Device for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position

Abstract

The present invention relates to a device for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position. The first ionization chamber and the second ionization chamber in the present invention are both composed of a vacuum chamber and a vacuum pump, and the vacuum chamber is independently evacuated by the vacuum pump; the first ionization chamber and the second ionization chamber are both installed with a vacuum gauge and a needle valve; the first ionization chamber is also equipped with a resistance thermometer for detecting the ambient temperature in the first ionization chamber. The charged particle detector in the present invention includes an ion confinement electrode plate, an accelerating electrode plate, a splitting electrode plate, an ammeter, a microchannel electron multiplier tube and an oscilloscope. The present invention realizes simultaneous online nondestructive detection of the pulse energy of the laser to be measured and its spatial position information, simplifies the detection operation process, takes into account the detection and use of the laser, greatly improves the light efficiency of the user at the back end of the detection device, and the detection parameters of the laser to be measured obtained are more timely and accurate.

Description

Technical Field

[0001] The invention belongs to the technical field of optical nondestructive testing, and relates to a device for online nondestructive testing of extreme ultraviolet laser pulse energy and light beam spatial position. Background Art

[0002] Since its invention in the 1960s, lasers have been widely used in industrial manufacturing, medical care, aerospace, national defense and military, cutting-edge scientific research and other fields, and have greatly promoted the innovative development of cutting-edge interdisciplinary research and high-tech fields. With the continuous development and breakthroughs in laser technology, the laser output by the new generation of light sources, free electron lasers, has already covered the extreme ultraviolet band (EUV, 10-121nm). As we all know, lasers with wavelengths below 200nm are easily strongly absorbed by oxygen in the air. Therefore, the extreme ultraviolet laser output by the free electron laser must be introduced through a beam line (in a high vacuum or ultra-high vacuum environment) for user use. Due to this particularity, users cannot obtain the pulse energy and spatial position of the extreme ultraviolet laser during the use of light, which are important parameter information that characterizes laser performance.

[0003] At present, commercial devices used for laser pulse energy detection are mainly divided into semiconductor photodiode detectors and thermocouple detectors. The detection method of this type of detector is interception detection, and it is easy to be saturated, degraded or even damaged under short-wavelength laser irradiation. In response to this defect, short-wavelength laser pulse energy detection devices based on the working principle of rare gas photoionization have emerged, among which the most typical ones are photoionization photometers and double ionization chambers. The former is mainly composed of a photoionization chamber and a time-of-flight mass spectrometer. The ions generated by photoionization in the interaction area between the laser to be measured and the rare gas are detected by the microchannel plate in the time-of-flight mass spectrometer, and then the laser energy is calibrated according to basic atomic constants such as the photoionization cross section and the electron-atom ionization cross section. Although this technology can realize online non-destructive detection of extreme ultraviolet laser pulse energy, it requires the use of an electron beam with known intensity and energy to calibrate the photometer in advance through electron-atom ionization. In addition, the microchannel plate may be saturated or even damaged when measuring ions generated by high-intensity photon flux. These factors will lead to the complexity and uncertainty of the photoionization photometer when detecting the energy of extreme ultraviolet laser pulses. The working pressure of another detection device, the double ionization chamber, is as high as about 0.1mbar, which will cause a certain loss of the energy of the extreme ultraviolet laser pulse to be tested, making it impossible to achieve online non-destructive testing. In addition, due to the high density of the gas in the ionization chamber, the ions after photoionization are very likely to undergo secondary ionization, making the situation particularly complicated.

[0004] In terms of detecting the spatial position information of laser beams, one of the important measurement methods is to use a position-sensitive microchannel plate to collect charged particles generated by laser photoionization. The particles bombard the microchannel plate to generate gain-amplified electrons and are captured by the phosphor screen at the back end, thereby extracting an image that retains the initial charged particle position information. Finally, a camera is used to capture the image on the phosphor screen to indirectly obtain the spatial position information of the laser beam. This method has certain limitations on the energy of the laser to be measured because it needs to avoid damage to the microchannel plate caused by high-intensity charged particles, and signal oversaturation can easily cause distortion of the image collected by the phosphor screen. In addition, another measurement method is the knife-edge scanning method, which directly uses the knife edge to periodically cut the beam and uses the photoelectric detection system to receive the transmitted light to obtain the lateral position information of the beam. Although this method is more practical for high-energy lasers, it requires mechanical operation, so the human error is large. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a device for online non-destructive detection of extreme ultraviolet laser pulse energy and beam spatial position.

[0006] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0007] The present invention comprises a first ionization chamber, a second ionization chamber, a charged particle detector and a differential extraction system.

[0008] The first ionization chamber and the second ionization chamber are both composed of a vacuum chamber and a vacuum pump. The vacuum chamber is independently evacuated by the vacuum pump to provide a high vacuum environment for detecting the energy of the extreme ultraviolet laser pulse and the spatial position of the beam. The first ionization chamber and the second ionization chamber are both equipped with a vacuum gauge and a needle valve, wherein the vacuum gauge is used to measure the vacuum degree in the ionization chamber filled with a rarefied rare gas in real time, and the needle valve is used to control the flow of the rare gas filled into the ionization chamber, and cooperates with the vacuum pump to maintain a constant pressure in the ionization chamber. The first ionization chamber is also equipped with a resistance thermometer for detecting the ambient temperature in the first ionization chamber.

[0009] The charged particle detector comprises an ion confinement electrode plate, an accelerating electrode plate, a splitting electrode plate, an ammeter, a micro-channel electron multiplier tube and an oscilloscope.

[0010] The accelerating electrode plates consist of two electrode plates with holes in the center and covered with grids. An electric field is formed by applying positive and negative voltages to the electrode plates respectively. The electrons and ions generated by photoionization in the transmission direction of the extreme ultraviolet laser are accelerated and projected to the splitting electrode plates under the action of the electric field.

[0011] The ion confinement electrode plate is assembled from multiple circular electrode plates, and its main function is to pull ions that are at the edge of the accelerating electrode plate or that may escape from the accelerating electrode plate back to the effective detection area of ​​the splitting electrode plate, thereby improving detection accuracy.

[0012] The split electrode plate is composed of two electrode plates spliced ​​together, which are insulated from each other. A small rectangular hole covering the grid is left in the center of the split electrode plate at the ion signal detection end, which is convenient for a very small number of ions to pass through the grid and enter the microchannel electron multiplier tube. The ammeter connected to the split electrode plate at the ion signal detection end measures the average current formed by the ions accumulated on the two electrode plates within a certain period of time; the rear end of the split electrode plate at the ion signal detection end is connected to the microchannel electron multiplier tube and the oscilloscope, while the rear end of the split electrode plate at the electronic signal detection end is directly connected to the oscilloscope, which are used to measure the ion signal or electronic signal of a single pulse respectively.

[0013] Among them, the microchannel electron multiplier tube at the ion signal detection end is used to amplify the part of the ion signal that passes through the grid, and then the average charge of the ion can be deduced from the pulsed ion flight time spectrum measured by the oscilloscope.

[0014] The pulse electronic signal measured by the oscilloscope at the electronic signal detection end is only used as a relative value. The pulse electronic signal within a specific time is integrated and calibrated with the average current signal measured by the ammeter.

[0015] In the first ionization chamber, the accelerating electrode plate and the splitting electrode plate of the charged particle detector are arranged in sequence in the y-axis direction, which are mainly used for online nondestructive detection of the pulse energy of the extreme ultraviolet laser and the offset position and offset distance of the light beam in the x-axis direction. In the second ionization chamber, the accelerating electrode plate and the splitting electrode plate of the charged particle detector are arranged in sequence in the x-axis direction, which are used for online nondestructive detection of the offset position and offset distance of the extreme ultraviolet laser in the y-axis direction.

[0016] The differential pumping system is composed of a multi-stage chamber and a vacuum pump, which are respectively installed at the front end of the first ionization chamber, the rear end of the second ionization chamber, and between the first ionization chamber and the second ionization chamber, so that the rare gas in the vacuum chamber is completely bound within the entire detection device, and the first ionization chamber and the second ionization chamber do not interfere with each other, ensuring that the preparation and transmission of the extreme ultraviolet laser at the front end of the detection device and the use of the laser at the rear end of the detection device are not affected during online detection.

[0017] Preferably, the vacuum pump is a magnetic levitation molecular pump, which is sealed and connected to the vacuum chamber or the multi-stage chamber via a knife-edge flange.

[0018] Preferably, the ammeter is a picoammeter, which has the advantage of lower noise when measuring current compared to a general ammeter.

[0019] The first ionization chamber, the second ionization chamber and each differential extraction system are connected by a retractable welded bellows with knife-edge flanges welded at both ends for non-rigid sealing, thereby ensuring the airtightness and adjustability of the entire detection device. By adjusting the installation positions of the first ionization chamber and the second ionization chamber and the relative positions of the split electrode plates during installation, the center line of the split electrode plates is adjusted to the z-axis of the reference coordinate system, thereby ensuring the accuracy of the measured values ​​of the spatial position of the light beam.

[0020] When adjusting the needle valve, the intake amount of the rare gas needs to be strictly controlled so that the vacuum degree in the first ionization chamber and the second ionization chamber does not differ in magnitude before and after the intake of the gas. Without affecting the use of the extreme ultraviolet laser at the rear end of the detection device, non-destructive detection of the laser pulse energy and the spatial position of the beam can be completed.

[0021] The method for online nondestructive detection of extreme ultraviolet laser pulse energy and light beam spatial position using the above device is as follows: the laser to be tested is introduced into an ionization chamber in which rarefied rare gas is evenly distributed, and along the transmission direction of the laser to be tested, ions and electrons generated by photoionization of the rare gas are rapidly projected to a split electrode plate under the action of an electric field, and an ammeter connected to the split electrode plate measures the current generated by the accumulation of ions or electrons, wherein the number of photons contained in each pulse of the extreme ultraviolet laser can be deduced based on the sum of the current values ​​of each part of the split electrode plate detected, and then the pulse energy of the extreme ultraviolet laser can be calculated; at the same time, the ratio of the current values ​​measured in each part of the split electrode plate can be inversely deduced The specific offset direction and offset distance of the extreme ultraviolet laser in a plane perpendicular to the laser transmission direction, and the spatial position information of the light beam is indirectly obtained.

[0022] The present invention has the following advantages and beneficial effects:

[0023] The present invention detects the value of the current formed on the splitting electrode plate by ions and electrons generated by the photoionization of rare gas by extreme ultraviolet laser to infer the laser pulse energy and the spatial position information of the light beam, which not only takes into account the simultaneous detection of two important parameters of the laser to be measured, simplifies the detection operation process, but also greatly improves the service life of the detection device because there is no damage to any detection element; in addition, the rare gas used in the ionization chamber is extremely thin, which will neither intercept the laser to be measured nor affect the initial energy and spatial position of the laser to be measured, thereby achieving the purpose of online non-destructive detection of extreme ultraviolet laser, which takes into account the detection and use of the laser, greatly improves the light efficiency of the user at the back end of the detection device, and the detection parameters of the laser to be measured obtained are more timely and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the device structure of the present invention, Figure 2 Schematic diagram of the split electrode plate.

[0025] Among them, 1. vacuum chamber, 2. vacuum pump, 3. vacuum gauge, 4. needle valve, 5. resistance thermometer, 6. ion confinement electrode plate, 7. acceleration electrode plate, 8. splitting electrode plate, 9. ammeter, 10. microchannel electron multiplier tube, 11. oscilloscope, 12. multi-stage chamber. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0027] like Figure 1 As shown, this embodiment includes a first ionization chamber, a second ionization chamber, a charged particle detector and a differential extraction system.

[0028] The first ionization chamber and the second ionization chamber are both composed of a vacuum chamber 1 and a vacuum pump 2. The vacuum chamber 1 is independently evacuated by the vacuum pump 2 to provide a high vacuum environment for detecting the energy of the extreme ultraviolet laser pulse and the spatial position of the beam. The first ionization chamber and the second ionization chamber are both installed with a vacuum gauge 3 and a needle valve 4, wherein the vacuum gauge 3 is used to measure the vacuum degree in the ionization chamber filled with a rarefied rare gas in real time, and the needle valve 4 is used to control the flow of the rare gas filled into the ionization chamber, and cooperates with the vacuum pump 2 to maintain a constant pressure in the ionization chamber. The first ionization chamber is also equipped with a resistance thermometer 5 for detecting the ambient temperature in the first ionization chamber.

[0029] The charged particle detector mainly includes an ion confinement electrode plate 6, an accelerating electrode plate 7, a splitting electrode plate 8, an ammeter 9, a microchannel electron multiplier tube 10 and an oscilloscope 11. The accelerating electrode plate 7 is composed of two electrode plates with holes opened at the center and covered with a grid. An electric field is formed by applying positive and negative voltages on the electrode plates respectively. The electrons and ions generated by photoionization in the transmission direction of the extreme ultraviolet laser are accelerated and projected to the splitting electrode plate 8 under the action of the electric field; the ion confinement electrode plate 6 is assembled from a plurality of circular ring-shaped electrode plates, and is mainly used to pull ions at the edge of the accelerating electrode plate 7 or that may escape from the accelerating electrode plate 7 back to the effective detection area of ​​the splitting electrode plate 8, thereby improving the detection accuracy. The split electrode plate 8 is composed of two electrode plates spliced ​​together, which are insulated from each other. A rectangular small hole covering the grid is left at the center of the split electrode plate 8 at the ion signal detection end, which is convenient for a very small amount of ions to pass through the grid and enter the microchannel electron multiplier tube 10. The ammeter 9 connected to the split electrode plate 8 at the ion signal detection end measures the average current formed by the ions accumulated on the two electrode plates within a certain period of time; the rear end of the split electrode plate 8 at the ion signal detection end is connected to the microchannel electron multiplier tube 10 and the oscilloscope 11, and the rear end of the split electrode plate 8 at the electronic signal detection end is directly connected to the oscilloscope 11, which are used to measure the ion signal or electronic signal of a single pulse, respectively. The microchannel electron multiplier tube 10 at the ion signal detection end is used to amplify the part of the ion signal that passes through the grid. The average charge of the ions can be deduced from the pulse ion flight time spectrum measured by the oscilloscope 11. The pulse electronic signal measured by the oscilloscope 11 at the electronic signal detection end is only used as a relative value. The pulse electronic signal within a specific time is integrated and calibrated with the average current signal measured by the ammeter 9. In the first ionization chamber, the accelerating electrode plate 7 and the splitting electrode plate 8 of the charged particle detector are arranged in sequence in the y-axis direction, which are mainly used for online non-destructive detection of the pulse energy of the extreme ultraviolet laser and the offset position and offset distance of the light beam in the x-axis direction. In the second ionization chamber, the accelerating electrode plate 7 and the splitting electrode plate 8 of the charged particle detector are arranged in sequence in the x-axis direction, which are used for online non-destructive detection of the offset position and offset distance of the extreme ultraviolet laser in the y-axis direction.

[0030] The differential pumping system is composed of a multi-stage chamber 12 and a vacuum pump 2, which are respectively installed at the front end of the first ionization chamber, the rear end of the second ionization chamber, and between the first ionization chamber and the second ionization chamber, so that the rare gas in the vacuum chamber is completely bound within the entire detection device, and the first ionization chamber and the second ionization chamber do not interfere with each other, ensuring that the preparation and transmission of the extreme ultraviolet laser at the front end of the detection device and the use of the laser at the rear end of the detection device are not affected during online detection.

[0031] The method for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position using the above device is as follows:

[0032] The laser to be measured is introduced into an ionization chamber in which a rarefied gas is evenly distributed. Along the transmission direction of the laser to be measured, ions and electrons generated by photoionization of the rare gas are rapidly projected to a splitting electrode plate under the action of an electric field. An ammeter connected to the splitting electrode plate measures the current generated by the accumulation of ions or electrons. The number of photons contained in each pulse of the extreme ultraviolet laser can be deduced based on the sum of the current values ​​of each part of the splitting electrode plate detected, and then the pulse energy of the extreme ultraviolet laser can be calculated. At the same time, the ratio of the current values ​​measured in each part of the splitting electrode plate can be used to infer the specific offset direction and offset distance of the extreme ultraviolet laser in a plane perpendicular to the laser transmission direction, thereby indirectly obtaining the spatial position information of the light beam.

[0033] The specific implementation process of the present invention is as follows:

[0034] 1. According to Figure 1 Assemble the components of the device, especially place the center line of the split electrode plate on the z-axis of the reference coordinate system;

[0035] 2. Connect the entire detection device between the beam line of the free electron laser and the user device;

[0036] 3. Turn on the vacuum pump and evacuate the vacuum chamber and multi-stage chamber to 10 -8 torr level;

[0037] 4. Adjust the needle valve to slowly fill the rare gas - xenon into the first ionization chamber and the second ionization chamber to ensure that the gas concentration in the vacuum chamber is thin and the gas pressure is constant;

[0038] 5. The extreme ultraviolet laser output by the free electron laser is introduced into the detection device, and the rare gas in the vacuum chamber, xenon, is ionized by photoionization to generate ions and electrons;

[0039] 6. The accelerating electrode plate in the ionization chamber projects the ions and electrons in the direction of laser transmission to the splitting electrode plate respectively;

[0040] 7. If Figure 2 As shown, the current I is measured by the ammeters connected to the split electrode plates a and b at the ion signal detection end in the first ionization chamber. xa and I xb The part of ions that pass through the grid on the split electrode plate is amplified by the micro-channel electron multiplier tube and then sampled by the oscilloscope to obtain the pulse ion flight time spectrum. The resistance thermometer measures the gas temperature in the first ionization chamber as T, and the vacuum gauge measures the pressure in the first ionization chamber as p. The ammeters connected to the split electrode plates a and b at the ion signal detection end in the first ionization chamber measure the current I respectively. ya and I yb ,

[0041] The number of ions N detected by the split electrode plate in time t ions for:

[0042] N ions =Q / eγ=(I xa +I xb )t / eγ

[0043] Among them, Q is the accumulated charge on the splitting electrode plate within time t, e is the elementary charge, and γ is the average charge of ions produced by the photoionization of the noble gas, which can be obtained by analyzing the pulsed ion flight time spectrum acquired by the oscilloscope.

[0044] In the laser photoionization process, the number of photons N photon and the number of ions N ions The Beer-Lambert law is followed:

[0045]

[0046] Among them, σ ph is the photoionization cross section of the noble gas at the wavelength of the laser to be measured; Z eff is the effective length of the split electrode plate along the laser transmission direction; n atom =p / kT is the number density of the noble gas in the vacuum chamber and is the Boltzmann constant;

[0047] Thus, the number of photons per pulse n photon for:

[0048] n photon =N photon / tv=N ions kT / (σ ph Z eff ptv)=(I xa +I xb )kT / (σ ph Z eff pvγe)

[0049] Where v is the laser operating frequency.

[0050] Therefore, the pulse energy E of the laser to be measured is:

[0051] E=hcn photon / λ=(I xa +I xb )kThc / (σ ph Z eff pvγeλ)

[0052] Among them, h is Planck's constant, c is the speed of light in a vacuum, and λ is the wavelength of the laser to be measured.

[0053] like Figure 2 As shown, the offset Δx of the laser to be measured in the x-axis direction, and the ratio of the current values ​​measured on the separation electrode plates a and b in the first ionization chamber are:

[0054] I xa / I xb =(Z a +Z a ') / (Z b +Z b ')=(d+2Δx) / (d-2Δx)

[0055] Where d is the effective width of the split electrode plate.

[0056] Therefore, the deviation Δx of the laser beam to be measured on the x-axis can be obtained as follows:

[0057] Δx=d(I xa -I xb ) / 2[I xa +I xb ]

[0058] When Δx>0, it indicates that the laser beam to be measured deviates by a distance |Δx| along the positive axis in the x-axis direction. When Δx<0, it indicates that the laser beam to be measured deviates by a distance |Δx| along the negative axis in the x-axis direction.

[0059] Similarly, the deviation Δy of the laser beam to be measured on the y-axis is:

[0060] Δy=d(I ya -I yb ) / 2[I ya +I yb ]

[0061] When Δy>0, it indicates that the laser beam to be measured deviates by a distance |Δy| along the positive axis in the y-axis direction. When Δy<0, it indicates that the laser beam to be measured deviates by a distance |Δy| along the negative axis in the y-axis direction.

Claims

1. A device for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position, characterized in that: It includes a first ionization chamber, a second ionization chamber, a charged particle detector and a differential extraction system; The first ionization chamber and the second ionization chamber are both composed of a vacuum chamber (1) and a vacuum pump (2); the vacuum chamber (1) is independently evacuated by the vacuum pump (2) to provide a high vacuum environment for detecting the energy of extreme ultraviolet laser pulses and the spatial position of the light beam; The first ionization chamber and the second ionization chamber are both equipped with a vacuum gauge (3) and a needle valve (4), wherein the vacuum gauge (3) is used to measure the vacuum degree in the ionization chamber filled with rarefied rare gas in real time, and the needle valve (4) is used to control the flow rate of the rare gas filled into the ionization chamber, and cooperates with the vacuum pump (2) to maintain a constant pressure in the ionization chamber; the first ionization chamber is also equipped with a resistance thermometer (5) for detecting the ambient temperature in the first ionization chamber; The charged particle detector comprises an ion confinement electrode plate (6), an accelerating electrode plate (7), a splitting electrode plate (8), an ammeter (9), a micro-channel electron multiplier tube (10) and an oscilloscope (11); The accelerating electrode plate (7) is composed of two electrode plates with holes opened at the center and covered with a grid. An electric field is formed by applying positive and negative voltages to the electrode plates respectively. Electrons and ions generated by photoionization in the transmission direction of the extreme ultraviolet laser are accelerated and projected to the splitting electrode plate (8) under the action of the electric field. The ion confinement electrode plate (6) is assembled from a plurality of annular electrode plates and is used to pull ions that are at the edge of the accelerating electrode plate (7) or that may escape from the accelerating electrode plate (7) back to the effective detection area of ​​the splitting electrode plate (8); The split electrode plate (8) is formed by splicing two electrode plates, which are insulated from each other. A rectangular small hole covering a grid is left at the center of the split electrode plate (8) at the ion signal detection end, so that a very small amount of ions can pass through the grid and enter the micro-channel electron multiplier tube (10). The ammeter (9) connected to the split electrode plate (8) at the ion signal detection end respectively measures the average current formed by the ions accumulated on the two electrode plates within a certain period of time. The rear end of the split electrode plate (8) at the ion signal detection end is connected to the micro-channel electron multiplier tube (10) and the oscilloscope (11), and the rear end of the split electrode plate (8) at the electronic signal detection end is directly connected to the oscilloscope (11), which are used to measure the ion signal or electronic signal of a single pulse, respectively. The microchannel electron multiplier tube (10) is used to amplify the ion signal that passes through the grid, and then the pulse ion flight time spectrum is measured by an oscilloscope (11) connected to the microchannel electron multiplier tube (10), thereby obtaining the average charge of the ions; The pulse electronic signal measured by the oscilloscope (11) at the electronic signal detection end is used only as a relative value, and the pulse electronic signal within a set time is integrated and calibrated with the average current signal measured by the ammeter (9); In the first ionization chamber, the accelerating electrode plate (7) and the splitting electrode plate (8) of the charged particle detector are arranged in sequence in the y-axis direction, and are used for online non-destructive detection of the pulse energy of the extreme ultraviolet laser and the offset position and offset distance of the light beam in the x-axis direction; in the second ionization chamber, the accelerating electrode plate (7) and the splitting electrode plate (8) of the charged particle detector are arranged in sequence in the x-axis direction, and are used for online non-destructive detection of the offset position and offset distance of the extreme ultraviolet laser in the y-axis direction; the x-axis and the y-axis are two axes in a reference coordinate system, and the other axis in the reference coordinate system, i.e., the z-axis, passes through the center line of the splitting electrode plate (8); The differential extraction system is composed of a multi-stage chamber (12) and a vacuum pump (2), which are respectively installed at the front end of the first ionization chamber, the rear end of the second ionization chamber, and between the first ionization chamber and the second ionization chamber, so that the rare gas in the vacuum chamber is completely bound within the entire detection device, and the first ionization chamber and the second ionization chamber do not interfere with each other, ensuring that the preparation and transmission of the extreme ultraviolet laser at the front end of the detection device and the use of the laser at the rear end are not affected during online detection.

2. The device for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position according to claim 1, characterized in that: The vacuum pumps (2) are all magnetic levitation molecular pumps, and are sealedly connected to the vacuum chamber (1) and the multi-stage chamber (12) through knife-edge flanges.

3. The device for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position according to claim 1, characterized in that: The ammeter (9) is a picoammeter.

4. The device for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position according to claim 1, characterized in that: The first ionization chamber, the second ionization chamber and each differential extraction system are connected in a non-rigid sealed manner via a retractable welded bellows with welded knife-edge flanges at both ends, thereby ensuring the airtightness and adjustability of the entire detection device. By adjusting the installation positions of the first ionization chamber and the second ionization chamber and their relative positions to the split electrode plate (8), the center line of the split electrode plate (8) is adjusted to be above the z-axis of the reference coordinate system, thereby ensuring the accuracy of the value measured by the spatial position of the light beam.

5. The device for online nondestructive detection of extreme ultraviolet laser pulse energy and beam spatial position according to claim 1, characterized in that: When adjusting the needle valve (4), the intake amount of the rare gas needs to be strictly controlled so that the vacuum degree in the first ionization chamber and the second ionization chamber does not differ in magnitude before and after the intake of the gas, thereby completing non-destructive testing of the laser pulse energy and the spatial position of the light beam without affecting the use of the rear-end extreme ultraviolet laser.

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