Particle energy band-pass device, electron energy analyzer and photoelectron spectrometer
Through the particle energy bandpass device combining electrostatic field and magnetic field, the problem of low energy resolution in the prior art is solved, and high-efficiency energy segment screening and particle flux improvement are achieved, which is suitable for a variety of application scenarios.
Patent Information
- Application Number
- CN202420441285.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-07
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-03-07
AI Technical Summary
The existing particle energy analyzers combine magnetic field deflection and slits, and have poor energy resolution, cannot provide high energy resolution, and have high requirements for the energy resolution of the incident ion beam and cannot be re-screened.
Using a combination of electrostatic field and magnetic field, a particle energy bandpass device is designed to screen the particle energy segment through the deflection cavity, transmitter, reflector and adjustable magnetic field, without setting a slit and adding reflection channels to Improve particle flux and detection efficiency, and combine it with lens systems and detector systems to achieve a wide range of functions of particle energy analyzers.
It realizes efficient energy segment screening, improves particle flux and detection efficiency, simplifies the device structure, reduces costs, and is compatible with various lens systems and detectors, suitable for a variety of application scenarios.
Smart Images
Figure CN222168326U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of charged particle optical equipment, in particular to a particle energy bandpass device, an electron energy analyzer and a photoelectron spectrometer. Background Art
[0002] A particle energy bandpass device is a device that can select particles with a certain energy range from a particle beam with multiple energies. This selection can set both an upper limit and a lower limit. It is also commonly called a particle energy analyzer. Existing particle energy analyzer technologies include time-of-flight method, electrostatic field reflection method, electrostatic field deflection method, magnetic field deflection method, etc.
[0003] Taking LEEM technology as an example, an electron beam with as much energy as possible is injected from top to bottom. When the electron beam passes through the intermediate magnetic field, it is deflected, irradiates the sample on the right, and then returns. The returning electron beam is deflected downward and received by the detector to form a detection signal. When the electron beam is deflected to the right or downward, a slit is set at the exit. Because electron beams of different energies have different deflection radii, a certain energy bandpass selection is performed when passing through the slit.
[0004] However, the above-mentioned technologies have the following defects: (1) the combination of magnetic field deflection and slits has poor energy resolution and cannot provide high energy resolution; (2) the energy resolution of the incident ion beam is high and re-screening is not possible. Utility Model Content
[0005] In order to solve the deficiencies in the prior art, the present application proposes a particle energy bandpass device, which realizes the screening of energy segments by combining electrostatic fields and magnetic fields. It does not require the setting of slits and has a large receiving angle, which can greatly improve the particle flux and detection efficiency. The particle energy bandpass device designed by the utility model can also be combined with electronic optics-related components such as particle lens systems and detector systems to obtain a particle energy analyzer with wide functions.
[0006] The technical solution adopted by the utility model is as follows:
[0007] A particle energy bandpass device, comprising:
[0008] At least 1 deflection cavity;
[0009] The deflection cavity is provided with at least one incident channel, and a charged transmitter is provided in the incident channel. The charged particle beam enters from the incident channel and enters the deflection cavity after passing through the transmitter.
[0010] The deflection cavity has a magnetic field, and the charged particle beam in the deflection cavity is deflected in the magnetic field; the strength of the magnetic field is adjustable; the direction of the magnetic field can also be adjusted according to the electrical characteristics of the charged particles;
[0011] The deflection cavity is provided with at least one reflection channel, and the deflected charged particle beam enters the reflection channel; a charged reflector is provided in the reflection channel, and the charged particle beam enters the magnetic field after being screened and reflected by the reflector;
[0012] The deflection cavity is provided with at least one exit channel, and the charged particle beam is emitted from the exit channel.
[0013] Furthermore, by adding reflection channels and reflectors, the charged particle beam is screened and reflected multiple times in the deflection cavity.
[0014] Furthermore, the deflection cavity is connected to another one or more deflection cavities through a reflection channel and / or an exit channel.
[0015] Furthermore, according to the screening requirements of the energy range, the voltages of the transmitter in the incident channel and the reflector in the reflection channel are set respectively.
[0016] Furthermore, the transmitter and reflector both adopt a transmitter-like structure.
[0017] Furthermore, the mesh structures are all made of gold-plated copper mesh.
[0018] Furthermore, a transmitter is provided in the exit channel.
[0019] An electron energy analyzer, based on the above-mentioned particle energy bandpass device, is provided with at least one lens system on any one or more of the incident channel, the reflection channel and the exit channel; and a charged particle detector is provided at the exit port of the exit channel.
[0020] Furthermore, lens systems with specific functions are selected at different channels according to functional requirements; the functional requirements include angular resolution, spatial resolution or high throughput.
[0021] A photoelectron spectrometer is provided with a light source on the basis of the above-mentioned particle energy bandpass device, and the photoelectrons are excited from the sample by the added light source and enter the incident channel.
[0022] Beneficial effects of the utility model:
[0023] (1) It has an energy bandpass function, which can realize the screening of energy segments by combining electrostatic field and magnetic field. In addition, by scanning the voltage of each component, it can also realize the measurement of electron beam energy spectrum.
[0024] (2) The incident particles and the screened outgoing particles are on the same axis, which greatly facilitates the calibration and layout of the detector. In addition, the outgoing direction of the outgoing particles can be changed as needed, making the layout of the detector more flexible.
[0025] (3) No slit is required at the entrance of the incident particles, thereby achieving a large receiving angle and greatly improving the particle flux and detection efficiency.
[0026] (4) The simplest structure of the device consists of only four components: an entrance transmitter, a reflector, an exit transmitter, and a magnetic field deflection cavity. This makes the layout of the entire device simple, highly universal, and low-cost.
[0027] (5) The energy bandpass structure of the utility model is compatible with various lens systems currently used in the field of energy analyzers, including electrostatic lenses, magnetic lenses; active lenses or passive lenses; axisymmetric types, non-axis-symmetrical types, etc. It has strong compatibility and can be applied to various application scenarios.
[0028] (6) The utility model can make the energy bandpass, energy analyzer, and energy spectrum analyzer compact and small, which is particularly suitable for some miniaturized application scenarios.
[0029] (7) The utility model can be matched with a variety of commonly used 0-dimensional, 1-dimensional, 2-dimensional and other detectors, and has strong compatibility. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1 This is a schematic diagram of the structure of a particle energy bandpass device proposed by the utility model;
[0031] Figure 2 This is a structural schematic diagram of an electronic energy analyzer proposed by the utility model;
[0032] Figure 3 This is a schematic diagram of the structure of a photoelectron spectrometer proposed by the utility model;
[0033] In the figure, 1, incident side transmitter, 2, reflector, 3, magnetic field, 4, exit side transmitter, 5, deflection cavity, 6a-6j are all electron beams, 7, sample, 10, first lens system, 11, second lens system, 12, third lens system, 13, fourth lens system, 14, electron detector, 21, light source. DETAILED DESCRIPTION
[0034] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.
[0035] Example 1
[0036] The utility model designs a particle energy bandpass device, the structure of which is as follows: Figure 1As shown, a deflection cavity 5 is included, and a plurality of channels are arranged outside the deflection cavity 5. The plurality of channels can be used as incident channels, reflection channels, exit channels or spare channels.
[0037] An incident side transmitter 1 is provided in the incident channel, and the incident side transmitter 1 is perpendicular to the incident channel, and a negative voltage is applied to the incident side transmitter 1. The sample 7 is located outside the incident side transmitter 1, so the grounded sample 7 emits an electron beam 6a, which can reach the incident side transmitter 1. Since a certain negative voltage is applied to the incident side transmitter 1, electrons with lower energy will be reflected to form an electron beam 6b. Electrons with higher energy than the incident side transmitter 1 will pass through the incident side transmitter 1 to form an electron beam 6c, and then the electron beam 6c enters the deflection cavity 5.
[0038] The deflection cavity 5 has a magnetic field 3, and the magnetic field 3 causes the electron beam entering the deflection cavity 5 from the incident channel to produce the first deflection. After the first deflection, the electron beam moves toward the reflection channel. A reflector 2 is arranged in the reflection channel, and the reflector 2 is vertically arranged in the reflection channel, and the reflector 2 is also loaded with a negative voltage. Since the reflector 2 is loaded with a certain negative voltage. The electron beam with higher energy will directly pass through the reflector 2 to form an electron beam 6f, which is absorbed by the cavity wall. The electrons with lower energy are reflected by the reflector 2 to form an electron beam 6g. The electron beam 6g enters the deflection cavity 5 again, and is deflected for the second time under the action of the magnetic field 3 to form an electron beam 6h. After the second deflection, the electron beam leaves the magnetic field to form an electron beam 6i. The electron beam 6i moves toward the exit channel, and an exit side transmitter 4 is arranged in the exit channel. The electron beam 6i will pass through the transmitter 4 to form a final electron beam 6j.
[0039] In the above design, the upper and lower limits of energy are cut off under the joint action of the incident side transmissor 1 in the incident channel, the reflector 2 in the reflection channel and the magnetic field 3 in the deflection cavity 5.
[0040] In the above design, the angles between the channels outside the deflection cavity 5 can be designed to be various angles such as 60°, 90° or 120°.
[0041] In the above process description, only the electron beam is reflected once as an example. However, in actual applications, multiple reflections can be set, that is, the electron beam after the second deflection also enters the reflection channel, and a second reflection occurs under the action of the reflector. Similarly, a third reflection channel and reflector can also be set. After multiple reflections, the electron beam is finally emitted from the exit channel.
[0042] More specifically, the incident-side transmissor 1 , the reflector 2 , and the exit-side transmissor 4 are all made of gold-plated copper mesh, and the transmittance can reach 95%.
[0043] More specifically, the incident-side transmissor 1 , the reflector 2 , and the exit-side transmissor 4 all adopt a flat-plate mesh structure.
[0044] More specifically, a coil is arranged around the deflection cavity 5, and the coil provides a magnetic field 3 inside the deflection cavity 5 when energized; the intensity of the magnetic field can be adjusted by adjusting the current in the coil.
[0045] More specifically, the deflection cavity 4 is made of a non-magnetic material, such as metal such as aluminum, copper or titanium.
[0046] Example 2
[0047] In the above design, at least one channel on the first layer of deflection cavities is connected to the second layer of deflection cavities, or at least one channel is sequentially connected to multiple layers of deflection cavities; therefore, the electron beam emitted from the channel can enter the next layer of deflection cavities.
[0048] The second deflection cavity also has a reflection channel, an output channel, a reflector, a transmitter, and other designs. A magnetic field is also set in the second deflection cavity to deflect the electron beam in the second deflection cavity. Therefore, if the first deflection cavity is connected to multiple deflection cavities, a multi-layer bandpass and different output designs can be realized. Figure 1 For example, the reflection channel on the left side of the deflection cavity 5 can be connected to another deflection cavity 5 (referred to as the second layer of deflection cavity), so the electron beam with higher energy passing through the reflector 2 can enter the second layer of deflection cavity, and the energy range screening can continue in the second layer of deflection cavity. The exit channel above the deflection cavity 5 can also be connected to another deflection cavity 5 (referred to as the third layer of deflection cavity), and the electron beam emitted through the exit side transmitter 4 can enter the third layer of deflection cavity, and the energy range screening can continue; similarly, deflection cavities 5 can be added on the basis of the second layer of deflection cavity and the third layer of deflection cavity.
[0049] Example 3
[0050] Based on the particle energy bandpass device proposed in embodiment 1 or 2, the utility model also proposes an electron energy analyzer, whose structure is as follows: Figure 2 As shown. A particle energy bandpass device proposed in Example 1 or 2 is combined with a particle lens system, a detector system and other electronic optical related components to form a particle energy analyzer with extensive functions. More specifically, at least one first-level lens system is set at any one or more channels of the incident channel, reflection channel and exit channel of a particle energy bandpass device proposed in Example 1 or 2, and the lens system is composed of multiple lenses arranged coaxially. The lens system can be set according to functional requirements, and the functional requirements include different characteristics such as angle resolution, spatial resolution or high throughput.
[0051] Attach Figure 2For example, a first lens system 10 is added between the incident port and the sample 7, a second lens system 11 is added between the incident side transmissometer 1 and the deflection cavity 5, a third lens system 12 is added between the deflection cavity 5 and the reflector 2, a fourth lens system 13 is added between the deflection cavity 5 and the exit side transmissometer 4, and an electron detector 14 is added behind the exit side transmissometer 4.
[0052] The first lens system 10 transmits the electrons emitted from the sample 7 to the incident side transmitter 1. The transmission of electrons in the first lens system 10 can be different characteristics such as angle resolution, spatial resolution, high flux, etc. according to the requirements, which are controlled by the lens system. The incident electron beam 6a, after being screened by the utility model patent, forms an outgoing electron beam 6i. An electron detector 14 is set at the exit port of the exit channel to measure the electrons emitted through the exit port. Therefore, the outgoing electron beam 6i is finally measured by the electron detector 14 to obtain the intensity or image information of the energy segment screened by the energy band pass device of the utility model.
[0053] More specifically, the electron detector 14 can be an electron multiplication detector, a DLD detector, an MCP-phosphor screen structure detector, or other various instruments that can achieve similar functions.
[0054] More specifically, the present embodiment is an electron energy analyzer with a relatively complete structure, which can be used in various application scenarios such as electron spectrometers, such as XPS, ARPES, k-ARPES, PEEM, AES, etc.
[0055] More specifically, the present invention can achieve precise control of the entire path of the electron beam to the electron detector 14 through the combination of the lens system and the functional setting of the lens system.
[0056] Example 4
[0057] Based on the design of a particle energy bandpass device shown in the above embodiment 3, the present invention obtains a new photoelectron spectrometer structure by adding a light source 21. The light source 21 can excite photoelectrons from the sample 7, and the excited photoelectrons 6a enter the electronic energy spectrum analyzer of the present invention for detection, and the electronic structure of the material can be obtained.
[0058] More specifically, the light source 21 is disposed on the incident channel side.
[0059] More specifically, the light source 21 may be a laser light source, a plasma light source, a synchrotron radiation light source or other various forms of light sources.
[0060] The above embodiments are only used to illustrate the design ideas and features of the utility model, and their purpose is to enable those skilled in the art to understand the content of the utility model and implement it accordingly. The protection scope of the utility model is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design ideas disclosed by the utility model are within the protection scope of the utility model.
Claims
1. A particle energy bandpass device, characterized in that: include: at least one deflection chamber (5); The deflection cavity (5) is provided with at least one incident channel, and a charged transmitter is provided in the incident channel. The charged particle beam enters from the incident channel and enters the deflection cavity (5) after passing through the transmitter. The deflection cavity (5) has a magnetic field (3) in it, and the charged particle beam in the deflection cavity (5) is deflected in the magnetic field (3); The deflection cavity (5) is provided with at least one reflection channel, and the deflected charged particle beam enters the reflection channel; a charged reflector is provided in the reflection channel, and the charged particle beam enters the magnetic field (3) after being screened and reflected by the reflector; The deflection cavity (5) is provided with at least one exit channel, and the charged particle beam is emitted from the exit channel.
2. A particle energy bandpass device according to claim 1, characterized in that: By adding reflection channels and reflectors, the charged particle beam is screened and reflected multiple times in the deflection cavity (5).
3. A particle energy bandpass device according to claim 1, characterized in that: The deflection cavity (5) is connected to another or more deflection cavities (5) via a reflection channel and / or an exit channel.
4. A particle energy bandpass device according to claim 1, 2 or 3, characterized in that: According to the screening requirements of the energy range, the voltages of the transmitter in the incident channel and the reflector in the reflection channel are set respectively.
5. A particle energy bandpass device according to claim 4, characterized in that: The transmissive device and the reflective device are both transmissive devices.
6. A particle energy bandpass device according to claim 5, characterized in that: The transmissive devices are all made of gold-plated copper mesh.
7. A particle energy bandpass device according to claim 5, characterized in that: A transmitter is arranged in the exit channel.
8. An electron energy analyzer, characterized in that: A particle energy bandpass device according to claim 4, wherein at least one lens system is provided on any one or more of the incident channel, the reflection channel and the exit channel; and an electron detector (14) is provided at the exit of the exit channel.
9. An electron energy analyzer according to claim 8, characterized in that: Lens systems with specific functions are selected at different channels according to functional requirements; the functional requirements include angle resolution, spatial resolution or high throughput.
10. A photoelectron spectrometer, characterized in that: Based on the particle energy bandpass device described in claim 1, a light source (21) is provided, and the light source (21) is added to excite photoelectrons from the sample (7) to enter the incident channel.