KR100429830B1 - X-ray electronic spectrum analyzer - Google Patents

Abstract

PURPOSE: An X-ray electronic spectrum analyzer is provided to make various experiments at any time and any places by mounting a plurality of units having different functions in one system and to secure reliable experimental results without an EXAFS(Extended X-ray Absorption Fine Structure) equipment. CONSTITUTION: An X-ray electronic spectrum analyzer is composed of an X-ray generator(11) for generating X-rays; an X-ray pull-in converger(13) for converging the X-rays from the X-ray generator; a monochromator(14) for converting the X-rays passing through the X-ray pull-in converger into a monochromatic X-ray of a short wavelength; an X-ray delivery converger(16) for converging and delivering the monochromatic X-ray sent from the monochromator; an X-ray monitoring unit(17) for monitoring the monochromatic X-ray passing through the X-ray delivery converger; an X-ray photon detector(18) for detecting a photon of the X-ray passing through the X-ray monitoring unit and incident to a test piece; an electron detector(19) for detecting the electron emitted from the test piece by the X-ray passing through the X-ray monitoring unit and incident to the test piece; an X-ray detector(20) for detecting the X-ray reflected and emitted from the test piece and the X-ray transmitting the test piece by the X-ray passing through the X-ray monitoring unit and incident to the test piece; and a control unit for controlling each component and progressing a signal.

Description

X-ray electron spectroscopy

The present invention relates to an X-ray electron spectroscopy apparatus, and more particularly, to an X-ray electron spectroscopy apparatus capable of quantitatively evaluating component composition, electron and atomic structure, and physical properties of materials and materials.

Apparatuses and devices related to X-ray analysis, which have been commercialized or published in the literature, have approximately the following characteristics.

1) Extended X-ray absorption fine structure (EXAFS) devices for general laboratories operate only in the air, and therefore can only measure transmission X-ray absorption or fluorescent X-rays.

2) The range of monochromatic X-rays is small, limiting the types of elements that can be analyzed. It is usually possible in the range of calcium (Ca, atomic number 20) -bromine (Br, atomic number 35) on the basis of the K-line absorption of the element, usually in the 4keV-14keV region. If you want to use a large area of energy, you have to move to another area and use different equipment.

3) Use the goniometer of the theta-2theta powder X-ray diffractometer as it is, and fix the analysis sample. Instead, use a heavy X-ray generating tube or X-ray generator. Move.

4) By using a berillium window between the X-ray tube and the vacuum chamber, all of the less energy X-rays (soft X-rays) are absorbed and cannot be measured in the energy region less than 2 keV.

5) The method of moving each part on the Roland circumference uses two or three atmospheric stepping motors and a belted drive mechanism. Therefore, the error due to the movement of the component is large.

6) The diffraction crystal of the monochromator for producing monochromatic light is a flat crystal, which has poor energy resolution.

7) Due to the lack of X-ray light, it takes a long time to obtain the EXAFS spectrum.

8) There is only one EXAFS experimental measurement function, and it is difficult to make the most of the equipment component functions.

9) Because the geometric arrangement of the detector and the sample is simple, it is difficult to perform angularly resolved geometric experiments, and it is not possible to simultaneously measure the transmission absorption, the fluorescent X-ray, and the X-ray induced emission electron quantity.

10) In the case of the radiation device, since the size of the monochromatic light beam irradiated onto the surface of the specimen is large, it is difficult to analyze small specimens or small portions.

11) In some device designs, the reflected beam of the monochromator does not focus on the specimen, but focuses on the X-ray monitor or emission slit, causing the beam to be irradiated onto the specimen.

The present invention has been made in view of the above-mentioned problems, and X-ray electron spectroscopy can be performed qualitatively and quantitatively to evaluate component composition, electron and atomic structure, and physical properties of materials and materials using a single device system. The object is to provide a device.

1 is a schematic block diagram of an X-ray electron spectrometer according to the present invention.

Figure 2 is a front view showing a vacuum chamber and the control unit of the X-ray electron spectroscopy apparatus according to the present invention.

Figure 3 is a plan view showing a vacuum chamber and the control unit of the X-ray electron spectroscopy apparatus according to the present invention.

Figure 4 is a cross-sectional view showing the internal structure of the vacuum chamber of the X-ray electron spectroscopy apparatus according to the present invention.

5 is a device configuration of the specimen detection unit and the monochromator of the X-ray electron spectroscopy apparatus according to the present invention.

Figure 6 is a schematic diagram of a vacuum exhaust system of the X-ray electron spectroscopy apparatus according to the present invention.

7 is a schematic configuration diagram of a control and signal detection system of the X-ray electron spectroscopy apparatus according to the present invention.

8 is a schematic diagram illustrating an X-ray focusing principle in the X-ray electron spectroscopy apparatus according to the present invention.

Figure 9a is a geometrical arrangement in the high energy region for explaining the energy scanning method of the X-ray electron spectroscopy apparatus according to the present invention.

Figure 9b is a geometrical arrangement diagram in the middle energy region for explaining the energy scanning method of the X-ray electron spectroscopy apparatus according to the present invention.

Figure 9c is a geometrical optical layout of the low energy region for explaining the energy scanning method of the X-ray electron spectroscopy apparatus according to the present invention.

10 is a view showing a spectroscopic X-ray optical system and necessary parameters of the X-ray electron spectroscopy apparatus according to the present invention.

11 is a view showing a Ce-K absorption edge electron emission spectrum obtained from a CeO ₂ sample by an X-ray electron spectroscopy apparatus according to the present invention.

12 is a view showing a spectrum obtained in the diffraction panel of the Ge (111) monochromator by the X-ray electron spectroscopy apparatus according to the present invention.

13 is a view showing a spectrum obtained in the Cu-L line by the X-ray electron spectroscopy apparatus according to the present invention.

14 is a diagram showing an X-ray absorption spectrum obtained from a Cu thin film (13 μm) sample by an X-ray electron spectroscopy apparatus according to the present invention.

FIG. 15 is a diagram showing an EXAFS spectrum obtained from a Cu thin film (8 μm) sample by an X-ray electron spectroscopy apparatus according to the present invention. FIG.

FIG. 16 is a diagram showing an electron emission spectrum obtained from a TiN (thickness 110 nm) / Si sample by an X-ray electron spectroscopy apparatus according to the present invention. FIG.

FIG. 17 is a view showing a fluorescence emission spectrum obtained from a TiN (thickness 110 nm) / Si sample by an X-ray electron spectroscopy apparatus according to the present invention. FIG.

18 is a view showing an electron emission spectrum measured while varying the angle between the Ge (111) crystal plane and the incident X-rays by the X-ray electron spectroscopy apparatus according to the present invention.

19 is a view showing the Cu-Kα1, Cu-Kα2 characteristic spectrum measured by the optical energy in 0.2eV step by the X-ray electron spectroscopy apparatus according to the present invention.

20 is a view showing the rocking curve of the InP single crystal (004) plane of the optical energy is fixed to the Cu-Kα1 line by the X-ray electron spectroscopy apparatus according to the present invention, and repeatedly measured twice.

<Explanation of symbols for the main parts of the drawings>

11 ... X-ray generator 12 ... Vacuum chamber

12s ... vacuum chamber support 12t ... vacuum chamber support table

13 ... X-ray incoming converging unit 14 ... Monochromator

15 ... Specimen detector 16 ... X-ray transmitter

17 ... X-ray monitoring device 18 ... X-ray photon detector

19 ... Electronic detector 20,20 '... X-ray detector

21 Control unit 22 Vacuum gauge control unit / relay board

23 ... detector controller 24 ... stepping motor controller

25 ... DC power supply 26,27 ... 1st, 2nd turbo molecular pump controller

41,42 ... Linear guide 43 ... Roland sector

61,62 ... Vacuum bellows tube 63 ... Gate valve

64,67 ... thermocouple gauge 65, 66 ... ion gauge

68,69 ... Vent Valve 70,71 ... Shutoff Valve

72 ... rotary pump 73, 74 ... molecular turbopump

81 ... Control Computer 82 ... PC / ISA Bus Expansion Box

83 ... X-Ray Generator / Controller 87 ... Stepping Motor Controller

88 ... Detection system 89 ... Voice message system

In order to achieve the above object, the X-ray electron spectroscopy apparatus according to the present invention,

An X-ray generator for generating X-rays; An X-ray incoming converging device for converging X-rays generated from the X-ray generator; A monochromator for converting the X-rays passing through the X-ray incoming converging unit into a monochromatic X-ray having a short wavelength; An X-ray transmitting converging unit for converging and transmitting the monochromatic X-rays transmitted from the monochromator; An X-ray monitoring apparatus for monitoring a monochromatic X-ray having passed through the X-ray transmitting convergence unit; An X-ray photon detector for detecting photons of X-rays incident on any specimen via the X-ray monitoring apparatus; An electron detector for detecting electrons emitted from the specimen by X-rays incident on any specimen via the X-ray monitoring device; An X-ray detector for detecting X-rays reflected and emitted from the specimens and X-rays passing through the specimens by X-rays incident on any specimen through the X-ray monitoring apparatus; And a control unit for control and signal processing of the respective components.

Here, in particular, the components other than the X-ray generator and the control unit may be vacuumed to prevent energy being absorbed by the intermediate blocking material until the X-ray generated from the X-ray generator reaches the specimen. It is desirable to be installed inside the chamber.

According to the present invention, since a plurality of units each having a different function in one device system is provided, there is an advantage that the user can perform the desired experiment without the constraints of time and space. In addition, reliable test results can be obtained at any time without the use of the EXAFS facility attached to the radiation accelerator device, and it saves extra effort and time for assigning beam time for use of the accelerator device. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic system configuration diagram of an X-ray electron spectroscopy apparatus according to the present invention.

Referring to FIG. 1, an X-ray electron spectroscopic analyzer according to the present invention includes an X-ray generator 11 for generating X-rays, and an X-ray generated from the X-ray generator 11. X-ray inlet converging unit 13 for converging the X-rays, monochromator 14 for converting the X-rays passing through the X-ray inlet converging unit 13 into monochromatic X-rays of short wavelength, and X-ray transmission converging unit 16 for converging and transmitting the monochromatic X-rays transmitted from the monochromator 14, and for monitoring the monochromatic X-rays passing through the X-ray transmission converging unit 16 An X-ray monitoring device 17, an X-ray photon detector 18 for detecting photons of X-rays incident on an arbitrary specimen S via the X-ray monitoring device 17, and the X An electron detector 19 and the X-ray monitoring device for detecting electrons emitted from the specimen S by X-rays incident on the specimen S via a ray monitoring device 17 ( An X-ray detector 20 for detecting X-rays reflected and emitted from the specimen S and X-rays passing through the specimen S by the X-rays incident on the specimen S via 17). ). Reference numeral 15 denotes a specimen detection section as components that actually detect the specimen S by X-rays.

Here, the X-ray generator 11 is used in particular an X-ray generator for generating a white X-ray, a collimator (collimator) is used as the X-ray inlet and outgoing convergence (13, 16) do. In addition, a gas proportional detector is used as the X-ray photon detector 18, a channel -tron is used as the X-ray electron detector 19, and an X-ray detector 20 is used. ), A scintillation detector is used.

Each of the above components is installed in the vacuum chamber 12 except for the X-ray generator 11 as shown in FIGS. 2 and 3. In addition, a control unit 21 is provided adjacent to the vacuum chamber 12 for control and signal processing of the respective components. Here, the control unit 21 includes a vacuum gauge control unit and a relay board 22, a detection device controller 23 for controlling each detection device, and a plurality of steppings to enable mechanical movement of each detection device. ) A stepping motor controller 24 for controlling a motor (not shown in the vacuum chamber), a DC power supply 25 for supplying DC power required for the system, and first and second turbomolecular pumps. It consists of the controllers 26 and 27. In addition, the control unit 21 is connected to a computer (not shown) again. Thus, the apparatus and the device control unit of the present invention are entirely operated by a computer. Of course, in such a computer, a specific operating program for operating the apparatus and the device control unit is prepared and stored in advance by the user. In Figs. 2 and 3, reference numeral 12s denotes a vacuum chamber support, and 12t denotes a vacuum chamber support table, respectively.

4 illustrates an internal structure of the vacuum chamber 12, in which the device elements of the photon energy scanning mechanism, the monochromator 14, and the specimen detector 15 are called Roland circles. (Rowland circle) is arranged to have a correlation. That is, the two linear guides 41 and 42 are supported and fixed to the wall of the vacuum chamber 12, and the circular Roland sector 43 having a radius of 600 mm is opposite to the linear guides 41 and 42, respectively. It is fixed. At this time, both ends of the Roland sector 43 can move freely along the linear guides 41 and 42, so that the Roland sector 43 can be located at any point of the linear guides 41 and 42. . The Roland sector 43 is supported on the bottom surface of the vacuum chamber 12. In order to allow the Roland sector 43 and the body of the specimen detection unit 15 to be smoothly slid and moved, friction with the bottom surface is 50 kg or more. Sapphire plates are attached to the bottom of the three Roland sector supports in order to reduce the pressure. And the bottom surface of the vacuum chamber 12 is processed so that flatness may be within 1 micron with respect to a floor whole surface.

FIG. 5 shows a specimen detector 15 and a monochromator 14 installed in the Roland sector 43, in which the specimen S is rotatable 360 degrees about its vertical axis. In addition, the detectors 19, 20, 20 ′ can also be arranged in a very wide angle range. Since six crystals having different crystal plane spacings can be mounted and used simultaneously in the six-side drum revolver of the monochromator 14, monochromatic light can be obtained in a very wide energy region. For example, lithium fluoride 200, lithium fluoride 422, Ge (germanium) 111, Ge (111) f, PET (Pentaerythritol) (002) with six crystals having different crystal plane spacings. Potassium hydrogen phthalate (KHP) (100) is used. Here, Ge (111) f is a planar crystal, and the rest are Johansson-shaped crystals, and the surface of each crystal is precisely machined to a radius of curvature R with respect to the Roland radius R, and is in the X-ray beam direction. Is bent at a 2R radius. This Johansson-shaped structure of the crystal surface increases the amount of light of the monochromatic light by more than 10 times, and improves the energy resolution of the monochromatic light.

6 shows a vacuum system for maintaining the vacuum of the vacuum chamber 12, in which the vacuum bellows tube 61 and the gate are formed so that the X-ray generator 11 and the vacuum chamber 12 are one vacuum space. It is connected to the valve (63). By doing so, since X-rays emitted from the X-ray generator 11 do not have a material blocking them in the middle until they reach the specimen, the energy of the X-rays is not absorbed. In Figure 6, reference numeral 62 is a vacuum bellows tube, 64, 67 is a thermocouple gauge, 65, 66 is an ion gauge, 68, 69 is a vent valve, 70, 71 is a shutoff valve, 72 is a rotary pump, 73, 74 is a molecular turbo Each pump is shown.

7 shows a control and signal detection system of an X-ray electron spectrometer according to the present invention, the X-ray generator / controller 83 is a specific program (eg, STAR program) for operating the system ( 81s) is electrically connected directly to the control computer 81 stored therein, and receives a predetermined control signal from the control computer 81 to operate. In addition, a vacuum gauge control signal 84, a rotary pump and a vacuum valve control signal 85, and a molecular turbo pump control are provided from a PC / ISA bus expansion box 82 connecting the control computer 81 and each unit. The signal 86 and the like are transmitted, and accordingly, various operations by the operation units inside the vacuum chamber 12 occur. That is, the rotation of the crystal plane of the monochromator 14 and the drum by driving two stepping motors, linear movement for energy scanning by driving one stepping motor each, Roland sector scanning, exit slit Width adjustment, aiming head rotation, specimen rotation, etc. occur. The position control of the X-ray monitor detector, the operation of the channeltron electron detector and the gas proportional type X-ray detector are performed respectively, and the operation control of the scintillation X-ray detector outside the vacuum chamber 12 is also performed. In the above operation and control, rotation of the crystal plane and drum of the monochromator 14, linear movement for energy scanning, Roland sector scanning, exit slit width adjustment, aiming head rotation, specimen rotation, and the like are stepping motors. It is made by the controller 87, and the position control of the X-ray monitor detector, the operation control of the channeltron electron detector and the gas proportional X-ray detector are performed by the stepping motor controller 87 and the detection system 88. . Here, the voice message system 89 is provided as shown to show whether the device operates normally not only by the video signal and data displayed on the computer monitor but also by the sound by generating a specific sound according to the operation state of the device. do.

Then, the operation of the X-ray electron spectrometer according to the present invention having the configuration as described above will be described.

The apparatus of the present invention employs the Johansson X-ray condensing method, which has the best condensing efficiency and excellent characteristics to focus and reflect the X-ray beams. Therefore, as shown in Fig. 8, all three beams L1, L2, L3 emitted from the X-ray light source (X-ray generating position of the X-ray generator) 91s are all the same with respect to the crystal plane. It has a reflection angle θ, which means that it can theoretically have the same focal size even at the focal position 91f. At this time, scanning for the X-ray photon energy E (keV) means changing the angle θ according to Bragg's law, which can be expressed as follows. have.

2dsinθ = n12.396 / E

At the same time, the surface of the crystal plane is also continuously positioned at the Roland radius R. In the present invention, the X-ray light source is fixed spatially, the crystal-monochromator is fixed on the Roland sector of radius R, and the Roland sector always moves its circumference in line with the light source. And, the specimen located where the reflected beam is in focus can move along the Roland sector. In addition, the discharge slit is attached to the platform of the specimen.

The energy scanning method of the X-ray electron spectroscopy apparatus according to the present invention under the above conditions and conditions will be described with reference to FIGS. 9A, 9B, and 9C.

9a to 9c show a geometrical optical arrangement illustrating the energy scanning method of the X-ray electron spectroscopy apparatus according to the present invention, FIG. 9a is a geometrical optical layout in the high energy region, and FIG. 9b is an intermediate energy region. FIG. 9C is a geometrical optical layout in the low energy region. FIG.

By the geometrical optical arrangements shown in Figs. 9A, 9B and 9C, the spectra as shown in Figs. 11, 12 and 13 are obtained, respectively. FIG. 11 is a spectrum obtained by a channeltron electron detector for the amount of electron emission corresponding to the X-ray absorption of Ce atoms from CeO ₂ powder samples in the high energy region where the monochromatic light energy is around 40.5 keV. FIG. 12 is a spectra obtained in a medium energy region of 6 keV, and a scintillation detector for Mo-Kα1, Mo-Kα2, and Mo-Kβ1 characteristic X-rays emitted from the molybdenum (Mo) anode of the X-ray generator X-rays of the light source are analyzed. FIG. 13 is an X-ray spectrum of characteristic X-rays Lα, Lβ peaks of a copper (Cu) anode in the low energy region of 0.9 keV with a channeltron electron detector.

Therefore, the following three movements must be satisfied to scan for light energy. That is, the Roland sector must be linearly moving along the direction in which the X-ray beam is emitted, the sample and slit platforms must move along the circumference of the Roland sector, and the platform must rotate relative to the focal point. FIG. 10 shows the geometrical optical placement in the intermediate energy region in relation to the required parameters in relation to the above fulfillment conditions.

As shown in FIG. 10, one of the requirements for energy scanning is that the centerline of the incident beam and the centerline of the reflected beam should be symmetrical with respect to the normal of the crystal plane. The distance L from the point where the two center lines meet to the light source can be expressed as follows.

L = 2 Rsinθ

At this time, the rotation angle of the platform with respect to the center of the crystal surface is 2θ, and the aiming turn angle of the platform with respect to the focal point is π / 2-θ. The most important basic characteristics of the spectrometer of the present invention can be said to be the monochromatized photon flux and the resolution of the light energy. In this case, the energy resolution ΔE may be defined by the dispersion of the diffraction angle θ, and may be expressed by Equation 1 as follows.

ΔE = (Ecosθ) Δθ

Here, there are three factors influencing the energy resolution, and the diffraction angle dispersion, Δθ, is expressed as Δθ = Δθ ₁ + Δθ ₂ + Δθ ₃ as the sum of these three elements. In addition, the geometrical major aberration occurs when the size of the beam projected in parallel with the filament of the X-ray generator is not a mathematical point but has a finite size. For example, when the filament has a focal size of 10 mm x 0.5 mm and a take-off angle of 6 degrees, the projection focal width F is 0.05 mm. Under these geometric conditions, the following diffraction angle dispersion Δθ ₁ is made.

Δθ ₁ = F / 4Rsinθ

The width of the crystal and the crystal angle ω formed by the light source determine the amount of light flux. To obtain a larger amount of light, the crystal angle ω must be larger. However, the actual resolution ΔE of the X-ray light energy of the Johansson type spectrometer is affected by the crystal angle (ω). This is because it is difficult to obtain a complete crystal free from defects in the size of the crystal used in the monochromator 14. The arc length of the optical crystal usually employed in the spectrometer is between 20 mm and 50 mm. The smaller this crystal length, the better the energy resolution is obtained. In addition, the vertical length of the crystal also affects the resolution and the amount of light as shown in Equation 5 below. The smaller the vertical length of the crystal, the better the resolution, but the smaller the amount of light. Another parameter that determines the amount of light is the Roland radius (R). The smaller the radius R, the larger the crystal angle with respect to the parallel length of a given crystal, so that a larger amount of light can be obtained. On the other hand, as shown in Equation 5 below, the resolution is inversely proportional to the radius. Therefore, obtaining a large amount of light conflicts with obtaining a good resolution. Most of the Johansson-type spectrometers reported to date have a radius of 280 mm to 450 mm, and it was not reported until the late 1980s that a Roland radius (R) of about 500 mm was reported. This is because in a real device, the Roland radius (R) of more than 450 mm is due to the challenge of qualitatively new levels of technology and design problems in order to make the spectroscopic characteristics satisfactory. In the apparatus of the present invention, it is possible to satisfactorily obtain spectroscopic characteristics while maintaining a Roland radius of 600 mm.

The influence of the vertical divergence may be expressed as in Equation 5 below.

Δθ ₂ = (H ² / 32R ² ) secθcosecθ

Here, H represents the vertical size of the electron beam that forms on the anode of the X-ray generator.

The depth at which the X-ray beam penetrates into the crystal causes angular broadening, which degrades the resolution. This parameter depends on the material of the crystal and can be expressed as in Equation 6 below.

Δθ ₃ = ln2cosθ / 4μR

Where μ represents the linear absorption coefficient of the crystal at the energy determined by the Bragg angle.

By the above X-ray optical system, the following measurement operation is performed on the sample.

1) Measurement of X-ray absorption and electron emission amount

The measurement of the amount of absorption of X-rays absorbed in the sample (test piece) proceeds as follows in the transmission-absorption method. The intensity (Io) of the monochromatic light incident on the sample is measured with a monitoring X-ray detector, and the gas proportional X-ray detector is placed behind the sample to measure the intensity (I) of the passed X-rays. Such measurements are made continuously at small energy intervals (e.g., 1 eV) to obtain X-ray absorption spectra. If this is expressed as an expression, it is as follows.

μ (E) x = ln (Io / I)

Where μ (E) is the linear absorption coefficient of the sample material and x represents the thickness of the sample.

When X-rays are irradiated onto the surface of the sample, the intensity of incident monochromatic light is measured by a monitoring X-ray detector, and the amount of electrons emitted from the sample surface is measured by an electron detector (channeltron). FIG. 14 is an X-ray absorption spectrum of a copper (Cu) thin film (thickness 13 microns) obtained by continuously changing energy, and FIG. 15 is a graph illustrating the conversion of the copper (Cu) absorption spectrum of FIG. Each spectrum is shown. FIG. 16 is an electron emission spectrum obtained by an electron dosimetry method near a Ti absorption edge for a TiN thin film sample (thin film structure: TiN (thickness 110 nm) / Si wafer). Here, in particular, the spectrum of FIG. 15 is scientifically referred to as an extended X-ray absorption fine structure (EXAFS) spectrum, and the spectrum of FIG. 16 is referred to as an X-ray absorption near edge structure (XANES) spectrum.

2) Measurement of fluorescence X-ray emission amount

When the X-rays are irradiated to the material, reactions between the atoms of the material and the incident photons occur to emit fluorescence X-rays from the atoms of the material. The amount of emitted fluorescent X-rays is proportional to the amount of absorbed incident X-rays. FIG. 17 shows the fluorescence X-ray emission spectrum of the same TiN thin film sample as used in FIG. 16.

3) Measurement of electron emission amount according to sample angle

When X-rays are irradiated to the material, reactions between the atoms of the material and incident photons occur to release electrons from the atoms of the material. However, since electrons have a very high absorption coefficient compared to X-rays, electrons that are actually released to the surface of the detector and captured by the detector are emitted in the range of several hundred nm (nanometer) from the surface of the material. Therefore, the amount of electrons emitted varies depending on the angle between the incident X-rays and the sample surface. Accurately measuring this can determine the process (mechanism) of electrons induced by X-rays and the escape depth of the electrons. 18 is an electron emission spectrum measured while varying the angle between the Ge (111) crystal plane and the incident X-ray at energy (11.110 keV) of the germanium (Ge) X-ray absorption edge. At this time, the direction of the incident X-ray was fixed, the angle of the electron detector was fixed at 60 ° with respect to the X-ray, and only the angle of the sample was changed.

4) Monochromated energy range and energy resolution of the measurement spectrum

In FIG. 11, an absorption edge (40.45 keV) of cerium (Ce) was confirmed, and in FIG. 13, a characteristic X-ray Lα1 peak (0.929 keV) of copper (Cu) was confirmed. Thus, the device can obtain monochrome X-rays in the range of at least 0.93 keV to 40.45 keV. By the way, as shown in the spectrum, this energy range can be further extended, and in real devices, to achieve monochromatic light in the range 0.479keV to 41.6keV.

19 is a spectrum showing the spectral energy resolution of the device of the present invention. Optical energy scanning is performed in 0.2 eV steps in the range of 8.02 keV to 8.055 keV in the vicinity of the Cu-K _α doublet. The full width at half maximum is determined by the following method. The energy difference between Cu-K _α1 (8.04778keV) and Cu-K _α2 (8.02783keV) is 19.95 eV, which corresponds to a distance of 112.5 ± 0.5 mm. Therefore, 1 mm = 0.1773 ± 0.0008 eV. The half width in the spectrum is 15.5 ± 0.5mm, corresponding to 2.75eV. As is known, since the original line width of Cu-K _α is 2eV, the absolute energy resolution (ΔPhE) is 1.89 ± 0.06eV in the 8keV region, and the relative energy resolution (ΔPhE / PhE) is (2.35 ± 0.07) × 10 ^{− 4}

5) Measurement of rocking curve

Since the apparatus of the present invention enables double diffraction by the crystal of the monochromator and the crystal of the sample, the double crystal diffraction can be analyzed. Therefore, the rocking curve of the single crystal obtained in the professional dual diffraction X-ray analyzer can be obtained in both the diffraction X-ray detection mode and the electron emission mode. 20 shows InP single crystals with X-ray energy fixed to Cu-K _α1 line (8.04778keV), Bragg diffraction angle fixed at 31.57 °, locked samples, and repeated repeated measurements with a reflective X-ray detection method. This is the rocking curve for the (004) plane. At this time, the locking step is 1 ± 0.2 arcsec and the position reproducibility is ± 4 arcsec.

As described above, in the X-ray electron spectroscopy apparatus according to the present invention, since a plurality of units having different functions are provided in one apparatus system, the following effects can be obtained.

1) A short wavelength can be obtained in a wide band of soft and hard X-rays. The reason for making this possible is that (i) the X-ray generator and the vacuum chamber are connected in one vacuum space. That is, since a window using a beryllium thin film is not employed between the two units, soft X-rays of 2 keV energy or less can be used. (ii) Six different monochromator crystals were employed. (iii) The Roland sector radius of 600 mm was implemented. (iv) The manufacturing precision of each moving part was secured, and the control precision of driving the mechanical movement was secured. (v) A large vacuum chamber was constructed and designed to prevent deformation in vacuum and air so that Roland sectors and precision components with a 600 mm radius can be mounted and driven precisely in both vacuum and air.

2) Hard X-ray EXAFS and XANES experiments can be performed on soft X-ray EXAFS and XANES on one system. This is because broadband X-ray monochromatic light can be obtained.

3) The elements from oxygen to uranium (U) can be analyzed qualitatively and quantitatively. This is because a vacuum of 1 × 10 ⁻⁴ Torr or more is required for the electron detection experiment using a channeltron electron detector, because the vacuum state of 1 × 10 ⁻⁶ Torr is maintained in the apparatus of the present invention.

4) Transmission X-ray absorption, electron emission, and fluorescence emission can be measured, and they can be measured simultaneously under the same conditions. This is because the placement of samples and detectors, detector mechanisms and operating programs are designed to meet these requirements.

5) A rocking curve can be obtained and a standing wave technique experiment can be performed. This is because it undergoes a double crystal diffraction process.

6) Experiment with total reflection. This is because there is little beam divergence, and the angle of the incident monochromatic light path and the surface of the sample can be precisely controlled from the angle at which total reflection occurs (0.1 ° or less) to 0.001 °.

7) The apparatus of the present invention can be used not only in a vacuum but also in the air according to the experimental method, so that the optical axis adjustment is relatively easy and provides many experiment opportunities.

Claims (20)

An X-ray generator for generating X-rays; An X-ray incoming converging device for converging X-rays generated from the X-ray generator; A monochromator for converting the X-rays passing through the X-ray incoming converging unit into a monochromatic X-ray having a short wavelength; An X-ray transmitting converging unit for converging and transmitting the monochromatic X-rays transmitted from the monochromator; An X-ray monitoring apparatus for monitoring a monochromatic X-ray having passed through the X-ray transmitting convergence unit; An X-ray photon detector for detecting photons of X-rays incident on any specimen via the X-ray monitoring apparatus; An electron detector for detecting electrons emitted from the specimen by X-rays incident on any specimen via the X-ray monitoring device; An X-ray detector for detecting X-rays reflected and emitted from the specimens and X-rays passing through the specimens by X-rays incident on any specimen through the X-ray monitoring apparatus; And And a control unit for controlling and signal processing of each of the components. The method of claim 1, X-ray electron spectroscopy, characterized in that the remaining components except the X-ray generator and the control unit is installed in the vacuum chamber. The method of claim 1, The X-ray generator is X-ray electron spectrometer, characterized in that for generating a white X-ray. The method of claim 1, Wherein the X-ray incoming and outgoing convergence apparatus is characterized in that the collimator X-ray electron spectroscopy. The method of claim 1, And the X-ray photon detector is a gas proportional detector. The method of claim 1, The X-ray electron detector is an X-ray electron spectrometer, characterized in that the channeltron. The method of claim 1, X-ray detector is an X-ray electron spectrometer, characterized in that the scintillation detector. The method of claim 1, The control unit includes a vacuum gauge control unit and a relay board, a detection device controller for controlling each detection device, a stepping motor controller for controlling a plurality of stepping motors enabling mechanical movement of each detection device, and An X-ray electron spectroscopic analyzer comprising a DC power supply for supplying DC power, and a first and second turbo molecular pump controller. The method according to claim 1 or 8, The control unit is connected to a computer that stores a specific operating program for operating the devices and the control unit, characterized in that the X-ray electron spectrometer. The method of claim 2, And a circular Roland sector for arranging the Roland circle of the light energy scanning mechanism, the monochromator, and the specimen detection unit, in the vacuum chamber. The method of claim 2, X-ray electron spectroscopy, characterized in that the linear chamber is provided inside the vacuum chamber for supporting the circular Roland sector. The method of claim 11, The two linear guides are fixed to both ends of the circular Roland sector, respectively, X-ray electron spectroscopy, characterized in that the Roland sector is fixed so as to move freely along each linear guide. The method of claim 10, And a sapphire plate is attached to a lower portion of the support of the Roland sector so that the circular Roland sector and the specimen detector body may slide. The method of claim 2, And the bottom surface of the vacuum chamber is processed such that the flatness is within 1 micron with respect to the bottom surface area. The method of claim 1, The monochromator X-ray electron spectroscopy apparatus characterized in that it has a six-sided drum revolver that can be used by mounting six crystals with different crystal plane spacing at the same time. The method of claim 1, And the X-ray generator and the vacuum chamber are connected to a vacuum bellows tube and a gate valve to form a vacuum space. The method of claim 10, The circular Roland sector X-ray electron spectrometer, characterized in that the radius of 600mm. The method of claim 1, X-ray electron spectroscopy apparatus characterized in that it further comprises a voice message system to determine whether the normal operation of the device by generating a specific sound in accordance with the operation of the device. The method of claim 2, The inside of the vacuum chamber is X-ray electron spectroscopy apparatus, characterized in that maintained at a pressure of 1 × 10 ^-6 Torr. The method of claim 10, And the Roland circle arrangement is an arrangement structure in which the center line of the incident beam incident on the sample from the light source and the center line of the reflected beam are symmetrical with respect to the normal of the crystal plane of the sample.

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