JPS63281341A - X-ray analyzing device provided with energy dispersion type x-ray spectroscope - Google Patents

Abstract

PURPOSE:To prevent the lowering of X-ray detection efficiency even when a sample is moved up and down in the direction of an electron ray optical axis by providing a means for automatically moving up and down the X-ray detector of an energy dispersion type X-ray spectroscope following the up and down movement of the sample. CONSTITUTION:A control part 20 rotates a motor 16 for moving a stage while firstly controlling a motor driving power source 19 based on a sample moving signal from an operation part 21. Thereby, the sample stage 5 screwed in a rotary axis 16a moves by a specified distance. Accordingly, the sample 4 moves from a point A to a point A'. Further, the control circuit 20 controlls the motor driving power source 19 to rotate a motor 17 for moving a detector based on the sample moving signal and moving a stage 6 for moving the detector connected to a rotary axis 17a by a distance covered by the moved sample 4. Accordingly, an X-ray detector 13 moves from a point B to a point B'. Consequently, when the position of the sample is moved from a point A to a point A' for analyzing, the position of the X-ray detector 13 moves from the point B to the point B' following the movement of this sample so that the amount of the incident X-rays is not reduced even when the sample is moved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an X-ray analyzer, and particularly relates to an X-ray analyzer equipped with an energy dispersive X-ray spectrometer that moves up and down following the up and down movement of a sample. .

[Prior art] In an X-ray analyzer such as an X-ray microanalyzer, a certain area of a sample is scanned with an electron beam, and the energy of the characteristic X-rays generated from the sample is collected using an energy dispersive (abbreviated as EDS) for qualitative and quantitative analysis of samples.

In such an X-ray analyzer, X-ray quanta generated from a sample are detected by a semiconductor X-ray detector (hereinafter referred to as an X-ray detector), and the energy is discriminated by a multi-channel analyzer. Qualitative or quantitative analysis is performed by displaying the acquired spectral data and count values on a display device.

[Problems to be Solved by the Invention] Incidentally, in such an X-ray analyzer, as shown in FIG. When analyzing the sample S by moving it up and down in the direction of the electron beam optical axis Z, for example, the sample S
When the position is moved from A to A', the solid angle θ1 of the X-rays incident on the window Dw of the X-ray detector changes to θ2. Therefore, there is a drawback that the amount of X-rays incident on the X-ray detector is reduced and the X-ray detection efficiency is lowered.

The present invention has been made in view of the above points, and is an X-ray spectrometer equipped with an energy dispersive X-ray spectrometer that can prevent a decrease in X-ray detection efficiency even when the sample is moved up and down in the direction of the electron beam optical axis.
The purpose is to provide a line analysis device.

[Means for Solving the Problems] In order to achieve the object, the present invention provides a sample stage that holds a sample and is movable up and down in the direction of the electron beam optical axis, and a sample stage that can move up and down in the direction of the electron beam optical axis. In an apparatus equipped with an energy-dispersive X-ray spectrometer that detects X-rays, an X-ray detector of the energy-dispersive X-ray spectrometer is automatically moved up and down following the vertical movement of the sample. It is characterized by having the means.

[Example] Embodiments of the present invention will be described in detail below based on the drawings.

In FIG. 1 showing an embodiment of the present invention, 1 is a mirror body forming a sample chamber of an electron microscope, etc., 2 is an objective lens,
3 is an electron beam, and 4 is a sample to which the electron beam 3 is irradiated. 5
is a sample stage for moving the sample 4. 6 is a stage for moving the detector, and an EDS 7 is movably placed on the stage. 8 is a moving screw for moving the EDS 7 in the direction of the arrow, and an operating handle 9 is attached to the moving screw 8. By rotating this operating handle 9, the EDS 7 is transferred to the sample 4.
It can be moved closer to sample 4 or further away from sample 4.

The EDS 7 also includes a liquid nitrogen container 10, a support stand 11, a heat conduction rod 12 thermally connected to the refrigerant tank, and the heat conduction rod 1.
The X-ray detector 13 is cooled by the X-ray detector 2, the protective pipe 14 is arranged to cover the X-ray detector 13, and the protective pipe 14 passes through the detector moving stage 6. It is inserted into the mirror body 1, and its tip reaches close to the sample 4. Figure 2 shows X-ray detector 1
3 is an enlarged view of the vicinity of the X-ray detector 1 of the protective pipe 14.
There is an X-ray passage hole 14 in the part facing 3. a is pierced,
The X-ray passage hole 14a is covered with a thin film 15 made of, for example, beryllium (Be) for transmitting X-rays from the sample, and the inside of the protection pipe 14 is kept in a vacuum. 16 is a stage moving motor for moving the sample stage 5 up and down in the direction of the electron beam optical axis, and 17 is a detector moving motor for moving the detector moving stage 6 up and down. The motor 17 is fixed to the mirror body 1, and the motor 17 is attached to a stand 18. 19 is a motor drive power source, and 20 is a control section that controls the motor drive power source 19 based on a signal from an operation section 21. 22 is an O-ring for maintaining airtightness between the through hole of the detector moving stage 6 and the protection pipe 14, and 23 is an O-ring for maintaining the vacuum in the sample chamber when the detector moving stage 6 moves up and down. An O-ring 24 is used to maintain airtightness between the mirror body 1 and the motor mounting base 18. 25 is a rotating shaft 16a of the motor 16 for moving the stage.
26 is a lid for the sample chamber, and 27 is an O-ring for maintaining a vacuum inside the mirror body 1 when the mirror body 1 rotates.

In the apparatus configured in this manner, the X-rays generated by irradiating the sample 4 with the electron beam 3 are transmitted through the window 15, further through the X-ray passage hole 14a, and detected by the X-ray detector 13.

By the way, when a sample movement operation is performed using the operation section 21, a sample movement signal from the operation section 21 is inputted to the control section 20. The control section 20 first controls the motor drive power source 19 to rotate the stage movement motor 16 based on the sample movement signal from the operation section 21 . As the motor 16 rotates, the sample stage 5, which is screwed onto the rotating shaft 16a, moves by a specified distance. Therefore, the sample 4 moves from point A to point 81, for example, as shown in FIG. Further, the control circuit 20 controls the motor drive power source 19 based on the sample movement signal to rotate the detector movement motor 17,
The detector moving stage 6 connected to the rotating shaft 17a is moved by the distance that the sample 4 has moved. Therefore, the X-ray detector 13 moves from point B to one point B.

Therefore, in the apparatus configured in this way, when the position of the sample 4 is moved from point A to point 81 for analysis, the position of the X-ray detector 13 is also changed from point B to point B to follow this movement of the sample. Therefore, the X-ray extraction angle θ does not change, and the solid angle θ1 of the X-rays incident on the X-ray detector 13 also does not change. Therefore, the amount of X-rays incident on the X-ray detector 13 does not decrease even if the sample moves, and therefore it is possible to prevent the X-ray detection efficiency from decreasing due to sample movement.

[Effects of the Invention] As detailed above, according to the present invention, even when the sample is moved up and down in the direction of the electron beam optical axis, the X-ray detector is made to follow the up and down movement of the sample, and the X-ray detection By moving the X-rays so that the solid angles of the X-rays incident on the instrument are the same,
An X-ray analyzer equipped with an energy dispersive X-ray spectrometer that prevents a decrease in X-ray detection efficiency due to sample movement is provided.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the structure of an embodiment of the present invention, FIG. 2 is an enlarged view of the essential parts of the apparatus of the embodiment, FIG. 3 is a diagram for explaining the present invention in detail, and FIG. FIG. 2 is a diagram for explaining a conventional device. 1: Mirror body of electron microscope, etc., 2: Objective lens, 3: Electron beam, 4: Sample, 5: Sample stage, 6: Detector movement stage, 7: EDS18: Movement screw, 9: Operation handle, 10 : Liquid nitrogen container, 11: Support stand, 12: Heat conduction rod, 13: Semiconductor X-ray detector, 14: Protective pipe, 15:
Window, 16: Stage movement motor, 17: Detector movement motor, 18: Motor mounting base, 19: Motor drive power supply, 20: Control unit, 21: Operation unit, 22.23
゜24.25.27: 0 ring, 26: Sample chamber lid.

Claims (1)

[Claims] In an apparatus comprising a sample stage that holds a sample and is movable up and down in the direction of the electron beam optical axis, and an energy dispersive X-ray spectrometer that detects X-rays from the sample as the sample is irradiated with the electron beam, An X-ray spectrometer equipped with an energy dispersive X-ray spectrometer, characterized in that it is equipped with means for automatically moving an X-ray detector of the energy dispersive X-ray spectrometer up and down in accordance with the vertical movement of a sample. Line analyzer.