Apparatus for generating EUV radiation, and method

Abstract

The invention relates to an apparatus (10) for generating EUV radiation. The apparatus (10) has a vacuum chamber (12) in which a target material (22) for generating the EUV radiation can be arranged, a laser beam source device (14) for generating laser radiation (24, 28, 32), a beam directing device (16) for directing the laser radiation (24, 28, 32) onto the vacuum chamber (12), a detection device (18) for detecting a position of the target material (22) in the vacuum chamber (12), and a control device (20) which is designed to control the beam directing device (16) depending on the position, detected by means of the detection device (18), of the target material (22) in the vacuum chamber (12), for the purpose of directing the laser radiation (24, 28, 32) onto the target material (22). The detection device (18) is designed to generate an illumination beam (40) for illuminating the target material (22) and to detect the position of the target material (22) in the vacuum chamber (12) on the basis of a portion (46) of the illumination beam (40) reflected by the target material (22).

Description

[0001] Device for generating EUV radiation and method

[0002] Description

[0003] The invention relates to a device for generating EUV radiation and a method for operating such a device.

[0004] Extreme ultraviolet (EUV) radiation enables the precise and highly accurate imaging of fine structures, which is why EUV radiation is frequently used in lithography, often referred to as E-UV lithography. Due to the advantage of precise and highly accurate imaging of fine structures, EUV lithography is typically used for the production of microchips.

[0005] In EUV lithography, EUV radiation is often generated by directing laser radiation onto a target material, for example, in the form of a tin droplet. Upon impact with the target material, the laser radiation converts it into a plasma state, thus generating EUV radiation.

[0006] The laser radiation can consist of a pre-pulse and a main pulse following the pre-pulse. The pre-pulse can prepare the target material for the main pulse, ensuring that as much of the main pulse as possible is converted into EUV radiation upon impact. A portion of the pre-pulse reflected by the target material can be used to determine its position. Based on this position, subsequent pre-pulses and main pulses can be directed onto the target material. This allows for the compensation of temporal variations in the system generating the pre-pulses and main pulses. These temporal variations can be induced, for example, by thermal deformation.

[0007] The invention aims to provide a device for generating EUV radiation and a method for operating such a device, each enabling more efficient generation of EUV radiation. The invention achieves this objective by providing a device for generating EUV radiation with the features of claim 1 and a method with the features of claim 8. Advantageous further developments and / or embodiments of the invention are described in the dependent claims.

[0008] An inventive device for generating EUV radiation comprises a vacuum chamber, a laser beam source, a beam guidance device, a detection device, and a control device. A target material for generating EUV radiation can be arranged in the vacuum chamber. The laser beam source is configured to generate laser radiation. The beam guidance device is configured to direct the laser radiation onto the vacuum chamber. The detection device is configured to detect the position of the target material in the vacuum chamber. The control device is configured to control the beam guidance device, depending on the position of the target material in the vacuum chamber detected by the detection device, for the purpose of directing the laser radiation onto the target material.The detection device is designed to generate an illumination beam for illuminating the target material and to detect the position of the target material in the vacuum chamber based on a portion of the illumination beam reflected by the target material.

[0009] Advantageously, the position of the target material in the vacuum chamber can be detected with exceptional precision using the illumination beam. The illumination beam allows for optimal fulfillment of both temporal and spatial illumination requirements. In particular, separating the task of illuminating the target material for position detection from the task of irradiating the target material to generate EUV radiation enables the provision of an illumination beam specifically suited for position detection. In other words, separating these tasks allows the parameters for the laser radiation and the illumination beam to be optimally adjusted independently for their respective functions.This allows for precise detection of the target material's position within the vacuum chamber. Consequently, the control unit directs the laser radiation with exceptional accuracy onto the target material using the beam guidance system, thus enabling highly efficient generation of EUV radiation. In other words, by directing the laser radiation with high precision onto the target material, a high yield of EUV radiation can be achieved.

[0010] Another aspect of the invention is that, by using the illumination beam, a temporal change in the path of the laser radiation can be detected and compensated for, at least partially. This temporal change in the path of the laser radiation can occur, for example, as a result of dynamic acceleration and the resulting relative motion, thermal deformations, and / or thermally induced changes in the optical densities of glasses.

[0011] The vacuum chamber can have an interior space. The target material can be arranged within this interior space. The vacuum chamber can be in a vacuum state. In this vacuum state, a vacuum can exist within the interior of the vacuum chamber.

[0012] The target material can be a metal, for example tin. The target material can be in the form of droplets, for example tin droplets.

[0013] The target material can move within the vacuum chamber. For example, gravity can act on the target material, causing it to move within the vacuum chamber. The detection device can be configured to detect the movement of the target material. The control device can be configured to control the beam guidance device, based on the movement of the target material within the vacuum chamber as detected by the detection device, for the purpose of directing the laser beam onto the target material.

[0014] The laser radiation can strike the target material and thereby convert it into a plasma state. During this conversion, EUV radiation can be generated. In other words, EUV radiation can be produced when the target material is irradiated with laser radiation. Put another way, the laser radiation can be designed to generate EUV radiation upon striking the target material. The laser radiation can also be designed to influence the target material, for example, by heating, expanding, vaporizing, ionizing, and / or converting it into a plasma state.

[0015] The laser beam source device can have a single laser beam source for generating a laser beam. This single laser beam source can be a solid-state laser or a gas laser, in particular a CO2 laser.

[0016] Alternatively, the laser beam source device can have a first laser beam source for generating a laser beam and a second laser beam source for generating a laser beam. The first laser beam source can be a solid-state laser. The second laser beam source can be a gas laser, in particular a CO2 laser.

[0017] The laser beam from the first laser source and the laser beam from the second laser source can differ in their power and / or wavelength. The wavelength of the laser beam from the first laser source can range from 1 pm (micrometer) to 3 pm. The wavelength of the laser beam from the second laser source can range from 1.5 pm to 2.5 pm or from 10 pm to 11 pm. In particular, the wavelength of the laser beam from the second laser source can be 10.6 pm.

[0018] The power of the laser beam from the first laser source and / or the power of the laser beam from the second laser source can be at least 200 W (watts), at least 500 W, at least 1 kW (kilowatt), or at least 10 kW. The power of the laser beam from the first laser source can be less than the power of the laser beam from the second laser source.

[0019] The laser radiation from the laser beam source device can include the laser beam from the first laser beam source and the laser beam from the second laser beam source.

[0020] The beam path of the laser beam from the first laser source and the beam path of the laser beam from the second laser source can be different or at least partially identical. The beam guidance device can be configured to direct the laser radiation from the laser source device to the target material. The beam guidance device can include optical components, in particular lenses and / or mirrors.

[0021] Preferably, the beam guidance device can include at least one controllable mirror, for example, a galvanometer mirror. The controllable mirror allows the beam path of the laser radiation through the vacuum chamber to be changed, in particular adjusted. The control device can be configured to control the controllable mirror based on the position of the target material in the vacuum chamber, as detected by the detection device, for the purpose of directing the laser radiation onto the target material.

[0022] Preferably, the detection device can be configured to generate the illumination beam, in particular only, for illuminating the target material.

[0023] The detection device may include an illumination beam source for generating the illumination beam. The illumination beam source may be a diode laser, for example a vertical cavity surface emitting laser (VCSEL), a fiber laser, a disk laser, or a lamp-pumped rod laser.

[0024] The illumination beam can have parameters that are optimal for detecting the position of the target material. The illumination beam can be configured to have essentially no effect on the target material, for example, by not substantially heating, expanding, vaporizing, ionizing, and / or bringing the target material into a plasma state, particularly when the illumination beam strikes the target material. In other words, the illumination beam can be designed to be unsuitable for affecting the target material. Specifically, the illumination beam can be configured such that no EUV radiation is generated when the illumination beam strikes the target material.

[0025] The illumination beam can have a maximum power of 30 W. For example, the power of the illumination beam can range from 0.5 W to 30 W. The illumination beam can have a wavelength of 976 nm (nanometers), 1030 nm, 1064 nm, or approximately 1500 nm.

[0026] The diameter of the illumination beam on the target material can be larger than the diameter of the laser radiation on the target material.

[0027] The diameter of the illumination beam on the target material can be less than or equal to 1 mm (millimeter).

[0028] The illumination beam can exhibit a top hat-shaped intensity distribution in a cross-section.

[0029] The illumination beam can be a beam with low coherence. The illumination beam can be a multimode beam.

[0030] The detection device can include a detector for detecting the portion of the illumination beam reflected by the target material. The detector can be configured as a camera or a quadrant diode, in particular a 4-quadrant diode.

[0031] The control unit can be a computer, a calculator, or a microcontroller.

[0032] The device can contain the target material. The target material can be arranged in the vacuum chamber.

[0033] In a further development of the device, the detection unit is configured to detect the velocity, acceleration, and / or direction of movement of the target material in the vacuum chamber based on the portion of the illumination beam reflected by the target material. The control unit is configured to actuate the beam guidance unit, depending on the velocity and / or direction of movement of the target material detected by the detection unit in the vacuum chamber, for the purpose of directing the laser radiation onto the target material. This allows the laser radiation to be precisely directed onto the target material by the beam guidance unit if the target material is moving within the vacuum chamber.The detection of the velocity and / or direction of motion of the target material in the vacuum chamber can be achieved by detecting the position of the target material in the vacuum chamber twice, wherein each detection comprises an initial detection of the position followed by a second detection at a later time interval. The detection of the acceleration of the target material in the vacuum chamber can be achieved by detecting the position of the target material in the vacuum chamber three times, wherein each detection comprises an initial detection of the position, a second detection at a later time interval, and a third detection at a later time interval.

[0034] The control unit can determine a target position of the target material based on the detected position, velocity, acceleration, and / or direction of movement of the target material at the moment the laser radiation strikes the target material. The control unit can be configured to actuate the beam guidance device, depending on the determined target position, for the purpose of directing the laser radiation onto the target material.

[0035] In a further development of the device, the laser radiation is pulsed laser radiation with pre-pulses and main pulses. Each main pulse is preceded, particularly shortly before, by a pre-pulse. The control unit is designed to control the beam guidance device, depending on the position of the target material in the vacuum chamber as detected by the detection device, for the purpose of directing the pre-pulse and / or the main pulse onto the target material. By using pre-pulses and main pulses, a particularly efficient generation of EUV radiation can be achieved.

[0036] For example, each pre-pulse can prepare the target material for the onset of the main pulse. In particular, each pre-pulse can affect the target material, for example by heating, expanding, vaporizing, ionizing, and / or converting the target material into a plasma state.

[0037] The main pulses and the pre-pulses can form a pulse sequence of alternating main pulses and pre-pulses. A pre-pulse beam path and a main pulse beam path can differ from each other or at least be segmentally identical.

[0038] The time interval between each main pulse and a preceding pre-pulse can be less than the time interval between the main pulse and the following pre-pulse.

[0039] The main pulse can convert a larger proportion of the target material into the plasma state than the pre-pulse.

[0040] The pre-pulse may have a lower power output than the main pulse.

[0041] The wavelength of the pre-pulses and the wavelength of the main pulses can be the same or different from each other.

[0042] The single laser beam source of the laser beam source device can be suitable for generating the pre-pulses and the main pulses.

[0043] Alternatively, the first laser beam source of the laser beam source device can be used to generate the pre-pulse and the second laser beam source of the laser beam source device can be used to generate the main pulse.

[0044] The wavelength of the pre-pulse can be in the range of 1 pm to 1.1 pm. The wavelength of the main pulse can be in the range of 10 pm to 11 pm. Preferably, the wavelength of the main pulse can be 10.6 pm.

[0045] In a further development of the device, the control unit is designed to synchronize the detection of the target material's position in the vacuum chamber with the generation of the pre-pulses and / or main pulses using the laser beam source. This avoids unnecessary detection of the target material's position.

[0046] The detection of the target material's position in the vacuum chamber can be triggered by the generation of pre-pulses and / or main pulses. In other words, the generation of pre-pulses and / or main pulses can initiate, or specifically trigger, the detection of the target material's position.

[0047] For example, the control unit can be configured to control the detection device in such a way that the detection of the target material's position in the vacuum chamber occurs before and / or simultaneously with the impact of a pre-pulse on the target material. This allows the main pulse to be directed with particular precision onto the target material.

[0048] The illumination beam can be a pulsed illumination beam. The pulse frequency of the illumination beam can be equal to the pulse frequency of the pre-pulses and / or the pulse frequency of the main pulses.

[0049] In a further development of the device, the polarization direction of the illumination beam of the detection device differs from the polarization direction of the pre-pulses and / or the polarization direction of the main pulses. This allows for a particularly simple spatial combination and / or separation of the illumination beam from the pre-pulses and / or the main pulses.

[0050] The device may include a polarizer for combining and / or separating the illumination beam from the pre-pulses and / or the main pulses.

[0051] In a further development of the device, a wavelength value of the illumination beam of the detection device differs from a wavelength value of the laser radiation of the laser beam source device. This allows for particularly easy spatial combination and / or separation of the illumination beam from the laser radiation. Advantageously, this makes it particularly easy to eliminate interference when the laser radiation and illumination beam are superimposed. This reduces or completely eliminates the influence of the laser radiation on the detection of the target material's position.

[0052] The device can include a wavelength filter for combining and / or separating the illumination beam from the laser radiation. In a further development of the device, the beam path of the illumination beam in the detection device and the beam path of the laser radiation in the laser beam source device are at least partially identical. This allows the device to be designed to be particularly compact.

[0053] The device can include a beam combiner that combines the illumination beam and the laser radiation, in particular such that the beam path of the illumination beam and the beam path of the laser radiation are at least partially the same.

[0054] The beam combiner can be designed, for example, as a polarizer, a wavelength filter and / or a beam splitter.

[0055] A method according to the invention is designed for operating a previously described device. The method comprises the following steps: arranging the target material for generating EUV radiation in the vacuum chamber; illuminating the target material with the illumination beam of the detection device; detecting the position of the target material in the vacuum chamber based on the portion of the illumination beam reflected by the target material; generating the laser radiation by means of the laser beam source device; directing the laser radiation onto the target material by controlling the beam guidance device depending on the detected position of the target material in the vacuum chamber.

[0056] In a further development of the process, the generation of laser radiation using the laser beam source device includes the generation of pre-pulses and main pulses. Each main pulse is preceded by a pre-pulse. Directing the laser radiation onto the target material involves directing the pre-pulses and / or the main pulses onto the target material by controlling the beam guidance device depending on the detected position of the target material in the vacuum chamber.

[0057] In a further development of the method, the steps of detecting the position of the target material and generating the pre-pulses and / or the main pulses are temporally coordinated. In this further development of the method, the position of the target material is detected immediately before the generation of each pre-pulse and / or main pulse.

[0058] Further advantages and advantageous embodiments of the invention can be seen from the figures, their description, and the claims. All features disclosed in the figures, their description, and the claims can be essential to the invention, both individually and in any combination. The figures show:

[0059] Fig. 1 shows a schematic representation of a device for generating EUV radiation, and

[0060] Fig. 2 shows a schematic sequence of a method for operating the device of Fig. 1.

[0061] Fig. 1 shows a device 10 for generating EUV radiation. The device 10 has a vacuum chamber 12, a laser beam source device 14, a beam guidance device 16, a detection device 18 and a control device 20 in the form of a computer.

[0062] Vacuum chamber 12 has an interior. A vacuum exists within vacuum chamber 12. Therefore, vacuum chamber 12 is in a vacuum state.

[0063] A target material 22 in the form of a tin droplet is arranged in the interior. The target material 22 is suitable for generating EUV radiation.

[0064] The laser beam source device 14 is designed to generate laser radiation 24. The laser beam source device 14 has a first laser beam source 26 for generating a laser beam 28 and a second laser beam source 30 for generating a laser beam 32.

[0065] In an alternative embodiment not shown, the laser beam source device has more than two laser beam sources, for example three or four laser beam sources, or only a single laser beam source. The first laser beam source 26 is a solid-state laser in the form of a fiber laser. The wavelength of the laser beam 28 of the first laser beam source 26 can be 1064 nm. The power of the laser beam 28 of the first laser beam source 26 can be at least 500 W.

[0066] The second laser beam source 30 is a gas laser in the form of a CCh laser. The wavelength of the laser beam 32 of the second laser beam source 30 can be 10.6 pm. The power of the laser beam 32 of the second laser beam source 30 can be at least 10 kW.

[0067] Thus, the laser radiation 24 of the laser beam source device 14 has the laser beam 28 of the first laser beam source 26 and the laser beam 32 of the second laser beam source 30.

[0068] The beam path of the laser beam 28 of the first laser beam source 26 and the beam path of the laser beam 32 of the second laser beam source 30 differ from each other.

[0069] The beam guidance device 16 consists of a plurality of optical components in the form of mirrors and lenses. The optical components are arranged such that the laser beam 28 from the first laser beam source 26 and the laser beam 32 from the second laser beam source 30 are directed from the laser beam source device 14 onto the vacuum chamber 12. In other words, the beam guidance device 16 is configured to direct the laser radiation 24 from the laser beam source device 14 onto the target material 22.

[0070] The beam guidance device 16 has two controllable mirrors 34 in the form of galvanometer mirrors for changing the beam path of the laser beam 28 of the first laser beam source 26. The control device 20 is designed to control the two controllable mirrors 34 for changing the beam path of the laser beam 28 of the first laser beam source 26, in particular for the purpose of directing the laser beam 28 of the first laser beam source 26 onto the target material 22.

[0071] The beam guidance device 16 has two further controllable mirrors 36 in the form of galvanometer mirrors for changing the beam path of the laser beam 32 of the second laser beam source 30. The control device 20 is designed to control the two further controllable mirrors 36 for changing the beam path of the laser beam 32 of the second laser beam source 30, in particular for the purpose of directing the laser beam 32 of the second laser beam source 30 onto the target material 22.

[0072] The detection device 18 has an illumination beam source 38 for generating an illumination beam 40. The illumination beam source 38 is a diode laser. The illumination beam source 38 is a continuous-wave laser. The illumination beam 40 has a wavelength of 976 nm. The power of the illumination beam 40 can be less than 30 W. The illumination beam 40 can exhibit a tophat-shaped intensity distribution in a cross-section.

[0073] The illumination beam 40 is generated by the detection device 18, specifically solely for illuminating the target material 22. The illumination beam 40 is designed not to affect the target material 22, for example, by heating, expanding, vaporizing, ionizing, and / or converting the target material 22 into a plasma state when the illumination beam 40 strikes the target material 22. In particular, the illumination beam 40 does not generate EUV radiation when it strikes the target material 22.

[0074] The detection device 18 has an optical switch 42 for switching the illumination beam 40. The optical switch 42 is an electro-optic modulator.

[0075] The detection device 18 has a scraper mirror 44. The scraper mirror 44 has a hole for guiding the illumination beam 40. The hole can be located centrally. After being generated by the illumination beam source 38, the illumination beam 40 is guided through the hole of the scraper mirror 44.

[0076] When the illumination beam 40 strikes the target material 22, a portion 46 of the illumination beam 40 is reflected by the target material 22. In Fig. 1, the reflected portion 46 of the illumination beam 40 is shown as a dashed line.

[0077] The reflected portion 46 of the illumination beam 40 strikes the scraper mirror 44 and is reflected by the scraper mirror 44 onto a detector 48 of the detection device 18. In the illustrated embodiment, the detector is, by way of example, a 4-quadrant diode. Based on the portion of the illumination beam 40 reflected by the target material 22, the detection device 18 detects a position of the target material 22 in the vacuum chamber 12.

[0078] In an alternative embodiment not shown, the device may include a polarizer and an A / 4 plate instead of the scraper mirror. The A / 4 plate may be positioned downstream of the polarizer in the direction of propagation of the illumination beam. The illumination beam may be linearly polarized. The illumination beam generated by the illumination source may pass through the polarizer and the A / 4 plate, becoming circularly polarized after passing through the A / 4 plate. The portion of the illumination beam reflected by the target material may be circularly polarized and linearly polarized after passing through the A / 4 plate. The linear polarization of the reflected portion of the illumination beam may be orthogonal to the linear polarization of the illumination beam before passing through the A / 4 plate.This allows the reflected portion of the illumination beam to be directed onto the detector using the polarizer.

[0079] The beam-guiding device 16 has a wavelength filter 50. The laser beam 28 from the first laser beam source 26 strikes the wavelength filter 50. The illumination beam 40 strikes the wavelength filter 50 after passing through the scraper mirror 44. The wavelength filter 50 can be configured as a Bragg mirror. The wavelength filter 50 can have a reflectance of over 95% for the wavelength of the illumination beam 40 and a reflectance of less than 5% for the wavelength of the laser beam 28 from the first laser beam source 26. This allows the illumination beam 40 to be deflected by means of the wavelength filter 50, while the laser beam 28 from the first laser beam source 26 remains unaffected.

[0080] After passing through the wavelength filter 50, the beam path of the illumination beam 40 and the beam path of the laser beam 28 of the first laser beam source 26 to the target material 22 are the same.

[0081] In an alternative embodiment not shown, the device can have a polarizer instead of the wavelength filter for spatially combining the illumination beam with the laser beam of the first laser source. In the illustrated embodiment of Fig. 1, the illumination beam 40 and the laser beam 28 of the first laser source 26 strike the two controllable mirrors 34 after passing through the wavelength filter 50. By arranging the two controllable mirrors 34 in the direction of propagation of the illumination beam 40 after the wavelength filter 50, the illumination beam 40 and the laser beam 28 of the first laser source 26 can be adjusted simultaneously by means of the two controllable mirrors 34. Advantageously, this allows the illumination beam 40 to be adjusted only once relative to the laser beam 28 of the first laser source 26.

[0082] After passing through the two controllable mirrors 34, the illumination beam 40 and the laser beam 28 of the first laser beam source 26 strike the target material 22. The beam diameter of the illumination beam 40 on the target material 22 is larger than the beam diameter of the laser beam 28 of the first laser beam source 26 on the target material 22.

[0083] The laser beam 28 of the first laser source 26 and the laser beam 32 of the second laser source 30 are pulsed laser beams 28, 32. The pulses of laser beam 28 from the first laser source 26 and the pulses of laser beam 32 from the second laser source 30 alternately strike the target material 22. In other words, the pulses of laser beam 28 from the first laser source 26 and the pulses of laser beam 32 from the second laser source 30 form a pulse sequence for the target material 22.

[0084] The time interval between each pulse of the second laser beam source 30 and a pulse of the first laser beam source 26 that precedes the pulse of the second laser beam source 30 is smaller than the time interval between the pulse of the second laser beam source 30 and a pulse of the first laser beam source 26 that follows the pulse of the second laser beam source 30. Therefore, the pulses of the first laser beam source 26 are pre-pulses for the target material 22, and the pulses of the second laser beam source 30 are main pulses for the target material 22. In other words, a pulse of the first laser beam source 26 arrives at the target material 22 shortly before a pulse of the second laser beam source 30 arrives.

[0085] Each pre-pulse has a lower power than the main pulse. Each pre-pulse of the first laser beam source 26 prepares the target material 22 for the impact of a main pulse. This allows the subsequent main pulse to convert the target material 22 into a plasma state particularly efficiently, thereby generating EUV radiation, which is why EUV radiation is produced with high efficiency.

[0086] The control device 20 is designed to coordinate the detection of the position of the target material 22 in the vacuum chamber 12 with the generation of the pre-pulses and the main pulses by means of the laser beam source device 14.

[0087] In the illustrated embodiment, the control unit 20 detects the generation of a pre-pulse and subsequently triggers the detection of the target material 22's position. The control unit 20 controls the detection unit 18 such that the detection of the target material 22's position in the vacuum chamber occurs simultaneously with the pre-pulse striking the target material 22.

[0088] When the detection device 18 is activated by the control device 20 to detect the position of the target material 22, the detection device 18 switches the optical switch 42 such that the illumination beam 40 passes through the optical switch 42 and strikes the target material 22. The detection device 18 detects the position of the target material 22 in the vacuum chamber 12 based on the portion of the illumination beam 40 reflected by the target material 22.

[0089] The control device 20 controls the controllable mirrors 34 and the further controllable mirrors 36 in such a way that the laser beam 28 of the first laser beam source 26 and the laser beam 32 of the second laser beam source 30 are directed onto the target material 22.

[0090] Fig. 2 shows an exemplary sequence of a method for operating a previously described device from Fig. 1.

[0091] The method comprises the following steps: a) arranging the target material 22 for generating EUV radiation in the vacuum chamber 12; b) illuminating the target material 22 with the illumination beam 40 of the detection device 18; c) detecting the position of the target material 22 in the vacuum chamber 12 based on the portion of the illumination beam 40 reflected by the target material 22; d) generating the laser radiation 24 using the laser beam source device 14 by generating pre-pulses and main pulses, wherein each main pulse is preceded in time by a pre-pulse, and wherein the detection of the position of the target material 22 in step c) and the generation of the laser radiation 24 are temporally synchronized; and e) Directing the laser radiation 24 onto the target material 22 by controlling the beam guidance device 16 depending on the detected position of the target material 22 in the vacuum chamber 12.

Claims

Patent claims 1. Device (10) for generating EU radiation, comprising: a vacuum chamber (12) in which a target material (22) for generating EUV radiation can be arranged, a laser beam source device (14) for generating laser radiation (24, 28, 32), a beam guidance device (16) for directing the laser radiation (24, 28, 32) onto the vacuum chamber (12), a detection device (18) for detecting a position of the target material (22) in the vacuum chamber (12), and a control device (20) configured to control the beam guidance device (16) depending on the position of the target material (22) in the vacuum chamber (12) detected by the detection device (18) for the purpose of directing the laser radiation (24, 28, 32). to target the target material (22), wherein the detection device (18) is designed toto generate an illumination beam (40) for illuminating the target material (22) and to detect the position of the target material (22) in the vacuum chamber (12) based on a portion (46) of the illumination beam (40) reflected by the target material (22).

2. Device (10) according to claim 1, wherein the detection device (18) is configured to detect a velocity, an acceleration and / or a direction of movement of the target material (22) in the vacuum chamber (12) based on the portion (46) of the illumination beam (40) reflected by the target material (22), wherein the control device (20) is configured to control the beam guidance device (16) depending on the velocity and / or direction of movement of the target material (22) in the vacuum chamber (12) detected by the detection device (18) for the purpose of guiding the laser radiation (24, 28, 32) onto the target material (22).

3. Device (10) according to one of the preceding claims, wherein the laser radiation (24, 28, 32) is a pulsed laser radiation with pre-pulses and main pulses, wherein each main pulse is preceded in time by a pre-pulse, wherein the control device (20) is configured to control the beam guidance device (16) depending on the position of the target material (22) in the vacuum chamber (12) detected by means of the detection device (18) for the purpose of directing the pre-pulse and / or the main pulse onto the target material (22).

4. Device (10) according to claim 3, wherein the control device (20) is configured to coordinate the detection of the position of the target material (22) in the vacuum chamber (12) and the generation of the pre-pulses and / or the main pulses by means of the laser beam source device (14) in time.

5. Device (10) according to one of the preceding claims 3 or 4, wherein a polarization direction of a polarization of the illumination beam (40) of the detection device (18) differs from a polarization direction of a polarization of the pre-pulse and / or from a polarization direction of a polarization of the main pulse.

6. Device (10) according to one of the preceding claims, wherein a value of a wavelength of the illumination beam (40) of the detection device (18) differs from a value of a wavelength of the laser radiation (24, 28, 32) of the laser beam source device (14).

7. Device (10) according to one of the preceding claims, wherein a beam path of the illumination beam (40) of the detection device (18) and a beam path of the laser radiation (24, 28, 32) of the laser beam source device (14) are at least sectionally the same.

8. Method for operating a device (10) according to one of the preceding claims, wherein the method comprises the steps: Arranging the target material (22) to generate EUV radiation in the vacuum chamber (12), Illuminating the target material (22) with the illumination beam (40) of the detection device (18), Detecting the position of the target material (22) in the vacuum chamber (12) based on the fraction (46) of the illumination beam (40) reflected by the target material (22), Generating the laser radiation (24, 28, 32) using the laser beam source device (14), and Directing the laser radiation (24, 28, 32) onto the target material (22) by controlling the beam guidance device (16) depending on the detected position of the target material (22) in the vacuum chamber (12).

9. Method according to claim 8, wherein the generation of the laser radiation (24, 28, 32) by means of the laser beam source device (14) comprises generating pre-pulses and main pulses, wherein each main pulse is preceded in time by a pre-pulse, wherein the directing of the laser radiation (24, 28, 32) onto the target material (22) comprises directing the pre-pulses and / or the main pulses onto the target material (22) by controlling the beam guidance device (16) depending on the detected position of the target material (22) in the vacuum chamber (12).

10. Method according to claim 9, wherein the steps of detecting the position of the target material (22) and generating the pre-pulse and / or the main pulse are time-coordinated.

11. Method according to claim 10, wherein the position of the target material (22) is detected immediately before the generation of a respective pre-pulse of the pre-pulses and / or a respective main pulse of the main pulses.

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