JP2000180318A - Method for preparing sample for analyzing pole surface layer part in electron beam micro-analysis - Google Patents

Abstract

PROBLEM TO BE SOLVED: To implement a sample preparing method which prevents the end parts of a test piece from coming off, improves reliability in the most surface layer part of the test piece, makes the function of setting automatic focus follow by resolving the luminance difference between resin and a metal test piece, and improves qualifying performance in mapping analysis in a sample for performing qualitative and quantitative analysis by a characteristic x-ray signal in electron beam micro-analysis. SOLUTION: A metal test piece 2 is cut out of a sample 1 in a cutting process P1, and a complementary layer formed of a plating layer 3 is formed on the most surface layer of the metal test piece 2 in a plating layer preparing process P2. In this case, the hardness of the plating layer 3 similar to that of the metal test piece 2 is selected for preventing the end parts of the metal test piece 2 from coming off. Next, the metal test piece 2 in which the plating layer 3 is formed is embedded in resin 4 to obtain a metal test piece 2 in a resin embedding and grinding process. In addition, a sample for analyzing pole surface layer parts by providing the plating layer 3 similar in luminance to the metal test piece 2 for the sample formed of two layers of the resin and the test piece extremely different in luminance and resolving the inconvenient condition that the automatic focus setting function of a device body with the function of setting luminance adjustment and automatic focus does not follow between the resin and test piece layers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preparing an analytical sample used for performing quantitative and qualitative analysis of an extremely surface portion of a metal test piece in electron beam microanalysis.

[0002]

2. Description of the Related Art The analysis range of qualitative and quantitative analysis in electron beam microanalysis is ambiguous, and the method of preparing the sample varies depending on the purpose of measurement. When the polishing of the analysis target surface is possible for the analysis purpose in the sample preparation, the sample preparation is generally performed through the process of FIG. Step P1 of cutting the metal base material 1 as a sample into dimensions determined for each device
Thereafter, a step P3 of embedding the cut test piece 2 in the resin 4 and mirror-polishing the analysis target surface is performed, and the surface is coated in some cases.

The characteristic X in electron beam micro-analysis
When performing qualitative and quantitative analysis of a sample using a linear signal, the intensity of the signal changes depending on the degree of polishing and inclination of the measurement surface.In particular, in the analysis of the surface layer, loosening of the end of the test piece due to polishing requires accurate analysis. This is fatal to perform, and requires a procedure such as minimizing loosening by performing polishing in a state of being embedded in a resin. However, between the resin and the test piece layer, several tens
From the standpoint of performing a microanalysis of μm or less, it cannot be said that the two layers are completely two layers, and voids due to shrinkage of the resin and an oxidized layer on the surface layer of the metal test piece are generated. This void layer is several tens
The qualitative and quantitative analysis of the surface layer of the test piece at the μm level is difficult, and a method for preparing a sample that complements this void layer has not yet been proposed. Was to do.

[0004]

The method for preparing an analytical sample proposed in the prior art has a method for preparing a layer that complements the void layer between the resin and the test piece, which is a problem in the analysis of the very surface layer on the order of several tens of micrometers. Nothing was found, and only the sample preparation method, which was quantitatively unreliable, was carried out in the extreme surface layer part due to the change in characteristic X-rays caused by this void layer.

Further, in the sample manufactured by the conventional manufacturing method, since the difference in hardness between the resin and the metal test piece is remarkable, the effect of alleviating the loosening of the end portion during polishing by filling with the resin is completely prevented. It was not possible to do so, which hindered the reliability of the extreme surface layer analysis.

Further, when a sample manufactured by the conventional method is analyzed by an electron beam micro-analysis machine having a brightness adjustment automatic focus setting function, the automatic focus setting function is applied to a brightness difference between a resin and a metal test piece. Without following, the quantification of the mapping analysis was further impaired.

Therefore, a first object of the present invention is to provide a conventional manufacturing method comprising a cutting step P1 of the metal base material 1, a resin embedding and polishing step P3 of the cut metal test piece 2, and a plating method of the metal test piece 2. By providing the step P2, a manufacturing method including cutting, plating, and embedding of the metal test piece 2 is improved, and a method for manufacturing a sample having a layer that complements a void layer between the resin and the test piece is provided. It is. It is desirable to select a plating layer 3 having a hardness close to that of the metal test piece 2 in order to prevent the end portion from loosening.

A second object of the present invention is to provide a method for preparing a sample for analysis of an extreme surface layer, wherein the plating step P2 is a step of preparing a complementary layer comprising a plating layer 3 having a luminance closer to the metal test piece 2. It is to provide.

[0009]

Means for solving the problems of the present invention are as follows.
In the sample preparation process of the sample for electron beam microanalysis prepared in the cutting process P1 of the sample and the polishing process P3 of the resin embedding / analysis target surface, the resin embedding and polishing process P3
3. A method for producing a sample for electron beam microanalysis, wherein a plating step P2 for a metal test piece is provided in a stage prior to the step (c). Here, in order to prevent loosening of the end of the metal test piece 2, it is desirable to select a plating layer 3 having a hardness close to that of the metal test piece 2.

According to a second aspect of the present invention, there is provided a resin test apparatus having significantly different luminances for the purpose of resolving a problem that an automatic focus setting function of a body having a luminance adjustment automatic focus setting function does not follow between resin and test piece layers. This is a method for preparing a sample for extreme surface layer analysis consisting of three layers of a resin-plate-test piece having a plating layer whose luminance is close to that of a metal test piece in a sample of two pieces.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Conventional metal base material 1 cutting process P
1. In contrast to the method for preparing a sample for an electron beam microanalyzer consisting of two layers of a resin-test piece, which comprises a resin embedding / polishing step P3 of the cut test piece 2, the method for preparing a sample for an extreme surface layer analysis of the present invention , Cutting process P1 of metal base material 1
And a plating step P2 for forming plating on the metal sample 2 between the cutting test piece polishing and the resin embedding step P3.
This is a method for preparing an extremely surface layer analysis sample composed of three layers of a resin-plated layer-test piece in which a gap layer between the resin-test piece is complemented by a plating layer 3.

In a plating step P2, a metal test piece before embedding is prepared by a chemical plating method or an electrolytic plating method. In this case, the influence of chemical loss and physical deterioration of the test piece, such as erosion of the test piece, by the chemical plating method or the electrolytic plating method on the analysis accuracy of this analysis method is extremely small.

Here, the thickness of the plating layer 3 depends on the analysis method and the analysis conditions. For example, when mapping the extreme surface layer, mapping information is collected by scanning inside a rectangle that includes the surface layer of the measurement range. Since the plating layer 3 is uniformly applied regardless of the shape of the surface layer portion,
When the surface layer portion of the measurement range has irregularities, the difference in position between the concave portion and the convex portion within the range becomes the minimum thickness of the plating layer 3. In the case where the unevenness of the surface layer is fine, or when it is not necessary to consider the shape of the surface layer such as by line analysis, the thickness of the plating layer 3 is set according to analysis conditions such as the beam diameter.

The metal element formed as the plating layer 3 is selected from elements other than the element to be analyzed and which does not cause physical or chemical deterioration due to correlation with the element to be analyzed.

The plating time is determined by the thickness of the plating layer 3 and the plating method selected.

By providing between the resin and the test piece a step of forming a plating layer 3 having a hardness close to that of the metal test piece 2 in addition to the resin 4 or more, the resin and the test piece have two or more layers. In this way, a sample for analysis of an extremely surface layer portion which can alleviate loosening of the end portion of the metal test piece due to polishing can be produced.

With the introduction of a process P2 in which a complementary layer between the resin and the test piece is formed by plating with a luminance close to that of the metal test piece 2 to the resin 4 or more, the automatic focus setting function of the body having the brightness adjustment automatic focus setting function is realized. In addition, it is possible to produce a sample for analysis of an extreme surface layer portion, which eliminates the problem of not following between the resin and the test piece layer and enables more accurate mapping analysis of the extreme surface layer portion.

[0018]

Example 1 A sample was prepared for investigating the state of surface decarburization by linear analysis. After cutting the test piece to the dimensions specified or less, a Co plating layer was formed by a chemical plating method. The plating solution is 0.05 mol / l cobalt sulfate, 0.2 mol
The pH was adjusted to 10 with NH ₄ OH using a 0.5 mol / l aqueous solution of ammonium sulfate / l / l sodium phosphate. 0.5m after degrease the metal test piece with acetone
The pretreatment is performed by dipping in an ol / l sodium hypophosphite aqueous solution. A test piece is put into a plating solution heated to 90 ° C. to perform plating. After the plating layer was applied, the analysis surface was exposed by cutting after plating, the resin was embedded as before, and the surface was polished to a mirror surface by wet polishing as in the past, to prepare a sample. From the beam diameter size set by the line analysis method, Co
The plating layer thickness was about 10 μm.

In the conventional sample consisting of two layers of the resin and the test piece, the metal test piece did not loosen the end of the metal test piece to a certain extent. A profile indicating a decrease is obtained. For this reason, in the sample to investigate the decrease of the component in the extreme surface layer,
Judgment with conventional samples was highly difficult,
In the three-layer sample composed of resin, plating, and test piece proposed by the present invention, loosening of the extreme surface layer portion is remarkably alleviated by the plating layer having a hardness close to that of the metal test piece, and the extremely reliable extreme surface layer portion is reduced. Analytical results were obtained.

[0020]

Example 2 A sample was prepared for investigating the surface state of carbon steel by mapping. After cutting the test piece to a size less than the specified model, a Ni plating layer was produced by a chemical plating method. The plating solution is 0.1 mol / l sodium citrate,
0.1 mol / l nickel sulfate, 0.1 mol / l aqueous solution of sodium hypophosphite, NaOH or NH ₄ O
Adjust to pH = 9 with H. After the metal test piece is degreased with acetone, a pretreatment is performed by immersing the metal test piece in a 0.5 mol / l aqueous solution of sodium hypophosphite. A water bath is set at 85 ° C., and a test piece is put into a plating solution heated to 80 ° C. to perform plating. After the plating layer is applied, as before, the analysis surface after plating is exposed by cutting, the resin is embedded as before and polished to the mirror surface by wet polishing,
A sample was prepared. The Ni plating layer thickness was about 20 μm from the analysis area of 500 × 300 μm and the roughness of the surface layer.

By forming a complementary layer between the resin and the test piece by plating, not only the slack at the end of the metal test piece was reduced as in Example 1, but also the brightness of the metal test piece was higher than that of the resin. The problem that the automatic focus setting function of the body with the brightness adjustment automatic focus setting function does not follow between the resin and the test piece layer is resolved, and more accurate mapping analysis of the extreme surface layer part becomes possible. Was.

[0022]

As described above, according to the present invention, the slack of the end of the test piece during polishing is remarkably reduced, and the automatic focus setting function of the body having the brightness adjustment automatic focus setting function is provided between the resin and the test piece layer. The problem of not following is eliminated. As a result, in electron beam microanalysis,
It is possible to provide an extremely-surface-layer-analyzing sample capable of performing a qualitative and quantitative analysis of a metal test piece of an extremely-surface layer of 0 μm or less with high accuracy, and the effect is extremely large.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a conventional analysis sample composed of two layers of a resin-test piece.

FIG. 2 is a schematic diagram showing a sample for analysis of an extreme surface layer portion composed of three layers of a resin-plate-test piece of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal base material 2 Metal test piece 3 Plating layer 4 Resin P1 Cutting process P2 Plating layer preparation process P3 Resin embedding and polishing process

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinichi Kitade 3007 one character, Nakajima character in Shima, Himeji-shi, Hyogo F-term in Sanyo Special Steel Co., Ltd. 2G001 AA03 BA05 CA01 GA05 GA06 KA01 RA01 RA02 RA08

Claims (2)

[Claims] 1. A plating step for a metal test piece prior to a resin embedding step in a sample preparation step of an electron beam micro-analysis sample prepared by cutting a metal test piece, embedding a resin, and polishing an analysis target surface. A method for producing a sample for electron beam microanalysis, wherein the method is provided. 2. The method according to claim 1, wherein the plating step is a step of producing a plating layer having a luminance close to that of the metal test piece.
3. The method for producing a sample for electron beam microanalysis according to item 1.