JPS63261146A - X-ray analysis instrument - Google Patents

Abstract

PURPOSE:To permit X-ray analysis even if the incident quantity of X-rays entering an energy dispersion type X-ray spectroscope (EDS) at the max. stroke is large by providing an X-ray incidence limiting stop in front of said spectroscope and operating the spectroscope from the atm. side. CONSTITUTION:Electron rays 3 are projected to a sample 3 disposed in a body 1 of an electron microscope or the like to generate X-rays. A wavelength dispersion type X-ray analyzer (WDS) and EDS 8 are provided in the body 1 in order to spectrally split the X-rays. A semiconductor X-ray detector of the EDS 8 is mounted to the front end of a heat conductive bar 12 protected in a protective pipe 14 and is charged into the body 1. The pipe 14 is moved by the operation of an operation handle 10 from the atm. side by a moving stage 7 while the vacuum in the body 1 is maintained. An incident X-ray variable stop mechanism 15 is mounted to the front face of the X-ray detector 13 so as to move integrally with the pipe 14. The incident X-ray quantity by the mechanism 15 is changed over by a knob 16 mounted to the atm. side thereof while the vacuum in the body 1 is maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an X-ray analyzer, and more particularly to an X-ray analyzer equipped with a wavelength-dispersive X-ray spectrometer and an energy-dispersive X-ray spectrometer.

[Prior Art] In an X-ray analyzer such as an X-ray microanalyzer, an electron beam is irradiated onto a minute area of a sample, and the X-rays generated from the sample are separated to obtain an X-ray spectrum. This type of X-ray analysis device uses a wavelength dispersive X-ray spectrometer (hereinafter abbreviated as WDS), which has excellent wavelength resolution, and a wavelength-sweeping system that mechanically moves a spectroscopic crystal, which has inferior wavelength resolution. The laboratory is equipped with an energy dispersive X-ray spectrometer (hereinafter abbreviated as EDS) capable of X-ray spectroscopy, and is used for qualitative and quantitative analysis of samples.

In such an X-ray analyzer, when performing X-ray analysis using the former WDS, an irradiation current that is approximately 10 times larger than when performing X-ray analysis using the former EDS is required.

Therefore, when performing X-ray analysis using a WDS, if the amount of X-ray signals from the sample *31 incident on one EDS is too large, the X-ray detector becomes saturated and cannot be detected. Therefore, in the conventional device a3, one EDS
When X-ray analysis is performed by WDS with a detector moving mechanism installed on the EDS side, the distance between the X-ray detector and the sample is adjusted by the detector moving mechanism, and X-ray detection on the EDS side is performed. The amount of X-rays that enter the device is limited.

[Problems to be solved by the invention] By the way, in the conventional device configured as described above, the EDS
The distance between the sample and the X-ray detector is 11111 times longer than the moving distance of the side X-ray detector, that is, the maximum stroke of the detector moving mechanism.
-! Therefore, if the amount of incident X-rays is large in the state of maximum stroke, it is not an X-ray analysis.

The present invention has been made in view of the above points, and is based on the WDS and ED.
In an apparatus for X-ray analysis of 1 by S, the ED
An X-ray incidence limiting diaphragm is provided in front of the X-ray detector side of S to limit the amount of incident X-rays from the sample, and by operating the incidence limiting diaphragm from the atmosphere side, the X-rays enter at a maximum stroke of 1~. It is an object of the present invention to provide an X-ray analysis device that enables X-ray analysis even when the amount of incident X-rays is large.

Means for Solving Problem 1 1 The present invention for achieving the above object includes a means for generating X-rays by irradiating a sample placed in a vacuum mirror body with an electron beam, and a method for generating X-rays. A wavelength-dispersive X-ray analyzer and an energy-dispersive X-ray spectrometer are arranged in the vacuum mirror for spectroscopy, and the semiconductor X-ray of the energy-dispersive X-ray spectrometer is provided.
The line detector is attached to the tip of a heat conductive rod protected within the protective pipe (pull-C) and inserted into the vacuum mirror body,
In order to adjust the distance between the sample and the X-ray detector, a moving mechanism is provided for moving the protective pipe in the insertion direction by operating from the atmosphere side while maintaining the vacuum inside the mirror body. An incident xfgA variable aperture mechanism mounted on the front surface of the X-ray detector so as to move integrally with the protection pipe, and an input xfgA variable aperture mechanism installed in the X-ray analyzer, and a l that changes the amount of incident X-rays by the aperture mechanism. A pull-out operation means is attached to the atmosphere side, and the drive force from the operation means is transmitted to the aperture m'M4 while maintaining the vacuum inside the mirror body, and it moves integrally with the protection pipe. It is characterized by being equipped with a transmission mechanism.

[Example 1 Embodiments of the present invention will be described in detail below with reference to the drawings.

In FIG. 1 showing an embodiment of the present invention, 1 is a mirror body such as an electron microscope, 2 is an objective lens, 3 is an electron beam, and 4 is a mirror body such as an electron microscope.
is a sample to which the electron beam 3 is irradiated.

5 is a sample stage for moving the sample 4.

6 is a spectroscopic crystal for spectrally dispersing the X-rays from the sample 4; the X-rays spectrally separated by the spectroscopic crystal are detected by an X-ray detector (not shown), and subjected to X-ray analysis by a counting circuit. 7 is a stage for moving the detector, 7A is a guide rail, and the EDS 8 is movably mounted on the stage. 9 is a moving screw for moving the EDS 8, and an operating handle 10 is attached to the moving screw 9. By rotating this operating handle 10, the EDS 8 is moved. can be moved closer to the sample 4 or moved away from the sample 4, and in this case the maximum speed of the X-ray detector is 1~
Rotor included. The EDS 8 also includes a liquid nitrogen container 11 having a refrigerant tank inside, a support stand 11A, a heat conduction rod 12 thermally connected to the refrigerant tank, an X-ray detector 13 cooled by the heat conduction rod 12, A protective pipe 14 is arranged to cover the periphery of the X-ray detector 13, and a cylindrical X-ray incidence limiting aperture 15 is rotatably attached to the support base 11A.
, an operation knob 16 for rotating the X-ray incidence limiting diaphragm 15, and the like. FIG. 2 is an enlarged view of the vicinity of the X-ray detector 13, and the portion of the protective pipe "14 facing the X-ray detector 13 has an X-ray as shown in FIG.
An X-ray passing hole 14a is bored, and the X-ray passing hole 14. In a, for example, berylicomb (Be) is used to transmit X-rays from the sample. The window 17 consisting of a membrane is stretched ('j-
The inside of the protection pipe 14 is kept in a vacuum. Nu,
An X-ray passage hole 15a, as shown in FIG. The X-ray incidence limiting diaphragm 15 can be rotated by tilting the operating knob 1G in a direction perpendicular to the plane of the paper. Figure 4 (b) shows a state in which the X-ray incidence limiting diaphragm 15 is not rotated Δ, and in this case, the X-ray passage hole formed by the X-ray passage hole 15a and the X-ray passage hole 14a is The area is A, which is the minimum. Furthermore, when the X-ray incidence limiting diaphragm 15 is rotated 90 degrees from this state using the operating knob 16, the X-ray passage hole 15a shown in FIG. X-ray passing hole 14a
The area of the X-ray passing hole formed by and is the maximum of 8- as shown in FIG. 4(b).

18 is an O-ring for maintaining airtightness between the X-ray incidence limiting diaphragm 15 and the protection pipe 14; one is an O-ring for maintaining the vacuum inside the mirror body 1; X-ray incidence limiting aperture 15 while maintaining the vacuum inside the body 1
You can rotate and move it. Reference numeral 20 is an O-ring for maintaining the vacuum inside the mirror body 1.

In the apparatus configured in this way, the XIM generated by irradiating the sample 4 with the electron beam 3 passes through the X-ray passing holes 15a and 14a, and further passes through the window 17 to the X-ray detector 13.
detected by. By the way, X-ray passing hole 1'I-
The area of the X-ray passage hole formed by the X-ray passage hole 15a and the X-ray passage hole 15a can be varied by the operation knob 16 as described above.

Therefore, when performing X-ray analysis using WDS, if the amount of X-rays from the sample that enters the X-ray detector 13 is too large, the X-ray entrance aperture 15 can be rotated using the operation knob 16. The amount of incident signals of X-rays incident on the X-ray detector 13 is limited.

Even with this operation, if the X-ray detector 13 becomes saturated and cannot be detected, the distance between the X-ray detector 13 and the sample 4 can be adjusted by rotating the operating handle 10. Even if there are too many particles to be detected, X-ray analysis can be performed using FDS.

FIG. 5 is a sectional view of a main part of another embodiment of the present invention, and in this embodiment, the same components as those of the embodiment shown in FIG. 1 are given the same numbers and their explanations are omitted. In FIG. 5, reference numeral 21 denotes a protection pipe arranged to cover the X-ray detector 13, and the protection pipe 21 is rotatably attached to the support base 12 as shown in FIG. This protection pipe 2 can be opened by operating the operation knob 22.
1 can be rotated. Also, this protection pipe 21
and the center of the X-ray detector 13 are eccentric, and the center of the
As shown in FIG. 7, X-ray passing holes 21a, 21b, and 21c having different diameters are bored in the portion facing the ray detector 13, and the window 17 is attached to the X-ray passing holes.
It is being Therefore, in a device configured in this way,
By operating the operating knob 22, the X-ray passing holes 21a, 2
X-ray detector 13 connects either X-ray passing hole 1b or 21c to
By rotating it so that it is located at the center of the X-ray detector 13, it is possible to similarly limit the amount of incident X-ray signals entering the X-ray detector 13 and perform X-ray analysis.

FIG. 8 is a sectional view of a main part of still another embodiment, and in this embodiment, the same components as those of the embodiment shown in FIG. 1 are designated by the same numbers and their explanations are omitted.

In FIG. 8, 23 is a protection pipe for protecting the X-ray detector 13, and the protection pipe 23 is attached to the support base 11A. Further, as shown in FIG. 9, an X-ray passage hole 23a is bored in the portion of the protective pipe 23 facing the X-ray detector 13, and the window 17 is inserted into the X-ray passage hole. 24 is a metal fitting that supports the rotation support rod 25, one end of the support rod 25 is rotatably supported by the metal fitting, and an X-ray incidence limiting aperture plate 26 is attached to the other end. Also, as shown in FIG. By rotating the rotary support rod 25, any one of the X-ray passing holes 26a, 26b, and 26C can be arranged in front of the X-ray passing hole 23a. Even with this apparatus, it is possible to perform X-ray analysis by limiting the amount of X-rays incident on the X-ray detector 13, as in the apparatus of the above-described embodiment.

It should be noted that the embodiments described in "2" are merely illustrative and may be modified.

For example, in the embodiment shown in FIG.
Although we have explained the case where the minimum area Δ and the maximum area Δ′ of the X-ray passage hole formed by a and the X-ray passage hole 14a are changed,
By selecting the rotation angle of the X-ray incidence limiting diaphragm 15 in the range of 0 to 90 degrees, the area of the X-ray passing hole is adjusted to an area between the minimum area A and the maximum area/M, and the X-ray detector 13 The amount of incident X-rays can be limited.

In addition, in the embodiment apparatus shown in FIGS. 5 and 8, three X-ray passing holes having different diameters are formed in the protective pipe 21 and the X-ray incidence limiting aperture plate 26, respectively.
It is not limited to.

[Effects of the Invention] As detailed above, according to the present invention, the wavelength dispersion type XI!
In an apparatus equipped with a spectrometer and an energy dispersive X-ray spectrometer with detector movement am, an X-ray incidence limiting aperture is placed in front of the X-ray detector side of the EDS to limit the amount of X-rays incident on the sample. The 1st X-ray is operated from the atmospheric side by providing a
A line analyzer is provided.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of the configuration of an embodiment of the present invention, Fig. 2 is an enlarged view of the main parts, Fig. 3 (a) and (exit) are diagrams for explaining the X-ray passage hole, Fig. 4 (A) and (B) are diagrams showing states in which the area of the X-ray passage hole is changed, FIG. 5 is a cross-sectional view of the configuration of another embodiment, and FIGS. A diagram for explaining an example, FIG. 8 is a sectional view of a configuration of another embodiment,
FIGS. 9 and 10 are diagrams for explaining the embodiment shown in FIG. 8. 1: Mirror body of electron microscope, etc., 2: Objective lens, 3: Electron beam, 4: Sample, 5: Sample stage, 6: Spectroscopic crystal, 7: Detector movement stage, 8: EDS, 9: Movement screw, 10
: Operation handle, 11: Liquid nitrogen container, 11A: Support stand, 12: Heat conduction rod, 13: X-ray detector, 14.21,
23: Protective pipe, 15: X-ray incidence limiting aperture, 16,2
2, 27: Operation knob, 17: Window, 18.19
:20: O-ring, 24: Metal fitting, 25: Rotation support rod, 2
6: X-ray incidence limiting aperture plate.

Claims (1)

[Claims] A means for generating X-rays by irradiating a sample placed in a vacuum mirror with an electron beam, and a wavelength-dispersive X-ray analyzer and energy dispersion located in the vacuum mirror to analyze the X-rays. type X-ray spectrometer, the semiconductor X-ray detector of the energy dispersive X-ray spectrometer is attached to the tip of a heat conductive rod protected within a protective pipe and inserted into the vacuum mirror body, An X-ray device including a moving mechanism for moving the protective pipe along the insertion direction by operation from the atmosphere side while maintaining a vacuum inside the mirror body in order to adjust the distance between the sample and the X-ray detector. In the analyzer, an incident X-ray variable aperture mechanism is attached to the front surface of the X-ray detector so as to move integrally with the protection pipe, and an incident X-ray variable aperture mechanism is attached to the atmosphere side to switch the amount of incident X-rays by the aperture mechanism. It is characterized by comprising an operating means, and a transmission mechanism configured to transmit the driving force from the operating means to the aperture mechanism while maintaining the vacuum inside the mirror body, and to move integrally with the protection pipe. X-ray analyzer.