Micro-channel plate, preparation method therefor and use thereof

Abstract

The present invention provides a micro-channel plate, a preparation method therefor and the use thereof. The micro-channel plate is provided with a plurality of through channels, wherein on the side of an inlet end face of the micro-channel plate, a flared end face of each channel is a hexagonal tapered hole; and in a cross section perpendicular to the axial direction of each channel, the outer edge of the flared end face of the channel is hexagonal, and the inner edge thereof is circular. The present invention provides a micro-channel plate having hexagonal special-shaped flared holes, which micro-channel plate has a micro-hole array presented as hexagonal tapered holes on an end face and cylinders inside; a circular packed array is replaced by a hexagonal close-packed structure, so that the close packing coefficient of a channel array of the micro-channel plate is increased from 0.907 in existing hexagonal arrangements of circular channels to 1 in the hexagonal arrangement of hexagonal channels, and when the channel wall thickness of the channel of the micro-channel plate at the flared end face is greater than or equal to 100 nm, the opening ratio of the micro-channel plate is greater than or equal to 91%. The opening ratio of an input surface of the micro-channel plate is significantly increased, the detection efficiency of the micro-channel plate regarding input signals is improved, and flared tips and tip discharge caused thereby are avoided, such that the micro-channel plate is more suitable for practical application.

Description

A microchannel plate and its preparation method and application Technical Field

[0001] The present invention relates to the field of electronic technology, and in particular to a microchannel plate, a preparation method thereof, and an application thereof. Background Art

[0002] A microchannel plate (MCP) is a glass-based functional material capable of parallel multiplication of charged particle flows distributed in two dimensions. It is composed of millions of hollow glass channels with micron-sized apertures. Each individual hollow glass channel features a secondary electron emission layer and an electron conduction layer. When charged particles enter the channel, they emit secondary electrons in avalanche and amplify weak currents. MCPs offer advantages such as high temporal and spatial resolution, extremely high signal amplification, compact structure, and low noise. They are widely used in low-light-level night vision, high-energy physics detection, precision timing, high-energy particle detection, medical testing, mass spectrometry, and scientific instrumentation.

[0003] Since charged particles can only be effectively multiplied after entering the channels of a microchannel plate, the aperture ratio of the microchannel plate is a very important parameter. The aperture ratio of the microchannel plate determines the detection efficiency of the microchannel plate and, to a certain extent, affects the noise factor of the microchannel plate. The aperture ratio refers to the ratio of the channel opening area in the active region of the microchannel plate to the area of ​​the entire active region. Thinning the channel wall can increase the aperture ratio of the microchannel plate, but excessively thin pore walls will reduce the mechanical strength of the microchannel plate, making it unable to meet the requirements of practical use. Therefore, the aperture ratio of the microchannel plate is usually between 55% and 65%.

[0004] In the prior art, some methods have been used to shape the channel opening on the input surface of a microchannel plate into a funnel shape, i.e., by flaring the end surface of the microchannel plate to achieve an opening ratio of 70% or even 90%. However, achieving an opening ratio of 90% through flaring the end surface of the microchannel plate inevitably results in a flared tip at the end surface of the flared microchannel plate. This flared tip is highly susceptible to tip discharge when used in high-field applications, potentially damaging the microchannel plate or even the instrument, making it unsuitable for practical applications.

[0005] Summary of the Invention

[0006] The main purpose of the present invention is to provide a microchannel plate and its preparation method and application. The technical problem to be solved is how to provide a microchannel plate with a high opening ratio that will not cause tip discharge when used in high field strength application scenarios, thereby being more suitable for practical use.

[0007] The objectives and technical problems solved by the present invention are achieved by the following technical solutions. A microchannel plate according to the present invention is provided with a plurality of through-channels; on the inlet end face of the microchannel plate, the expanded end faces of the channels are hexagonal tapered holes; and, in a cross section perpendicular to the axial direction of the channels, the expanded end faces of the channels are hexagonal in outer edges and circular in inner edges.

[0008] The purpose of the present invention and the solution to its technical problems can be further achieved by adopting the following technical measures.

[0009] In some embodiments, according to the aforementioned microchannel plate, the flare angle of the microchannel plate is 8° to 55°; wherein the flare angle is the angle between the central axis of the aforementioned channel and the conical surface at the opening end of the aforementioned channel.

[0010] In some embodiments, according to the aforementioned microchannel plate, the expansion cone depth of the expansion end surface of the channel is 0.5d to 6d, where d is the aperture of the channel.

[0011] In some embodiments, according to the aforementioned microchannel plate, the opening ratio of the microchannel plate is ≥91%, and the thickness of the channel wall of the expanded end surface of the aforementioned channel is ≥100 nm.

[0012] In some embodiments, according to the aforementioned microchannel plate, a material with a high secondary electron emission coefficient is provided on the flared end face, and the aforementioned material with a high secondary electron emission coefficient is any one of SiO2, MgO, (Ba, Sr)TiO3, RuO2, Al2O3, CsI, CsTe, KBr, ZnO, SrO, Y2O3, B2O3, ZnO, NaCl or diamond film.

[0013] The purpose of the present invention and the technical problem solved are also achieved by adopting the following technical solutions. A method for preparing a microchannel plate according to the present invention comprises the following steps:

[0014] (1) nesting the third leather tube, the second leather tube, and the first leather tube in sequence from the outside to the inside to form a leather composite sleeve; the aforementioned leather composite sleeve is nested with the core rod to form a composite glass rod;

[0015] The core rod is cylindrical, the first leather tube is hexagonal in shape, the second leather tube is hexagonal in shape, and the third leather tube is hexagonal in shape.

[0016] The first leather material glass, the second leather material glass and the third leather material glass have preset etching properties, and the etching rate of the first leather material glass is ≥ the etching rate of the second leather material glass and is greater than the etching rate of the third leather material glass;

[0017] (2) forming the composite glass rod into a blank plate, removing the core glass from the blank plate, and obtaining a microchannel blank plate with channels;

[0018] (3) performing expansion etching on the first end face of the aforementioned microchannel slab, wherein at the expansion end face of each aforementioned channel, the first skin material is completely etched away, the second skin material is partially etched away, and the inner and outer edges of the third skin material are hexagonal, forming a honeycomb structure, so that the expansion end face of the aforementioned channel is a hexagonal cone hole, thereby obtaining an expanded microchannel slab;

[0019] (4) The aforementioned expanded microchannel plate blank is made into a microchannel plate.

[0020] The purpose of the present invention and the solution to its technical problems can be further achieved by adopting the following technical measures.

[0021] In some embodiments, according to the aforementioned preparation method, the pore size of the first leather tube is 2 μm to 50 μm.

[0022] In some embodiments, according to the aforementioned preparation method, the etching rate of the first skin material glass is 25nm / min~100nm / min; the etching rate of the aforementioned second skin material glass is 1nm / min~50nm / min; the etching rate of the aforementioned third skin material glass is 0.01nm / min~25nm / min.

[0023] In some embodiments, according to the aforementioned preparation method, the aforementioned first skin glass, the aforementioned second skin glass and the aforementioned third skin glass are resistant to acid corrosion, and the aforementioned core glass can be corroded by acid; in step (2), the aforementioned core glass is removed by acid corrosion.

[0024] The purpose of the present invention and the technical problems solved therein are also achieved by adopting the following technical solutions: The application of the aforementioned microchannel plate proposed in the present invention in an image intensifier, an ion detector or a detection instrument.

[0025] Through the above technical solution, the microchannel plate of the present invention and its preparation method and application have at least the following advantages:

[0026] The present invention proposes a microchannel plate, whose inlet end face has a hexagonal special-shaped expanded hole with an end face hexagonal cone hole and an inner cylinder. The circular stacking array is replaced by a hexagonal close stacking, so that the close packing coefficient of the channel array of the microchannel plate is increased from π / (2√3) (≈0.907) when the existing circular channels are arranged in a hexagonal manner to 1 when the hexagonal channels are arranged in a hexagonal manner. Under the same channel wall thickness conditions, the opening ratio is increased by more than 10.25%. When the channel wall thickness of the expanded end face of the microchannel plate channel is ≥100nm, the opening ratio of the microchannel plate is ≥91%. The opening ratio of the input surface of the microchannel plate is significantly improved, the detection efficiency of the microchannel plate for the input signal is improved, and the tip discharge caused by the expanded tip is avoided. The application scenarios of the microchannel plate are expanded to fully cover high / medium / low end face field strength application scenarios, greatly improving the practicality of the expanded microchannel plate.

[0027] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic structural diagram of a microchannel plate from a first perspective in some embodiments;

[0029] FIG2 is a schematic structural diagram of a microchannel plate from a second perspective in some embodiments;

[0030] FIG3 is a schematic diagram showing calculation of the microchannel plate opening ratio in some embodiments;

[0031] FIG4 is a schematic diagram of the structure of a composite glass rod in some embodiments;

[0032] FIG5 is a schematic diagram of the structure of a microchannel slab in some embodiments;

[0033] FIG6 is a schematic diagram showing the evolution of the end surface structure of a microchannel slab during the expansion process in some embodiments;

[0034] FIG7 is a schematic diagram of the structure of a flared microchannel slab in some embodiments;

[0035] FIG8 is a schematic structural diagram of a conventional trumpet-shaped flared microchannel plate in Comparative Example 1;

[0036] FIG9 is a schematic structural diagram of a conventional trumpet-shaped large-expansion microchannel plate in Comparative Example 2;

[0037] FIG10 is a schematic diagram showing the calculation of the opening ratio of a conventional trumpet-shaped flared microchannel plate;

[0038] FIG11A is a schematic diagram of a microchannel plate according to the present invention used in an image intensifier;

[0039] FIG11B is a schematic diagram of a microchannel plate of the present invention used in a mass spectrometer;

[0040] FIG11C is a schematic diagram of a microchannel plate according to the present invention used in an enhanced imaging detector;

[0041] Explanation of the accompanying drawings: 100, microchannel plate; 101, microchannel plate blank; 102, microchannel plate blank in the first expansion stage; 103, microchannel plate blank in the second expansion stage; 104, expanded microchannel plate blank; 1, microchannel plate edging; 2, channel; 3, glass skin at the expanded end face; 11, microchannel plate electrode; 11, conductive electrode; 12, high secondary electron emission coefficient material; 3-11, first glass skin; 3-12, second glass skin; 3-13, third glass skin; 2-A, core rod; 3-A composite glass sleeve; 3-B, composite glass rod; 3-C, glass skin at the end face of the microchannel plate blank; 3-21, first glass skin of the microchannel plate blank; 3-2, second glass skin of the microchannel plate blank; 3-23, third glass skin of the microchannel plate blank. 3-1. Projection of the first veneer glass on the flared end face view; 3-2. Projection of the second veneer glass on the flared end face view; 3-3. Projection of the third veneer glass on the flared end face view; 4. Channel aperture; 5. Hexagonal channel width across flats at the flared end face; 6. Channel wall thickness at the flared end face; 7. Channel spacing of the microchannel plate; CA, channel centerline; θ, flaring taper angle; 200, conventional trumpet-shaped flared microchannel plate; 201, conventional trumpet-shaped large-opening flared microchannel plate; 8. veneer glass at the conventional trumpet-shaped flared end face; 8-1. Projection of veneer glass on the flared end face view; 8-2, veneer glass at the conventional trumpet-shaped flared end face; 8-10, veneer glass at the trumpet-shaped flared microchannel plate; 8-11, flared tip at the large-opening trumpet-shaped flared input end face; 9. Circular channel diameter at the conventional trumpet-shaped flared end face; 10. Channel wall thickness at the conventional trumpet-shaped flared end face; 400. Image intensifier; 410. Input light window of image intensifier; 411. Photocathode; 420. Fiber optic panel for image intensifier; 421. Fluorescent screen; 430. Vacuum container; 500. Mass spectrometer; 510. Ionization unit of mass spectrometer; 520. Analysis unit of mass spectrometer; 530. Ion detection unit of mass spectrometer; 531. Anode plate of ion detection unit of mass spectrometer; 600. Enhanced imaging detector; 601. Photocathode for enhanced imaging detector; 610. Light cone for enhanced imaging detector; 611. Fluorescent screen for enhanced imaging detector; 620. Readout sensor for enhanced imaging detector. DETAILED DESCRIPTION

[0042] To further illustrate the technical means and effectiveness of the present invention in achieving its intended objectives, the following, in conjunction with the accompanying drawings and preferred embodiments, describes in detail a microchannel plate, its preparation method, and its specific implementation, structure, features, and effectiveness, as proposed by the present invention. In the following description, different references to "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0043] The present invention provides these embodiments to make the present invention thorough and complete, and to fully express the scope of the present invention to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangement of parts and steps, the composition of materials, numerical expressions and numerical values ​​set forth in these embodiments should be interpreted as merely exemplary, and not as limiting.

[0044] A microchannel plate 100 proposed in an embodiment of the present invention, as shown in Figures 1-2, is provided with multiple through channels 2; on the side of the inlet end face of the aforementioned microchannel plate 100, the flared end face of the aforementioned channel 2 is a hexagonal cone hole; and in a cross section perpendicular to the axial direction of the aforementioned channel 2, the outer edge of the flared end face of the aforementioned channel 2 is hexagonal and the inner edge is circular.

[0045] The present invention replaces a circular array with a hexagonal close-packed arrangement, creating a microchannel plate 100 with hexagonal, irregularly shaped holes and an internal cylindrical microhole array. This increases the close-packing coefficient of the channel array of the microchannel plate 100 from 0.907 for the conventional hexagonal arrangement of circular channels to 1 for the hexagonal arrangement of hexagonal channels. The specific calculation process is described below.

[0046] In the embodiment of the present invention, the through-holes 2 of the microchannel plate 100 are flared in a hexagonal cone-shaped internal cylindrical shape, with the numerous flared channels arranged in a hexagonal close-packed pattern. The opening ratio refers to the ratio of the channel opening area in the active region of the microchannel plate 100 to the area of ​​the entire active region. As shown in Figures 1-3, the method for calculating the opening ratio of the microchannel plate 100 of the present invention is as follows:

[0047] D is the distance between channel 2;

[0048] d1 is the distance across the sides of the hexagonal hole on the expanded end face of the present invention;

[0049] According to the hexagonal close-packed packing principle and the definition of the opening ratio, it can be deduced that the opening ratio OAR1 of the microchannel plate 100 of the present invention is: S11=S12=S13 (Formula 3)

[0050] Right now:

[0051] The wall thickness m of the expanded end face of the microchannel plate 100 of the present invention is: m = D - d1 (Formula 6)

[0052] As can be seen from (Equation 5), the aperture coefficient of the flared end face of the microchannel plate 100 of the present invention is 1. Accordingly, the microchannel plate 100 of the present invention can maintain an aperture ratio of ≥91% while satisfying a flared end face channel wall thickness of ≥100nm. This significantly improves the aperture ratio of the microchannel plate input surface, enhancing the microchannel plate's detection efficiency for input signals while avoiding tip discharge caused by the flared tip. This expands the application scenarios of the microchannel plate to fully cover high, medium, and low end face field strength applications, significantly enhancing the practicality of the flared microchannel plate.

[0053] As shown in FIG8-10, according to the hexagonal circular packing principle and the definition of the opening ratio, it can be deduced that the opening ratio OAR2 of the conventional trumpet-shaped flared microchannel plate 200 and the conventional trumpet-shaped large-opening flared microchannel plate 201 is: S21=S22=S23 (Equation 9)

[0054] Right now:

[0055] The wall thickness of the expanded end channel is f, f = D-d2 (Equation 11)

[0056] To meet detection resolution requirements, the general microchannel plate opening ratio is at least 55% to 65%, and the microchannel plate hole spacing range is 2.50μm to 62.50μm. The preferred microchannel plate hole spacing range is 2.50μm to 18.75μm. To avoid flared tip discharge in high / medium end face field strength scenarios, the channel wall thickness f of the trumpet-shaped flared microchannel plate at the flared end face must be ≥100nm. According to (Equation 10), the trumpet-shaped flared microchannel plate opening ratio is less than 90.5%, and in the preferred microchannel plate, if the channel wall thickness f of the trumpet-shaped flared microchannel plate at the flared end face is ≥100nm, then the trumpet-shaped flared microchannel plate opening ratio is less than 89.8%, which makes it impossible to achieve a channel wall thickness f of ≥100nm at the flared end face and a microchannel plate opening ratio of ≥91%.

[0057] In some embodiments, the flare angle θ of the microchannel plate 100 is between 8° and 55°. The flare angle θ is the angle between the channel axis CA and the conical surface at the channel opening. Too small an angle can easily damage the channel wall, while too large an angle can hinder the effective multiplication of incident particles through collision and reflection. Therefore, the flare angle θ is controlled to be between 8° and 55°.

[0058] In some embodiments, the flared end face of channel 2 has a flared depth of 0.5d to 6d, where d is the aperture of channel 2. The microchannel plate 100 can only achieve electron multiplication under external bias conditions, so conductive electrodes 11 must be plated on both end faces of the microchannel plate 100, as shown in Figure 1. The input electrode depth H of the microchannel plate 100 must be no less than 0.3d, otherwise the electrode plating process is prone to occlusion. When the flared depth h is less than or equal to the input electrode depth H, charged particles entering the microchannel plate will be absorbed by the conductive electrodes covering the inner wall of the channel, preventing effective flaring. Therefore, the flared depth h is greater than 0.3d, and the preferred flared depth h is ≥ 0.5d. Because the microchannel plate 100 etches the channel wall horizontally while etching the channel vertically, a too large flared depth h can easily lead to channel wall cracking. In summary, the preferred flared depth h is in the range of 0.5d to 6d.

[0059] In some embodiments, a high secondary electron emission coefficient material 12 is provided on the flared end surface of the microchannel plate 100. The high secondary electron emission coefficient material 12 is any one of SiO2, MgO, (Ba, Sr) TiO3, RuO2, Al2O3, CsI, CsTe, KBr, ZnO, SrO, Y2O3, B2O3, ZnO, NaCl, or diamond film. Preferably, SiO2, MgO, (Ba, Sr) TiO3, RuO2, Al2O3, NaCl, etc. are suitable for detecting particles such as electrons and ions; CsI, CsTe, KBr, ZnO, SrO, diamond film, Y2O3, B2O3, etc. are suitable for detecting ultraviolet light, X-rays, and radiation. The high secondary electron emission coefficient material 12 is deposited using at least one deposition method selected from the group consisting of atomic layer deposition, electron beam evaporation, chemical vapor deposition, ion beam assisted deposition, thermal evaporation, and laser pulse deposition.

[0060] An embodiment of the present invention provides a method for preparing a microchannel plate, comprising the following steps:

[0061] (1) As shown in FIG4 , the third leather material tube, the second leather material tube, and the first leather material tube are nested in sequence from the outside to the inside to form a leather composite sleeve 3-A; the aforementioned leather composite sleeve 3-A is nested in the core material rod 2-A to form a composite glass rod 3-B;

[0062] The core rod 2-A is cylindrical, the first leather tube is hexagonal in shape, the second leather tube is hexagonal in shape, and the third leather tube is hexagonal in shape.

[0063] The first skin material glass 3-11, the first skin material glass 3-12 and the third skin material glass 3-13 have preset etching properties, and the etching rate of the first skin material glass 3-11 is greater than or equal to the etching rate of the first skin material glass 3-12 and greater than the etching rate of the third skin material glass 3-13;

[0064] (2) The composite glass rod 3-B is made into a blank plate, and the core glass in the blank plate is removed to obtain a microchannel plate blank plate 101 with channels, as shown in FIG5 ;

[0065] (3) The first end face of the aforementioned microchannel slab blank 101 is expanded and etched, as shown in FIG6 . At the expanded end face of each aforementioned channel, the first skin glass 3-11 is completely etched and removed, the first skin glass 3-12 is partially etched and removed, and the inner and outer edges of the third skin glass 3-13 are hexagonal, forming a honeycomb structure, so that the expanded end face of the aforementioned channel is a hexagonal cone hole, thereby obtaining an expanded microchannel slab blank 104, as shown in FIG7 .

[0066] (4) The aforementioned expanded microchannel plate blank 104 is made into a microchannel plate 100 .

[0067] Specifically, in step (1), as shown in Figure 4, the first leather material tube is processed into an inner circular and outer hexagonal shape, the second leather material tube and the third leather material tube are both processed into inner and outer hexagonal shapes, the core material rod 2-A is processed into a cylindrical shape, and the third leather material tube is nested in the second leather material tube and the first leather material tube from the outside to the inside in sequence to form a complete set of leather material composite sleeves 3-A, and the complete set of leather material composite sleeves 3-A is nested in the core material rod 2-A to form a composite glass rod tube 3-B.

[0068] In step (2), the composite glass rod tube 3-B is drawn into a monofilament, the monofilament specifications are arranged into a multifilament rod, and then drawn into a multifilament. After the multifilament specifications are arranged, they are melt-pressed into a blank section. Then, the blank plate is obtained by slicing, chamfering, grinding and polishing. The core glass in the blank plate is removed to form a plurality of through-going circular microporous channels, while the composite skin glass is retained to form the composite channel wall, thereby obtaining a microchannel slab blank plate 101, as shown in FIG5 . In FIG5 , 1 is the microchannel plate edging, 2 is the microporous channel, 3-C is the skin glass of the microchannel slab blank plate 101, 3-21 is the first skin glass 3-11 of the microchannel slab blank plate 101, 3-22 is the first skin glass 3-12 of the microchannel slab blank plate 101, and 3-23 is the third skin glass 3-13 of the microchannel slab blank plate 101.

[0069] In step (3), the expansion etching adopts dry etching, and the dry etching specifically includes at least one of plasma coupled etching, ion beam etching and reactive ion beam etching. Wherein, the first skin material glass 3-11 is easily ion-etched before the reduction treatment, the first skin material glass 3-12 is resistant to ion etching before the reduction treatment, and the third skin material glass 3-13 is resistant to ion etching before the reduction treatment, and before the reduction treatment, the ion etching rate of the first skin material glass 3-11 ≥ the ion etching rate of the first skin material glass 3-12 > the ion etching rate of the third skin material glass 3-13.

[0070] The etching and expanding process is shown in Figure 6. The specific steps are:

[0071] ① The first skin material glass 3-11 is easily removed by ion etching before the reduction treatment, and the ion etching rate range is 25nm / min to 100nm / min. Preferably, the ion etching rate of the first skin material glass 3-11 before the reduction treatment is 35nm / min to 100nm / min. As shown in FIG6 , in the early stage of ion etching expansion (first stage), the first skin material glass 3-11 near the input end face of the microchannel plate is etched first and gradually removed along the axial direction of the micropore. The microchannel plate blank 101 is etched and expanded to form the first stage expanded blank 102;

[0072] ② The etching resistance of the first skin material glass 3-12 before the reduction treatment is higher than that of the first skin material glass 3-11 and lower than that of the third skin material glass 3-13. The first skin material glass 3-12 is not easily removed by ion etching before the reduction treatment. The ion etching rate range is 1 nm / min to 50 nm / min. Preferably, the ion etching rate of the first skin material glass 3-12 before the reduction treatment is 25 nm / min to 50 nm / min. In the middle stage of etching and expanding (the second stage), the first skin material glass 3-11 and the first skin material glass 3-12 near the input end face of the microchannel plate are successively etched and gradually removed along the axial direction of the micropore. The first stage expanded blank plate 102 is further etched and expanded to form the second stage expanded blank plate 103;

[0073] ③ The third skin material has excellent ion etching resistance before reduction treatment. The third skin material is extremely resistant to ion etching before reduction treatment, and its ion etching rate ranges from 0.01nm / min to 25nm / min. Preferably, the ion etching rate of the third skin material glass 3-13 before reduction treatment is 0.01nm / min to 11nm / min. In the late stage of etching and expanding (the third stage), the first skin material 3-11 and the second skin material 3-12 close to the input end face of the microchannel plate are successively etched and gradually removed along the axial direction of the micropore. The third skin material is extremely resistant to ion etching and is not easily removed by etching. Finally, at the most surface opening end face of each through hole, the first skin material is completely etched and removed, the second skin material is almost completely etched and removed, and the inner and outer edges of the third skin material are hexagonal, forming a honeycomb structure; the second stage expanded blank plate 103 is further etched and expanded to finally form the microchannel plate expanded blank plate 104.

[0074] After the flaring etching, the flared microchannel slab 104 is obtained, as shown in Figure 7. Reference numeral 3-1 is the projection of the first frit glass 3-11 on the flared end face; reference numeral 3-2 is the projection of the first frit glass 3-12 on the flared end face; reference numeral 3-3 is the projection of the third frit glass 3-13 on the flared end face; CA is the channel centerline; θ is the flaring cone angle; and h is the flaring cone depth.

[0075] In some embodiments, according to the aforementioned preparation method, the aforementioned first skin material glass 3-11, the aforementioned first skin material glass 3-12 and the aforementioned third skin material glass 3-13 are resistant to acid corrosion, and the aforementioned core material glass can be corroded by acid; in step (2), the aforementioned core material glass is removed by acid corrosion. Specifically, the acid used for corrosion is at least one acid solution of hydrochloric acid, nitric acid, citric acid and sulfuric acid with a concentration of 0.1 mol / L to 3.0 mol / L. After acid corrosion cleaning, the core material glass in the blank plate is removed to form a plurality of through circular microporous channels. The first skin material glass 3-11, the first skin material glass 3-12 and the third skin material glass 3-13 all have good acid resistance, specifically including resistance to hydrochloric acid, nitric acid, citric acid and sulfuric acid corrosion, including resistance to corrosion by a mixture of at least two of hydrochloric acid, nitric acid, citric acid and sulfuric acid. Therefore, even after acid corrosion cleaning, the composite skin material glass can still be retained to form the composite channel wall of the microchannel plate.

[0076] In some embodiments, the pore size of the first material tube is 2 μm to 50 μm. A larger pore size in channel 2 of the microchannel plate 100 results in thicker channel walls and a longer time required for expansion etching. Therefore, directional etching is more suitable for microchannel plates with small pore sizes. More preferably, the pore size of the microchannel plate ranges from 2 μm to 15 μm.

[0077] The embodiment of the present invention further proposes the application of the aforementioned microchannel plate 100 in an image intensifier, an ion detector or a detection instrument, which includes a mass spectrometer, a photoelectron spectrometer, an electron microscope or a photomultiplier tube.

[0078] The present invention will be further described below with reference to specific embodiments, but this should not be construed as limiting the scope of protection of the present invention. Non-essential improvements and adjustments made to the present invention by those skilled in the art based on the above-mentioned contents of the present invention still fall within the scope of protection of the present invention.

[0079] Unless otherwise specified, the materials and reagents mentioned below are commercially available products familiar to those skilled in the art. Unless otherwise specified, the methods described are all well-known methods in the art. Unless otherwise defined, technical or scientific terms used shall have the same meanings as those commonly understood by those skilled in the art.

[0080] Example 1

[0081] This embodiment provides a microchannel plate and a method for preparing the same. The specific steps are as follows:

[0082] (1) According to the size design, a first leather tube with an inner circle and an outer hexagonal shape, a second leather tube with an inner and outer hexagonal shape, and a third leather tube with an inner and outer hexagonal shape, as well as a cylindrical core rod 2-A, are prepared. The third leather tube, the second leather tube, and the first leather tube are nested in sequence from the outside to the inside to form a leather composite sleeve 3-A; the leather composite sleeve 3-A is nested with the core rod 2-A to form a composite glass rod 3-B; wherein the etching rate of the first leather glass 3-11 is ≥ the etching rate of the aforementioned first leather glass 3-12 and is greater than the etching rate of the aforementioned third leather glass 3-13; and the leather glass is resistant to acid corrosion, while the core glass is easily corroded by acid.

[0083] (2) The composite glass rod 3-B is drawn into monofilaments and multifilaments, and the multifilaments are arranged into specifications and melt-pressed into blank segments. Then, the blank is sliced, chamfered, ground and polished to obtain a blank plate. After acid etching, the core glass in the blank is removed to form multiple through-going circular microporous channels, while the composite skin glass is retained to form the composite channel walls. Thus, the blank plate forms a microchannel plate blank 101 as shown in FIG5 .

[0084] (3) The first end face of the microchannel plate blank 101 is expanded and etched, and the etching process is shown in Figure 6. At each expanded end face, the first skin glass 3-11 is completely etched and removed, the first skin glass 3-12 is partially etched and removed, and the inner and outer edges of the third skin glass 3-13 are hexagonal, forming a honeycomb structure, so that the expanded end face of the aforementioned channel is a hexagonal cone hole, and an expanded microchannel plate blank 104 is obtained, as shown in Figure 7; in this embodiment, the expansion cone angle θ of the microchannel plate expanded blank 104 is 20°.

[0085] (4) After the expanded blank 104 of the microchannel plate is plated with a metal electrode, as shown in FIG1-2, a high secondary electron emission coefficient material 12 is deposited on the expanded end face to cover the end face of the third skin glass 3-13. The end face coincides with the inlet end face of the hexagonal pyramidal hole formed after etching the first skin glass 3-11 and the second skin glass 3-12, and a portion of the hexagonal pyramidal surface is in the first skin glass 3-11 and the second skin glass 3-12, thereby obtaining a microchannel plate 100.

[0086] The characteristic parameters and tip discharge risk characteristics of Examples 1-1 to 15 of the microchannel plates 100 of various sizes prepared in Example 1 are shown in Table 1.

[0087] Comparative Example 1

[0088] This comparative example provides a conventional trumpet-shaped flared microchannel plate 200, as shown in FIG8 , which adopts a single-layer or composite channel wall structure, specifically comprising: a skin material tube with an inner circular hole and an outer cylindrical shape, a core material rod with a cylindrical shape, and a core material rod with a skin material tube outer covering to form a glass rod-tube structure; then, through single-filament or multi-filament drawing, melting and pressing, slicing, chamfering, grinding and polishing, a blank plate is produced; after acid etching, the core glass in the blank plate is removed to form a plurality of through-going circular microporous channels; then, after wet etching (HF acid etching) or dry etching (one or at least two of plasma coupled etching, ion beam etching, and reactive ion beam etching), the trumpet-shaped flared microchannel plate 200 is formed. Among them, 8 is the skin glass of the conventional trumpet-shaped flared end face; 8-1 is the projection of the skin glass on the flared end face view; 8-2 is the skin glass of the conventional trumpet-shaped flared end face; 8-10 is the skin glass of the trumpet-shaped flared microchannel plate; CA is the channel center axis, and θ is the flared cone angle.

[0089] Comparative Example 2

[0090] This comparative example provides a conventional trumpet-shaped, large-opening flared microchannel plate 201. Based on Comparative Example 1, further etching is performed by wet etching (HF acid etching) or dry etching (one or at least two of plasma-coupled etching, ion beam etching, and reactive ion beam etching), and then further etching or etching is performed to remove the skin glass in a trumpet-shaped flared manner to achieve an opening ratio of ≥ 90%, as shown in FIG9 . Reference numerals 8-11 denote the flared tip of the large-opening trumpet-shaped flared input end face.

[0091] Table 2 shows the characteristic parameters and tip discharge risk characteristics of the conventional trumpet-shaped flared microchannel plates 200 and conventional trumpet-shaped large-opening flared microchannel plates 201 of various sizes prepared in Comparative Examples 1 and 2.

[0092] As shown in Tables 1 and 2, the microchannel plate 100 of the present invention maintains an opening ratio of ≥91% while meeting a requirement for a flared end face channel wall thickness of ≥100 nm. This significantly improves the opening ratio of the microchannel plate's input surface, enhancing the plate's detection efficiency for input signals while also preventing tip discharge caused by the flared tip. This expands the application scope of the microchannel plate to encompass high, medium, and low end face field strength applications, significantly enhancing the practicality of the flared microchannel plate.

[0093] Table 1 Main characteristic parameters and tip discharge risk characteristics of the embodiment

[0094] Table 2 Main characteristic parameters and tip discharge risk characteristics of comparative examples

[0095] Example 2:

[0096] This embodiment relates to the application of the microchannel plate 100 of the present invention, and an image intensifier using the flared microchannel plate of the present invention as a signal multiplication material. As shown in FIG11A , the image intensifier 400 is provided with a vacuum container 430. An input light window 410 is provided at the input end of the vacuum container 430, and a fiber optic panel 420 is provided at the other end of the vacuum container 430. The microchannel plate 100 of the present invention is located between the input light window 410 and the fiber optic panel 420. A photocathode 411 is provided on the inner surface of the input light window 410 (located inside the vacuum container 430), which converts light into electrons. A fluorescent screen 421 is provided on the inner surface of the fiber optic panel 420 (located inside the vacuum container 430). Preferably, the image intensifier 400 is designed so that the microchannel plate 100 of the present invention is positioned near the fluorescent screen 421. This facilitates the full conversion of the multiplied electrons emitted by the microchannel plate 100 of the present invention into optical signals, thereby obtaining a high-resolution image.

[0097] Example 3:

[0098] The present embodiment relates to the application of the flared microchannel plate of the present invention, and a mass spectrometer using the flared microchannel plate of the present invention as a signal detector. As shown in Figure 11B, the mass spectrometer 500 is composed of an ionization unit 510 (for ionizing a sample), an analysis unit 520 (for separating the ionized sample according to the charge-to-mass ratio), and an ion detection unit 530 (for detecting ions passing through the analysis unit 520). The ion detection unit 530 is provided with the microchannel plate 100 of the present embodiment and an anode plate 531. The microchannel plate 100 of the present embodiment can respond to incident ions and emit secondary electrons, and acts as an electron multiplying material. The anode plate 531 serves to collect the secondary electrons emitted by the microchannel plate.

[0099] Example 4:

[0100] This embodiment relates to the application of the flared microchannel plate of the present invention, and an enhanced imaging detector using the flared microchannel plate of the present invention as a signal multiplication material. As shown in FIG11C , the input end of the enhanced imaging detector 600 is provided with the microchannel plate 100 of the present invention, and a photocathode 601 (for converting rays or light signals into electrons) is provided on the input end surface of the microchannel plate 100 of the present invention. A light cone 610 is provided at the other end of the enhanced imaging detector 600, and a fluorescent screen 611 is provided on the large end surface of the light cone 610. Preferably, a readout sensor 620 is coupled to the small end surface of the light cone 610. The readout sensor 620 is a CCD or CMOS, which is conducive to fully converting the multiplied electrons emitted by the microchannel plate 100 of the present invention into light signals and then realizing enhanced high-resolution imaging detection through the small-sized readout sensor 620.

[0101] The technical features in the claims and / or the specification of the present invention may be combined, and the manner of combination is not limited to the combination obtained by reference in the claims. The technical solutions obtained by combining the technical features in the claims and / or the specification are also within the scope of protection of the present invention.

[0102] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiment based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A microchannel plate, characterized in that: A plurality of through channels are provided; on one side of the inlet end face of the microchannel plate, the expanded end face of the channel is a hexagonal cone hole; and, in a cross section perpendicular to the axial direction of the channel, the expanded end face of the channel has a hexagonal outer edge and a circular inner edge.

2. The microchannel plate according to claim 1, characterized in that: The expansion cone angle of the microchannel plate is 8° to 55°; wherein the expansion cone angle is the angle between the central axis of the channel and the cone surface located at the opening end of the channel.

3. The microchannel plate according to claim 1, characterized in that: The expansion cone depth of the expansion end surface of the channel is 0.5d to 6d, and d is the aperture of the channel.

4. The microchannel plate according to claim 1, characterized in that: The opening ratio of the microchannel plate is ≥91%, and the thickness of the channel wall of the expanded end surface of the channel is ≥100 nm.

5. The microchannel plate according to claim 1, characterized in that: A material with a high secondary electron emission coefficient is provided on the expanded end face, and the material with a high secondary electron emission coefficient is any one of SiO2, MgO, (Ba, Sr)TiO3, RuO2, Al2O3, CsI, CsTe, KBr, ZnO, SrO, Y2O3, B2O3, ZnO, NaCl or diamond film.

6. A method for preparing a microchannel plate, characterized in that: The following steps are involved: (1) nesting the third leather material tube, the second leather material tube and the first leather material tube in sequence from the outside to the inside to form a leather material composite sleeve; the leather material composite sleeve is nested with the core material rod to form a composite glass rod; The core material rod is cylindrical, the first leather material tube is in the shape of an inner circle and an outer hexagon, the second leather material tube is in the shape of an inner and outer hexagon, and the third leather material tube is in the shape of an inner and outer hexagon; The first leather glass, the second leather glass and the third leather glass have preset etching properties, and the etching rate of the first leather glass ≥ the etching rate of the second leather glass > the etching rate of the third leather glass; (2) forming the composite glass rod into a blank plate, removing the core glass in the blank plate, and obtaining a microchannel plate blank plate with channels; (3) The first end face of the microchannel plate blank is expanded and etched. At the expanded end face of each channel, the first skin glass is completely etched away, the second skin glass is partially etched away, and the inner and outer edges of the third skin glass are hexagonal to form a honeycomb structure, so that the channel The expanded end surface is a hexagonal cone hole, and the expanded microchannel slab blank is obtained; (4) The expanded microchannel plate blank is made into a microchannel plate.

7. The preparation method according to claim 6, characterized in that: The pore size of the first leather tube is 2 μm to 50 μm.

8. The preparation method according to claim 6, characterized in that: The etching rate of the first skin material glass is 25nm / min to 100nm / min; the etching rate of the second skin material glass is 1nm / min to 50nm / min; and the etching rate of the third skin material glass is 0.01nm / min to 25nm / min.

9. The preparation method according to claim 6, characterized in that: The first skin glass, the second skin glass and the third skin glass are resistant to acid corrosion, and the core glass can be corroded by acid; in step (2), the core glass is removed by acid corrosion.

10. Use of the microchannel plate according to any one of claims 1 to 5 in an image intensifier, an ion detector or a detection instrument.

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