JPH037880Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an apparatus for obtaining an electron beam reflection diffraction image.

In an electron microscope, various images can be observed in addition to a normal transmission image, and an electron beam reflection diffraction image is also observed as one of such images.

FIG. 1 shows a conventional apparatus for obtaining this electron beam reflection diffraction image. In the figure, 1 is an electron gun, 2 is a focusing lens, 3 is an objective lens, 4 is an intermediate lens,
5 is a projection lens, and 6 is a fluorescent plate. In the conventional structure having such a structure, the crossover image P of the electron gun formed by the focusing lens 2 is focused on the object plane of the projection lens 5 by the objective and intermediate lenses 3 and 4, and then the crossover image P of the electron gun is formed by the focusing lens 2. The sample 7 is placed between the projection lens 5 and the fluorescent plate 6 so that the image of this crossover image P is formed on the fluorescent plate 6, and its surface has a slight angle with respect to the optical axis C. The electron beam EB is made incident on the sample 7 along the optical axis C. When the electron beam EB is incident on the sample 7, the electron beam DB diffracted from the sample 7 is projected onto the fluorescent plate 6, and a diffraction image DP as shown in FIG. 2 is displayed on the fluorescent plate 6, for example. Ru.

However, as is clear from FIGS. 1 and 2, in the past, the electron beam diffraction image could only be displayed on a portion of the fluorescent plate 6, and the display surface was effectively used to display the diffraction image. I couldn't do that.

Furthermore, when attempting to compare the electron beam reflection diffraction image of a standard sample and the electron beam reflection diffraction image of a sample to be analyzed, it is necessary to perform troublesome work such as exchanging the sample, and it is difficult to compare both images in a short time. It is not possible to switch and make comparative observations.

The present invention solves these conventional drawbacks, allows a diffraction image to be projected over the entire display or recording surface, and
It is an object of the present invention to provide an electron beam reflection diffraction image observation apparatus that can switch and observe electron beam reflection diffraction images of different samples in a short time.

The present invention is equipped with a lens system including a final stage focusing lens for forming a crossover image of an electron beam from an electron gun on a detection surface for image display, and the final stage focusing lens and the detection surface are connected to each other. A plurality of samples are arranged substantially symmetrically with respect to the optical axis at a predetermined distance from the optical axis between the two, and the plurality of samples are arranged with respect to the optical axis direction so that the surfaces facing each other face the detection surface side. A deflector is disposed near the final stage focusing lens, and the electron beam deflected away from the optical axis by the deflector is deflected at a slight angle to the surface. In order to direct the electron beam to one of the plurality of samples, a deflection means, which is either combined with the final stage focusing lens or provided separately, is arranged to direct the sample to be irradiated with the electron beam between the plurality of samples. It is characterized by an electron beam reflection diffraction image observation apparatus equipped with a switching means for switching between the two.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

Figure 3 shows one embodiment of the present invention.
In the figure, the same components as in FIG. 1 are given the same numbers.

12 is a deflection coil, 13 is a polarity switching circuit, and 14 is a deflection power source for supplying a deflection current to the deflection coil 12. Projection lens 5 and fluorescent plate 6
Between the sample 7a to be analyzed and the standard sample 7
b is placed. These samples 7a and 7b are arranged approximately symmetrically with respect to the optical axis C at a predetermined distance from the optical axis C. The samples 7a and 7b are arranged slightly inclined with respect to the direction of the optical axis C so that the surfaces facing each other face the fluorescent plate side.

In such a configuration, the excitation intensity of each lens is adjusted to form a crossover image P of the electron gun on the fluorescent plate 6, as in the prior art described above. Next, by adjusting the current supplied from the power supply 14 and the deflection coil 12, the electron beam deflected away from the optical axis C by the deflection coil 12 is made to enter the projection lens 5. Since the projection lens 5 has a deflection effect, the electron beam EB is deflected back toward the optical axis C, but the electron beam deflected back by the projection lens 5 forms a slight angle with the surface and is analyzed. The current supplied from the deflection power supply 14 to the deflection coil 12 is adjusted so that the current is incident on the target sample 7a.

As a result, the electron beam EB enters the sample 7a and is reflected, and an electron beam reflection diffraction image is projected onto the fluorescent plate 6. Since the diffracted electron beam DB reflected from the sample 7a can be projected onto the fluorescent plate 6 with the surface of the sample 7a arranged at a larger angle than the conventional one with respect to the optical axis C, the entire surface of the fluorescent plate 6 can be can be effectively used to display an electron beam reflection diffraction image on the fluorescent plate 6.

Therefore, when attempting to display an electron beam reflection diffraction image of the standard sample 7b instead of an electron beam reflection diffraction image based on the sample 7a to be analyzed, the polarity switching circuit 13 is operated to connect the deflection coil to the deflection power source 14. 1
Reverse the direction of the current supplied to 2. As a result, the electron beam EB is deflected by the coil 12 as shown by the dotted line in FIG. 3, and then deflected by the projection lens 5 in a direction opposite to the initial direction and enters the standard sample 7b. As a result, an electron beam reflection diffraction image based on the standard sample 7b is displayed on the fluorescent plate 6 in the same manner as in the case of the sample to be analyzed.

The above-mentioned embodiment shows one embodiment of the present invention, and the present invention can be implemented with modification.

For example, in the embodiment described above, the projection lens 5 is also used as a deflecting means.
The deflection coil 12 may be disposed below the projection lens, and a deflection coil for deflecting the electron beam deflected away from the optical axis by the deflection coil 12 may also be disposed below the coil 12.

Further, in the above-described embodiments, a fluorescent plate was used as a detection surface for display, but the present invention can be similarly applied to the case where a diffraction image is projected onto a photoelectric detection surface connected to a display device.

As is clear from the above explanation, according to the present invention, not only can a diffraction image be projected by effectively using the display surface, but also by operating the switching means,
It is possible to easily switch and observe electron beam reflection diffraction images based on different samples, and it is possible to easily compare and observe the electron beam reflection diffraction image of the sample to be analyzed with that of a standard sample, etc., thereby improving the analysis performance of the sample. .

[Brief explanation of the drawing]

FIG. 1 is a diagram for illustrating a conventional device, FIG. 2 is a diagram for explaining the drawbacks of the conventional device, and FIG. 3 is a diagram for showing an embodiment of the present invention. 1: Electron gun, 2: Focusing lens, 3: Objective lens, 4: Intermediate lens, 5: Projection lens, 6: Photographic film, 7a: Sample to be analyzed, 7b: Standard sample, 12: Deflection coil, 14: Deflection power supply , 13:
Polarity switching circuit, C: optical axis, EB: electron beam, DB: diffraction electron beam.

Claims (1)

[Scope of utility model registration request] A lens system including a final stage focusing lens for forming a crossover image of the electron beam from the electron gun on a detection surface for image display is provided, and a lens system is provided between the final stage focusing lens and the detection surface. A plurality of samples are arranged approximately symmetrically with respect to the optical axis at a predetermined distance from the optical axis, and the plurality of samples are arranged slightly with respect to the optical axis direction so that the surfaces facing each other face the detection surface side. A deflector is disposed in the vicinity of the final stage focusing lens, and the electron beam deflected by the deflector in a direction away from the optical axis is directed at a slight angle to the surface. In order to make the electron beam incident on one of the plurality of samples, a deflection means is provided which is either combined with the final stage focusing lens or provided separately, and for switching the sample to be irradiated with the electron beam between the plurality of samples. An electron beam reflection diffraction image observation device equipped with a switching means.