JPH0518730A - Surface analyzer - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention is capable of capturing a secondary electron beam from a sample surface excited by an electron beam to obtain an enlarged image thereof, and at the same time, capturing characteristic X-rays for component analysis of the sample surface. It is an object to provide an apparatus and method. According to the present invention, an electron gun for injecting an electron beam onto a sample surface, a detector for a secondary electron beam generated from the sample surface,
An energy dispersive X-ray detector that captures fluorescent X-rays from the sample surface at a total reflection angle. [Effect] By capturing the characteristic X-ray emitted from the excited sample surface at the total reflection angle, the component analysis of the thin film on the sample surface can be performed. Further, by capturing the secondary electron beam from the sample surface with the detector, a magnified image of the sample surface can be obtained, and the surface can be observed simultaneously with the component analysis.

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 field because it is related. For example, when it comes to catalysis, not only are most processes in the chemical industry driven by catalysts, but in recent years, catalysts have played an important role, especially in solving resource, energy and environmental problems. ing. Therefore, there has been a vast accumulation of empirical facts in the past in this field. However, until now, there has been no effective means for directly inspecting the surface of a substance, so that the era in which the nature of the substance has been speculated based on indirect information has continued for a long time.

However, in recent years, various physical and chemical devices have been rapidly developed, so that 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, etc. that have excellent functions by controlling the. Along with this tendency, the importance of the measuring means and the measuring method of the solid surface state has become extremely important. Against this background, the scanning electron microscope is now widely used as the most common surface analysis device. In this scanning electron microscope, an electron beam emitted from an electron gun is converged extremely finely by a condenser lens and irradiated on the sample surface while being scanned by a deflection coil and reflected electrons emitted from the irradiated sample surface portion. Alternatively, secondary electrons are captured and amplified by an electron beam detector, and the amount of electron beams can be modulated and displayed on a CRT for observation. Further, if the scanning of the electron beam flux on the sample surface and the scanning on the cathode ray tube are synchronized, an enlarged image of the sample surface can be obtained as a reflected or secondary electron beam image on the screen of the cathode ray tube.

When observing the surface of the sample with the scanning electron microscope, not only the crystal orientation difference and the different phase but also the unevenness and the step structure cause a difference in the amount of the emitted electron beam.
They are all detected as image contrast. Therefore, it is possible to observe the surface of the sample 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-mentioned structure, it is possible to reduce the surface resolution to 100 angstroms or less by narrowing the electron beam, but the actual fluorescent X-ray generation region is , Becomes a fairly wide area. The reason for this is considered to be as follows.

FIG. 18 shows a sample in which the thin film H is formed on the surface of the base material B, when observed by using the scanning electron microscope and injecting a high-energy (for example, 20 keV) electron beam into the sample. It shows the state of the electron beam penetrating into the sample. As shown in FIG. 18, this type of electron beam penetrates the thin film H of the sample and deeply penetrates into the base material B in the form of droplets, and both the fluorescent X-rays from the thin film H and the fluorescent X-rays from the base material B are obtained. There is a problem that causes. Therefore, when the composition analysis is performed by the fluorescent X-ray excited by the electron beam of the scanning electron microscope having the above-mentioned structure, there is a problem that the thin film H thinner than the drop-in portion cannot be accurately analyzed. In particular,
Since the depth of the droplet-like recess reaches several μm, it is impossible to accurately analyze a thin film region having a thickness of 0.1 μm (1000 Å) or less. Furthermore,
When the droplet-like underwater portion is generated, the fluorescent X-ray dose from the thin film H and the fluorescent X-ray dose from the liquid enemy-like underwater portion are observed as a mixture, so that the signal noise ratio (S /
N ratio, electron dose from thin film and fluorescence X from liquid enemies
There is a problem that the ratio with the dose) becomes worse.

The present invention has been made in view of the above circumstances, and a secondary electron beam from the sample surface can be captured to obtain an enlarged image thereof, and at the same time, characteristic X-rays can be captured to analyze the components of the sample surface. It is an object of the present invention to provide a surface analysis device and a surface analysis method capable of performing the above, and also capable of obtaining a diffraction pattern by a reflected electron beam.

[0008]

In order to solve the above-mentioned problems, the present invention comprises an electron gun for injecting an electron beam on the surface of a sample and a sample surface portion excited by the electron beam being incident. And an energy dispersive X-ray detector arranged to detect the fluorescent X-rays from the excited sample surface in the vicinity of the total reflection angle of the X-rays. It is equipped with.

In order to solve the above-mentioned problems, a second aspect of the present invention is to connect a vacuum container for containing a sample, an electron gun connected to the vacuum container for injecting an electron beam to the sample, and the vacuum container. Electron beam detector for detecting a secondary electron beam generated from the sample, and energy dispersive X-ray detection for detecting fluorescent X-rays from the surface of the excited sample near the total reflection angle of X-rays And a container.

In order to solve the above-mentioned problems, a third aspect of the present invention relates to a vacuum container for accommodating a sample, an electron gun connected to this vacuum container for injecting an electron beam to the sample, and connected to the vacuum container. Electron beam detector for detecting a secondary electron beam generated from the sample, an energy dispersive X-ray detector for detecting fluorescent X-rays from the excited sample surface, and the excited sample A fluorescent plate for fluorescently displaying the electron beam diffracted and reflected on the surface portion.

In order to solve the above-mentioned problems, the invention according to claim 4 is the surface analysis apparatus according to claim 2 or 3, wherein the vacuum chamber is provided with a connection chamber which can be evacuated separately from the inside of the vacuum container. And an energy dispersive X-ray detector is detachably attached via this connection chamber.

In order to solve the above problems, the invention according to claim 5 is the surface analyzer according to claim 1, 2, 3 or 4, wherein the incident angle of the electron beam with respect to the sample is set to 15 ° or less. It will be.

In order to solve the above-mentioned problems, the invention according to claim 6 is the surface analyzer according to claim 1, 2, 3 or 4, wherein the incident angle of the electron beam with respect to the sample is set to 4 ° or less. The extraction angle of fluorescent X-rays from the sample is set to 4 ° or less.

[0014]

By irradiating the surface of the sample with an electron beam, the surface of the sample is excited and X-rays and secondary electron beams are emitted. Therefore, the X-ray is detected by the energy dispersive X-ray detector and the secondary electron beam is detected by the electron beam detector, whereby the component analysis of the sample by the X-ray analysis and the sample surface analysis by the secondary electron beam analysis are performed. Enlarged images can be obtained at the same time. Also, since the X-rays emitted from the sample are mostly in the total reflection angle region of X-rays of 4 ° or less, a large amount of X-rays can be detected by detecting the X-rays at this angle. Be able to analyze. Further, by injecting the electron beam at an angle of 4 ° or less on the sample, it is possible to measure the X-ray and the secondary electron beam excited only from the surface portion without causing the electron beam diving phenomenon to the sample, This allows an accurate analysis of the surface area to be performed. In addition, by attaching the energy dispersive X-ray detector to the vacuum container via the auxiliary chamber in a detachable manner, the energy dispersive X-ray detector can be removed without breaking the vacuum state of the vacuum container, resulting in expensive energy consumption. The distributed X-ray detector can be commonly 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 sample, 2 is an electron gun, 3 is energy dispersive X-ray detection. Reference symbols 4 and 4 denote electron beam detectors, respectively. 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 particles) incident on the surface of the sample 1 at a predetermined incident angle θg. The energy dispersive X-ray detector 3 is for detecting fluorescent X-rays (characteristic X-rays) generated from the surface of the sample 1, and the electron beam detector 4 is a secondary electron generated from the surface of the sample 1. It detects lines.

Between the energy dispersive X-ray detector 3 and the sample 1, as shown in FIG. 2, a window 5 and a slit plate 6 made of Be or an organic thin film having a small X-ray absorption are provided, and the energy is reduced. The distributed X-ray detector 3 is provided with a window 7 such as Be or an organic thin film having a small X-ray absorption, a semiconductor X-ray detector 8, and a FET 9 connected to the semiconductor X-ray detector 8. The FET 9 is an amplifier. It is connected to the wave height analyzer 10 provided.

Energy dispersive X-ray detector (energy dis
Persive X-ray detector (EDX) is a characteristic X-ray (or fluorescent X-ray) excited by a given energy particle.
Is incident on the detector, an electron-hole pair that is proportional to the energy of the X-rays is generated to make the incident X-ray incident.
The intensity of the line can be converted into an electric signal and detected.

The semiconductor X-ray detector 8 will be described. The semiconductor X-ray detector 8 is composed of p-doped Si doped with B or the like.
Type semiconductor single crystal formed by thermal diffusion of Li, Si (Li)
It is generally called a semiconductor X-ray detecting element.
When a voltage is applied to the semiconductor X-ray detection unit 8 and X-rays enter the semiconductor X-ray detection unit 8, electrons proportional to the energy,
Hole pairs are formed in the semiconductor X-ray detection unit 8, and these are collected by both + and-electrodes formed in the semiconductor X-ray detection unit 8 and output as a current pulse. The intensity of the input X-ray energy can be detected by the intensity of the electric signal generated by the X-ray detector 8. The windows 5 and 7 made of Be or organic thin film are used because they have high X-ray transmission efficiency.

On the other hand, the electron gun 2 includes a filament 11, a Wehnelt cylinder 12, an anode 13, and a first condenser lens 1.
4, the second condenser lens 15 and the deflection coil 16 are provided, and the scanning electrode 17 is provided in the deflection coil 16 of the electron gun 2.
A cathode ray tube 18 for observation is connected to each of the scanning electrodes 17, and an electron beam detector 4 is connected to the cathode ray tube 18. According to the electron gun 2 having the above configuration, the electron beam can be irradiated to a desired position on the sample surface 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. The electron dose obtained by the above 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, the 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). To do. Then, the sample surface is excited to emit a fluorescent X-ray (or a characteristic X-ray) and a secondary electron beam, but at a predetermined X-ray extraction angle θt (0 to several degrees, preferably 4 degrees 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 X-ray total reflection angles (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 surface atomic arrangement structure. Further, since a secondary electron beam is also generated from the surface of the sample 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 in degrees, ρ is the density (g / cm ³ ) of the substance to be reflected, 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 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 °. Thus, 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 it is basically 4 ° or less.

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

Further, a cylindrical support port 25 is provided on the side wall 23 of the vacuum container 20 in a protruding manner, and the energy dispersive type X is provided at the tip of the support port 25 via flange plates 26 and 27.
A line detector 28 is attached. This energy dispersive X-ray detector 28 includes a tank 29 for storing liquid nitrogen.
And a probe 30 protruding in an L-shape from the bottom of the tank 29, and an auxiliary pipe 3 covering the outer periphery of the probe 30 on the base end side.
1 and a flange plate 27 fixed to the auxiliary pipe 31, and the flange plate 27 serves as a support port 25.
A preliminary chamber 32 is formed inside the auxiliary pipe 31 by being bolted to the side flange 26, and the preliminary chamber 32 communicates with the support port 25 side via the 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 vacuum exhausted. The probe 30 has a window 34 made of Be or an organic thin film attached to the tip thereof, and the semiconductor X-ray detector 8 for FET and the FET 9 for X-ray measurement are housed inside the window 34.

Inside the support port 25, a cylindrical bellows member 35 made of metal such as stainless steel is provided in the vacuum container 20.
Of the Be-shaped window portion 36 at the tip of the bellows member 35.
Is provided. On the other hand, on the inner bottom of the vacuum container 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 is used for the raw material
0 is accommodated, a deflection electron beam irradiation device 41 is provided below the crucible 39, the irradiation direction of the electron beam is deflected to be curved, the raw material 40 is irradiated, and the raw material 40 is evaporated to form a film on the sample 1. You can do it. The vapor deposition 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, a gas feeder 43 consisting of an annular pipe is provided.
The gas supply device 43 is provided with a gas supply source 4 such as an oxygen cylinder via a connecting pipe 44 that penetrates the side wall 23 of the vacuum container 20.
Connected to 5. The gas supply device 43 is formed by forming a plurality of through holes on the upper surface of an annular pipe along the circumferential direction thereof, and the gas emitted 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 container 20.
An electron gun 2 shown in FIGS. 1 and 2 is attached to the electron gun 7, and the electron gun 2 can irradiate the sample 1 at the bottom of the sample holder 22 with an electron beam (energy particles).

The apparatus of the present invention will be described in more detail below with reference to FIGS. 5 to 10, in FIG.
~ The same components as those shown in Fig. 4 are designated by the same reference numerals, and the description thereof will be omitted. In the vacuum container 20 of this embodiment, as shown in FIG.
1, 52, 53, 54, 55 are projected in various directions so that various devices can be attached.

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

C-shaped slide pieces 65 as shown in FIG. 8 are formed on both sides of the outer periphery of the slide base 61, and the slide base 61 is sandwiched between the slide pieces 65, 65 to sandwich the flange plate 27. It is movably engaged along 27. An adjusting bolt 66 is pierced through each slide piece 65, and each adjusting bolt 66 is rotatably provided with its tip abutting the outer peripheral portion of the flange plate 27. On the surface of the slide base 63 on the guide rail 62 side, a concave curved guide surface 67 having a shape matching the guide rail 62 is formed, and the slide base 63 can move along the guide rails 62, 62. It is like this. In addition, an adjusting bolt 70 is penetrated through the protruding portion 68 protruding from the slide mount 61.
Is rotatably provided with its tip abutting on the side of the slide base 63.

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

The protective tube 71 is formed in such a size that the probe 30 of the energy dispersive X-ray detector 3 can be housed therein, and the base end side of the protective tube 71, that is, the outer surface side of the slide base 63 is energized. A support frame 77 for fixing the distributed X-ray detector 3 is provided. Although not shown in FIG. 8, an energy dispersive X-ray detector including a probe 30 is provided with a pipe connecting portion for connecting to the vacuum exhaust device 33 on the proximal end side of the protective tube 71. When the probe 3 is attached to the flange plate 27 and the probe 30 is inserted into 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 preparatory chamber 32 are separated by the vacuum exhaust device 33. It can be evacuated. That is, as shown in FIG. 3, the inner surface of the protective tube 71 and the probe 3 are
A connecting chamber 79 is formed by the auxiliary chamber 78 and the auxiliary chamber 32 which are surrounded by the outer surface of 0.

The support base 77 is supported by a moving base 81 via a spring 80 as shown in FIG. 10, and the moving base 81 is supported by a base 83 via an X-shaped expansion / contraction mechanism 82. In addition, the expansion / contraction mechanism 82 uses the adjustment bolt 84
The vertical position can be adjusted freely.

Next, the case where the surface analysis is performed using the apparatus having the above-mentioned structure will be described. In order to analyze the sample 1 having the thin film H formed on the surface thereof, the inside of the vacuum container 20 is evacuated after the sample 1 is stored in the vacuum container 20. Further, the probe 30 of the energy dispersive X-ray detector 3 is connected to the protection tube 7
1 and the supporting frame 77 supports the entire energy dispersive X-ray detector 3. Further, the inside of the auxiliary chamber 32 around the probe 30 and the protection tube 71 is evacuated by the vacuum exhaust device 33. In this state, the electron gun 2 irradiates the surface of the sample with an electron beam at a predetermined incident angle. This angle of incidence is
It is preferably 4 ° or less. This incident angle is also related to the thickness of the thin film H on the surface of the sample, but the smaller the incident angle, the smaller the amount of penetration of the electron beam. Therefore, the incident angle can be applied to the thinner thin film H.

That is, the surface portion of the sample to 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 liquid droplet-like penetration does not occur in the sample 1, only the thin film H portion is excited, and the characteristic X-ray and secondary electron beam peculiar to the components of the thin film H are emitted.

Here, the scanning electrode 17 causes the deflection coil 16 to move.
The secondary electron beam can be sequentially detected by the electron beam detector 4 by adjusting the angle .alpha. To deflect the electron beam, and an enlarged image of the sample surface portion can be displayed on the cathode ray tube 18. The image obtained here on the cathode ray tube 18 is equivalent to that obtained from a conventional scanning electron microscope.

Further, fluorescent X-rays (characteristic X-rays) are emitted from the excited thin film H as shown in FIG. However, when the electron beam is made incident on the sample 1 at a shallow angle of 4 ° or less, the liquid droplet-like recessed portion with respect to the base material B which has conventionally been generated does not occur, and the generated characteristic X-ray is It sharply increases at a predetermined extraction angle (total reflection angle of characteristic X-rays) of 4 ° or less. By extracting the characteristic X-rays with the energy dispersive X-ray detector 3 at this angle, the characteristic X-rays suitable for the components of the thin film H can be specified,
Accurate surface analysis can be performed.

By the way, 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 adjusting bolt 70 shown in FIG. 8 is rotated,
Since the tip portion of the adjusting bolt 70 presses the side surface portion of the slide base 63, the slide base 63 is guided by the guide rails 62 and 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
Since it is supported by 7, the energy dispersive X-ray detector 3 tilts together with the slide base 63. Thereby, 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 tilt 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 adopting a complicated structure as shown in
The beam detector 3 is supported by a tank 29 in which the energy dispersive X-ray detector 3 is filled with liquid nitrogen for cooling.
Since the probe 30 is heavy and the structure of the probe 30 is complicated and the device cost is high, it is necessary to accurately 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 performing the analysis of the sample 1, the vacuum evacuation device 33 shown in FIG. 3 is operated to evacuate the space around the preliminary chamber 32 and the probe 30 to thereby evacuate the characteristic X generated from the sample. Since the rays can be incident on the semiconductor X-ray detection unit 8 of the probe 30 through the vacuum portion and the windows 34 and 36 made of Be or organic thin film, absorption of characteristic X-rays on the way can be suppressed as much as possible. . On the other hand, the probe 30
1.7k if there is an air layer between the tip of sample and sample 1
Since characteristic X-rays having an energy of eV or less are absorbed or attenuated, C, N, and O which can be analyzed only from characteristic X-rays of 1.7 keV or less by evacuation as described above. And F, Ne, Na, Mg and Al can be accurately analyzed. For elements having a larger atomic number than the above elements, in addition to Kα rays, Kβ rays,
Since Lα rays, Lβ rays, Lγ rays, M rays, and the like are generated, it is possible to utilize appropriate characteristic X-rays for each element for analysis.

FIG. 12 shows another embodiment of the device of the present invention. The apparatus of this example has a configuration in which a fluorescent plate 90 is added to the apparatus of the above-described embodiment. A part of the electron beam applied to the sample 1 from the electron gun 2 is diffracted on the sample surface and reflected. If the fluorescent plate 90 is installed in the radiation direction of the reflected electron beam, a pattern peculiar to the reflected high-speed electron beam can be recorded. Since this pattern is a diffraction pattern peculiar to the crystal structure on the sample surface, it can be effectively used for analysis of the sample 1 by analyzing this pattern.

Therefore, by providing the fluorescent plate 90, a magnified image by the electron beam detector 4 can be obtained, and component analysis by the energy dispersive X-ray detector 3 can be performed, and at the same time,
With the fluorescent plate 90, a diffraction pattern of a reflected high-speed electron beam can be obtained, and the sample 1 can be comprehensively analyzed from three surfaces. The fluorescent plate 90 can be easily attached to the vacuum container 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 the 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. The composition analysis data of this oxide superconducting thin film by IPC (inductively coupled plasma) emission analysis shows that Y: Ba: Cu = 1:
It has been found that the composition is 1.9: 2.8. After setting the internal pressure of the vacuum container to 1 × 10 ⁻⁷ Torr, an electron beam having an energy of 20 keV is incident on the surface of the sample at incident angles (θg) of 4 °, 11 °, and 90 °, and the energy is increased. The extraction angle (θg) of the dispersive X-ray detector is 4
The analysis was carried out by setting the angle to less than 0, 5 to 8 and 10 to 13, respectively.

The above results are shown in FIGS. Figure 1
In the case of θg = 4 ° shown in 3, the Mgkα ray of the substrate MgO is not observed at all, and only the characteristic X-rays from the YBa ₂ Cu ₃ O _x thin film are formed, and the superconducting thin film is configured without detecting the characteristic X-rays of the substrate. Only the characteristic X-rays of the element could be captured very clearly. In the field of analysis of such an oxide superconducting thin film, there is no example of clearly capturing the characteristic X-ray of only the oxide superconducting thin film, so it can be said that this is a very meaningful analysis result. In addition, in FIG.
AlKα ray is detected, but it is considered to be characteristic X-ray from Al of the sample holder part made of Al.
The lines are believed to be characteristic X-rays 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 X-ray used in the present invention may be in the range of 11 ° or less. It should be noted that the incident angle at which the amount of penetration of X-rays into the substrate can be suppressed to about several thousand angstroms (that is, 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 15 ° or less. Further, by detecting the secondary electron beam separately from the above-mentioned component analysis result, it was possible to obtain an enlarged image equivalent to that of the conventional scanning electron microscope.

In the case of θg = 11 ° shown in FIG. 14, a slight amount of electron beam diving occurs, so Mgk of MgO of the substrate
Although some α-rays are generated, the intensity of the characteristic X-rays from the YBa ₂ Cu ₃ O _x thin film is also strong, so there is no great obstacle in conducting the composition analysis of the thin film. Θg = shown in FIG.
In the case of 90 °, the intensity of MgKα ray of MgO of the substrate is high, and the intensity of characteristic X-ray from the YBa ₂ Cu ₃ O _x thin film is very weak. With this, the composition analysis of the thin film cannot be performed using the characteristic X-ray.

(Test Example 2) An Au thin film having a film thickness of 50 Å was formed on the (100) plane of a Si substrate,
This was analyzed by the same method as above. However, the incident angle θ
g is set to 4 °, X-ray extraction angle θt is set to 0 to 3 °, θt
Was set to 5 to 8 ° and θt was set to 10 to 13 °. The result is shown in FIG. As is clear from the results shown in FIG. 16, the X-ray extraction angle θt is set to AuM.
Line total reflection angle θc (AuM-Si) = 0 near 0.81 °
When the angle is set to ˜3 °, the characteristic X-ray M line of the Au thin film is the largest with respect to the Si Kα line.

A film thickness of 125 is formed on the (100) plane of the Si substrate.
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 °, and θt is 5 to 8 °.
The measurement was performed by setting θt 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 the X-ray total reflection angle θc.
When (AuM-Si) is set to 0 to 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. It is clear from FIGS. 16 and 17 that the characteristic X-ray of the thin film having the same intensity as the characteristic X-ray of the substrate can be detected if the thickness of the thin film to be analyzed is about 100 angstrom. .

[0047]

As described above, according to the present invention, the surface of a sample can be excited by irradiating the surface with an electron beam from an electron gun to emit a fluorescent X-ray and a secondary electron beam. Therefore, by detecting the X-rays by the energy dispersive X-ray detector and detecting the secondary electron beam by the electron beam detector,
An enlarged image of the sample surface can be obtained at the same time by the component analysis of the sample by the line analysis and the secondary electron beam analysis. Therefore, there is an effect that it is possible to carry out an analysis, which is not possible with the conventional analysis apparatus, that is, the component analysis of the portion can be performed while looking at the enlarged image of the sample analysis portion.

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

Further, according to the apparatus including the energy dispersive X-ray detector, the electron beam detector and the fluorescent plate, the diffraction pattern of the reflected electron beam from the sample can be obtained by the fluorescent plate, and the electron beam detector can be obtained. It is possible to obtain a magnified image by means of the energy dispersive X-ray detector, and it is possible to analyze the sample comprehensively from the three analysis results.

Further, in the case where the energy dispersive X-ray detector is detachably attached to the vacuum container via the connection chamber, an air layer is interposed between the energy dispersive X-ray detector and the sample. Since an energy dispersive X-ray detector can be used without a
Even a line can be detected without being attenuated or absorbed. That is, it becomes possible to accurately analyze C, N, O, F, Ne, Na, Mg, and Al that can be analyzed only from characteristic X-rays of 1.7 keV or less. Moreover, the energy dispersive X-ray detector can be removed without breaking the vacuum condition of the vacuum container by releasing the vacuum condition only in the preliminary chamber, and the expensive energy dispersive X-ray detector can be used in a plurality of vacuum containers. You will be able to share.

[Brief description of drawings]

FIG. 1 is a schematic view showing the arrangement of essential parts 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 an embodiment of the present invention.

FIG. 4 is a schematic diagram showing the overall configuration of the vacuum container of the embodiment shown in FIG.

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

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

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

FIG. 8 is a cross-sectional view showing a support structure of the probe of the above-mentioned 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 the sample surface and an excited state of the sample surface portion 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 diagram showing a result of surface analysis of the first sample by the device of the present invention.

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

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

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

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

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

[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 detection part, 20 ... Vacuum container, 32 ... Preliminary chamber, 75 …
Preliminary room, 76 ... Connection room, θg ... Electron beam incident angle, θ
t ... X-ray extraction angle.

   ─────────────────────────────────────────────────── ─── Continued front page    (71) Applicant 000002255             Showa Electric Wire & Cable Co., Ltd.             2-1-1 Oda Sakae, Kawasaki-ku, Kawasaki-shi, Kanagawa             issue (72) Inventor Toshio Usui             Foundation law, 1-14-3 Shinonome, Koto-ku, Tokyo             International Superconductivity Technology Center             Conducting Engineering Laboratory (72) Inventor Yuji Aoki             Foundation law, 1-14-3 Shinonome, Koto-ku, Tokyo             International Superconductivity Technology Center             Conducting Engineering Laboratory (72) Inventor Masayuki Kamei             Foundation law, 1-14-3 Shinonome, Koto-ku, Tokyo             International Superconductivity Technology Center             Conducting Engineering Laboratory (72) Inventor Tadataka Morishita             Foundation law, 1-14-3 Shinonome, Koto-ku, Tokyo             International Superconductivity Technology Center             Conducting Engineering Laboratory

Claims (6)

[Claims] 1. An electron gun for injecting an electron beam on the surface of a sample, and 2 from a sample surface portion excited by the electron beam being incident.
An electron beam detector for detecting a secondary electron beam and an energy dispersive X-ray detector arranged for the sample so as to detect the fluorescent X-rays from the excited sample surface portion in the vicinity of the total reflection angle of the X-rays. And a surface analysis device. 2. A vacuum container for housing a sample, and an electron gun connected to the vacuum container for injecting an electron beam to the sample,
An electron beam detector connected to the vacuum container to detect a secondary electron beam generated from the sample, and energy to detect fluorescent X-rays from the excited sample surface portion in the vicinity of the total reflection angle of X-rays. A surface analysis device comprising a distributed X-ray detector. 3. A vacuum container for accommodating a sample, and an electron gun connected to the vacuum container for injecting an electron beam onto the sample,
An electron beam detector connected to the vacuum container to detect a secondary electron beam generated from the sample; an energy dispersive X-ray detector to detect fluorescent X-rays from the excited sample surface portion; A surface analysis device, comprising: a fluorescent plate that fluorescently displays an electron beam diffracted and reflected by the excited sample surface portion. 4. The surface analyzer according to claim 2 or 3, wherein a connection chamber that can be evacuated to vacuum is formed in the vacuum container separately from the inside of the vacuum container, and the energy dispersion type is provided through the connection chamber. A surface analysis device having an X-ray detector detachably attached. 5. The surface analyzer according to claim 1, 2, 3 or 4, wherein an incident angle of an electron beam with respect to a sample is 1
A surface analysis device characterized by being set at 5 ° or less. 6. The surface analyzer according to claim 1, 2, 3 or 4, wherein an incident angle of an electron beam with respect to a sample is 4
The surface analysis device is characterized in that the extraction angle of fluorescent X-rays from the sample is set to 4 ° or less.