Specimen holder, intermembrane distance adjustment mechanism, and charged particle beam device

Abstract

The present invention reliably holds a liquid or gel sample using a sample holder, improving the qualification rate of observation using a charged particle beam device. The sample holder (101) includes: a first component (102) having a lid component (111) and a first chip (105) having a first window (123) with a stacked film including a first insulating film (104); and a second component (103) having a base material (127) with a first bottom sealing surface (203) and a second bottom sealing surface (200), an electrode (108) disposed on the base material, and a second chip (107) having a second window (124) with a second insulating film (106), and held on the second bottom sealing surface via a second seal (119) such that the second window faces the electrode. The first component and the second component are combined, and a first seal is compressed between the first bottom sealing surface and the upper sealing surface of the lid component, whereby a region inside the first seal is kept airtight with respect to a region outside the first seal.

Description

Technical Field

[0001] The present invention relates to a specimen holder for a charged particle beam apparatus that observes the shape or material of a specimen using a detection signal generated by irradiating a charged particle beam. More specifically, it relates to a specimen holder for a charged particle beam apparatus that can observe a liquid or gel-like specimen in a non-invasive state. Background Art

[0002] A scanning electron microscope (SEM), which is one of the charged particle beam apparatuses, is widely used not only for observing material specimens such as metals and ceramics but also as a tool for observing biological specimens with high resolution.

[0003] Generally, in the above-described apparatus, the chamber is evacuated, and the specimen is placed in a vacuum atmosphere and photographed. Since the electron beam is scattered by gas molecules such as air and liquid molecules, the passage path of the electron beam is preferably maintained in a vacuum atmosphere. On the other hand, if placed in a vacuum atmosphere, biochemical specimens and liquid specimens are damaged or their states change, so it is considered difficult to observe them in a non-invasive state. However, there is a great demand for non-invasive observation of specimens. In recent years, electron microscopes that can observe the specimen to be observed in an atmospheric pressure environment or in a liquid environment have been developed.

[0004] In the observation systems disclosed in Patent Documents 1 and 2, on the other main surface of a first insulating film whose one main surface is a holding surface for observing a specimen, a laminated conductive film is provided, and an electron beam is irradiated from the side of the conductive film in a state where the conductive film is at a ground potential or a predetermined bias voltage is applied. Due to the irradiated electron beam, a local potential change is generated on one main surface of the first insulating film. Using a detection electrode provided below a second insulating film disposed on the opposite side across the observation specimen, a signal based on this potential change is detected.

[0005] The signal based on the potential change generated in the first insulating film detected by the detection electrode propagates in the observation specimen. The propagation ability of the signal at this time varies depending on the observation specimen. For example, water has a relatively high relative dielectric constant of about 80, which allows the signal to propagate well, while a biological specimen has a relatively low relative dielectric constant of about 2 to 3, and the propagation ability of the signal is low. Therefore, based on the intensity difference of the potential change signal propagating in the observation specimen, the biological specimen in the aqueous solution can be observed with high contrast without performing a staining treatment or an immobilization treatment. This method does not require direct irradiation of a high-energy electron beam onto the specimen to be observed, and thus is suitable for non-destructive observation of biological specimens in a liquid.

[0006] In addition, Patent Document 3 discloses a transmission electron microscope (TEM: Transmission Electron Microscope), a scanning transmission electron microscope (STEM: Scanning Transmission Electron Microscope), an existing TEM-type holder, and a sample holder for a SEM using a workbench, which observe a sample by transmitting an electron beam serving as a probe and detecting the transmitted electrons. The sample holder holds a liquid sample or a gas sample in a vacuum by sandwiching it with two microdevices each having a thin-film window through which the electron beam can pass.

[0007] Prior Art Documents

[0008] Patent Documents

[0009] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2014-203733

[0010] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2016-072184

[0011] Patent Document 3: Japanese Patent Application Laid-Open No. 2013-535795 Summary of the Invention

[0012] Problems to be Solved by the Invention

[0013] In the sample holder disclosed in Patent Document 1 or Patent Document 2, an aqueous solution (liquid sample) containing a sample or a gel (gel sample) containing a sample is attached to either a first insulating film fixed to a frame portion for the purpose of maintaining strength or the like, or a second insulating film fixed to a frame portion for the purpose of maintaining strength or the like. The two insulating films are opposed to each other and fixed in such a manner as to sandwich the liquid sample or the gel sample, thereby fabricating a sample holder. Alternatively, the first and second insulating films are opposed to each other and fixed in advance, and a mechanism for pouring an aqueous solution into the gap is provided to introduce a liquid sample into the gap between the insulating films.

[0014] As a result of the inventors' examination, it has been found that in the latter method, when observing a gel sample having a relatively high viscosity, it is difficult to introduce the sample between the insulating films, and there is a concern that a load exceeding the withstand voltage is applied to the insulating films, resulting in film rupture. From the viewpoint of high versatility, the former method is more excellent. In addition, hereinafter, unless otherwise particularly distinguished, a liquid sample includes a gel sample.

[0015] In the specimen holders for observation systems disclosed in Patent Documents 1 and 2, when a liquid specimen is sandwiched and fixed with insulating films facing each other, it is important that the liquid specimen leaking between the insulating films does not come into contact with the electrodes located directly below the insulating films. If the leaked liquid specimen comes into contact with the electrodes, a leakage current exceeding the electric signal that provides the contrast of the specimen image will flow, and specimen observation cannot be performed.

[0016] Moreover, in order to ensure the strength of the insulating films, the insulating film windows in the observation target area are mostly rectangular with a side length of 500 μm or less, for example. The observable area is the area where the windows of the first insulating film and the second insulating film overlap, so the alignment of the insulating films with each other is important. In addition, especially in the case of a liquid specimen with a high volatility, it is also important to quickly enclose the specimen.

[0017] Thus, the specimen holder is required to incorporate brittle materials such as insulating films and be able to perform rapid and highly accurate alignment. On the other hand, there is also a requirement to make the structure as simple as possible and achieve the above requirements at low cost. Therefore, the inventors reviewed the structure of the specimen holder that can balance both functional and cost aspects.

[0018] In addition, as a specimen holder having a shape similar to that of the specimen holder of the present invention, there is the specimen holder disclosed in Patent Document 3. However, in the specimen holder of Patent Document 3, two microelectronic devices are pre-stored in the holder body, and after being fixed by the holder cover, a liquid specimen or a gaseous specimen is introduced between the films. This is different from the present invention which assumes that the specimen is introduced before sealing.

[0019] Means for Solving the Problem

[0020] A sample holder according to an embodiment of the present invention is a sample holder for holding a liquid or gel sample, and has: a first component having a lid component and a first chip, the lid component having an opening, being made of metal or having at least the electron beam irradiation surface and the side surface of the opening covered with a metal film, the first chip having a first window with a stacked film formed with a conductive thin film and a first insulating thin film, and being held on the surface of the lid component facing the electron beam irradiation surface such that the conductive thin film is exposed from the opening of the lid component; and a second component having a first seal, a second seal, a base material formed with a first bottom sealing surface for disposing the first seal and a second bottom sealing surface for disposing the second seal, an electrode disposed on the base material, and a second chip, the second chip having a second window formed with a second insulating thin film, and being held on the second bottom sealing surface via the second seal such that the second window faces the electrode, the conductive thin film of the first chip being electrically connected to the metal of the lid component, the first component and the second component being combined, the first seal being flattened between the first bottom sealing surface and the upper sealing surface of the lid component, thereby hermetically holding the internal area from the area outside the first seal.

[0021] The effects of the invention are as follows.

[0022] The sample holder can reliably hold a liquid or gel sample, and improve the qualification rate of observation using a charged particle beam device.

[0023] Other problems and new features will become clear according to the description in this specification and the drawings. Description of the Drawings

[0024] Figure 1A It is a structural diagram of a sample holder (first structural example).

[0025] Figure 1B It is a structural diagram of a sample holder (first structural example).

[0026] Figure 1C It is a structural diagram of a sample holder (first structural example).

[0027] Figure 1D It is a structural diagram of the first component of a sample holder (first structural example).

[0028] Figure 1E It is a structural diagram of the second component of a sample holder (first structural example).

[0029] Figure 1F It is a structural diagram of a sample holder (first structural example).

[0030] Figure 1G It is a structural diagram of a sample holder (first structural example).

[0031] Figure 2A It is a structural diagram of a specimen holder (first structural example).

[0032] Figure 2B It is a structural diagram of a specimen holder (first structural example).

[0033] Figure 2C It is a structural diagram of a specimen holder (first structural example).

[0034] Figure 3 It is a diagram for explaining the first design guideline of the specimen holder.

[0035] Figure 4A It is a structural diagram of a specimen holder (second structural example).

[0036] Figure 4B It is a structural diagram of a specimen holder (second structural example).

[0037] Figure 4C It is a structural diagram of the first component of a specimen holder (second structural example).

[0038] Figure 4D It is a structural diagram of the second component of a specimen holder (second structural example).

[0039] Figure 5A It is a structural diagram of a specimen holder (third structural example).

[0040] Figure 5B It is a structural diagram of a specimen holder (third structural example).

[0041] Figure 5C It is a structural diagram of the first component of a specimen holder (third structural example).

[0042] Figure 5D It is a structural diagram of the second component of a specimen holder (third structural example).

[0043] Figure 5E It is a structural diagram of a specimen holder (third structural example).

[0044] Figure 6A It is a structural diagram of a specimen holder (fourth structural example).

[0045] Figure 6B It is a structural diagram of a specimen holder (fourth structural example).

[0046] Figure 6C It is a structural diagram of the first component of a specimen holder (fourth structural example).

[0047] Figure 7A It is a structural diagram of a specimen holder (fifth structural example).

[0048] Figure 7BIt is a structural diagram of a specimen holder (the fifth structural example).

[0049] Figure 7C It is a structural diagram of the second component of a specimen holder (the fifth structural example).

[0050] Figure 8A It is a structural diagram of a specimen holder (the sixth structural example).

[0051] Figure 8B It is a structural diagram of a specimen holder (the sixth structural example).

[0052] Figure 8C It is a structural diagram of a specimen holder (the sixth structural example).

[0053] Figure 8D It is a structural diagram of a specimen holder (the sixth structural example).

[0054] Figure 8E It is a structural diagram of the first component of a specimen holder (the sixth structural example).

[0055] Figure 8F It is a structural diagram of the second component of a specimen holder (the sixth structural example).

[0056] Figure 9A It is a structural diagram of a specimen holder (the seventh structural example).

[0057] Figure 9B It is a structural diagram of a specimen holder (the seventh structural example).

[0058] Figure 9C It is a structural diagram of a specimen holder (the seventh structural example).

[0059] Figure 9D It is a structural diagram of a specimen holder (the seventh structural example).

[0060] Figure 9E It is a structural diagram of a specimen holder (the seventh structural example).

[0061] Figure 9F It is a structural diagram of the first component of a specimen holder (the seventh structural example).

[0062] Figure 9G It is a structural diagram of the second component of a specimen holder (the seventh structural example).

[0063] Figure 9H It is a structural diagram of a specimen holder (the first modified example of the seventh structural example).

[0064] Figure 9I It is a structural diagram of a specimen holder (the second modified example of the seventh structural example).

[0065] Figure 9JIt is a structural diagram of a specimen holder (second modification example of the seventh structural example).

[0066] Figure 10A It is a structural diagram of a specimen holder (eighth structural example).

[0067] Figure 10B It is a structural diagram of a specimen holder (eighth structural example).

[0068] Figure 11A It is a structural diagram of a specimen holder (ninth structural example).

[0069] Figure 11B It is a structural diagram of a specimen holder (ninth structural example).

[0070] Figure 11C It is a structural diagram of a specimen holder (ninth structural example).

[0071] Figure 12 It is a structural diagram of a specimen holder (tenth structural example).

[0072] Figure 13 It is a structural diagram of a specimen holder (eleventh structural example).

[0073] Figure 14A It is a structural diagram of a specimen holder (twelfth structural example).

[0074] Figure 14B It is a structural diagram of a specimen holder (twelfth structural example).

[0075] Figure 14C It is a structural diagram of the second component of a specimen holder (twelfth structural example).

[0076] Figure 15 It is the shape (schematic diagram) of a seal with a pressure-reducing film.

[0077] Figure 16A It is a structural diagram of a specimen holder (thirteenth structural example).

[0078] Figure 16B It is a structural diagram of a specimen holder (thirteenth structural example).

[0079] Figure 16C It is a structural diagram of the second component of a specimen holder (thirteenth structural example).

[0080] Figure 17 It is the shape (schematic diagram) of a sheet seal with a pressure-reducing film function.

[0081] Figure 18 It is a diagram for explaining the second design guideline of a specimen holder.

[0082] Figure 19 It is a structural diagram of a charged particle beam device. Detailed implementation mode

[0083] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0084] Example 1

[0085] Figures 1A - 1E A structural example (first structural example) of the specimen holder 101 of Example 1 is shown. The specimen holder 101 has a first component 102 and a second component 103. Figure 1A It is a top view of the electron beam irradiation surface 112 of the specimen holder 101 looking down, Figure 1B is Figure 1A A cross-sectional view in the state where the first component 102 and the second component 103 are separated in A-A shown, Figure 1C Similarly, it is a cross-sectional view in the state where the first component 102 and the second component 103 are combined in A-A. The specimen holder 101 is mounted in the specimen chamber of an electron microscope maintained in a vacuum environment in the state where the first component 102 and the second component 103 are combined as shown for observation using the electron microscope. And, Figure 1C is a view of observing the first component 102 from the X direction shown, that is, looking up at the first component 102 from the opposite side of the electron beam irradiation direction, Figure 1D is from Figure 1B is a view of observing the second component 103 from the Y direction shown, that is, looking down at the second component 103 from the electron beam irradiation direction. However, Figure 1E is from Figure 1B is a view of observing the second component 103 from the Y direction shown, that is, looking down at the second component 103 from the electron beam irradiation direction. However, Figure 1E In, in order to show the structure understandably, a part of the second chip 107 is cut away for display, and the actual shape of the second chip 107 is a rectangle shown by a dotted line. Also, the first seal 118 and the second seal 119 are omitted. In addition, in this example, the outer peripheral shapes of the first component 102 and the second component 103 are rectangles, but their shapes are not limited to rectangles, and may be, for example, polygonal shapes or circular shapes. The same applies to the following examples.

[0086] Hereinafter, the specimen holder 101 will be described in detail. The first component 102 of the specimen holder 101 mainly includes a cover component 111 and a first chip 105 held on the opposite side of the electron beam irradiation surface 112 of the cover component 111. The first chip 105 is a cut chip and has a window 123 for electron beam irradiation formed with an insulating film 104 for isolating the external atmosphere. Examples of the insulating film 104 include a silicon nitride film, a silicon oxide film, a carbon film, and a polyimide film. A conductive film 109 is formed on the electron beam irradiation surface side of the first chip 105, and a laminated film of the conductive film 109 and the insulating film 104 is formed on the window 123. Examples of the conductive film 109 include metal films mainly composed of any one of tantalum, tungsten, rhenium, molybdenum, osmium, gold, and platinum.

[0087] The first chip 105 is aligned so that the center of the window 123 for electron beam irradiation coincides with the center of the opening of the cover component 111, and the side with the conductive film 109 formed thereon is fixed to the back surface of the cover component 111 by a fixing seal 110. The fixing seal 110 fixes the first chip 105 and has a vacuum sealing function of sealing the periphery of the liquid specimen 115 from the vacuum atmosphere of the specimen chamber into an atmospheric pressure or quasi-atmospheric pressure state when observed with an electron microscope. For example, a double-sided tape of an Si-based adhesive material can be used as the fixing seal 110. Since the double-sided tape of the Si-based adhesive material has a uniform surface, the vacuum sealing function is excellent.

[0088] The cover component 111 can be a metal or a resin material coated with a metal film on a part or the whole by metal plating or the like. When the resin material is subjected to metal plating, in order to suppress the charging phenomenon caused by electron beam irradiation, it is preferable to perform metal plating at least on the electron beam irradiation surface 112 of the cover component 111 and the inclined surface (side surface of the opening) 113 of the cover component 111. Moreover, an electrical conduction treatment is performed on the electron beam irradiation surface 112 of the cover component 111 and the conductive film 109 of the first chip 105 using a conductive paste 114. However, the method of electrically connecting the electron beam irradiation surface 112 and the conductive film 109 is not limited to the conductive paste. When observed with an electron microscope, a bias voltage is applied to the conductive film 109 of the first chip 105. Therefore, a bias voltage is applied to the electron beam irradiation surface 112 of the cover component 111 by a voltage supply device (not shown). By electrically connecting the electron beam irradiation surface 112 and the conductive film 109, a bias voltage can be applied to the conductive film 109.

[0089] The base material 127 of the second component 103 of the sample holder 101 is formed of an insulator. In addition, metal plating may be applied to the surface of the base material 127 as needed. However, in this case, in a state where the first component 102 and the second component 103 are combined, it is necessary to insulate the electrode 108 of the second component 103 from the electron beam irradiation surface 112 of the first component 102 so that leakage current caused by the bias voltage applied to the conductive film 109 does not flow into the electrode 108 during observation using an electron microscope.

[0090] The second component 103 mainly includes a base material 127, a second chip 107 having a signal transmission window 124 formed with an insulating film 106 for isolating the external atmosphere, an electrode 108 disposed on the base material 127 so as not to contact the second chip 107, a first seal 118, and a second seal 119. When observing using an electron microscope, the electrode 108 is connected to a signal amplification device (not shown). The insulating film 106 can be the film listed as the insulating film 104.

[0091] Alignment guides 116 for the second chip 107 are provided on the base material 127. Specifically, a recess is provided in the central portion of the base material 127, and the side wall of the recess functions as the alignment guide 116. The second chip 107 is inserted into the alignment guide 116 provided on the base material 127 and placed in a state of contacting the second seal 119. The alignment is performed in advance so that the center of the electrode 108 coincides with the center of the alignment guide 116. By inserting the second chip 107 into the alignment guide 116, the center of the signal transmission window 124 of the second chip 107 is aligned with the center of the alignment guide 116. With such a structure, the center of the signal transmission window 124 is aligned with the center of the electrode 108. As Figure 1C shown, the first seal 118 and the second seal 119 are deformed in a flattened manner by pressing the first component 102 and the second component 103 together, thereby sealing two surfaces (upper and lower surfaces) or three surfaces (upper and lower surfaces and side surface) in contact with the first component 102 and the second component 103.

[0092] Specifically, the first seal 118 is compressed at least between the first bottom sealing surface 203 formed on the base material 127 and the upper sealing surface 205 of the lid member 111, isolating the first space 120 capable of accommodating the second chip 107 from the external atmosphere. The second seal 119 is compressed at least between the second bottom sealing surface 200 formed on the base material 127 and the bottom surface of the second chip 107, isolating the second space 121 where the front end portion of the disposed electrode 108 is located from the surrounding first space 120. The second space 121 is a space formed by being surrounded by the bottom surface of the second chip 107, the second bottom sealing surface 200 of the base material 127, and the second seal 119.

[0093] In Figures 1A - 1E the sample holder 101 shown, an O-ring is used as the first seal 118 and the second seal 119. In contrast, Figures 1F - 1G an example of a sample holder is shown in which an O-ring is used as the first seal 118 and a double-sided tape is used as the second seal 119. The top view of the electron beam irradiation surface 112 of the sample holder 101 is the same as Figure 1A that of Figures 1F - 1G and is Figure 1A the cross-sectional view taken along A-A shown.

[0094] In Figures 1F - 1G the sample holder 101 shown, as the second seal 119, a double-sided tape can be used, which has a structure in which an Si rubber sheet 140 is clamped by Si-based adhesive sheets 150 having uniform surfaces on both sides. In this case, by pressing the first member 102 and the second member 103 together, the Si rubber sheet 140 is compressed as Figure 1G shown, thereby isolating the second space 121 where the electrode 108 is disposed from the first space 120. In the embodiments described below, unless otherwise specified, the second seal 119 can be an O-ring or a double-sided tape. By using a double-sided tape, the second chip 107 can be fixed to the base material 127, and thus there is an advantage that the risk of the second chip 107 falling off from the base material 127 can be reduced when an impact is erroneously applied to the second member 103 or the like.

[0095] Next, the process from placing the sample on the sample holder 101 until it becomes a state where it can be observed using an electron microscope will be described.

[0096] First, Figure 1BThe state shown. No structure of the first component 102 is in contact with any structure of the second component 103. In this state, for example, a micropipette is used to deposit the liquid sample 115 onto the surface of the insulating film 106 of the second chip 107 placed inside the guide 116 of the base material 127. Alternatively, the surface to which the liquid sample 115 is deposited may be the insulating film 104 of the first chip 105 of the first component 102. Subsequently, the first component 102 is brought closer to the second component 103, either manually or through automated operations such as robotics.

[0097] Figure 2A The state in which the insulating film 104 of the first component 102 is in contact with the liquid sample 115 is shown. In this state, the first chip 105 begins to be embedded in the guide 116 of the second component 103, and the first chip 105 and the second chip 107 are aligned. The first chip 105 is aligned by being embedded in the guide 116 so that the center of the cover component 111, the center of the electron beam irradiation window 123 of the first chip 105, the center of the signal transmission window 124 of the second chip 107, and the center of the electrode 108 are aligned. In this state, the first seal 118 is not in contact with the first component 102, and the first seal 118 is not deformed. On the other hand, the second seal 119 begins to deform in a flattened manner due to the downward force applied by the liquid sample 115. In addition, Figure 2C This is an example of a case where the amount of liquid sample 115 is extremely small. In this example, when the first chip 105 begins to be embedded in the guide 116 of the second component 103 and the first chip 105 and the second chip 107 are aligned, the liquid sample 115 does not contact the insulating film 104 of the first chip 105, and the force pressing down the second chip 107 does not work. Figure 2C In this case, when the first chip 105 and the second chip 107 are aligned, neither the first sealing member 118 nor the second sealing member 119 begins to deform.

[0098] Thus, the guide 116 is provided as a guide for aligning the second chip 107 relative to the base material 127, but it also functions as a guide for aligning the first chip 105 and the second chip 107. In view of the function used in the alignment of the opposing chips, the guide 116 is referred to as a guide for opposing chips. In addition, it does not matter whether the guide for opposing chips is a guide for the chip arranged on its own component (cover component or base material), but when the first chip 105 and the second chip 107 are congruent, the guide for opposing chips also serves as a guide for the chip arranged on its own component, thereby being able to obtain higher alignment accuracy with a simple structure.

[0099] In addition, as described above, at the moment when the alignment of the first chip 105 and the second chip 107 is performed using the guide member 116, it is important that the first seal 118 is not deformed (this is referred to as "key point 1"). If the first seal 118 starts to deform at this time, due to the resilience of the first seal 118 attempting to return to its original shape, a force will act to press the first component 102 back toward the electron beam irradiation surface 112 side. On the other hand, if the cover member 111 is opaque, it is impossible to visually confirm whether the first chip 105 is inserted into the guide member 116. Therefore, it is determined by the presence or absence of resistance generated by the interference between the first chip 105 and the guide member 116 when the first component 102 is pressed into the second component 103. Therefore, if the cover member 111 is in a state of bearing the resilience of the first seal 118 during the alignment stage, it is difficult to identify the presence or absence of resistance generated by interference. If the first component 102 is pressed in a state where the first chip 105 interferes with the guide member 116, the first chip 105 may be damaged.

[0100] Also, it is important that the second seal 119 is flattened earlier than the first seal 118 (this is referred to as "key point 2"). Thereby, even if the remaining liquid-like specimen leaks into the first space 120 formed by the concave portion of the base material 127 forming the guide member 116 and the first component 102, it will not invade the second space 121 shielded by the second seal 119. As a result, it is possible to prevent the liquid-like specimen from coming into contact with the electrode 108.

[0101] Therefore, the timing at which the second seal 119 starts to be flattened is preferably as early as possible. If the second seal 119 starts to be flattened during the alignment stage, the cover member 111 bears the resilience of the second seal 119. However, the resilience of the second seal 119 is smaller than that of the first seal 118. In this example, as Figure 2A shown, in a state where the risk of leakage of the liquid-like specimen is high, it is assumed that the second seal 119 starts to be flattened during the alignment stage. As Figure 2C shown, in a state where the risk of leakage of the liquid-like specimen is low, it is assumed that the second seal 119 starts to be flattened after alignment, thereby effectively suppressing the occurrence of adverse conditions.

[0102] In a state where the alignment of the first chip 105 and the second chip 107 has been performed using the guide member 116 of the second component 103, for example, the first component 102 is pressed against the second component 103 using a plurality of threaded members 117 (refer to Figure 1A ).

[0103] The first component 102 is provided with a through hole 128 (refer to Figure 1D ) for the threaded member 117 to pass through, and the second component 103 is provided with a threaded hole 129 (refer to Figure 1E)。In order to absorb the errors caused by the manufacturing accuracy of the guide member 116 and the alignment accuracy of the first chip 105 relative to the first component 102, the diameter of the through-hole 128 is set to be slightly larger than the nominal diameter of the threaded member. In this example, the first chip 105 and the second chip 107 are cut into rectangles of the same size with a side length of about several millimeters, and the guide member 116 is made slightly larger than the first and second chips so that the two chips can be inserted with a tolerance of about 100 μm or less. And, in this example, as Figure 1E shown, the guide member 116 has a circular chip recess 130 at the corner portion. The cut chips sometimes have residues at the corners. Even in such a case, by having the chip recess 130, the chips can be easily inserted into the guide member 116.

[0104] Figure 2B is the state after being further pressed down by tightening the threaded member etc. from the Figure 2A state, and is the state before the first seal 118 starts to deform due to the first component 102. In this state, according to the amount of the dropped liquid sample 115, sample leakage occurs from the side walls of the first and second chips. In this state, the second seal is also in the middle of the process of being flattened, isolating the second space 121 in which the electrodes 108 are arranged from the sample 122 leaking from the chip side walls.

[0105] Figure 1C is the state in which the first component 102 and the second component 103 are finally combined and fixed and can be observed using an electron microscope. As a result of the pressing down, in the state where there is a flattening margin remaining in both the first seal 118 and the second seal 119, the first component 102 and the second component 103 stop due to the contact of the structures other than the two seals with each other. In this case, the pressing down stops because the fixed seal 110 of the first component 102 contacts the base material 127 of the second component 103. In addition, when the fixed seal 110 has a flattening margin, the tightening strength of the threaded member 117 for fixing the first component 102 and the second component 103 can also be managed using a torque wrench etc.

[0106] In this state, the first seal 118 hermetically isolates the first space 120 from the external environment maintained at a high vacuum atmosphere for electron beam irradiation. On the other hand, the second seal 119 hermetically isolates the second space 121 in which the electrodes 108 are arranged from the surrounding first space 120. And, the second seal 119 also isolates the second space 121 from the sample 122 leaking from the side walls of the first chip 105 and the second chip 107. The second chip 107 is fixed in the state of being sandwiched with the liquid sample 115 and pressed against the first chip 105 by the resilience of the deformed second seal 119 that wants to return to its original shape.

[0107] Use Figure 3 , showing the first design guideline of the specimen holder. Figure 3 Shows the following state: In the state without a specimen, the insulating film 104 of the first chip 105 is in surface contact with the insulating film 106 of the second chip 107. Use the following values defined in this state to determine the shape. In addition, regarding the dimensions and specifications of each component such as chips and various seals, and the points that need to be designed considering the tolerances during manufacturing, those skilled in the art can easily infer. In the following description, the second bottom sealing surface 200 is used as the reference position (0), the distance from here to the upper position is set as a positive distance, and the distance from here to the lower position is set as a negative distance.

[0108] The depth a of the guide 116 is defined by the distance from the second bottom sealing surface 200 to the front end of the guide 116 (the upper surface of the base material 127). The depth a of the guide 116 satisfies the relationship of (Equation 1).

[0109] The depth a of the guide > the thickness of the second seal 119 + the thickness of the second chip 107... (Equation 1)

[0110] In addition, the thickness of the second seal 119 is its diameter in the case of an O-ring and its thickness in the case of a double-sided tape. By satisfying (Equation 1), when the insulating films of the first chip 105 and the second chip 107 are in contact with each other as Figure 3 shown, it is ensured that the first chip 105 is in a state of being embedded in the guide 116. That is, it is ensured that the contact surface between the insulating film 104 and the insulating film 106 is located between the base material 127 provided with the guide for the opposing chip and the front end of the guide for the opposing chip.

[0111] And, the first sealing surface distance b defined as the distance from the upper sealing surface 205 of the cover member 111 to the second bottom sealing surface 200, and the second sealing surface distance c defined as the distance from the first bottom sealing surface 203 to the second bottom sealing surface 200 satisfy the relationship of (Equation 2).

[0112] ABS (first sealing surface distance b - second sealing surface distance c) > the thickness of the first seal 118... (Equation 2)

[0113] In addition, the thickness of the first seal 118 is its diameter in the case of an O-ring.

[0114] In the first structural example, by satisfying both (Equation 1) and (Equation 2), it is possible to satisfy both the condition (Key Point 1) of "at the moment when the alignment of the first chip 105 and the second chip 107 starts, the first seal 118 is not deformed" and the condition (Key Point 2) of "the second seal 119 is flattened before the first seal 118".

[0115] However, what needs to satisfy (Equation 1) is the structure in which the alignment of the first chip 105 and the second chip 107 is performed by using the opposing chip guide 116 provided on the second component 103 in the first structural example. That is, if the method of aligning the first chip 105 and the second chip 107 is different, (Equation 1) is changed accordingly. For example, it is also considered to provide the opposing chip guide on the first component (such as a cover component), but in this case, instead of (Equation 1), in the state without a specimen, the insulating film 104 of the first chip 105 is in surface contact with the insulating film 106 of the second chip 107, and in this state, it is required that the height of the opposing chip guide from the surface of the cover component 111 that fixes the first chip 105 is greater than the sum of the thickness of the fixed seal 110 and the thickness of the first chip 105. When this condition is satisfied, it is ensured that the contact surface of the insulating film 104 and the insulating film 106 is located between the cover component 111 provided with the opposing chip guide and the front end of the opposing chip guide.

[0116] Figures 4A - 4D Shows a structural example (second structural example) of the specimen holder 301 of Example 1. The top view is the same as Figure 1A the same, Figures 4A - 4B respectively Figure 1A the cross-sectional view taken along A-A shown.

[0117] In the second structural example, the first component 102 is provided with a first chip guide 402 for embedding the first chip 105. Thus, the first chip 105 is aligned in such a manner that the center of the window 123 for electron beam irradiation is located at the center of the opening of the cover component 111. It is easy to perform this alignment by using the chip guide 402. The first chip 105 is fixed to the cover component 111 by the fixed seal 110. As Figure 4C shown, similar to the guide 116 in the first structural example, a circular chip retreat portion 130 is provided in the guide 402.

[0118] And, in the second structural example, a liquid accumulation portion 302 for accumulating the remaining specimen 122 leaking from the side wall between the chips is provided. With such a structure, the risk of the leaked specimen 122 coming into contact with the electrode 108 can be further reduced. In the first structural example, the guide 116 surrounds the entire circumference of the chip by forming a columnar recess in the base material 127. In contrast, in the second structural example, as Figure 4A and Figure 4DAs shown, a concave portion including a liquid accumulation portion 302 is provided in the central portion of the base material 127, and plate-shaped guide members 116 are provided in the concave portion so as to face the four sides of the chip respectively. By adopting such a shape, it has the advantage of facilitating the processing of the base material 127.

[0119] In the second structural example, similar to the first structural example, during the downward pressing process, with the state that there is a flattened margin remaining in both the first seal 118 and the second seal 119, the first component 102 and the second component 103 come into contact with structures other than the two seals and stop. In this example, the downward pressing stops when the cover member 111 of the first component 102 comes into contact with the base material 127 of the second component 103. Therefore, if the cover member 111 and the base material 127 are made of materials with appropriate strength, there is no need to manage the force for fixing the cover member 111 of the first component 102 and the base material 127 of the second component 103.

[0120] In Figures 4A - 4D the second structural example shown, by satisfying (Equation 1) and (Equation 2) shown in the first structural example, the key points 1 and 2 when combining the first component 102 and the second component 103 can be satisfied.

[0121] Figures 5A - 5E A structural example (third structural example) of the specimen holder 401 of Example 1 is shown. The top view is the same as Figure 1A the same, Figures 5A - 5B 、 Figure 5E respectively are Figure 1A the cross-sectional views taken along A-A shown.

[0122] In the third structural example, similar to the second structural example, the first component 102 is provided with a first chip guide 402 for embedding the first chip 105, and the first chip 105 is aligned so that the center of the window 123 for electron beam irradiation is located at the center of the opening of the cover member 111. The first chip 105 is fixed to the cover member 111 by a fixed seal 110. On the other hand, the second component 103 is provided with a second chip guide 403 for embedding the second chip 107. Thus, the second chip 107 is aligned so that the center of the window 124 for signal transmission coincides with the center of the electrode 108. In this example, the first chip guide 402 is Figure 5C the side wall of the concave portion provided in the central portion of the cover member 111 shown, and the second chip guide 403 is a plate-shaped guide member provided in the concave portion including the liquid accumulation portion 302 provided in the central portion of the base material 127 as shown in Figure 5D shown.

[0123] In the third structural example, the first component 102 and the second component 103 are provided with guides for aligning the centers of the opening of the lid component 111 of the first component 102 and the electrode 108 of the second component 103, respectively. Specifically, the first component 102 is provided with a guide 404 for the second component, and the second component 103 is provided with a guide 405 for the first component. In this example, the guide 404 for the second component is Figure 5C the plate-shaped guide shown, and the guide 405 for the first component is the side wall of the recess including the liquid accumulation part 302 provided at the central part of the base material 127 as shown in Figure 5D .

[0124] Figure 5B is a state where the first component 102 is pressed down, the first component 102 and the second component 103 are combined and fixed, and observation can be performed using an electron microscope. By inserting the guide 404 for the second component into the guide 405 for the first component, alignment is performed in such a way that the centers of the window 123 for electron beam irradiation, the window 124 for signal transmission, and the electrode 108 coincide with the center of the opening of the lid component 111.

[0125] Similar to the second structural example, in the third structural example, during the pressing process, with a state where there is a flattened margin remaining in both the first seal 118 and the second seal 119, the first component 102 and the second component 103 stop when the lid component 111 of the first component 102 contacts the base material 127 of the second component 103.

[0126] In the third structural example, as shown in Figure 5E , if it is designed such that the guide 404 for the second component contacts the guide 405 for the first component before the insulating films of the first chip 105 and the second chip 107 come into contact with each other, alignment of the first chip 105 and the second chip 107 can be performed. That is, the guide 405 for the first component and the guide 404 for the second component have a height such that when the front ends of the guide 405 for the first component and the guide 404 for the second component come into contact, the insulating film 104 of the first chip 105 and the insulating film 106 of the second chip 107 do not come into contact. In this structural example, the shapes of the lid component 111 and the base material 127 become complex, but the risk of damaging the chips when combining the first component 102 and the second component 103 can be reduced.

[0127] In the third structural example, as shown in Figure 5BAs shown, in a state where the first component 102 and the second component 103 are combined and fixed and can be observed using an electron microscope, it is further preferable that the front end of the second-chip guide 403 embedded in the second chip 107 is positioned below the upper surface (insulating film 106) of the second chip 107. This is because if the front end of the second-chip guide 403 is positioned above the upper surface (insulating film 106) of the second chip 107, during the process of pressing down the first component 102, when there is a slight positional deviation caused by manufacturing errors or the like between the first chip 105 and the second chip 107, the second-chip guide 403 interferes with the lower surface (insulating film 104) of the first chip 105, and there is a concern that the first chip 105 may be damaged. For the same reason, it is preferable that the lower end of the first-chip guide 402 embedded in the first chip 105 (in this case, equal to the lower surface of the cover member 111) is positioned above the lower surface (insulating film 104) of the first chip 105.

[0128] In addition, the shapes of the first-chip guide 402, the second-chip guide 403, the second-component guide 404, and the first-component guide 405 are not limited to Figures 5A - 5E the shapes shown, and any shape can be used as long as the above-mentioned functions can be satisfied.

[0129] Figures 6A - 6C The structural example (fourth structural example) of the specimen holder 501 of the first embodiment is shown. The top view is the same as Figure 1A except for the method of electrical conduction between the conductive film 109 of the first chip 105 and the electron beam irradiation surface 112 of the cover member 111 described below. Figures 6A - 6B They are respectively cross-sectional views of the parts corresponding to A-A shown in Figure 1A . Figure 6C It is a view of the first component 102 observed from the X direction shown in Figure 6A , that is, a view of the first component 102 looking up from the opposite side of the electron beam irradiation direction.

[0130] In the fourth structural example, the first chip 105 is larger than the second chip 107. The first component 102 includes a first-chip guide 402 embedded in the first chip 105, and the first chip 105 is aligned such that the center of the window 123 for electron beam irradiation is located at the center of the opening of the cover member 111. The first chip 105 is fixed to the cover member 111 around it by an adhesive material 510. The adhesive material 510 is insulating and also serves as a vacuum seal. As Figure 6AAs shown, with the conductive film 109 of the first chip 105 in contact with the bottom surface of the concave portion forming the guide member 402 for the first chip, the first chip 105 is fixed to the lid member 111, so that the conductive film 109 is electrically connected to the electron beam irradiation surface 112. Thus, no conductive paste is required.

[0131] The second member 103 is the same as the third structural example. Since the adhesive material 510 also serves as a vacuum seal, the sealing function can be improved by thickly stacking the adhesive material 510. On the other hand, in the case of contact with the structure of the second member 103, there is also a concern about adverse conditions caused by the clamping of the liquid specimen 115 by the first chip 105 and the second chip 107. Therefore, as Figure 6B shown, in the state where the first member 102 and the second member 103 are combined and fixed and can be observed with an electron microscope, the adhesive material 510 does not contact the second member 103.

[0132] Figures 7A - 7C Shows a structural example (fifth structural example) of the specimen holder 601 of Example 1. The top view is the same as Figure 1A the same, Figures 7A - 7B respectively are Figure 1A the cross-sectional views taken along A-A shown. Figure 7C is from Figure 7A the view of observing the second member 103 in the Y direction shown, that is, looking down on the second member 103 from the electron beam irradiation direction.

[0133] In the fifth structural example, the second chip 107 is larger than the first chip 105. Along with this, as Figure 7C shown, the guide member 403 for the second chip also becomes larger. Other than this, it is the same as the third structural example. By making the second chip 107 larger than the first chip 105, the specimen 122 leaking from the side wall of the first chip 105 can be held on the surface of the second chip 107 in an area that does not overlap with the first chip 105. Therefore, the risk of the specimen 122 invading the second space 121 and contacting the electrode 108 can be reduced.

[0134] Figures 8A - 8F Shows a structural example (sixth structural example) of the specimen holder 701 of Example 1. The device for fixing the first member 102 and the second member 103 in the sixth structural example is different from the structural examples described above. The top view is equivalent to the view obtained by removing the threaded member 117 from the top view shown in Figure 1A shown. Figures 8A - 8D respectively are the cross-sectional views of the portions corresponding to A-A shown in Figure 1A shown. Figure 8E is from Figure 8A the view of observing the first member 102 in the X direction shown, that is, looking up at the first member 102 from the opposite side of the electron beam irradiation direction, Figure 8Fis from Figure 8A A view of the second component 103 as observed in the Y direction shown, that is, a view of the second component 103 looking down from the electron beam irradiation direction.

[0135] In this way, the first component 102 and the second component 103 do not have the structure required for fixing using threaded members. Instead of threaded members, fixing hook portions 702 are provided on the four sides of the first component 102, and warping portions 703 for hook portions corresponding thereto are provided on the four sides of the second component 103. As Figure 8D shown, by engaging the fixing hook portions 702 with the warping portions 703 for hook portions, the first component 102 and the second component 103 are fixed. The fixing hook portions 702 are provided at the front ends of first hook portion guide members 704 extending in a direction perpendicular to the electron beam irradiation surface 112 of the cover member 111, and second hook portion guide members 705 are provided corresponding to the first hook portion guide members 704 on the four sides of the base material 127.

[0136] Use Figures 8A - 8D To describe the process from when the specimen is placed on the specimen holder 701 until it becomes a state where it can be observed using an electron microscope.

[0137] Figure 8A is a state where the first hook portion guide member 704 of the first component 102 starts to be inserted into the second hook portion guide member 705. From this state, by manual or automatic operation such as a robot, the first component 102 is pressed down to approach the second component 103. In a situation where the first hook portion guide member 704 is inserted into the second hook portion guide member 705, while pressing down the first component 102, the first chip 105 is aligned with the guide member 116 provided on the second component 103.

[0138] Figure 8BThis is the state in which the insulating film 104 of the first chip 105 is in contact with the liquid sample 115. In this state, the first chip 105 starts to be inserted into the guide member 116, and alignment between the first chip 105 and the second chip 107 is performed. At this moment, in order to enable precise alignment, it is preferable that the fitting of the guide member 704 for the first hook portion and the guide member 705 for the second hook portion has a slightly larger tolerance than the fitting of the first chip 105 and the guide member 116. Thereby, alignment is performed such that the center of the opening of the lid member 111, the center of the window 123 for electron beam irradiation, the center of the window 124 for signal transmission, and the center of the electrode 108 are aligned. At this time, the first seal 118 does not contact the first member 102, and the first seal 118 is not deformed. On the other hand, the second seal 119, which is subjected to a downward pressing force via the sample, starts to deform in a flattened manner. And the fixing hook portion 702 of the first member 102 interferes with the hook portion warping portion 703 of the second member 103, and starts to warp in an outward direction perpendicular to the outer peripheral surface.

[0139] Figure 8C It is from Figure 8B This is the state before further pressing down the first member 102 from the state where the first seal 118 is about to start deforming due to the first member 102. In this state, depending on the amount of the dropped liquid sample 115, sample leakage occurs from the side walls of the first and second chips. In this state, the second seal is also in the middle of the flattening process, isolating the second space 121 in which the electrode 108 is disposed from the sample 122 leaking from the chip side walls. At this time, the fixing hook portion 702 of the first member 102 is about to cross over the hook portion warping portion 703 of the second member 103.

[0140] Figure 8D This is the state in which the first member 102 and the second member 103 are combined and fixed and can be observed using an electron microscope. At this time, the fixing hook portion 702 of the first member 102 crosses over the hook portion warping portion 703 of the second member 103, and the fixing hook portion 702 and the hook portion warping portion 703 are fixed in a contacting state. The first member 102 is fixed in a state where the restoring force of the deformed first seal 118 and the deformed second seal 119 that want to return to their original shapes balances the force of the hook portion warping portion 703 that holds the fixing hook portion 702.

[0141] In this state, the first seal 118 hermetically isolates the first space 120 from the external environment which is maintained at a high vacuum atmosphere for electron beam irradiation. On the other hand, the second seal 119 hermetically isolates the second space 121 in which the electrode 108 is disposed from the surrounding first space. Also, the second seal 119 isolates the second space 121 from the specimen 122 leaking from the side walls of the first chip 105 and the second chip 107. The second chip 107 is fixed in a state where the liquid specimen 115 is sandwiched and pressed against the first chip 105 due to the resilience of the deformed second seal 119 attempting to return to its original shape.

[0142] In this structural example, there is no need for screw fixation when fixing the specimen holder, and the specimen holder can be prepared quickly and easily.

[0143] Since the first component 102 of the specimen holder 701 has the deformed first hook-shaped part guide 704, the material of the cover component 111 is preferably a material obtained by metal plating the relatively soft resin as described above.

[0144] In addition, it can also be configured such that, contrary to the component having the fixing hook-shaped part and the warping part for the hook-shaped part, the first component 102 has the warping part for the hook-shaped part and the second component 103 has the fixing hook-shaped part. In this case, since there is no deformed part in the first component 102, the cover component 111 can be made of a metal material.

[0145] In addition, as a sixth structural example, an example in which the fixing method using the hook-shaped part is applied to the specimen holder corresponding to the first structural example is shown, but it can also be applied to other structural examples or their modified examples described above.

[0146] Figures 9A - 9G A structural example (seventh structural example) of the specimen holder 801 of Example 1 is shown. Figure 9A It is a top view of the electron beam irradiation surface 112 of the specimen holder 801, Figures 9B - 9E In the figure above, the sectional views taken along A-A respectively shown Figure 1A are shown, and in the figure below, the top view of B-B in this sectional view is shown. Figure 9F It is a view Figure 9B observing the first component 102 from the X direction shown, that is, looking up at the first component 102 from the side opposite to the electron beam irradiation direction, Figure 9G It is a view Figure 9B observing the second component 103 from the Y direction shown, that is, looking down at the second component 103 from the electron beam irradiation direction.

[0147] As Figure 9AAs shown, the outer peripheral shape of the specimen holder 801 is circular. In the seventh structural example, the first component 102 is fixed to the second component 103 by being screwed into the second component 103.

[0148] Figures 9B - 9E The process of screwing and fixing the first component 102 to the second component 103 is shown. In addition, in the top view of the figure below, it is shown that the first component 102 does not rotate relative to the paper surface while the second component 103 rotates. As will be described below, the second chip 107 rotates together with the first chip 105 relative to the base material 127. Therefore, the second chip 107 is not fixed to the base material 127. Therefore, as the second seal 119, an O-ring is preferably used.

[0149] The specimen holder 801 has the shape of a tea canister, the base material 127 of the second component 103 has a cylindrical shape, and the lid member 111 of the first component 102 has a peripheral portion extending in a direction perpendicular to the electron beam irradiation surface.

[0150] On the inner wall of the peripheral portion of the lid member 111 in contact with the outer peripheral portion of the base material 127, a thread structure 810 is provided. The first chip 105 is fixed to the back surface of the lid member 111 by the fixing seal 110. On the back surface of the lid member 111 holding the first chip 105, a first-chip guide member 402 for fitting the first chip 105 is provided. Thereby, the first chip 105 is aligned such that the center of the window 123 for electron beam irradiation is located at the center of the opening of the lid member 111. And as Figure 9F shown, four guide members (opposing-chip guide members) 116 used in the alignment of the first chip 105 and the second chip 107 are provided on the back surface of the lid member 111.

[0151] In addition, instead of providing the first-chip guide member 402 on the lid member 111, the four guide members 116 can be used to align the center of the opening of the lid member 111 with the center of the window 123 for electron beam irradiation.

[0152] On the other hand, the base material 127 of the second component 103 has a cylindrical shape and has a thread structure 811 that meshes with the thread structure 810 of the first component 102. By meshing the above thread structures, the first component 102 is screwed into the second component 103 to fix the two.

[0153] As Figure 9GAs shown, the second component 103 includes a second chip guide 403 for embedding the second chip 107. The second chip 107 is placed on the second seal 119 placed on the second bottom sealing surface 200. In this state, the second chip 107 is aligned such that the center of the signal transmission window 124 coincides with the center of the electrode 108. In addition, the second chip guide 403 is the side wall of a recess including a liquid accumulation portion 302 provided in the central portion of the base material 127.

[0154] The process of placing the specimen on the specimen holder 801 until it reaches a state where it can be observed with an electron microscope will be described. First, when the second chip 107 is placed in the second chip guide 403, it is placed in a state where it is rotated to a position where it cannot be further rotated in the counterclockwise direction shown. Figure 9G As shown.

[0155] In Figure 9B the state shown, no structure of the first component 102 contacts the structure of the second component 103. From this state, the first component 102 is brought closer to the second component 103 by manual or automatic operation such as by a robot.

[0156] Figure 9C A state where the insulating film 104 of the first chip 105 is in contact with the liquid specimen 115 is shown. This is a state where the first thread structure 810 is not engaged with the second thread structure 811 and the first component 102 is disposed on the second component 103. On the other hand, as shown in the top view of the lower figure in Figure 9C , the second chip 107 starts to be embedded in the guide 116 provided in the first component 102, and the first chip 105 and the second chip 107 are aligned. Thereby, alignment is performed such that the center of the opening of the lid member 111, the center of the electron beam irradiation window 123, the center of the signal transmission window 124, and the center of the electrode 108 coincide. And at this stage, the first seal 118 does not contact the first component 102, and the first seal 118 is not deformed. On the other hand, the second seal 119, which is subjected to a downward pressing force via the liquid specimen 115, starts to be deformed in a flattened manner.

[0157] Figure 9D A state where the first thread structure 810 contacts the second thread structure 811 and the first component 102 starts to be screwed into the second component 103 is shown. It is also a state before the first seal 118 starts to be deformed due to the first component 102. At this time, depending on the amount of the liquid specimen 115 dropped, specimen leakage occurs from the side walls of the first and second chips. Since the second seal 119 is in the middle of the process of being flattened, the electrode 108 is isolated from the specimen 122 leaking from the chip side wall.

[0158] As inFigure 9D As shown in the top view of the figure below, with the second chip 107 in a state where it is aligned with the first chip 105 according to the guide member 116, the second chip 107 slides on top of the second seal 119 and rotates together with the first chip 105.

[0159] Figure 9E It is a state where the first component 102 and the second component 103 are combined and fixed, and can be observed using an electron microscope. In this state, the guide member 116 of the first component 102 and the guide member 403 for the second chip of the second component 103 are fixed in contact so as not to rotate further. In this way, in the seventh structural example, a locking mechanism that restricts the amount of rotation of the base material 127 relative to the cover member 111 is provided to suppress the pressing amount of the first chip 105 against the second chip 107 from being excessive or too little. In this case, the locking mechanism is realized by the guide member 116 and the guide member 403 for the second chip, but it can also be provided independently of them. For example, a groove is provided on the outer periphery of the upper end of the base material 127, and a rotation stopper is provided at one part thereof. On the other hand, the cover member 111 is provided with a convex portion that is inserted into the groove when the first component 102 and the second component 103 are combined. The first component 102 is screwed into the second component 103, and the convex portion moves in the groove and stops when it hits the rotation stopper, completing the screwing.

[0160] In the seventh structural example, the first component 102 is fixed in a state where the resilience of the deformed first seal 118 attempting to return to its original shape is balanced with the holding force exerted by the frictional force acting between the thread structure 810 of the first component and the thread structure 811 of the second component.

[0161] In addition, the fixing method based on screwing in this structural example can also make the second chip 107 larger than the first chip 105 as in the fifth structural example, for example. In this case, it is only necessary to change the shapes of the four guide members 116 and the guide member 403 for the second chip corresponding to the size of the second chip 107.

[0162] In the seventh structural example, since the first chip 105 and the second chip 107 rotate simultaneously during screwing, there are the following two advantages. First, by the simultaneous rotation of the two chips, the liquid sample sandwiched between the two chips will not rub against each other between the films, reducing the risk of film breakage. Second, by fixing the overlapping situation of the two chips, the field of view determined by the overlap of the window 123 of the first chip 105 and the window 124 of the second chip 107 can be ensured without being affected by the introduction operation of the liquid sample into the sample holder 801. Hereinafter, a modified example of the seventh structural example is shown.

[0163] Figure 9HA first modification example is shown. In the first modification example, the first component 102 includes a guide 404 for the second component, and the first chip 105 is fixed to the cover component 111. The first chip 105 is fixed such that the center of the electron beam irradiation window 123 coincides with the central axis of the guide 404 for the second component. Further, the second component 103 includes a guide 403 for the second chip and a guide 405 for the first component. The central axes of the guide 403 for the second chip and the guide 405 for the first component are arranged to coincide with the central axis of the electrode 108. When the second chip 107 is placed in alignment with the guide 403 for the second chip, the center of the signal transmission window 124 coincides with the central axis of the electrode 108. As Figure 9H shown, each of the guides 403, 404, and 405 is circular. In particular, in a state where the first component 102 and the second component 103 are combined, the guides 403, 404, and 405 are concentric.

[0164] The first chip 105 and the second chip 107 have congruent square shapes, and the diameter of the guide 403 for the second chip is processed to be slightly larger than the length of the diagonal of the chip. To fix the first component 102 to the second component 103, first, the first component 102 is placed on the second component 103. In this example, the front end of the guide 405 for the first component of the second component 103 is located above the front end of the guide 404 for the second component. However, when the front end of the guide 405 for the first component comes into contact with the front end of the guide 404 for the second component, the insulating film 104 of the first chip 105 does not contact the insulating film 106 of the second chip 107 (the positional relationship between the front end portions of the above guides and the insulating films is the same as Figure 5E . By the above steps, alignment is performed such that the center of the window 123 of the first chip 105 coincides with the center of the window 124 of the second chip 107. Thereafter, the threaded structure 810 of the first component 102 is engaged with the threaded structure 811 of the second component 103 and rotated to be fixed.

[0165] In this modification example, the structures such as the guides formed on the cover component 111 and the base material 127 can be made circular, which has the advantage of cost reduction. On the other hand, when the first component 102 is screwed and fixed, the first chip 105 rotates relative to the second chip 107 while being fixed, thereby increasing the risk of film breakage. Also, depending on the overlapping situation of the first chip 105 and the second chip 107 during fixing, it may not be possible to obtain the maximum field of view. For example, in Figure 9H the top view (lower figure) shows an example where the phases of the first chip 105 and the second chip 107 are shifted by 45°. However, since this state is the minimum field of view of the specimen holder 801b, it is only necessary to ensure the required field of view in this state.

[0166] In Figures 9I - 9J a second modification is shown. Figure 9I The state in which the components constituting the sample holder 801c are separated is shown, Figure 9J and the state in which the components are combined is shown. In the second modification, while maintaining the structure of the guide that can reduce the cost of the first modification, the risk of film breakage can be reduced. In the second modification, in order to fix the first component 102 to the second component 103, a threaded cap 125 is used. The threaded cap 125 has the shape of a tea cylinder having an opening 125a for allowing an electron beam to pass through, has a peripheral portion extending in a direction perpendicular to the bottom surface provided with the opening 125a, and has a threaded structure 810 on the inner wall of the peripheral portion. Further, a disk-shaped washer 126 is provided between the threaded cap 125 and the first component 102.

[0167] The outer peripheral portion of the first component 102 serves as a guide 404 for the second component, and the first chip 105 is fixed to the cover member 111. The first chip 105 is fixed such that the center of the electron beam irradiation window 123 coincides with the central axis of the guide 404 for the second component. Further, the second component 103 includes a guide 403 for the second chip and a guide 405 for the first component. The central axes of the guide 403 for the second chip and the guide 405 for the first component are arranged to coincide with the central axis of the electrode 108, and when the second chip 107 is placed in alignment with the guide 403 for the second chip, the central axis of the signal transmission window 124 coincides with the central axis of the electrode 108. As Figure 9I shown, each of the guides 403, 404, and 405 is circular, and in particular, in a state where the first component 102 and the second component 103 are combined, the guides 403, 404, and 405 are concentric circles.

[0168] The first chip 105 and the second chip 107 are congruent square shapes. In Figure 9I , Figure 9J the reason why the sizes of the chips look different is that, compared with Figure 9HThe same situation is shown in the top view, where an example is given in which the phases of the first chip 105 and the second chip 107 are staggered by 45°. The diameter of the guide member 403 for the second chip is processed to be slightly larger than the length of the diagonal of the chip. In order to fix the first member 102 relative to the second member 103, first, the first member 102 is placed on the second member 103. At this moment, the insulating film 104 of the first chip 105 does not contact the insulating film 106 of the second chip 107. Through the above steps, alignment is performed in such a way that the center of the window 123 of the first chip 105 coincides with the center of the window 124 of the second chip 107. After that, a washer 126 is placed on the upper part of the first member 102, and a threaded cap 125 is covered thereon, causing the threaded structure 810 to engage with the threaded structure 811 of the second member 103 and rotating it to fix.

[0169] According to this modification example, by clamping the washer 126, when the threaded cap 125 is screwed in, the first member 102 can be pressed down without rotating the first member 102 relative to the second member 103 by using the frictional force acting between the first member 102, the second member 103, and the first seal 118, and the risk of film breakage can be reduced. The material of the washer 126 is selected to have a coefficient of friction that does not transmit the rotational movement of the threaded cap 125 to the first member 102.

[0170] As described above, various structural examples of the specimen holder have been explained. When it is assumed that there is less leakage of the specimen during the process of sandwiching a liquid specimen between the chips, or as in the fifth structural example (refer to Figures 7A - 7C ), etc., when the risk of the leaked liquid specimen contacting the electrode 108 is less, the following second design guideline can be applied instead of the first design guideline of the above-mentioned specimen holder (refer to Figure 3 ). Use Figure 18 to show the second design guideline of the specimen holder. Figure 18 shows the state where the upper sealing surface 205 of the cover member 111 contacts the first seal 118 in the state without a specimen. At this time, the insulating film 104 of the first chip 105 does not contact the insulating film 106 of the second chip 107. However, when aligning the first chip 105 and the second chip 107 in the state where the cover member 111 and the first seal 118 do not contact, Figure 18 is the state where the alignment is completed. The second design guideline can be defined as satisfying the condition that "at the moment when the alignment of the first chip 105 and the second chip 107 starts, the first seal 118 is not deformed" (key point 1) and the condition that "the first seal 118 is flattened simultaneously with or prior to the second seal 119" (key point 1).

[0171] In Figure 18In the case of the specimen holder 101 of the first structural example shown, it is only necessary to satisfy the relationships shown in the following (Equation 3) and (Equation 4). In Figure 3 the depth a of the guide, the distance b between the first sealing surfaces, and the distance c between the second sealing surfaces are defined. Additionally, the distance d from the lid member 111 to the insulating film 104 of the first chip 105 is defined (in this case, equal to the thickness of the first chip 105 + the thickness of the fixed seal 110).

[0172] Depth a of the guide + distance d > Distance c between the second sealing surfaces + Thickness of the first seal 118... (Equation 3)

[0173] By satisfying (Equation 3), it is ensured that the first chip 105 is in a state of being embedded in the guide 116.

[0174] ABS(Distance b between the first sealing surfaces - Distance c between the second sealing surfaces) ≤ Thickness of the first seal 118... (Equation 4)

[0175] By satisfying (Equation 4), when the upper sealing surface 205 of the lid member 111 contacts the first seal 118, it is ensured that the insulating film 104 of the first chip 105 does not contact the insulating film 106 of the second chip 107.

[0176] In this case, whether it is required to satisfy (Equation 3) also depends on the structure of the specimen holder. For example, in the case of performing high-precision alignment between chips using the component guide listed in the third structural example, etc., (Equation 3) may not be satisfied.

[0177] The effects of the specimen holder according to the second design guideline are as follows. In the specimen holder according to the first design guideline, if the first component 102 is placed on the second component 103 and then released, the entire self-weight of the first component 102 acts and the liquid specimen is flattened. In contrast, in the specimen holder according to the second design guideline, the first seal 118 becomes a buffer, and by pressing down the first component 102 while flattening the first seal 118 and the second seal 119, the speed of flattening the liquid specimen can be made relatively slow and uniform. The first design guideline and the second design guideline can be selected according to the short-circuit risk caused by the leakage of the liquid specimen and the influence of the introduction method of introducing the liquid specimen into the specimen holder on the specimen.

[0178] Example 2

[0179] When the gap between the insulating films sandwiching the liquid specimen is too thick, the signal intensity detected by the electrodes decreases. The gap between the insulating films is preferably maintained at a thickness slightly thicker than the object to be observed in the solution or gel material. Therefore, the specimen holder of Example 2 is provided with a mechanism for adjusting the gap between the insulating films by adjusting the pressure in the first space 120 and / or the second space 121 formed by the first seal 118 and the second seal 119.

[0180] Figures 10A - 10B A specimen holder 901 (eighth structural example) is shown in which a mechanism for decompressing the pressure in the first space 120 under high vacuum conditions for electron microscope observation is provided in the specimen holder of Example 1 (seventh structural example). The first space 120 is a space for placing a specimen sandwiched between insulating films. Figure 10A The state when the specimen holder 901 is arranged in an atmospheric pressure atmosphere is shown. Figure 10B The state when arranged in a high vacuum atmosphere is shown. The specimen holder 901 includes a gas passage 910 connecting the external atmosphere and the first space 120, and a decompression film 911 provided at the boundary between the gas passage 910 and the external atmosphere and having elasticity. As Figure 10B shown, the decompression film 911 expands outward under high vacuum conditions, whereby the first space 120 is decompressed compared to the state arranged in an atmospheric pressure atmosphere. On the other hand, the second space 121 sealed by the second seal 119 is not decompressed and remains at atmospheric pressure. That is, the second space 121 becomes relatively high pressure compared to the first space 120. As a result, the insulating film in the signal transmission window 124 of the second chip 107, and the insulating film and the conductive film in the electron beam irradiation window 123 of the first chip 105 are pressed from the electrode 108 side, and the gap between the electron beam irradiation window 123 and the signal transmission window 124 sandwiching the liquid specimen 115 can be kept small.

[0181] The decompression film 911 can be provided in the base material 127 in advance, or can be provided after the first member 102 and the second member 103 are combined into a state capable of electron microscope observation. When the decompression film 911 is arranged in the state where the first member 102 and the second member 103 are combined, during the process of combining the first member 102 and the second member 103, the first space 120 can maintain a state open to the external atmosphere. In the case of not having a gas passage connecting to the external atmosphere, by pressing the first member 102 against the second member 103, the first seal 118 is flattened, and correspondingly the volume of the first space 120 decreases, and there is a concern that the first space 120 may be pressurized above atmospheric pressure. By having a gas passage open to the external atmosphere, overpressurization of the first space 120 can be suppressed.

[0182] Figures 11A - 11C Shown is a specimen holder 1001 (ninth structural example) of the specimen holder in Example 1 (seventh structural example) provided with a mechanism for adjusting the pressure in the second space 121 by pressurizing or depressurizing under high-vacuum conditions for electron microscope observation. Figure 11A Shown is the state when the specimen holder 1001 is disposed in an atmospheric pressure atmosphere, Figure 11B Shown is the state when disposed in a high-vacuum atmosphere, Figure 11C Shown is the state when adjusting the pressure in the second space 121 in a high-vacuum atmosphere. The specimen holder 1001 includes a gas passage 1010 connecting the external atmosphere and the second space 121, a pressure-reducing membrane 1011 provided at the boundary between the gas passage 1010 and the external atmosphere and having elasticity, and a pressure adjustment mechanism 1012. The pressure adjustment mechanism 1012 adjusts the pressure in the second space 121 by changing the expansion mode of the pressure-reducing membrane 1011.

[0183] As Figure 11B shown, the pressure-reducing membrane 1011 expands outward under high-vacuum conditions, and thus is depressurized compared to the state where the second space 121 is disposed in an atmospheric pressure atmosphere. Therefore, the insulating film in the signal transmission window 124 of the second chip 107 expands outward when observing from the liquid specimen 115 due to the pressure difference between the first space 120 and the second space 121, and the laminated film of the insulating film and the conductive film in the electron beam irradiation window 123 of the first chip 105 expands outward due to the pressure difference between the external atmosphere and the first space 120. Therefore, as Figure 11C shown, the pressure adjustment mechanism 1012 pushes out the rod-shaped member 1013 in the direction of the arrow and raises the pressure-reducing membrane 1011 toward the second space 121 side. By changing the pushing-out amount of the rod-shaped member 1013, the pressure in the second space 121 can be adjusted to a state after being pressurized or depressurized from the initial atmospheric pressure. By appropriately pressurizing the second space 121, the insulating film in the signal transmission window 124 is pressed in a form with a relatively high pressure from the electrode 108 side, and the interval between the electron beam irradiation window 123 sandwiching the liquid specimen 115 and the signal transmission window 124 can be kept small.

[0184] As an example of the pressure adjustment mechanism 1012, a linear actuator can be cited. The pressure adjustment mechanism 1012 can be integrally formed with the specimen holder 1001, or can be provided on the holder on the electron microscope side that mounts the specimen holder 1001 during observation.

[0185] Also, the air pressure can be adjusted by the air pressure adjusting mechanism 1012 while confirming the image obtained by the electron microscope. The image is confirmed, and the pushing out of the rod-shaped member 1013 is stopped when the desired contrast is obtained. This is because the signal intensity becomes stronger as the second space 121 is pressurized more. On the other hand, if it is pressurized excessively, the risk of damage to the thin film of the chip becomes high.

[0186] Figure 12 Fig. shows a specimen holder 1101 (tenth structural example) provided with a mechanism for reducing the pressure of the first space 120 under high vacuum conditions for electron microscope observation and a mechanism for adjusting by pressurizing or reducing the pressure of the second space 121 in the specimen holder of Example 1 (seventh structural example). Figure 12 Fig. shows a state where the specimen holder 1101 is arranged in a high vacuum atmosphere and the pressure of the second space 121 is being adjusted. To adjust the pressure of the second space 121, the specimen holder 1101 is provided with a heater 1110 in the second space 121. The gas atmosphere in the second space 121 is expanded by the heater 1110, thereby pressurizing the second space 121. By appropriately pressurizing the second space 121 with the heater 1110, the insulating film 106 in the signal transmission window 124 is pressed in a form with a relatively high air pressure from the electrode 108 side, and the interval between the electron beam irradiation window 123 sandwiching the liquid specimen 115 and the signal transmission window 124 can be kept small. The air pressure can be adjusted by the heater 1110 while confirming the image obtained by the electron microscope.

[0187] Figure 13 Fig. shows a specimen holder 1201 (eleventh structural example) provided with a mechanism for reducing the pressure of the first space 120 under high vacuum conditions for electron microscope observation and a gas passage 1010 connecting the external atmosphere and the second space 121 and a sealing film 1210 in the specimen holder of Example 1 (seventh structural example). Figure 13 Fig. shows a state where the specimen holder 1201 is arranged in an atmospheric pressure atmosphere.

[0188] Similar to the eighth structural example, the mechanism for reducing the pressure of the first space 120 includes a gas passage 910 connecting the external atmosphere and the first space 120 and an extensible pressure reducing film 911.

[0189] On the other hand, the sealing film 1210 may or may not be stretchable. When the sealing film 1210 is stretchable, a pressure adjustment device may be provided in the same manner as in the ninth or tenth structural example so that the pressure in the second space 121 can be adjusted. In any case, in a high vacuum atmosphere, the second space 121 becomes relatively high pressure compared to the first space 120, whereby the distance between the window 123 for electron beam irradiation and the signal transmission window 124 sandwiching the liquid-like specimen 115 can be kept small.

[0190] In addition, when the sealing film 1210 is not stretchable, it is preferable to dispose the pressure reducing film 911 and the sealing film 1210 in a state where the first member 102 and the second member 103 are combined and electron microscope observation can be performed. Thereby, it is possible to suppress the second space 121 from being excessively pressurized due to the second seal 119 being flattened.

[0191] In addition, as the eighth to eleventh structural examples, an example in which a pressure adjustment mechanism is applied to a specimen holder corresponding to the seventh structural example is shown, but it can also be applied to other structural examples or modified examples described in Example 1.

[0192] In Figures 10A - 10B the specimen holder of the eighth structural example shown, there is provided a mechanism for decompressing the first space 120 using the gas passage 910 and the pressure reducing film 911. On the other hand, in order to reduce the number of components and the operation process, it is also possible to implement a decompression mechanism by making the first seal 118 and the second seal 119 an integral type and using the film connecting the first seal and the second seal as the pressure reducing film 911.

[0193] Figures 14A - 14C A specimen holder 1301 (twelfth structural example) is shown in which a mechanism for decompressing the pressure in the first space 120 under high vacuum conditions for electron microscope observation is provided in the specimen holder of Example 1 (sixth structural example). As described above, the specimen holder 1301 uses a sealing member 1310 with a pressure reducing film function in which the first seal 118 and the second seal 119 are integrated. Figure 14A A state where the specimen holder 1301 is disposed in an atmospheric pressure atmosphere is shown, Figure 14B and a state where it is disposed in a high vacuum atmosphere is shown. And, Figure 14C is a view looking down on the second member 103 from the electron beam irradiation direction. However, in Figure 14C in order to show the structure in an easy-to-understand manner, a part of the second chip 107 is cut away, and the actual shape of the second chip 107 is a rectangle shown by a dotted line. And the integral sealing member 1310 with a pressure reducing film function is omitted.

[0194] In a state where the first component 102 is fixed to the second component 103 of the sample holder 1301, the seal 1310 with a pressure-reducing film provided in the second component 103 seals the first space 120 and the second space 121 by the first seal portion 118' and the second seal portion 119', respectively. Further, the second component 103 has a third space 1311 directly below the pressure-reducing film portion 911' located between the first seal portion 118' and the second seal portion 119'. The third space 1311 is connected to the external atmosphere through a gas passage 910. As Figure 14B shown, the pressure-reducing film portion 911' expands outward under high-vacuum conditions, so that the first space 120 is decompressed compared to the state where it is disposed in the atmospheric pressure atmosphere. As a result, the second space 121 becomes relatively high pressure compared to the first space 120. As a result, the insulating film in the signal transmission window 124 of the second chip 107, and the insulating film and the conductive film in the electron beam irradiation window 123 of the first chip 105 are pressed from the electrode 108 side, and the interval between the electron beam irradiation window 123 and the signal transmission window 124 sandwiching the liquid sample 115 can be kept small.

[0195] Figure 15 The shape (schematic diagram) of the seal 1310 with a pressure-reducing film is shown. The uppermost figure shows the Figure 14C A-A cross-sectional view shown in FIG., and the plan views of C-C, D-D, E-E, and F-F in this cross-sectional view are shown below. The seal 1310 having a pressure-reducing film function has an O-ring-shaped first seal portion 118' and an O-ring-shaped second seal portion 119', and the two are connected by a pressure-reducing film portion 911'. The pressure-reducing film portion 911' is provided with a guide portion 116' arranged along a guide 116 provided on the base material 127 of the second component 103. As Figure 14A shown, the guide portion 116' is used for aligning the first chip 105 and the second chip 107.

[0196] In addition, as a twelfth structural example, an example in which a seal with a pressure-reducing film is applied to a sample holder corresponding to the sixth structural example is shown, but it can also be applied to other structural examples or modified examples described as Example 1. Further, the seal 1310 having a pressure-reducing film function can also be used as a seal that integrates the first seal and the second seal without using the pressure-reducing film function.

[0197] Figures 16A - 16C A sample holder 1401 (thirteenth structural example) is shown in which a mechanism for decompressing the pressure in the first space 120 under high-vacuum conditions for electron microscope observation is provided in the sample holder of Example 1 (sixth structural example). Figure 16AShows a state where the first component 102 is arranged in an atmospheric pressure atmosphere in a state fixed to the second component 103. Figure 16B Shows a state where the first component 102 is arranged in a high vacuum atmosphere in a state fixed to the second component 103. And, Figure 16C Is a view looking down on the second component 103 from the electron beam irradiation direction. However, in Figure 16C , in order to show the structure understandably, a part of the second chip 107 is cut away for display, and the actual shape of the second chip 107 is a rectangle shown by a dotted line. In addition, Figures 16A - 16B Is Figure 16C The cross-sectional view taken along the line A-A shown.

[0198] The second component 103 of the sample holder 1401 includes a sheet-like seal 1402 having a decompression film function as the second seal. As the sheet-like seal 1402 having a decompression film function, a double-sided tape can be used, and the double-sided tape has a structure in which a Si rubber sheet 140 is sandwiched by Si-based adhesive sheets 150 having uniform surfaces on both sides. The second component 103 of the sample holder 1401 includes a guide 116 for aligning the second chip 107 with respect to the second component 103 using the four corners of the second chip 107. The guide 116 is the same as that in the first embodiment (the sixth structural example), and is also used for aligning the first chip 105 and the second chip 107 when the first component 102 and the second component 103 are fixed.

[0199] The second component 103 has a third space 1311 in a part of the second bottom sealing surface 200. The third space 1311 is connected to the external atmosphere through a gas passage 910.

[0200] Figure 17 Shows the shape (schematic diagram) of the sheet-like seal 1402 having a decompression film function. As Figure 17 Shown, the sheet-like seal 1402 having a decompression film function is adhesively bonded to the second bottom sealing surface 200 without interfering with the guide 116. In the drawing, the position of the guide 116 at the time of adhesion is shown by a dotted line. And, the sheet-like seal 1402 having a decompression film function has an electrode center hole 1403 for avoiding contact with the electrode 108.

[0201] The second chip 107 is bonded and fixed to the sheet-like seal 1402 with a decompression film function in a state where it is aligned with the center of the electrode 108 centered by the guide member 116. The sheet-like seal 1402 with a decompression film function has the function of a second seal, and in a state where the first member 102 and the second member 103 are fixed, it hermetically isolates the second space 121 from the first space 120. Further, the sheet-like seal 1402 with a decompression film function isolates the third space 1311 from the first space 120, and hermetically isolates the first space 120 from the external environment maintained at a high vacuum atmosphere for electron beam irradiation.

[0202] As Figure 16B shown, when the specimen holder 1401 is placed under high vacuum conditions, the sheet-like seal 1402 with a decompression film function expands toward the high vacuum atmosphere side at the position where the third space 1311 is located directly below. Thereby, the first space 120 is decompressed compared to the state where it is disposed in the atmospheric pressure atmosphere. As a result, the second space 121 becomes relatively high pressure compared to the first space 120. As a result, the insulating film in the signal transmission window 124 of the second chip 107, and the insulating film and the conductive film in the electron beam irradiation window 123 of the first chip 105 are pressed from the electrode 108 side, and the interval between the electron beam irradiation window 123 and the signal transmission window 124 sandwiching the liquid-like specimen 115 can be kept small.

[0203] In addition, as a thirteenth structural example, an example in which a seal with a decompression film is applied to a specimen holder corresponding to the sixth structural example is shown, but it can also be applied to other structural examples described as Example 1 or modified examples thereof.

[0204] Example 3

[0205] Figure 19 A structural diagram of a charged particle beam apparatus is shown. The housing 2010 includes a column 2610 having an electron optical system for irradiating an electron beam to a specimen as an observation object, and a specimen chamber 2600 for mounting the specimen. The electron optical system includes an electron gun 2011, a condenser lens 2060 and an objective lens 2062 for focusing the electron beam 2012 emitted from the electron gun 2011 and irradiating it to the specimen, an astigmatism corrector 2061 for correcting the astigmatism of the electron beam 2012, and a deflector 2013 for two-dimensionally scanning the electron beam 2012 on the specimen. In the specimen chamber 2600, a detector 2017 for detecting an electron signal generated from the specimen and a vacuum evacuation system 2000 for maintaining the inside of the housing 2010 in a vacuum are provided. A worktable 2064 capable of three-dimensional movement is provided in the specimen chamber 2600. The base material 127 of the specimen holder and the electrode 108 described as Example 1 or Example 2 are assembled on the worktable 2064.

[0206] The main control unit 2014 is connected to a computer 2015 to which a display unit 2016 is connected. A user operates the scanning electron microscope using a graphical user interface (GUI) on the computer 2015 and the display unit 2016. The computer 2015 transmits commands input by the user using the GUI to the main control unit 2014, and the main control unit 2014 controls the electron optical system, the vacuum exhaust system 2000, the stage 2064, and other structural units (not shown) of the scanning electron microscope according to the commands. In addition, the computer 2015 receives signal data from the detector 2017 or the electrode 108 received by the main control unit 2014 and displays it as an image on the display unit 2016.

[0207] The user places the first seal 118, the second seal 119, and the second chip 107 on the base material 127 assembled on the stage 2064, drops the liquid specimen 115, fixes the first component 102, and then performs observation.

[0208] Alternatively, it is also possible to assemble the electrode 108, which is the specimen holder described in Example 1 or Example 2, on the stage 2064 (in this case, the charged particle beam apparatus is equivalent to the apparatus obtained by removing the base material 127 from the Figure 19 charged particle beam apparatus shown). The user places the base material 127 on the electrode 108 to obtain the Figure 19 state shown, and then similarly observes the specimen.

[0209] Explanation of symbols

[0210] 101, 301, 401, 501, 601, 701, 801, 901, 1001, 1101, 1201, 1301, 1401—specimen holder, 102—first component, 103—second component, 104—insulating film, 105—first chip, 106—insulating film, 107—second chip, 108—electrode, 109—conductive film, 110—fixed seal, 111—cover component, 112—electron beam irradiation surface, 113—inclined surface, 114—conductive paste, 115—liquid specimen, 116—guide, 116’—guide portion, 117—threaded member, 118—first seal, 118’—first seal portion, 119—second seal, 119’—second seal portion, 120—first space, 121—second space, 122—specimen, 123—electron beam irradiation window, 124—signal transmission window, 125—threaded cap, 125a—opening, 126—washer, 127—base material, 128—through hole, 129—threaded hole, 130—chip recess portion, 140—Si rubber sheet, 150—Si-based adhesive sheet, 200—second bottom seal surface, 203—first bottom seal surface, 204—distance between second seal surfaces, 205—upper seal surface, 302—liquid accumulation portion, 402—guide for first chip, 403—guide for second chip, 404—guide for second component, 405—guide for first component, 510—adhesive material, 702—fixing hook portion, 703—warping portion for hook portion, 704—guide for first hook portion, 705—guide for second hook portion, 810, 811—thread structure, 910—gas passage, 911—pressure reducing film, 911’—pressure reducing film portion, 1010—gas passage, 1011—pressure reducing film, 1012—air pressure adjustment mechanism, 1013—rod-shaped member, 1110—heater, 1210—sealing film, 1310—seal with pressure reducing film function, 1311—third space, 1402—sheet seal with pressure reducing film function, 1403—central hole for electrode, 2000—vacuum exhaust system, 2010—box body, 2011—electron gun, 2012—electron beam, 2013—deflector, 2014—main control unit, 2015—computer, 2016—display unit, 2017—detector, 2060—condensing lens, 2061—astigmatism corrector, 2062—objective lens, 2064—workbench, 2600—specimen chamber, 2610—column.

Claims

1. A specimen holder, which is a specimen holder for holding a liquid or gel-like specimen, is characterized in that comprising: a first component having a lid member and a first chip, the lid member having an opening, being made of metal or having at least an electron beam irradiated surface and the side surfaces of the opening covered with a metal film, the first chip having a first window of a stacked film formed with a conductive thin film and a first insulating thin film, and being held on a surface of the lid member facing the electron beam irradiated surface such that the conductive thin film is exposed from the opening of the lid member; and a second component having a first seal, a second seal, a base material formed with a first bottom sealing surface for disposing the first seal and a second bottom sealing surface for disposing the second seal, an electrode disposed on the base material, and a second chip having a second window formed with a second insulating thin film, and being held on the second bottom sealing surface via the second seal such that the second window faces the electrode, the conductive thin film of the first chip is electrically connected to the metal of the lid member, the specimen holder has a guide for the opposed chip, and the guide for the opposed chip is provided on the base material according to the position of the first chip when the first component and the second component are combined, or is provided on the lid member according to the position of the second chip when the first component and the second component are combined, the first component and the second component are combined, and the first seal is flattened between the first bottom sealing surface and the upper sealing surface of the lid member, whereby a region inside the first seal is kept airtight with respect to a region outside the first seal.

2. The specimen holder according to claim 1, wherein when the first component and the second component are arranged such that the first insulating thin film and the second insulating thin film are in surface contact with each other, a contact surface of the first insulating thin film and the second insulating thin film is located between the base material or the lid member provided with the guide for the opposed chip and the front end of the guide for the opposed chip, and a distance between the first bottom sealing surface of the base material and the upper sealing surface of the lid member is larger than the thickness of the first seal.

3. The specimen holder according to claim 1, wherein when the centers of the first window of the first chip and the second window of the second chip are aligned and the first component and the second component are arranged such that the upper sealing surface of the lid member contacts the first seal, there is a height at which the first insulating thin film and the second insulating thin film do not contact each other.

4. The specimen holder according to claim 1, wherein the first chip is held by a guide for the first chip provided on the lid member.

5. The specimen holder according to claim 1, wherein the base material has a recess having the second bottom sealing surface as a bottom surface, and the guide for the opposed chip is a side wall of the recess.

6. The specimen holder according to claim 1, wherein The above-mentioned base material has a recess with the second bottom sealing surface as a part of its bottom surface, and the opposing chip guide is a plate-shaped guide provided at a position in the recess opposite to the side of the first chip when the first component and the second component are combined.

7. The specimen holder according to claim 1, characterized in that, Comprising: A hook portion; and A warping portion for engaging with the hook portion, Either the hook portion or the warping portion is provided on the first component, and the other of the hook portion and the warping portion is provided on the second component.

8. A specimen holder is a specimen holder for holding a specimen in a liquid or gel state, characterized in that, Having: A first component having a cover component and a first chip. The cover component has an opening portion, is made of metal or at least the electron beam irradiation surface and the side surface of the opening portion are covered with a metal film. The first chip has a first window with a laminated film formed with a conductive thin film and a first insulating thin film, and is held on the surface of the cover component opposite to the electron beam irradiation surface in such a manner that the conductive thin film is exposed from the opening portion of the cover component; and A second component having a first seal, a second seal, a base material formed with a first bottom sealing surface for disposing the first seal and a second bottom sealing surface for disposing the second seal, an electrode disposed on the base material, and a second chip. The second chip has a second window formed with a second insulating thin film, and is held on the second bottom sealing surface via the second seal in such a manner that the second window faces the electrode, The conductive thin film of the first chip is electrically connected to the metal of the cover component, A first-component guide is provided on the base material, and a second-component guide is provided on the surface of the cover component opposite to the electron beam irradiation surface. The first-component guide and the second-component guide have a height such that the first insulating thin film and the second insulating thin film do not contact when the first-component guide and the second-component guide contact each other, The first component and the second component are combined, and the first seal is flattened between the first bottom sealing surface and the upper sealing surface of the cover component, whereby the region inside the first seal is kept airtight with respect to the region outside the first seal.

9. The specimen holder according to claim 8, wherein A second-chip guide corresponding to the position of the second chip is provided on the base material, The front end of the second-chip guide is located below the second insulating thin film of the second chip.

10. The specimen holder according to claim 9, wherein The base material has a recess with the second bottom sealing surface as a part of its bottom surface, and the second-chip guide is a plate-shaped guide provided at a position in the recess opposite to the side of the second chip.

11. The specimen holder according to claim 10, wherein The first-component guide is a side wall of the recess, and the second-component guide is a plate-shaped guide provided at a position corresponding to the side wall of the recess when the first component and the second component are combined.

12. The specimen holder according to claim 8, wherein The above-mentioned first chip is held by a guide for the first chip provided in the above-mentioned lid member.

13. The specimen holder according to claim 8, wherein the area of the surface of the above-mentioned first chip on which the above-mentioned first insulating film is formed is different from the area of the surface of the above-mentioned second chip on which the above-mentioned second insulating film is formed.

14. The sample holder according to claim 8, characterized in that, It has: a hook portion; and a warping portion for engaging with the above-mentioned hook portion, either the hook portion or the warping portion is provided on the above-mentioned first member, and the other of the hook portion and the warping portion is provided on the above-mentioned second member.

15. A specimen holder is a specimen holder for holding a specimen in a liquid or gel state, characterized in that, It has: a first member having a lid member and a first chip, the lid member having an opening portion, being made of metal or having at least its electron beam irradiation surface and the side surface of the opening portion covered with a metal film, the first chip having a first window with a laminated film formed with a conductive film and a first insulating film, and being held on the surface of the lid member facing the electron beam irradiation surface so that the conductive film is exposed from the opening portion of the lid member; and a second member having a first seal, a second seal, a base material having a first bottom sealing surface for arranging the first seal and a second bottom sealing surface for arranging the second seal, an electrode arranged on the base material, and a second chip, the second chip having a second window formed with a second insulating film, and being held on the second bottom sealing surface via the second seal so that the second window faces the electrode, the conductive film of the above-mentioned first chip is electrically connected to the metal of the above-mentioned lid member, in the above-mentioned lid member, a guide for the opposed chip corresponding to the position of the above-mentioned second chip when the above-mentioned first member and the above-mentioned second member are combined is provided, the above-mentioned first member and the above-mentioned second member are combined, and the first seal is flattened between the first bottom sealing surface and the upper sealing surface of the above-mentioned lid member, whereby the area inside the first seal is kept airtight with respect to the area outside the first seal, the above-mentioned base material has a cylindrical shape with a first thread structure on its outer peripheral portion, the above-mentioned lid member extends in a direction perpendicular to the electron beam irradiation surface, and has a peripheral portion on its inner wall, and the peripheral portion has a second thread structure that engages with the above-mentioned first thread structure, in a state where the first thread structure and the second thread structure are not engaged and the first member is placed on the second member, the front end of the guide for the opposed chip is located below the second insulating film of the above-mentioned second chip.

16. The specimen holder according to claim 15, wherein it has a locking mechanism that restricts the amount of rotation of the above-mentioned base material relative to the above-mentioned lid member when the first thread structure and the second thread structure are engaged to combine the above-mentioned first member and the above-mentioned second member.

17. The specimen holder according to claim 16, wherein the above-mentioned base material has a concave portion having the above-mentioned second bottom sealing surface as a part of its bottom surface, and the amount of rotation of the above-mentioned base material relative to the above-mentioned lid member is restricted by bringing the side wall of the concave portion into contact with the guide for the opposed chip.

18. A specimen holder is a specimen holder for holding a specimen in a liquid or gel state, characterized in that, having: a first component having a lid component and a first chip, the lid component having an opening, being made of metal or having at least an electron beam irradiation surface and the side surface of the opening covered with a metal film, the first chip having a first window of a laminated film formed with a conductive thin film and a first insulating thin film, and being held on a surface of the lid component facing the electron beam irradiation surface such that the conductive thin film is exposed from the opening of the lid component; and a second component having a first seal, a second seal, a base material formed with a first bottom sealing surface for disposing the first seal and a second bottom sealing surface for disposing the second seal, an electrode disposed on the base material, and a second chip, the second chip having a second window formed with a second insulating thin film, and being held on the second bottom sealing surface via the second seal such that the second window faces the electrode, the conductive thin film of the first chip is electrically connected to the metal of the lid component, a second chip guide and a first component guide for disposing the second chip are provided on the base material, and a second component guide is provided on a surface of the lid component facing the electron beam irradiation surface, and the first component guide and the second component guide have a height such that the first insulating thin film and the second insulating thin film do not contact when the first component guide and the second component guide contact each other, the first component and the second component are combined, and the first seal is flattened between the first bottom sealing surface and an upper sealing surface of the lid component, whereby a region inside the first seal is kept airtight with respect to a region outside the first seal, in a state where the first component and the second component are combined, the second chip guide, the first component guide, and the second component guide are concentrically shaped.

19. The specimen holder according to claim 18, wherein: the base material has a cylindrical shape having a first thread structure on its outer peripheral portion, the lid component extends in a direction perpendicular to the electron beam irradiation surface, and has a peripheral portion on its inner wall, the peripheral portion having a second thread structure meshing with the first thread structure, by meshing the first thread structure with the second thread structure, the first component and the second component are combined.

20. The specimen holder according to claim 18, wherein: it includes a threaded lid having an opening through which an electron beam passes, the base material has a cylindrical shape having a first thread structure on its outer peripheral portion, the threaded lid extends in a direction perpendicular to the surface provided with the opening, and has a peripheral portion on its inner wall, the peripheral portion having a second thread structure meshing with the first thread structure, by disposing the first component between the threaded lid and the second component and meshing the first thread structure with the second thread structure, the first component and the second component are combined.

21. The specimen holder according to claim 20, wherein: A disc-shaped washer is disposed between the above-mentioned threaded cap and the above-mentioned first component.

22. The specimen holder according to any one of claims 1 to 14, characterized in that the above-mentioned first seal is an O-ring, and the above-mentioned second seal is a double-sided tape formed by sandwiching an Si rubber sheet with an adhesive sheet.

23. The specimen holder according to any one of claims 1 to 14, characterized in that the above-mentioned first seal and the above-mentioned second seal are integrally formed.

24. The specimen holder according to any one of claims 1 to 21, characterized in that the above-mentioned first seal and the above-mentioned second seal are O-rings.

25. The specimen holder according to any one of claims 1 to 21, characterized in that it has a first space for placing the above-mentioned specimen sandwiched between the above-mentioned first insulating film and the above-mentioned second insulating film, the above-mentioned base material has a gas passage connected to the above-mentioned first space, and a pressure-reducing film provided at the boundary between the above-mentioned gas passage and the external atmosphere.

26. The specimen holder according to any one of claims 1 to 21, characterized in that it has a second space surrounded by the above-mentioned second chip, the above-mentioned second seal, and the above-mentioned second bottom seal surface, the above-mentioned base material has a gas passage connected to the above-mentioned second space, and a pressure-reducing film provided at the boundary between the above-mentioned gas passage and the external atmosphere.

27. The specimen holder according to claim 26, characterized in that the pressure of the above-mentioned second space is adjusted by causing an expansion change of the above-mentioned pressure-reducing film.

28. The specimen holder according to any one of claims 1 to 21, characterized in that, It has: a first space for placing the above-mentioned specimen sandwiched between the above-mentioned first insulating film and the above-mentioned second insulating film; and a seal with a pressure-reducing film, which has a first sealing portion functioning as the above-mentioned first seal, a second sealing portion functioning as the above-mentioned second seal, and a pressure-reducing film portion connecting the above-mentioned first sealing portion and the above-mentioned second sealing portion, the above-mentioned base material is provided with a third space separated from the above-mentioned first space by the above-mentioned pressure-reducing film portion, and a gas passage connecting the above-mentioned third space and the external atmosphere.

29. The sample holder according to any one of claims 1 to 21, characterized in that, It has: a first space for placing the above-mentioned specimen sandwiched between the above-mentioned first insulating film and the above-mentioned second insulating film; and a sheet-shaped seal with a pressure-reducing film function, which functions as the above-mentioned second seal, the above-mentioned base material is provided with a third space separated from the above-mentioned first space by the above-mentioned sheet-shaped seal with a pressure-reducing film function, and a gas passage connecting the above-mentioned third space and the external atmosphere.

30. The specimen holder according to claim 29, characterized in that the above-mentioned sheet-shaped seal with a pressure-reducing film function is a double-sided tape formed by sandwiching an Si rubber sheet with an adhesive sheet.

31. The specimen holder according to any one of claims 1 to 21, characterized in that at least a part of the above-mentioned second component is loaded into the workbench of the charged particle beam device.

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