CN118150619A - Apparatus and method for surface analysis using low energy inert gas ion scattering - Google Patents
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- 229910052729 chemical element Inorganic materials 0.000 description 3
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Abstract
The invention relates to a device and a method for carrying out surface analysis by utilizing low-energy inert gas ion scattering, comprising the following steps: generating a mixed ion probe beam composed of a plurality of inert gas ions; the mixed ion probe beam irradiates the surface of a sample to be detected, one part of ions are back scattered on atoms on the surface of the sample to be detected to generate back scattered ions, the other part of ions penetrate the surface of the sample to be detected and collide and cascade with the atoms of the sample to be detected to cause sputtering and secondary ion emission of the atoms of the sample to be detected to generate secondary sputtered ion flow; carrying out energy analysis on the back scattering ions and the secondary sputtering ion flow to obtain an energy spectrum of the ions; the energy separated ions are mass analyzed to form an energy-mass separation spectrum. The method comprises the steps of bombarding the surface of a sample with an ion beam containing a plurality of inert gas ions by combining an advanced low-energy ion scattering technology with a mass spectrometry technology to generate back scattered ions and secondary sputtered ions, and carrying out energy spectrum analysis and additional mass spectrometry on the ions.
Description
Technical Field
The invention relates to the field of analytical instrument manufacturing, in particular to a device and a method for carrying out surface analysis by utilizing low-energy inert gas ion scattering.
Background
In TOF-SIMS (Time of Flight Secondary Ion Mass Spectrometry, time-of-flight secondary ion mass spectrometry), the sample surface is bombarded with a cluster ion beam, and sputtering (resolving) produces secondary ions. Inert gas modification of the formed, component mixed gas cluster ion beam can increase the intensity of resolving molecular ions in time-of-flight secondary ion mass spectrometry compared to high energy gas cluster beam bombardment. For strong Low-energy inert gas ion scattering and secondary ion and mass separation, a currently existing device is LEIS (Low-Energy Ion Scattering, low-energy particle scattering spectrometer), and an ion beam containing various inert gas ions (He+, ne+, ar+) is taken as a detection beam (primary ion beam), so that the back scattered ions are tested and analyzed. LEIS is composed of inert gas injection system, ion source (ion gun), high-vacuum sample stage, ion detection system, related power supply, spectrum acquisition and decomposition system. The main disadvantage of this solution is that it is not possible to distinguish between the backscattered ions and the sputtered ions in the signal, thus reducing the elemental sensitivity of the LEIS method and sometimes even recording the backscattered ion signal.
Disclosure of Invention
Aiming at the technical problems in the prior art, the invention provides a device for carrying out surface analysis by utilizing low-energy inert gas ion scattering, which carries out additional mass spectrometry on energy separation signals (namely energy separated ions) of backscattered ions and secondarily sputtered ions of different inert gas probe beams, and improves the test efficiency and the running speed of spectrometer equipment.
According to a first aspect of the present invention there is provided an apparatus for surface analysis using low energy inert gas ion scattering, comprising: the ion probe beam generation module, the test platform and the analysis module;
The ion probe beam generation module is used for generating a mixed ion probe beam composed of a plurality of inert gas ions;
the test platform is used for placing a sample to be tested;
The mixed ion probe beam irradiates the surface of the sample to be detected, one part of ions in the mixed ion probe beam are back scattered on surface atoms of the sample to be detected to generate back scattered ions, the other part of ions penetrate the surface of the sample to be detected and collide and cascade with the atoms of the sample to be detected to cause sputtering and secondary ion emission of the atoms of the sample to be detected to generate secondary sputtered ion flow;
The analysis module comprises: an electrostatic energy analyzer and a mass analyzer;
the back scattered ions and the secondary sputtering ion flow enter the electrostatic energy analyzer to be analyzed to obtain the energy spectrum of the ions; the mass analyzer analyzes the energy separated ions to form an energy-mass separation spectrum.
On the basis of the technical scheme, the invention can also make the following improvements.
Optionally, the ion probe beam generating module includes: the ion source comprises an air storage tank, an ion source and a power supply; the air storage tank and the power supply are connected with the ion source;
The gas storage tank stores a plurality of injected inert gases;
After a plurality of inert gases in the gas storage tank flow into the ion source, the ion source ionizes various inert gas atoms under the drive of the power supply to generate various ions, and the ions are accelerated to set energy E 0 to obtain a focused positive ion beam as the mixed ion probe beam.
As an optional working substance, the plurality of inert gases includes: at least two of helium, neon, argon, and argon-containing neon.
When the inert gases are helium, neon and argon, the ionization voltages of the inert gases are 24.6V, 21.6V and 15.8V respectively.
The test platform comprises: a vacuum chamber and a high vacuum mechanical manipulator;
the platform for placing the sample to be tested and the high-vacuum mechanical manipulator are both arranged in the vacuum cavity, and the high-vacuum mechanical manipulator is used for controlling the position of the platform.
After the back-scattered ions and the secondary sputtered ion stream enter the energy analyzer, the energy spectrum of all the analyzed ions is formed between 0 and a set energy E 0;
the mass analyzer separates the energy separated ions according to the M/q value thereof to form the energy-mass separation spectrum; m and q are the mass and charge of the ion, respectively.
Optionally, the apparatus further comprises an automatic control and signal acquisition system for recording the energy-mass separation spectrum.
According to a second aspect of the present invention there is provided a method of surface analysis using low energy inert gas ion scattering, comprising:
step 1, generating a mixed ion probe beam composed of a plurality of inert gas ions;
Step 2, the mixed ion probe beam irradiates the surface of the sample to be detected, one part of ions in the mixed ion probe beam are back scattered on surface atoms of the sample to be detected to generate back scattered ions, the other part of ions penetrate the surface of the sample to be detected and collide and cascade with the atoms of the sample to be detected to cause sputtering and secondary ion emission of the atoms of the sample to be detected to generate secondary sputtered ion flow;
Step 3, carrying out energy analysis on the back scattering ions and the secondary sputtering ion flow to obtain an energy spectrum of ions; the energy separated ions are mass analyzed to form an energy-mass separation spectrum.
Optionally, the generating the hybrid ion probe beam in the step 1 includes:
The method comprises the steps of setting a connected gas storage tank and an ion source, injecting various inert gases into the gas storage tank, ionizing various inert gas atoms by the ion source to generate various ions after the various inert gases in the gas storage tank flow into the ion source, and accelerating the ions to set energy E 0 to obtain a focused positive ion beam which is the mixed ion probe beam.
Optionally, the plurality of inert gases includes: at least two of helium, neon, argon, and argon-containing neon;
when the inert gases are helium, neon and argon, the inert gases are input into the ion source through the gas storage tank, and the ionization voltages of the inert gases are 24.6V, 21.6V and 15.8V respectively.
The invention provides a device and a method for carrying out surface analysis by utilizing low-energy inert gas ion scattering, which adopts an advanced low-energy ion scattering (LEIS) technology to carry out element component test analysis on a material surface layer. The ion beam containing a plurality of inert gas ions (He +、Ne+、Ar+) is used as a probe beam or a primary ion beam, the mass spectrum analysis is carried out on the back scattered ions and the secondary sputtered ions, the high surface sensitivity and the high mass spectrum resolution are achieved, meanwhile, the chemical element distribution in a large range is detected and recorded, and the detection efficiency and the running speed of the instrument are improved. The low-energy ion scattering (LEIS) analysis instrument consists of a vacuum chamber, an ion source and a detector, wherein the working substance of the ion source is inert gas (He, ne and Ar), and the ion source is fed into a gas storage tank. The detection system consists of an electrostatic energy analyzer and a mass filter. The low-energy ion scattering (LEIS) surface analysis method is characterized in that: and bombarding the sample to be detected by using a plurality of inert gas ions (He +、Ne+、Ar+), detecting back scattered ions and secondary sputtered ions, and performing energy-mass spectrum test analysis.
Drawings
FIG. 1 is a schematic diagram of the relationship between mass spectrum resolution ΔM and surface atomic mass M;
FIG. 2 is a schematic view of the energy distribution (energy spectrum) obtained when the aluminum surface is irradiated with Ne+ ions having an energy of 3 keV;
FIG. 3 is a block diagram of an apparatus for surface analysis using low energy inert gas ion scattering according to an embodiment of the present invention;
FIG. 4 is a depth profile spectrum of a cobalt oxide on indium thin film according to an embodiment of the present invention;
in the drawings, the list of components represented by the various numbers is as follows:
In the figure: 1. the device comprises a vacuum cavity, 2, a vacuum pump, 3, an ion source, 4, an air storage tank, 5, an ion source power supply, 6, a sample to be tested, 7, a high vacuum mechanical manipulator (including a heater), 8, a mixed ion probe beam, 9, an electrostatic energy analyzer (a spherical deflector), 10, an energy analyzer power supply, 11, a mass analyzer, 12, an ion detector (a secondary electron multiplier), 13, a mass analyzer power supply, 14, an automatic control and signal acquisition system.
Detailed Description
The principles and features of the present invention are described below with reference to the drawings, the examples are illustrated for the purpose of illustrating the invention and are not to be construed as limiting the scope of the invention.
LEIS is an energy analysis of an inert gas ion based on kinetic energy E 0 and mass M 0, the incident inert gas ion being scattered at an angle θ from atoms of mass M on top of the sample surface. Ions penetrating deep into the surface undergo multiple collisions and are almost completely neutralized (lose charge), and do not contribute to the scattered ion yield.
Using the laws of conservation of energy and conservation of momentum, the energy E of the backscattered primary ions can be calculated using the formula:
Where the relative mass coefficient α=m/m0 >1, which means that the primary scattered ions must be lighter than the surface atoms. From equation (1), the mass of the surface atoms M can be determined as:
Thus, surface element analysis can be performed using the energy analysis result of the back-scattered ions. In this case, the neutralization of the ions entering the interior of the material takes place, the contribution of primary ions scattered from deeper layers being negligible. However, there are also low energy secondary ions in the recorded signal, i.e. surface ionized atoms sputtered during the interaction of the primary ion beam with the sample surface. The mass spectral resolution of the LEIS method can also be determined by equation (2). Mass resolution is the mass range (Δm=m2-M1) within which ion signals scattered from surface atoms of mass M2 and M1, respectively, can be separated at a given maximum signal intensity (e.g., 10%).
Where (E/ΔE) a is the relative resolution of the energy analyzer at the selected maximum signal intensity and Δθ is the input acceptance of the energy analyzer, i.e., the range of scattering angles at which the backscattered ions are recorded.
Fig. 1 is a schematic diagram showing a relationship between the mass spectrum resolution Δm and the surface atomic mass M, fig. 1 shows a relationship between the mass spectrum resolution Δm and the surface atomic mass M of primary ions such as 4he+, 20ne+ and 40ar+ and the like, and a calculation formula is (3). Typical parameters of LEIS spectrometers used are: the scattering angle θ=120°, the angular resolution Δθ=1.5°, the energy resolution (E/Δe) a=0.03 (10% of the maximum signal intensity). Fig. 1 shows the correlation of Δm (M), which can provide mass spectral resolution of Δm=2amu for backscattered ions 4He+、20 ne+ and 40 ar+ in the range of 5-26, 21-55amu and 41-78amu, respectively, at a level of 10% of maximum signal intensity.
Fig. 2 is a schematic view of the energy distribution (energy spectrum) obtained when the aluminum surface is irradiated with ne+ ions having an energy of 3keV, and fig. 2 shows an example in which Ne ions of E 0 =3 keV (scattering angle θ=120° and incident angle ψ=60°) are used to bombard the aluminum surface, and the energy spectra of sputtered 27 al+ ions and backscattered 20 ne+ ions are measured. Wherein the red line is the energy spectrum of the secondarily sputtered Al ions and the black line is the energy spectrum of the backscattered Ne ions. It can be seen that the signal of the sputtered ion is much higher than that of the backscattered ion, so LEIS analysis cannot be performed in this case.
Fig. 3 is a block diagram of an apparatus for performing surface analysis by using low-energy inert gas ion scattering according to an embodiment of the present invention, and as can be seen from fig. 3, the apparatus includes: an ion probe beam generation module, a test platform and an analysis module.
The ion probe beam generating module is used to generate a mixed ion probe beam 8 composed of a plurality of inert gas ions.
The test platform is used for placing a sample 6 to be tested.
The mixed ion probe beam 8 irradiates the surface of the sample 6 to be detected, bombards the surface of the sample, interacts with atoms on the surface, and part of ions in the mixed ion probe beam 8 are back scattered on the atoms on the surface of the sample 6 to be detected to generate back scattered ions, positive charges of the back scattered ions are kept, and the other part of ions penetrate the surface of the sample 6 to be detected and collide and cascade with the atoms of the sample 6 to be detected to cause sputtering and secondary ion emission of the atoms of the sample 6 to be detected to generate secondary sputtered ion flow.
The analysis module comprises: an electrostatic energy analyzer 9 and a mass analyzer 11.
The back scattered ions and the secondary sputtered ions flow into an electrostatic energy analyzer 9 for analysis to obtain the energy spectrum of the ions; the mass analyzer 11 analyzes the energy separated ions to form an energy-mass separation spectrum.
The method for carrying out surface analysis by utilizing low-energy inert gas ion scattering provided by the invention combines an advanced low-energy ion scattering (LEIS) technology with a mass spectrometry technology, bombards the surface of a sample by using ion beams containing a plurality of inert gas ions (He+, ne+, ar+) to generate back scattered ions and secondary sputtered ions, carries out energy spectrum analysis and additional mass spectrometry on the ions, expands the measurement range of chemical elements in the material, has higher element sensitivity and mass spectrometry resolution than a known prototype LEIS spectrometer, carries out depth profile analysis at a higher speed, and can be used for analyzing the element composition of the surface layer of the material and devices (including a two-dimensional structure) to develop and test an analysis instrument.
Example 1
Example 1 provided by the present invention is an example of an apparatus for performing surface analysis by using low energy inert gas ion scattering, and as can be seen in fig. 3, the apparatus includes:
the device comprises: an ion probe beam generation module, a test platform and an analysis module.
The ion probe beam generating module is used to generate a mixed ion probe beam 8 composed of a plurality of inert gas ions.
In one possible embodiment, the ion probe beam generating module comprises: a gas storage tank 4, an ion source 3 and an ion source power supply 5; the gas holder 4 and the ion source power supply 5 are connected to the ion source 3.
In particular, the ion source 3 comprises an ionizer, an electrostatic lens for transmitting and focusing the ion beam, and an electrostatic deflector.
The gas tank 4 stores a plurality of inert gases to be injected.
After the inert gases in the gas storage tank 4 flow into the ion source 3, the ion source 3 ionizes the inert gas atoms to generate various ions under the drive of the ion source power supply 5, and accelerates the ions to a set energy E 0 (usually less than 3 keV) to obtain a focused positive ion beam as a mixed ion probe beam 8.
In one possible embodiment, the plurality of inert gases includes: at least two of helium, neon, argon, and argon-containing neon.
Helium, neon, argon or argon-containing neon is injected into the gas tank 4 according to the range of the elements analyzed and the requirements of the depth profile analysis.
In one possible embodiment, when the plurality of inert gases are helium, neon and argon, the ionization voltages are 24.6V, 21.6V and 15.8V, respectively, which are input to the ion source 3.
Since the subsequent ionization process of the inert gas in the ion source 3 is performed by the electron beam, the ionization potentials of He, ne, and Ar are considered to be 24.6V, 21.6V, and 15.8V, respectively, when selecting the partial pressure of the gas reservoir 4.
The test platform is used for placing a sample 6 to be tested.
In one possible embodiment, the test platform comprises: a vacuum chamber 1 and a high vacuum mechanical manipulator 7.
A stage on which a sample 6 to be measured is placed, and a high vacuum mechanical manipulator (with a heater) 7 are provided in the vacuum chamber 1, the high vacuum mechanical manipulator 7 being used to precisely control the position of the stage.
In a specific implementation, the vacuum cavity 1 is communicated with the outside through the vacuum pump 2, and the vacuum pump 2 is used for vacuumizing the vacuum cavity 1 after the sample 6 to be measured is placed.
The mixed ion probe beam 8 irradiates the surface of the sample 6 to be detected, bombards the surface of the sample, interacts with atoms on the surface, and part of ions in the mixed ion probe beam 8 are back scattered on the atoms on the surface of the sample 6 to be detected to generate back scattered ions, positive charges of the back scattered ions are kept, and the other part of ions penetrate the surface of the sample 6 to be detected and collide and cascade with the atoms of the sample 6 to be detected to cause sputtering and secondary ion emission of the atoms of the sample 6 to be detected to generate secondary sputtered ion flow.
In practice, the ion probe beam in the ion source 3 has no mass separation means, which allows multiple inert gas ions (He+, ne+, ar+) to irradiate the sample surface simultaneously. The sputtering rate increases with the mass of the probe ions, which means that the ar+ ions sputter (etch) the sample surface the best.
The analysis module comprises: an electrostatic energy analyzer 9 and a mass analyzer 11.
The back scattered ions and the secondary sputtered ions flow into an electrostatic energy analyzer 9 for analysis to obtain the energy spectrum of the ions; the mass analyzer 11 analyzes the energy separated ions to form an energy-mass separation spectrum. The electrostatic energy analyzer is driven in operation by an energy analyzer power supply 10.
In one possible embodiment, after the back-scattered ions and the stream of sputtered ions enter the energy analyzer, the energy spectrum (energy distribution dN/dE) of all analyzed ions is formed between 0 and a set energy E 0.
The mass analyzer 11 separates the energy separated ions according to their M/q values to form an energy-mass separation spectrum; m and q are the mass and charge of the ion, respectively.
In a possible implementation, the apparatus further comprises an automatic control and signal acquisition system 14, wherein the automatic control and signal acquisition system 14 is configured to record the energy-mass separation spectrum, and the data obtained by the analysis module is collected and recorded by the ion detector 12 and the automatic control and signal acquisition system 14. The mass analyzer 11 uses a quadrupole mass filter, the ion detector 12 can use a secondary electron multiplier, and the detection system is driven to operate by a mass analyzer power supply 13.
The invention aims to perform sputtering (ion etching) on the surface of a tested sample at the same time of carrying out LEIS energy spectrum test and depth profile analysis. In the present invention, the energy resolution of the ion beam is improved by changing the energy analysis mode of the ion beam. Specifically, the invention uses advanced mass spectrometry technology to carry out mass spectrometry on the back scattered ions and the secondary sputtered ions. By measuring the mass and energy distribution of these ions, the elemental composition of the sample surface can be more accurately determined. The ion source generates an ion beam containing a plurality of inert gas ions, and the ion beam is accelerated to a certain energy by a high-voltage electric field. The sample stage is moved by a stepper motor and a computer controller and controls the angle and position of incidence of the ion beam. Mass analyzers are used to measure the mass and energy distribution of backscattered ions and sputtered ions.
The method and the device can obtain the element composition analysis with high resolution and high sensitivity, and the technology has important significance for analyzing the element composition of the material and the surface of the device, and can be widely applied to the fields of material science, semiconductor material and the device, surface physics, chemistry and the like.
Example 2
Example 2 provided by the present invention is an example of a method for performing surface analysis by using low energy inert gas ion scattering, and as can be seen in fig. 3, the method includes:
Step 1, generating a mixed ion probe beam composed of a plurality of inert gas ions.
In one possible implementation, the process of generating the hybrid ion probe beam in step 1 includes:
The method comprises the steps of arranging a connected gas storage tank and an ion source, injecting various inert gases into the gas storage tank, ionizing various inert gas atoms by the ion source to generate various ions after the various inert gases in the gas storage tank flow into the ion source, and accelerating the ions to set energy E 0 (usually less than 3 keV) to obtain a focused positive ion beam which is a mixed ion probe beam.
In one possible embodiment, the plurality of inert gases includes: at least two of helium, neon, argon, and argon-containing neon.
When helium, neon and argon are used as the inert gases, the ionization voltages are 24.6V, 21.6V and 15.8V respectively.
And 2, irradiating the surface of the sample to be detected by the mixed ion probe beam, bombarding the surface of the sample, and interacting with atoms on the surface, wherein part of ions in the mixed ion probe beam are back scattered on the atoms on the surface of the sample to be detected to generate back scattered ions, the positive charges of the back scattered ions are kept, and the other part of ions penetrate through the surface of the sample to be detected and collide and cascade with the atoms of the sample to be detected to cause sputtering and secondary ion emission of the atoms of the sample to be detected to generate secondary sputtered ion flow.
In practice, the ion probe beam in the ion source has no mass separation device, which allows multiple inert gas ions (He+, ne+, ar+) to irradiate the sample surface simultaneously. The sputtering rate increases with the mass of the probe ions, which means that the ar+ ions sputter (etch) the sample surface the best.
Step 3, carrying out energy analysis on the back scattering ions and the secondary sputtering ion flow to obtain an energy spectrum of the ions; the energy separated ions are mass analyzed to form an energy-mass separation spectrum.
It can be understood that, in the method for performing surface analysis by using low-energy inert gas ion scattering according to the present invention, corresponding to the apparatus for performing surface analysis by using low-energy inert gas ion scattering provided in the foregoing embodiments, the relevant technical features of the method for performing surface analysis by using low-energy inert gas ion scattering may refer to the relevant technical features of the apparatus for performing surface analysis by using low-energy inert gas ion scattering, which will not be described herein.
Example 3
Example 3 provided by the present invention is a specific application example of an apparatus and a method for performing surface analysis by using low-energy inert gas ion scattering, an experiment is performed by using a cobalt oxide film deposited on the surface of an indium material, and In the example provided In fig. 4, an elemental composition test and a depth profile analysis of C oOx/In are performed by using advanced LEIS. The probe ions are He + and Ne + with energies of E 0 = 1keV, which are scattered by atoms In the sample, including He + and Ne + ions scattered from oxygen (He +/O), cobalt (Ne +/Co) and indium (Ne +/In), and are sputtered with the ions In the sample by the incident he+ and ne+ ions, i.e. to produce secondarily sputtered 59 co+ and 115 in+ ions.
When the probe ions were e0=1kev He + and Ne +, back-scattered ions (He +/O,Ne+/Co and Ne +/In) and secondary sputtered ions (59 Co +,115In+) were generated, and energy-mass analysis was performed to obtain the depth profile spectrum of fig. 4.
It can be seen that the device and the method for performing surface analysis by using low-energy inert gas ion scattering provided by the embodiment of the invention have higher working efficiency, because in the test process, the surface of the sample is simultaneously subjected to multiple inert gas (such as He + and Ne +) ions, and continuous energy analysis and mass analysis are performed on the back scattered ions and the secondary sputtered ions, so that the device and the method have higher element sensitivity and mass spectrum resolution, expand the test analysis range of element components, and can perform depth profile analysis at higher running speed.
The embodiment of the invention provides a device and a method for carrying out surface analysis by utilizing low-energy inert gas ion scattering, which adopts an advanced low-energy ion scattering (LEIS) technology to carry out element component test analysis on a material surface layer. The ion beam containing a plurality of inert gas ions (He +、Ne+、Ar+) is used as a probe beam or a primary ion beam, the mass spectrum analysis is carried out on the back scattered ions and the secondary sputtered ions, the high surface sensitivity and the high mass spectrum resolution are achieved, meanwhile, the chemical element distribution in a large range is detected and recorded, and the detection efficiency and the running speed of the instrument are improved. The low-energy ion scattering (LEIS) analysis instrument consists of a vacuum chamber, an ion source and a detector, wherein the working substance of the ion source is inert gas (He, ne and Ar), and the ion source is fed into a gas storage tank. The detection system consists of an electrostatic energy analyzer and a mass filter. The low-energy ion scattering (LEIS) surface analysis method is characterized in that: and bombarding the sample to be detected by using a plurality of inert gas ions (He +、Ne+、Ar+), detecting back scattered ions and secondary sputtered ions, and performing energy-mass spectrum test analysis.
In the foregoing embodiments, the descriptions of the embodiments are focused on, and for those portions of one embodiment that are not described in detail, reference may be made to the related descriptions of other embodiments.
It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (10)
1. An apparatus for surface analysis using low energy inert gas ion scattering, the apparatus comprising: the ion probe beam generation module, the test platform and the analysis module;
The ion probe beam generation module is used for generating a mixed ion probe beam composed of a plurality of inert gas ions;
the test platform is used for placing a sample to be tested;
The mixed ion probe beam irradiates the surface of the sample to be detected, one part of ions in the mixed ion probe beam are back scattered on surface atoms of the sample to be detected to generate back scattered ions, the other part of ions penetrate the surface of the sample to be detected and collide and cascade with the atoms of the sample to be detected to cause sputtering and secondary ion emission of the atoms of the sample to be detected to generate secondary sputtered ion flow;
The analysis module comprises: an electrostatic energy analyzer and a mass analyzer;
the back scattered ions and the secondary sputtering ion flow enter the electrostatic energy analyzer to be analyzed to obtain the energy spectrum of the ions; the mass analyzer analyzes the energy separated ions to form an energy-mass separation spectrum.
2. The apparatus of claim 1, wherein the ion probe beam generating module comprises: the ion source comprises an air storage tank, an ion source and a power supply; the air storage tank and the power supply are connected with the ion source;
The gas storage tank stores a plurality of injected inert gases;
After a plurality of inert gases in the gas storage tank flow into the ion source, the ion source ionizes various inert gas atoms under the drive of the power supply to generate various ions, and the ions are accelerated to set energy E 0 to obtain a focused positive ion beam as the mixed ion probe beam.
3. The apparatus of claim 2, wherein the plurality of inert gases comprises: at least two of helium, neon, argon, and argon-containing neon.
4. The apparatus of claim 1, wherein when the plurality of inert gases are helium, neon and argon, ionization voltages thereof are 24.6V, 21.6V and 15.8V, respectively, as gases inputted to the gas storage tank and the subsequent ion source.
5. The apparatus of claim 1, wherein the test platform comprises: a vacuum chamber and a high vacuum mechanical manipulator;
the platform for placing the sample to be tested and the high-vacuum mechanical manipulator are both arranged in the vacuum cavity, and the high-vacuum mechanical manipulator is used for controlling the position of the platform.
6. The apparatus of claim 1, wherein after the back-scattered ions and the stream of sputtered ions enter the energy analyzer, the energy spectrum of all analyzed ions is formed between 0 and a set energy E 0;
the mass analyzer separates the energy separated ions according to the M/q value thereof to form the energy-mass separation spectrum; m and q are the mass and charge of the ion, respectively.
7. The apparatus of claim 1, further comprising an automated control and signal acquisition system for recording the energy-mass separation spectrum.
8. A method for surface analysis using low energy inert gas ion scattering, the method comprising:
step 1, generating a mixed ion probe beam composed of a plurality of inert gas ions;
Step 2, the mixed ion probe beam irradiates the surface of the sample to be detected, one part of ions in the mixed ion probe beam are back scattered on surface atoms of the sample to be detected to generate back scattered ions, the other part of ions penetrate the surface of the sample to be detected and collide and cascade with the atoms of the sample to be detected to cause sputtering and secondary ion emission of the atoms of the sample to be detected to generate secondary sputtered ion flow;
Step 3, carrying out energy analysis on the back scattering ions and the secondary sputtering ion flow to obtain an energy spectrum of ions; the energy separated ions are mass analyzed to form an energy-mass separation spectrum.
9. The method of claim 8, wherein generating the hybrid ion probe beam in step 1 comprises:
The method comprises the steps of setting a connected gas storage tank and an ion source, injecting various inert gases into the gas storage tank, ionizing various inert gas atoms by the ion source to generate various ions after the various inert gases in the gas storage tank flow into the ion source, and accelerating the ions to set energy E 0 to obtain a focused positive ion beam which is the mixed ion probe beam.
10. The method of claim 9, wherein the plurality of inert gases comprises: at least two of helium, neon, argon, and argon-containing neon;
When the inert gases are helium, neon and argon, the ionization voltages of the three gas elements are 24.6V, 21.6V and 15.8V respectively, and the inert gases are input into the gas storage tank and the ion source.
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| Publication Number | Publication Date |
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| CN118150619A true CN118150619A (en) | 2024-06-07 |
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