Adhesive application jig and method for preparing specimen for transmission electron microscope observation

Abstract

To make it easier to apply an adhesive to minute areas.SOLUTION: An adhesive application tool for applying an adhesive is provided, comprising a grip portion, a probe portion attached to the grip portion and comprised of a tapered, elongate fibrous body to carry an adhesive, and a bulged portion provided at a tip end of the probe portion and formed to bulge from the probe portion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an adhesive application jig and a method for preparing a sample for observation by a transmission electron microscope. [Background technology]

[0002] With the development of the electronics industry, there is a growing demand for precise information on the physical properties and state of change of various materials used in this field. Observation using a transmission electron microscope (hereinafter also referred to as "TEM") is considered to be an effective means of obtaining such information.

[0003] When observing materials made of various materials and having various shapes, such as sheet or flake shapes, using a TEM, it is necessary to process the materials in advance into TEM observation samples so that they can be loaded into a TEM sample holder. For example, Patent Document 1 discloses a method for processing a laminate including sample pieces by applying an adhesive to a substrate, placing sample pieces on the substrate, placing spacers so as to sandwich the sample pieces from both sides, and further applying an adhesive thereon. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-98088 Summary of the Invention [Problem to be solved by the invention]

[0005] The use of sheet meshes has been investigated as a method for processing thin sheet-like or scale-like samples into samples for TEM observation. Specifically, the sample is placed in the holes of the sheet mesh, an adhesive is filled between the sheet mesh and the sample, and the adhesive is allowed to harden.

[0006] However, the inventors' investigations revealed that because the holes in the sheet mesh are small and the gap between the sheet mesh and the sample is also narrow, it is difficult to apply and fill such a small, minute area with adhesive.

[0007] The present invention has been made in view of the above-mentioned problems, and has an object to provide a technique for easily applying an adhesive to a minute area. [Means for solving the problem]

[0008] A first aspect of the present invention is An adhesive application jig for applying an adhesive, A gripping portion; a probe portion attached to the grip portion and configured as a tapered, elongated fiber body for carrying the adhesive; a protruding portion provided on the tip side of the probe portion and protruding from the probe portion, This is a jig for applying adhesive.

[0009] A second aspect of the present invention is a method for producing a composition comprising the steps of: The size of the protrusion is 1.3 times or more and 3.0 times or less the diameter of the probe portion.

[0010] A third aspect of the present invention is the first or second aspect, The diameter of the probe portion is 10 μm or more and 70 μm or less, The size of the raised portion is 13 μm or more and 200 μm or less.

[0011] A fourth aspect of the present invention is the method according to any one of the first to third aspects, The raised portion is formed from a cyanoacrylate resin.

[0012] A fifth aspect of the present invention is placing sample pieces in holes in a sheet mesh; a step of preparing an adhesive application jig including a gripping portion, a probe portion for carrying adhesive, the probe portion being attached to the gripping portion and consisting of a tapered, elongated fiber body, and a protruding portion provided on the tip side of the probe portion and protruding from the probe portion; After the adhesive is applied to the tip of the probe of the adhesive application jig, the sheet mesh and The sample piece and applying the adhesive to a gap formed between the adhesive and the substrate, and filling the gap with the adhesive. This is a method for preparing a sample for observation by a transmission electron microscope.

[0013] A sixth aspect of the present invention is the method according to the fifth aspect, The width of the gap is 200 μm or less.

[0014] A seventh aspect of the present invention is the fifth or sixth aspect, The adhesive comprises an epoxy resin.

[0015] An eighth aspect of the present invention is A step of subjecting a portion of a central portion of the sheet-like sample to thinning; a step of preparing an adhesive application jig including a gripping portion, a probe portion for carrying adhesive, the probe portion being attached to the gripping portion and consisting of a tapered, elongated fiber body, and a protruding portion provided on the tip side of the probe portion and protruding from the probe portion; a step of applying the adhesive to both ends of the sheet-like sample having the partial region thinned after the adhesive is applied to the tip of the probe portion of the adhesive application jig; and placing a ring-shaped reinforcing member on the sheet sample via the adhesive so that the thinned partial region is exposed. This is a method for preparing a sample for observation by a transmission electron microscope. [Effects of the Invention]

[0016] According to the present invention, adhesive can be easily applied to minute gaps. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram of an adhesive application jig according to one embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged view of a part of the probe portion in FIG. [Figure 3] FIG. 3 is a perspective view of a sheet mesh having one slot hole. [Figure 4] FIG. 4 is a perspective view of the sample to be observed. [Figure 5] FIG. 5 is a perspective view of a sample piece obtained by trimming a sample to be observed. [Figure 6] FIG. 6 is a cross-sectional view of the sample piece placed in the hole of the sheet mesh. [Figure 7] FIG. 7 is a diagram for explaining application and filling of adhesive into gaps using a jig. [Figure 8] FIG. 8 is a diagram for explaining the thinning process of the hardened sample, where (a) is a perspective view and (b) is a cross-sectional view. [Figure 9] FIG. 9 is a diagram showing a schematic configuration of a sample for observation with a transmission electron microscope, where (a) is a perspective view and (b) is a cross-sectional view. [Figure 10] FIG. 10 is a diagram for explaining application of adhesive to a sheet-like sample. [Figure 11] FIG. 11 is a diagram illustrating the adhesive fixation of the ring-shaped reinforcing member to the sheet-shaped sample. [Figure 12] FIG. 12 is a diagram showing the adhesive applied to the adhesive application jig of Example 1. [Figure 13] FIG. 13 is a diagram showing the adhesive applied to the adhesive application jig of Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0018] Adhesive application methods include those using microsyringes and dispensers, but these methods cannot easily apply adhesive to small areas for the following reasons. Although microsyringes are inexpensive, the operator's hands may tremble when dispensing the adhesive from the microsyringe, making it difficult to accurately apply the adhesive to the desired area. While dispensers can reduce the hand tremors associated with microsyringes, commonly used dispenser devices tend to have thick needles (e.g., 0.23 mm) and thus cover a large application area. If the application area is large, the adhesive may be applied not only to the gaps but also to the surface of the sample, lengthening the processing time for thin section processing.

[0019] For example, when a sample is placed in the hole of the above-mentioned sheet mesh and adhesive is applied, the hole of the sheet mesh varies depending on the type, but at the smallest, it is about 1 mm in diameter, and the diameter of the sample placed in the hole is about 0.9 mm. Therefore, the gap between the sheet mesh and the sample is a narrow area with a width of about 20 to 80 μm. In such a small area, the above-mentioned application method may not be able to easily apply adhesive to the gap.

[0020] For this reason, the present inventors investigated an adhesive application tool that can easily apply adhesive to minute areas. They focused on a probe-like, elongated fiber that tapers toward its tip as a component for carrying and applying adhesive. They constructed an application tool by attaching a probe portion consisting of a single fiber to a gripper, and investigated its application properties.

[0021] However, in this case, when the adhesive was scooped up with the probe, the adhesive moved from the tip to the base of the probe due to surface tension, making it impossible to retain the adhesive at the tip, making it difficult to apply the adhesive to a small area.

[0022] Based on this, we further investigated ways to prevent the adhesive from flowing and found that providing a bump-like protrusion on the tip of the probe was effective. This protrusion allows the adhesive to be held at the tip.

[0023] The present invention was made based on the above findings.

[0024] <One embodiment of the present invention> An adhesive application jig according to one embodiment of the present invention will be described below. Fig. 1 is a schematic diagram of an adhesive application jig according to one embodiment of the present invention. Fig. 2 is an enlarged view of a part of the probe portion in Fig. 1.

[0025] The adhesive application jig (hereinafter simply referred to as the jig) of this embodiment is used to apply and fill adhesive to a small area, and can be used, for example, to apply and fill adhesive to gaps formed when a sample is placed in a small hole in a sheet mesh. Specifically, as shown in Figure 1, the jig 1 includes a gripping portion 11, a probe portion 12, and a raised portion 13.

[0026] The grip portion 11 supports the probe portion 12 and serves as a handle when the operator uses the jig. There are no particular limitations on the grip portion 11 as long as it can be attached to the probe portion 12 and is easy to handle. For example, as shown in FIG. 1, a rod-shaped member can be used. Examples of rod-shaped members that can be used include toothpicks, bamboo sticks, and resin sticks. There are also no particular limitations on the length, diameter, and shape of the grip portion 11, and these can be changed as appropriate.

[0027] The probe portion 12 is attached to the grip portion 11 and is supported by an adhesive. The probe portion 12 is made of a single, elongated, tapered fiber body and is supported by an adhesive. The probe portion 12 has a diameter (fiber diameter) that allows adhesive to be applied to a very small, narrow area. The probe portion 12 may be attached to the grip portion using, for example, an adhesive.

[0028] The fibrous material constituting the probe portion 12 is not particularly limited as long as it can be supported by adhering an adhesive, and for example, resin fibers or stiff fibrous materials such as eyelashes or animal hair can be used.

[0029] The diameter of the fibrous body constituting the probe portion 12 is preferably smaller than the width of the gap between the sheet mesh and the sample, specifically, preferably 10 μm to 70 μm. The length of the fibrous body is not particularly limited, but is preferably 3 mm to 6 mm. By setting the diameter and length of the fibrous body within the above ranges, it is possible to easily apply the agent to minute gaps while maintaining the ease of handling of the jig 1.

[0030] As shown in FIGS. 1 and 2 , the raised portion 13 is provided on the tip side of the probe portion 12. The raised portion 13 is formed in a bump shape so as to protrude from the probe portion 12. The raised portion 13 makes it possible to locally increase the diameter of the tapered tip of the probe portion 12. When the tip of the probe portion 12 is immersed in adhesive, the raised portion 13 prevents the adhesive from migrating toward the base side (the grip portion 11 side) of the probe portion 12, allowing the adhesive to be held at the tip of the probe portion 12. The mechanism by which the raised portion 13 holds the adhesive is unclear, but it is presumed that the raised portion 13 creates a step between the probe portion 12 and the raised portion 13, or that the raised portion 13 has a larger diameter than the probe portion 12 and therefore acts to block the adhesive and prevent it from spreading to the probe portion 12.

[0031] The position where the raised portion 13 is formed is not particularly limited as long as it is on the tip side of the probe portion 12, but the raised portion 13 is preferably provided at the tip of the probe portion 12 so that the tip of the probe portion 12 does not protrude from the raised portion 13. By providing the raised portion 13 in this manner, the adhesive can be more reliably supported on the tip of the probe portion 12.

[0032] The material for forming the raised portion 13 is preferably a resin because of its ease of formation. Examples of resins that can be used include room temperature curing resins, UV curing resins, and two-component curing resins. Examples of room temperature curing resins that can be used include cyanoacrylate resins that are cured by moisture. Examples of UV curing resins that can be used include acrylic resins and epoxy resins that are cured by ultraviolet light. Examples of two-component curing resins that can be used include two-component mixed epoxy resins. From the viewpoints of ease of handling and ease of forming the raised portion 13, room temperature curing resins such as cyanoacrylate resins are preferred. The raised portion 13 can be formed using a room temperature curing resin by, for example, immersing the tip of the probe portion 12 made of a fibrous body in a liquid or gel resin and curing the resin.

[0033] The shape of the raised portion 13 is not particularly limited as long as it has a diameter larger than that of the probe portion 12. For example, it may be not only spherical as shown in FIG. 2, but also triangular pyramid or T-shaped. From the viewpoint of more reliably supporting the adhesive, the size of the raised portion 13 is preferably 1.3 to 3.0 times the diameter of the probe portion 12. The size of the raised portion 13 refers to the size of the point of the raised portion 13 with the largest diameter.

[0034] (Method for preparing samples for transmission electron microscope observation) Next, as a specific example of applying adhesive to a minute area using the jig 1 described above, a method of preparing a sample for observation by a transmission electron microscope using a sheet mesh will be described.

[0035] First, a sheet mesh 20 as shown in FIG. 3 is prepared. Conventionally, the sheet mesh 20 is used to load a sample into a TEM. It is a small, circular wire mesh on which the sample to be observed is placed. The sheet mesh 20 has a hole 22 formed in the center of a main body 21. In this embodiment, the sheet mesh 20 is used as a support member for supporting and fixing a trimmed sample piece. The size of the sheet mesh 20 is not particularly limited as long as it can be loaded into a TEM sample holder, but an outer diameter of 3 mm is preferable, for example. Furthermore, the thickness of the sheet mesh 20 is preferably 10 μm or more and 50 μm or less from the viewpoints of mechanical strength and ease of processing by ion milling (IM), which will be described later.

[0036] The sample pieces are inserted into the holes 22 of the sheet mesh 20. While FIG. 3 shows the sheet mesh 20 with one slot as the hole 22, the number, size, and shape of the holes 22 can be selected as desired depending on the size and shape of the sample pieces. The hole 22 may be a single hole, or the number of holes 22 may be two or more. From the viewpoint of facilitating processing by IM (internal magnetic resonance), described below, it is generally preferable to use a disk-shaped sheet mesh 20 with a single hole or one slot as the hole 22. The size of the hole 22 may be, for example, approximately 1 mm × 2 mm if it is a slot, and a diameter of 0.3 mm or more and 1 mm or less if it is a single hole. This size facilitates sample trimming, described below, and makes it easier to ensure an observation field during TEM observation, described below.

[0037] The material of the sheet mesh 20 can be appropriately selected from metals such as copper, nickel, gold, molybdenum, copper, carbon, polymer materials, etc. The material of the sheet mesh 20 is preferably selected from those having a spectrum that does not overlap with the spectrum of X-rays generated from the sample piece when observed with a TEM, which will be described later.

[0038] Next, a sample to be observed is prepared. This sample may contain one or more of, for example, metal oxides, metal hydroxides, metal carbonates, metal nitrides, composite oxides, composite hydroxides, composite carbonates, composite nitrides, and various ceramic powders. The shape of the sample is not particularly limited, and in this embodiment, a sheet-like or flake-like sample may also be used. For example, as shown in FIG. 4, a sheet-like sample 30 may be used, in which a metal oxide-containing coating 32 is provided on one side of a metal foil 31.

[0039] Next, the sample 30 is trimmed to a size that can be placed in the hole 22 of the sheet mesh 20, producing a sample piece 33 as shown in FIG. 5. The size of the sample piece 33 can be adjusted appropriately depending on the diameter of the hole 22 of the sheet mesh 20 used, and it is preferable to set it to a size that can reliably fit into the hole 22. Considering the thinning process using an ion beam described below, it is preferable that the gap between the sample piece 33 and the hole 22 be small. Specifically, the size of the sample piece 33 can be adjusted depending on the diameter of the hole 22 so that the gap width is 200 μm or less. Furthermore, the shape of the sample piece 33 can be arbitrary, but it is preferable that it be similar to the shape of the hole 22. For example, in FIG. 5, the sample piece 33 is trimmed to an octagonal shape so that it can be inserted into the slot that serves as the hole 22 shown in FIG. 8. Similarly, when the hole 22 is a single hole, it is preferable that the sample piece 33 be octagonal.

[0040] Next, the sample piece 33 is fixed to the sheet mesh 20 .

[0041] Specifically, as shown in Fig. 6, first, the sheet mesh 20 is placed on the sheet 40. Next, the sample piece 33 is placed in the center of the hole 22. At this time, the sample piece 33 is positioned so that the surface to be observed of the sample piece 33 (here, the coated body 32) is in contact with the sheet 40. This makes it possible to make the surface to be observed of the sample piece 33 flush with the surface of the sheet mesh 20, and to prevent the surface to be observed from protruding from the sheet mesh 20.

[0042] The position of the sample piece 33 in the hole 22 is not particularly limited, but it is preferable to install the sample piece 33 so that it is off-center from the center of the hole 22. In other words, in FIG. 6, the sample piece 33 is installed so that it is biased toward the frame portion of the sheet mesh 20 within the hole 22. This allows the sample piece 33 to be installed so that one gap between the sheet mesh 20 and the sample piece 33 is narrower than the other gap. The gap width is preferably, for example, 20 μm or more and 200 μm or less. Note that this gap width refers to the narrowest gap between the sheet mesh 20 and the sample piece 33.

[0043] The sheet 40 on which the sheet mesh 20 is placed is preferably made of silicone resin. The silicone resin sheet 40 can adsorb the sheet mesh 20 and the sample piece 33, preventing the sample piece 33 from shifting position when applying adhesive. Furthermore, it prevents the hardened adhesive from sticking, making it easy to handle after hardening.

[0044] Next, using the jig 1 described above, adhesive is applied to fill the gap between the inner wall of the hole 22 and the sample piece 33. First, the tip of the probe portion 12 of the jig 1 is immersed in the adhesive. At this time, the raised portion 13 provided on the tip side of the probe portion 12 prevents the adhesive from migrating toward the base side of the probe portion 12, allowing the adhesive to be carried at the tip of the probe portion 12. Next, as shown in FIG. 7 , the probe portion 12 carrying adhesive 50 is brought close to the gap, and the adhesive 50 is applied to the gap and the gap is filled with adhesive 50.

[0045] The adhesive 50 to be filled into the gaps is not particularly limited as long as it is liquid or gel-like under the atmosphere at the time of filling and can fix the sample pieces 33 in the holes 22 of the sheet mesh 20 upon hardening. For example, known adhesives such as room temperature hardening types, heat hardening types, and UV hardening types that harden upon UV irradiation can be used. Among these, heat hardening types are preferred because they provide the desired strength for TEM observation when hardened. As a heat hardening type, epoxy resin is preferred for ease of operation. The viscosity of the adhesive is not particularly limited as long as it is liquid and can be suitably filled into the gaps.

[0046] Next, the adhesive 50 filled in the gap is cured, and the sheet 40 is peeled off. In this way, a cured sample is obtained. Note that the curing method may be changed as appropriate depending on the type of adhesive 50.

[0047] The obtained cured sample is constructed by inserting the sample piece 33 into the hole 22 of the sheet mesh 20 and filling the gap between the inner wall of the hole 22 and the sample piece 33 with the cured product of the adhesive 50. The surface of the sample piece 33 to be observed is flush with the surface of the sheet mesh 20. In the cured sample 60, the sample piece 33 is preferably positioned offset in the hole 22 of the sheet mesh 20.

[0048] The hardened sample is then thinned using IM so that it can be loaded into a TEM.

[0049] 8(a) and 8(b), a disk-shaped hardened sample 60 is first loaded into the IM so that the side of the sheet mesh 20 faces the ion gun of the IM. At this time, the sheet mesh 20 also functions as a shielding plate, so the shielding plate provided on the IM can be omitted.

[0050] Next, the ion gun irradiates the hardened sample 60 with an ion beam 100. At this time, the portion 20a of the sheet mesh 20 on the ion gun side (the dotted line portion 20a in the figure) functions as a shielding plate. This prevents the surface of the sample piece 33 to be observed from being cut too much. As a result, the portion 20a of the sheet mesh on the ion gun side and the sample piece 33 of the hardened sample 60 are cut by the ion beam 100, resulting in a thin section. In this way, a sample for TEM observation is obtained.

[0051] While the method for positioning the hardened sample 60 in the IM during thinning is not particularly limited, it is preferable to load the hardened sample 60 into the IM so that the sample pieces 33, which are positioned to one side in the hole 22, are positioned on the side irradiated with the ion beam 100. In other words, it is preferable to load the hardened sample 60 so that the narrowest gap between the hole 22 and the sample pieces 33 is positioned on the side irradiated with the ion beam 100. The adhesive 50 is more easily scraped off by the ion beam 100 than the sheet mesh 20. Therefore, if the widest gap between the hole 22 and the sample pieces 33 (the area where the adhesive 50 is filled) is positioned on the ion beam 100 side, the adhesive 50 may be scraped off during thinning, causing the sample pieces 33 to detach from the sheet mesh 20 or to become displaced. In this regard, by placing the hardened sample 60 so that the narrowest gap is positioned on the ion beam 100 side, the sample pieces 33 can be thinned while suppressing detachment and displacement of the sample pieces 33.

[0052] 9(a) and (b), a sample for TEM observation is prepared by partially thinning a sample piece 33 and forming a hole 71 in the center, resulting in a thickness suitable for observation with a TEM. The thickness of the thinned portion 33a of the sample piece 33 is preferably, for example, 0.01 μm or more and 0.1 μm or less. The thinned portion 33a of the sample piece 33 is preferably, for example, an area of ​​about 0.5 × 1 mm, to ensure a sufficient field of view when observing with a TEM.

[0053] The ion gun is suitably moved back and forth (swung) around the center of the sheet mesh 20, or the sheet mesh 20 is rotated eccentrically. This movement allows the ion beam 100 to be irradiated onto the hardened sample 60 while varying within a range of θ, which is the range of variation in the angle of incidence of the ion beam 100 when the ion beam 100 is incident on the hardened sample 60. The value of the variation range θ when the ion beam 100 is incident on the hardened sample 60 is 0° to 20°, preferably in the range of approximately 0.5° to 5°. The ion beam 100 can be, for example, argon, gallium, or xenon.

[0054] Furthermore, when thinning the hardened sample 60, the portion 20a of the sheet mesh 20 on the ion gun side may be sputtered, and the sheet mesh 20 may lose its function as a shielding plate, although it still has the strength required for the sheet mesh 20. In such cases, it is advisable to irradiate the ion beam 100 from two or more directions, rather than just one direction, to perform the thinning process.

[0055] (TEM observation) Next, the obtained TEM observation sample 70 is loaded into a TEM for observation. Since the periphery of the sample piece 33 of the TEM observation sample 70 is surrounded by the sheet mesh 20, the TEM observation sample 70 can be loaded directly into the TEM sample holder while suppressing mechanical shock to the sample piece 33. The TEM observation sample 70 has a thinned portion 33a of the sample piece 33 that has a thickness suitable for observation in a TEM and is large enough to ensure a sufficient observation field, allowing for high-precision observation.

[0056] If the observation results in inaccurate observation due to the observation orientation being incorrect in the specimen piece 33 or the sliced ​​portion 33a being too thick, additional processing may be performed on the TEM observation specimen 70. The TEM observation specimen 70 may be removed from the TEM and placed in the IM, and irradiated with the ion beam 100 from a position rotated clockwise (or counterclockwise) by a desired angle from the previous ion beam irradiation (for example, rotated 90° or 180° from the previous irradiation). After irradiation with the ion beam 100, the TEM observation specimen 70 is then placed in the TEM again for observation. In this way, TEM observation and additional processing can be easily performed as many times as desired.

[0057] <Effects of this embodiment> According to this embodiment, one or more of the following effects are achieved.

[0058] According to the adhesive application jig 1 of this embodiment, the protrusion 13 is provided on the tip side of the probe portion 12, so that when the adhesive 50 is applied to the tip of the probe portion 12, the tip can carry the adhesive 50. Therefore, when a sample piece 33 is placed in the hole 22 of the sheet mesh 20, the adhesive 50 can be easily applied and filled into a minute gap formed between the side wall of the hole 22 and the sample piece 33.

[0059] In the jig 1, the size of the raised portion 13 is preferably 1.3 to 3.0 times the diameter of the probe portion 12. This makes it possible to maintain the ability of the tip of the probe portion 12 to support the adhesive 50 while suppressing bending of the probe portion 12 caused by an excessively large raised portion 13.

[0060] It is also preferable that the diameter of probe portion 12 is 10 μm or more and 70 μm or less, and the size of raised portion 13 is 13 μm or more and 200 μm or less. By making probe portion 12 have a predetermined diameter, it becomes easier to apply adhesive 50 to a minute gap having a width of 200 μm or less, for example, and by making raised portion 13 have a predetermined size, it becomes easier to hold adhesive 50 at the tip of probe portion 12.

[0061] The raised portion 13 is preferably formed from a cyanoacrylate resin. Cyanoacrylate resin makes it easier to form the raised portion 13 at the tip of the elongated probe portion 12 and also makes it easier for the tip of the probe portion 12 to support the adhesive 50.

[0062] According to the method for preparing a TEM observation sample 70 of this embodiment, the sample piece 33 is first placed in the hole 22 of the sheet mesh 20. Then, the adhesive 50 is applied and filled into the minute gap between the sidewall of the hole 22 and the sample piece 33 using the jig 1 described above. The adhesive 50 is then cured to prepare a hardened sample 60. Since the application of the adhesive 50 reduces adhesion of the adhesive 50 to the surface of the sample piece 33, there is no need to remove excess adhesive 50 using IM, and thinning can be performed more efficiently. The sample piece 33 in the hardened sample 60 is then irradiated with an ion beam 100 to thin the sample piece 33, thereby obtaining a TEM observation sample 70. According to the TEM observation sample 70, the thinned portion 33a of the sample piece 33 can be formed to a thickness suitable for TEM observation and large enough to ensure a sufficient observation field. This allows for high-precision observation using a TEM.

[0063] Furthermore, the obtained TEM observation sample 70 has only been subjected to thinning processing by IM, and no mechanical processing such as cutting with a knife has been performed, so the possibility of mechanical damage to the TEM observation sample 70 can be avoided, and the production process can be simplified, thereby increasing the efficiency of producing the TEM observation sample 70.

[0064] Furthermore, in the obtained TEM observation sample 70, the sliced ​​portions 33a of the sample piece 33 become embrittled, but the sample piece 33 is placed in the holes 22 of the sheet mesh 20 and is surrounded by the sheet mesh 20, so that it is possible to prevent the sliced ​​portions 33a from being subjected to direct mechanical shock. This improves the handleability of the TEM observation sample 70 including the sample piece 33 that becomes embrittled due to slicing.

[0065] In the TEM observation sample 70, it is preferable to adjust the size of the sample piece 33 according to the diameter of the hole 22 so that the width of the gap formed between the hole 22 of the sheet mesh 20 and the sample piece 33 is 200 μm or less. The jig 1 allows adhesive to be efficiently filled into minute gaps with a width of 200 μm or less. By making the size of the sample piece 33 closer to the diameter of the hole 22 in this way, processing can be easily performed when thinning the hardened sample 60 with an ion beam.

[0066] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit of the present invention.

[0067] In the above embodiment, a case has been described in which adhesive is applied to minute gaps when fixing minute sample pieces 33 obtained by trimming sample 30 to sheet mesh 20, but the present invention is not limited to this. For example, after sample 30 has been thinned directly using an ion milling device, when a reinforcing member is attached before the sample is subjected to TEM, the adhesive application jig 1 described above can be used to adhesively fix sample 30 to the reinforcing member. This point will be described in detail below.

[0068] First, as shown in FIG. 10 , a sheet-shaped sample 80 is extracted as a sample 30 thinned by an ion milling apparatus. The sheet-shaped sample 80 is supported at both ends by a sample holder 90. A portion of the central region of the sheet-shaped sample 80 is thinned, forming a thinned region 80a. The sheet-shaped sample 80 is then removed from the sample holder 90 and subjected to TEM. However, the thinned sheet-shaped sample 80 may lack strength and be difficult to handle. Therefore, a reinforcing member is attached to the thinned sheet-shaped sample 80. As shown in FIG. 11 , a ring-shaped reinforcing member 81 is used as this reinforcing member, so long as it is ring-shaped. For example, a C-shaped or O-shaped ring can be used. The material of the ring-shaped reinforcing member 81 is not particularly limited, but examples include Mo and SUS. The size of the sheet sample 80 is not particularly limited, but may be, for example, 2.5 mm to 2.8 mm wide, 0.5 mm to 1.0 mm long, and 0.05 mm to 0.2 mm thick. The size (outer diameter) of the ring-shaped reinforcing member 81 may be selected appropriately depending on the size of the TEM sample stage, for example, 2.5 mm to 3.5 mm, preferably 3.05 mm. The size (inner diameter) of the ring-shaped portion of the ring-shaped reinforcing member 81 may be selected appropriately depending on the size of the sheet sample 80 and the size of the sliced ​​region 80a, for example, 1.5 mm to 2.5 mm.

[0069] Next, a ring-shaped reinforcing member 81 is attached to the thinned sheet sample 80. Specifically, as shown in FIGS. 10 and 11 , adhesive 50 is applied to both ends of the sheet sample 80 using the adhesive applicator 1 described above, and the ring-shaped reinforcing member 81 is placed on top of the adhesive so that the thinned region 80a is exposed. If a large amount of adhesive 50 is applied, the applied area becomes wide, and the adhesive 50 spreads toward the sample holder 90, the sheet sample 80 becomes fixed to the sample holder 90 and becomes difficult to remove. In this regard, the adhesive applicator 1 allows an appropriate amount of adhesive 50 to be applied, preventing excessive spreading of the applied area and preventing the adhesive 50 from spreading toward the sample holder 90.

[0070] After the adhesive 50 has solidified, the sample holder 90 is heated, the ring-shaped reinforcing member 81 is lifted, and the sheet-shaped sample 80 is removed from the sample holder 90. The sheet-shaped sample 80 with the ring-shaped reinforcing member attached can be introduced into a TEM as a sample for TEM observation, and TEM observation can be performed.

[0071] In the above embodiment, the jig is used to apply adhesive, but it may also be used to apply a liquid other than adhesive to a minute area, such as ink containing a pigment. [Example]

[0072] The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

[0073] Example 1 First, an adhesive application jig was prepared. In this example, an eyelash probe was used, with a probe attached to a gripping portion. The eyelash probe is a tool in which an eyelash is adhesively fixed as a probe portion to one end of a toothpick serving as a gripping portion. It is generally used to move thin specimens in a TEM. In this example, the tip of the eyelash of this eyelash probe was immersed in Aron Alpha (registered trademark) manufactured by Toa Gosei Co., Ltd., and then pulled out. A spherical mass of Aron Alpha was attached to the tip of the eyelash, which was then cured to form a ball-shaped raised portion. The size of the raised portion was approximately 88 μm, approximately 1.4 times the diameter of the tip of the eyelash (63 μm).

[0074] In addition, the following samples, adhesives, and sheet meshes to be observed were prepared.

[0075] The sample to be observed was a sheet-like metal foil (thickness: about 10 μm) coated with a layer of transition metal oxide powder and conductive additives, etc., with a thickness of about 10 μm. The surface with the coating containing the transition metal oxide powder and conductive additives, etc., was the observation surface.

[0076] As the adhesive, an epoxy resin (G2) manufactured by GATAN was prepared.

[0077] The sheet mesh used was manufactured by Oken Shoji Co., Ltd. (#09-1059). This is a one-slot (1 mm x 2 mm) sheet mesh made of molybdenum (Mo) whose EDS spectrum does not overlap with that of the sample being observed. The thickness of the sheet mesh was 12 μm.

[0078] Next, the sample to be observed was trimmed to a size (long octagonal shape, 0.9 mm long x 1.7 mm wide) that would fit into the hole (slot) of the sheet mesh, to obtain a sample piece.

[0079] Next, the sheet mesh was placed on a silicone wrap (Kitchen Silicone C008, manufactured by Daiso Co., Ltd.) and adsorbed onto the sheet mesh. The trimmed sample piece was placed in the slot of this sheet mesh. At this time, the surface of the sample piece on which the coating body was provided faced the silicone wrap, and the sample piece was placed with the long side of the slot aligned with the long side of the sample piece. The width of the gap between the inner wall of the slot of the sheet mesh and the sample piece was 50 μm.

[0080] Next, adhesive was applied and filled into the gap between the inner wall of the slot in the sheet mesh and the sample piece. In this example, an eyelash probe with a ball-shaped raised portion at the tip was immersed in the adhesive to apply the adhesive to the eyelash. As shown in Figure 12, the adhesive (A), which had been rounded by surface tension, remained at the raised tip of the eyelash (B), preventing it from migrating toward the base of the eyelash. The tip of the eyelash was then moved into the gap between the inner wall of the slot and the sample piece, and the adhesive was applied and filled into the gap. After filling, the adhesive was cured by heating on a hot plate at 125°C for 15 minutes, and the silicone wrap was peeled off to obtain a cured sample. An epoxy resin adhesive ("Bond Quick 5" manufactured by Konishi Co., Ltd., viscosity 50,000 cP / 25°C) was used as the adhesive.

[0081] Next, the hardened sample was introduced into an ion milling device (JEOL Ltd.'s "Ion Slicer IB09060CIS"). Instead of using the shielding plate attached to the device, the sheet mesh on the hardened sample was used as the shielding plate. The hardened sample was then irradiated with argon ions from an ion gun. The hardened sample was tilted 2° relative to the argon ions, and the metal foil side of the sample piece in the hardened sample was irradiated with argon ions at 6 kV for 1 hour. Subsequently, both sides of the hardened sample were irradiated with argon ions at 6 kV, 5 kV for 1 hour each, and 3 kV for 15 minutes, to thin the hardened sample. This produced the TEM observation sample of Example 1.

[0082] Finally, the sample for TEM observation was loaded into a TEM sample holder and placed in a TEM (JEM-ARM200F, manufactured by JEOL Ltd.). The portion of the sample for TEM observation that had been thinned by argon ions had a thickness suitable for TEM observation, and a sufficient observation field was ensured, allowing for high-precision observation of the sheet-like sample.

[0083] (Comparative Example 1) In Comparative Example 1, a TEM observation sample was prepared in the same manner as in Example 1, except that the eyelash probe was used as is without providing a resin protrusion at the tip of the eyelash probe. However, when the eyelash probe was immersed in the adhesive as is, as shown in Figure 13, the adhesive (A) migrated toward the base of the eyelash (B), and it was confirmed that the adhesive could not be applied to the tip of the eyelash. The reason for this is unclear, but it is thought that because the eyelashes are tapered, the rounded adhesive at the tip was attracted to the lump of adhesive formed at the base, causing the adhesive to migrate toward the base. Therefore, it was confirmed that the jig of Comparative Example 1 could not easily apply or fill adhesive into tiny gaps.

[0084] As described above, it has been confirmed that by providing a raised portion at the tip of a tapered fibrous body in an adhesive application jig, it is possible to make it easier to support the adhesive, and to easily apply the adhesive to small areas such as tiny gaps. [Explanation of symbols]

[0085] 1 Adhesive application jig 11 Gripping part 12 Probe section 13 Ridge 20 Sheet Mesh 21 Main body 22 Hole 30 samples 31 Metal foil 32 Applicator 33 Sample piece 33a Thinned section 40 sheets 50 Adhesive 60 hardened samples 70 Transmission electron microscope specimens 71 Perforation 80 Sheet samples 80a thin section area 81 Ring-shaped reinforcing member 90 Sample holder

Claims

1. An adhesive application jig for applying an adhesive, A gripping portion; a probe portion attached to the grip portion and configured as a tapered, elongated fiber body for carrying the adhesive; a protruding portion provided on the tip side of the probe portion and protruding from the probe portion, Adhesive application jig.

2. The size of the raised portion is 1.3 times or more and 3.0 times or less the diameter of the probe portion. The adhesive application jig according to claim 1 .

3. The diameter of the probe portion is 10 μm or more and 70 μm or less, The size of the raised portion is 13 μm or more and 200 μm or less. The adhesive application jig according to claim 1 or 2.

4. The raised portion is formed from a cyanoacrylate resin. The adhesive application jig according to any one of claims 1 to 3.

5. placing sample pieces in holes in a sheet mesh; a step of preparing an adhesive application jig including a gripping portion, a probe portion for carrying adhesive, the probe portion being attached to the gripping portion and consisting of a tapered, elongated fiber body, and a protruding portion provided on the tip side of the probe portion and protruding from the probe portion; and after the adhesive is applied to the tip of the probe portion of the adhesive application jig, the adhesive is applied to a gap formed between the sheet mesh and the sample piece, thereby filling the gap with the adhesive. A method for preparing samples for transmission electron microscopy.

6. The width of the gap is 200 μm or less.

6. A method for preparing a sample for transmission electron microscope observation according to claim 5.

7. The adhesive comprises an epoxy resin. The adhesive application jig according to claim 5 or 6.

8. A step of subjecting a portion of a central portion of the sheet-like sample to thinning; a step of preparing an adhesive application jig including a gripping portion, a probe portion for carrying adhesive, the probe portion being attached to the gripping portion and consisting of a tapered, elongated fiber body, and a protruding portion provided on the tip side of the probe portion and protruding from the probe portion; a step of applying the adhesive to both ends of the sheet-like sample having the partial region thinned after the adhesive is applied to the tip of the probe portion of the adhesive application jig; and placing a ring-shaped reinforcing member on the sheet sample via the adhesive so that the thinned partial region is exposed. A method for preparing samples for transmission electron microscopy.

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