Laser target anti-sputtering device and method

Abstract

The present invention discloses a laser target shooting anti-sputtering device and method, which is arranged between a focusing lens and a target, and comprises a rotatable rotating wheel, wherein a target shooting hole is arranged at a non-central position of the rotating wheel. During laser target shooting, the target shooting hole is located on the laser light path, so that the laser passes through the rotating wheel and bombards the target; after laser target shooting, the rotating wheel rotates so that the target shooting hole is rotated away from the laser light path, and the splash generated by the target shooting is blocked by the rotating wheel. The laser target shooting anti-sputtering device and method disclosed by the present invention can effectively block the splash generated by laser target shooting, and prevent the splash from damaging optical elements such as focusing lenses and reflective mirrors.

Description

Technical Field

[0001] The invention relates to a laser target shooting anti-sputtering device and method, and relates to the technical field of laser target shooting. Background Art

[0002] Laser target shooting refers to the process of high-power laser bombarding target materials. This process can be used to carry out many application research such as particle acceleration, extreme ultraviolet radiation generation, and sputtering coating.

[0003] During repetitive laser target shooting, due to the high repetition rate and high power of the laser, a large amount of high-temperature sputtering pollutants will be generated when interacting with the target. These pollutants include some clusters of splashes and molten droplets as large as micrometers, and also single particles as small as molecules or ions. For target fragments, particles, droplets, etc. with large mass, their general speed is 1 to 100 m / s, while the speed of splashes and high-energy ions with small mass is greater than 100 m / s, and can even reach 10 5 m / s. All of these sputtering objects may damage the high-precision optical components on the optical path. High-speed particles may hit the mirror surface and cause damage and scratches, while micron cluster droplets may deposit on the surface film of the device or cause erosion. These damages greatly reduce the reflection efficiency and focusing efficiency of the instrument for the laser, causing damage to the entire target shooting system.

[0004] Due to the vacuum environment of laser target shooting, the high-frequency operation of the laser, limited space and other factors, physical shielding is still the most suitable protection solution. Physical shielding requires moving the shielding plate at high speed after target shooting. However, the shielding plate needs to move from stationary to blocking the light path, which is subject to the starting acceleration process of the motor. The fastest time is still several milliseconds. During this time, the splashes of more than 100m / s generated by target shooting cannot be effectively blocked.

[0005] Therefore, it is necessary to conduct in-depth research on laser target anti-sputtering devices and methods to solve the above problems. Summary of the invention

[0006] In order to overcome the above problems, the inventors have conducted in-depth research and designed a laser target anti-sputtering device, which is arranged between the focusing lens and the target. The device includes a rotatable wheel, and a target hole is arranged at a non-central position of the wheel.

[0007] During laser target shooting, the target shooting hole is located on the laser light path, so that the laser passes through the rotating wheel and hits the target;

[0008] After laser target shooting, the rotating wheel rotates so that the target hole moves away from the laser light path, and the splashes generated by the target shooting are blocked by the rotating wheel.

[0009] In a preferred embodiment, the rotating wheels include at least two, and the plurality of rotating wheels are coaxially arranged, preferably arranged in parallel, and driven by the same motor.

[0010] In a preferred embodiment, the rotation speeds of multiple rotating wheels are the same, and each rotating wheel is provided with a circular targeting hole. By setting the distance from the center of the targeting hole of each rotating wheel to the center of the rotating wheel and the aperture of each targeting hole, the laser can pass through the targeting hole of each rotating wheel during laser targeting.

[0011] In a preferred embodiment, when there are two rotating wheels:

[0012] The distance L between the first rotor and the target is 10 cm, the distance r from the center point of the light path at the first rotor to the center of the first rotor is 20 cm, the aperture r1 of the targeting hole of the first rotor is 3 cm, the aperture r2 of the targeting hole of the second rotor is 3.69 cm, the rotation speed ω1 of the first rotor is 0.024 to 0.129 kr / s, the rotation speed ω2 of the second rotor is 0.024 to 0.129 kr / s, and the distance ΔL1 between the second rotor and the first rotor is 1 to 9 cm.

[0013] More preferably, the distance ΔL1 between the second rotating wheel and the first rotating wheel is 2.3 cm, the rotation speed ω1 of the first rotating wheel is 0.129 kr / s, and the rotation speed ω2 of the second rotating wheel is 0.129 kr / s.

[0014] In another preferred embodiment, when there are three rotating wheels:

[0015] The distance L between the first rotor and the target is 25 cm, the distance r from the center point of the optical path at the first rotor to the center of the first rotor is 20 cm, the aperture r1 of the targeting hole of the first rotor is 7.51 cm, the aperture r2 of the targeting hole of the second rotor is 8.11 cm, the aperture r3 of the targeting hole of the third rotor is 8.89 cm, the rotation speed ω1 of the first rotor is 0.023-0.150 kr / s, the rotation speed ω2 of the second rotor is 0.023-0.150 kr / s, the rotation speed ω3 of the third rotor is 0.023-0.150 kr / s, the distance ΔL1 between the second rotor and the first rotor is 1-9 cm, and the distance ΔL2 between the third rotor and the second rotor is 1-9 cm.

[0016] The invention also provides a laser target shooting anti-sputtering method, in which a rotatable rotating wheel is arranged between a focusing lens and a target, and a target shooting hole is arranged at a non-central position of the rotating wheel.

[0017] During laser target shooting, the target shooting hole is located on the laser light path, so that the laser passes through the rotating wheel and hits the target;

[0018] After laser target shooting, the rotating wheel rotates so that the target hole moves away from the laser light path, and the splashes generated by the target shooting are blocked by the rotating wheel.

[0019] In a preferred embodiment, the rotation speed of the rotating wheel, the size of the rotating wheel target hole, and the spacing between different rotating wheels are obtained by the following steps:

[0020] S1. Establish a model for the passing rate of the runner to the splashes;

[0021] S2. Set optimization goals;

[0022] S 3. Taking the optimization goal as the measurement indicator, conduct simulation experiments according to the pass rate model to obtain the optimal parameters.

[0023] In a preferred embodiment, the pass rate model in S1 can be expressed as:

[0024]

[0025] in, represents the passing rate, weight represents the overlapping area between the target hole of the first rotating wheel and the optical path, S eff represents the overlapping area of ​​the target holes of multiple rotating wheels, S represents the target hole area of ​​the first rotating wheel, and the first rotating wheel is the rotating wheel close to the target side.

[0026] In a preferred embodiment, in S2, the optimization target is set as: Max(Δv),

[0027] Where Δv = v high -αv low , v high Indicates the maximum speed of splashes that the model can block, v low It represents the minimum speed at which the model can block splashes, and α represents the weight.

[0028] The beneficial effects of the present invention include:

[0029] (1) It can effectively block the splashes generated by laser target shooting to prevent the splashes from damaging the optical components;

[0030] (2) The protective effect is high and good. It can completely block splashes of 0 to 100 m / s. The faster the rotation speed, the higher the speed of splashes that can be blocked. At a rotation speed of 150 r / s, it can completely block splashes of 0 to 600 m / s. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram showing laser targeting according to the present invention is shown;

[0032] Figure 2 A schematic structural diagram of a laser target anti-sputtering device according to a preferred embodiment of the present invention is shown;

[0033] Figure 3The simulation result of the shielding effect of the rotating wheel in the present invention is shown;

[0034] Figure 4 It shows that the passing rate of the first rotating wheel for splashing objects is not 0, the overlapping area between the first rotating wheel and the second rotating wheel is not 0, but the passing rate is 0;

[0035] Figure 5 The meaning of Δv in the optimization target setting of the present invention is shown;

[0036] Figure 6 A schematic diagram showing the process of using the Bayesian method multiple times to obtain the optimal result;

[0037] Figure 7 The result diagram obtained by the full-space scanning method of the present invention is shown;

[0038] Figure 8 A schematic diagram showing the blocking effect of two wheels on splashing objects in a preferred embodiment of the present invention;

[0039] Fig. 9 A schematic diagram showing the blocking effect of three wheels on splashing objects in a preferred embodiment of the present invention is shown. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present invention will become more clear and distinct.

[0041] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0042] Figure 1 A schematic diagram of laser target shooting is shown, in which the laser is reflected by multiple reflectors to a focusing mirror, and is focused by the focusing mirror, and the focused laser hits the target.

[0043] A laser target shooting anti-sputtering device provided by the present invention is arranged between a focusing lens and a target, and is used to shield splashes caused by target shooting to prevent the splashes from damaging high-precision optical elements on the optical path.

[0044] Furthermore, since the shielding plate blocks the light path from being stationary, it still takes several milliseconds at the fastest due to the starting acceleration process of the motor. The inventor was inspired by the high-speed and stable rotation of the magnetic disk in the hard disk and used a high-speed rotating wheel to block the splashing objects.

[0045] Specifically, the laser target anti-sputtering device includes a rotating wheel, and a target hole is arranged at a non-central position of the rotating wheel, such as Figure 2shown.

[0046] During the target shooting process, the rotating wheel is always rotating. By setting an appropriate rotation speed, when target shooting is required, the light path is located in the target hole, and the laser passes through the rotating wheel from the target hole to bombard the target; after the target shooting is completed, the target hole is rotated away from the light path, and the splashes generated by the target shooting are blocked by the rotating wheel.

[0047] Since different splashes have different speeds, the rotation of a single wheel can block splashes at some speeds. Since the wheel rotates periodically, the target hole is placed in the light path every time it rotates, which allows some splashes to pass through the wheel. The simulation results of the shielding effect of the wheel are shown in Figure 2. Figure 3 As shown, the horizontal axis represents the splashes at different speeds, and the vertical axis represents the penetration rate of the splashes, that is, the proportion of the splashes passing through the rotor.

[0048] pass Figure 3 It can be found that a single rotor can block most of the splashes, but there are a large number of peaks in the curve, and the splashes corresponding to the peaks are not blocked, especially the splashes with a speed lower than 100 m / s are largely penetrated.

[0049] Furthermore, the rotating wheels include at least two, multiple rotating wheels are coaxially arranged, preferably parallelly arranged, and driven by the same motor. By arranging multiple rotating wheels, splashing objects are blocked multiple times, thereby further reducing splashing objects.

[0050] Furthermore, each rotating wheel is provided with a circular targeting hole, and by setting the distance from the center of the targeting hole of each rotating wheel to the center of the rotating wheel (axis) and the aperture of each targeting hole, the laser can pass through the targeting hole of each rotating wheel during laser targeting.

[0051] Preferably, the center point of the light path at the rotating wheel overlaps with the center of the rotating wheel.

[0052] In a preferred embodiment, since the light path is a cone with the target as the vertex, the farther away from the target, the larger the cross-section of the light path. In the present invention, the targeting holes of different rotating wheels have different radii, and the radius of the targeting hole of the rotating wheel closer to the target is smaller.

[0053] According to the present invention, since splashes with a speed of 1 to 100 m / s are of larger mass, they are more destructive to optical instruments. Therefore, it is expected to completely block this part of the splashes. In addition, for splashes with a speed of 100 to 1000 m / s, it is also expected to achieve a better interception effect. How to set parameters such as different wheel rotation speeds, different wheel target hole apertures, different wheel spacings, and the distance between the wheel and the target to achieve the best shielding effect is the difficulty of the present invention.

[0054] Among these parameters, the meaning of the wheel speed is relatively clear, and two ideas can be tried. For example, when two wheels are used: the first idea is to set the speed ω1 of one wheel to a low speed to block low-speed splashes, and the speed ω2 of the other wheel is set to a high speed to block high-speed splashes; the second idea is to set both wheels to a high speed, and the speed difference between the two wheels is small, so that the overlap time of the two wheels is long each time. However, it is still difficult to determine how to set the speed and what speed to set to achieve the optimal effect by just a limited number of experiments.

[0055] In addition, it is difficult to find experimental basis for parameters such as the wheel spacing ΔL, the sizes of the two wheel target holes r1 and r2, and the distance L between the wheel and the target. It is difficult to adjust the parameters and it is difficult to determine them through multiple tests.

[0056] In the present invention, the optimal parameters are found in a wide parameter space by using an optimization algorithm.

[0057] Specifically, the steps include:

[0058] S1. Establish a model for the passing rate of the runner to the splashes;

[0059] S2. Set optimization goals;

[0060] S3. Taking the optimization target as the measurement indicator, conduct simulation experiments according to the pass rate model to obtain the optimal parameters.

[0061] In S1, since the overlapping area of ​​more than three circles is very complicated and there is no calculation formula, while the calculation of the overlapping area of ​​two circles is very simple, in the present invention, the pass rate model adopts some approximate values. First, the overlapping area of ​​the target hole of the first rotating wheel and the light path is calculated, that is, the pass rate weight of the first rotating wheel for the splashes, and then the overlapping area of ​​the first rotating wheel and other rotating wheels is calculated. If weight = 0, then obviously, the splashes will not be able to fly to the second rotating wheel at this time.

[0062] The pass rate model can be expressed as:

[0063]

[0064] in, represents the passing rate, weight represents the overlapping area between the target hole of the first rotating wheel and the optical path, S eff represents the overlapping area of ​​the target holes of multiple rotating wheels, S represents the target hole area of ​​the first rotating wheel, and the first rotating wheel is the rotating wheel close to the target side.

[0065] This model can achieve uniform distribution of target sputtering in the optical path.

[0066] Furthermore, the weight can be measured by the center of the first rotating wheel target hole. The aperture r1 and the optical path are obtained at the center point of the first rotating wheel, where the center of the first rotating wheel target hole is The position can be expressed as:

[0067]

[0068] ω1 represents the rotation speed of the first wheel, t represents time, Represents the unit vectors in all directions of the system.

[0069] Similarly, the position of the center point of the optical path is:

[0070]

[0071] The light path is stationary and its position does not change with time.

[0072] According to the position of the two circles The overlapping area of ​​the two circles can be obtained through geometric formulas and can be expressed as but It can be expressed as

[0073] Similarly, the center of the kth wheel target hole The position can be expressed as:

[0074]

[0075] S eff represents the overlapping area between the target holes of the rotating wheel. If there are k rotating wheels, according to the position of each target hole at that moment and its corresponding aperture r k , k∈[1,n], S eff It can be expressed as:

[0076] Calculate the overlapping area between n wheels and take the minimum value.

[0077] S is the area of ​​the first target hole, which is approximately equal to the area of ​​the optical path and represents the total amount of incident spatter. In this model, through approximate calculation, a pass rate can be obtained relatively simply and quickly, but there is a problem with this pass rate, that is, when weight≠0, S eff ≠0, the actual pass rate may also be 0, such as Figure 4 As shown in the figure, the passing rate calculated by the model is not 0, that is, the splashes that should have been blocked are considered to have passed through the device in the model. However, this approximation will only underestimate the blocking effect of the wheel and will not cause other effects.

[0078] More preferably, the overlapping area S of the plurality of rotating wheel target holes is effWhen calculating, the minimum value of the overlapping area between multiple rotating wheel target holes is taken. This approximate method will also underestimate the blocking effect of the rotating wheel, that is, the actual blocking effect is better than the model calculation effect.

[0079] According to the present invention, when setting the optimization target, we expect that all low-speed (less than 100 m / s) splashes are blocked, and high-speed (greater than or equal to 100 m / s) splashes are blocked as much as possible. The more high-speed splashes are blocked, the closer to the target.

[0080] Further, based on this, in S2, the optimization target is set to: Max(Δv).

[0081] Where Δv = v high -αv low , v high Indicates the maximum speed of splashes that the model can block, v low It represents the minimum speed at which the model can block splashes, and α represents the weight. The schematic diagram is as follows Figure 5 shown.

[0082] Since the primary optimization goal is to ensure no leakage at low speed, the two speeds v in Δv are high 、v low The influence of should not be the same. In the present invention, by adding weight α, the optimization objective is to satisfy v first. low Lower, then consider v high higher.

[0083] Based on multiple experiments, the weight α is taken as 575.

[0084] In S3, for any set of ω k , r k , r, L, according to the pass rate model, the pass rate of splashes with different speeds v passing through the device can be simulated. Taking the optimization target as the measurement indicator, the optimal parameters can be obtained through the function optimization method.

[0085] In the present invention, the specific method of the function optimization method is not particularly limited. Preferably, the Bayesian optimization method is used. The Bayesian method can be specifically referred to in the paper MATTHIAS, SEEGER..GAUSSIAN PROCESSES FORMACHINELEARNING[J].International Journal of Neural Systems, 2004.

[0086] The inventors found that although the Bayesian method is powerful and efficient, there are many points that meet the optimization goal in a wide parameter domain. The Bayesian algorithm can only find some of them randomly, and the results are very rough. In addition, Bayesian optimization tends to converge to a local maximum. If used improperly, the Bayesian algorithm cannot find a usable solution, and its effect is even worse than random search.

[0087] In a more preferred embodiment, each time the Bayesian method is used, the optimal parameters are not directly obtained, but the parameters with poor results are excluded to narrow the parameter domain, so that the optimal result is obtained by using the Bayesian method multiple times, such as Figure 6 shown.

[0088] The use of the Bayesian method can greatly reduce the amount of optimization calculations, save optimization time, and the optimization effect is more accurate.

[0089] In order to verify the accuracy of the Bayesian method, the inventors also used the full space scanning method to test the optimization results. Figure 7 As shown in the figure, black indicates that the rotor has leakage to low-speed splashes, gray indicates that although the rotor can completely block low-speed splashes, the maximum blocking speed does not exceed 100m / s, and white indicates that the rotor performance fully meets the protection requirements. The optimization results obtained based on the full-space scanning results are exactly the same as those obtained by the Bayesian method. Furthermore, 10,000 points were scanned in the full-space scanning diagram, while only 300 points were calculated by the Bayesian optimization, which indirectly illustrates the high efficiency of the Bayesian optimization.

[0090] According to the present invention, through optimization, the inventors found that setting the rotation speeds of multiple wheels to be the same can better block splashes and reduce the splash passing rate, which is contrary to people's habitual thinking.

[0091] Furthermore, the rotation speeds of the multiple wheels are the same, which can simplify the structure of the wheels. This function can be achieved by simply installing the multiple wheels on the same rotating shaft.

[0092] Furthermore, through the optimization process, the inventors determined the final optimal parameters, specifically,

[0093] When there are two wheels:

[0094] The distance L between the first rotor and the target is 10 cm, the radius r of the light path at the targeting hole of the first rotor is 20 cm, the aperture r1 of the targeting hole of the first rotor is 3 cm, the aperture r2 of the targeting hole of the second rotor is 3.69 cm, the rotation speed ω1 of the first rotor is 0.024 to 0.129 kr / s, the rotation speed ω2 of the second rotor is 0.024 to 0.129 kr / s, and the distance ΔL1 between the second rotor and the first rotor is 1 to 9 cm.

[0095] Under this parameter, splashes with speeds between 0 and 100 m / s can be blocked.

[0096] More preferably, the distance between the second wheel and the first wheel is ΔL1=2.3 cm, the rotation speed of the first wheel is ω1=0.129 kr / s, and the rotation speed of the second wheel is ω2=0.129 kr / s. The inventors found that the greater the rotation speed of the wheel, the greater the maximum speed of the splashes it can intercept. Therefore, the wheel speed takes the maximum possible speed, thereby obtaining the optimal wheel spacing.

[0097] Under the above parameters, the device has the following blocking effect on splashes: Figure 8 As shown, the blocking effect is very ideal, and splashes of 0 to 526 m / s can be completely blocked.

[0098] When there are three wheels:

[0099] The distance L between the first rotor and the target is 25 cm, the radius r of the light path at the targeting hole of the first rotor is 20 cm, the aperture r1 of the targeting hole of the first rotor is 7.51 cm, the aperture r2 of the targeting hole of the second rotor is 8.11 cm, the aperture r3 of the targeting hole of the third rotor is 8.89 cm, the rotation speed ω1 of the first rotor is 0.023-0.150 kr / s, the rotation speed ω2 of the second rotor is 0.023-0.150 kr / s, the rotation speed ω3 of the third rotor is 0.023-0.150 kr / s, the distance ΔL1 between the second rotor and the first rotor is 1-9 cm, and the distance ΔL2 between the third rotor and the second rotor is 1-9 cm.

[0100] Under this parameter, splashes with speeds between 0 and 100 m / s can be blocked.

[0101] More preferably, the rotation speed of the first wheel ω1 = 0.150 kr / s, the rotation speed of the second wheel ω2 = 0.150 kr / s, the rotation speed of the third wheel ω3 = 0.150 kr / s, the distance between the second wheel and the first wheel ΔL1 = 2.0 cm, and the distance between the third wheel and the second wheel ΔL1 = 2.6 cm.

[0102] Under the above parameters, the device has the following blocking effect on splashes: Fig. 9 As shown, the blocking effect is very ideal, and splashes of 0 to 617 m / s can be completely blocked.

[0103] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", etc. indicate positions or positional relationships based on the working state of the present invention, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", and "fourth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0104] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0105] The present invention has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, the present invention may be subjected to a variety of substitutions and improvements, all of which fall within the scope of protection of the present invention.

Claims

1. A laser target anti-sputtering device, characterized in that: The device is arranged between the focusing lens and the target, and comprises a rotatable wheel, and a target hole is arranged at a non-central position of the wheel. During laser target shooting, the target shooting hole is located on the laser light path, so that the laser passes through the rotating wheel and hits the target; After laser target shooting, the rotating wheel rotates so that the target hole moves away from the laser light path, and the splashes generated by the target shooting are blocked by the rotating wheel; The rotating wheels include at least two, and the plurality of rotating wheels are coaxially arranged and driven by the same motor; The rotation speeds of the multiple rotating wheels are the same, and each rotating wheel is provided with a circular target hole. By setting the distance from the center of the target hole of each rotating wheel to the center of the rotating wheel and the aperture of each target hole, the laser can pass through the target hole of each rotating wheel during laser target shooting; The rotation speed of the rotating wheel, the size of the rotating wheel target hole and the spacing between different rotating wheels are obtained by the following method: S1. Establish a model for the passing rate of the runner to the splashes; S2. Set optimization goals; S 3. Taking the optimization goal as the measurement indicator, conduct simulation experiments according to the pass rate model to obtain the optimal parameters; The pass rate model described in S1 is expressed as: in, represents the passing rate, weight represents the overlapping area between the target hole of the first rotating wheel and the optical path, S eff represents the overlapping area of ​​the target holes of multiple rotating wheels, S represents the target hole area of ​​the first rotating wheel, and the first rotating wheel is the rotating wheel close to the target side; In S2, the optimization target is set as: Max(Δv), Where Δv = v high -αv low , v high Indicates the maximum speed of splashes that the model can block, v low It represents the minimum speed at which the model can block splashes, and α represents the weight.

2. The laser target anti-sputtering device according to claim 1, characterized in that: When there are two wheels: The distance L between the first rotor and the target is 10 cm, the distance r from the center point of the light path at the first rotor to the center of the first rotor is 20 cm, the aperture r1 of the targeting hole of the first rotor is 3 cm, the aperture r2 of the targeting hole of the second rotor is 3.69 cm, the rotation speed ω1 of the first rotor is 0.024 to 0.129 kr / s, the rotation speed ω2 of the second rotor is 0.024 to 0.129 kr / s, and the distance ΔL1 between the second rotor and the first rotor is 1 to 9 cm.

3. The laser target anti-sputtering device according to claim 2, characterized in that: The distance between the second rotating wheel and the first rotating wheel is ΔL1=2.3 cm, the rotation speed of the first rotating wheel is ω1=0.129 kr / s, and the rotation speed of the second rotating wheel is ω2=0.129 kr / s.

4. The laser target anti-sputtering device according to claim 1, characterized in that: When there are three wheels: The distance L between the first rotor and the target is 25 cm, the distance r from the center point of the optical path at the first rotor to the center of the first rotor is 20 cm, the aperture r1 of the targeting hole of the first rotor is 7.51 cm, the aperture r2 of the targeting hole of the second rotor is 8.11 cm, the aperture r3 of the targeting hole of the third rotor is 8.89 cm, the rotation speed ω1 of the first rotor is 0.023-0.150 kr / s, the rotation speed ω2 of the second rotor is 0.023-0.150 kr / s, the rotation speed ω3 of the third rotor is 0.023-0.150 kr / s, the distance ΔL1 between the second rotor and the first rotor is 1-9 cm, and the distance ΔL2 between the third rotor and the second rotor is 1-9 cm.

5. A laser target anti-sputtering method, characterized in that: A rotatable wheel is arranged between the focusing lens and the target, and a target hole is arranged at a non-center position of the wheel. During laser target shooting, the target shooting hole is located on the laser light path, so that the laser passes through the rotating wheel and hits the target; After laser target shooting, the rotating wheel rotates so that the target hole moves away from the laser light path, and the splashes generated by the target shooting are blocked by the rotating wheel; The following steps are used to obtain the rotation speed of the wheel, the size of the wheel target hole, and the spacing between different wheels: S1. Establish a model for the passing rate of the runner to the splashes; S2. Set optimization goals; S 3. Taking the optimization goal as the measurement indicator, conduct simulation experiments according to the pass rate model to obtain the optimal parameters; The pass rate model described in S1 is expressed as: in, represents the passing rate, weight represents the overlapping area between the target hole of the first rotating wheel and the optical path, S eff represents the overlapping area of ​​the target holes of multiple rotating wheels, S represents the target hole area of ​​the first rotating wheel, and the first rotating wheel is the rotating wheel close to the target side; In S2, the optimization target is set as: Max(Δv), Where Δv = v high -αv low , v high Indicates the maximum speed of splashes that the model can block, v low It represents the minimum speed at which the model can block splashes, and α represents the weight.

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