JP6515320B2 - Sample holder and observation method by transmission electron microscope - Google Patents

Description

  The present invention relates to, for example, a sample holder for a transmission electron microscope and a transmission electron microscope suitable for producing a high quality transmission electron microscope (TEM) sample necessary for measuring the amount of grain boundary segregation boron in steel etc. It relates to the observation method.

  In the grain boundaries of steel, the added alloying elements and the impurity elements mixed in at the time of production are often more concentrated than the base material. Such an element enrichment phenomenon is called grain boundary segregation. Grain boundary segregation greatly affects the properties of the steel. For example, it is known that boron is concentrated and present at austenite grain boundaries of the steel, and the grain boundary segregation of the boron significantly improves the hardenability of the steel. ing. Therefore, controlling the amount of grain boundary segregation is essential for producing high-performance steel materials, and controlling the amount of grain boundary segregation of boron is particularly important.

  However, it is very difficult to accurately measure the grain boundary segregation amount of boron at austenite grain boundaries in steel, and a special analysis technique is required. Specifically, in grain boundary segregation, since elements are concentrated in a region of 1 nm or less in width, it is necessary to use a measurement method having a spatial resolution of 1 nm or less for analysis thereof. There are atom probe method and transmission electron microscopy as such high spatial resolution measurement method. Among them, in the atom probe method, the size of the measurement area is about 100 nm, and it is difficult to locate the austenite grain boundary to be measured in the measurement area, so the measurement efficiency is poor.

  On the other hand, when grain boundary segregation is measured by transmission electron microscopy, an electron beam is irradiated to a minute area near the grain boundary, and the element concentration is measured using fluorescent X-rays emitted from that area. Distributed X-ray spectrometry (EDS) is widely used. Here, in the EDS method, in order to prevent deterioration of the spatial resolution, it is effective to make the thickness of the sample used for measurement extremely thin (see, for example, Non-Patent Document 1). However, in the EDS method, when the sample is thin, the amount of X-ray signal becomes weak, which may make measurement difficult. Therefore, instead of the EDS method, electron beam energy loss spectroscopy (EELS method) is preferably used in which a sufficient amount of signal can be obtained even if the sample is thin.

  In grain boundary segregation measurement of steel by the EELS method, in order to obtain sufficient spatial resolution, it is desirable to make the sample thickness 20 nm or less. A focused ion beam (FIB) processing apparatus is used to produce such an extremely thin sample. When producing a TEM sample by FIB, it is efficient to make the incident direction of the ion beam orthogonal to the incident direction of the electron beam of the TEM. In response to such a demand, a sample holder that can be shared by an FIB processing apparatus and a TEM, in which a notch is provided on the side to which the ion beam of FIB is incident, has been proposed (see, for example, Patent Document 1) .

  The surface of the sample produced by FIB is activated by ion beam irradiation, and an oxide film is formed on the surface when it is left in the air. The thickness of the native oxide film on the sample surface is about 5 nm, and when the surfaces on both sides are oxidized, the total thickness of the oxide film is about 10 nm. If the sample thickness is 20 nm, the oxide film layer reaches half or more of the base material, and it becomes difficult to accurately measure the grain boundary segregation amount.

  Therefore, in order to measure grain boundary segregation in steel with high precision using transmission electron microscopy, a sample with a sample thickness of 20 nm or less is prepared, and the sample is transmitted without being exposed to the atmosphere. It is desirable to insert it into an electron microscope and measure it using the EELS method. In order to meet such requirements, a configuration has been proposed in which a mechanism for blocking the vicinity of the sample from the atmosphere is provided to the sample holder that can be shared by a focused ion beam processing apparatus (FIB processing apparatus) and a transmission electron microscope (TEM). (See, for example, Patent Document 2). According to this configuration, when the sample holder is transferred to the TEM after sample preparation by the FIB processing apparatus, the sample support portion supporting the sample is stored in the cylinder, and the atmosphere in the vicinity of the sample is not It can be held in an active atmosphere or vacuum.

JP, 2010-146957, A JP 2005-327710 A

G. Shigesato et al., Materials Science & Engineering A, Volume 556, 2012, pp 358-365

  However, the sample holder for TEM described in Patent Documents 1 and 2 can irradiate an ion beam at the time of sample preparation from a direction perpendicular to the irradiation direction of the electron beam at the time of observing the sample with a transmission electron microscope. Most of the portion in the vicinity of the sample of the cylindrical outer shell of the sample holder is cut off. In such a structure, since the rigidity of the tip of the sample holder is low, sample drift during observation and measurement is large, and it is considered that it is not suitable for high resolution observation and measurement. Therefore, the sample holder described in Patent Documents 1 and 2 is not always suitable for measuring grain boundary segregation of steel.

  The present invention has been made in view of the above-mentioned circumstances, and the object of the present invention can be commonly used in preparation of a sample by FIB and observation by TEM, has sufficient rigidity, and can oxidize a sample. It is an object of the present invention to provide a sample holder for a transmission electron microscope and an observation method by a transmission electron microscope that can suppress the

In order to solve the above problems, according to one aspect of the present invention, it is a sample holder that can be shared by a transmission electron microscope and a focused ion beam processing apparatus, wherein the cylindrical outer shells of the sample holder face each other. Space formed between the first and second openings which are respectively formed in a partial region where the electron beam or the ion beam is incident from one of the first and second openings in the outer shell And the sample support portion configured to be able to rotate the sample with the axial direction of the sample holder as the rotation axis direction, and to block the space from the outside air when the electron beam and the ion beam are not irradiated. An atmosphere blocking member for closing the first and second openings, wherein the outer periphery of the first and second openings is surrounded by the outer shell, and the sample support is a sample Stand and sample stand support The sample table support is provided on the side of the space far from the tip of the sample holder, and the sample table is installed on the sample table support so as to extend in the axial direction of the sample holder. is, the sample stage support part, the axial direction of the sample holder Ru is rotatably configured as a rotation axis direction, and wherein the sample holder is provided.
In the outer shell, there may not be an open portion connecting the first opening and the second opening along the circumferential direction of the sample holder.
Further, the sample stage support may be rotatable independently of the outer shell.
Further, a notch may not be present in a portion of the outer shell, which is present between the first opening and the second opening along the circumferential direction of the sample holder.

  In the sample holder, the sample may be rotated by 90 degrees by the sample support portion at the time of ion beam irradiation and at the time of electron beam irradiation.

  In the sample holder, the atmosphere blocking member is a cylindrical member provided so as to cover the outer periphery of the outer shell and movable in the axial direction of the sample holder, and the sample of the outer shell A seal member externally fitted to the outer shell is provided at a position sandwiching the first and second openings in the axial direction of the holder, and the atmosphere blocking member is provided with the first and second openings. At the time of covering, the space may be shut off from the open air by the close contact between the inner wall surface of the atmosphere blocking member and the seal member.

Further, in order to solve the above problems, according to another aspect of the present invention, there is provided a transmission electron microscope observation method using a sample holder that can be shared by a transmission electron microscope and a focused ion beam processing apparatus. The sample holder is formed in partial regions of the cylindrical outer shell of the sample holder facing each other, and the first and second openings through which the electron beam or the ion beam is incident from one of the first and second openings. A sample support portion provided in a space corresponding to the first and second openings in the outer shell and configured to be able to rotate the sample with the axial direction of the sample holder as the rotation axis direction; the electron beam and An atmosphere blocking member for closing the first and second openings so as to block the space from the open air when the ion beam is not irradiated, and the periphery of the outer shape of the first and second openings Is The sample support portion is surrounded by a shell, and the sample support portion includes a sample table and a sample table support portion, and the sample table support portion is provided on the side of the space far from the tip of the sample holder. the sample stage support part, said sample stage so as to extend in the axial direction of the sample holder is installed, the sample stage support part has an axial direction of the sample holder is rotatably configured as a rotation axis direction And rotating the sample support unit so that the film surface of the sample is perpendicular to the direction of incidence of the electron beam, and the process from the first opening or the second opening is performed. There is provided a method of observation by a transmission electron microscope , comprising irradiating a sample with the electron beam and observing a transmission electron microscope image .

  According to the present invention, a sample holder for transmission electron microscopy, which can be shared between the preparation of a sample by FIB and the observation by TEM, has sufficient rigidity and can suppress oxidation of the sample, and a transmission for a transmission electron microscope It becomes possible to provide an observation method with a type electron microscope. Further, according to the present invention, industrial contribution is extremely remarkable, for example, a high quality TEM sample necessary for measurement of grain boundary segregation boron in steel etc. can be produced.

It is a figure which shows an example of the aspect of the sample holder which concerns on this embodiment at the time of FIB processing. It is a figure which shows an example of the aspect of the sample holder which concerns on this embodiment in the state which interrupted | blocked the atmosphere of the sample vicinity. It is a figure which shows an example of the aspect of the sample holder which concerns on this embodiment at the time of TEM observation. It is an example of the TEM image of the former austenite grain boundary in the sample produced with the sample holder concerning this embodiment. (A) The figure which shows an example of the EELS spectrum acquired from the sample produced with the sample holder which concerns on this embodiment, and the figure which shows an example of the EELS spectrum acquired from the sample produced by (b) conventional sample production methods . (A) A diagram showing an example of the boron concentration distribution in the vicinity of the prior austenite grain boundary measured by the sample manufactured by the sample holder according to the present embodiment, and (b) Old austenite measured by the sample manufactured by the conventional sample manufacturing method It is a figure which shows an example of boron concentration distribution of the grain boundary vicinity. It is a figure which shows the structure of a sample holder in which a sample stand support part does not rotate. It is a figure which shows the structure of the conventional sample holder in which the sample stand support part did not rotate but the open part was provided.

  The present invention will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. In the present specification and the drawings, components having substantially the same functional configuration will be assigned the same reference numerals and redundant description will be omitted.

  1 to 3 are schematic views showing one configuration example of a sample holder 100 according to an embodiment of the present invention. In these figures, the left side in the figure is the tip (tip side) of the sample holder 100, and the right side in the figure (hereinafter also referred to as the base side of the sample holder 100) is the outside of the FIB processing apparatus or TEM, ie, in the atmosphere. It is a part located in 1 to 3 mainly show the configuration of the tip end side and the root side of the sample holder 100, and the configuration between them is not shown.

  In addition, in the following description, when it only describes as the apparatus exterior, it shall mean the exterior of a FIB processing apparatus or TEM unless there is particular mention. Similarly, when simply described as inside of the device, it means inside of FIB processing device or TEM unless otherwise stated.

  As shown, the sample holder 100 has a substantially cylindrical outer shell 9, and an O-ring 4 is externally fitted to the root side of the outer shell 9. When the sample holder 100 is inserted into the ion beam processing apparatus or TEM, the O-ring 4 blocks the portion of the sample holder 100 located inside the apparatus from the outside of the apparatus with good airtightness.

  FIG. 1 shows a state in which the sample holder 100 is inserted into the FIB processing apparatus and irradiation of a focused ion beam is possible. As shown in FIG. 1, the outer shell 9 of the sample holder 100 has openings 10 and 11 (hereinafter both the first opening 10 and the second opening 11) in partial regions facing each other. Is called). The openings 10 and 11 are openings having no open part, the four directions of which (the vertical direction and the horizontal direction in the figure) are surrounded by the members of the sample holder 100. In the following, the axially extending member constituting the openings 10 and 11 is also referred to as a sample holder side wall member 8.

  In the present embodiment, the sample 2 is fixed in the space 12 sandwiched by the openings 10 and 11 in the outer shell 9, and an ion beam is incident from either one of the openings 10 and 11 toward the sample 2. The sample holder 100 is inserted into the FIB device as follows. For example, when the opening 10 is on the incident side of the ion beam, the opening 11 is on the exit side of the ion beam. Thereby, the ion beam which has passed through the vicinity of the sample 2 passes through the openings 10 and 11 without being irradiated to the members of the sample holder 100, so that the members of the sample holder 100 are sputtered by sputtering. It can prevent pollution.

  The sample holder 100 is provided with a cylindrical atmosphere blocking member 6 so as to cover the outer periphery of the outer shell 9. The atmosphere blocking member 6 is configured to be movable in the axial direction of the outer shell 9 so as to expose or cover the openings 10 and 11 (i.e., the space 12). In FIG. 1, the atmosphere blocking member 6 is located on the base side of the sample holder 100 relative to the openings 10 and 11, and the openings 10 and 11 are exposed.

  The sample stand support 5 is provided on the side of the openings 10 and 11 far from the tip of the sample holder 100, and the sample stand 3 extends in the axial direction of the sample holder 100. Will be installed. The sample 2 is fixed to the sample stand 3. Hereinafter, the sample stage 3 and the sample stage support 5 will be collectively referred to as a sample support. The sample stand support 5 is configured to be rotatable with the axial direction of the sample holder as the rotation axis direction, and the rotation angle can be adjusted by the sample stand rotation knob 7 provided on the root side of the sample holder 100 . When the sample holder 100 is inserted into the FIB processing apparatus, the angle of the sample support 5 is set so that the direction parallel to the film surface of the sample 2 coincides with the ion beam incident direction by the sample stand rotation knob 7 Adjusted. Thus, the sample support portion is configured to be able to rotate the sample with the axial direction of the sample holder 100 as the rotation axis direction.

  The sample 2 is formed of Mo, Cu or the like in a state of being processed into a size of several tens μm in width, several tens of μm in length and about 100 nm in thickness by electrolytic polishing, ion milling, FIB or the like in advance. It is fixed to stand 3. The sample table 3 has, for example, a semicircular shape having a diameter of about 3 mm and a thickness of about 10 to 50 μm. As the sample stand 3, what is generally marketed which has such a shape can be used conveniently. Fixation of the sample 2 on the sample table 3 is performed by a local vapor deposition method using tungsten, gold or the like.

  The thin film sample 2 having a thickness of about 100 nm before processing is disposed so that the film surface is substantially parallel to the ion beam incident direction, and ion beam processing is performed in this state. For ion beam processing, for example, an Ar ion beam at an acceleration voltage of 100 to 1000 V is used. By making the ion beam incident direction substantially parallel to the film surface and setting the acceleration voltage of the ion beam to 1000 V or less, damage to the sample 2 by ion beam processing can be extremely reduced.

  In the case of producing a high quality sample for TEM necessary for measurement of grain boundary segregation boron in steel etc., the thickness of the sample 2 is made about 20 nm or less by FIB processing. Moreover, the damage layer of the surface layer of the sample 2 can be extremely reduced by using an ion beam substantially parallel to the film surface of the sample 2 at an accelerating voltage of 300 V or less for FIB processing in the final finishing stage.

  When the FIB processing is completed, the atmosphere blocking member 6 is slid in the tip direction of the sample holder 100 in the FIB processing apparatus, the openings 10 and 11 are covered with the atmosphere blocking member 6, and the opening in the axial direction of the sample holder 100 The vicinity of the sample 2 is shielded from the external atmosphere by the seal member 1 provided so as to sandwich 10 and 11.

  A state in which the openings 10 and 11 are covered by the atmosphere blocking member 6 and the vicinity of the sample 2 is blocked from the external atmosphere is shown in FIG. The sealing member 1 is, for example, an O-ring externally fitted to the outer shell 9, and the atmosphere blocking member 6 is in close contact with the sealing member 1 when the atmosphere blocking member 6 covers the openings 10 and 11. To be precisely controlled. Thereby, the atmosphere in the vicinity of the sample 2 can be maintained in a high vacuum state. If necessary, the atmosphere in the FIB processing apparatus may be an inert gas atmosphere such as Ar gas, and the atmosphere blocking member 6 may be attached in this state.

  Next, the sample holder 100 is removed from the FIB processing apparatus and inserted into a transmission electron microscope (TEM) in a state where the vicinity of the sample 2 is shielded from the external atmosphere. A state in which the atmosphere blocking member 6 is slid to the base side of the sample holder 100 after the insertion into the TEM is shown in FIG. As shown in FIG. 3, when the sample holder 100 is inserted into the TEM, the sample stand rotation knob 7 is rotated to turn the sample stand supporting portion 5 90 degrees from the time of ion beam irradiation, and the film of the sample 2 The angle of the sample support 5 is adjusted so that the surface is substantially perpendicular to the incident direction of the electron beam. In this state, an electron beam is irradiated to the sample 2 from any one of the openings 10 and 11, and observation of a transmission electron microscope image and EELS analysis are performed.

  Thus, in the present embodiment, after the sample preparation by FIB, observation and measurement by TEM can be performed without exposing the sample 2 to the air. As a result, almost no oxide film layer is formed on the surface of the sample 2, and it becomes possible to measure the grain boundary segregation amount in the steel with higher accuracy.

  Furthermore, in the sample holder 100 according to the present embodiment, the sample holder side wall members 8 exist on both sides of the sample 2 in the space 12 in which the sample 2 is fixed. Therefore, the rigidity of the tip of the sample holder 100 is relatively high. Therefore, at the time of TEM image observation at high magnification and at the time of EELS measurement, the sample 2 can be stably stopped, and observation and measurement at higher spatial resolution become possible.

  Here, for example, as shown in FIG. 7, a sample holder 200 having a configuration in which the rotation mechanism of the sample stand support 5 is omitted with respect to the sample holder 100 according to the present embodiment will be considered. In the sample holder 200, since the sample stand support 5 can not be rotated, as shown in FIG. 7, the incident direction of the electron beam in the TEM and the incident direction of the ion beam in FIB processing on the sample 2 are made to coincide with each other. I have no choice. Therefore, for example, if the direction of the sample 2 is set to correspond to the observation by the TEM, as shown in the figure, the ion beam is perpendicularly incident on the film surface of the sample 2 and damage to the sample 2 occurs. It will be huge.

  On the other hand, in the present embodiment, by providing the rotation mechanism of the sample stand support 5 in the sample holder 100, the angle of the sample 2 is appropriately changed between FIB processing and TEM observation. As described above, for example, at the time of FIB processing, the sample 2 is disposed such that the film surface of the sample 2 is substantially parallel to the incident direction of the ion beam. Further, for example, at the time of TEM observation, the sample 2 is disposed such that the film surface of the sample 2 is substantially perpendicular to the incident direction of the electron beam. Therefore, in the present embodiment, as described above, it is possible to prevent the situation where the sample 2 is subjected to a great deal of damage at the time of the FIB processing.

  Further, one configuration example of a conventional sample holder 300 is shown in FIG. In the conventional sample holder 300, as shown in FIG. 8, the rotation mechanism of the sample table support 5 is omitted with respect to the sample holder 100 according to the present embodiment, and the electron beam and ion beam In order to make the light incident from different directions, a part of the outer shell 9 is cut away in the circumferential direction, and an open part 33 is provided. The open portion 33 corresponds to a structure formed by removing one of the sample holder side wall members 8 in the openings 10 and 11 of the sample holder 100 according to the present embodiment, and it is a so-called open opening. It can be said that there is.

  In the sample holder 300, as shown in the figure, the ion beam can be made incident on the sample 2 from a direction substantially perpendicular to the incident direction of the electron beam, ie, a direction substantially parallel to the film surface of the sample 2. However, in the configuration, the ion beam that has passed through the vicinity of the sample 2 is irradiated to the member of the sample holder 300 (the sample holder side wall member 8 in the figure), and the member is sputtered. Contamination of sample 2 is inevitable because the sputtered material adheres to sample 2.

  On the other hand, as described above, in the sample holder 100 according to the present embodiment, the openings 10 and 11 are provided at mutually opposing positions of the outer shell 9. Further, in the sample holder 100, the rotation mechanism of the sample support 5 is provided to make the incident directions of the electron beam and the ion beam on the sample 2 different from each other, and for the electron beam and the ion beam to the sample holder 100 The incident directions can be the same (i.e., passing through the openings 10, 11). Therefore, since the ion beam which has passed through the vicinity of the sample 2 passes through the openings 10 and 11 without being irradiated to the members of the sample holder 100, the sample 2 by sputtering the members of the sample holder 100 by the ion beam Pollution can be avoided.

  The following examples further illustrate the feasibility and effects of the present invention.

  The steel sheet of the composition shown in the following Table 1 is heated to 1100 ° C. to 1200 ° C., hot rolled at a temperature of 950 ° C., and an average cooling rate of 30 ° C./sec between hot rolling completion to 650 ° C. And a 20 mm thick hot-rolled sheet.

  From the hot-rolled steel plate manufactured in this manner, a 10 mm square sample piece with a thickness of 1 mm was cut out, and the sample piece was mirror-polished and then inserted into an FIB processing apparatus. Using FIB, an area of 10 μm in length, 3 μm in width and 10 μm in height including prior austenite grain boundaries was cut out from the sample piece, and the cut out sample was fixed to a semicircular Mo grid of 3 mm in diameter. Thereafter, the sample fixed on the Mo grid was processed into a thin film by FIB. The size of the finished thin film sample was 10 μm in length, 0.1 μm in width, and 10 μm in height.

  The thin film sample thus produced was mounted on the sample holder 100 according to the above-described embodiment together with the Mo grid, and inserted into an Ar ion beam processing apparatus. The Mo grid corresponds to the sample stand 3 shown in FIG. 1, and the thin film sample corresponds to the sample 2 shown in FIG. The arrangement of the thin film sample was changed to the state shown in FIG. 1 using the sample table rotation knob 7, and an Ar ion beam was incident on the thin film sample substantially parallel to the film surface. Specific acceleration voltages of Ar ion beams and beam incident angles with respect to the film surface of the thin film sample at that time are shown in Table 2 below. First, an ion beam with an acceleration voltage of 1000 V was irradiated at an incident angle of 10 degrees, and then the ion beam was irradiated while gradually reducing the acceleration voltage and the incident angle. The ion beam irradiation time was about 1 to 10 minutes for each irradiation at each acceleration voltage.

  After Ar ion beam irradiation, the openings 10 and 11 of the sample holder 100 were covered with the atmosphere blocking member 6 in an Ar ion beam processing apparatus. The inner wall surface of the atmosphere blocking member 6 is in close contact with the sealing member 1 so that the vicinity of the sample can be kept substantially vacuum. In this state, the sample holder 100 was removed from the Ar ion beam processing apparatus and immediately inserted into the TEM.

  In the TEM, the atmosphere blocking member covering the openings 10 and 11 (that is, the vicinity of the sample) is retracted to the base side of the sample holder 100 so that the sample can be irradiated with the electron beam (see FIG. 3) ). The sample table rotation knob 7 was rotated to rotate the sample table support 5 by 90 degrees from the time of ion beam irradiation, and the sample was arranged such that the film surface of the sample was approximately perpendicular to the electron beam incident direction. Thereafter, the TEM image was observed to confirm the position of the prior austenite grain boundary, and the portion was observed in an enlarged manner. The observation magnification is about 5 million times. The TEM image taken is shown in FIG.

  Then, the presence or absence of the oxide film layer on the sample surface was examined. The EELS spectrum acquired in the vicinity of the former austenite grain boundary of the sample produced using sample holder 100 concerning this embodiment is shown in Drawing 5 (a). For comparison, a sample manufactured using a conventional sample manufacturing method from a steel material having the same composition as that shown in Table 1 above, ie, after Ar ion beam processing, is transferred to TEM without using the atmosphere blocking member 6 The EELS spectrum near the prior austenite grain boundary obtained as a result of measuring the separated samples is shown in FIG. 5 (b). As shown in FIG. 5B, in the spectrum of the sample produced by the conventional sample production method, the O-K end peak clearly appears, and it can be seen that an oxide film is present on the surface of the sample. On the other hand, as shown in FIG. 5A, the O-K end peak appears in the EELS spectrum acquired without being exposed to the atmosphere after Ar ion beam processing using the sample holder 100 according to the present embodiment. It can be seen that almost no oxide film is present on the sample surface.

  Next, the boron concentration near the prior austenite grain boundaries was measured. Near the former austenite grain boundaries, an electron beam was focused to about 0.1 nm and irradiated on the sample to obtain an EELS spectrum. In the acquired EELS spectrum, measure the integrated intensity of the signals at the B-K end and the Fe-L end, and calculate the ratio of the signal intensity at the B-K end to the signal intensity at the Fe-L end to obtain an electron beam. It was B concentration in steel in the irradiated area. The irradiation position of the electron beam was moved at intervals of 0.2 nm, the B concentration at each point was measured, and the B concentration distribution was obtained.

  A B concentration distribution measured on a sample manufactured using the sample holder 100 according to this embodiment, that is, a sample transferred to a TEM without being exposed to the atmosphere after Ar ion beam processing is shown in FIG. As a comparison, it is a sample manufactured using a conventional sample manufacturing method from a steel material having the same composition as the composition shown in the above Table 1, that is, a sample transferred to TEM without using the atmosphere blocking member 6 after Ar ion beam processing. The measured B concentration distribution is shown in FIG. 6 (b). Referring to FIG. 6A, in the sample manufactured using the sample holder 100 according to the present embodiment, it can be clearly seen that the boron concentration is high at the prior austenite grain boundary. On the other hand, referring to FIG. 6 (b), in the sample manufactured using the conventional sample manufacturing method, the concentration of boron on the prior austenite grain boundary was not clearly detected. It is considered that this is because in the sample manufactured using the conventional sample manufacturing method, the detection of the boron concentration could not be accurately performed because of the oxide film formed on the surface of the sample.

  The above results are shown in Table 3 below. As shown in Table 3 below, by using the sample holder 100 according to the present embodiment, it is possible to prepare a sample in which surface oxidation hardly occurs, and the boron concentration in the vicinity of the prior austenite grain boundary is made more accurate. It has been confirmed that it can be detected.

  For comparison, a sample prepared using a sample holder having a function of blocking the atmosphere in the vicinity of the sample from the open air as in the present embodiment but having a configuration different from that of the sample holder 100 according to the present embodiment The same measurement as in Example 1 was performed. Specifically, as a sample holder to be compared, a sample holder 200 shown in FIG. 7 (one in which the rotation mechanism of the sample stand support 5 is omitted with respect to the sample holder 100 according to the present embodiment), and FIG. The conventional sample holder 300 shown (with the rotation mechanism of the sample support 5 being omitted from the sample holder 100 according to the present embodiment and the openings 10 and 11 being changed to the open part 33) was used. The same steel as in Example 1 was used.

  When the conventional sample holder 300 shown in FIG. 8 was used, although an oxide film on the sample surface was not detected, a sample drift of about 10 nm / minute occurred during measurement of the EELS spectrum. Also, boron enrichment on the prior austenite grain boundaries was not detected. This is considered to be due to the fact that the spatial resolution of the measurement is insufficient because the sample drift during the measurement is large. In addition, it was confirmed that the surface of the sample was contaminated, which may be caused by the irradiation of the sample holder side wall member 8 with the ion beam during the FIB processing. As a result of analyzing the said stain | pollution | contamination, it has confirmed that Cu which seems to appear by having scraped the member of the sample holder 300 has adhered to the sample surface.

  On the other hand, in the sample holder 100 according to the present embodiment, the sample drift can be suppressed to a smaller value as compared with the sample holder 300 shown in FIG. 8 and, as shown in Table 3 above, on the prior austenite grain boundary The boron concentration could be detected with high accuracy. This is because in the sample holder 100, the presence of the sample holder side wall members 8 on both sides of the space 12 in which the sample 2 is fixed maintains a higher value as the rigidity of the tip of the sample holder 100. Conceivable. Moreover, when the sample holder 100 was used, as in the case of using the sample holder 300, the stain on the sample surface was hardly observed. This is because, in the sample holder 100, the ion beam is irradiated in the direction of passing through the openings 10 and 11 facing each other, so that the ion beam passing through the vicinity of the sample 2 is irradiated to the sample holder sidewall member 8 It is considered that there is almost no contamination due to sputtering as described above.

  On the other hand, when the sample holder 200 shown in FIG. 7 is used, although the oxide film on the sample surface is not detected, the Ar ion beam is irradiated perpendicularly to the sample film surface at the time of FIB processing. As compared with the case of using the sample holder 100, the unevenness of the sample surface was larger. Also, boron concentration near the prior austenite grain boundaries could not be detected. This is because the boron concentration measurement by the EELS spectrum is greatly affected by the sample thickness, so in the sample having a relatively large surface unevenness, detection of the boron concentration is carried out using the sample holder 200 shown in FIG. It is thought that it was because it could not be done with high precision.

  On the other hand, in the sample holder 100 according to the present embodiment, the sample support portion 5 holding the sample 2 is configured to be rotatable in the axial direction, and the film surface of the sample 2 in the ion beam irradiation direction is the ion beam irradiation direction. Since the angle of the sample 2 can be adjusted so as to be substantially parallel to that of the sample holder 200, asperities on the sample surface can be suppressed smaller than in the sample holder 200 shown in FIG. As a result, as shown in Table 3 above, the sample holder 100 can detect boron concentration on the prior austenite grain boundaries with high accuracy.

  The above results are shown in Table 4 below. Table 4 below also shows the results in the case of using the sample holder 100 according to the present embodiment described in the first embodiment. As shown in Table 4 below, when using the conventional sample holders 200 and 300 having the function of blocking the atmosphere in the vicinity of the sample from the outside air illustrated in FIGS. 7 and 8, almost no surface oxidation occurs It has been confirmed that although it is possible to prepare a sample, it is difficult to detect boron concentration near the prior austenite grain boundaries.

  Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is obvious that those skilled in the art to which the present invention belongs can conceive of various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also fall within the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 seal member 2 sample 3 sample stand 4 O ring 5 sample stand support part 6 atmosphere blocking member 7 sample stand rotation knob 8 sample holder side wall member 9 outer shell 10, 11 opening 12 space 33 open part

Claims (7)

A sample holder that can be shared by a transmission electron microscope and a focused ion beam processing apparatus,
First and second openings which are respectively formed in mutually opposing partial regions of the cylindrical outer shell of the sample holder and from which either an electron beam or an ion beam is incident;
A sample support portion provided in a space between the first and second openings in the outer shell, the sample support portion being rotatable with the axial direction of the sample holder as the rotation axis direction;
An atmosphere blocking member that blocks the first and second openings so as to block the space from the outside air when the electron beam and the ion beam are not irradiated;
Equipped with
The outer periphery of the first and second openings is surrounded by the outer shell,
The sample support comprises a sample table and a sample table support.
The sample table support is provided on the side of the space far from the tip of the sample holder, and the sample table is installed on the sample table support so as to extend in the axial direction of the sample holder.
The sample stage support part, Ru is rotatably configured in the axial direction of the sample holder as a rotation axis,
Sample holder characterized by that. In the outer shell, there is no open portion connecting the first opening and the second opening along the circumferential direction of the sample holder.
The sample holder according to claim 1, characterized in that. The sample stage support is rotatable independently of the shell.
The sample holder according to claim 1 or 2, characterized in that: There is no notch in a portion of the outer shell, which exists between the first opening and the second opening along the circumferential direction of the sample holder.
The sample holder according to any one of claims 1 to 3, characterized in that. The sample support portion rotates the sample by 90 degrees between ion beam irradiation and electron beam irradiation.
The sample holder according to any one of claims 1 to 4 , characterized in that. The atmosphere blocking member is a cylindrical member provided so as to cover the outer periphery of the outer shell and movable in the axial direction of the sample holder,
A seal member externally fitted to the outer shell is provided at a position of the outer shell sandwiching the first and second openings in the axial direction of the sample holder.
When the atmosphere blocking member covers the first and second openings, the space is blocked from the open air by the close contact between the inner wall surface of the atmosphere blocking member and the seal member.
The sample holder according to any one of claims 1 to 5 , characterized in that. A transmission electron microscope observation method using a sample holder that can be shared by a transmission electron microscope and a focused ion beam processing apparatus,
The sample holder is
First and second openings which are respectively formed in mutually opposing partial regions of the cylindrical outer shell of the sample holder and from which either an electron beam or an ion beam is incident;
A sample support portion provided in a space corresponding to the first and second openings in the outer shell and configured to be able to rotate the sample with the axial direction of the sample holder as the rotation axis direction;
An atmosphere blocking member that blocks the first and second openings so as to block the space from the outside air when the electron beam and the ion beam are not irradiated;
Equipped with
The outer periphery of the first and second openings is surrounded by the outer shell,
The sample support comprises a sample table and a sample table support.
The sample table support is provided on the side of the space far from the tip of the sample holder, and the sample table is installed on the sample table support so as to extend in the axial direction of the sample holder.
The sample support unit is configured to be rotatable with the axial direction of the sample holder as the rotational axis direction .
The sample support is rotated so that the film surface of the sample is perpendicular to the incident direction of the electron beam, and the sample is read from either the first opening or the second opening. The method of observation with a transmission electron microscope, characterized in that the electron beam is irradiated to the above, and the image of the transmission electron microscope is observed.