JP2656681B2 - Surface analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface analyzer using X-ray spectroscopy.

[0002]

2. Description of the Related Art The field of solid surface chemistry is not only important as a basic research field, but also deeply related to various industrial practical problems such as adsorption / desorption, catalysis, corrosion, electrode reaction, friction, and electronic properties. It is a very important area because it is related. For example, when it comes to catalysis, most processes in the chemical industry are not only driven by catalysts, but in recent years catalysts have played an important role, especially in solving resource, energy and environmental issues. ing. Thus, in the past, there has been a vast accumulation of empirical facts in this area. However, until now there has been no effective means for directly examining the surface of a substance, and an era of long-term guesswork about its nature based on indirect information has continued for a long time.

However, in recent years, the development of various physical and chemical devices has been rapidly progressing, and the arrangement of atoms on a solid surface, chemical composition, electronic state, vibration state, depth distribution from the surface, etc. There is an increasing tendency to create substances, materials, devices, and the like that have excellent functions by controlling data. Along with this trend, the importance of the means and method for measuring the solid surface state has become extremely large. Against this background, a scanning electron microscope is now widely used as the most common type of surface analyzer. In this scanning electron microscope, an electron beam emitted from an electron gun is converged extremely finely by a condenser lens, and is irradiated on a sample surface while being scanned by a deflection coil, and reflected electron emitted from the irradiated sample surface portion. Alternatively, secondary electrons are captured by an electron beam detector and amplified, and the amount of electron beams can be modulated and displayed on a CRT for observation. When the scanning of the electron beam on the sample surface and the scanning on the CRT are synchronized, an enlarged image of the sample surface can be obtained on the screen of the CRT as a reflection or secondary electron beam image.

When observing the surface of a sample with the above-mentioned scanning electron microscope, not only the crystal orientation difference and the different phase, but also the unevenness and the stepped structure cause a difference in the amount of the emitted electron beam.
They are all detected as image contrast. Therefore, the surface of the sample can be observed in a non-destructive state without corroding the sample with respect to the grain size and shape of the crystal grain, the shape and distribution of the precipitate, and the like.

[0005]

In the scanning electron microscope having the above-described structure, the surface resolution can be reduced to 100 angstrom or less by narrowing the electron beam. , Will be a fairly large area. This reason is believed to be due to the reason described below.

FIG. 18 shows a sample obtained by forming a thin film H on the surface of a base material B and observing the sample by applying a high energy (for example, 20 keV) electron beam to the sample using the scanning electron microscope. This shows the state of the electron beam sunk into the sample. As shown in FIG. 18, this type of electron beam penetrates the thin film H of the sample and penetrates deeply into the substrate B in the form of a droplet, and both the fluorescent X-rays from the thin film H and the fluorescent X-rays from the substrate B There is a problem that causes. Therefore, when the composition analysis is performed by the fluorescent X-rays excited by the electron beam of the scanning electron microscope having the above structure, there is a problem that the thin film H thinner than the drop-in portion cannot be accurately analyzed. Especially,
Since the drop-in portion reaches a depth of several μm, a thin film region having a thickness of 0.1 μm (1000 Å) or less cannot be accurately analyzed. Furthermore,
When the liquid drop-in portion is formed, the fluorescent X-ray dose from the thin film H and the liquid X-ray dose from the liquid immersion portion are observed in a mixed manner, so that the signal-to-noise ratio (S /
N ratio, electron dose from thin film and fluorescence X from liquid-like part
The ratio to the dose).

The present invention has been made in view of the above circumstances, and it is possible to capture a secondary electron beam from a sample surface and obtain an enlarged image of the secondary electron beam, and at the same time, capture characteristic X-rays and analyze components of the sample surface. 1.7 keV or less
C, N, O, F, and N that can be analyzed only from characteristic X-rays
e, Na, Mg, and Al can be accurately analyzed
It is another object of the present invention to provide a surface analysis apparatus and a surface analysis method capable of obtaining a diffraction pattern by a reflected electron beam.

[0008]

According to a first aspect of the present invention, there is provided a vacuum container for storing a sample.
Is connected to this vacuum vessel and the electron beam is incident on the sample
Generated from the sample connected to the electron gun and the vacuum vessel
An electron beam detector for detecting the irradiated secondary electron beam;
The fluorescent X-rays from the sample surface area near the total reflection angle of X-rays
Energy dispersive X-ray detector for detecting
The vacuum container is evacuated separately from the inside of the vacuum container.
A flexible connection chamber is formed, and the energy
Lugie-dispersive X-ray detector is detachably attached to the vacuum vessel
It is characterized by the fact that

According to a second aspect of the present invention, there is provided a surface analysis apparatus according to the first aspect, wherein the excitation is performed.
Fluorescent electron beam diffracted and reflected on the sample surface
It is characterized by comprising a fluorescent plate for displaying.

According to a third aspect of the present invention, there is provided a surface analyzer according to the first or second aspect of the present invention.
The incident angle of the electron beam on the sample to 15 ° or less
It is characterized by becoming.

According to a fourth aspect of the present invention, there is provided a surface analyzer according to the first or second aspect of the present invention.
The incident angle of the electron beam on the sample to 4 ° or less
And set the extraction angle of fluorescent X-rays from the sample to 4 ° or less.
It is characterized by becoming.

According to a fifth aspect of the present invention, there is provided a surface analysis apparatus according to any one of the first to fourth aspects, in order to solve the above-mentioned problems.
, Electron beam detector and energy dispersive X-ray detector
Is provided on the side of the sample in the direction of incidence of the electron beam.
Features.

[0013]

[0014]

When the surface of the sample is irradiated with an electron beam, the surface of the sample is excited to emit X-rays and secondary electron beams. Therefore, by detecting the X-rays with an energy dispersive X-ray detector and detecting a secondary electron beam with an electron beam detector, the component analysis of the sample by X-ray analysis and the sample surface by secondary electron beam analysis can be performed. An enlarged image can be obtained at the same time. Further, the amount of X-rays emitted from the sample is large in the total reflection angle region of X-rays of 4 ° or less, so that by detecting X-rays at this angle, a large amount of X-rays can be detected, thereby providing precise X-rays. Be able to analyze. Further, by injecting the electron beam into the sample at an angle of 4 ° or less, X-rays and secondary electron beams excited only from the surface portion can be measured without causing the electron beam to sneak into the sample, This allows an accurate analysis of the surface portion. In addition, by attaching the energy dispersive X-ray detector to the vacuum container via a spare room in a detachable manner, the energy dispersive X-ray detector can be removed without breaking the vacuum state of the vacuum container, and the The distributed X-ray detector can be shared and used by a plurality of vacuum vessels.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a schematic configuration of a main part of one embodiment of the present invention. In FIGS. 1 and 2, 1 is a substrate-like sample, 2 is an electron gun, and 3 is an energy dispersive X-ray detection. Reference numeral 4 denotes an electron beam detector. The sample 1 has a thin film or a thick film to be analyzed formed on the surface thereof, and the electron gun 2 has an electron beam (energy particle) incident on the surface of the sample 1 at a predetermined incident angle θg. The energy dispersive X-ray detector 3 detects fluorescent X-rays (characteristic X-rays) generated from the surface of the sample 1, and the electron beam detector 4 detects secondary electrons generated from the surface of the sample 1. This is to detect a line.

Between the energy dispersive X-ray detector 3 and the sample 1, a window 5 made of Be or an organic thin film having little X-ray absorption and a slit plate 6 are provided as shown in FIG. The dispersive X-ray detector 3 includes a window 7 made of Be or an organic thin film having little X-ray absorption, a semiconductor X-ray detector 8, and an FET 9 connected to the semiconductor X-ray detector 8, and the FET 9 is an amplifier. It is connected to a wave height analyzer 10 provided.

An energy dispersive X-ray detector (energy dis
persive X-ray detector (EDX) is a characteristic X-ray (or fluorescent X-ray) excited by predetermined energy particles
Utilizing the fact that when electrons are incident on the detector, a pair of electrons and holes is generated in proportion to the energy of the X-rays.
The intensity of the line can be converted into an electric signal and detected.

The semiconductor X-ray detecting section 8 will be described. The semiconductor X-ray detecting section 8 is composed of p-doped Si doped with B or the like.
Thermal diffusion of Li into the single-crystal semiconductor, Si (Li)
This is generally called a semiconductor X-ray detecting element.
When a voltage is applied to the semiconductor X-ray detector 8 and X-rays are incident on the voltage, electrons proportional to the energy of the X-rays,
Hole pairs are formed in the semiconductor X-ray detector 8 and these are collected by both the positive and negative electrodes formed in the semiconductor X-ray detector 8 and output as current pulses. The intensity of the input X-ray energy can be detected based on the intensity of the electric signal generated by the X-ray detector 8. The windows 5 and 7 made of Be or an organic thin film are used because of their high X-ray transmission efficiency.

On the other hand, the electron gun 2 comprises a filament 11, a Wehnelt cylinder 12, an anode 13, and a first condenser lens 1.
4, a second condenser lens 15, and a deflection coil 16, and a scanning electrode 17 is provided on the deflection coil 16 of the electron gun 2.
The scanning electrode 17 is connected to a cathode ray tube 18 for observation, and the cathode ray tube 18 is connected to the electron beam detector 4. According to the electron gun 2 having the above configuration, the desired position on the sample surface can be irradiated with the electron beam by the action of the deflection coil 16, and the secondary electron beam generated by exciting the sample is detected by the electron beam detector 4. Can be modulated to the brightness on the screen of the cathode ray tube 18.

In order to analyze the sample surface using the apparatus shown in FIGS. 1 and 2, an electron beam is incident on the sample surface by the electron gun 2 at an incident angle θg (0 to 15 °, most preferably 4 ° or less). I do. Then, the sample surface is excited to emit fluorescent X-rays (or characteristic X-rays) and secondary electron beams, but at a predetermined X-ray extraction angle θt (0 to several ゜, preferably 4 ° or less) from the sample surface. When characteristic X-rays are detected by the energy dispersive X-ray detector 3, the X-ray detection sensitivity is remarkably improved at the X-ray total reflection angle (0 to several degrees, usually 4 degrees or less). The highly sensitive detection also provides information on the elemental analysis of the sample surface state and the atomic arrangement structure on the surface. Further, since a secondary electron beam is also generated from the sample surface excited by the electron beam, an enlarged image of the sample can be observed by the electron beam detector 4 as in the conventional case.
Here, it is known that the X-ray total reflection angle θc is given by the following equation. θc = 1.14 × ρ ^0.5 × E where θc
Is deg (degrees), ρ is the density of the reflecting substance (g / cm ³ ), and E is the X-ray energy (keV). For example, YLα ray (energy 1.92 keV)
However, the angle of total reflection at Au (density of 19.3 g / cm ³ ) is θc (YLα-Au) = 2.60 °. Similarly, Au
The angle at which the M line (2.15 keV) is totally reflected by Si (2.33 g / cm ³ ) is θc (AuM-Si) = 0.81 °. As described above, the total reflection angle of X-rays varies depending on the combination of the type of X-rays to be measured and the substance to be reflected, but is basically 4 ° or less.

FIGS. 1 and 2 show only the arrangement of the main parts of the apparatus of the present invention. FIGS. 3 and 4 show the schematic configuration of the apparatus of the present invention, and FIGS. The detailed structure is shown. 3 and 4, reference numeral 20 denotes a vacuum container containing the sample 1, and the vacuum container 20 is connected to a vacuum exhaust device (not shown) so that the inside can be evacuated.
A sample holder 22 for holding the plate-shaped sample 1 is provided at the center of the upper inside of the vacuum vessel 20, and the plate-shaped sample 1 can be horizontally supported on the bottom of the sample holder 22. .

A cylindrical support port 25 is protruded from a side wall 23 of the vacuum vessel 20, and an energy dispersing type X is provided at a tip end of the support port 25 via flange plates 26 and 27.
A line detector 28 is attached. The energy dispersive X-ray detector 28 includes a tank 29 for storing liquid nitrogen.
An L-shaped probe 30 protruding from the bottom of the tank 29;
1 and a flange plate 27 fixed to the auxiliary pipe 31.
A preliminary chamber 32 is formed inside the auxiliary pipe 31 by being bolted to the flange 26 on the side, and the preliminary chamber 32 communicates with the support port 25 via flange plates 27 and 26. Further, a vacuum exhaust device 33 is connected to the auxiliary pipe 31 so that the auxiliary chamber 32 can be independently evacuated. The probe 30 is provided with a window 34 made of Be or an organic thin film at the tip thereof, and the semiconductor X-ray detector 8 for X-ray measurement, the FET 9 and the like are accommodated inside the window 34.

A cylindrical bellows member 35 made of metal such as stainless steel is provided inside the support port 25.
The bellows member 35 is provided at the tip of the bellows member 35 so as to penetrate the side wall 23 of the vacuum container 20.
Is provided. On the other hand, on the inner bottom of the vacuum vessel 20,
An evaporation source 38 for forming a film is provided on the bottom surface side of the sample 1. The vapor deposition source 38 contains the raw material 4 inside the crucible 39.
The crucible 39 is provided with a deflecting electron beam irradiating device 41 below the crucible 39. The irradiating direction of the electron beam is deflected to bend, the material 40 is irradiated, and the material 40 is evaporated to form a film on the sample 1. You can do it. The evaporation source 38 is used when it is necessary to perform a film forming process on the sample 1 mounted on the sample holder 22.

On the other hand, as shown in FIG. 4, below the sample holder 22, there is provided a gas supply device 43 comprising an annular tube.
The gas supply device 43 is connected to a gas supply source 4 such as an oxygen cylinder through a connection pipe 44 penetrating the side wall 23 of the vacuum vessel 20.
5 is connected. The gas supply device 43 has a plurality of through-holes formed in the upper surface of an annular tube along the circumferential direction thereof. The gas supplied from the gas supply source 45 is supplied to the sample holder 2.
2 can be supplied to the space on the bottom side.

Further, as shown in FIG. 4, a mounting port 47 is formed on one side of the vacuum vessel 20.
An electron gun 2 shown in FIGS. 1 and 2 is attached to 7, and the electron gun 2 can irradiate an electron beam (energy particles) to the sample 1 at the bottom of the sample holder 22.

The apparatus of the present invention will be described below in more detail with reference to FIGS. 5 to 10, FIG.
4 are denoted by the same reference numerals and the description thereof will be omitted. As shown in FIG. 7, a number of auxiliary ports 50, 5 and
1, 52, 53, 54, and 55 are protruded in various directions so that various devices can be attached.

The structure of the support structure of the probe 30 described above with reference to FIG. 3 has the structure shown in FIG. 8 in detail. That is, flange plates 26 and 27 are attached to the support port 25 of the vacuum vessel 20 via the adjustment flange 60, and a slide stand 61 is attached to the outside of the flange plate 27, and the slide stand 61 has a curved outer surface. Guide rails 62, 62 are formed, and these guide rails 62
The slide base 63 which moves along these is mounted on the outside of the base.

On both sides of the outer periphery of the slide base 61, U-shaped slide pieces 65 as shown in FIG. 8 are formed, and the slide base 61 is sandwiched between the slide pieces 65, 65 with the flange plate 27 interposed therebetween. 27 are movably engaged. Further, adjustment bolts 66 are penetrated through the respective slide pieces 65, and the respective adjustment bolts 66 are rotatably provided with their ends in contact with the outer peripheral portion of the flange plate 27. A guide surface 67 having a concave curved surface shape matching the guide rail 62 is formed on the surface of the slide base 63 on the guide rail 62 side, and the slide base 63 can move along the guide rails 62, 62. It has become. An adjustment bolt 70 penetrates a projection 68 projecting from the slide base 61.
Is rotatably provided with its tip abutting on the side of the slide base 63.

Further, the slide base 61 and the slide base 63 pass through the inside of the support port 25 through them, pass through the tip of the bellows member 35, and pass through the vacuum container 20.
A protective tube 71 is attached to the center of the protective tube 71. A window 5 made of Be is attached to the distal end of the protective tube 71, and a slit plate 6 is attached inside the window 5. The protection tube 71 has a double structure, and has a passage 73 formed therein for circulating cooling water.

The protective tube 71 is formed to have a size capable of accommodating the probe 30 of the energy dispersive X-ray detector 3, and is provided at the base end side of the protective tube 71, that is, on the outer surface of the slide base 63. A support base 77 for fixing the distributed X-ray detector 3 is provided. Although not shown in FIG. 8, a pipe connection portion for connecting to the vacuum exhaust device 33 is formed on the base end side of the protection tube 71, and the energy dispersive X-ray detector including the probe 30 is provided. When the probe 3 is attached to the flange plate 27 and the probe 30 is inserted into the inside of the protection tube 71, the space between the inner surface of the protection tube 71 and the outer surface of the probe 30 and the spare chamber 32 described above are separated by the vacuum exhaust device 33. It can be evacuated. That is, as shown in FIG.
A connection chamber 79 is formed by the preparatory chamber 78 and the preparatory chamber 32 surrounded by the outer surface of the “0”.

The support base 77 is supported by a movable base 81 via a spring 80, as shown in FIG. 10, and the movable base 81 is supported by a base 83 via an X-type telescopic mechanism 82. The extension mechanism 82 is provided with an adjustment bolt 84.
The upper and lower positions can be adjusted.

Next, a case where a surface analysis is performed using the apparatus having the above configuration will be described. In order to analyze the sample 1 having the thin film H formed on the surface, the inside of the vacuum container 20 is evacuated after storing the sample 1 in the vacuum container 20. Further, the probe 30 of the energy dispersive X-ray detector 3 is connected to the protective tube 7.
1 to support the whole of the energy dispersive X-ray detector 3 on the support base 77. Further, the vacuum chamber 33 evacuates the preliminary chamber 32 around the probe 30 and the inside of the protective tube 71. In this state, the surface of the sample is irradiated with an electron beam from the electron gun 2 at a predetermined incident angle. This angle of incidence is
4 ° or less is preferred. Although this incident angle is related to the thickness of the thin film H on the sample surface, the smaller the incident angle is, the smaller the amount of the electron beam penetrating into the thin film H, so that it can be applied to a thinner thin film H.

That is, the surface of the sample on which the electron beam is incident is excited, and the secondary electron beam and the fluorescent X-ray are emitted. FIG. 11 shows an excited state when an electron beam is incident on the sample 1 at a low incident angle as described above. In this state, the sample 1 does not sneak into a droplet, and only the thin film H is excited to emit characteristic X-rays and secondary electron beams unique to the components of the thin film H.

Here, the scanning coil 17 is used to control the deflection coil 16.
Is adjusted to deflect the electron beam, the secondary electron beam is sequentially detected by the electron beam detector 4, and an enlarged image of the sample surface portion can be displayed on the CRT 18. Here, the image obtained on the CRT 18 is equivalent to that obtained from a conventional scanning electron microscope.

As shown in FIG. 11, the excited thin film H emits fluorescent X-rays (characteristic X-rays). However, by irradiating the sample 1 with an electron beam at a shallow angle of 4 ° or less, the liquid crystal does not penetrate into the substrate B in the conventional manner, and the characteristic X-ray generated does not occur. It increases sharply at a predetermined extraction angle (total reflection angle of characteristic X-rays) of 4 ° or less. By extracting characteristic X-rays with the energy dispersive X-ray detector 3 at this angle, characteristic X-rays corresponding to the components of the thin film H can be specified,
Accurate surface analysis can be performed.

The energy dispersive X-ray detector 3
The inclination angle of the probe 30 with respect to the sample 1 (that is, the extraction angle of the characteristic X-ray) can be adjusted as described below. When the adjustment bolt 70 shown in FIG. 8 is rotated,
Since the tip of the adjusting bolt 70 presses the side surface of the slide base 63, the slide base 63 is guided by the guide rails 62, 6.
Move along 2. Here, the probe 30 of the energy dispersive X-ray detector 3 is mounted on the slide base 63 and the support base 7.
7, the energy dispersive X-ray detector 3 is tilted together with the slide base 63. Thus, the inclination angle of the probe 30 can be changed, and the extraction angle of the characteristic X-ray from the sample 1 can be adjusted. Here, the take-out angle is preferably set to 4 ° or less.

The height position of the energy dispersive X-ray detector 3 can be adjusted by rotating the adjusting bolt 84 shown in FIG.

As described above, the inclination angle, the vertical position, and the horizontal position of the probe 30 of the energy dispersive X-ray detector 3 can be adjusted.
Energy-dispersive X using a complex structure as shown in
The energy dispersive X-ray detector 3 supports the X-ray detector 3 in a tank 29 in which liquid nitrogen for cooling is sealed.
In addition, since the weight is large, the structure of the probe 30 is complicated, and the cost of the apparatus is high, it is necessary to precisely adjust the inclination angle of the probe 30 for the purpose of preventing damage to the energy dispersive X-ray detector 3 and the like. Because there is.

Before the analysis of the sample 1, the evacuation device 33 shown in FIG. 3 is operated to evacuate the space around the preliminary chamber 32 and the probe 30 so that the characteristic X Since the line can be incident on the semiconductor X-ray detector 8 of the probe 30 via the vacuum portion and the windows 34 and 36 made of Be or an organic thin film, the characteristic X-ray can be suppressed from being absorbed in the middle as much as possible. . On the other hand, the probe 30
When an air layer exists between the tip of
Since characteristic X-rays having energy of eV or less are absorbed or attenuated, C, N, and O can be analyzed only from characteristic X-rays of 1.7 keV or less by evacuating as described above. , F, Ne, Na, Mg, and Al can be accurately analyzed. In addition, about the element whose atomic number is larger than the above-mentioned element, in addition to the Kα ray, the Kβ ray,
Since Lα rays, Lβ rays, Lγ rays, M rays, etc. are generated, it can be utilized for analysis by using an appropriate characteristic X-ray according to each element.

FIG. 12 shows another embodiment of the apparatus of the present invention. The device of this embodiment has a configuration in which a fluorescent screen 90 is added to the device of the above embodiment. Part of the electron beam emitted from the electron gun 2 to the sample 1 is diffracted and reflected on the sample surface. If the fluorescent screen 90 is installed in the direction of emission of the reflected electron beam, a pattern unique to the reflected high-speed electron beam can be recorded. Since this pattern is a diffraction pattern unique to the crystal structure of the sample surface, analyzing this pattern can be used effectively for the analysis of the sample 1.

Therefore, by providing the fluorescent screen 90, it is possible to obtain an enlarged image by the electron beam detector 4, and to perform component analysis by the energy dispersive X-ray detector 3, and at the same time,
The diffraction pattern of the reflected high-speed electron beam can be obtained by the fluorescent plate 90, and there is an effect that the sample 1 can be analyzed comprehensively from three surfaces. The fluorescent plate 90 can be easily attached to the vacuum vessel 20 by attaching it to the spare port 52 shown in FIGS.

(Test Example 1) Using the apparatus of the first embodiment described above, YBa ₂ was formed on the (100) plane of an MgO substrate.
Surface analysis was performed on a sample on which an oxide superconducting thin film having a composition of Cu ₃ O _{x and} a thickness of 800 Å was formed. This oxide superconducting thin film has composition analysis data by IPC (inductively coupled plasma) emission spectroscopy, Y: Ba: Cu = 1: 1.
It has been found that the composition is 1.9: 2.8. After the internal pressure of the vacuum vessel was set to 1 × 10 ⁻⁷ Torr, an electron beam having an energy of 20 keV was incident on the surface of the sample at incident angles (θg) of 4 °, 11 °, and 90 °, and the energy was increased. The extraction angle (θg) of the dispersion type X-ray detector is 4
The analysis was performed by setting the following, {5, 8}, and 10-13, respectively.

The above results are shown in FIGS. FIG.
In the case of θg = 4 ° shown in FIG. 3, no Mgkα ray of the substrate MgO was observed at all, and only the characteristic X-rays from the YBa ₂ Cu ₃ O _x thin film were obtained. Only characteristic X-rays of the element could be captured very clearly. In the field of analysis of such an oxide superconducting thin film, there has been no conventional example in which characteristic X-rays of only the oxide superconducting thin film are clearly captured. In FIG. 13,
Although AlKα rays were detected, this was considered to be characteristic X-rays from Al in the Al sample holder, and CKα
The line seems to be a characteristic X-ray from the carbon tape used to fix the sample to the sample holder. In the state shown in FIG. 13, the composition analysis of the thin film can be performed. Therefore, the incident angle of the X-ray used in the present invention may be in the range of 11 ° or less. Note that the incident angle at which the amount of X-rays sunk into the substrate can be suppressed to about several thousand angstroms (that is, about the thickness corresponding to the thickness of the film formed on the substrate surface) is limited to about 15 °. Therefore, the incident angle is preferably set to 15 ° or less. Further, by detecting a secondary electron beam separately from the result of the component analysis, it was possible to obtain an enlarged image equivalent to that of a conventional scanning electron microscope.

In the case of θg = 11 ° shown in FIG. 14, since some penetration of the electron beam is generated, the MgO
Although α rays are generated to some extent, the intensity of characteristic X-rays from the YBa ₂ Cu ₃ O _x thin film is also strong, so that there is no major problem in analyzing the composition of the thin film. Θg shown in FIG.
In the case of 90 °, the intensity of the MgKα ray of MgO on the substrate is strong, and the intensity of the characteristic X-ray from the YBa ₂ Cu ₃ O _x thin film is very weak. In this case, composition analysis of the thin film cannot be performed using characteristic X-rays.

(Test Example 2) A 50 Å thick thin film of Au was formed on the (100) plane of a Si substrate.
This was analyzed in the same manner as described above. Where incident angle θ
g is set to 4 °, the X-ray extraction angle θt is set to 0 to 3 °, and θt
Were set at 5 to 8 °, and θt was set at 10 to 13 °, respectively. FIG. 16 shows the result. As is clear from the results shown in FIG.
0 near the total reflection angle θc (AuM-Si) = 0.81 ° of the line
When it is set to 〜3 °, the M line of the characteristic X-ray of the Au thin film is the largest with respect to the Kα line of Si.

On the (100) plane of the Si substrate, a film thickness of 125
An Angstrom Au film was formed and analyzed in the same manner as above. However, the incident angle θg is set to 4 °, the X-ray extraction angle θt is 0 to 3 °, θt is 5 to 8 °,
The measurement was performed with θt set to 10 to 13 °. The result is shown in FIG. As is clear from the results shown in FIG. 17, the X-ray extraction angle θt is changed to the X-ray total reflection angle θc.
When (AuM-Si) is set to 0-3 ° near 0.81 °, the M-line of the characteristic X-ray of the Au thin film is larger than the Kα line of Si. What is clear from FIGS. 16 and 17 suggests that when the thickness of the thin film to be analyzed is about 100 Å, the characteristic X-ray of the thin film having the same intensity as the characteristic X-ray of the substrate can be detected. .

[0047]

As described above, according to the present invention, the surface of the sample can be excited by irradiating the surface with an electron beam from an electron gun to emit fluorescent X-rays and secondary electron beams. Therefore, X-rays are detected by an energy dispersive X-ray detector, and secondary electron beams are detected by an electron beam detector.
It is possible to simultaneously obtain an enlarged image of the sample surface by the component analysis of the sample by the line analysis and the analysis of the secondary electron beam. Therefore, there is an effect that it is possible to perform component analysis of the sample analysis portion while observing the enlarged image, which is impossible with a conventional analyzer.

Further, since the X-rays emitted from the sample increase at the total reflection angle of the X-rays of 4 ° or less, a large amount of the characteristic X-rays can be detected by detecting the characteristic X-rays at this angle. This allows precise analysis. Furthermore,
By injecting an electron beam into the sample at an angle of 4 ° or less, it is possible to measure X-rays and secondary electron beams excited only from the surface portion without causing the electron beam to sneak into the sample. Accurate analysis of thin parts of the surface can be performed.

According to the apparatus provided with the energy dispersive X-ray detector, the electron beam detector, and the fluorescent plate, the fluorescent plate can obtain a diffraction pattern of the reflected electron beam from the sample. Can be obtained, and the component analysis can be performed by the energy dispersive X-ray detector. Therefore, there is an effect that the sample can be comprehensively analyzed from the three analysis results.

Further, in the case where the energy dispersive X-ray detector is detachably attached to the vacuum vessel via the connection chamber, an air layer is interposed between the energy dispersive X-ray detector and the sample. Energy-dispersive X-ray detector can be used without any
There is an effect that even a line can be detected without causing attenuation or absorption. That is, it becomes possible to accurately analyze C, N, O, F, Ne, Na, Mg, and Al, which can be analyzed only from characteristic X-rays of 1.7 keV or less. In addition, by releasing the vacuum state only in the spare chamber, the energy dispersive X-ray detector can be removed without breaking the vacuum state of the vacuum vessel, and an expensive energy dispersive X-ray detector can be used in a plurality of vacuum vessels. It can be shared.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an arrangement of a main part of an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of an embodiment of the present invention.

FIG. 3 is a sectional view showing a part of one embodiment of the present invention.

FIG. 4 is a schematic view showing the entire configuration of the vacuum vessel of the embodiment shown in FIG.

FIG. 5 is a sectional view showing a detailed structure of one embodiment of the present invention.

FIG. 6 is a sectional view showing a detailed structure of one embodiment of the present invention.

FIG. 7 is a horizontal sectional view showing a detailed structure of one embodiment of the present invention.

FIG. 8 is a sectional view showing a support structure of the probe of the embodiment.

FIG. 9 is a rear view showing the support structure of the embodiment.

FIG. 10 is a side view showing the support structure of the embodiment.

FIG. 11 is a cross-sectional view showing an electron beam incident on a sample surface and an excited state of the sample surface when performing X-ray analysis using the apparatus according to the present invention.

FIG. 12 is a configuration diagram showing a second embodiment of the present invention.

FIG. 13 is a view showing a result of surface analysis of a first sample by the device of the present invention.

FIG. 14 is a view showing a result of sample surface analysis by a conventional apparatus.

FIG. 15 is a diagram showing a result of sample analysis by a conventional apparatus.

FIG. 16 is a diagram showing a result of surface analysis of a second sample by the apparatus of the present invention and a result of surface analysis of the same sample by a conventional apparatus.

FIG. 17 is a diagram showing the results of surface analysis of a third sample by the device of the present invention and the results of surface analysis of the same sample by the conventional device.

FIG. 18 is a cross-sectional view showing energetic particles incident on a sample surface by a conventional apparatus and an excited state of the sample surface.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Sample, 2 ... Electron gun, 3 ... Energy dispersive X-ray detector, 4 ... Electron beam detector, 7 ... Window part, 8 ... Semiconductor X-ray detector, 20 ... Vacuum container, 32 ... Preparatory chamber, 75 …
Preparatory room, 76: Connection room, θg: Electron beam incident angle, θ
t: X-ray extraction angle.

 ──────────────────────────────────────────────────続 き Continuing from the front page (73) Patent holder 000002255 Showa Electric Wire & Cable Co., Ltd. 2-1-1 Oda Sakae, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture (72) Inventor Toshio Usui 1-13-1 Shinonome, Koto-ku, Tokyo No. Inside the Superconductivity Engineering Research Center, International Superconducting Technology Research Center (72) Inventor Yuji Aoki 1-14-3 Shinonome, Shinonome, Koto-ku, Tokyo, Japan Inside the Superconducting Engineering Research Institute, Japan (72) Inventor Masayuki Kamei 1-14-3 Shinonome, Koto-ku, Tokyo International Research Center for Superconducting Technology, Superconductivity Engineering Laboratory (72) Inventor Tadataka Morishita 1-14-3, Shinonome, Shinonome, Koto-ku, Tokyo International Research Center for Superconducting Technology Within the Superconducting Engineering Laboratory (56) References JP-A-61-78041 (JP A) Patent Akira 60-100038 (JP, A)

Claims (5)

(57) [Claims] 1. A vacuum container for accommodating a sample, an electron gun connected to the vacuum container and incident an electron beam on the sample,
An electron beam detector connected to the vacuum vessel for detecting a secondary electron beam generated from the sample, and energy for detecting the excited fluorescent X-rays from the sample surface near the X-ray total reflection angle it comprises a a dispersion-type X-ray detector, said true
The vacuum container can be evacuated to an empty container separately from the inside of the vacuum container.
A connecting chamber is formed, and the energy dispersion is performed through the connecting chamber.
A surface analysis apparatus characterized in that a type X-ray detector is detachably attached to a vacuum vessel . 2. The surface analyzer according to claim 1, wherein
Electron beam diffracted and reflected at the excited sample surface
1. A surface analyzer comprising a fluorescent plate for fluorescent display of 3. The surface analyzer according to claim 1, wherein
, The incident angle of the electron beam on the sample is 15 ° or less
A surface analyzer characterized by being set to: 4. A surface analysis apparatus according to claim 1, wherein
The incident angle of the electron beam on the sample to 4 ° or less
And set the extraction angle of fluorescent X-rays from the sample to 4 ° or less.
A surface analyzer characterized by being defined . 5. The surface component according to claim 1,
Electron beam detector and energy dispersive X-ray
A surface analyzer, wherein a detector is provided on a side of an electron beam incident direction on a sample .