CN217062011U - Field emission electron source - Google Patents

Abstract

The present disclosure provides a field emission electron source, comprising: a base; the transmission subassembly sets up and includes on the base: an emission tip for emitting electrons; the first terminal is arranged below the emission tip and is used for being connected with a first negative high voltage; a second terminal disposed under the emission tip for connection with a second negative high voltage, an acceleration electrode disposed on the base for connection with a first positive high voltage, and for accelerating electrons emitted from the emission tip.

Description

Field emission electron source

Technical Field

The present disclosure relates to the field of electron beam generation, and more particularly, to a field emission electron source.

Background

The field emission electron source is widely applied to various fields such as production, scientific research and the like. Generally, a field emission electron source is an electron source based on applying a high electric field to a cathode tip to emit electrons. In thermal field emission, the cathode material is subjected to high temperature heating to transfer energy to electrons of higher energy levels, providing them with sufficient kinetic energy to overcome the work function so that they can escape the surface barrier of the solid cathode, forming an electron beam.

A field emission electron source plays a role of generating an electron beam in a Scanning Electron Microscope (SEM), and one of important points of SEM imaging is that an electron beam emitted from the electron source can be kept constant, and if the amount of electrons in the electron beam is reduced, the brightness of an SEM image is reduced, thereby causing problems such as a reduction in image resolution and a reduction in accuracy.

In order to maintain the stability of the electron beam emitted by the electron source in the prior art, the electron source is arranged in vacuum, however, as the field emission filament in the field emission electron source generates heat effect when current is added to high voltage, the filament base and the extraction electrode generate deformation, and the stability of the electron beam is reduced. In addition, some metals are prone to oxygen, nitrogen, etc. reaction at high temperature, which affects vacuum degree and causes pollution to the vacuum chamber.

In addition, in the process of generating electron beams, high-energy electrons splash to easily cause damage to an electron source, so that the device has great destructive power, and the service life of the device is greatly reduced. In order to solve the problem, martin.j.a. and lagally.m.g use a low-energy electron source in the electron gun, and electrons in the electron beam extracted from the cathode have lower kinetic energy, which can reduce the damage of the device, but the whole device has a complex structure and is inconvenient to disassemble, assemble and maintain.

SUMMERY OF THE UTILITY MODEL

The present disclosure provides a field emission electron source, comprising: a base; the transmission subassembly sets up and includes on the base: an emission tip for emitting electrons; the first terminal is arranged below the emission tip and is used for being connected with the first negative high voltage; a second terminal disposed under the emission tip for connection with a second negative high voltage, an acceleration electrode disposed on the base for connection with a first positive high voltage, and for accelerating electrons emitted from the emission tip.

In some embodiments, the transmission assembly further comprises: and the insulating support is used for supporting the first terminal and the second terminal so as to insulate the first terminal and the second terminal from the base.

In some embodiments, the transmission assembly further comprises: and the emission shell is arranged on the insulating support, is insulated from the first terminal and the second terminal, is used for accommodating the emission tip and is connected with the third negative high voltage, wherein the top end of the emission shell comprises an emission hole matched with the emission tip, and electrons emitted by the emission tip pass through the emission hole.

In some embodiments, the field emission electron source further comprises: and the grounding switch is electrically connected with the accelerating electrode.

In some embodiments, an accelerating electrode is insulatively mounted on the base, the accelerating electrode including an accelerating aperture aligned with the emission aperture, electrons passing through the emission aperture being accelerated and emitted through the accelerating aperture.

In some embodiments, the accelerating electrode comprises a tantalum electrode sheet, a tantalum electrode layer, or a tantalum electrode block; and/or the base is an integrally formed oxygen free copper base.

In some embodiments, the susceptor includes a first mounting groove having a top surface, a recess, or a flange at the top, and the accelerating electrode is mounted on the top surface, in the recess, or on the flange.

In some embodiments, the susceptor further includes a second mounting groove, the field emission electron source further comprising: the first molybdenum conductor is arranged in the second mounting groove, is electrically connected with the first terminal and is used for being connected with a first negative high voltage; and a second molybdenum conductor disposed in the second mounting groove, insulated from the first molybdenum conductor, electrically connected to the second terminal, and adapted to be connected to a second negative high voltage.

In some embodiments, the base further comprises: the partition plate is arranged between the first mounting groove and the second mounting groove; the bottom plate is arranged below the second mounting groove; and the through grooves are formed in the bottom plate and used for accommodating the conductive pieces.

In some embodiments, the field emission electron source further comprises: the base is arranged on the mounting flange; the first high-voltage electric feed-through is arranged on the mounting flange and used for communicating a first negative high voltage with the first terminal; the second high-voltage electric feed-through is arranged on the mounting flange and is used for communicating a second negative high voltage with the second terminal; and a third high voltage electrical feedthrough disposed at the mounting flange for communicating the first positive high voltage with the accelerating electrode.

In some embodiments, the first high voltage electrical feedthrough has an operating voltage of 0kV to 25kV, the second high voltage electrical feedthrough has an operating voltage of 0kV to 25kV, and the third high voltage electrical feedthrough has an operating voltage of 0kV to 25 kV.

In some embodiments, the field emission electron source further comprises at least one secondary mounting flange disposed on the mounting flange for mounting at least one additional high voltage electrical feedthrough.

In some embodiments, the field emission electron source further comprises: the water cooling assembly is connected with the base and used for cooling the base, the water cooling assembly comprises a water inlet pipe, a water outlet pipe and a circulation cavity, the water inlet pipe is sleeved outside the water outlet pipe, the circulation cavity is arranged on the lower surface of the base, and one end of the water inlet pipe and one end of the water outlet pipe are communicated with the circulation cavity.

The field emission electron source according to some embodiments of the present disclosure can bring about advantageous technical effects. For example, the field emission electron source of some embodiments of the present disclosure can solve the problems that high-energy electrons easily cause electron source damage due to splashing in the conventional technology, the service life of the equipment is shortened, the equipment structure is complex, the assembly, disassembly and maintenance are inconvenient, metal is easy to react with oxygen, nitrogen and the like at high temperature, the vacuum degree is affected, the vacuum cavity is polluted and the like, and can achieve the technical effect of reducing the high-temperature equipment damage of the whole electron source due to voltage and electron splashing. Meanwhile, the equipment of some embodiments of the present disclosure has stable material properties, is not easy to pollute the vacuum cavity, and has simple structure and convenient assembly, disassembly and maintenance.

Drawings

In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only one embodiment of the present disclosure, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 shows a schematic view of a field emission electron source, according to some embodiments of the present disclosure;

figure 2 shows an exploded view of a structure of a field emission electron source according to some embodiments of the present disclosure;

FIG. 3 illustrates a schematic structural diagram of a launch assembly according to some embodiments of the present disclosure;

FIG. 4 shows a schematic structural view of a firing tip according to some embodiments of the present disclosure;

FIG. 5 shows a schematic structural view of an accelerating electrode according to some embodiments of the present disclosure;

FIG. 6 illustrates a schematic structural view of a base according to some embodiments of the present disclosure;

fig. 7 shows a schematic structural view of a first molybdenum conductor according to some embodiments of the present disclosure;

FIG. 8 illustrates a structural schematic of a mounting flange according to some embodiments of the present disclosure.

In the above drawings, the respective reference numerals denote:

100 field emission electron source

10 base

11 emission area

12 acceleration zone

13 first mounting groove

14 second mounting groove

15 depressions

151a, 151b, 151c first screw hole

152a, 152b second screw hole

16 partition board

17 bottom plate

18 through groove

20 transmitting assembly

21 emitting tip

22 first terminal

23 second terminal

24 insulating support

25 emission casing

251 emission hole

30 accelerating electrode

31 acceleration hole

32a, 32b mounting

321a, 321b short board

3211a, 3211b first mounting hole

322a, 322b long plate

3221 second mounting hole

40a first molybdenum conductor

40b second molybdenum conductor

41a first fixing hole

42a second fixing hole

43a connecting hole

50 mounting flange

51 first high-voltage electric feed-through

52 second high-voltage electrical feedthrough

53 third high voltage electrical feedthrough

54 fourth high-voltage electric feed-through

55 auxiliary mounting flanges

60 water-cooling assembly

61 water inlet pipe

62 outlet pipe

63 circulation chamber

Detailed Description

Some embodiments of the present disclosure will be described below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the disclosure and that not all embodiments are intended to be considered.

In the description of the present disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings, only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and operate, and thus, should not be construed as limiting the present disclosure. In the description of the present disclosure, the direction of electron emission is taken as the top, and the opposite direction is taken as the bottom. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present disclosure, it should be noted that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "coupled" are to be construed broadly and may include, for example, a fixed connection or a removable connection; can be mechanically or electrically connected; the connection can be direct connection or indirect connection through an intermediate medium; there may be communication between the interiors of the two elements. The specific meaning of the above terms in the present disclosure can be understood by those of ordinary skill in the art as appropriate.

Fig. 1 illustrates a schematic structural view of a field emission electron source 100 according to some embodiments of the present disclosure. Fig. 2 illustrates an exploded view of the structure of a field emission electron source 100 according to some embodiments of the present disclosure.

As shown in fig. 1 and 2, an embodiment of the present disclosure provides a field emission electron source 100 including a base 10, an emission member 20, and an accelerating electrode 30. The susceptor 10 may include an emission region 11 and an acceleration region 12. The emitting assembly 20 is disposed on the base 10 in the emitting region 11. Fig. 3 shows a schematic structural view of the emission assembly 20 according to some embodiments of the present disclosure, and fig. 4 shows a schematic structural view of the emission tip 21 according to some embodiments of the present disclosure. As shown in fig. 4, the transmission assembly 20 includes: an emission tip 21 that can be used to emit electrons; a first terminal 22, disposed under the emission tip 21, which may be used for connection with a first negative high voltage; a second terminal 23, arranged below the emission tip, may be used for connection with a second negative high voltage. An accelerating electrode 30 may be disposed on the base 10 at the accelerating region 12, may be used for connection with the first positive high voltage, and may be used for emitting electrons emitted from the tip 21.

The emission tip 21 may be a single-crystal tungsten wire having an axial direction of <100> and covered with a zirconia coating. The zirconia coating can significantly reduce the work function of the emission tip 21, thereby improving the emission efficiency of electrons.

It will be understood by those skilled in the art that although the embodiment has been described with a single crystal tungsten wire covered with a zirconia coating as the emission tip 21, other materials that can also lower the work function of the emission tip 21 may be used.

As shown in fig. 3 and 4, in some embodiments, the radiation assembly 20 further includes an insulating support 24 that may be used to support the first terminal 22 and the second terminal 23 to insulate the first terminal 22 and the second terminal 23 from the base 10.

The insulating support 24 is a cylindrical structure, and the thickness of the insulating support is smaller than the length of the first terminal 22 and the second terminal 23, so that the first terminal 22 and the second terminal 23 can be arranged on the insulating support 24 in a penetrating mode in parallel. The insulating support 24 may be made of insulating ceramic, and is capable of insulating the first terminal 22 and the second terminal 23 from the base 10.

It will be appreciated by those skilled in the art that while the insulating support 24 is shown in the present disclosure as having a cylindrical configuration, the insulating support 24 may also have a cylindrical configuration with a square, rectangular, hexagonal, etc. cross-section. It will be appreciated by those skilled in the art that while the insulating support 24 of the present disclosure is made of an insulating ceramic, the insulating support 24 may be made of any insulating material capable of supporting.

In some embodiments, the emitter assembly 20 further comprises an emitter housing 25, disposed on the insulating support 24 and insulated from the first and second terminals 22, 23, which may be used to house the emitter tip 21. The transmitting housing 25 may be connected to a third negative high voltage. Wherein the top end of the emission housing 25 includes an emission hole 251 adapted to the emission tip 21, and electrons emitted from the emission tip 21 enter the acceleration zone 12 through the emission hole 251.

The transmitting casing 25 is a cylinder with a hollow interior and an open bottom, and is sleeved outside the insulating support 24 or arranged on the insulating support 24. The inner diameter of the firing housing 25 matches the outer diameter of the insulator support 24 and the top firing aperture 251 is aligned with the firing tip 21.

It will be appreciated by those skilled in the art that while the emissive housing 25 in the present disclosure is a cylinder with a hollow interior and an open bottom, the emissive housing 25 may also be a cylindrical structure with a square, rectangular, hexagonal, etc. cross-section that matches the dielectric support 24. Similarly, although the emission casing 25 is provided with the emission hole 251 at the top thereof in the present disclosure, the emission casing 25 may be opened at the top thereof such that the emission tip 21 is directly exposed to the emission region 11, as will be understood by those skilled in the art.

In some embodiments, the field emission electron source 100 further includes a ground switch (not shown in the drawings). The ground switch is electrically connected to the accelerating electrode 30.

The grounding switch may be used to control the accelerating electrode 30 to be grounded or suspended. When the grounding switch is turned off, the accelerating electrode 30 is in a floating state, and is connected to the first positive high voltage, and the accelerating electrode 30 can be used to accelerate electrons emitted from the emission tip 21. When the ground switch is turned on, the accelerating electrode 30 is in a grounded state and does not accelerate electrons emitted from the emission tip 21. The selection can be made according to the needs of the user without shutting down the machine.

Fig. 5 shows a schematic structural view of an accelerating electrode 30 according to some embodiments of the present disclosure.

As shown in fig. 5, in some embodiments, the accelerating electrodes 30 are insulatively mounted on the base 10. The acceleration electrode 30 may include an acceleration hole 31 aligned with the emission hole 251, and the electrons passing through the emission hole 251 are accelerated by the acceleration region and then are emitted through the acceleration hole 31.

In some embodiments, the accelerating electrode 30 comprises a tantalum electrode sheet, a tantalum electrode layer, or a tantalum electrode block.

The accelerating electrode 30 is made of metal tantalum, and can resist high temperature. The emission tip 20 generates a heat effect when current is applied to apply high voltage, the accelerating electrode 30 located above the emission tip 20 absorbs heat radiation, and the accelerating electrode 30 made of tantalum metal is not easily deformed at high temperature, so that the stability of electron beams can be improved.

It will be appreciated by those skilled in the art that although the accelerating electrode 30 made of metallic tantalum is used in the present disclosure, the accelerating electrode can be other conductive and high temperature resistant materials.

In some embodiments, as shown in fig. 5, the accelerating electrode 30 is in a circular sheet shape, the thickness of the accelerating electrode can be about 0.5-10mm, the center of the circle is provided with an accelerating hole 31, and the diameter of the accelerating hole can be about

Accelerating electrode 30 mountingThe distance between the accelerating electrode 30 and the emission tip may be about 0.5-10mm on the base 10 above the emission tip 21. The accelerating aperture 31, the emitting aperture 251 and the apex-most point of the emitting tip 21 are aligned, e.g. on the same axis or aligned in some other way. The accelerating electrode 30 has two inverted L-shaped mounts 32a, 32b extending symmetrically in its radial direction, the mounts 32a, 32b including transverse plates 321a, 321b and risers 322a, 322b, respectively. The horizontal plates 321a and 321b are respectively provided with first mounting holes 3211a and 3211b, and the vertical plates 322a and 322b are respectively provided with second mounting holes 3221a (not shown) and 3221 b. The acceleration electrode 30 is fixed on the top of the base 10 and located in the acceleration region 11 by screws passing through the first mounting holes 3211a, 3211b and screws passing through the second mounting holes 3221a, 3221 b.

It will be understood by those skilled in the art that although the accelerating electrode 30 is shown in fig. 5 as a circular sheet, the accelerating electrode 30 may also be a layered or block structure. Similarly, the accelerating electrode 30 may have a square, diamond, rectangle or other shape that can be adapted to the base 10. Similarly, it will be understood by those skilled in the art that the thickness of the accelerating electrode 30, the aperture of the accelerating aperture 31, and the distance between the accelerating electrode 30 and the emitting tip are not limited in this disclosure, and in practical applications, the user can adjust the above values within a certain range according to the needs.

Fig. 6 illustrates a schematic structural view of the base 10 according to some embodiments of the present disclosure.

As shown in fig. 6, in some embodiments, the base 10 is an oxygen free copper base. The oxygen-free copper base can reduce the frequency of occurrence of high-temperature equipment damage to the entire field emission electron source 100 due to voltage pole electron splash, and solve the problem of inefficient principle performance of the field emission electron source 100.

It will be appreciated by those skilled in the art that although an oxygen-free copper base is illustrated in the present disclosure, the base 10 may be any other material that achieves similar technical results as described above.

In some embodiments, the susceptor 10 further includes a first mounting groove 13, the first mounting groove 13 having a top surface, a flange, or a recess, e.g., an inwardly or outwardly extending flange, at the top, and the accelerating electrode 30 mounted on the top surface, in the recess, or on the flange.

As shown in fig. 6, the base 10 is cylindrical, and has a recess 15 at the top, and the recess 15 is provided with first screw holes 151a, 151b, and 151c matching with the first mounting holes 3211a and 3211 b. The outer side wall of the base 10 is provided with second screw holes 152a (not shown) and 152b matching with the second mounting holes 3221.

The screw rods are inserted into the first screw holes 151a and 151b through the first mounting holes 3211a and 3211b to fix the accelerating electrode 30 to the recess 15, and the nut is fixed to the recess 15 by the screw rod inserted through the second screw hole 151c to press the accelerating electrode 30 against the recess 15 for auxiliary fixation.

It will be understood by those skilled in the art that although the base 10 is shown in fig. 6 as being cylindrical, the base 10 may be a cylindrical structure having a rectangular, square, hexagonal, etc. cross-section. It will be understood by those skilled in the art that although the accelerating electrode 30 is detachably mounted on the base 10 by screws and nuts in the present disclosure, the accelerating electrode 30 can be fixed on the base 10 by adhesion, fitting, clamping, etc.

It will be understood by those skilled in the art that, although not shown in the drawings, an insulating member, such as a ceramic spacer, may be disposed between the accelerating electrode 30 and the susceptor 10 for electrically insulating the accelerating electrode 30 from the susceptor 10.

In some embodiments, the base 10 further includes a second mounting slot 14.

In some embodiments, the base 10 further includes a spacing plate 16 disposed between the first mounting groove 13 and the second mounting groove 14, a bottom plate 17 disposed below the second mounting groove 14, and a plurality of through slots 18 opened on the bottom plate, which can be used to accommodate conductive members, so that the electrical components of the field emission electron source 100 are conveniently and orderly mounted.

It will be understood by those skilled in the art that although the bottom plate 17 is shown in fig. 6 as having a certain distance from the bottom surface of the second mounting groove 14 for facilitating wire connection, the bottom plate 17 may be directly mounted on the bottom surface of the second mounting groove 14. In some embodiments, the base 10 is an integrally formed oxygen free copper base.

In some embodiments, as shown in fig. 2, the field emission electron source 100 further includes a first molybdenum conductor 40a, a second molybdenum conductor 40 b. As shown in fig. 1, a first molybdenum conductor 40a is disposed in the second mounting groove 14, electrically connected to the first terminal 22 and for connection to a first negative high voltage. And a second molybdenum conductor 40a arranged in the second mounting groove 14, insulated from the first molybdenum conductor 40a, electrically connected with the second terminal 23 and used for connecting with a second negative high voltage.

The first molybdenum conductor 40a and the second molybdenum conductor 40b have similar structures and installation relationships, and only the first molybdenum conductor 40a is taken as an example for explanation, and a person skilled in the art can understand the second molybdenum conductor 40b through the description of the first molybdenum conductor 40a, and details are not repeated here.

Fig. 7 shows a schematic of a first molybdenum conductor 40a, according to some embodiments of the present disclosure.

As shown in fig. 7, the first molybdenum conductor 40a has a Z-shaped structure integrally formed with the second mounting groove 14, and has a first fixing hole 41a and a second fixing hole 42 a. The first molybdenum conductor 40a is fixed in the second mounting groove 14 by screws passing through the first fixing holes 41a and the second fixing holes 42a, and all surfaces of the first molybdenum conductor 40a contacting the second mounting groove 14 may be provided with ceramic gaskets for insulation from the second mounting groove 14. A connection hole 43a is formed on the top surface of the first molybdenum conductor 40a, and the first terminal 22 is inserted into the connection hole 43a to be conducted with the first molybdenum conductor 40a, so that the emission tip 21 is connected with the first negative high voltage.

A ceramic pad is also provided between the first and second molybdenum conductors 40a, 40b and is only conducted through the tip of the emitter 21. The first molybdenum conductor 40a can resist high temperature, and easily generates a heat effect when current is applied to increase the voltage, and the first molybdenum conductor 40a is not easily deformed at high temperature, so that the stability of the electron beam can be improved.

In some embodiments, the field emission electron source 100 may further include a mounting flange 50, as shown in fig. 1 and 2. FIG. 8 illustrates a structural schematic of a mounting flange 50 according to some embodiments of the present disclosure. As shown in fig. 8, the mounting flange 50 is provided with a first high voltage electrical feedthrough 51 that may be used to communicate the first negative high voltage with the first terminal 22, a second high voltage electrical feedthrough 52 that may be used to communicate the second negative high voltage with the second terminal 23, and a third high voltage electrical feedthrough 53 that may be used to communicate the first positive high voltage with the accelerating electrode 30.

In some embodiments, the first high voltage electrical feed-through 51 has an operating voltage of 0kV to 25kV, the second high voltage electrical feed-through 52 has an operating voltage of 0kV to 25kV, and the third high voltage electrical feed-through 53 has an operating voltage of 0kV to 25 kV.

In some embodiments, the mounting flange 50 further includes a fourth high voltage electrical feedthrough 54 that may be used to communicate the third negative high voltage with the emission enclosure 25, such that the emission enclosure 25 may inhibit the emission tip 21 from dispersing emitted electrons, thereby allowing the electron beam to be more focused and increasing the emission efficiency.

In some embodiments, the mounting flange 50 may also include at least one secondary mounting flange 55 that may be used to mount at least one additional device, such as a high voltage electrical feedthrough, a water cooling device (such as water cooling assembly 60 shown in FIG. 2), and the like.

It will be appreciated by those skilled in the art that although only one secondary mounting flange 55 and one additional water cooling assembly 60 are shown in FIG. 8, two or more secondary mounting flanges 55 may be provided on the mounting flange 50 for mounting two or more additional devices.

In some embodiments, the field emission electron source 100 may further include a water-cooling member 60, as shown in fig. 2. A water cooling assembly 60 is provided in the mounting flange 55 and is connected to the base 10 and can be used to cool the base. The water cooling unit 60 includes an inlet pipe 61, an outlet pipe 62, and a circulation chamber 63. The water inlet pipe 61 is sleeved outside the water outlet pipe 62, the circulating cavity 63 is arranged on the lower surface of the base 10, and one ends of the water inlet pipe 61 and the water outlet pipe 62 are installed and communicated with the circulating cavity 63. The water-cooling unit 60 can improve the operation stability of the field emission electron source 100 and maintain the degree of vacuum by cooling the susceptor 10.

According to the invention, negative high voltage is introduced through the first terminal 22 and the second terminal 23, so that the emission tip 21 generates high voltage, and the first positive high voltage communicated with the accelerating electrode 30 is matched, so that a higher potential difference is generated between the emission tip and the accelerating electrode 30, electrons can be extracted from the emission tip 21, and high speed (up to 1.5 e) is formed ^-8 km/h) of a high-energy electron beamIs emitted into vacuum. The power of electron beam acceleration can be adjusted by adjusting the current value of the emission tip 21, the negative voltage values of the first negative high voltage and the second negative high voltage, and the voltage value of the acceleration electrode 30. The field emission electron source 100 of the present disclosure can operate in an ultra-high vacuum environment, for example, up to 1.0 × 10 ^-10 A vacuum environment of mbar. And the field emission electron source 100 of the present disclosure can efficiently focus a beam spot that is small, for example, up to 0.25mm phi at minimum.

It should be understood that the above description is only exemplary of the preferred embodiments of the present disclosure, and is not intended to limit the present disclosure to the particular forms disclosed, and all modifications, equivalents, improvements, and equivalents that fall within the spirit and scope of the present disclosure are intended to be embraced thereby.

Claims (13)

1. A field emission electron source, comprising:

a base;

a launch assembly disposed on the base comprising:

an emission tip for emitting electrons;

a first terminal disposed under the emission tip for connection with a first negative high voltage;

a second terminal disposed under the emission tip for connection with a second negative high voltage,

and the accelerating electrode is arranged on the base, is used for being connected with the first positive high voltage and is used for accelerating the electrons emitted by the emitting tip.

2. The field emission electron source of claim 1, wherein the emission component further comprises:

and an insulating support for supporting the first terminal and the second terminal to insulate the first terminal and the second terminal from the base.

3. The field emission electron source of claim 2, wherein the emission component further comprises:

a transmitting housing disposed on the insulating support and insulated from the first and second terminals for accommodating the transmitting tip and connected to a third negative high voltage,

wherein, the transmission shell top includes with the transmission hole of transmission tip looks adaptation, the electron that the transmission tip was launched passes through the transmission hole.

4. The field emission electron source of claim 1, further comprising: a ground switch electrically connected to the accelerating electrode.

5. The field emission electron source according to claim 3,

the accelerating electrode is arranged on the base in an insulating mode, the accelerating electrode comprises an accelerating hole aligned with the emission hole, and electrons passing through the emission hole are accelerated and then are emitted through the accelerating hole.

6. The field emission electron source according to claim 1,

the acceleration electrode comprises a tantalum electrode plate, a tantalum electrode layer or a tantalum electrode block; and/or

The base is an integrally formed oxygen-free copper base.

7. The field emission electron source of claim 1, wherein the base comprises a first mounting groove having a top surface, a recess, or a flange at a top thereof, the accelerating electrode being mounted on the top surface, in the recess, or on the flange.

8. The field emission electron source of claim 7, wherein the base further comprises a second mounting groove,

the field emission electron source further includes:

the first molybdenum conductor is arranged in the second mounting groove, is electrically connected with the first terminal and is used for being connected with the first negative high voltage; and

and the second molybdenum conductor is arranged in the second mounting groove, is insulated from the first molybdenum conductor, is electrically connected with the second terminal and is used for being connected with a second negative high voltage.

9. The field emission electron source of claim 8, wherein the base further comprises:

the partition plate is arranged between the first mounting groove and the second mounting groove;

the bottom plate is arranged below the second mounting groove; and

and the through grooves are formed in the bottom plate and used for accommodating the conductive pieces.

10. The field emission electron source of any of claims 1-9, further comprising:

the base is arranged on the mounting flange;

a first high voltage electrical feedthrough disposed on the mounting flange for communicating the first negative high voltage with the first terminal;

a second high voltage electrical feedthrough disposed on the mounting flange for communicating the second negative high voltage with the second terminal; and

and the third high-voltage electric feed-through is arranged on the mounting flange and is used for communicating the first positive high voltage with the accelerating electrode.

11. The field emission electron source according to claim 10,

the working voltage of the first high-voltage electric feed-through is 0kV to 25kV,

the working voltage of the second high-voltage electric feed-through is 0kV to 25kV,

the working voltage of the third high-voltage electric feed-through is 0 kV-25 kV.

12. The field emission electron source of claim 10, further comprising:

and the auxiliary mounting flange is arranged on the mounting flange and is used for mounting at least one additional device.

13. The field emission electron source according to claim 1, further comprising:

a water cooling component connected with the base and used for cooling the base,

the water cooling component comprises a water inlet pipe, a water outlet pipe and a circulating cavity,

wherein the water inlet pipe is sleeved outside the water outlet pipe,

the circulating cavity is arranged on the lower surface of the base,

one end of the water inlet pipe and one end of the water outlet pipe are communicated with the circulating cavity.

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