Flange type microchannel plate detector applied to ultrahigh vacuum environment and preparation method thereof

Abstract

The application relates to the technical field of micro-channel plate, and provides a flange type micro-channel plate detector applied to an ultrahigh vacuum environment and a preparation method thereof. The flange type micro-channel plate detector applied to the ultrahigh vacuum environment comprises a shielding cylinder, an upper cover plate, a grid electrode, a grid, a middle ring, a micro-channel plate input electrode, a first-stage micro-channel plate, a second-stage micro-channel plate, a micro-channel plate output electrode, an anode, an anode output capacitor, an isolation sleeve, a lower cover plate, a bottom plate, a supporting sleeve, a flange and a circuit protection module. The flange type micro-channel plate detector applied to the ultrahigh vacuum environment has the advantages of small air release amount, detachability and easy maintenance while ensuring high gain and time response characteristics, and can be used for a long time under a 1*10 ‑7 Pa vacuum environment, and realizes positive / negative electron, positive / negative ion, neutral atom, ultraviolet light, soft X-ray and other detection applications.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microchannel plate, in particular to a flange type microchannel plate detector applied to an ultrahigh vacuum environment and a preparation method thereof. BACKGROUND

[0002] The microchannel plate (MCP) is a two-dimensional electron multiplication array composed of millions of microchannel electron multipliers, and is an element for multiplying an electron stream distributed in two dimensions multiple times. The microchannel plate detector made of the microchannel plate as a core element can realize direct detection of various particles and radiation, and has wide application in the fields of analysis instruments, scientific research devices and space exploration.

[0003] The traditional microchannel plate detector adopts an electrode sheet / electrode column as an electrode interface and a through hole as a mechanical interface, and a user needs to install the microchannel plate detector in a vacuum system by himself / herself and also needs to consider how to apply a power supply on the electrode interface, which is extremely inconvenient to use. In addition, the traditional microchannel plate detector adopts polyimide, polyether ether ketone, epoxy glass cloth plate and other materials, and has a large outgassing amount in an ultrahigh vacuum environment, and the general working environment pressure can only be maintained at 1x10 -4 Pa, which cannot meet the demand for long-term normal use in an ultrahigh vacuum environment of 1x10 -7 Pa. SUMMARY

[0004] The present application aims to provide a flange type microchannel plate detector which can be applied to an ultrahigh vacuum environment and has the advantage of small outgassing amount, and can be used for a long time in a vacuum environment of 1x10 -7 Pa to detect positive / negative electrons, positive / negative ions, neutral atoms, ultraviolet light, soft X-rays and other substances, and directly dock with a vacuum device by using a flange during use, which is convenient to operate.

[0005] According to a first aspect of the present application, a flange type microchannel plate detector applied to an ultrahigh vacuum environment is provided, which comprises a shielding cylinder, an upper cover plate, a grid electrode, a grid, an intermediate ring, a microchannel plate input electrode, a first-stage microchannel plate, a second-stage microchannel plate, a microchannel plate output electrode, an anode, an anode output capacitor, an isolation sleeve, a lower cover plate, a bottom plate, a support sleeve, a flange and a circuit protection module, wherein:

[0006] The SHV joint and the SMA joint are welded on the flange, the SHV joint is an electrode lead-out interface, and the SMA joint is a signal lead-out interface;

[0007] The lower cover plate is pressed on the bottom plate, and the isolation sleeve is coaxially placed with the peripheral hole of the lower cover plate;

[0008] The anode, the microchannel plate output electrode, the second-stage microchannel plate, the first-stage microchannel plate, the microchannel plate input electrode, the intermediate ring, the grid, the grid electrode and the upper cover plate are coaxially stacked on the lower cover plate in sequence, a connecting screw is screwed on the corresponding threaded hole of the bottom plate through the corresponding through holes of the upper cover plate and the isolation sleeve, and the microchannel plate assembly is formed.

[0009] The supporting screw is screwed on the corresponding threaded hole of the flange through the through hole of the bottom plate and the through hole of the supporting sleeve, and the connection between the microchannel plate assembly and the flange is realized.

[0010] The shielding cylinder is located on the upper cover plate, and the assembly shielding is realized by screwing the assembly screw on the corresponding threaded hole of the bottom plate through the through hole of the shielding cylinder.

[0011] The protruding cylinder at the central axis position of the anode is connected with the SMA joint of the flange after passing through the output capacitor of the anode.

[0012] The electrode column of the grid electrode, the electrode column of the microchannel plate input electrode, the electrode column of the microchannel plate output electrode and the electrode column of the anode are all led out from the side and connected with the SHV joint of the flange.

[0013] The circuit protection module is connected with the SMA joint of the flange.

[0014] According to the second aspect of the object of the application, a preparation method of a flange type microchannel plate detector applied to an ultrahigh vacuum environment is also provided, and the method comprises the following steps:

[0015] The lower cover plate is placed on the bottom plate, and the isolation sleeve is coaxially placed with the peripheral hole of the lower cover plate.

[0016] The anode, the microchannel plate output electrode, the second-stage microchannel plate, the first-stage microchannel plate, the microchannel plate input electrode, the intermediate ring, the grid, the grid electrode, the upper cover plate are coaxially stacked on the lower cover plate in sequence, a connecting screw is screwed on the corresponding threaded hole of the bottom plate through the corresponding through holes of the upper cover plate and the isolation sleeve, and the microchannel plate assembly is formed.

[0017] One end of the capacitor is connected with the protruding cylinder of the anode, and the other end is connected with the SMA joint of the flange.

[0018] The supporting screw is screwed on the corresponding threaded hole of the flange through the through hole of the bottom plate and the through hole of the supporting sleeve, and the connection between the microchannel plate assembly and the flange is realized.

[0019] The electrode column of the grid electrode, the electrode column of the microchannel plate input electrode, the electrode column of the microchannel plate output electrode and the electrode column of the anode are respectively connected with the corresponding SHV joint of the flange.

[0020] Put the shielding cylinder on the upper cover plate, pass the assembly screw through the through hole of the shielding cylinder, and screw it on the corresponding threaded hole of the bottom plate.

[0021] The circuit protection module is connected with the SMA joint of the flange.

[0022] Therefore, the assembly of the micro-channel plate type detector with low outgassing amount and high vacuum environment adaptability is realized, the micro-channel plate detector is directly connected with other vacuum equipment through the flange, and the user can conveniently apply a voltage signal. Meanwhile, the four SHV joints and the SMA joint directly welded on the flange do not need sealing rings and other parts, effectively reducing the outgassing amount during use. The materials of the parts working in the vacuum environment are mainly composed of metal, ceramic and lead silicate glass, reducing the outgassing amount.

[0023] It should be understood that all combinations of the aforementioned concepts and additional concepts described in greater detail below can be seen as part of the subject matter of the present disclosure as long as such concepts are not mutually inconsistent. In addition, all combinations of the claimed subject matter are considered as part of the subject matter of the present disclosure.

[0024] The foregoing and other aspects, embodiments and features of the present teachings can be better understood from the following description of the present teachings taken in conjunction with the accompanying drawings. Other aspects, embodiments and features of the present teachings will be apparent from the description that follows and from the claims. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical, or nearly identical, component that is illustrated in various figures is represented with a like numeral. For purposes of clarity, not every component is called out in every drawing. Embodiments of various aspects of the present teachings will now be described, by way of example, with reference to the drawings, in which:

[0026] Figure 1 is an assembly schematic diagram of a flange type micro-channel plate detector applied to an ultrahigh vacuum environment according to an example of the present disclosure.

[0027] Figure 2 is a schematic diagram of a flange according to an example of the present disclosure.

[0028] Figure 3 is a schematic diagram of a grid electrode, a micro-channel plate input electrode, a micro-channel plate output electrode and an anode according to an example of the present disclosure.

[0029] Figure 4 is a general assembly schematic diagram of a flange type micro-channel plate detector according to an example of the present disclosure.

[0030] Figure 5The gas emission amount test result of the microchannel plate detector of the present application example after 4h pumping.

[0031] Figure 6 The electrical schematic diagram of the microchannel plate detector of the present application example.

[0032] Figure 7 The waveform chart of the microchannel plate detector of the present application example.

[0033] The reference signs are defined as follows:

[0034] 1-assembly screw; 2-shield cylinder; 3-connection screw; 4-upper cover plate; 5-grid electrode; 6-grid; 7-intermediate ring; 8-microchannel plate input electrode; 9-first stage microchannel plate; 10-second stage microchannel plate; 11-microchannel plate output electrode; 12-anode; 13-anode output capacitor; 14-isolation sleeve; 15-lower cover plate; 16-support screw; 17-bottom plate; 18-support sleeve; 19-flange; 20-circuit protection module; 21-gap between the shield cylinder and the flange;

[0035] 2a-middle through region of the shield cylinder; 5a-electrode column of the grid electrode; 8a-electrode column of the microchannel plate input electrode; 11a-electrode column of the microchannel plate output electrode; 11b-surface of the microchannel plate output electrode in contact with the second stage microchannel plate;

[0036] 12a-electrode column of the anode; 12b-protruding cylinder in the anode;

[0037] 19a-SHV joint; 19b-SMA joint;

[0038] 20a-high voltage isolation capacitor; 20b-protection circuit diode. DETAILED DESCRIPTION

[0039] In order to have a better understanding of the technical content of the present application, specific embodiments are described below with reference to the accompanying drawings.

[0040] Aspects of the present application are described in the disclosure by reference to the accompanying drawings, in which a number of illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to include all aspects of the present application. It should be understood that a variety of concepts and embodiments as described above, and as described in more detail below, can be implemented in any of numerous ways, as the disclosed concepts and embodiments are not limited to any particular manner of implementation. Also, it is contemplated that some aspects of the present application can be provided and utilized separately.

[0041] {Example 1}

[0042] The flange type micro-channel plate detector applied to the ultra-high vacuum environment according to the embodiment of the application has the advantages of small air leakage, detachability and easy maintenance while ensuring high gain and time response characteristics, and can be used in 1*10 -7 Pa vacuum environment for a long time, and realizes positive / negative electron, positive / negative ion, neutral atom, ultraviolet light, soft X-ray and other detection applications.

[0043] As shown in Figures 1-4 and Figure 6 , the flange type micro-channel plate detector as an example comprises a shielding cylinder 2, an upper cover plate 4, a grid electrode 5, a grid 6, an intermediate ring 7, a micro-channel plate input electrode 8, a first-stage micro-channel plate 9, a second-stage micro-channel plate 10, a micro-channel plate output electrode 11, an anode 12, an anode output capacitor 13, an isolation sleeve 14, a lower cover plate 15, a bottom plate 17, a support sleeve 18, a flange 19, and a circuit protection module 20.

[0044] As shown in Figure 2 , four SHV joints 19a and one SMA joint 19b are welded on the flange 19, the SHV joint 19a is an electrode lead-out interface, and the SMA joint 19b is a signal lead-out interface.

[0045] As a preferred mode, the SHV joint 19a and the SMA joint 19b both penetrate the flange 19 and extend to the outside of the flange 19, and are directly welded, avoiding the use of other parts such as a sealing ring and effectively reducing the air leakage amount when the detector is used.

[0046] The flange type micro-channel plate detector of the embodiment of the application is directly connected to other vacuum equipment by the flange 19, and is convenient to use. The SHV joint extending to the outside of the flange is convenient for users to apply a voltage signal.

[0047] The lower cover plate 15 is pressed on the bottom plate 17, and the isolation sleeve 14 is coaxially placed with the peripheral hole of the lower cover plate 15.

[0048] The lower cover plate 15 is coaxially stacked with the anode 12, the micro-channel plate output electrode 11, the second-stage micro-channel plate 10, the first-stage micro-channel plate 9, the micro-channel plate input electrode 8, the intermediate ring 7, the grid 6, the grid electrode 5 and the upper cover plate 4 in sequence, and then a connecting screw 3 is screwed on the corresponding threaded hole of the bottom plate 17 through the corresponding through holes of the upper cover plate 4 and the isolation sleeve 14, to form a micro-channel plate assembly.

[0049] A support screw 16 is screwed on the corresponding threaded hole of the flange 19 through the through hole of the bottom plate 17 and the through hole of the support sleeve 18, to realize the connection between the micro-channel plate assembly and the flange.

[0050] The grid 6 plays a role of accelerating the particles to be detected, and a grid voltage can be applied through the grid electrode, so that the speed of the particles when entering the input surface of the microchannel plate 9 can be controlled by controlling the grid voltage.

[0051] The shielding cylinder 2 is located on the upper cover plate 4, and the assembly screw 1 passes through the through hole of the shielding cylinder 2 and is screwed on the corresponding threaded hole of the bottom plate 17 to realize the shielding of the assembly and effectively shield the influence of the external electric field on the detector.

[0052] The anode 12 is designed as a protruding cylinder 12b at the position of the axis, which is connected with the SMA joint 19b of the flange 19 after passing through the anode output capacitor 13 to realize the rapid output of the detection signal.

[0053] The electrode column 5a of the grid electrode 5, the electrode column 8a of the microchannel plate input electrode 8, the electrode column 11a of the microchannel plate output electrode 11 and the electrode column 12a of the anode 12 are all led out from the side and connected with the SHV joint 19a of the flange 19, so as to ensure that appropriate voltage is applied to the grid, the microchannel plate and the anode.

[0054] The circuit protection module 20 is connected with the SMA joint 19b of the flange.

[0055] As an optional embodiment, the shielding cylinder 2 has a middle through region 2b for particle incidence, and after assembly is completed, the shielding cylinder 2 leaves a gap 21 from the flange 19 to facilitate the detector to quickly complete the vacuumizing action before formal use.

[0056] In combination with Figure 1 , Figure 6 As shown in the figure, the circuit protection module 20 is composed of a high-voltage isolation capacitor 20a and a protection circuit diode 20b in electrical connection. For example, two protection circuit diodes 20b are connected in reverse parallel and connected in series with the high-voltage isolation capacitor 20a to form the circuit protection module 20, which is connected to the SMA joint 19b of the flange to realize output protection and ensure that other parts in the system are not damaged when the microchannel plate detector fails, thereby ensuring the safety during use.

[0057] In the design of the microchannel plate detector in the embodiment of the application, the parts working in a vacuum environment are mainly composed of metal, ceramic and lead silicate glass, and the outgassing amount is small.

[0058] For example, the materials of the assembly screw 1, the shielding cylinder 2, the connecting screw 3, the grid electrode 5, the grid 6, the microchannel plate input electrode 8, the support screw 16 and the bottom plate 17 are all stainless steel.

[0059] The materials of the upper cover plate 4, the middle ring 7, the isolation sleeve 14, the lower cover plate 15 and the support sleeve 18 are all ceramic.

[0060] The material of the first-stage micro-channel plate 9 and the second-stage micro-channel plate 10 is lead silicate glass, and the amount of gas emission during operation is small.

[0061] As a preferred embodiment, the substrate of the micro-channel plate output electrode 11 is ceramic, and the side 10a in contact with the second-stage micro-channel plate 10 is plated with a gold layer; the electrode column 11a of the side of the micro-channel plate output electrode 11 is made of stainless steel. The micro-channel plate output electrode 11 has the functions of applying voltage to the micro-channel plate and insulating the micro-channel plate and the anode, and has a compact structure and reduces the amount of gas emission during operation.

[0062] As a preferred embodiment, the medium of the anode output capacitor 13 is ceramic, and the amount of gas emission during operation is small.

[0063] {Example 2}

[0064] In combination Figures 1-4 and Figure 6 As shown in the drawings, in the embodiment of the present application, a preparation method of a flange-type micro-channel plate detector applied in an ultra-high vacuum environment is provided, which comprises the following steps:

[0065] Step 1, place the lower cover plate 15 on the bottom plate 17, and place the isolation sleeve 14 coaxially with the peripheral hole of the lower cover plate 15.

[0066] Step 2, sequentially coaxially stack the anode 12, the micro-channel plate output electrode 11, the second-stage micro-channel plate 10, the first-stage micro-channel plate 9, the micro-channel plate input electrode 8, the middle ring 7, the grid 6, the grid electrode 5, and the upper cover plate 4 on the lower cover plate 15, pass the connecting screw 3 through the corresponding through holes of the upper cover plate 4 and the isolation sleeve 14, and screw it on the corresponding threaded hole of the bottom plate 17 to form a micro-channel plate assembly.

[0067] Step 3, connect one end of the capacitor 13 with the protruding cylinder 12b of the anode together, and connect the other end with the SMA joint 19b of the flange together.

[0068] Step 4, pass the support screw 16 through the through hole of the bottom plate and the through hole of the support sleeve 18, and screw it on the corresponding threaded hole of the flange 19 to realize the connection of the micro-channel plate assembly and the flange.

[0069] Step 5, connect the electrode column 5a of the grid electrode 5, the electrode column 8a of the micro-channel plate input electrode 8, the electrode column 11a of the micro-channel plate output electrode 11, and the electrode column 12a of the anode 12 with the SHV joint 19a of the corresponding flange respectively.

[0070] Step 6, place the shielding cylinder 2 on the upper cover plate 4, pass the assembly screw 1 through the through hole of the shielding cylinder 2, and screw it on the corresponding threaded hole of the bottom plate 17.

[0071] Step 7, connect the circuit protection module 20 with the SMA joint 19b of the flange together.

[0072] Therefore, the connection and fixation between the various parts of the microchannel plate detector are mainly completed through the assembly screws 1, the connecting screws 3 and the supporting screws 16, so as to realize the assembly of the flange-type microchannel plate detector in an ultra-high vacuum environment. The detector is designed to be detachable, and when a part is damaged, it can be directly replaced, which is convenient for maintenance.

[0073] {Example 3}

[0074] Combine Figure 6 As shown, according to Figure 6 The electrical schematic diagram of the microchannel plate detector was used to build a test system and apply voltage. The test showed that the gain reached 1.8×10 6 , the waveform is as follows Figure 7 As shown, the pulse half-width is 1.8 ns. It can be seen that the microchannel plate detector designed according to the embodiment of the present invention has the characteristics of high gain and fast time response.

[0075] While the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A flange-type microchannel plate detector for use in ultra-high vacuum environments, characterized in that: It comprises a shielding tube (2), an upper cover plate (4), a grid electrode (5), a grid (6), an intermediate ring (7), a microchannel plate input electrode (8), a first-stage microchannel plate (9), a second-stage microchannel plate (10), a microchannel plate output electrode (11), an anode (12), an anode output capacitor (13), an isolation sleeve (14), a lower cover plate (15), a bottom plate (17), a support sleeve (18), a flange (19), and a circuit protection module (20), wherein: An SHV connector (19a) and an SMA connector (19b) are welded to the flange (19), wherein the SHV connector (19a) is an electrode lead-out interface, and the SMA connector (19b) is a signal lead-out interface; The lower cover plate (15) is pressed onto the bottom plate (17), and the isolation sleeve (14) is coaxially placed with the peripheral hole of the lower cover plate (15); The anode (12), the microchannel plate output electrode (11), the second-stage microchannel plate (10), the first-stage microchannel plate (9), the microchannel plate input electrode (8), the intermediate ring (7), the grid (6), the grid electrode (5) and the upper cover (4) are coaxially stacked in sequence on the lower cover (15), and then a connecting screw (3) is used to pass through the corresponding through holes of the upper cover (4) and the isolation sleeve (14) and screwed onto the corresponding threaded hole of the bottom plate (17) to form a microchannel plate assembly; Use support screws (16) to pass through the through holes of the base plate (17) and the through holes of the support sleeve (18), and screw them onto the corresponding threaded holes of the flange (19) to achieve the connection between the microchannel plate assembly and the flange; The shielding cylinder (2) is located on the upper cover plate (4), and is assembled by screwing the screws (1) through the through holes of the shielding cylinder (2) and screwing them onto the corresponding threaded holes of the bottom plate (17) to achieve component shielding. The center axis of the anode (12) is designed as a raised cylinder (12b), and the raised cylinder is connected to the SMA connector (19b) of the flange (19) after passing through the anode output capacitor (13); The electrode column (5a) of the grid electrode (5), the electrode column (8a) of the microchannel plate input electrode (8), the electrode column (11a) of the microchannel plate output electrode (11), and the electrode column (12a) of the anode (12) are all led out from the side and connected to the SHV connector (19a) of the flange (19); The circuit protection module (20) is connected to the SMA connector (19b) of the flange.

2. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The shielding cylinder (2) has a middle through-region (2b) for particle incidence; and after assembly, a gap (21) is left between the shielding cylinder (2) and the flange (19).

3. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The circuit protection module (20) is electrically connected by a high-voltage isolation capacitor (20a) and a protection circuit diode (20b).

4. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The SHV connector (19a) and the SMA connector (19b) both pass through the flange (19) and extend outward from the flange (19).

5. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The materials of the assembly screws (1), shielding tube (2), connecting screws (3), grid electrode (5), grid (6), microchannel plate input electrode (8), supporting screws (16) and bottom plate (17) are all stainless steel.

6. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The materials of the upper cover plate (4), the intermediate ring (7), the isolation sleeve (14), the lower cover plate (15) and the support sleeve (18) are all ceramic.

7. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The material of the first-stage microchannel plate (9) and the second-stage microchannel plate (10) is lead silicate glass.

8. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The substrate of the microchannel plate output electrode (11) is ceramic, and a gold plating layer is deposited on the side (10a) in contact with the second-stage microchannel plate (10); The electrode column (11a) on the side of the microchannel plate output electrode (11) is made of stainless steel.

9. The flange-type microchannel plate detector for use in an ultra-high vacuum environment according to claim 1, characterized in that: The medium of the anode output capacitor (13) is ceramic.

10. The method for preparing a flange-type microchannel plate detector for use in an ultra-high vacuum environment according to any one of claims 1 to 9, characterized in that: The following steps are involved: Place the lower cover plate (15) on the base plate (17), and place the isolation sleeve (14) coaxially with the peripheral hole of the lower cover plate (15); On the lower cover plate (15), the anode (12), the microchannel plate output electrode (11), the second-stage microchannel plate (10), the first-stage microchannel plate (9), the microchannel plate input electrode (8), the intermediate ring (7), the grid (6), the grid electrode (5), and the upper cover plate (4) are coaxially stacked in sequence, and the connecting screws (3) are passed through the corresponding through holes of the upper cover plate (4) and the isolation sleeve (14) and screwed onto the corresponding threaded holes of the bottom plate (17) to form a microchannel plate assembly; Connect one end of the capacitor (13) to the anode raised cylinder (12b), and the other end to the SMA connector (19b) of the flange; Pass the support screw (16) through the through hole of the base plate and the through hole of the support sleeve (18), and screw it onto the corresponding threaded hole of the flange (19) to achieve the connection between the microchannel plate assembly and the flange; Connecting the electrode column (5a) of the grid electrode (5), the electrode column (8a) of the microchannel plate input electrode (8), the electrode column (11a) of the microchannel plate output electrode (11), and the electrode column (12a) of the anode (12) to the corresponding SHV connectors (19a) of the flanges respectively; Place the shielding tube (2) on the upper cover (4), pass the assembly screws (1) through the through holes of the shielding tube (2), and screw them into the corresponding threaded holes of the bottom plate (17); Connect the circuit protection module (20) to the SMA connector (19b) of the flange.

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