JPS5818852A - Electron microscope having reflecting diffraction device - Google Patents

Abstract

PURPOSE:To enable a sample position from which a reflecting diffraction pattern is obtained to be easily determined by previously making the optical axis of an unscanned electron ray, which can be switched by one touch operation, to coinside with the optical axis of a scanned electron ray. CONSTITUTION:The optical axis of an unscanned electron ray is adjusted with an exclusive shaft position setting circuit so that the above optical axis passes the center of a diffraction sample chamber 1. Next, an electron ray is scanned, and the optical axis of the scanned electron ray is arranged in alignment with the center of the chamber 1 by means of a shaft position setting circuit of the scanning mode. Then, a sample 4 is inserted so as to obtain a lowly multiplied image of the entire sample 4 upon the CRT of an absorbed-electron display device. After that, an attachment table 10 is rotated so as to adjust the sample 4 to be parallel to the electron ray. By the means mentioned above, a reflecting diffraction pattern can be easily obtained by carrying out an adjustment by means of fine adjustment knobs 6 and 11 so that the position, on which the reflecting diffraction pattern of the sample 4 is desired to be obtained, coincides with the center of the CRT before thus obtained pattern is returned back to the electron ray.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electron microscope having a reflection diffraction device, and more particularly to an electron microscope having a reflection diffraction device having a positioning function suitable for determining the position of a sample by reflection diffraction.

In an electron microscope equipped with a conventional reflection diffraction device that obtains a diffraction pattern on the surface of a sample, when obtaining a reflection diffraction pattern, the sample is mounted on the reflection diffraction device at a substantially right angle, that is, approximately parallel to the electron beam, and the electron beam is The electron beam is adjusted to the center of the microscope and is applied to the surface of the sample to obtain a reflection diffraction pattern. However, since conventional equipment does not have a detection means for applying an electron beam to the sample surface, the reflection diffraction device is mechanically adjusted to the center of the electron microscope, and the reflection diffraction device is finely adjusted while working blindly. I was looking for a place where I could get a diffraction pattern. The disadvantage of this method is that it takes a lot of time to obtain a reflection diffraction pattern.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electron microscope having a reflection diffraction device that can easily determine a sample position where a reflection diffraction pattern can be obtained. .

In the present invention, the optical axis of a non-scanning electron beam, which can be switched with a single touch, and the optical axis of a scanning electron beam are made to coincide with each other by each optical axis adjustment circuit, and by scanning the electron beam, the optical axis of the scanning electron beam is aligned. The purpose is to easily determine the sample position where a reflection diffraction pattern can be obtained by adjusting the displayed sample at the center of the CRT and approximately parallel to the electron beam using a sample fine movement mechanism.

Hereinafter, embodiments of the present invention will be described.

FIG. 1 shows an embodiment of the invention.

In the figure, a reflection diffraction apparatus 100 consists of an electron microscope diffraction sample chamber 1 and a positioning device 50. Positioning device 5
The sample stage 2 of 0 is attached to the left and right fine movement shaft 3,
Sample 4 is now ready for adhesion.

Further, the longitudinal fine movement shaft 5 attached to the sample stage 2 can be changed back and forth by a fine movement knob 6, and a fine movement receiver consisting of a slider 7, a spring 8, and a spring receiver 9 is attached to the opposite part of the fine movement knob 6. is fixed. The mount 10 is fixed to the diffraction sample chamber 1 and is made of an insulating material, so that the entire reflection diffraction device is insulated from the diffraction sample chamber 1. In the above apparatus, fine movement of the sample from side to side is performed by rotating the fine movement knob 11. At this time, rotation of the left and right fine movement shaft 3 is stopped by a stopper 12 attached to the front and rear fine movement shaft 5.
The presser foot 13 is a presser foot that allows the left and right fine movement shaft 3 to be moved left and right by rotating the fine movement knob 11. The absorption electron signal extraction line 14 is attached to the longitudinal fine movement shaft 5, is insulated from the diffraction sample chamber 1, has a structure from which an absorption signal can be extracted, and is connected to an absorption electron display (not shown). A scanning coil (not shown) is attached to the top of the reflection diffraction device, and scanning signals are sent from the absorption electronic display device.

In the above configuration, the optical axis of the non-scanning electron beam is adjusted to pass through the center of the diffraction sample chamber 1 using a dedicated axis alignment circuit.

Next, the electron beam is scanned and the optical axis is aligned with the center of the diffraction sample chamber 1 using an axis alignment circuit in this mode. Next, the sample 4 is inserted and a low magnification image of the entire sample group is obtained on the CRT of the absorption electronic display device. First, the mount 10 is rotated and adjusted so that the sample is parallel to the electron beam.

In this way, the reflection diffraction pattern can be easily obtained by adjusting the fine movement knob 6.11 so that the desired position for obtaining the reflection diffraction pattern of the sample 4 is at the center of CR and T, and returning to the electron beam.

Note that the same effect can be obtained by using a normal scanning electron imager for a transmission electron microscope instead of the backscattered electron display device.

As explained above, according to the present invention, it is possible to easily determine the sample position where a reflection diffraction pattern can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

Claims (1)

[Claims] 1. An electron microscope having a reflection diffraction device for a diffraction sample chamber movable back and forth and left and right with respect to the optical axis, comprising a scanning coil above the reflection diffraction device and a display device for an absorbed electron signal from the reflection diffraction device. An electron microscope having a reflection diffraction device characterized in that: