JPS636437A - Pyramidal indenter for electron microscope - Google Patents

Abstract

PURPOSE:To increase the angle of the bevel of a identation and to improve the contrast of an image, and to accurately measure the size of the indentation by setting the angle of the slanting surface forming the pyramid of a pyramidal indenter for an electron microscope to the center line to 35-55 deg.. CONSTITUTION:The pyramidal indenter 10 is in a rectangular pyramidal shape, the angle of the bevel 11 to the center line 12 is 45 deg., and an indentation having a 90 deg. spread angle is formed in a material. When this indentation is irradiated with an electron beam (e) from the scanning electron microscope, a reflected electron beam 17 is generated on the bevel 15 of the indentation 13 almost horizontally toward the opposite slanting surface 16 in addition to a secondary electron beam 14 and detected by the secondary electron beam detector of the scanning electron microscope. Consequently, the generation quantity of the secondary electron increases, so the contrast is improved and the contour part 19 of the indentation 13 appears clearly, so that the size of the indentation 13 is accurately measured.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a pyramidal indenter, and in particular to a pyramidal indenter for electron microscopy, which is pressed against the surface of a material with a predetermined pressing force in order to observe the indentation using an electron microscope and learn the characteristics of the material. Regarding indenters.

[Conventional technology]

Conventionally, a Vickers hardness tester has been used as a hardness tester for measuring the hardness of materials. As shown in Figures 5 and 7, this is done by applying a square pyramid indenter 1 made of diamond and having opposing slopes forming an angle of 136 degrees to the material 2, and applying a predetermined constant load F. Removal, 6th
As shown in the figure, a square pyramid-shaped indentation 3 remains on the surface of the material.
The diagonal dimension d of the material 2 is measured and converted into the hardness of the material 2.

(Problems to be solved by the invention) By the way, with the recent advances in semiconductor, thin film, etc. technology,
In order to evaluate its mechanical strength, a hardness test may be conducted in a minute area (for example, an area of about 50 nm in the depth direction and 10 gm or less in the 11@ direction). For this reason, the hardness test similar to the one described above is performed.In this case, the load of pressing the pyramidal indenter against the material is minute, and the traces left in minute areas are small, and the dimensions of the material cannot be measured using an optical microscope. We use a scanning electron microscope to make observations. However, there is a problem in that it is not possible to accurately observe and measure the indentations made with the square pyramid indenter for the Viracas hardness test described above using a scanning electron microscope.

That is, even if the measurement was carried out at a high magnification of 11111, the contour Vj6 (indicated by a broken line in FIG. 9) of the indentation of the quadrangular pyramid indenter could not be observed, as shown in FIG. 9, but only near the ridge line 7 of the indentation. Image 7 will appear, making it impossible to accurately measure dimensions in the diagonal direction.

As shown in Fig. 8, the slope 4 of the indentation 3 formed on the material is 68 degrees to the electron beam e irradiated by the electron microscope, which is close to horizontal, so it is horizontal (90" to the electron beam). - This is because the contrast with the film surface portion 5 is difficult to form.

Therefore, even if the material is tilted to increase contrast, the contrast will improve in some areas, but the contrast will decrease in other areas, which is not practical.

(Means for solving the problems) The technical means of the present invention for solving the above technical problems are as follows:
As described above, in the pyramid indenter for electron microscopes, the angle of the inclined surface forming the pyramid with respect to the center line is set to 35 degrees to 55 degrees.

(Example) Examples of the pyramidal indenter for electron microscopes according to the present invention will be described below based on the drawings.

1 to 3 show examples of the pyramid indenter for electron microscopes according to the present invention. In this embodiment, the pyramidal indenter lO has a quadrangular pyramidal shape with a slope 11
The angle it makes with the center line 12 is 45 degrees, that is, the opposite slope 1
The angle formed by 1 is 90 degrees. Therefore, an indentation with an opening angle of 90 degrees is formed in the material, as shown in FIG.

When this indentation is irradiated with an electron beam e from a scanning electron microscope,
As shown in FIG. 3, from the slope 15 of the indentation 13 formed in the material 2, in addition to the secondary electron beam 14, a reflected electron beam 17 is emitted approximately in the horizontal direction toward the opposing slope 16. Ki occurs with the distribution shown by the solid line. And this reflected electron &1
17, the secondary electron beam 1 is also emitted from the opposing slope 16.
8 is generated and the secondary electron beam 18 emitted from the opposing slope 16 is also detected by the secondary electron beam detector of the scanning electron microscope in the same way as the secondary electron beam 14 from the slope 15 irradiated with the electron beam e. (not shown). Therefore, when the pyramidal indenter according to this embodiment is used, the angle of the slope of the indentation becomes larger than that of the conventional one, so that the amount of secondary electrons generated on this slope is larger than that of a general horizontal part, and the relative Since the secondary electron beam 18 from the facing slope 16 is applied, the contrast is also directed, the outline 19 of the indentation 13 is clearly visible, and the dimensions of the indentation 13 can be measured accurately.

It also improves the contrast of the image of the indentation, making it easier to find where the indentation is in the material, and making it easier to position the pyramid indenter for a new test on an adjacent area. What can you do? Furthermore, as shown in FIG. 4, by examining the cracks 20 at the corners of the indentations 13, for example, the ceramic material brittleness test KIC (
Evaluation methods such as K-Wan-C and scratch tests can also be easily observed.

In the above example, the angle of the inclined surface of the pyramidal indenter with respect to the center line was set at 45 degrees, but even if this angle is too small to improve the contrast, the diagonal length and hardness in the hardness test When testing a l;l film, the influence of the base on which the thin film is formed may occur, and if it is too large, it may be impossible to improve the contrast, or the angle of 35 degrees or If it is in the range of 55 degrees, it will have the same effect as in the case of 45 degrees in the above example.
This has been confirmed through experiments by the inventor of the present invention.

Further, in the above embodiments, the shape of the indenter is a square pyramid, but it goes without saying that the shape of the indenter may be another pyramid shape such as triangular silver.

(Effects of the Invention) According to the present invention, since the angle of the inclined surface forming the pyramid of the electron microscope indenter with respect to the center line is set to 35 degrees to 55 degrees, the angle of the inclined surface of the indentation becomes large, and the contrast of the image increases. This has the effect that the contour of the indentation is clearly displayed, the dimensions of the indentation can be accurately measured, and the hardness test can be carried out accurately.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a pyramidal indenter for an electron microscope according to the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. Figure 4 is a plan view showing an electron microscope image of an indentation from a brittleness test, Figure 5 is a side view showing an indenter of a Vickers hardness tester, and Figure 6 is a plan view showing an indentation from a conventional Vickers hardness test. , Fig. 7 is a perspective view showing a conventional pyramid indenter for Vickers hardness testing, Fig. 8 is: Jr, W-VI & 911EIr in Fig. 5, side view;
FIG. 9 is a plan view showing an image of the indentation shown in FIG. 6 with an electron microscope. 10 - Pyramid indenter 11... Inclined surface 12... Center line Patent applicant Akashi Seisakusho Co., Ltd. Representative Patent attorney Hajime Tsuchibashi Figure 1 Figure 2 Figure 1 ° 3rd vA

Claims (1)

[Claims] In a pyramidal indenter for electron microscopes that is pressed against the surface of a material with a predetermined pressing force in order to observe the indentations with an electron microscope and learn the characteristics of the material, the angle of the inclined surface forming the pyramid with respect to the center line is set between 35 degrees and 55 degrees. A pyramidal indenter for electron microscopes featuring: