Ion isolation device and method for protecting off-axis EUV collecting mirror based on electromagnetic field

Abstract

The invention discloses an ion isolation device for protecting an off-axis EUV collecting mirror based on an electromagnetic field. The ion isolation device comprises an EUV light source system, a conical cavity, a direct-current voltage generator, an electrode plate, a permanent magnet, a Mo / Si multilayer film collecting mirror, an EUV camera, a Faraday cup and a computer, the EUV light source system is arranged in a vacuum cavity, provides enough energy through laser, excites a target material, generates plasma radiation EUV, and generates debris and high-energy ions along with the generation of the debris and the high-energy ions; the conical cavity isolates the vacuum cavity from the electrode plate and maintains the air pressure in the cavity stable; the direct-current voltage generator provides voltage for the electrode plates; the electrode plate generates an electric field; the permanent magnet generates a magnetic field, and the electric field and the magnetic field act on high-energy ions, so that the ions are deflected, an isolation effect is achieved, and the Mo / Si multilayer film collecting mirror is protected; the Mo / Si multilayer film collecting mirror focuses an EUV light spot of plasma radiation to an IF point; the EUV camera is used for recording the imaging of an IF point and the shape and size of a light spot; the Faraday cup is used for recording the beam intensity of the ion debris; the computer is used for recording, analyzing and calculating images and signals of the EUV camera and the Faraday cup, adjusting electronic controls such as the displacement table, isolating high-energy ions, preventing the high-energy ions from directly damaging the collecting mirror, and effectively prolonging the service life of the EUV collecting mirror.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of extreme ultraviolet lithography technology and optical element protection, and particularly relates to an ion isolation device and method for protecting an off-axis extreme ultraviolet (EUV) collection mirror based on an electromagnetic field. BACKGROUND

[0002] Extreme ultraviolet light (EUVL) is the main light source for modern chip production below 7 nm. At present, the mainstream EUV lithography machine in the world uses a carbon dioxide laser to excite a tin droplet target to generate plasma. EUV light is reflected, collected and used by a Mo / Si multilayer film collection mirror. At present, the plasma generated by tin, lithium and xenon under laser excitation has a good bandwidth in the spectral curve. Among them, tin as a liquid target material will produce debris, including high-energy ions, neutral particles, particles and molten droplets, after being excited by a laser. Xenon as a gas target material will produce high-energy ion debris after being excited by a laser. These debris will cause damage to the Mo / Si multilayer film, so it is of great significance to isolate high-energy particles and protect the collection mirror.

[0003] However, most of the current methods for removing high-energy ions are based on EUV light source devices using tin as a liquid target material. For example, Harilal S S and others of the University of California Energy Research Center studied the effect of buffer gas and magnetic field combination on ion debris in tin plasma EUV light source, which to some extent prolonged the service life of the collection mirror and slowed down the impact of high-energy ion debris on the collection mirror (Harilal S S, Applied Physics B, 2007, 86(3): 547-553.). However, when xenon is used as a gas target material, only high-energy ions will be generated at the same time as the extreme ultraviolet light is generated. Focusing on the development of Xe-LPP extreme ultraviolet light source, the use of environmental gas will increase the absorption rate of EUV, and a single magnetic field cannot completely isolate high-energy ions, so it cannot effectively protect the collection mirror.

[0004] Therefore, it is urgent to develop a new ion isolation technology suitable for xenon target EUV light source system, which can effectively deflect and capture high-energy ions without affecting the transmission of EUV light, and achieve comprehensive protection of the collection mirror. SUMMARY

[0005] In order to solve the problems of the prior art, such as the bombardment damage of high-energy ions to Mo / Si multilayer film collector mirrors in the LPP-EUV light source of gas targets such as xenon (Xe), the incomplete protection of a single magnetic field, and the absorption of EUV light caused by the introduction of buffer gas, the present application provides an ion isolation device for protecting off-axis EUV collector mirrors based on electromagnetic fields, which changes the motion trajectory of high-energy ions by using electromagnetic fields to protect the collector mirrors, and realizes efficient and active deflection and isolation of high-energy ions without affecting the transmission of EUV light, thereby significantly prolonging the service life of the collector mirrors and improving the stability and availability of the EUV light source.

[0006] The technical solutions adopted by the present application are as follows: An ion isolation device for protecting off-axis EUV collector mirrors based on electromagnetic fields, characterized in that it comprises, in sequence along the transmission direction of the light path: An EUV light source system for generating extreme ultraviolet light and accompanying high-energy ions; A conical chamber with an entrance end optically connected to the vacuum chamber of the EUV light source system through a pinhole; An electromagnetic deflection assembly arranged inside the conical chamber for forming a composite electromagnetic field, the electromagnetic deflection assembly being composed of parallel and opposite electrode plates and a permanent magnet generating a transverse magnetic field, and the magnetic field generated by the permanent magnet being perpendicular to the electric field generated between the electrode plates, thereby forming an electromagnetic field region for composite deflection of high-energy ions; A Mo / Si multilayer film collector mirror arranged at the rear end of the light outlet of the conical chamber for receiving and focusing the extreme ultraviolet light passing through the electromagnetic deflection region; Wherein, the electrode plates are electrically connected to a direct current voltage generator to generate an electric field, and the motion trajectory of the high-energy ions is deflected when passing through the electromagnetic field region and is absorbed by the inner wall of the conical chamber or the electrode plates, while the extreme ultraviolet light is not affected and passes through and is collected by the Mo / Si multilayer film collector mirror.

[0007] Further, the EUV light source system comprises a vacuum chamber, a laser window and a focusing lens arranged on the vacuum chamber, and a nozzle for delivering a gas target to the laser focal region; the vacuum chamber (1) is maintained at a vacuum degree inside by a vacuum pump.

[0008] Further, the conical chamber is maintained at a vacuum degree inside by an independent molecular pump in the range of 10 -2 Pa to 10 -6 Pa to realize high-voltage insulation and prevent gas discharge; the diameter of the pinhole is less than 5mm and is located at one end of the conical chamber close to the EUV light source system.

[0009] Furthermore, the electrode plate is based on a ceramic semi-cone, and its inner surface facing the plasma source is covered with a conductive layer. Furthermore, the conductive layer is a stainless steel mesh, which is connected to the DC voltage generator via a high-voltage feed flange and wires. The DC voltage generator is configured to provide an adjustable voltage from 0.1 kV to 100 kV to form a 1.5 × 10⁻⁶ kV distribution between the electrode plates. 3 V / m up to 1.5×10 6 Longitudinal electric field of V / m.

[0010] Furthermore, the permanent magnet is composed of multiple permanent magnet material blocks forming a magnetic circuit through a U-shaped magnetic guide plate, and surrounds the outside of the electrode plate to form a transverse magnetic field of 0.1 T to 3 T between the electrode plates.

[0011] Furthermore, it also includes a diagnostic and control system; the diagnostic and control system includes: A Faraday cup is positioned on the opposite side of the Mo / Si multilayer film collecting mirror, with its receiving surface facing the ion escape direction from the electromagnetic field region, for collecting escaped ions and measuring the ion beam intensity. An EUV camera is installed at the rear end of the focusing optical path of the Mo / Si multilayer film collecting mirror to receive the spot image of the IF point. A computer, connected to the Faraday cup and the EUV camera, is used to receive and process monitoring data, and adjust the output voltage of the DC voltage generator and / or control the angular displacement stage driving the Mo / Si multilayer film collecting mirror based on the feedback signals from the Faraday cup and / or the EUV camera.

[0012] Second, the present invention also provides an ion isolation method using the above-mentioned device, characterized in that the method includes the following steps: S1: Generating EUV light and high-energy ions: In a vacuum environment, a pulsed laser is used to excite a gas target to generate plasma, while simultaneously radiating extreme ultraviolet light and generating high-energy ions. S2: Establish a composite electromagnetic field isolation region: Construct a composite electromagnetic field region in which the electric field and magnetic field directions are basically perpendicular along the path of the high-energy ions moving toward the collecting mirror. S3: Deflection and absorption of high-energy ions: The combined electromagnetic field is used to apply electric field force and Lorentz force to positively charged high-energy ions, causing their trajectory to be deflected in combination, thereby deviating from the original optical path and being physically intercepted and absorbed. S4: Non-destructive collection of EUV light: Allows electrically neutral extreme ultraviolet light to pass through the composite electromagnetic field region without damage and be focused and utilized by the Mo / Si multilayer film collection mirror at the rear end; S5: Real-time monitoring and feedback: The ion beam intensity is monitored by a Faraday cup to assess the isolation effect, while the spot quality is monitored by an EUV camera to assess the state of the collection mirror, and the system parameters are adjusted based on the monitoring results.

[0013] Furthermore, in step S5, based on the change in the position of the light spot monitored by the EUV camera, the receiving angle of the Mo / Si multilayer film collecting mirror is adjusted by a computer-controlled angular distribution displacement stage to optimize the collection efficiency of EUV light.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) By combining electric and magnetic fields, a composite electromagnetic field isolation zone is formed. The electric field deflects ions longitudinally, while the magnetic field deflects them laterally. The two work together to produce a deflection effect. The spatial configuration of the electromagnetic field ensures that ions on the straight path from the light source to the collecting mirror are effectively deflected, while maintaining the unobstructed EUV light path. This reduces the number of ions bombarding the Mo / Si multilayer collecting mirror, mitigating mirror damage at its source. The electromagnetic field only affects charged particles and has no adverse effects on the propagation path, intensity, or collection efficiency of EUV light, ensuring the output performance of the light source.

[0015] 2) The use of a conical ceramic cavity as the electrode plate substrate and vacuum isolation component not only achieves reliable insulation under high voltage and prevents short circuits, but its special geometry is also conducive to ion capture and absorption and minimizes the obstruction of EUV light.

[0016] 3) By integrating an EUV camera (to monitor optical performance) and a Faraday cup (to monitor ion flow) with a computer system, real-time, multi-dimensional monitoring and feedback adjustment of ion isolation effect and collecting mirror working status are realized, improving the system's intelligence level and long-term operational stability. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the ion isolation device based on electromagnetic field protection of the EUV collecting mirror according to the present invention.

[0018] Figure 2 (a) is a schematic diagram of the electromagnetic field from the side.

[0019] Figure 2 (b) is a schematic diagram of high-energy ion trajectories.

[0020] Figure 3 This is an optical path diagram inside the vacuum cavity. Detailed Implementation

[0021] To ensure the clarity and completeness of the technical solutions in the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] An ion isolation device based on electromagnetic field protection of an off-axis EUV collecting mirror includes an EUV light source system, a conical chamber, a DC voltage generator, electrode plates, a permanent magnet, a Mo / Si multilayer collecting mirror, an EUV camera, a Faraday cup, and a computer. The EUV light source system includes a vacuum chamber. A laser window is used to transmit laser light into the vacuum chamber, using different lasers, such as Nd:YAG (1064, 532, 266). nm ), Yb:YAG (1030 nm ), Tm fiber DFB (1695-2050) nm ), KrF(248) nm ArF (193) nm ), CO2 (10.6) µm It can emit energy of pulse width The laser is driven by a Faraday rotator to shield the backlight and protect the laser. The laser is focused through a focusing lens onto the center of the cavity to achieve the energy density required for plasma. An excess laser energy is absorbed by a beam collector. The laser irradiates the target material, generating extreme ultraviolet light and producing high-energy ions. The vacuum level of the vacuum cavity needs to be maintained at a constant level. The conical chamber isolates the electrode plates from the vacuum chamber, maintaining [a certain level of vacuum]. The following vacuum levels are used to prevent short circuits, and pinholes prevent laser-excited target material from generating debris that could enter the EUV camera. A DC voltage source can provide 0.1-100... kV The voltage of the electrode plates. - An electric field acts on positively charged high-energy ions, causing the ions to move along the direction of the electric field lines. Permanent magnets can be made of neodymium iron boron, ferrite, samarium cobalt, stainless steel, or molybdenum and can generate 1-3 A strong magnetic field can be generated by arranging individual permanent magnets around the electrode plates, or by using large solid magnets or superconducting magnets. The generated magnetic field acts on positively charged high-energy ions, causing the ions to deflect horizontally perpendicular to the magnetic field lines. Different target materials will produce 0-50... KeVHigh-energy ions are deflected by electric and magnetic fields to prevent them from directly impacting the Mo / Si multilayer film collecting mirror, thus acting as an ion isolator. The EUV camera includes a pinhole camera and a Zr filter. The Zr filter only allows 5-20... nm Light of a specific wavelength can pass through, effectively shielding visible light and scattered laser light. The pinhole is located at the front IF point of the EUV camera receiver, allowing control over the plasma spot size to ensure the image is fully projected onto the EUV camera. A Mo / Si multilayer film collecting mirror achieves a center wavelength with a bandwidth of 13.5 nm. The EUV radiation is collected and focused at the IF point to improve the collection efficiency of the EUV light. A Faraday cup is used to collect the signal generated by ions and measure the beam intensity of ion debris.

[0023] Furthermore, the computer is used to record, analyze, and calculate images and signals from the EUV camera, CCD camera, Faraday cup, and EUV energy meter; and to adjust electronic controls such as the displacement stage.

[0024] This embodiment provides an ion isolation device based on electromagnetic field protection for off-axis Xe-LPP extreme ultraviolet light collecting mirrors. It is intended to protect off-axis collecting mirrors, but the protective effect on ions incident on the collecting mirrors is relatively small. This example uses xenon gas as the target material to generate extreme ultraviolet light sources, mainly to isolate high-energy xenon ions and extend the service life of the collecting mirrors.

[0025] See Figure 1 The schematic diagram of the ion isolation device based on electromagnetic field protection of EUV collecting mirror in this embodiment of the invention includes the following core components: Vacuum chamber 1: pumped to vacuum level by vacuum pump 23 The vacuum level is then observed by vacuum gauge 22. Laser window 12 transmits the laser source generated by laser 10 via Faraday rotator 11 into the vacuum cavity, where it is focused by focusing lens 13 onto nozzle 14, achieving a high vacuum level at the laser intersection point. The gas atomic density. Using an Nd:YAG laser, the emission wavelength is 1064 nm, and the pulse width is less than 10. ns Energy 450-700 mJ Adjustable drive laser. Gas feed flange 18 introduces target gas from gas cylinder 19 into vacuum chamber 1, with adjustable gas pressure. The laser energy is ejected through a Teflon hose 17 and finally exited through a nozzle 14. A beam collector 16 absorbs excess laser energy. The nozzle 14, made of stainless steel, allows the introduction of a gas target and focuses the gas towards the laser focal point. A three-axis displacement stage 15 (step 10) is included. nm It is precisely positioned 1 mm directly below the laser focus.

[0026] Vacuum Chamber 1: See Figure 3The system includes an EUV energy meter 21, which measures the intensity of EUV radiation at the nozzle; arranged sequentially along the optical path: a Zr filter 40 with a thickness of 200 nm, allowing only light with wavelengths of 5-20 nm to pass through, used to filter out visible light and scattered laser light; two Mo / Si multilayer film mirrors 41, used to further purify the spectrum, allowing only EUV radiation within the band of 13.5 ± 1% nm to pass through; and a photodiode 42, used to receive EUV radiation within the band and convert it into an electrical signal. An EUV camera 20 measures the image and position of the plasma at the nozzle, and includes a pinhole 38, a Zr filter 39, and a CCD camera 43. The pinhole 38 is located at the center of the receiving surface of the CCD camera 43 and the laser focal point, obtaining an image of the plasma source of the same size through the principle of pinhole imaging. The Zr filter 39 has the same performance and function as the Zr filter 40.

[0027] Conical chamber 2: Isolation electrode plate 4 and vacuum chamber 1, with a thickness of 10. mm The vacuum level of the electrode plate is maintained at a certain level by using molecular pump 29. The vacuum gauge 28 detects the vacuum level inside the conical cavity to prevent short circuits caused by high voltage, thus preventing positively charged xenon ions from converting to neutral charges and damaging the collecting mirror; the diameter of the pinhole 27 is less than 5 mm. mm This ensures that the extreme ultraviolet light source can be incident on the Mo / Si multilayer film collecting mirror 6.

[0028] DC voltage generator 3: The voltage source applies a voltage of 1kV or higher, and through the high-voltage feed flange 24, the copper wire 26 supplies power to the electrode plate 4 to generate an electric field.

[0029] Electrode plate 4: See Figure 2 (a) Two ceramic semi-cones 4-2 are installed in parallel, with a thickness of 5. mm The total length of the cone is 70. mm The bottom diameter is 50 mm The top diameter is 20 mm It is divided into upper and lower parts. The two semi-conical parts do not contact each other, so they will not cause a short circuit. The DC voltage generator 3 uses copper wire 26 to connect the upper stainless steel mesh 4-1 of the electrode plate 4, and ground wire 25 to connect the lower stainless steel mesh 4-1 of the electrode plate 4. A voltage is generated between the stainless steel meshes 4-1. The electric field causes xenon ions to travel along the electric field lines through the stainless steel mesh 4-1 and into the interior of the cone.

[0030] Permanent magnet 5: See Figure 2 (a) The permanent magnet 5 is made of 10 pieces of neodymium iron boron 5-2, each with a length of 30 mm. mm, 35 mm 40 mm 45 mm 50 mm Width 10mm Thickness 5 mm A stainless steel U-shaped plate 5-1 is connected to two neodymium iron boron electrodes 5-2 at the top and bottom, forming a stable magnetic circuit to protect the device. A vertically downward parallel magnetic field is generated between the electrode plates, with each group providing a magnetic field of 0.353T, causing xenon ions to move horizontally in a direction perpendicular to the magnetic field lines. (See also...) Figure 2 (b) Schematic diagram of high-energy ion trajectory; the ion trajectory changes under the combined action of electric and magnetic fields. The dashed line represents the movement of ions inside electrode plate 4, and the solid line represents the trajectory of EUV light propagation. The light passes through pinhole 27 and is not blocked by electrode plate 4. At the same time, it ensures that high-energy ions do not directly hit Mo / Si multilayer film collecting mirror 6, but are directly absorbed by cone 4-2, which plays a role in isolating ions.

[0031] Mo / Si multilayer film collecting mirror 6: The optical path of this structure is described in [reference]. Figure 3 This includes pinhole 31, Zr filter 30, and EUV camera. Above nozzle 13 1 mm The plasma generated is filtered by a Zr filter 30, ensuring that only light with wavelengths of 5-20 nm passes through, effectively shielding visible light and scattered laser light. The EUV light image radiated by the plasma is focused at the IF point by a Mo / Si multilayer film collecting mirror 6. The pinhole 31 is located at the IF point at the front of the receiving face of the EUV camera 5, allowing the radiated EUV light image to be clearly presented within the receiving plane of the EUV camera 5.

[0032] EUV camera 7: A gate valve 30 isolates the conical cavity 2 and the EUV imaging 7; a Mo / Si multilayer film collecting mirror 6, controllable by an angular displacement stage 33, allows for fine-tuning of the collecting mirror's receiving angle and achieves a center wavelength of 13.5 nm. nm bandwidth EUV radiation is concentrated at the IF point by the collecting mirror, improving the collection and utilization efficiency of the light source. The EUV camera 7 receives the plasma spot focused at the IF point by the collecting mirror; recording and analyzing changes in the plasma spot can indicate whether the collecting mirror has been damaged. The molecular pump 32 maintains the intracavitary pressure at... Next, vacuum gauge 31 detects the internal pressure; when the air pressure in the three chambers tends to be consistent, the slide valve 30 is opened.

[0033] Faraday Cup 8: The receiving plane is made of aluminum, with a 100-mesh metal grid placed at the front end of the receiving face, effectively reducing the influence of secondary electrons generated on the high-energy ion signal. It can measure the beam intensity of ion debris.

[0034] Computer 8: Data line 35 receives the spot image from EUV camera 7 and analyzes the spot size and position at the IF point; data line 35 receives the spot image from CCD camera 20 and analyzes the spot size and position at the nozzle; BNC line 44 receives the signal generated by Faraday cup 8 and calculates the beam intensity of all high-energy ions generated by Xe-LPP extreme ultraviolet light source; BNC line 44 receives EUV energy meter 21 and records the extreme ultraviolet light energy at the nozzle; data line 34 connects to angular distribution displacement stage 33 and controls the receiving angle of the collecting mirror to generate different plasma images in the EUV camera.

[0035] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention. Where there is no conflict, the above embodiments and features described therein can be combined with each other.

Claims

1. An ion isolation device for protecting an off-axis EUV collection mirror based on an electromagnetic field, characterized by In order from the direction of the light path transmission, comprising: An EUV light source system for generating extreme ultraviolet light and accompanying high-energy ions; A conical chamber (2) having an entrance end in optical communication with a vacuum cavity of the EUV light source system through a pinhole (27); An electromagnetic deflection assembly arranged inside the conical chamber (2) for forming a composite electromagnetic field, the electromagnetic deflection assembly being composed of parallel and opposite electrode plates (4) and a permanent magnet (5) for generating a transverse magnetic field, and the magnetic field generated by the permanent magnet (5) is perpendicular to the electric field generated between the electrode plates (4), thereby forming an electromagnetic field region for deflecting the high-energy ions; A Mo / Si multilayer film collector mirror (6) arranged at the exit end of the conical chamber (2) for receiving and focusing the extreme ultraviolet light passing through the electromagnetic deflection region; Wherein, the electrode plates (4) are electrically connected to a direct current voltage generator (3) to generate an electric field, and when the high-energy ions pass through the electromagnetic field region, the movement trajectory is deflected and absorbed by the inner wall of the conical chamber (2) or the electrode plates (4), while the extreme ultraviolet light is not affected and is collected by the Mo / Si multilayer film collector mirror (6).

2. An ion shield for protecting an off-axis EUV collection mirror based on an electromagnetic field according to claim 1, characterized in that The EUV light source system comprises a vacuum cavity (1), a laser window (12) and a focusing lens (13) arranged on the vacuum cavity (1), and a nozzle (14) for delivering a gas target to a laser focal region; the vacuum cavity (1) maintains a vacuum degree inside by a vacuum pump (23).

3. The electromagnetic field based ion shield for off-axis EUV collection mirrors of claim 1, wherein, The conical chamber (2) maintains its internal vacuum degree at 10 -2 Pa to 10 -6 Pa range to achieve high voltage insulation and prevent gas discharge; the pinhole (27) has a diameter less than 5 mm and is located at one end of the conical chamber (2) close to the EUV light source system.

4. The electromagnetic field based ion shield for off-axis EUV collection mirrors of claim 1, wherein, The base of the electrode plate (4) is a ceramic half-cone (4-2), and the inner surface facing the plasma source is covered with a conductive layer (4-1).

5. An ion isolation device for protecting an off-axis EUV collection mirror based on an electromagnetic field according to claim 4, characterized in that The electrically conductive layer (4-1) is a stainless steel mesh connected with the DC voltage generator (3) via a high-voltage feedthrough flange (24) and a wire (26), the DC voltage generator (3) being configured to provide an adjustable voltage of 0.1 kV to 100 kV to form a longitudinal electric field of 1.5 x 10 3 V / m to 1.5 x 10 6 V / m between the electrode plates (4).

6. The ion isolation apparatus for protecting an off-axis EUV collection mirror based on an electromagnetic field according to claim 4, characterized in that, The permanent magnet (5) is composed of multiple permanent magnet blocks (5-2) through a U-shaped magnetic conducting plate (5-1) to form a magnetic circuit, and is wrapped around the outside of the electrode plate (4) to form a transverse magnetic field of 0.1 T to 3 T between the electrode plates (4).

7. An ion shield for protecting an off-axis EUV collector mirror based on an electromagnetic field according to any of claims 1 to 6, characterized in that It also includes a diagnosis and control system; the diagnosis and control system comprises: A Faraday cup (8) arranged on the opposite side of the Mo / Si multilayer film collector mirror (6), with its receiving surface facing the ion escape direction from the electromagnetic field region, for collecting escaped ions and measuring ion beam current intensity; An EUV camera (7) arranged at the rear end of the focusing light path of the Mo / Si multilayer film collector mirror (6) for receiving the spot image of the IF point; A computer (9) connected to the Faraday cup (8) and the EUV camera (7) for receiving and processing monitoring data, and adjusting the output voltage of the direct current voltage generator (3) and / or controlling the angular distribution displacement table (33) driving the Mo / Si multilayer film collector mirror (6) according to the feedback signal of the Faraday cup (8) and / or the EUV camera (7).

8. A method for ion isolation using the apparatus according to any one of claims 1 to 6, characterized by, The method comprises the following steps: S1: generating EUV light and high-energy ions: in a vacuum environment, a gas target is excited by a pulsed laser to generate a plasma, and at the same time, extreme ultraviolet light is radiated and high-energy ions are generated; S2: Establishing a composite electromagnetic field isolation zone: A composite electromagnetic field region with the electric field and magnetic field directions being substantially perpendicular is constructed on the path of the high-energy ions moving towards the collection mirror; S3: Deflecting and absorbing high-energy ions: The composite electromagnetic field is used to exert electric field force and Lorentz force on the positively charged high-energy ions, so that the motion trajectory of the high-energy ions is deflected and deviated from the original light path and is physically intercepted and absorbed; S4: Non-destructive collection of EUV light: The electrically neutral extreme ultraviolet light passes through the composite electromagnetic field region without being damaged and is focused by the Mo / Si multilayer film collection mirror (6) at the rear end for utilization; S5: Real-time monitoring and feedback: The ion beam intensity is monitored by the Faraday cup (8) to evaluate the isolation effect, and the light spot quality is monitored by the EUV camera (7) to evaluate the state of the collection mirror, and the system parameters are adjusted according to the monitoring results.

9. The ion isolation method according to claim 8, wherein, In step S5, according to the change of the light spot position monitored by the EUV camera (7), the receiving angle of the Mo / Si multilayer film collection mirror (6) is adjusted by the computer (9) to control the angular distribution displacement table (33) to optimize the collection efficiency of the EUV light.

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