressure of the internal space of the chamber 10 measured by the pressure sensor 26, signals related to the image data of the droplet DL imaged by the detection unit 27, a burst signal for instructing a burst operation from the exposure device 200, etc. are input to the processor 120. The processor 120 processes the above various signals and may control, for example, the timing at which the droplet DL is ejected, the ejection direction of the droplet DL, etc. Further, the processor 120 may control the emission timing of the laser device LD, the traveling direction and the focusing position of the laser beam 90, etc. The various controls described above are merely examples, and other controls may be added as described later as necessary.

[0031] FIG. 4 is a schematic diagram showing a cross-section of the EUV light generating apparatus 100 perpendicular to the trajectory of the droplet DL in the comparative example, and FIG. 5 is a schematic diagram showing a cross-section of the EUV light generating apparatus 100 along the trajectory of the droplet DL in the comparative example. In FIGS. 4 and 5, for simplicity of illustration, the laser light condensing mirror 13A and the high reflection mirror 13B are omitted, and the traveling path of the laser light 90 from the window 12 to the plasma generation region AR is simply illustrated.

[0032] The EUV light generating apparatus 100 includes a cylindrical debris shield 18 that extends from the internal space of the chamber 10 to the external space of the chamber 10. The inner diameter of the debris shield 18 is preferably 90 mm or more and 160 mm or less. In FIGS. 4 and 5, the space outside the debris shield 18 in the internal space of the chamber 10 is shown as the first space 10a, and the space inside the debris shield 18 is shown as the second space 10b. Note that in FIG. 3, the illustration of the debris shield 18 is omitted.

[0033] The debris shield 18 surrounds the plasma generation region AR. That is, the plasma generation region AR is located in the second space 10b. The debris shield 18 is a partition wall that suppresses debris such as target substances scattered from the plasma generation region AR from scattering into the first space 10a. A first opening 181 is provided at one end of the debris shield 18 located in the internal space of the chamber 10, and a gas exhaust port 189 is provided at the other end of the debris shield 18 located outside the chamber 10. The gas exhaust port 189 is connected to an exhaust device 180 including an exhaust pump. Therefore, at least a part of the gas in the first space 10a flows into the second space 10b from the first opening 181 and is discharged from the gas exhaust port 189. The debris shield 18 has a cylindrical shape whose longitudinal direction extends from the first opening 181 toward the gas exhaust port 189, that is, a cylindrical shape whose longitudinal direction extends in the gas exhaust direction. Note that the shape of the cross-section perpendicular to the longitudinal direction of the debris shield 18 may be circular or non-circular. Also, the thickness of the debris shield 18 does not have to be constant.

[0034] The first opening 181 is provided between the plasma generation region AR and the EUV light condensing mirror 15. Therefore, the EUV light 101 generated in the plasma generation region AR passes through the first opening 181 toward the EUV light condensing mirror 15. The EUV light condensing mirror 15 reflects the EUV light 101 incident from the first opening 181 toward an intermediate condensing point IF located in a direction different from the incident direction of the EUV light 101.

[0035] Also, a laser light incident opening 183, a droplet supply opening 184, and a droplet discharge opening 185 are provided in the side wall of the debris shield 18. The laser light incident opening 183 is provided on the optical path of the laser light 90 to the plasma generation region AR in the internal space of the chamber 10. The laser light 90 enters the plasma generation region AR from the first space 10a through the laser light incident opening 183. A laser damper 91 is provided on the side opposite to the laser light incident opening 183 with respect to the plasma generation region AR in the debris shield 18. The laser damper 91 is irradiated with the laser light 90 that has not been irradiated to the droplet DL, and converts the optical energy of the laser light 90 into heat. The droplet supply opening 184 and the droplet discharge opening 185 are provided on the trajectory of the droplet DL and face each other. The droplet DL is supplied from the target supply unit 40 to the plasma generation region AR through the droplet supply opening 184. The droplet discharge opening 185 faces an opening 14a connected to the target recovery unit 14, and the droplet DL that has passed through the plasma generation region AR enters the target recovery unit 14 through the droplet discharge opening 185. In this example, the areas of the droplet supply opening 184 and the droplet discharge opening 185 are substantially the same as each other and are larger than the area of the laser light incident opening 183. Also, the area of the first opening 181 is larger than the areas of the other openings excluding the gas exhaust port 189 provided in the debris shield 18.

[0036] In this example, the debris shield 18 is provided with a plurality of sensors 28a and 28b for monitoring the state inside the second space 10b. The sensors 28a and 28b may include, for example, target sensors that monitor the state of the plasma generation region AR or its vicinity and detect at least one of the presence, trajectory, position, and velocity of the droplet DL, and may also include sensors that detect the light emission point of the EUV light 101. The sensors 28a and 28b include, for example, an image sensor or an optical sensor, and an optical system that forms an image of the plasma generation region AR or its vicinity on the image sensor or the optical sensor. Although not particularly shown, a light source that illuminates the plasma generation region AR with visible light may be arranged. In FIG. 3, the illustration of the sensors 28a and 28b is omitted.

[0037] The first etching gas supply unit 16 supplies the etching gas in the hydrogen tank 161 to the first space 10a in the internal space of the chamber 10 from the first gas supply port 160 through the gas pipe 162. In this example, the etching gas is supplied toward the reflection surface 15a of the EUV light condensing mirror 15. The flow rate of the etching gas supplied from the first etching gas supply unit 16 to the first space 10a is, for example, 10 l / min or more and 100 l / min or less. Note that the flow rate of the etching gas may be indicated by nlm, which is the volume of the etching gas flowing per minute converted to 0°C and 1 atm. Since the area of the first opening 181 is larger than the area of the other openings excluding the gas exhaust port 189 provided in the debris shield 18 as described above, the etching gas supplied to the first space 10a mainly flows into the second space 10b through the first opening 181 as indicated by the arrow in FIGS. 4 and 5. However, the etching gas may also flow into the second space 10b from the laser light incident opening 183, the droplet supply opening 184, and the droplet discharge opening 185.

[0038] Since the target substance contains tin as described above, when the target substance is irradiated with the laser beam 90 in the plasma generation region AR and turned into plasma, tin fine particles and tin charged particles are generated. Further, hydrogen contained in the etching gas supplied from the first etching gas supply unit 16 into the internal space of the chamber 10 becomes hydrogen radicals by the energy of the EUV light 101. Tin that constitutes the fine particles and the charged particles reacts with the hydrogen radicals. When tin reacts with the hydrogen radicals, gaseous stannane (SnH4) is generated at room temperature.

[0039] When the target substance is turned into plasma in the plasma generation region AR, residual gas as exhaust gas is generated in the second space 10b. The residual gas includes tin fine particles and charged particles generated by the plasma generation of the target substance, stannane formed by their reaction with the etching gas, and unreacted etching gas. Note that a part of the charged particles is neutralized in the second space 10b, and the neutralized charged particles are also included in the residual gas. The gas exhaust port 189 exhausts the etching gas that has flowed from the first space 10a to the second space 10b, together with the residual gas, to the outside of the chamber 10. Specifically, the gas exhaust port 189 exhausts the etching gas and the residual gas to the exhaust device 180 by the suction of the exhaust device 180.

[0040] 3.2 Operation Next, the operation of the EUV light generation device 100 of the comparative example will be described.

[0041] In the EUV light generation device 100, for example, when newly introduced or during maintenance, the atmosphere in the internal space of the chamber 10 is exhausted. At this time, for exhausting the atmospheric components, the purging and exhausting of the internal space of the chamber 10 may be repeated. As the purge gas, for example, an inert gas such as nitrogen or argon is preferably used. Then, when the pressure in the internal space of the chamber 10 becomes equal to or lower than a predetermined pressure, the processor 120 starts introducing an etching gas into the first space 10a of the chamber 10 through the first gas supply port 160 of the first etching gas supply unit 16. At this time, the processor 120 may control the supply gas flow rate adjustment unit and the exhaust device 180 so that the pressure in the internal space of the chamber 10 is maintained at a predetermined pressure. Then, the processor 120 waits until a predetermined time has elapsed since the start of introducing the etching gas.

[0042] Further, the processor 120 exhausts the gas in the internal space of the chamber 10 from the gas exhaust port 189 by the exhaust device 180, and maintains the pressure in the internal space of the chamber 10 substantially constant based on a signal indicating the pressure in the internal space of the chamber 10 measured by the pressure sensor 26.

[0043] Further, the processor 120 supplies an electric current from the heater power supply 46 to the heater 44 to heat and maintain the target substance in the tank 41 at a predetermined temperature equal to or higher than the melting point, and raises the temperature of the heater 44. At this time, the processor 120 adjusts the value of the electric current supplied from the heater power supply 46 to the heater 44 based on the output from the temperature sensor 45, and controls the temperature of the target substance at a predetermined temperature. Note that the predetermined temperature is a temperature equal to or higher than the melting point of tin, 231.93°C, when the target substance is tin, and is, for example, 240°C or higher and 290°C or lower. Thus, the preparation for discharging the droplet DL is completed.

[0044] When the preparation is completed, the processor 120 supplies an inert gas from a gas supply source (not shown) into the tank 41 by means of the pressure regulator 43 so that the molten target substance is discharged from the nozzle holes of the nozzle 42 at a predetermined flow rate, and adjusts the pressure in the tank 41. Under this pressure, the target substance is discharged from the nozzle holes of the nozzle 42 into the first space 10a of the chamber 10. The target substance discharged from the nozzle holes may take the form of a jet. At this time, the processor 120 applies a voltage of a predetermined waveform from the piezo power supply 48 to the piezo element 47 in order to generate the droplet DL. The piezo power supply 48 applies a voltage such that the voltage waveform is, for example, sinusoidal, rectangular, or sawtooth. The vibration of the piezo element 47 propagates to the target substance discharged from the nozzle holes of the nozzle 42 via the nozzle 42. The target substance is segmented at a predetermined period by this vibration and becomes the droplet DL of the droplet. The diameter of the droplet DL is generally 10 μm or more and 30 μm or less.

[0045] When the droplet DL of the target substance is discharged, it travels through the droplet supply opening 184 and proceeds to the plasma generation region AR. The detection unit 27 detects the passing timing of the droplet DL passing through a predetermined position in the second space 10b of the chamber 10. The processor 120 outputs a trigger signal for controlling the timing at which the laser beam 90 is emitted from the laser device LD based on the signal from the detection unit 27 so that the droplet DL is irradiated with the laser beam 90. The trigger signal output from the processor 120 is input to the laser device LD. When the trigger signal is input, the laser device LD emits a pulsed laser beam 90.

[0046] The emitted laser beam 90 enters the laser focusing optical system 13 via the laser beam delivery optical system 30 and the window 12. At this time, the laser beam 90 reflected by the beam splitter 33 is received by the laser beam measuring instrument 34, and its power is measured. The laser beam measuring instrument 34 outputs a signal related to the measured power of the laser beam 90 to the processor 120. Based on the signal input from the laser beam measuring instrument 34, the processor 120 controls the laser device LD to emit the laser beam 90 with a desired power from the laser device LD. The laser beam 90 travels from the laser focusing optical system 13 through the laser beam incident aperture 183 and towards the plasma generation region AR. Then, the laser beam 90 irradiates the droplet DL in the plasma generation region AR. At this time, the processor 120 controls the laser beam manipulator 13C of the laser focusing optical system 13 so that the laser beam 90 is focused on the plasma generation region AR. Also, the processor 120 controls the timing of emitting the laser beam 90 from the laser device LD based on the signal from the detection unit 27 so that the laser beam 90 irradiates the droplet DL. As a result, the laser beam 90 focused by the laser focusing mirror 13A irradiates the droplet DL in the plasma generation region AR. Plasma is generated by this irradiation, and light including EUV light 101 is emitted from the plasma.

[0047] Among the light including EUV light 101 generated in the plasma generation region AR, the EUV light 101 passes through the first aperture 181 and travels towards the EUV light focusing mirror 15. After being focused by the EUV light focusing mirror 15 at the intermediate focus point IF, it enters the exposure apparatus 200 from the connection part 19.

[0048] Hydrogen contained in the etching gas supplied from the first gas supply port 160 becomes hydrogen radicals due to the energy of the EUV light 101. Therefore, when tin is deposited on the reflective surface 15a of the EUV light condenser mirror 15 or on the inner peripheral surface of the debris shield 18, the tin reacts with the hydrogen radicals to become stannane and is removed from the reflective surface 15a and the inner peripheral surface of the debris shield 18. The etching gas and stannane in the first space 10a mainly flow into the second space 10b from the first opening 181. The exhaust device 180 sucks the etching gas together with the residual gas in the second space 10b through the gas exhaust port 189. Thereby, the gas in the second space 10b is exhausted to the outside of the chamber 10. The gas sucked by the exhaust device 180 is subjected to a predetermined exhaust treatment such as detoxification.

[0049] 3.3 Problems FIG. 6 is a diagram showing the progress of the droplet DL and the flow of gas in the second space 10b. In FIG. 6, the chamber 10 is omitted, and the gas flow is indicated by arrows. As shown in FIG. 6, the trajectory of the droplet DL slightly changes due to the gas flow that flows in from the first opening 181 and heads toward the gas exhaust port 189. However, the processor 120 controls the laser light manipulator 13C so that the trajectory of the droplet DL is detected by the detection unit 27 and the sensors 28a, 28b, etc., and the laser light 90 is irradiated on the detected trajectory of the droplet DL, and the positions of the laser light condenser mirror 13A and the highly reflective mirror 13B are adjusted. For this reason, the laser light 90 is irradiated on the droplet DL.

[0050] FIG. 7 is a diagram showing the progress of the droplet DL and the flow of gas in the second space 10b immediately after the droplet DL is irradiated with the laser beam 90. When the droplet DL is irradiated with the laser beam 90, the heat and shock wave generated from the droplet DL cause the plasma generation region AR and the gas density in the periphery indicated by the broken line of the plasma generation region AR to decrease. As a result, the gas flow changes temporarily. Due to this change in the gas flow, the trajectory of the droplet DL may deviate temporarily from the irradiation position of the laser beam 90, and the laser beam 90 may not be irradiated to the droplet DL. For this reason, the output of the EUV light 101 may become unstable.

[0051] Therefore, in the following embodiments, an EUV light generation apparatus 100 capable of suppressing the output of the EUV light 101 from becoming unstable is exemplified.

[0052] 4. Description of the extreme ultraviolet light generation apparatus according to Embodiment 1 The configuration of the EUV light generation apparatus 100 according to Embodiment 1 will be described. Components having the same configuration as those described above are denoted by the same reference numerals, and redundant descriptions are omitted unless otherwise specified.

[0053] 4.1 Configuration FIG. 8 is a schematic diagram showing a cross section of the chamber 10 of the EUV light generation apparatus 100 according to the present embodiment perpendicular to the longitudinal direction of the debris shield 18, and FIG. 9 is a schematic diagram showing a cross section of a part of the components in the chamber 10 along the longitudinal direction of the debris shield 18.

[0054] As shown in FIGS. 8 and 9, in the present embodiment, the EUV light condensing mirror 15 is disposed laterally in the radial direction of the cylindrical debris shield 18. Therefore, the first opening 181 is provided in the side wall of the debris shield 18. Further, in the present embodiment, the first gas supply port 160 is provided in the chamber 10 so as to supply an etching gas from the side of the EUV light condensing mirror 15 with respect to the debris shield 18 into the internal space of the chamber 10. Also in the present embodiment, the first gas supply port 160 supplies the etching gas toward the reflecting surface 15a of the EUV light condensing mirror 15. At least a part of the etching gas supplied from the first gas supply port 160 is guided to the first opening 181 by the EUV light condensing mirror 15.

[0055] Also, in the present embodiment, the droplet supply opening 184 is provided at an end portion in the longitudinal direction of the debris shield 18. Therefore, the target supply unit 40 supplies the droplet DL into the second space 10b from the end side of the debris shield 18 along the longitudinal direction of the debris shield 18 through the droplet supply opening 184. For this reason, in the present embodiment, the target recovery unit 14 is provided in the second space 10b.

[0056] Also in the present embodiment, the laser beam 90 is irradiated onto the plasma generation region AR through the laser beam incident opening 183 in the same manner as in the comparative example. In the present embodiment, a laser beam emission opening 186 is provided on the side of the debris shield 18 opposite to the laser beam incident opening 183 with respect to the plasma generation region AR. Further, a laser damper 91 is provided at a position where the laser beam passes from the laser beam incident opening 183 to the laser beam emission opening 186. For this reason, the laser beam 90 that has not been irradiated onto the droplet DL is irradiated onto the laser damper 91 through the laser beam emission opening 186 and is subjected to photothermal conversion.

[0057] Since the laser beam 90 is irradiated non-parallel to the trajectory of the droplet DL, a plane S including the trajectory of the laser beam 90 and the trajectory of the droplet DL can be defined. In FIG. 9, this plane S is shown slightly shifted from the trajectory of the droplet DL. The plane S is perpendicular to the paper surface of FIGS. 8 and 9. The first gas supply port 160 is located on the same side as the side where the first opening 181 is located with respect to the plane S.

[0058] In the present embodiment, a second gas supply port 170 is provided on the side opposite to the first gas supply port 160 side with respect to the debris shield 18 of the chamber 10. The first gas supply port 160 and the second gas supply port 170 constitute a gas supply port for supplying an etching gas into the internal space of the chamber 10. Although not particularly shown, a gas pipe similar to the gas pipe 162 is connected to the second gas supply port 170, and a hydrogen tank similar to the hydrogen tank 161 is connected to the gas pipe. Therefore, the second gas supply port 170 supplies an etching gas to the first space 10a. At least a part of the second gas supply port 170 is preferably provided at a position symmetric to at least a part of the first gas supply port 160 with respect to the plane S. Further, it is preferable that the first gas supply port 160 and the second gas supply port 170 supply the same amount of etching gas. Further, when the first gas supply port 160 and the second gas supply port 170 have the same area, it is preferable from the viewpoint of making the flow rates of the etching gas supplied from the respective supply ports closer to each other when supplying the same amount of etching gas from the respective supply ports. Further, it is preferable that the first gas supply port 160 and the second gas supply port 170 have the same shape from the viewpoint of making the flow directions of the gas flowing into the first space 10a from the first gas supply port 160 and the second gas supply port 170 closer to each other. Further, in the direction perpendicular to the plane S, it is preferable that 95% or more of the first gas supply port 160 and the second gas supply port 170 overlap each other, from the viewpoint of enhancing the symmetry of the first gas supply port 160 and the second gas supply port 170 with respect to the plane S and enhancing the symmetry of the gas flow supplied from the first gas supply port 160 and the gas flow supplied from the second gas supply port 170.

[0059] In addition, in the present embodiment, a second opening 182 is provided in the debris shield 18. At least a part of the second opening 182 is provided at a position symmetric to at least a part of the first opening 181 with respect to the plane S. Therefore, with respect to the plane S, the second opening 182 and the second gas supply port 170 are provided on the same side. For this reason, at least a part of the etching gas supplied from the second gas supply port 170 flows into the second space 10b from the second opening 182.

[0060] It is preferable that the first opening 181 and the second opening 182 have the same area from the viewpoint of making the amounts of gas flowing into the second space 10b from the first opening 181 and the second opening 182 closer. Also, it is preferable that the first opening 181 and the second opening 182 have the same shape from the viewpoint of making the flow directions of the gas flowing into the second space 10b from the first opening 181 and the second opening 182 closer. Further, it is preferable that the first opening 181 and the second opening 182 have a larger area than other openings provided in the debris shield 18 from the viewpoint that the flow of the gas flowing in from the first opening 181 and the second opening 182 can be dominant over the influence on the flow of the gas toward the gas exhaust port 189 in the second space 10b. Also, in the direction perpendicular to the plane S, it is preferable that at least 95% of the first opening 181 and the second opening 182 overlap each other, from the viewpoint of enhancing the symmetry of the first opening 181 and the second opening 182 with respect to the plane S and enhancing the symmetry of the gas flowing into the second space 10b from the first opening 181 and the gas flowing into the second space 10b from the second opening 182.

[0061] In this embodiment, an auxiliary plate 25 is provided on the side of the debris shield 18 on the second opening 182 side. The auxiliary plate 25 guides the etching gas supplied from the second gas supply port 170 to the second opening 182. It is preferable that at least a part of the auxiliary plate 25 is provided at a position symmetric with the EUV light condensing mirror 15 with respect to the plane S from the viewpoint of making the amount of gas flowing into the second space 10b from the first opening 181 and the second opening 182 closer. The auxiliary plate 25 of this embodiment has the same shape as the EUV light condensing mirror 15 and is arranged to be symmetric with respect to the plane S. Therefore, the auxiliary plate 25 has a concave shape that is concave in a direction symmetric to the direction in which the EUV light condensing mirror 15 is concave with respect to the plane S. Note that when the auxiliary plate 25 does not have the same shape as the EUV light condensing mirror 15, it preferably has a concave shape that is concave in a direction symmetric to the direction in which the EUV light condensing mirror 15 is concave with respect to the plane S, but it may also be a flat plate.

[0062] In this embodiment, sensors 28a and 28b are attached to the auxiliary plate 25. The sensors 28a and 28b observe the state inside the second space 10b through the second opening 182.

[0063] 4.2 Operation In the EUV light generation apparatus 100 of the present embodiment, etching gas is supplied from the first gas supply port 160 and the second gas supply port 170 during a period similar to the period in which the etching gas is supplied from the first gas supply port 160 in the comparative example. In FIGS. 8 and 9, the gas flow is indicated by arrows. The etching gas supplied from the first gas supply port 160 flows along the surface of the reflection surface 15a of the EUV light condensing mirror 15 and mainly flows into the second space 10b from the first opening 181. At this time, the etching gas forms a flow that prevents tin fine particles and the like generated in the plasma generation region from passing through the first opening 181 and advancing to the reflection surface 15a. Further, tin fine particles and the like that have been decelerated and stopped by this flow flow into the second space 10b from the first opening 181 along the reverse flow. Therefore, it is possible to suppress tin fine particles and the like generated in the debris shield 18 from scattering into the first space 10a where the EUV light condensing mirror 15 is disposed. Further, as described above, the etching gas becomes hydrogen radicals due to light divergence associated with EUV light generation and removes tin debris adhering to the reflection surface 15a to generate stannane, so that the residual gas containing stannane also mainly flows into the second space 10b from the first opening 181. On the other hand, the etching gas supplied from the second gas supply port 170 flows along the surface of the auxiliary plate 25 and flows into the second space 10b from the second opening 182 together with the residual gas on the second gas supply port 170 side of the plane S. The gas flowing in from the first opening 181 and the second opening 182 flows toward the gas exhaust port 189.

[0064] In the present embodiment, the amount of gas flowing into the second space 10b from the first opening 181 and the second opening 182 is preferably 20 nlm or more and 60 nlm or less, and the amount of gas flowing into the second space 10b from the laser light incident opening 183, the droplet supply opening 184, and the laser light emission opening 186 is preferably 1 nlm or more and 20 nlm or less.

[0065] When the droplets DL discharged from the target supply unit 40 are supplied into the second space 10b through the droplet supply opening 184, the droplets DL are affected by the gas flow in the second space 10b. However, in the present embodiment, the first opening 181 and the second opening 182 are provided at symmetric positions with respect to the plane S. Therefore, the gas flow flowing in from the first opening 181 and the gas flow flowing in from the second opening 182 are substantially symmetric with respect to the plane S. For this reason, in the second space 10b, compared with the case where the second opening 182 is not provided or the case where the first opening 181 and the second opening 182 are provided at asymmetric positions with respect to the plane S, the droplets DL are less affected by the gas flow.

[0066] Further, when the laser beam 90 irradiates the droplet DL, the gas density in the plasma generation region AR and its surroundings decreases due to the heat and shock wave generated from the droplet DL. However, in the present embodiment, as described above, since the gas flow flowing in from the first opening 181 and the gas flow flowing in from the second opening 182 are substantially symmetric with respect to the plane S, the direction in which the trajectory of the droplet DL changes is the direction along the optical axis of the laser beam 90. For this reason, the laser beam 90 immediately after the laser beam 90 irradiates the droplet DL irradiates the droplet DL.

[0067] 4.3 Action and Effect In the EUV light generation device 100 of the present embodiment, at least a part of the second aperture 182 is provided at a position symmetric to at least a part of the first aperture 181 with respect to a plane S including the orbit of the laser beam 90 and the orbit of the droplet DL. The first gas supply port 160 is provided on the side where the first aperture 181 is located with respect to the plane S, the second gas supply port 170 is provided on the side where the second aperture 182 is located with respect to the plane S, and the gas in the first space 10a flows into the second space 10b through the first aperture 181 and the second aperture 182. With such a configuration, it is possible to suppress the laser beam 90 from irradiating the droplet DL immediately after the laser beam 90 is irradiated. Therefore, according to the EUV light generation device 100 of the present embodiment, it is possible to suppress the output of the EUV light 101 from becoming unstable.

[0068] Also, in the present embodiment, the target supply unit 40 supplies the droplet DL along the longitudinal direction of the debris shield 18. For this reason, the recovery direction of the droplet DL and the exhaust direction of the gas are the same. Accordingly, when providing a tin recovery mechanism (not shown) that recovers tin from stannane and tin fine particles flowing together with the etching gas, there is a possibility that the target recovery unit 14 and the tin recovery mechanism can be integrated.

[0069] 5. Description of the extreme ultraviolet light generation device of Embodiment 2 Next, the configuration of the EUV light generation device 100 of Embodiment 2 will be described. Note that the same components as those described above are denoted by the same reference numerals, and redundant descriptions are omitted unless otherwise specified.

[0070] 5.1 Configuration FIG. 10 is a schematic diagram showing a cross section of the chamber 10 of the EUV light generation device 100 of the present embodiment along the longitudinal direction of the debris shield 18, and FIG. 11 is a schematic diagram showing a cross section of a part of the components in the chamber 10 perpendicular to the longitudinal direction of the debris shield 18. Note that also in FIG. 11, the plane S is shown slightly shifted from the orbit of the droplet DL.

[0071] The EUV light generation device 100 of this embodiment is different from the EUV light generation device 100 of Embodiment 1 in that the longitudinal direction of the debris shield 18 is along the irradiation direction of the laser beam 90. For this reason, in this embodiment, the laser beam incident aperture 183 is provided at the end in the longitudinal direction of the debris shield 18. Further, the laser damper 91 is provided inside the debris shield 18. In this embodiment, the laser beam 90 is irradiated along the central axis in the radial direction of the second space 10b. Since the laser beam 90 is irradiated along the longitudinal direction of the debris shield 18, in this embodiment, the first aperture 181 and the second aperture 182 are mirror-symmetrical with the plane S as the mirror plane.

[0072] Further, the droplet supply aperture 184 and the droplet discharge aperture 185 are provided on the side wall of the debris shield 18 in the same manner as in the comparative example.

[0073] 5.2 Operation In FIGS. 10 and 11, the gas flow is indicated by arrows. Also in this embodiment, the etching gas supplied from the first gas supply port 160 flows along the surface of the reflecting surface 15a of the EUV light condensing mirror 15, and the etching gas that does not react with tin and the residual gas containing stannane on the side of the first gas supply port 160 from the plane S mainly flow into the second space 10b from the first aperture 181. Further, the etching gas supplied from the second gas supply port 170 flows along the surface of the auxiliary plate 25, and the etching gas that does not react with tin and the residual gas containing stannane on the side of the second gas supply port 170 from the plane S mainly flow into the second space 10b from the second aperture 182.

[0074] Also in this embodiment, the first aperture 181 and the second aperture 182 are provided at symmetrical positions with respect to the plane S. For this reason, the gas flow flowing in from the first aperture 181 and the gas flow flowing in from the second aperture 182 are substantially symmetrical with respect to the plane S. For this reason, in the second space 10b, the droplet DL is less affected by the gas flow than when the second aperture 182 is not provided or when the first aperture 181 and the second aperture 182 are provided at asymmetrical positions with respect to the plane S.

[0075] 5.3 Function and Effect According to the EUV light generation device 100 of the present embodiment, similar to the EUV light generation device 100 of Embodiment 1, it is possible to suppress the output of the EUV light 101 from becoming unstable. Further, in the EUV light generation device 100 of the present embodiment, the laser light 90 is irradiated along the longitudinal direction of the debris shield 18. Therefore, when providing a tin recovery mechanism (not shown) for recovering tin from stannane and tin fine particles flowing together with the etching gas, a component that also serves as the laser damper 91 and the tin recovery mechanism can be arranged.

[0076] The present invention has been described by taking embodiments as examples. However, the above embodiments can be changed as appropriate. For example, the debris shield 18 may have a shape different from that of the above embodiment.

[0077] Further, as long as the auxiliary plate 25 is a plate-like member that guides the gas supplied from the second gas supply port 170 to the second opening 182, it may have a shape different from that of the above embodiment. Also, the EUV light generation device 100 of the present invention may not include the auxiliary plate 25. However, it is preferable to provide the auxiliary plate 25 because it can reduce the difference in the amounts of the gas supplied from the first gas supply port 160 and flowing into the second space 10b through the first opening 181 and the gas supplied from the second gas supply port 170 and flowing into the second space 10b through the second opening 182.

[0078] Also, in the above embodiment, the sensors 28a and 28b may be provided on the debris shield 18 in the same manner as in the comparative example. Further, the sensors 28a and 28b may be provided in the chamber 10, and openings for the sensors 28a and 28b to monitor the inside of the second space 10b may be provided on the debris shield 18.

[0079] Also, the gas supplied from the first gas supply port 160 and the gas supplied from the second gas supply port 170 may be different gases. For example, an etching gas may be supplied from the first gas supply port 160 in the same manner as in the above embodiment, and an inert gas may be supplied from the second gas supply port 170. However, it is preferable that the gas supplied from the first gas supply port 160 and the gas supplied from the second gas supply port 170 are of the same type, as in the embodiment.

[0080] Also, in the above embodiment, the gas supply port is composed of the first gas supply port 160 and the second gas supply port 170. However, the present invention is not limited to this, and the gas supply port may be composed of one supply port or three or more supply ports.

[0081] The above description is intended to be illustrative rather than restrictive. Therefore, it will be apparent to those skilled in the art that modifications can be made to the embodiments of the present disclosure without departing from the scope of the claims. It will also be apparent to those skilled in the art that the embodiments of the present disclosure can be used in combination. The terms used throughout this specification and the claims should be construed as "non-limiting" terms unless otherwise specified. For example, terms such as "comprising," "having," "including," and "containing" should be construed as not excluding the presence of components other than those described. Also, the modifier "one" should be construed to mean "at least one" or "one or more." Also, the term "at least one of A, B, and C" should be construed as "A," "B," "C," "A + B," "A + C," "B + C," or "A + B + C," and further construed to include combinations with those other than "A," "B," and "C."

Claims

1. A chamber that generates extreme ultraviolet light by irradiating a target substance supplied to a plasma generation region in an internal space with a laser beam, A target supply unit that supplies droplets of the target substance toward the plasma generation region, A condenser mirror that is disposed in the internal space and condenses the extreme ultraviolet light, A first opening and a second opening are provided through which the extreme ultraviolet light passes from the plasma generation region toward the condenser mirror, and a debris shield that surrounds the plasma generation region, A gas supply port that is provided in the chamber and supplies gas to the internal space, An exhaust port that exhausts gas in a space surrounded by the debris shield, comprising At least a part of the second opening is provided at a position symmetric to at least a part of the first opening with respect to a plane including the orbit of the laser beam and the orbit of the droplet, The gas in the internal space flows into the space from the first opening and the second opening Extreme ultraviolet light generating device.

2. The extreme ultraviolet light generating device according to claim 1, The debris shield is cylindrical with its longitudinal direction extending in the gas exhaust direction.

3. The extreme ultraviolet light generating device according to claim 2, The target supply unit supplies the droplets along the longitudinal direction.

4. The extreme ultraviolet light generating device according to claim 2, The laser beam is irradiated along the longitudinal direction.

5. The extreme ultraviolet light generating device according to claim 2, The inner diameter of the debris shield is 90 mm or more and 160 mm or less.

6. The extreme ultraviolet light generating device according to claim 1, wherein the first opening and the second opening are mirror-symmetric with the plane as the mirror plane.

7. The extreme ultraviolet light generating device according to claim 1, wherein the same amount of the gas flows in from the first opening and the second opening.

8. The extreme ultraviolet light generating device according to claim 1, wherein the first opening and the second opening have the same area.

9. The extreme ultraviolet light generating device according to claim 1, wherein the first opening and the second opening have the same shape.

10. The extreme ultraviolet light generating device according to claim 1, wherein the first opening and the second opening are larger in area than other openings provided in the debris shield except for the exhaust port.

11. The extreme ultraviolet light generating device according to claim 1, wherein in a direction perpendicular to the plane, at least 95% of the first opening and the second opening overlap each other.

12. The extreme ultraviolet light generating device according to claim 1, wherein the gas supply port includes a first gas supply port provided on the side where the first opening is located with respect to the plane, and a second gas supply port provided on the side where the second opening is located with respect to the plane.

13. The extreme ultraviolet light generating device according to claim 12, wherein at least a part of the first gas supply port and at least a part of the second gas supply port are provided at symmetric positions with respect to the plane.

14. The extreme ultraviolet light generating device according to claim 12, wherein It is provided with an auxiliary plate that guides the gas supplied from the second gas supply port to the second opening. The condenser mirror guides the gas supplied from the first gas supply port to the first opening.

15. An extreme ultraviolet light generating device according to claim 14, At least a part of the auxiliary plate is provided at a position symmetric to the condenser mirror with respect to the plane.

16. An extreme ultraviolet light generating device according to claim 15, The auxiliary plate has a concave shape that is concave in a direction symmetric to the direction in which the condenser mirror is concave with respect to the plane.

17. An extreme ultraviolet light generating device according to claim 16, The auxiliary plate has the same shape as the condenser mirror.

18. An extreme ultraviolet light generating device according to claim 14, A sensor for observing the state inside the space is attached to the auxiliary plate through the second opening.

19. A chamber that generates extreme ultraviolet light by irradiating a target substance supplied to a plasma generation region in an internal space with a laser beam, A target supply unit that supplies droplets of the target substance toward the plasma generation region, A condenser mirror that is disposed in the internal space and condenses the extreme ultraviolet light, A first opening and a second opening through which the extreme ultraviolet light passes from the plasma generation region toward the condenser mirror are provided, and a debris shield that surrounds the plasma generation region, A gas supply port that is provided in the chamber and supplies gas to the internal space, An exhaust port that exhausts the gas in the space surrounded by the debris shield, and At least a part of the second opening is provided at a position symmetric to at least a part of the first opening with respect to a plane including the orbit of the laser beam and the orbit of the droplet. The gas in the internal space outputs the extreme ultraviolet light to an exposure apparatus by an extreme ultraviolet light generating device that flows into the space from the first opening and the second opening. In order to manufacture an electronic device, the extreme ultraviolet light is exposed onto a photosensitive substrate in the exposure apparatus. A method for manufacturing an electronic device including this.

20. A chamber that generates extreme ultraviolet light by irradiating a target substance supplied to a plasma generation region in an internal space with a laser beam, A target supply unit that supplies droplets of the target substance toward the plasma generation region, A condenser mirror that is disposed in the internal space and condenses the extreme ultraviolet light, A first opening and a second opening through which the extreme ultraviolet light passes from the plasma generation region toward the condenser mirror are provided, and a debris shield that surrounds the plasma generation region, A gas supply port that is provided in the chamber and supplies gas to the internal space, An exhaust port that exhausts the gas in the space surrounded by the debris shield, Comprising At least a part of the second opening is provided at a position symmetric to at least a part of the first opening with respect to a plane including the orbit of the laser beam and the orbit of the droplet. The gas in the internal space irradiates a mask with the extreme ultraviolet light generated by the extreme ultraviolet light generating device that flows into the space from the first opening and the second opening to inspect defects of the mask. The mask is selected using the result of the inspection. The pattern formed on the selected mask is exposed and transferred onto a photosensitive substrate. A method for manufacturing an electronic device including this.

Images