Radiation beam line purging structure based on beam limiting hole and upstream differential air exhaust

Abstract

The invention relates to a radiation beam line purging structure based on a beam limiting hole and upstream differential air exhaust, and the structure comprises a beam line channel which is used for the axial transmission of radiation; the at least two beam limiting holes are arranged at intervals along the radiation propagation direction of the beam line channel and comprise a first beam limiting hole and a second beam limiting hole; the gas introduction port is used for introducing purging gas into the bunching channel; an extraction opening provided on the upstream side of the gas introduction opening and used for extracting the purge gas; and the relative positions of the extraction opening and the gas introduction opening are configured to enable the introduced purging gas to form directional gas flow pointing to the radiation source direction in an area between the first beam limiting hole and the second beam limiting hole. The device has the beneficial effects that through the synergistic effect of beam limiting hole constraint and upstream differential gas extraction, a stable reverse gas flow field pointing to the radiation source direction is formed in a beam line, and active interception and blocking can be carried out before pollutants enter a downstream key area.

Description

Technical Field

[0001] This invention belongs to the field of high-energy radiation beamline technology, and particularly relates to a radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping. Background Technology

[0002] In applications of plasma radiation sources and other high-energy radiation sources, radiation typically needs to be transmitted downstream through beamline channels for spectral measurements or optical applications. During operation, the radiation source generates neutral atoms, low-energy particles, and reaction products, which readily propagate downstream along the beamline.

[0003] The aforementioned contaminants can absorb radiation, reducing the effective radiation intensity measured at the back end of the beamline. Furthermore, the deposition of contaminants on the surfaces of downstream optical components (such as filter films and multilayer mirrors) can lead to optical performance degradation, severely affecting component lifespan and system stability.

[0004] In existing technologies, contamination problems are typically mitigated by increasing the overall vacuum level or introducing simple gas purging into the beamline. However, simple purging often fails to create an effective contamination barrier interface and may even push the gas further downstream into the optical region, thereby increasing radiation absorption and accelerating contamination of optical components.

[0005] Therefore, there is an urgent need for a beamline structure design that can effectively block contaminants from the radiation source side from entering the downstream region of the beamline without significantly increasing radiation absorption. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping.

[0007] Firstly, a radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping is provided, including: The beam channel is used to allow radiation to propagate axially; At least two beam-limiting apertures are provided at intervals along the radiation propagation direction of the beamline channel, including a first beam-limiting aperture and a second beam-limiting aperture; A gas inlet is provided between or near the first and second beam-limiting holes for introducing purge gas into the beam channel. An exhaust port is located upstream of the gas inlet and is used to extract the purging gas. The relative positions of the exhaust port and the gas inlet are configured such that the introduced purge gas forms a directional gas flow pointing towards the radiation source in the region between the first and second beam-limiting apertures.

[0008] Preferably, the purging gas is an inert gas.

[0009] Preferably, the apertures of the first and second beam-limiting apertures are set according to the spot size of the radiation beam to constrain the gas distribution space within the beamline.

[0010] Preferably, the exhaust port and the gas inlet are arranged asymmetrically in the axial direction.

[0011] Preferably, the exhaust port is closer to the gas inlet in the axial direction relative to the radiation source side.

[0012] Preferably, the diameters of the first and second beam-limiting apertures are equal.

[0013] Secondly, a radiation beamline purging method based on a beam-limiting aperture and upstream differential pumping is provided, executed by any of the structures described in the first aspect, including: S1. Provide a radiation beamline channel, and provide a first beam-limiting aperture and a second beam-limiting aperture at intervals along the radiation propagation direction inside it; S2. A gas inlet is provided in the area between or near the first beam-limiting hole and the second beam-limiting hole, and an exhaust port is provided on the upstream side of the gas inlet. S3. Purge gas is introduced into the wire harness channel through the gas inlet; S4. Air is drawn through the air extraction port, so that the purge gas forms a directional gas flow pointing towards the radiation source in the area between the first and second beam-limiting holes, thereby blocking the downstream migration of pollutants from the radiation source side.

[0014] Preferably, in S1, the number of beam-limiting holes is two or more.

[0015] Preferably, in step S3, the purging gas is an inert gas.

[0016] The beneficial effects of this invention are: 1. This invention, through the synergistic effect of beam-limiting aperture constraint and upstream differential pumping, forms a stable, reverse gas flow field inside the beamline, pointing towards the radiation source. This actively intercepts and blocks contaminants before they enter critical downstream areas. This not only significantly reduces the contamination load downstream of the beamline but also fundamentally slows down the contamination deposition rate on the surface of downstream optical components, thereby effectively extending their service life and improving the long-term stability and reliability of the entire system.

[0017] 2. This invention, while introducing gas for contamination control, avoids the additional radiation absorption problems that may arise from traditional simple purging by optimizing the gas distribution and flow path within the beamline. Under reasonable structure and operating conditions, it can improve the gas composition within the beamline, enabling not only the effective radiation intensity detected at the rear end of the beamline to be maintained, but potentially even significantly improved.

[0018] 3. The core of this invention lies in the relative positional layout of the beam confinement aperture, gas inlet, and upstream extraction port, without requiring complex external devices or significant modifications to the beamline body. The structural design principle is clear, and engineering implementation is simple, mainly involving adjustments to the internal aperture arrangement and standard gas interface. Therefore, it can be integrated into existing radiation beamline systems at low cost and high efficiency. Attached Figure Description

[0019] Figure 1 This is an overall schematic diagram of the radiation beamline purging structure provided by the present invention. Figure 2 This is a schematic diagram showing the relative positions of the beam-limiting hole, gas inlet, and upstream exhaust port in the beam channel provided by the present invention. Explanation of reference numerals in the attached diagram: 1. Beam channel; 2. First beam limiting aperture; 3. Second beam limiting aperture; 4. Gas inlet; 5. Gas extraction port; 6. Pollutant; 7. Radiation source side; 8. Downstream optical element; 9. Radiation propagation direction; 10. Directional gas flow field; 11. Reverse gas flow field. Detailed Implementation

[0020] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that those skilled in the art can make several modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0021] Example 1: Embodiment 1 of this application provides a radiation beamline purging structure based on a beam-limiting aperture and upstream differential evacuation. By rationally arranging the beam-limiting aperture, gas inlet, and evacuation port located upstream of it within the beamline channel, a directional gas flow region pointing towards the radiation source is formed inside the beamline. This achieves the following: actively blocking the downstream propagation of contaminant particles from the radiation source side; maintaining or even increasing the radiation intensity measured at the rear end of the beamline when gas purging is introduced; and significantly reducing the contamination rate of downstream optical components, thus extending their service life.

[0022] Specifically, such as Figure 1 and Figure 2 As shown, the radiation beamline purging structure provided in Embodiment 1 of this application includes: Beam channel 1 is used to allow radiation to propagate axially; At least two beam-limiting apertures are provided at intervals along the radiation propagation direction of the beamline channel 1, including a first beam-limiting aperture 2 and a second beam-limiting aperture 3; Gas inlet 4 is located between or near the first beam-limiting hole 2 and the second beam-limiting hole 3, and is used to introduce purge gas into the beam channel 1. The exhaust port 5 is located upstream of the gas inlet 4 and is used to extract the purging gas. The relative positions of the exhaust port 5 and the gas inlet port 4 are configured such that the introduced purge gas forms a directional gas flow pointing towards the radiation source in the region between the first beam-limiting aperture 2 and the second beam-limiting aperture 3.

[0023] As can be seen, this application constrains the beamline space by using beam-limiting apertures, introduces purge gas between the beam-limiting apertures, and extracts gas on the upstream side, so that the introduced gas forms a directional reverse gas flow region inside the beamline pointing towards the radiation source, thereby constructing a local gas curtain inside the beamline and achieving active suppression of upstream pollutants migrating downstream.

[0024] This approach is not a simple purging method, but an active contamination suppression method that combines bundle geometry with differential pumping.

[0025] Example 2: Based on Embodiment 1, Embodiment 2 of this application provides a more specific radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping, including: Beam channel 1 is used to allow radiation to propagate axially; At least two beam-limiting apertures are provided at intervals along the radiation propagation direction of the beamline channel 1, including a first beam-limiting aperture 2 and a second beam-limiting aperture 3; Gas inlet 4 is located between or near the first beam-limiting hole 2 and the second beam-limiting hole 3, and is used to introduce purge gas into the beam channel 1. The exhaust port 5 is located upstream of the gas inlet 4 and is used to extract the purging gas. The relative positions of the exhaust port 5 and the gas inlet port 4 are configured such that the introduced purge gas forms a directional gas flow pointing towards the radiation source in the region between the first beam-limiting aperture 2 and the second beam-limiting aperture 3.

[0026] The formation of the directional gas flow region is mainly influenced by the combined effects of the constraint of the aperture geometry and the relative position of the gas inlet and the upstream extraction port. It can be achieved within a reasonable operating range without limiting the specific gas pressure, flow rate or aperture ratio.

[0027] Furthermore, the purging gas is an inert gas.

[0028] The first beam-limiting aperture 2 and the second beam-limiting aperture 3 maintain a certain axial distance, and the aperture diameters of both are set according to the spot size of the radiation beam. This is used to limit the cross-sectional size of the radiation beam so that the radiation beam can pass through smoothly, while also constraining the gas distribution within the beamline.

[0029] The exhaust port 5 and the gas inlet 4 are arranged asymmetrically in the axial direction to enhance the flow tendency of gas in the opposite direction of radiation propagation.

[0030] The exhaust port 5 is closer to the gas inlet port 4 in the axial direction relative to the radiation source side.

[0031] The diameters of the first beam-limiting aperture 2 and the second beam-limiting aperture 3 are equal.

[0032] With the above structure, by constraining the beamline space through the beam-limiting aperture and through the synergistic effect of the gas inlet and the upstream exhaust port, a stable reverse gas flow region can be formed inside the beamline. This improves the radiation transmission conditions at the back end of the beamline without significantly increasing radiation absorption and reduces the risk of contamination of downstream optical components.

[0033] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 1 can be referred to each other, and will not be repeated in this application.

[0034] Example 3: Based on Embodiment 2, Embodiment 3 of this application provides a radiation beamline purging method based on a beam-limiting aperture and upstream differential pumping, executed by any of the structures described in the first aspect, including: S1. Provide a radiation beamline channel 1, and provide a first beam-limiting aperture 2 and a second beam-limiting aperture 3 at intervals along the radiation propagation direction inside it.

[0035] In S1, the number of beam-limiting apertures is two or more.

[0036] S2. A gas inlet 4 is provided in the area between or near the first beam-limiting hole 2 and the second beam-limiting hole 3, and an exhaust port 5 is provided on the upstream side of the gas inlet 4.

[0037] S3. Purge gas is introduced into the wire channel 1 through the gas inlet 4.

[0038] In S3, the purging gas is an inert gas.

[0039] S4. Air is drawn through the air extraction port 5, so that the purge gas forms a directional gas flow pointing towards the radiation source in the area between the first beam-limiting hole 2 and the second beam-limiting hole 3, thereby blocking the downstream migration of pollutants from the radiation source side.

[0040] In the above method, the purge gas enters the beamline channel 1 through the gas inlet 4 and forms a directional gas flow region in the opposite direction of radiation propagation under the action of the exhaust port 5 located upstream of it.

[0041] The beam-limiting aperture restricts the lateral expansion of the gas flow region, ensuring that the gas is mainly distributed between and near the aperture, thus forming a stable local gas curtain within the beamline. This gas curtain effectively blocks residual gas, contaminant particles, or reaction products from the radiation source side from entering the downstream region of the beamline.

[0042] It should be noted that the method provided in this embodiment is the corresponding method for the structure provided in embodiment 2. Therefore, the parts that are the same as or similar to those in embodiment 2 in this embodiment can be referred to each other, and will not be described again in this application.

[0043] In summary, this application introduces a purging structure based on a beam-limiting aperture and upstream differential pumping into the radiation beamline, forming a stable reverse gas curtain within the beamline and achieving active blocking of upstream contamination. This invention is a structural and mechanistic invention; its technical effects are explained based on the directional gas flow mechanism formed by the beam-limiting aperture and upstream differential pumping. The relevant effects have been described in the specification from the perspective of structure and working principle, without limiting specific experimental or simulation data.

Claims

1. A radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping, characterized in that, include: The beam channel (1) is used to allow radiation to propagate along the axial direction; At least two beam-limiting apertures are provided at intervals along the radiation propagation direction of the beamline channel (1), including a first beam-limiting aperture (2) and a second beam-limiting aperture (3). A gas inlet (4) is provided between or near the first beam-limiting hole (2) and the second beam-limiting hole (3) for introducing purge gas into the beam channel (1); The exhaust port (5) is located upstream of the gas inlet (4) and is used to extract the purging gas. The relative positions of the exhaust port (5) and the gas inlet (4) are configured such that the introduced purge gas forms a directional gas flow pointing towards the radiation source in the region between the first beam-limiting aperture (2) and the second beam-limiting aperture (3).

2. The radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping as described in claim 1, characterized in that, The purging gas is an inert gas.

3. The radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping as described in claim 2, characterized in that, The apertures of the first beam-limiting aperture (2) and the second beam-limiting aperture (3) are set according to the spot size of the radiation beam and are used to constrain the gas distribution space within the beamline.

4. The radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping as described in claim 3, characterized in that, The exhaust port (5) and the gas inlet (4) are arranged asymmetrically in the axial direction.

5. The radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping as described in claim 4, characterized in that, The extraction port (5) is closer to the gas inlet (4) in the axial direction relative to the radiation source side.

6. The radiation beamline purging structure based on a beam-limiting aperture and upstream differential pumping as described in claim 4, characterized in that, The diameters of the first beam-limiting aperture (2) and the second beam-limiting aperture (3) are equal.

7. A radiation beamline purging method based on a beam-limiting aperture and upstream differential pumping, characterized in that, Performed by the structure according to any one of claims 1 to 6, comprising: S1. Provide a radiation beamline channel (1), and provide a first beam-limiting aperture (2) and a second beam-limiting aperture (3) at intervals along the radiation propagation direction inside it; S2. A gas inlet (4) is provided in the area between or near the first beam-limiting hole (2) and the second beam-limiting hole (3), and an exhaust port (5) is provided on the upstream side of the gas inlet (4). S3. Purge gas is introduced into the wire channel (1) through the gas inlet (4); S4. By drawing air through the air extraction port (5), the purge gas forms a directional gas flow pointing towards the radiation source in the area between the first beam-limiting hole (2) and the second beam-limiting hole (3), thereby blocking the downstream migration of pollutants from the radiation source side.

8. The radiation beamline purging method based on a beam-limiting aperture and upstream differential pumping according to claim 7, characterized in that, In S1, the number of beam-limiting apertures is two or more.

9. The radiation beamline purging method based on a beam-limiting aperture and upstream differential pumping according to claim 7, characterized in that, In S3, the purging gas is an inert gas.

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