Multi-anode electron emission device, electron gun and semiconductor equipment

Abstract

The utility model discloses a multi-anode electron emission device, an electron gun and semiconductor equipment, the electron emission device is used for a micro-focal spot electron gun, the electron emission device comprises a cathode, a grid electrode and an anode part, and the cathode is used for releasing electrons. The anode part is arranged at the downstream of the cathode, and the anode part and the cathode are arranged at an interval and used for attracting and accelerating electrons released by the cathode to form electron beams. And the grid is arranged between the cathode and the anode part, is connected with negative voltage and is used for regulating and controlling the electric field intensity on the surface of the cathode. And gaps are formed between the grid electrode and the cathode and between the grid electrode and the anode part. The anode part comprises a plurality of anode plates, the plurality of anode plates are arranged at intervals, the voltages of the plurality of anode plates are sequentially increased from upstream to downstream, and the plurality of anode plates are used for forming an electric field for focusing electron beams. By arranging the anode part comprising a plurality of anode plates, an electric field capable of primarily focusing electron beams is formed, the divergence problem of the electron beams is solved, the quality of cross spots is improved, and an electric field better meeting the use requirements of the electron gun can be formed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electron guns, and particularly relates to a multi-anode electron emission device and an electron gun and a semiconductor device. BACKGROUND

[0002] An electron gun is a device for generating, accelerating and converging high-energy density electron beams, which can emit electron beams with certain energy, beam current, speed and angle, and is also called an electron beam. The electron gun can be applied to display circuits, fluorescent screens and the like. Generally, the electron gun includes two parts: one part is an emission system capable of emitting electrons and capable of preliminary focusing; and the other part is a focusing system capable of focusing the electron beams from the emission system into images. The beam spot at the receiving end of the electron gun can be regarded as an image of the cross spot of the beam current obtained by the emission system, and the cross spot obtained by the emission system is a key to determine the performance of the electron gun.

[0003] In the structure of the electron gun, a large number of hot electrons can be generated on the surface of the cathode after the cathode is powered and heated. Under the action of the high-voltage electric field between the anode and the cathode, the hot electrons move at high speed toward the anode and obtain high kinetic energy. The existing electron emission device of the electron gun basically uses electrostatic electrode grids and anodes to emit electrons. An acceleration electric field is arranged between the cathode and the anode to accelerate the electrons. The emitted electrons must pass through the holes in the anode, and the holes in the anode will cause electric field distortion, so that the acceleration electric field between the holes of the electrostatic electrode is no longer a uniform acceleration field, and thus the electron beam begins to diverge from the emission end. In addition, during the electron emission stage, the space charge repulsion force between the electrons will also cause the electron beam to diverge. In the actual application of the electron gun, the electron beam needs to be focused to a certain extent, and the relatively divergent electron beam due to insufficient focusing will adversely affect the application of the electron gun, for example, the quality of the beam spot formed by the electron beam will be affected. CONTENT OF THE UTILITY MODEL

[0004] The present application is made in view of the above-mentioned state of the art. The present application discloses a multi-anode electron emission device and an electron gun and a semiconductor device, which are used to solve the problems of electron beam divergence and insufficient electron beam focusing degree existing in the existing electron emission device and electron gun.

[0005] In a first aspect, the present application provides a multi-anode electron emission device for a micro-focal spot electron gun, which includes a cathode, a grid and an anode part,

[0006] The cathode is used to release electrons,

[0007] The anode part is arranged downstream of the cathode, and is arranged in a spaced manner with the cathode, and is used to attract and accelerate the electrons released by the cathode to form an electron beam,

[0008] The gate is arranged between the cathode and the anode part, the gate is connected to a negative voltage, and is used to regulate the electric field intensity on the surface of the cathode,

[0009] The gate is spaced apart from the cathode and the anode part,

[0010] The anode part comprises a plurality of anode plates, the plurality of anode plates are arranged in a spaced apart manner, and the voltage of the plurality of anode plates gradually increases from upstream to downstream, and the plurality of anode plates are used to form an electric field for focusing the electron beam.

[0011] The multi-anode electron emission device improves the anode electric field distortion by arranging the anode part comprising a plurality of anode plates, forms an electric field capable of preliminarily focusing the electron beam, improves the divergence problem of the electron beam, and improves the quality of the cross spot. The anode part is arranged with a plurality of anode plates, which can flexibly adjust the voltage difference between the anode plates according to the actual use requirements of the electron gun, form an electric field more in line with the use requirements of the electron gun, and improve the focusing effect of the electron beam. The multi-anode electron emission device further comprises a gate connected to a negative voltage, which is also called a control gate. As the control electrode of the electron, the gate is close to the cathode. By changing the voltage between the gate and the cathode, the electric field intensity on the surface of the cathode can be changed, and then the emission of the electron current from the cathode and the density of the electron current can be controlled.

[0012] In a possible implementation, the plurality of anode plates are arranged along the axial direction of the multi-anode electron emission device.

[0013] Arranging the plurality of anode plates along the axial direction can better gradually accelerate the electron beam.

[0014] In a possible implementation, the gate is connected to a negative voltage direct current, and the anode part is connected to a positive voltage direct current.

[0015] Connecting the gate and the anode part to direct current is more suitable for adjusting the electron beam, and the structure is simple and can save the occupied space of the electron emission device.

[0016] In a possible implementation, the voltage difference between adjacent anode plates is equal.

[0017] Changing the voltage of the plurality of anode plates in an arithmetic progression can form a more uniform electric field.

[0018] In a possible implementation, the anode plate is a flat plate-shaped anode formed with a hole, and the hole is used for passing electrons.

[0019] Compared with the anode structures such as a cylindrical anode and a conical anode, the flat plate-shaped anode has better uniformity of the formed electric field, has smaller electric field distortion, and can reduce the divergence of the electron beam caused by the non-uniformity of the anode electric field.

[0020] In a possible implementation, the anode part includes a first anode plate, a second anode plate, a third anode plate, and a fourth anode plate.

[0021] The anode part is provided with four anode plates as a preferred structure, which can better form an electric field capable of focusing an electron beam.

[0022] In a possible implementation, the plurality of anode plates are of the same size, and the spacing between the plurality of anode plates is equal.

[0023] The plurality of anode plates are of the same size and are equally spaced, which can form a more uniform uniform electric field and better focus the electron beam. In addition, using anode plates of the same size can also make the structure of the multi-anode electron emission device simpler, reduce manufacturing costs, and save the occupied space of the device.

[0024] In a second aspect, the present application provides an electron gun, including the multi-anode electron emission device described above; and a focusing system arranged downstream of the multi-anode electron emission device, for focusing the electron beam formed by the multi-anode electron emission device.

[0025] The anode part including a plurality of anode plates can preliminarily focus the electron beam and obtain a better cross spot, thereby improving the beam spot quality of the electron gun. The electron beam has been preliminarily focused in the emission device, which can also make the design of the focusing system more flexible.

[0026] In a possible implementation, the focusing system includes an electrostatic lens and / or a magnetic lens.

[0027] The electrostatic lens and the magnetic lens are the main forms of electron lenses, which can effectively focus the electron beam and improve the performance of the electron gun.

[0028] In a possible implementation, the number of the electrostatic lens and / or the magnetic lens is multiple.

[0029] By arranging multiple electron lenses, the focusing degree of the electron beam can be further improved, and the quality of the beam spot can be improved.

[0030] In a possible implementation, the focusing system includes a magnetic lens, and the magnetic lens includes a coil and a pole piece, and the pole piece at least partially wraps the coil.

[0031] The pole piece can improve the strength and uniformity of the magnetic field, thereby improving the focusing ability of the magnetic lens on the electron beam.

[0032] In a third aspect, the present application also provides a semiconductor device, including the electron gun described above, and a monochromator arranged downstream of the electron gun, the monochromator being used for filtering X-rays.

[0033] The semiconductor device provides a preferred application scenario of the aforementioned electron gun, which can utilize the electron gun to emit an electron beam to bombard a target material, and the target material generates X-rays which are irradiated to a sample after being filtered by a monochromator. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0035] Figure 1 The working principle schematic diagram of the electron emission device and the electron gun of one embodiment of the present application.

[0036] Figure 2 The working principle schematic diagram of the semiconductor device of one embodiment of the present application.

[0037] Explanation of reference signs:

[0038] 10 - cathode;

[0039] 20 - grid;

[0040] 30 - anode part;

[0041] 31 - first anode plate; 32 - second anode plate; 33 - third anode plate; 34 - fourth anode plate;

[0042] 40 - electron beam;

[0043] 41 - cross spot; 42 - beam spot;

[0044] 50 - electrostatic lens;

[0045] 60 - magnetic lens;

[0046] 61 - coil; 62 - pole piece;

[0047] 100 - electron gun;

[0048] 200 - target material;

[0049] 300 - monochromator;

[0050] 400 - sample. DETAILED DESCRIPTION

[0051] The exemplary embodiments of the present application are described herein below with reference to the accompanying drawings. It is to be understood that the specific description is merely for the purpose of illustration and does not exhaust all possible ways of implementing the present application, nor is it intended to limit the scope of the present application.

[0052] An electron gun is a device for generating, accelerating and converging high-energy density electron beam, which can emit an electron beam with certain energy, current, speed and angle. Electron guns are widely used in the fields of electron tubes, electron microscopes, display screens (fluorescent screens), radars and photoelectron spectrometers, etc. An electron emission device is used for generating and accelerating an electron beam, and is one of the core components of an electron gun.

[0053] Embodiment One

[0054] As shown in Figure 1 Embodiment One of the present application provides a multi-anode electron emission device (hereinafter, sometimes referred to as "emission device"), which can include a cathode 10, a grid 20 and an anode part 30, wherein the anode part 30 can include a plurality of anode plates. By arranging a plurality of anode plates, the electric field formed by the plurality of anode plates together can preliminarily focus the electron beam 40 (which can be further focused by the focusing system of the electron gun later), reduce the divergence of the electron beam, and thus improve the performance of the electron gun, and also enable the design of the focusing system of the electron gun to be more flexible.

[0055] Specifically, the cathode 10 is used for generating electrons, i.e., the cathode 10 is the emitter of electrons. Exemplarily, the cathode 10 can be a cathode filament (e.g., a tungsten filament), which can form and release a large number of hot electrons outward on the surface after being heated by electricity. The grid 20, also known as the control grid, is the control electrode of the electrons, which is relatively close to the cathode 10. The grid 20 can be connected to a negative voltage, and by changing the voltage between the grid 20 and the cathode 10, the electric field intensity on the surface of the cathode 10 can be changed, thereby controlling whether the cathode 10 emits an electron current and controlling the density of the electron current.

[0056] The anode part 30 is the accelerating electrode and the extraction electrode of the electrons, and the anode part 30 can be applied with a relatively high voltage for attracting the electron current released by the cathode 10. The acceleration and attraction of the electron current by the anode part 30 can form an electron beam 40 with a relatively high speed. The cathode 10, the grid 20 and the anode part 30 can be arranged at a certain distance apart, and the axial directions of the cathode 10, the grid 20 and the anode part 30 can coincide.

[0057] The anode part 30 can include a plurality (here, "a plurality" can include two or more) of anode plates. The plurality of anode plates can be arranged along the axial direction of the multi-anode electron emission device to accelerate the electrons in sequence. Exemplarily, as shown in Figure 1As shown, the anode part 30 can include four anode plates, i.e., the anode part 30 can include a first anode plate 31, a second anode plate 32, a third anode plate 33, and a fourth anode plate 34. In some application scenarios, the anode part is provided with four anode plates, which can better form an electric field capable of focusing the electron beam. The plurality of anode plates can be arranged along the advancement direction of the electron beam 40 (or the axial direction of the multi-anode electron emission device), and the plurality of anode plates can be arranged at a certain distance. The specific interval can be set according to the actual electric field needs of the electron gun.

[0058] The voltage of the plurality of anode plates can be sequentially increased from upstream to downstream (the voltage of the anode plate relatively far from the cathode is greater than the voltage of the anode plate relatively close to the cathode), so as to gradually increase the speed of the electron beam 40. Preferably, the voltage difference between adjacent anode plates can be the same, i.e., the voltage increase between adjacent anode plates can be the same, so as to improve the uniformity of the electric field. It can be understood that the voltage difference between adjacent anode plates can also be in a multiplication relationship, etc. In some examples, the voltage of the plurality of anode plates can also be irregularly increased. The voltage of the plurality of anode plates can be sequentially increased, and can be set according to the actual application needs of the electron gun. Compared with only providing a single anode plate, the anode part with a plurality of anode plates has higher adjustment freedom, so as to form a suitable electric field according to the actual use scenario, thereby effectively improving the divergence problem of the electron beam.

[0059] The plurality of anode plates included in the anode part 30 can collectively form an electric field structure capable of focusing the electron beam 40. When the electron beam 40 passes through the anode part, the electric field formed by the anode part 30 can gradually focus the electron beam 40 (i.e., make the electron beam 40 gradually approach the axial direction of the electron gun), thereby forming a cross spot 41 with a smaller diameter (better quality), and ultimately forming a beam spot 42 with a smaller diameter, i.e., achieving the performance improvement of the electron gun.

[0060] Preferably, the anode part 30 can adopt a flat plate anode. Compared with a cylindrical anode, a conical anode, and other anode structures, the flat plate anode has better uniformity of the formed electric field, has smaller electric field distortion, and can reduce the divergence of the electron beam 40 caused by the non-uniformity of the anode electric field. The flat plate anode can be formed with holes for passing electrons.

[0061] Preferably, the grid 20 can be connected to negative voltage direct current, and the anode part 30 can be connected to positive voltage direct current. Connecting the grid and the anode part to direct current is more suitable for adjusting the electron beam, and this structure is simple and can save the occupied space of the electron emission device.

[0062] Preferably, the plurality of anode plates can have the same size, and the plurality of anode plates can be equally spaced. The plurality of anode plates having the same size and being equally spaced can form a more uniform uniform electric field, and can enable the electron beam to be better focused. In addition, using anode plates of the same size can also make the structure of the multi-anode electron emission device simpler, reduce manufacturing costs, and save the occupied space of the device.

[0063] The multi-anode electron emission device provided in the embodiment can be particularly suitable for a micro-focal spot (focal spot also referred to as beam spot, micro-focal spot refers to a focal spot of micron level or smaller) electron gun, which can form a very fine electron beam of micron level (or smaller). The micro-focal spot electron gun can be further applied to a high-precision electron emission device (semiconductor device with high resolution or high control precision).

[0064] Embodiment Two

[0065] Based on the above embodiments, as shown in Figure 1 Embodiment Two of the present application provides an electron gun, in particular a micro-focal spot electron gun for forming a very fine electron beam. The electron gun can generate, accelerate and converge a high-energy density electron beam, and the electron gun can include the multi-anode electron emission device in Embodiment One and a focusing system. The focusing system can be arranged downstream of the emission device, and is used to further focus the preliminarily focused electron beam generated by the emission device. The further focused electron beam can finally form a beam spot with good quality at the receiving end.

[0066] As shown in Figure 1 The focusing system can include an electrostatic lens 50 and / or a magnetic lens 60. The number of the electrostatic lens 50 and / or the magnetic lens 60 can be one or more.

[0067] The electrostatic lens 50 can use the electrostatic field generated by the charged conductor to focus and image the electron beam 40. The electrostatic lens in the embodiment can be a film hole lens, a single lens or an immersion lens, and the specific type of the electrostatic lens is not limited in the embodiment.

[0068] The magnetic lens 60, also referred to as an electromagnetic lens, can converge charged particles through an axisymmetric magnetic field, and further focus the electron beam 40. The magnetic lens 60 can include a coil 61 and a pole shoe 62. The coil 61 can form an axisymmetric magnetic field after being energized, and the pole shoe 62 can at least partially wrap the coil 61 to improve the strength and uniformity of the magnetic field, thereby improving the convergence ability of the magnetic lens 60.

[0069] The electron gun provided in the embodiment can be particularly used in devices such as X-ray photoelectron spectrometer (XPS).

[0070] Embodiment Three

[0071] Based on the above embodiments, the application discloses a semiconductor device, which can be an X-ray source system, such as Figure 2 As shown in the figure, the X-ray source system can include an electron gun 100 and a monochromator 300. The electron gun 100 can be the electron gun provided in the above embodiments, and the electron beam formed by the electron gun 100 can bombard the target material 200. The target material 200 can be a metal or a metal compound (especially a high-atomic-number metal such as tungsten, copper, etc.), and the target material 200 can generate X-rays after the electron beam bombards the target material 200. The monochromator 300 can be a device for filtering or adjusting X-rays, which can allow X-rays of a specific wavelength (single wavelength) to pass through. The X-rays adjusted by the monochromator 300 can further irradiate the sample 400, and the sample 400 can diffract, absorb, scatter, or stimulatedly emit X-ray fluorescence under the irradiation of the X-rays.

[0072] Next, the partial beneficial effects of the embodiments of the application are briefly described.

[0073] The multi-anode electron emission device, the electron gun and the semiconductor device provided by the application can improve the anode electric field distortion by providing an anode part including a plurality of anode plates, form an electric field capable of preliminarily focusing the electron beam, improve the divergence problem of the electron beam, and improve the quality of the cross spot. The anode part provides a plurality of anode plates, which can flexibly adjust the voltage difference between the anode plates according to the actual use requirements of the electron gun, form an electric field more in line with the use requirements of the electron gun, and improve the electron beam focusing effect. Further, due to the improvement of the focusing effect of the electron beam of the emission device, the design of the focusing system of the electron gun can also be more flexible, and the overall performance of the electron gun is ultimately improved. The semiconductor device provided by the application can apply the electron beam generated by the above-mentioned electron gun to bombard X-rays, and the X-rays can irradiate the sample after being adjusted by the monochromator.

[0074] It can be understood that, in the application, the number of components or members is not particularly limited, and the number can be one or more, and the plurality herein refers to two or more. For the case where the number of components or members is described as a specific number, such as two, three, four, etc. in the drawings and / or the description, the specific number is generally exemplary rather than limiting, and can be understood as a plurality, i.e. two or more, but this does not mean that the application excludes the case of one.

[0075] It should be understood that the above-described embodiments are merely exemplary and not intended to limit the present application. Various modifications and alterations of the described embodiments can be made by those skilled in the art within the scope of the present application without departing from the scope of the present application. The above-described embodiments are merely preferred embodiments of the present application, and the present application should be understood to include any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application.

Claims

1. A multi-anode electron emission device for a microfocal spot electron gun, characterized in that, Includes a cathode (10), a grid (20), and an anode (30). The cathode (10) is used to release electrons. The anode portion (30) is disposed downstream of the cathode (10), and the anode portion (30) and the cathode (10) are spaced apart to attract and accelerate electrons released by the cathode (10) to form an electron beam. The gate (20) is disposed between the cathode (10) and the anode (30). The gate (20) is connected to a negative voltage to regulate the electric field strength on the surface of the cathode (10). Spacing is formed between the gate (20) and the cathode (10) and between the gate (20) and the anode portion (30). The anode section (30) includes a plurality of anode plates, which are spaced apart and the voltage of the plurality of anode plates increases sequentially from upstream to downstream. The plurality of anode plates are used to form an electric field for focusing the electron beam.

2. The multi-anode electron emitting device according to claim 1, characterized in that, The multiple anode plates are arranged along the axial direction of the multi-anode electron emission device.

3. The multi-anode electron emitting device according to claim 1 or 2, characterized in that, The gate (20) is connected to negative DC power, and the anode (30) is connected to positive DC power.

4. The multi-anode electron emitting device according to any one of claims 1 to 3, characterized in that, The voltage difference between adjacent anode plates is equal.

5. The multi-anode electron emitting device according to any one of claims 1 to 4, characterized in that, The anode plate is a flat anode with holes for electrons to pass through.

6. The multi-anode electron emitting device according to any one of claims 1 to 5, characterized in that, The anode section (30) includes a first anode plate (31), a second anode plate (32), a third anode plate (33), and a fourth anode plate (34).

7. The multi-anode electron emitting device according to any one of claims 1 to 6, characterized in that, The plurality of anode plates are of the same size, and the spacing between the plurality of anode plates is equal.

8. An electron gun, characterized in that, include: The multi-anode electron emission device according to any one of claims 1 to 7; And a focusing system, which is located downstream of the multi-anode electron emitting device, for focusing the electron beam formed by the multi-anode electron emitting device.

9. The electron gun according to claim 8, characterized in that, The focusing system includes an electrostatic lens (50) and / or a magnetic lens (60).

10. The electron gun according to claim 9, characterized in that, The number of the electrostatic lens (50) and / or the magnetic lens (60) is multiple.

11. The electron gun according to any one of claims 8 to 10, characterized in that, The focusing system includes a magnetic lens (60), which includes a coil (61) and a pole piece (62), the pole piece (62) at least partially enclosing the coil (61).

12. A semiconductor device, characterized in that, It includes an electron gun as described in any one of claims 8-11, and a monochromator disposed downstream of the electron gun, the monochromator being used to filter X-rays.

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