Electron beam detection device and detection method

Abstract

The present invention provides an electron beam detection device, comprising: a porous carbon material layer, the porous carbon material layer having a through hole, the porous carbon material layer being composed of a plurality of carbon material particles, nanometer-level or micrometer-level gaps between the plurality of carbon material particles, and the cross-sectional area of ​​the through hole being less than or equal to the cross-sectional area of ​​the electron beam to be detected; a Faraday cup, the Faraday cup being arranged below the porous carbon material layer, the Faraday cup having an opening, the opening being arranged in communication with the through hole of the carbon nanotube porous layer; and an image display, the image display being electrically connected to the porous carbon material layer, the image display forming images of different colors according to the amount of electric charge generated in the porous carbon material layer, and obtaining the image of the electron beam to be detected according to the color of the image in the image display. The present invention also provides an electron beam detection method.

Description

Technical Field

[0001] The present invention relates to an electron beam detection device and a detection method, and in particular to an electron beam detection device and a detection method using a porous carbon material layer. Background Art

[0002] Electrons are accelerated and their energy is increased by the force in the electric field, and they are gathered into a beam in a vacuum to produce an electron beam. Electron beam technology has been widely used in the fields of forming, manufacturing and refining of high-temperature alloys, welding, surface modification and coating preparation of high-temperature alloys, and will continue to be involved in various fields such as aerospace, national defense and military industry, and nuclear industry. In the existing technology, it is often necessary to detect the shape and radius of the cross section of the electron beam in order to draw an image of the electron beam.

[0003] However, the existing electron beam detection device and detection method have low accuracy and complex structure. Therefore, it is of great significance to provide an electron beam detection device and detection method that is simple to operate and has high accuracy. Summary of the invention

[0004] In view of this, the present invention provides an electron beam detection device and a detection method with a simple structure and high detection accuracy.

[0005] An electron beam detection device, comprising:

[0006] A porous carbon material layer, wherein the porous carbon material layer has a through hole extending through the thickness direction thereof, the cross-sectional area of ​​the through hole is less than or equal to the cross-sectional area of ​​the electron beam to be measured, and the porous carbon material layer is composed of a plurality of carbon material particles, and there are nanometer-level or micrometer-level gaps between the plurality of carbon material particles;

[0007] a Faraday cup, the Faraday cup being disposed below the porous carbon material layer, the Faraday cup having an opening, the opening being connected to the through hole of the carbon nanotube porous layer; and

[0008] An image display is electrically connected to the porous carbon material layer. The image display forms images of different colors according to the amount of charge generated in the porous carbon material layer, and the image of the electron beam to be measured is obtained according to the color of the image in the image display.

[0009] An electron beam detection method comprises the following steps:

[0010] Step S1, providing the electron beam detection device mentioned above;

[0011] Step S2, moving the electron beam to be measured relative to the porous carbon material layer; and

[0012] Step S3, observing the image in the image display, and obtaining the image of the electron beam to be measured according to the color of the image.

[0013] Compared with the prior art, the electron beam detection device provided by the present invention adopts a porous carbon material layer with through holes. When in use, the electron beam to be tested moves relative to the porous carbon material layer. When the electron beam is irradiated on the through hole, the size of the electron beam irradiated on the porous carbon material layer changes, and then the image of the electron beam can be obtained according to the image color on the image display. The structure of the device and the detection method are very simple. Moreover, the electrons in the electron beam to be tested will be refracted and reflected multiple times between the tiny gaps between the multiple carbon material particles in the porous carbon material layer structure, and cannot be emitted from the porous carbon material layer. At this time, the absorption rate of the porous carbon material layer to electrons can reach more than 99.99%, almost 100%, and can be regarded as an absolute black body of electrons. Therefore, when the electron beam is fully irradiated on the porous carbon material layer and not or partially irradiated on the porous carbon material layer, the image color in the image display will be very different, which can be easily distinguished by the naked eye. Therefore, the detection accuracy of the electron beam detection device of the present invention and the detection method using the electron beam detection device is also very high. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic structural diagram of an electron beam detection device provided in the first embodiment of the present invention.

[0015] Figure 2 This is a schematic diagram of the disassembled structure of the electron beam detection device provided in the first embodiment of the present invention.

[0016] Figure 3 When the porous carbon material layer is a super ordered carbon nanotube array, Figure 1 The electron beam detection device shows a curve showing a change in electron absorption rate with the height of the super ordered carbon nanotube array.

[0017] Figure 4 A schematic diagram of the result of directly disposing a porous carbon material layer on the surface of a Faraday cup according to an embodiment of the present invention.

[0018] Figure 5 A morphology diagram of a super ordered carbon nanotube array in an electron beam detection device provided by an embodiment of the present invention

[0019] Figure 6 To adopt Figure 1 The image photograph obtained when the electron beam detection device described in the embodiment detects the electron beam to be tested.

[0020] Figure 7 This is a flow chart of an electron beam detection method provided by the second embodiment of the present invention.

[0021] Main component symbols

[0022] Electron beam detection device 10, 20

[0023] Vacuum chamber 101, 201

[0024] Entrance 1011, 2011

[0025] Carbon nanotube structure 102, 202

[0026] First through hole 1021

[0027] Substrate 103, 203

[0028] The second through hole 1031

[0029] Image display 104, 204

[0030] Faraday Cup 105

[0031] Opening 1051

[0032] Electricity meter 106, 207

[0033] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0034] The electron beam detection device and detection method provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0035] See also Figure 1 and Figure 2 The first embodiment of the present invention provides an electron beam detection device 10. The electron beam detection device 10 includes a porous carbon material layer 102, a substrate 103, an image display 104 and a Faraday cup 105. The image display 104 is electrically connected to the porous carbon material layer 102.

[0036] The porous carbon material layer 102 has a first through hole 1021, and the cross-sectional area of ​​the first through hole 1021 is less than or equal to the cross-sectional area of ​​the electron beam to be measured. The first through hole 1021 runs through the thickness direction of the porous carbon material layer 102. The substrate 103 has a second through hole 1031. The Faraday cup 105 has an opening 1051. The porous carbon material layer 102 is arranged on the surface of the substrate 103, and the first through hole 1021, the second through hole 1031 and the opening 1051 are arranged through. The Faraday cup 105 is arranged under the substrate 103, and is used to collect electrons in the electron beam to be measured that pass through the first through hole 1021, the second through hole 1031 and the opening 1051.

[0037] The porous carbon material layer 102 includes a plurality of carbon material particles, and there are tiny gaps between the plurality of carbon material particles. The gaps between the plurality of carbon material particles are preferably nanometer-scale or micrometer-scale. The micrometer-scale refers to a size less than or equal to 1000 micrometers, and the nanometer-scale refers to a size less than or equal to 1000 nanometers. Further, the micrometer-scale refers to a size less than or equal to 100 micrometers, and the nanometer-scale refers to a size less than or equal to 100 nanometers. Preferably, the gaps between the plurality of carbon material particles in the porous carbon material layer 104 form a plurality of micropores, and the pore size of the micropores is preferably 5 micrometers to 50 micrometers. More preferably, the pore size of the micropores is preferably 5 micrometers to 30 micrometers.

[0038] Preferably, the porous carbon material layer 102 is a pure carbon structure, which means that the porous carbon material layer 102 is only composed of a plurality of carbon material particles without containing other impurities, and the carbon material particles are also pure carbon material particles.

[0039] The carbon material particles include one or both of linear particles and spherical particles. The maximum diameter of the cross section of the linear particles is less than or equal to 1000 microns. The linear particles can be carbon fibers, carbon microwires, carbon nanotubes, etc. The maximum diameter of the spherical particles is less than or equal to 1000 microns. The spherical particles can be carbon nanospheres or carbon microspheres, etc. Preferably, the carbon material particles are carbon nanotubes, and the porous carbon material layer 102 is a carbon nanotube structure, which is a carbon nanotube array or a carbon nanotube network structure.

[0040] When the carbon nanotube structure is a carbon nanotube array, there is a crossing angle between the extension direction of the carbon nanotubes in the carbon nanotube array and the substrate 103, and the crossing angle is greater than 0 degrees and less than or equal to 90 degrees, which is more conducive to the small gaps between the multiple carbon nanotubes in the carbon nanotube array to prevent the electrons in the electron beam from being ejected from the carbon nanotube array, thereby improving the collection rate of the electron beam by the carbon nanotube array, and further improving the detection accuracy of the electron beam. In the present embodiment, the carbon nanotube structure is a super-ordered carbon nanotube array, and the extension direction of the carbon nanotubes in the super-ordered carbon nanotube array is perpendicular to the surface of the substrate 103.

[0041] The extending directions of carbon nanotubes in the super-ordered carbon nanotube array are basically the same. Of course, there are a few randomly arranged carbon nanotubes in the super-ordered carbon nanotube array, and these carbon nanotubes will not significantly affect the overall orientation arrangement of most carbon nanotubes in the super-ordered carbon nanotube array. The super-ordered carbon nanotube array does not contain impurities, such as amorphous carbon or residual catalyst metal particles, etc. The carbon nanotubes in the super-ordered carbon nanotube array are closely contacted with each other through van der Waals forces to form an array. The size, thickness and surface area of ​​the super-ordered carbon nanotube array are not limited, and are limited according to actual needs. The preparation method of the super-ordered carbon nanotube array has been disclosed by many previous cases, for example, can refer to the Chinese patent application CN101239712A disclosed by Feng Chen et al. on August 13, 2008. Of course, the carbon nanotube array is not limited to the super-ordered carbon nanotube array, and can also be other carbon nanotube arrays.

[0042] The mesh formed between the carbon nanotubes in the carbon nanotube network structure is very small, at the micron level. The carbon nanotube network structure can be a carbon nanotube sponge, a carbon nanotube film structure, a carbon nanotube paper, or a network structure formed by weaving or winding a plurality of carbon nanotube lines. Of course, the carbon nanotube network structure is not limited to the carbon nanotube sponge, the carbon nanotube film structure, the carbon nanotube paper, or a network structure formed by weaving or winding a plurality of carbon nanotube lines, and can also be other carbon nanotube network structures.

[0043] The carbon nanotube sponge is a sponge-like carbon nanotube macroscopic body formed by a plurality of carbon nanotubes entangled with each other. The carbon nanotube sponge is a self-supporting porous structure.

[0044] The carbon nanotube wire includes a plurality of carbon nanotubes, and the plurality of carbon nanotubes are connected end to end by van der Waals force to form a macroscopic linear structure. The carbon nanotube wire can be a non-twisted carbon nanotube wire or a twisted carbon nanotube wire. The non-twisted carbon nanotube wire includes a plurality of carbon nanotubes arranged along the length direction of the non-twisted carbon nanotube wire. The twisted carbon nanotube wire is composed of a plurality of carbon nanotubes arranged substantially in parallel and twisted along the axial direction of the twisted carbon nanotube wire. The twisted carbon nanotube wire can be formed by relatively rotating the two ends of the non-twisted carbon nanotube wire. In the process of relatively rotating the two ends of the non-twisted carbon nanotube wire, the carbon nanotubes in the non-twisted carbon nanotube wire will be arranged in a spiral shape along the axial direction of the carbon nanotube wire, and connected end to end by van der Waals force in the extension direction, thereby forming the twisted carbon nanotube wire.

[0045] The carbon nanotube film structure is formed by stacking a plurality of carbon nanotube films together, adjacent carbon nanotube films are bonded by van der Waals forces, and there are tiny gaps between carbon nanotubes in the carbon nanotube film structure. The carbon nanotube film can be a carbon nanotube drawn film, a carbon nanotube flocculated film, or a carbon nanotube rolled film.

[0046] The carbon nanotube film comprises a plurality of carbon nanotubes arranged substantially parallel to each other and substantially parallel to the surface of the carbon nanotube film. Specifically, the carbon nanotube film comprises a plurality of carbon nanotubes connected end to end by van der Waals force and arranged in a preferred orientation substantially in the same direction. The carbon nanotube film can be obtained by directly pulling from a carbon nanotube array and is a self-supporting structure. Since a large number of carbon nanotubes in the carbon nanotube film of the self-supporting structure attract each other by van der Waals force, the carbon nanotube film has a specific shape and forms a self-supporting structure. The thickness of the carbon nanotube film is 0.5 nanometers to 100 micrometers, the width is related to the size of the carbon nanotube array from which the carbon nanotube film is pulled, and the length is not limited. For the structure of the carbon nanotube film and its preparation method, please refer to the Chinese patent application No. CN101239712A filed by Fan Shoushan et al. on February 9, 2007 and published on August 13, 2008. In order to save space, only this is cited, but all technical disclosures of the application should also be regarded as part of the technical disclosure of the present invention. Most of the carbon nanotubes in the carbon nanotube film are connected end to end by van der Waals forces. In one embodiment, the carbon nanotube film structure is formed by stacking and crossing multiple layers of carbon nanotube films, and there is a crossing angle α between the carbon nanotubes in adjacent carbon nanotube films, and the crossing angle α is greater than 0 degrees and less than or equal to 90 degrees. The carbon nanotubes in the multiple carbon nanotube films are interwoven to form a mesh film structure.

[0047] The carbon nanotube flocculated membrane comprises a plurality of carbon nanotubes entangled with each other and evenly distributed. The carbon nanotubes are attracted and entangled with each other by van der Waals forces to form a network structure to form a self-supporting carbon nanotube flocculated membrane. The carbon nanotube flocculated membrane is isotropic. The carbon nanotube flocculated membrane can be obtained by flocculating a carbon nanotube array. For the structure and preparation method of the carbon nanotube flocculated membrane, please refer to the Chinese patent application No. CN101284662A filed by Fan Shoushan et al. on April 13, 2007 and published on October 15, 2008. In order to save space, it is only cited here, but all technical disclosures of the application should also be regarded as part of the technical disclosures of the present invention application.

[0048] The carbon nanotube rolled film includes a plurality of carbon nanotubes arranged in disorder, arranged in a preferred orientation in one direction, or arranged in a plurality of directions, and adjacent carbon nanotubes are bonded by van der Waals forces. The carbon nanotube rolled film can be obtained by using a flat press head to press the carbon nanotube array in a direction perpendicular to the substrate on which the carbon nanotube array grows, in which case the carbon nanotubes in the carbon nanotube rolled film are arranged in disorder and the carbon nanotube rolled film is isotropic; the carbon nanotube rolled film can also be obtained by using a roller-shaped press head to roll the carbon nanotube array in a fixed direction, in which case the carbon nanotubes in the carbon nanotube rolled film are preferentially oriented in the fixed direction; the carbon nanotube rolled film can also be obtained by using a roller-shaped press head to roll the carbon nanotube array in different directions, in which case the carbon nanotubes in the carbon nanotube rolled film are preferentially oriented in different directions. The structure and preparation method of the carbon nanotube rolled film can be found in China Public Patent Application No. CN101314464A filed by Fan Shoushan et al. on June 1, 2007 and published on December 3, 2008. To save space, only this application is cited, but all technical disclosures of the application should also be regarded as part of the technical disclosures of the present application.

[0049] The carbon nanotube paper comprises a plurality of carbon nanotubes extending and arranged in the same direction, and the plurality of carbon nanotubes are connected end to end in the extending direction by van der Waals force, and the plurality of carbon nanotubes are arranged substantially parallel to the surface of the carbon nanotube paper. For the structure and preparation method of the carbon nanotube paper, please refer to the Chinese patent publication No. CN103172044B applied by Fan Shoushan et al. on December 21, 2011 and published on July 1, 2015. In order to save space, it is only cited here, but all technical disclosures of the application should also be regarded as part of the technical disclosures of the present invention application.

[0050] Since the carbon nanotube structure is relatively pure, the specific surface area of ​​the carbon nanotubes in the carbon nanotube structure is relatively large, and the carbon nanotube structure itself has great viscosity, the carbon nanotube structure can be fixed on the surface of the substrate 103 by its own adhesive force. It can be understood that in order to better fix the carbon nanotube structure on the surface of the substrate 103, the carbon nanotube structure can also be fixed on the surface of the substrate 103 by an adhesive. In this embodiment, the carbon nanotube structure is relatively pure, the specific surface area of ​​the carbon nanotubes in the carbon nanotube structure is relatively large, and the carbon nanotube structure is fixed on the surface of the substrate 103 by its own adhesive force.

[0051] Since the higher the energy of the electron beam, the deeper its penetration depth in the porous carbon material layer 102, and vice versa, the shallower the penetration depth. For an electron beam with an energy less than or equal to 20 keV, the thickness range of the porous carbon material layer 102 is preferably 200 microns to 600 microns. Within this thickness range, the electron beam is not easy to penetrate the porous carbon material layer 102, nor is it easy to reflect from the porous carbon material layer 102. Within this range, the porous carbon material layer 102 has a relatively high absorption rate for electrons. More preferably, the thickness of the porous carbon material layer 104 is 300-500 microns. More preferably, the thickness of the porous carbon material layer 102 is 250-400 microns.

[0052] See also Figure 3 , when the porous carbon material layer 102 is a super-ordered carbon nanotube array, the electron beam detection device 10 shows a curve of the electron absorption rate changing with the height of the super-ordered carbon nanotube array. As can be seen from the figure, as the height of the super-ordered carbon nanotube array increases, the electron absorption rate of the electron beam detection device 10 increases. When the height of the super-ordered carbon nanotube array is about 500 microns, the electron absorption rate of the electron beam detection device 10 is above 0.95, which is basically close to 1.0; when the height of the super-ordered carbon nanotube array exceeds about 540 microns, as the height of the super-ordered carbon nanotube array continues to increase, the electron absorption rate of the electron beam detection device 10 is basically unchanged. When the porous carbon material layer 102 is a super-ordered carbon nanotube array, the height of the super-ordered carbon nanotube array is preferably 400-540 microns.

[0053] The substrate 103 is preferably a flat structure. The material of the substrate 103 is an insulating material. For example, glass, plastic, silicon wafer, silicon dioxide wafer, quartz wafer, polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), silicon, silicon with an oxide layer, quartz, etc. The shape and size of the substrate 103 are designed according to actual needs. In this embodiment, the substrate 103 is a rectangular silicon substrate.

[0054] It is understood that the substrate 103 is an optional component and is not required. Figure 4 For example, in one embodiment, the electron beam detection device 10 does not include the substrate 103, the porous carbon material layer 102 is directly disposed on the upper surface of the Faraday cup 105, and the first through hole 1021 in the porous carbon material layer 102 is connected to the opening 1051 of the Faraday cup 105.

[0055] The image display 104 is used to form images of different colors according to the amount of charge generated in the porous carbon material layer 102. The image of the electron beam to be measured can be obtained according to the images of different colors in the image display 104. The model of the image display 104 is selected according to actual needs. In this embodiment, the image display 104 is an LCD display.

[0056] The electron beam detection device 10 may further include an ammeter 106, which includes a first terminal and a second terminal, wherein the first terminal is electrically connected to the porous carbon material layer 102, and the second terminal is grounded. The ammeter 106 is used to test the charge generated in the porous carbon material layer 103 and convert the value to form an electrical signal. The ammeter 104 can be an ammeter or a voltmeter. In this embodiment, the ammeter 106 is an ammeter for testing the current value generated by the charge in the porous carbon material layer 102.

[0057] When the electron beam detection device 10 is in use, the electron beam detection device 10 is placed in a vacuum chamber, and the electron beam to be detected is moved relative to the porous carbon material layer 102 to achieve a two-dimensional scanning of the porous carbon material layer 102 by the electron beam to be detected. The two-dimensional scanning of the porous carbon material layer 102 by the electron beam to be detected can be achieved by moving the electron beam to be detected, and can also be achieved by moving the porous carbon material layer 102, the substrate 103, and the Faraday cup 105. In this embodiment, the electron beam to be detected is moved so that the electron beam to be detected performs a two-dimensional scanning of the porous carbon material layer 102, and the motion trajectory of the electron beam to be detected is a plurality of parallel lines, such as The plurality of parallel lines may be spaced equally or unequally. Of course, the moving direction of the electron beam to be measured is not limited to the plurality of parallel lines in this embodiment, and the moving direction of the electron beam to be measured may be selected according to actual needs, as long as two-dimensional scanning can be achieved. For example, in one embodiment, the moving trajectory of the electron beam to be measured is a snake-shaped In one embodiment, the electron beam to be measured moves along a first direction and a second direction respectively, and the first direction and the second direction intersect. In another embodiment, the electron beam translates along an X line and a Y line respectively, and the X line and the Y line are perpendicular.

[0058] When detecting the electron beam, the electron beam to be tested enters the vacuum chamber, and the electron beam to be tested and the porous carbon material layer 102 are moved relative to each other, so that the electron beam to be tested scans the porous carbon material layer 102. When the entire electron beam to be tested hits the porous carbon material layer 102, the electrons in the electron beam to be tested will be refracted and reflected multiple times in the tiny gaps between the multiple carbon material particles in the structure of the porous carbon material layer 102, and cannot be emitted from the porous carbon material layer. At this time, the absorption rate of the porous carbon material layer to electrons can reach more than 99.99%, almost 100%, and can be regarded as an absolute black body of electrons. Therefore, when the entire electron beam to be tested hits the porous carbon material layer 102, the electrons in the entire electron beam are absorbed by the porous carbon material layer 102, and the charge generated in the porous carbon material layer 102 is the largest. At this time, the image color obtained by the image display 104 is also the darkest. When part of the electron beam to be measured hits the porous carbon material layer 102, and the other part hits the first through hole 1021, part of the electron beam hitting the first through hole 1021 enters the Faraday cup 105 through the second through hole 1031 and the opening 1051. At this time, compared with when the electron beam hits the porous carbon material layer 102 completely, the charge generated in the porous carbon material layer 102 will be reduced, and the color of the image obtained in the image display 104 will also become lighter. Moreover, the more electron beams hit the first through hole 1021, the less charge is generated in the porous carbon material layer 102. Since the cross-sectional area of ​​the first through hole 1021 is less than or equal to the cross-sectional area of ​​the electron beam to be measured, when the first through hole 1021 is completely covered by the electron beam to be measured, the electron beams hitting the porous carbon material layer 102 are the least, and the charge generated in the porous carbon material layer 102 is the least, and the color of the image obtained by the image display 104 is the lightest. Moreover, in the image display, when the electron beam to be tested hits the first through hole 1021 and when the electron beam to be tested hits the porous carbon material layer 102, the color difference in the image display 104 is very obvious and can be easily distinguished by naked eyes. When the electron beam to be tested performs a two-dimensional scan on the porous carbon material layer 102, the size and shape of the electron beam to be tested can be easily obtained according to the color difference in the image display 104.

[0059] In this embodiment, the porous carbon material layer 102 is a super ordered carbon nanotube array. Figure 5 , is a morphology image of the super-ordered carbon nanotube array. In the morphology image, the image with lighter color in the middle is the first through hole 1021 part of the super-ordered carbon nanotube array, and the other images with darker color are the carbon nanotube parts in the super-ordered carbon nanotube array. Figure 5 It can be seen that the size of the first through hole 1021 in this embodiment is approximately 20 microns.

[0060] See also Figure 6, is the morphology of the electron beam spot of the electron beam to be measured obtained when the electron beam detection device 10 in this embodiment detects the electron beam to be measured. In the image obtained by the image display 104, the middle color is lighter, and the other parts are darker, and the two colors are very different, which is very easy to distinguish with the naked eye. Among them, the image with a lighter color in the middle is the image of the electron beam to be measured. It can be seen from the figure that the maximum diameter of the electron beam spot is about more than 300 microns.

[0061] See also Figure 7 The second embodiment of the present invention further provides a method for detecting an electron beam using the electron beam detection device 10, and the method for detecting an electron beam comprises the following steps:

[0062] Step S1, providing the electron beam detection device 10;

[0063] Step S2, moving the electron beam to be measured relative to the porous carbon material layer 102; and

[0064] Step S3, observing the image in the image display 104, and obtaining the image of the electron beam to be measured according to the color of the image.

[0065] In step S1 , the electron beam detection device 10 is the electron beam detection device 10 in the first embodiment, which includes all technical features of the electron beam detection device 10 in the first embodiment, and will not be described in detail herein.

[0066] In step S2, the porous carbon material layer 102, the substrate 103 and the Faraday cup 105 in the electron beam detection device 10 are placed in a vacuum chamber. The electron beam to be measured is moved relative to the porous carbon material layer 102, so as to achieve a two-dimensional scanning of the porous carbon material layer 102 by the electron beam to be measured. The movement of the electron beam to be measured relative to the porous carbon material layer 102 can be achieved by moving the electron beam to be measured, or by moving the porous carbon material layer 102, the substrate 103 and the Faraday cup 105. In this embodiment, the electron beam to be measured is moved so that the electron beam to be measured performs a two-dimensional scanning of the porous carbon material layer 102, and the motion trajectory of the electron beam to be measured is Of course, the moving direction of the electron beam to be measured is not limited to that in this embodiment. The moving direction of the electron beam to be measured can be selected according to actual needs, as long as two-dimensional scanning can be achieved. For example, in one embodiment, the moving trajectory of the electron beam to be measured is a snake-shaped In one embodiment, the electron beam to be measured moves along a first direction and a second direction respectively, and the first direction and the second direction intersect. In another embodiment, the electron beam translates along an X line and a Y line respectively, and the X line and the Y line are perpendicular.

[0067] In step S3, when the entire electron beam to be tested hits the porous carbon material layer 102, the electrons in the entire electron beam are absorbed by the porous carbon material layer 102, and the charge generated in the porous carbon material layer 102 is the largest, and the image color obtained by the image display 104 is also the darkest. When part of the electron beam to be tested hits the porous carbon material layer 102, and the other part hits the first through hole 1021, the part of the electron beam that hits the first through hole 1021 enters the Faraday cup 161 through the second through hole 1031 and the opening 1051. At this time, compared with when the electron beam hits the porous carbon material layer 102 entirely, the charge generated in the porous carbon material layer 102 will be reduced, and the image color obtained in the image display 104 will also become lighter. Moreover, the more electron beams hit the first through hole 1021, the less charge is generated in the porous carbon material layer 102. Since the cross-sectional area of ​​the first through hole 1021 is less than or equal to the cross-sectional area of ​​the electron beam to be measured, when the first through hole 1021 is completely covered by the electron beam to be measured, the electron beams hitting the porous carbon material layer 102 are the least, and at this time, the charge generated in the porous carbon material layer 102 is the least, and the image color obtained by the image display 104 is the lightest. Moreover, in the image display, when the electron beam to be measured hits the first through hole 1021 and when the electron beam to be measured hits the porous carbon material layer 102, the color difference in the image display 104 is very obvious, and it is very easy to distinguish with the naked eye.

[0068] The electron beam detection device provided by the present invention adopts a porous carbon material layer. When in use, the electron beam to be detected moves relative to the porous carbon material layer, so that the size of the electron beam irradiated on the porous carbon material layer changes, and then the image of the electron beam can be obtained according to the image color on the image display. The structure and detection method of the electron beam detection device are very simple. Moreover, since the absorption rate of the porous carbon material layer to electrons can almost reach 100%, it can be called an electron black body. Therefore, when the electron beam is fully irradiated on the porous carbon material layer and when it is not or partially irradiated on the porous carbon material layer, the image color in the image display will be very different, which can be easily distinguished by the naked eye. Therefore, the detection accuracy of the electron beam detection device of the present invention and the detection method using the electron beam detection device is also very high.

[0069] In addition, those skilled in the art may also make other changes within the spirit of the present invention. Of course, these changes made according to the spirit of the present invention should be included in the scope of protection required by the present invention.

Claims

1. An electron beam detection device, comprising: A porous carbon material layer, wherein the porous carbon material layer has a through hole extending through the thickness direction thereof, the cross-sectional area of ​​the through hole is less than or equal to the cross-sectional area of ​​the electron beam to be measured, and the porous carbon material layer is composed of a plurality of carbon material particles, and there are nanometer-level or micrometer-level gaps between the plurality of carbon material particles; a Faraday cup, the Faraday cup being disposed below the porous carbon material layer, the Faraday cup having an opening, the opening being connected to the through hole of the porous carbon material layer; and An image display is electrically connected to the porous carbon material layer. The image display forms images of different colors according to the amount of charge generated in the porous carbon material layer, and the image of the electron beam to be measured is obtained according to the color of the image in the image display.

2. The electron beam detection device as claimed in claim 1, characterized in that The carbon material particles include one or more of carbon nanotubes, carbon fibers, carbon nanowires, carbon microspheres or carbon nanospheres.

3. The electron beam detection device as claimed in claim 1, characterized in that: The porous carbon material layer is a carbon nanotube array or a carbon nanotube network structure.

4. The electron beam detection device as claimed in claim 3, characterized in that The carbon nanotube network structure is a carbon nanotube sponge, a carbon nanotube film structure, a carbon nanotube paper, or a network structure formed by weaving or winding a plurality of carbon nanotube lines together.

5. The electron beam detection device as claimed in claim 1, characterized in that The invention further comprises a substrate having a substrate through hole, the porous carbon material layer is arranged on the surface of the substrate, and the through hole of the porous carbon material layer, the substrate through hole and the opening of the Faraday cup are arranged in a continuous manner.

6. The electron beam detection device as claimed in claim 5, characterized in that The porous carbon material layer is a super-aligned carbon nanotube array, and the extension direction of the carbon nanotubes in the super-aligned carbon nanotube array is perpendicular to the surface of the substrate.

7. The electron beam detection device as claimed in claim 1, characterized in that: The carbon material particle portion outside the through holes in the porous carbon material layer is an electronic black body, and the absorption rate of the carbon material particle portion to electrons reaches more than 99.99%.

8. The electron beam detection device as claimed in claim 1, characterized in that: The invention further comprises an electric meter, which comprises a first terminal and a second terminal, wherein the first terminal is electrically connected to the porous carbon material layer, and the second terminal is grounded.

9. An electron beam detection method comprising the following steps: Step S1, providing an electron beam detection device according to any one of claims 1 to 8; Step S2, moving the electron beam to be measured relative to the porous carbon material layer; as well as Step S3, observing the image in the image display, and obtaining the image of the electron beam to be measured according to the color of the image.

10. The electron beam detection method according to claim 9, characterized in that: In step S2, the electron beam to be measured is moved so that the electron beam to be measured performs a two-dimensional scan on the porous carbon material layer, and the movement trajectory of the electron beam to be measured is a plurality of parallel lines.

Images