Electron source and preparation method thereof

Abstract

The invention relates to the technical field of electron sources, and provides an electron source and a preparation method thereof, and the preparation method comprises the steps: providing a substrate, the substrate comprises a light transmitting layer and an electron excitation layer disposed on the surface of the light transmitting layer, and the material of the electron excitation layer comprises at least one of a zero-dimensional material, a one-dimensional material and a two-dimensional material; forming conductive layers which are arranged side by side at intervals on the electron excitation layer; the substrate with the conducting layer is cut to form a plurality of electron emitters, each electron emitter comprises a light-transmitting layer, an electron excitation layer and a conducting layer, the electron excitation layer and the conducting layer are arranged on the surface of the light-transmitting layer, and the conducting layer in each electron emitter is in contact connection with the electron excitation layer; and connecting one side, provided with the light transmitting layer, of the electron emitter with a laser emitting surface of the optical fiber, and positioning the electron excitation layer on a laser emitting path of the optical fiber to obtain an electron source. Batch preparation of the electron source is realized, and the method is simple and high in efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of electron sources, and in particular to an electron source and a preparation method thereof. Background Art

[0002] An electron source is a device that generates vacuum electrons. Traditional electron sources are mainly divided into thermal emission electron sources, field emission electron sources, and photoemission electron sources according to the excitation method. Thermal emission electron sources mainly use metal materials. When heated to thousands of degrees Celsius, electrons are thermally excited and detach from the surface of the material to form vacuum electrons. Field emission electron sources mainly use metal needle tips. Under the action of a strong electric field applied from the outside, a tip discharge effect is generated. Photoemission electron sources use metal materials as photocathodes and use laser irradiation to excite the photocathode material, thereby generating electrons. However, the laser source in traditional photoemission electron sources uses a spatial optical path, which is not only complex in structure but also occupies a large area. Therefore, traditional photoemission electron sources are difficult to mass-produce. Summary of the Invention

[0003] Based on this, an embodiment of the present application provides an electron source that can be produced in batches and a method for producing the same.

[0004] In a first aspect, the present application provides a method for preparing an electron source, the method comprising:

[0005] Providing a substrate, the substrate comprising a light-transmitting layer and an electron excitation layer disposed on a surface of the light-transmitting layer, wherein a material of the electron excitation layer comprises at least one of a zero-dimensional material, a one-dimensional material, and a two-dimensional material;

[0006] forming conductive layers arranged side by side and spaced apart on the electron excitation layer;

[0007] The substrate having the conductive layer is cut to form a plurality of electron emitters, each of the electron emitters comprising the light-transmitting layer and the electron excitation layer and the conductive layer disposed on the surface of the light-transmitting layer, wherein the conductive layer in each electron emitter is in contact with and connected to the electron excitation layer; and

[0008] The electron source is obtained by connecting the side of the electron emitter having the light-transmitting layer to the laser emitting surface of the optical fiber, and the electron excitation layer is located on the laser emitting path of the optical fiber.

[0009] In some embodiments, the method of cutting the substrate having the conductive layer includes:

[0010] The conductive layer is cut along a length direction of the conductive layer, and the substrate is cut at intervals along a width direction of the conductive layer to form a plurality of electron emitters.

[0011] In some embodiments, the electron emitter and the optical fiber are connected by adhesive connection or mechanical connection.

[0012] In some embodiments, the electron emitter and the optical fiber are connected by mechanical connection. Before connecting the electron emitter and the optical fiber, the method for preparing the electron source further includes:

[0013] A mounting member is provided on a side of the electron emitter having the light-transmitting layer, and the mounting member is used for mechanical connection with the optical fiber.

[0014] Optionally, the mounting member includes a fiber optic flange or a fiber optic ferrule.

[0015] In some embodiments, a plurality of grooves spaced apart and arranged side by side are opened on the electron excitation layer, and a conductive material is filled in the grooves to form the conductive layer.

[0016] Optionally, the method for forming the groove on the electron excitation layer includes:

[0017] Partially removing the electron excitation layer to form a plurality of grooves spaced apart from each other on the electron excitation layer; or,

[0018] After a mask layer having a shape of a plurality of the grooves is provided on the surface of the light-transmitting layer, the electron excitation layer is formed on the surface of the light-transmitting layer, and the grooves are formed after the mask layer is removed.

[0019] Further optionally, the groove runs through the length direction of the electron excitation layer, and the groove is opened at least at two opposite edges of the electron excitation layer.

[0020] In some embodiments, the width of the groove is 1 μm to 5 mm.

[0021] In some embodiments, the distance between two adjacent grooves is 1 μm to 1 cm.

[0022] In some embodiments, the electron emitter is circular in shape; optionally, the electron emitter has a diameter of 1 μm to 1 cm; or,

[0023] The electron emitter is in the shape of a rectangle; optionally, the side length of the electron emitter is 1 μm to 1 cm.

[0024] In some embodiments, the thickness of the electron excitation layer is 0.1 nm to 1 cm.

[0025] In some embodiments, the thickness of the light-transmitting layer is 0.1 nm to 1 cm.

[0026] In some embodiments, the light transmittance of the light-transmitting layer is ≥10%.

[0027] In a second aspect, the present application provides an electron source, comprising:

[0028] An electron emitter, comprising a light-transmitting layer, an electron excitation layer and a conductive layer disposed on a surface of the light-transmitting layer, wherein the conductive layer is in contact with and connected to the electron excitation layer, and the material of the electron excitation layer comprises at least one of a zero-dimensional material, a one-dimensional material, and a two-dimensional material;

[0029] An optical fiber, wherein the laser emitting surface of the optical fiber is connected to the side of the electron emitter having the light-transmitting layer, and the electron excitation layer is located on the laser emitting path of the optical fiber.

[0030] In some embodiments, the electron source further includes a mounting member, which is disposed on a side of the electron emitter having the light-transmitting layer, and is used to connect the electron emitter and the optical fiber.

[0031] Optionally, the mounting member includes a fiber optic flange or a fiber optic ferrule.

[0032] Compared with traditional technologies, this application has at least the following beneficial effects:

[0033] The electron source in this application adopts a combined structure of an electron emitter and an optical fiber. The optical fiber transmits laser light and, as a carrier of the electron emitter, can provide a stable excitation source with adjustable wavelength, polarization, and optical mode. It can be applied to different application scenarios without providing a complex optical path, and has the characteristics of small size and high integration. During the preparation process, electron emitters are prepared in batches using a light-transmitting layer having a large-area electron excitation layer on the surface, wherein a conductive layer is formed on the electron excitation layer, and then a plurality of electron emitters are formed by cutting, and then the electron emitter is integrated with the optical fiber to obtain an electron source. The preparation method of this application is simple, greatly improves the preparation efficiency of the electron source, and realizes the mass production of the electron source. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a top-view process flow chart of a method for preparing an electron source provided in one embodiment of the present application. In the figure, direction A represents the length direction of the conductive layer, direction B represents the width direction of the conductive layer, and the dotted line represents the cutting position;

[0035] Figure 2 This is a cross-sectional process flow chart of a method for preparing an electron source provided in one embodiment of the present application, wherein the dotted line in the figure represents the cutting position;

[0036] Figure 3This is a schematic structural diagram of an electron source provided in one embodiment of the present application.

[0037] Among them, 10 is a substrate; 11 is a light-transmitting layer; 12 is an electron excitation layer; 13 is a conductive layer; 20 is an electron source; 21 is an electron emitter; 22 is an optical fiber; and 23 is a mounting part. DETAILED DESCRIPTION

[0038] Below in conjunction with embodiment and example, the application is further described in detail These embodiment and example are only used to illustrate the application and are not used to limit the scope of the application, and the purpose of providing these embodiment and example is to make the understanding of the disclosure of the application more thorough and comprehensive. It should also be understood that the application can be implemented in many different forms and is not limited to the embodiment and example described herein. Those skilled in the art can make various changes or modifications without violating the connotation of the application, and the equivalent form obtained also falls within the protection scope of the application. In addition, in the description below, a large amount of specific details are given in order to provide a more complete understanding of the application, and it should be understood that the application can be implemented without one or more of these details.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0040] In this application, the terms "optionally," "optional," and "optional" mean optional or dispensable, i.e., they refer to either option being selected from two parallel options: "with" or "without." If a technical solution contains multiple "optional" clauses, each "optional" clause is independent unless otherwise specified and there are no contradictions or constraints.

[0041] In this application, the terms "first" and "second" in "the first aspect" and "the second aspect" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or quantity, nor should they be understood as implicitly indicating the importance or quantity of the technical features indicated. Furthermore, "first" and "second" serve only as non-exhaustive enumeration and description and should be understood not to constitute a closed-ended limitation on quantity.

[0042] In this application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0043] In this application, when referring to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​within the numerical interval is deemed to be continuous and includes the two numerical endpoints of the numerical interval (i.e., the minimum and maximum values), as well as each numerical value between the two numerical endpoints. Unless otherwise specified, when a numerical interval refers only to integers within the numerical interval, it includes the two endpoint integers of the numerical range, as well as each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe a feature or characteristic, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. "Numerical interval" is broadly allowed to include quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.

[0044] All documents mentioned in this application are cited as references in this application, just as each document is cited as reference separately. Unless they conflict with the application purpose and / or technical solution of this application, the cited documents involved in this application are cited in their entirety and for all purposes. When cited documents are involved in this application, the definitions of relevant technical features, terms, nouns, phrases, etc. in the cited documents are also cited. When cited documents are involved in this application, the examples and preferred embodiments of the cited relevant technical features may also be incorporated into this application as references, but are limited to the ability to implement this application. It should be understood that when the cited content conflicts with the description in this application, the present application shall prevail or be adaptively amended according to the description in this application.

[0045] Traditionally, electron sources utilize spatial optical paths, resulting in complex structures that are unsuitable for large-scale batch production. Furthermore, electron emitters are formed through film growth, making the fabrication process for individual electron emitters complex and inefficient.

[0046] In a first aspect, the present application provides a method for preparing an electron source, the method comprising:

[0047] Providing a substrate, the substrate comprising a light-transmitting layer and an electron excitation layer disposed on a surface of the light-transmitting layer, wherein a material of the electron excitation layer comprises at least one of a zero-dimensional material, a one-dimensional material, and a two-dimensional material;

[0048] forming conductive layers arranged side by side and spaced apart on the electron excitation layer;

[0049] The substrate having the conductive layer is cut to form a plurality of electron emitters, each of the electron emitters comprising the light-transmitting layer and the electron excitation layer and the conductive layer disposed on the surface of the light-transmitting layer, wherein the conductive layer in each electron emitter is in contact with and connected to the electron excitation layer; and

[0050] The electron source is obtained by connecting the side of the electron emitter having the light-transmitting layer to the laser emitting surface of the optical fiber, and the electron excitation layer is located on the laser emitting path of the optical fiber.

[0051] The electron source in this application adopts a combined structure of an electron emitter and an optical fiber. The optical fiber transmits laser light and, as a carrier of the electron emitter, can provide a stable excitation source with adjustable wavelength, polarization, and optical mode. It can be applied to different application scenarios without providing a complex optical path, and has the characteristics of small size and high integration. During the preparation process, electron emitters are prepared in batches using a light-transmitting layer having a large-area electron excitation layer on the surface, wherein a conductive layer is formed on the electron excitation layer, and then a plurality of electron emitters are formed by cutting, and then the electron emitter is integrated with the optical fiber to obtain an electron source. The preparation method of this application is simple, greatly improves the preparation efficiency of the electron source, and realizes the mass production of the electron source.

[0052] It is understood that the substrate in the present application can be a light-transmitting layer directly using a material having an electron excitation layer on its surface. For example, the substrate can be a wafer having graphene on its surface, and the wafer can be a circular or square structure of a size of 2 inches, 4 inches, or 8 inches. Graphene is only an example and can also be replaced with other zero-dimensional materials, one-dimensional materials, or two-dimensional materials. Alternatively, the electron excitation layer can be prepared on the surface of the light-transmitting layer. For example, the electron excitation layer can be formed on the light-transmitting layer by deposition or growth.

[0053] It is understandable that the electron excitation layer is arranged on the laser emission path of the optical fiber, and the laser emitted by the optical fiber can directly irradiate the electron emission layer, so that the electron excitation layer is excited by the laser and emits electrons.

[0054] This application uses low-dimensional materials such as zero-dimensional materials, one-dimensional materials, or two-dimensional materials as the material for the electron excitation layer. The low-dimensional materials have atomic-level thickness, and back-incident electrons can be emitted without being transmitted through the body, resulting in high electron emission efficiency. Moreover, low-dimensional materials have no dangling bonds, are stable in nature, have a high melting point, are not easily damaged, and can be used in high-power excitation scenarios, with good stability and a long service life. In addition, low-dimensional materials can be directly integrated with optical fibers, and optical fibers transmit lasers. As a carrier of low-dimensional materials, they can provide a stable excitation source with adjustable wavelength, polarization, and optical mode. They can be applied to different application scenarios without providing a complex optical path, and have the characteristics of small size and high integration.

[0055] It should be noted that in this application, low-dimensional materials refer to zero-dimensional materials, one-dimensional materials, or two-dimensional materials. Zero-dimensional materials typically have discrete energy levels. Under laser excitation, electrons are primarily excited by tunneling from discrete energy levels, which can excite highly monochromatic electrons. The emitted electrons have concentrated energy and low energy dispersion. One-dimensional materials have the characteristics of a small curvature radius (nanometer level), which can enhance the interaction between light and matter and provide a large field enhancement factor, ensuring multiphoton emission, light field emission, etc., and are used in scenarios requiring high-brightness electron sources. Two-dimensional materials have the characteristics of atomic layer thickness. When lasers interact with two-dimensional materials, the transmission mode of light is hardly affected, and the stability is high. Moreover, the excited electrons can be directly emitted without scattering within the material, ensuring the purity of the emitted electron properties and an extremely narrow pulse width.

[0056] In this application, zero-dimensional materials refer to materials whose three spatial dimensions are nanometer-scale, preventing electrons from moving freely. One-dimensional materials refer to materials whose electrons can move freely only in one non-nanoscale direction. Two-dimensional materials refer to materials whose electrons can move freely only in two non-nanoscale dimensions (i.e., in-plane motion). Nanoscale refers to 0.1nm to 100nm. Zero-dimensional, one-dimensional, and two-dimensional materials can be excited to emit electrons under laser excitation.

[0057] In some embodiments, the zero-dimensional material comprises at least one of quantum dots, fullerenes, NV color centers, and nanocrystals, wherein the NV color center refers to a nitrogen vacancy color center, and the quantum dots comprise at least one of carbon quantum dots, CdSe colloidal quantum dots, and GaAs semiconductor quantum dots.

[0058] In some embodiments, the one-dimensional material comprises at least one of nanotubes, nanobelts, and nanowires. Optionally, the nanowires comprise at least one of gold nanowires, semiconductor (GaAs) nanowires, and Te quantum wires; and the nanotubes comprise carbon nanotubes.

[0059] In some embodiments, the two-dimensional material includes at least one of graphene, black phosphorus, a transition metal chalcogenide, and hexagonal boron nitride. Optionally, the transition metal chalcogenide includes at least one of WS2, WSe2, and NbSe2.

[0060] In some embodiments, the method of cutting the substrate having the conductive layer includes:

[0061] The conductive layer is cut along its length, and the substrate is cut at intervals along its width to form a plurality of electron emitters. Optionally, the cutting positions are along the central axis of the conductive layer. This invention cuts the conductive layer along its length, enabling the formation of conductive layers on both sides of the electron excitation layer. Furthermore, by cutting along the width of the conductive layer, similar to a grid-like cutting method, a plurality of electron emitters are formed, enabling the production of electron emitters in large quantities.

[0062] In some embodiments, the substrate can be cut using either laser cutting or mechanical cutting, as long as the cutting method is sufficient to form electron emitters. It is understood that the cutting shape can be preset to form electron emitters of different shapes. For example, the cutting shape can be preset based on the position of the conductive layer and the electron excitation layer to ensure contact and connection between the electron excitation layer and the conductive layer. For example, a grid-like cutting pattern can be used to form square electron emitters; alternatively, a single circular cutting pattern can be used to form multiple circular electron emitters.

[0063] In some embodiments, the electron emitter and the optical fiber are connected by adhesive connection or mechanical connection. Optionally, the adhesive connection can be made by UV curing glue; the mechanical connection can be made by matching with a mounting member.

[0064] In some embodiments, the electron emitter and the optical fiber are connected by mechanical connection. Before connecting the electron emitter and the optical fiber, the method for preparing the electron source further includes:

[0065] A mounting member is provided on the side of the electron emitter having the light-transmitting layer, the mounting member being used for mechanical connection with the optical fiber. Optionally, the mounting member comprises an optical fiber flange or an optical fiber ferrule.

[0066] The present application uses a mounting part to realize the connection between the optical fiber and the electron emitter, thereby realizing a stable connection between the optical fiber and the electron emitter. In addition, by using an optical fiber flange or an optical fiber ferrule, the electron emitter and the optical fiber can be detachably replaced, which has higher adaptability.

[0067] In some embodiments, the conductive layer on the electron excitation layer in the present application can be formed directly on the surface of the electron excitation layer, or a groove can be formed on the electron excitation layer and the conductive layer can be formed in the groove to achieve electronic conduction between the conductive layer and the electron excitation layer.

[0068] It is understandable that the grooves on the electron excitation layer can be formed when the electron excitation layer is formed, or can be formed after the electron excitation layer is formed.

[0069] In some embodiments, a plurality of grooves spaced apart and arranged side by side are formed on the electron excitation layer, and conductive material is filled in the grooves to form the conductive layer.

[0070] Optionally, the method for forming the groove on the electron excitation layer includes:

[0071] Partially removing the electron excitation layer to form a plurality of grooves spaced apart from each other on the electron excitation layer; or,

[0072] After a mask layer having a shape of a plurality of the grooves is provided on the surface of the light-transmitting layer, the electron excitation layer is formed on the surface of the light-transmitting layer, and the grooves are formed after the mask layer is removed.

[0073] It is understood that the electron excitation layer may be removed by etching or other removal methods in the present application, and the conductive layer may be formed by deposition or other formation methods in the present application.

[0074] Optionally, the grooves extend through the length of the electron excitation layer and are formed at at least two opposing edges of the electron excitation layer. The present application provides grooves at the edges of the electron excitation layer and extends along the length of the electron excitation layer, thereby enabling electron emitters with opposing conductive layers to be formed at the edges of the electron excitation layer after cutting, thereby improving substrate utilization and avoiding material waste.

[0075] In some embodiments, the width of the groove is 1 μm to 5 mm, for example, 1 μm, 50 μm, 100 μm, 500 μm, 1 mm, 2 mm, 3 mm, 4 mm or 5 mm.

[0076] In some embodiments, the distance between two adjacent grooves is 1 μm to 1 cm, for example, it can be 1 μm, 100 μm, 500 μm, 1000 μm, 2000 μm, 3000 μm, 4000 μm, 5000 μm, 6000 μm, 7000 μm, 8000 μm, 9000 μm or 1 cm.

[0077] In some embodiments, the electron emitter is circular in shape; optionally, the diameter of the electron emitter is 1 μm~1 cm, for example, it can be 1 μm, 100 μm, 500 μm, 1000 μm, 2000 μm, 3000 μm, 4000 μm, 5000 μm, 6000 μm, 7000 μm, 8000 μm, 9000 μm or 1 cm.

[0078] In some embodiments, the electron emitter is rectangular in shape; optionally, the side length of the electron emitter is 1 μm~1 cm, for example, it can be 1 μm, 100 μm, 500 μm, 1000 μm, 2000 μm, 3000 μm, 4000 μm, 5000 μm, 6000 μm, 7000 μm, 8000 μm, 9000 μm or 1 cm.

[0079] In some embodiments, the thickness of the electron excitation layer is 0.1 nm to 100 nm, for example, 0.1 nm, 0.5 nm, 1 nm, 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm or 100 nm.

[0080] In some embodiments, the thickness of the light-transmitting layer is 0.1 nm to 1 cm, for example, it can be 0.1 nm, 0.5 nm, 1 nm, 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 500 nm, 1 μm, 100 μm, 500 μm, 1000 μm, 2000 μm, 3000 μm, 4000 μm, 5000 μm, 6000 μm, 7000 μm, 8000 μm, 9000 μm or 1 cm.

[0081] In some embodiments, the light transmittance of the light-transmitting layer is ≥10%, for example, it can be 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 100%.

[0082] In some embodiments, the conductive layer is made of a conductive metal. Optionally, the conductive layer is made of at least one of Au, Ag, Ti, and Cr.

[0083] In some embodiments, the optical fiber is a solid core optical fiber, a needle tip optical fiber, or a side-section optical fiber.

[0084] In some embodiments, the optical fiber is a needle-tip optical fiber. In this application, a low-dimensional material is disposed on the needle-tip optical fiber. Due to the needle-tip geometry of the needle-tip optical fiber, the field emission enhancement factor is increased, enabling a higher-brightness electron source. The low-dimensional material can be a two-dimensional material. Furthermore, at least one of a zero-dimensional material and a one-dimensional material can be disposed on the two-dimensional material, thereby achieving functions such as high brightness, low energy dispersion, and narrow pulse width.

[0085] In some embodiments, the optical fiber is a side-section optical fiber. The low-dimensional material of the present application is arranged on the side section of the side-section optical fiber, and the evanescent wave leaked from the core interacts with the low-dimensional material in the horizontal direction. For example, the low-dimensional material adopts a two-dimensional material, and obtains an edge state similar to that of a one-dimensional material at the side section, forming a new electron emission structure, realizing functions such as high brightness, low energy dispersion and narrow pulse width; the low-dimensional material adopts a one-dimensional material, and obtains an edge state of a zero-dimensional material at the side section, forming a new electron emission structure, realizing functions such as high brightness, low energy dispersion and narrow pulse width; the low-dimensional material adopts a combination of two-dimensional material, one-dimensional material and zero-dimensional material, and the energy band of the two-dimensional material can be modulated by doping one-dimensional and zero-dimensional materials, thereby improving the interaction between light and material and realizing electron emission with functions such as high brightness, low energy dispersion and narrow pulse width.

[0086] In some embodiments, the optical fiber is a solid core optical fiber. The low-dimensional material of the present application is arranged at the core of the solid core optical fiber, and the evanescent wave leaked from the core can interact with the low-dimensional material surrounding the optical fiber. Under this system, a longer distance of interaction between light and material can be achieved to achieve high-brightness electron emission. In addition, different diameters of micro-nano optical fibers can be drawn, and light of different modes and intensities can interact with low-dimensional materials to achieve precise control of electron emission parameters. In addition, different types or dimensions of materials can be further grown or transferred on the grown or transferred low-dimensional material to form a heterojunction to achieve multifunctional electron emission.

[0087] It should be noted that this application does not make any specific requirements or special limitations on the size of the optical fiber. Those skilled in the art can reasonably select the size of the optical fiber according to actual usage requirements.

[0088] In conventional technology, when preparing the above-mentioned electron emitter, it is necessary to transfer the electron excitation layer to the end face of the optical fiber. Taking the dry transfer of the electron excitation layer of the graphene material as an example, the graphene needs to be transferred to the PPC film first, and then transferred to the end face of the optical fiber with the assistance of an optical microscope. Moreover, the optical fiber is long and requires a special fixture to be fixed on the transfer platform, and the transfer process is time-consuming. In addition, it is necessary to prefabricate the conductive layer on the optical fiber in advance. This method is complex to assemble and inefficient, and only 2 to 4 optical fiber electron sources can be produced in 1 hour. However, the present application prepares multiple electron emitters with a conductive layer through a large-area substrate, and then directly assembles the electron emitter with the optical fiber, which greatly improves the preparation efficiency. The method is simple, does not require the transfer operation of the electron excitation layer, and does not require the preparation of a conductive layer on the optical fiber. The substrate can also be purchased directly, which can achieve large-scale preparation of electron sources, and more than 500 electron sources can be produced in 1 hour.

[0089] It is understood that for experimental methods whose specific conditions are not specified in this application, priority should be given to the guidance given in this application, and the experimental manuals or conventional conditions in this field can also be followed, the conditions recommended by the manufacturer, or reference can be made to experimental methods known in the art.

[0090] Exemplarily, a method for preparing the electron source is provided, such as Figure 1 and Figure 2 As shown, the following steps are included:

[0091] S1, providing a substrate 10, the substrate 10 comprising a light-transmitting layer 11 and an electron excitation layer 12 disposed on a surface of the light-transmitting layer 11;

[0092] S2, partially removing the electron excitation layer 12 on the substrate 10 to form a plurality of grooves spaced apart from each other on the electron excitation layer 12, and filling the grooves with a conductive material to form a conductive layer 13;

[0093] S3, cutting the substrate to form a plurality of electron emitters 21;

[0094] S4. Connect the electron emitter 21 and the optical fiber 22 to obtain the electron source 20.

[0095] The second aspect of the present application provides an electron source, such as Figure 3 As shown, the electron source 20 includes:

[0096] An electron emitter 21, wherein the electron emitter 21 includes a light-transmitting layer 11 and an electron excitation layer 12 and a conductive layer 13 disposed on a surface of the light-transmitting layer. The conductive layer 13 in each electron emitter 21 is in contact with the electron excitation layer 12, and the material of the electron excitation layer 12 includes at least one of a zero-dimensional material, a one-dimensional material, and a two-dimensional material.

[0097] The optical fiber 22 has a laser emitting surface connected to the side of the electron emitter 21 having the light-transmitting layer 11 , and the electron excitation layer 12 is located on the laser emitting path of the optical fiber 22 .

[0098] In some embodiments, Figure 3 As shown, the electron source 20 further includes a mounting member 23 . The mounting member 23 is disposed on a side of the electron emitter 21 having the light-transmitting layer 11 . The mounting member 23 is used to connect the electron emitter 21 and the optical fiber 22 .

[0099] Optionally, the mounting member includes a fiber optic flange or a fiber optic ferrule.

[0100] In some embodiments, applications of the electron source include at least one of an electron microscope, an electron beam lithography machine, an X-ray tube, a free electron laser, and a display.

[0101] The electron source in this application adopts a combined structure of an electron emitter and an optical fiber. The optical fiber transmits laser light and, as a carrier of the electron emitter, can provide a stable excitation source with adjustable wavelength, polarization, and optical mode. It can be applied to different application scenarios without providing a complex optical path, and has the characteristics of small size and high integration. During the preparation process, electron emitters are prepared in batches using a light-transmitting layer having a large-area electron excitation layer on the surface, wherein the electron excitation layer is provided with a groove and a conductive material is filled in the groove to form a conductive layer, and then a plurality of electron emitters are formed by cutting, and then the electron emitter is integrated with the optical fiber to obtain an electron source. The preparation method of the present application is simple, greatly improves the preparation efficiency of the electron source, and realizes the mass production of the electron source.

[0102] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and such modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for preparing an electron source, characterized in that: The preparation method of the electron source comprises: Providing a substrate, the substrate comprising a light-transmitting layer and an electron excitation layer disposed on a surface of the light-transmitting layer, wherein a material of the electron excitation layer comprises at least one of a zero-dimensional material, a one-dimensional material, and a two-dimensional material; forming conductive layers arranged side by side and spaced apart on the electron excitation layer; The substrate having the conductive layer is cut to form a plurality of electron emitters, each of the electron emitters comprising the light-transmitting layer and the electron excitation layer and the conductive layer disposed on the surface of the light-transmitting layer, wherein the conductive layer in each electron emitter is in contact with and connected to the electron excitation layer; and The electron source is obtained by connecting the side of the electron emitter having the light-transmitting layer to the laser emitting surface of the optical fiber, and the electron excitation layer is located on the laser emitting path of the optical fiber.

2. The method for preparing an electron source according to claim 1, wherein: The method for cutting the substrate having the conductive layer comprises: The conductive layer is cut along a length direction of the conductive layer, and the substrate is cut at intervals along a width direction of the conductive layer to form a plurality of electron emitters.

3. The method for preparing an electron source according to claim 1, wherein: The electron emitter and the optical fiber are connected by adhesive connection or mechanical connection.

4. The method for preparing an electron source according to claim 3, wherein: The electron emitter and the optical fiber are connected by mechanical connection. Before connecting the electron emitter and the optical fiber, the method for preparing the electron source further includes: A mounting member is provided on a side of the electron emitter having the light-transmitting layer, wherein the mounting member is used for mechanical connection with the optical fiber; Optionally, the mounting member includes a fiber optic flange or a fiber optic ferrule.

5. The method for preparing an electron source according to any one of claims 1 to 4, characterized in that: A plurality of grooves are provided on the electron excitation layer and arranged side by side at intervals, and a conductive material is filled in the grooves to form the conductive layer; Optionally, the method for forming the groove on the electron excitation layer includes: Partially removing the electron excitation layer to form a plurality of grooves spaced apart from each other on the electron excitation layer; or, After providing a mask layer having a shape of a plurality of the grooves on the surface of the light-transmitting layer, forming the electron excitation layer on the surface of the light-transmitting layer, and removing the mask layer to form the grooves; Further optionally, the groove runs through the length direction of the electron excitation layer, and the groove is opened at least at two opposite edges of the electron excitation layer.

6. The method for preparing an electron source according to claim 5, wherein: The groove satisfies at least one of the following conditions: (1) The width of the groove is 1 μm to 5 mm; (2) The distance between two adjacent grooves is 1 μm to 1 cm.

7. The method for preparing an electron source according to any one of claims 1 to 4, characterized in that: The electron emitter is circular in shape; optionally, the electron emitter has a diameter of 1 μm to 1 cm; or, The electron emitter is in the shape of a rectangle; optionally, the side length of the electron emitter is 1 μm to 1 cm.

8. The method for preparing an electron source according to any one of claims 1 to 4, characterized in that: The substrate satisfies at least one of the following conditions: (1) The thickness of the electron excitation layer is 0.1 nm to 1 cm; (2) The thickness of the light-transmitting layer is 0.1 nm to 1 cm; (3) The light transmittance of the light-transmitting layer is ≥10%.

9. An electron source, characterized in that The electron source comprises: An electron emitter, comprising a light-transmitting layer, an electron excitation layer and a conductive layer disposed on a surface of the light-transmitting layer, wherein the conductive layer is in contact with and connected to the electron excitation layer, and the material of the electron excitation layer comprises at least one of a zero-dimensional material, a one-dimensional material, and a two-dimensional material; An optical fiber, wherein the laser emitting surface of the optical fiber is connected to the side of the electron emitter having the light-transmitting layer, and the electron excitation layer is located on the laser emitting path of the optical fiber.

10. The electron source according to claim 9, wherein The electron source further includes a mounting member, which is disposed on a side of the electron emitter having the light-transmitting layer, and is used to connect the electron emitter and the optical fiber; Optionally, the mounting member includes a fiber optic flange or a fiber optic ferrule.

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