Electron beam parameter measuring device and electron beam parameter measuring method

Abstract

The present invention relates to the field of electron beam measurement technology, and in particular to an electron beam parameter measurement device and an electron beam parameter measurement method. An electron beam parameter measurement device comprises: a multilayer board with a micro-device array structure, wherein a plurality of array-distributed Faraday cup assemblies are arranged on the multilayer board, each of the Faraday cup assemblies comprises at least two coaxially arranged Faraday cups, and at least two of the Faraday cups are arranged through, and the electron beam is injected into the Faraday cup of the lower layer through the Faraday cup of the upper layer, and the electron beam current size of each layer of the Faraday cup is obtained to obtain the corresponding parameters of the electron beam. The present invention provides an electron beam parameter measurement device and an electron beam parameter measurement method that can be measured quickly.

Description

Technical Field

[0001] The present invention relates to the technical field of electron beam measurement, and in particular to an electron beam parameter measurement device and an electron beam parameter measurement method. Background Art

[0002] Electron beams are electrons gathered into a beam with high energy density. Electron beam devices are widely used in many fields such as high-resolution microscopy, micro-machining, diffraction imaging, satellite communications and high-energy physics. Electron beam parameters such as beam spot, beam current, divergence angle, beam current density are key performance indicators of electron beam devices. Measuring electron beam parameters is of great significance for monitoring device performance and quantitatively evaluating electron guns and their electron optical design. Common methods for measuring electron beam performance include the fluorescent screen method, cross-wire method, multi-slit method, single-slit method, single-hole method, pepper hole method, etc., but these methods have problems such as low measurement accuracy, slow speed, and single parameters.

[0003] There is an existing electron beam profile and intensity distribution measuring instrument, which sequentially arranges an aperture plate, an insulating ring, a Faraday cage and an insulating base. The central hole of the aperture plate is driven by a stepper motor to sweep across the beam spot, thereby receiving a signal to obtain the electron beam profile and intensity distribution. However, the aperture plate needs to be driven by a stepper motor to sweep across the beam spot. The stepper motor drive not only has errors, but also takes a long time to measure due to the small displacement when sweeping the beam spot. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art that the measurement time is too long due to the small displacement of the driving mechanism, thereby providing an electron beam parameter measurement device and electron beam parameter measurement method that can measure quickly.

[0005] In order to solve the above technical problems, the present invention provides an electron beam parameter measuring device, comprising:

[0006] A multilayer board with a micro-device array structure is provided with a plurality of Faraday cup assemblies distributed in an array, each of the Faraday cup assemblies comprises at least two coaxially arranged Faraday cups, at least two of the Faraday cups are arranged through, an electron beam is injected into the Faraday cup of the lower layer through the Faraday cup of the upper layer, and the electron beam current size of the Faraday cup of each layer is obtained to obtain the corresponding parameters of the electron beam.

[0007] Optionally, the Faraday cup assemblies in two adjacent rows are staggered and the spacing between every two Faraday cup assemblies is equal.

[0008] Optionally, the Faraday cup includes an aperture plate, a first insulating plate and a cup body which are sequentially arranged along the irradiation direction of the electron beam, a first through hole is opened at the center of the aperture plate, a second through hole is opened at the center of the first insulating plate, a third through hole is opened at the bottom of the cup body, the first through hole and the third through hole have the same inner diameter, the second through hole has the same inner diameter as the cup body and is larger than the first through hole and the third through hole, so that after a part of the electron beam is received by the upper Faraday cup, the remaining part is received by the lower Faraday cup.

[0009] Optionally, a second insulating plate is further included which is arranged on the outer periphery of the Faraday cup.

[0010] Optionally, the aperture plate is made of molybdenum or tungsten, the first insulating plate and the second insulating plate are made of silicon dioxide or silicon nitride, and the cup body is made of molybdenum, tungsten or copper.

[0011] Optionally, the inner diameters of the first through hole and the third through hole are 10 nm-1 μm, and the inner diameters of the second through hole and the cup body are 20 nm-2 μm.

[0012] Optionally, each set of the Faraday cup assemblies includes two coaxially arranged Faraday cups.

[0013] A method for measuring electron beam parameters is also provided, which uses the electron beam parameter measuring device of the present invention, and comprises the following steps:

[0014] The electron beam is irradiated vertically toward the Faraday cup assembly of the multilayer board, so that the electron beam is sequentially injected into the Faraday cup of the lower layer through the upper Faraday cup, and the electron beam current size of each Faraday cup of each layer in each Faraday cup assembly is obtained to obtain the corresponding parameters of the electron beam. A method for measuring electron beam parameters is also provided, which uses the electron beam parameter measuring device of the present invention, and includes the following steps:

[0015] The electron beam is irradiated vertically toward the Faraday cup assembly of the multilayer board, so that the electron beam is sequentially injected into the Faraday cup of the lower layer through the upper layer Faraday cup, and the electron beam current size I of each layer of the Faraday cup in each Faraday cup assembly is obtained. 1i and I 2i , to obtain the corresponding parameters of the electron beam, and the inclination angle θ of the electron beam entering each of the Faraday cup assemblies is obtained according to the following formula i , i = 1, 2, 3, ..., N, the unit is rad, the beam spot diameter φ of the electron beam, the beam current I of the electron beam, the divergence angle α of the electron beam, the beam current density J, the angular beam current density J α and beam density distribution J i , d 2 arccos(θi h / d)-θ i h(d 2 -θ i 2 h 2 ) 1 / 2 =πI 2i d / 2(I 1i +I 2i )

[0016]

[0017]

[0018] α=Max(θ i ), i = 1, 2, 3, ..., N

[0019]

[0020]

[0021]

[0022] d is the diameter of the first through hole of the aperture plate;

[0023] D is the inner diameter of the cup;

[0024] h is the distance from the upper plane of the third through hole to the upper plane of the first through hole;

[0025] I 1i is the beam current size of the electron beam in the i-th Faraday cup assembly in the upper Faraday cup;

[0026] I 2i is the beam current size of the electron beam in the i-th Faraday cup assembly in the lower Faraday cup;

[0027] N is the number of Faraday cups;

[0028] p is the center distance between two adjacent cup bodies.

[0029] The technical solution of the present invention has the following advantages:

[0030] 1. The electron beam parameter measurement device provided by the present invention comprises a multilayer board with a micro-device array structure, wherein the micro-device structure distributed in an array on the multilayer board constitutes a Faraday cup assembly, wherein each Faraday cup assembly comprises at least two coaxially arranged Faraday cups, wherein at least two Faraday cups are arranged through, wherein the electron beam is injected into the lower Faraday cup through the upper Faraday cup, and the electron beam current size of each Faraday cup is obtained to obtain the corresponding parameters of the electron beam. The Faraday cup assembly is distributed in an array, which makes it easier to locate the center of the electron beam. Only one Faraday cup assembly needs to be located, and the other Faraday cup assemblies are symmetrically distributed relative to the circumference of the Faraday cup assembly, which is closer to the actual distribution of the electron beam parameters, and makes the measurement result more accurate. The device does not need to be moved to scan the electron beam, and since multiple groups of Faraday cup assemblies are provided, multiple parameters can be obtained simultaneously through a single measurement, and the operation is simple, the measurement speed is fast, and the measurement accuracy is high.

[0031] 2. In the electron beam parameter measuring device provided by the present invention, the apertures of the aperture plate, the first insulating plate and the cup body are different, so that the electron beam is received by different Faraday cups in sequence, thereby obtaining the electron beam current size of each layer of Faraday cup to obtain the corresponding parameters of the electron beam. The entire device has a simple structure and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A top view of the structure of the electron beam parameter measuring device;

[0034] Figure 2 A schematic diagram of the structure of the Faraday cup component array distribution;

[0035] Figure 3 A partial cross-sectional front view of the Faraday cup assembly distributed in an array;

[0036] Figure 4 It is a structural cross-sectional front view of the Faraday cup assembly;

[0037] Figure 5 A cross-sectional elevation view of the structure tested for the electron beam parameter measurement device;

[0038] Figure 6 A cross-sectional front view of the structure of the Faraday cup assembly detecting the first electron beam.

[0039] Description of reference numerals:

[0040] 1- aperture plate; 2- first insulating plate; 3- cup body; 4- second insulating plate;

[0041] 5-lower cup body; 6-third insulating plate; 7-first electron beam; 8-second electron beam;

[0042] 9-third electron beam; 10-Faraday cup assembly; 11-multilayer board;

[0043] θ1 is the tilt angle of the first electron beam;

[0044] d is the diameter of the first through hole of the aperture plate;

[0045] D is the inner diameter of the cup body and the lower cup body;

[0046] h is the distance from the upper plane of the third through hole to the upper plane of the first through hole;

[0047] H is the distance from the upper plane of the bottom of the lower cup body to the upper plane of the third through hole;

[0048] I1 is the beam current size of the first electron beam in the upper Faraday cup;

[0049] I2 is the beam current size of the first electron beam in the lower Faraday cup;

[0050] O i are different positions of the Faraday cup, i = 1, 2, 3, …, N;

[0051] I 1i is the beam current size of the electron beam in the i-th Faraday cup assembly in the upper Faraday cup;

[0052] I 2i is the beam current size of the electron beam in the i-th Faraday cup assembly in the lower Faraday cup;

[0053] θ i is the inclination angle of the electron beam entering the i-th Faraday cup assembly;

[0054] φ is the beam spot diameter of the electron beam in the Faraday cup assembly at different positions;

[0055] I is the beam current size of the electron beam in the Faraday cup assembly at different positions;

[0056] α is the divergence angle of the electron beam in the Faraday cup assembly at different positions;

[0057] J is the beam current density of the electron beam in the Faraday cup assembly at different positions;

[0058] J α is the angular beam current density of the electron beam in the Faraday cup assembly at different positions;

[0059] N is the number of Faraday cups;

[0060] p is the center distance between two adjacent cup bodies. DETAILED DESCRIPTION

[0061] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, 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", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0063] 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 it can be indirectly connected 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.

[0064] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0065] like Figures 1 to 6 The figure shows an electron beam parameter measuring device, which includes a multilayer board 11 with a micro-device array structure. The micro-device structure distributed in an array on the multilayer board 11 constitutes a Faraday cup assembly 10.

[0066] The multilayer board 11 is provided with a plurality of micro-device structures arranged in an array. The micro-device structures are coaxially arranged to form a plurality of Faraday cup assemblies 10, which are vertically placed below the electron beam so that the electron beam can be irradiated into the Faraday cup assemblies 10. Figure 2As shown, the Faraday cup assemblies 10 are distributed in a regular hexagon, that is, the Faraday cup assemblies 10 in two adjacent rows are staggered, each group of Faraday cup assemblies 10 includes two coaxially arranged Faraday cups, the two Faraday cups are arranged through, and the distance between each group of Faraday cup assemblies 10 and the adjacent Faraday cup assemblies 10 is p, and p is generally 100nm-10μm. The electron beam passes through the upper Faraday cup and is injected into the lower Faraday cup. The electron beam current size of each layer of Faraday cup is obtained to obtain the corresponding parameters of the electron beam. The electron beam parameter measuring device is square with a side length of 10mm-50mm and a thickness of 0.5mm-2mm.

[0067] The Faraday cup includes an aperture plate 1, a first insulating plate 2 and a cup body 3 which are sequentially arranged along the irradiation direction of the electron beam. A first through hole is provided at the center of the aperture plate 1 for intercepting the electron beam. A second through hole is provided at the center of the first insulating plate 2 for insulating the aperture plate 1 and the cup body 3. A third through hole is provided at the bottom of the cup body 3 for receiving the electron beam. The inner diameter of the first through hole is the same as that of the third through hole, which is generally 10nm-1μm. The inner diameter of the second through hole is the same as that of the cup body 3 and is larger than that of the first through hole and the third through hole, which is generally 20nm-2μm, so that after a part of the electron beam is received by the upper Faraday cup, the remaining part is received by the lower Faraday cup. The lower Faraday cup includes a lower cup body 5, the inner diameter of which is the same as that of the cup body 3, for receiving the electron beam. The distance from the upper plane of the third through hole to the upper plane of the first through hole is h, which is generally 100nm-10μm, and the distance from the upper plane of the bottom of the lower cup body 5 to the upper plane of the third through hole is H, which is generally 100nm-10μm.

[0068] A second insulating plate 4 and a third insulating plate 6 are also provided on the periphery of the Faraday cup. A fourth through hole is provided at the center of the second insulating plate 4. The fourth through hole has the same inner diameter as the second through hole and the cup body 3 and is used to insulate the cup body 3 from the lower cup body 5. The third insulating plate 6 is located below the lower cup body 5 and is used to insulate the electron beam parameter measuring device and the mounting plane.

[0069] The aperture plate 1 is made of molybdenum or tungsten, the first insulating plate 2, the second insulating plate 4 and the third insulating plate 6 are made of silicon dioxide or silicon nitride, and the cup body 3 and the lower cup body 5 are made of molybdenum, tungsten or copper, all of which are highly conductive and high melting point metal materials.

[0070] A method for measuring electron beam parameters is also provided. Figure 5 As shown, the electron beam is irradiated toward the Faraday cup assembly 10 of the multilayer board 11, so that the electron beam passes through the upper Faraday cup and enters the lower Faraday cup, and the electron beam current size I of each Faraday cup in each Faraday cup assembly 10 is obtained. 1i and I 2i , to obtain the corresponding parameters of the electron beam, such as Figure 6As shown, the first electron beam 7, the second electron beam 8 and the third electron beam 9 can be intercepted to obtain the electron beam current size I of the first electron beam 7. 11 and I 21 , the inclination angle is θ1, and the inclination angle θ of the electron beam entering each Faraday cup assembly 10 is obtained according to the following formula: i , i = 1, 2, 3, ..., N, the unit is rad, the electron beam spot diameter φ, the electron beam current I, the electron beam divergence angle α, the beam current density J, the angular beam current density J α and beam density distribution J i ,

[0071] d 2 arccos(θ i h / d)θ i h(d 2 θ i 2 h 2 ) 1 / 2 =πI 2i d / 2(I 1i |I 2i )

[0072]

[0073]

[0074] α=Max(θ i ), i = 1, 2, 3, ..., N

[0075]

[0076]

[0077]

[0078] d is the diameter of the first through hole of the aperture plate;

[0079] D is the inner diameter of the cup body and the lower cup body;

[0080] h is the distance from the upper plane of the third through hole to the upper plane of the first through hole;

[0081] I 1i is the beam current size of the electron beam in the upper Faraday cup of the i-th Faraday cup assembly;

[0082] I 2i is the beam current size of the electron beam in the i-th Faraday cup assembly in the lower Faraday cup;

[0083] N is the number of Faraday cups;

[0084] p is the center distance between two adjacent cup bodies.

[0085] As an alternative embodiment, the Faraday cup assembly 10 may be a plurality of coaxially arranged Faraday cups.

[0086] As an alternative embodiment, the Faraday cup assemblies 10 may also be distributed in arrays of other shapes.

[0087] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A method for measuring electron beam parameters, characterized in that: The following steps are involved: The electron beam is irradiated vertically toward the Faraday cup assembly (10) of the multilayer board (11), so that the electron beam is sequentially injected into the Faraday cup of the lower layer through the upper layer Faraday cup, and the electron beam current size of each layer of the Faraday cup in each layer of the Faraday cup assembly (10) is obtained. I 1i and I 2i , to obtain the corresponding parameters of the electron beam, and the inclination angle of the electron beam entering each of the Faraday cup assemblies (10) is obtained according to the following formula: θ i , i = 1, 2, 3,…, N, in rad, the electron beam spot diameter , the beam current of the electron beam I、 The divergence angle of the electron beam α , beam density J , angular beam density J α and beam density distribution J i , Max( θ i ), i =1, 2, 3,…, N ， i =1, 2, 3,…, N d is the diameter of the first through hole of the aperture plate; D is the inner diameter of the cup; h is the distance from the upper plane of the third through hole to the upper plane of the first through hole; is the beam current size of the electron beam in the i-th Faraday cup assembly in the upper Faraday cup; is the beam current size of the electron beam in the i-th Faraday cup assembly in the lower Faraday cup; N is the number of Faraday cups; p It is the center distance between two adjacent cup bodies.

2. An electron beam parameter measuring device, characterized in that: The electron beam parameter measurement method according to claim 1 is used for measurement, comprising: A multilayer board (11) with a micro-device array structure is provided with a plurality of Faraday cup assemblies (10) distributed in an array, each of the Faraday cup assemblies (10) comprising at least two coaxially arranged Faraday cups, at least two of the Faraday cups being arranged through-connected, an electron beam is injected into the Faraday cup of a lower layer through the Faraday cup of an upper layer, and the electron beam current size of each layer of the Faraday cup is obtained to obtain corresponding parameters of the electron beam.

3. The electron beam parameter measuring device according to claim 2, characterized in that: The Faraday cup assemblies (10) in two adjacent rows are staggered and arranged, and the spacing between every two Faraday cup assemblies (10) is equal.

4. The electron beam parameter measuring device according to claim 3, characterized in that: The Faraday cup comprises an aperture plate (1), a first insulating plate (2) and a cup body (3) which are sequentially arranged along the irradiation direction of the electron beam, wherein a first through hole is provided at the center of the aperture plate (1), a second through hole is provided at the center of the first insulating plate (2), and a third through hole is provided at the bottom of the cup body (3), wherein the first through hole and the third through hole have the same inner diameter, and the second through hole and the cup body (3) have the same inner diameter and are larger than the first through hole and the third through hole, so that after a part of the electron beam is received by the upper Faraday cup, the remaining part is received by the lower Faraday cup.

5. The electron beam parameter measuring device according to claim 2, characterized in that: It also includes a second insulating plate (4) arranged on the outer periphery of the Faraday cup.

6. The electron beam parameter measuring device according to claim 3, characterized in that: The aperture plate (1) is made of molybdenum or tungsten, the first insulating plate (2) and the second insulating plate (4) are made of silicon dioxide or silicon nitride, and the cup body (3) is made of molybdenum, tungsten or copper.

7. The electron beam parameter measuring device according to any one of claims 4 to 6, characterized in that: The inner diameters of the first through hole and the third through hole are 10 nm-1 μm, and the inner diameters of the second through hole and the cup body (3) are 20 nm-2 μm.

8. The electron beam parameter measuring device according to any one of claims 2 to 6, characterized in that: Each set of the Faraday cup assemblies (10) comprises two coaxially arranged Faraday cups. The measurement is performed using the device, comprising the following steps: The electron beam is irradiated vertically toward the Faraday cup assembly (10) of the multilayer board (11), so that the electron beam is sequentially injected into the Faraday cup of the lower layer through the upper layer of the Faraday cup, and the electron beam current size of each layer of the Faraday cup in each layer of the Faraday cup assembly (10) is obtained to obtain the corresponding parameters of the electron beam.

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