Sample holder for hydrogen permeation detection and hydrogen permeation diffusion path observation device

Abstract

This invention provides a sample holder for electrochemically supplemented hydrogen permeation detection using an electrolyte, and a hydrogen permeation diffusion path observation device for measuring hydrogen ions passing through a sample held in the sample holder. The sample holder (30) includes: a holder body (31) for holding a sample (17); an electrolyte inlet chamber (31b) having an opening (31c) relative to a measurement area (17a) of the sample; a pressing plate (33) having a through hole (33a) corresponding to the measurement area, pressing the sample from the electron source side around the through hole, thereby airtightly clamping the sample between the plate and the holder body; and a dual-phase plate. A heavy sealing member (32) is disposed between the surface of the support body and the sample in such a way that it surrounds the measurement area of ​​the sample; a differential exhaust pipe (35) is opened between the sealing members on the surface of the support body and exhausts gas from the opening; and an electrode (19) includes a bias voltage application electrode (19a) and a counter electrode (36) for electrolysis, wherein a pressing plate is made of conductive material as the bias application electrode, and the counter electrode is disposed in the electrolyte inlet chamber, and a voltage is applied between the bias voltage application electrode and the counter electrode to electrolyze the electrolyte (34) and introduce the generated hydrogen ions into the sample.

Description

Technical Field

[0001] The present invention relates to a sample holder for holding a sample for hydrogen permeation detection and a hydrogen permeation diffusion path observation device for measuring hydrogen permeation through the sample, and particularly to a sample holder for holding a plate-shaped sample as a sample holder that can enter and exit an analysis chamber when observing hydrogen atoms passing through the back of the plate-shaped sample and gushing out from the surface of the sample using a scanning electron microscope, and a hydrogen permeation diffusion path observation device for measuring hydrogen ions using the sample holder. Background Technology

[0002] Conventionally, to detect hydrogen permeating a sample, a hydrogen permeation diffusion path observation device disclosed in Patent Document 1 has been used, for example. This device includes a scanning electron microscope (SEM), which has a diaphragm-type vacuum container housing an analysis chamber and a sample, and a hydrogen piping connected to the diaphragm-type vacuum container to supply hydrogen to the back side of the sample. The sample acts as a diaphragm separating the analysis chamber from the hydrogen chamber of the diaphragm-type vacuum container. Using this observation device, an electron beam scans the sample to obtain a scanning electron microscope image (SEM image) of the sample surface. Simultaneously, hydrogen emanating from the sample surface is excited by the electron beam to become hydrogen ions and detach from the surface (this is referred to as an ESD (Electron Stimulated Desorption) component). Together with the SEM image, a hydrogen ion-based ESD image is obtained.

[0003] According to this hydrogen permeation diffusion path observation device, hydrogen gas is supplied from the back side of a thin plate sample, causing the hydrogen gas that permeates from the surface of the sample into the ultra-high vacuum chamber to escape by electron migration excited detachment (ESD), and its permeation location is measured. As described above, in this observation device, the sample functions as a diaphragm separating the analysis chamber and the hydrogen chamber. Hydrogen gas is introduced into the hydrogen chamber on the back side of the sample, and the hydrogen gas permeates through the sample and flows out from its surface towards the sample surface side, thereby allowing hydrogen permeation. Here, ultra-high vacuum refers to, for example, 10... -8 The air pressure at the Pa level.

[0004] However, in hydrogen permeation methods using hydrogen-based samples, the amount of hydrogen introduced relative to the sample is relatively small, resulting in a low hydrogen signal intensity during hydrogen permeation detection. This leads to longer measurement times and a low signal-to-noise ratio. Therefore, from the viewpoint of increasing the amount of hydrogen introduced and thus increasing the signal intensity of the transmitted hydrogen, it is possible to consider using electrochemical methods to introduce hydrogen ions into the solution instead of hydrogen gas.

[0005] On the other hand, Patent Document 2 discloses a method for supplying hydrogen from an electrolyte to a thin-plate sample in the atmosphere. Furthermore, although the solution unit used in the electron microscope in the high vacuum environment has been commercialized for SEM images and transmission electron microscope images (hereinafter referred to as TEM images), it does not correspond to an ultra-high vacuum environment.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application No. 2017-187457;

[0009] Patent document 2: M. Koyama, et al / Scripta Materialia 129(2017)pp.48-51. Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] Existing solution units correspond to low vacuum and high vacuum, but in low vacuum and high vacuum environments, in addition to hydrogen, there are also water, nitrogen and other substances remaining. Therefore, they cannot be said to be suitable for use in ultra-high vacuum environments where hydrogen measurement is the purpose.

[0012] Furthermore, in order to remove the influence of water in hydrogen measurement in an ultra-high vacuum environment, the vacuum container, sample holder, and sample need to undergo heating and degassing treatment, i.e., baking. Therefore, in order to withstand baking, the vacuum container, sample holder, and sample need to have a heat resistance of about 120°C, and the electrolyte must be removed during baking.

[0013] Furthermore, for the ultra-high vacuum environment required for hydrogen measurement, a solution unit with airtightness that does not disturb the ultra-high vacuum environment is needed to supply hydrogen.

[0014] Measures must also be taken to prevent damage to the sample and the support. Therefore, in order to release the bubbles generated from the solution during electrolytic treatment, it is necessary to connect a solution tube to the outside of the vacuum container to circulate the solution, or to equip the electrolyte inlet chamber in the sample support with a gas tube that connects the electrolyte inlet chamber to the outside of the vacuum container in order to release the bubbles from the electrolyte inlet chamber.

[0015] Thus, in order to perform electrochemically supplemented hydrogen permeation detection using an electrolyte in an ultra-high vacuum environment, the following conditions are required: no gas emissions that would disturb the ultra-high vacuum environment; the ability to bake the sample to above 100°C; the ability to electrochemically introduce hydrogen into the sample from the back (inside); for this purpose, changing the sample potential in a way that allows the electrodes to be configured in a small space without affecting the measured hydrogen ions; and the ability to release the gases released during the electrolysis process.

[0016] To address the above-mentioned issues, the first objective of this invention is to provide a sample holder for electrochemically supplemented hydrogen permeation detection using an electrolyte in an ultra-high vacuum environment. Another objective is to provide a hydrogen permeation diffusion path observation device that measures hydrogen ions passing through a sample held in the sample holder.

[0017] means for solving problems

[0018] To achieve the first objective of this invention, the electrochemically supplemented hydrogen permeation detection sample holder of this invention is characterized by comprising:

[0019] The main support is mounted on a scanning electron microscope and holds the sample used to detect hydrogen ions generated by electron beam irradiation;

[0020] The electrolyte inlet chamber has an opening that is open relative to the measurement area of ​​the sample;

[0021] The pressing plate has through holes corresponding to the measurement area of ​​the sample. The sample is pressed from the electron source side of the scanning electron microscope around the through holes, thereby clamping the sample in an airtight manner between the plate and the support body.

[0022] A double-sealed component is configured between the surface of the support body and the sample in a manner that surrounds the measurement area of ​​the sample.

[0023] A differential exhaust pipe opens between two sealing components on the surface of the support body and exhausts gas from that opening; and

[0024] The electrodes include a biasing electrode and a counter electrode for electrolysis.

[0025] The hydrogen permeation detection sample holder is configured to have a pressing plate as the bias electrode made of a conductive material, and a counter electrode disposed in the electrolyte inlet chamber, and to introduce hydrogen from the electrolyte into the sample by applying a voltage between the bias electrode and the counter electrode.

[0026] According to the present invention, in the hydrogen permeation diffusion path observation device, within the ultra-high vacuum analysis chamber, the surface of the support body is held in a gas-tight contact with the pressure plate while clamping the sample via double sealing components. A differential exhaust pipe is used to exhaust gas from the annular space defined between the double sealing components, thereby reliably maintaining the ultra-high vacuum within the analysis chamber and preventing gas release from the sample support side to the analysis chamber side. Furthermore, by applying a voltage to the electrolyte between the pressure plate (which serves as a bias voltage application electrode) and the counter electrode, a large number of hydrogen ions are generated from the electrolyte. These hydrogen ions are attracted toward the pressure plate, electrochemically introducing hydrogen into the sample. Therefore, compared to conventional hydrogen introduction to the sample via gas, the amount of hydrogen introduced into the sample is increased. Consequently, the signal intensity of the permeated hydrogen increases, thus shortening the time required for hydrogen permeation detection and increasing the signal-to-noise ratio (S / N) of the detection result. Furthermore, even when using conventional hydrogen gas for hydrogen introduction, hydrogen permeation detection can be performed on samples where the hydrogen permeation is below the detection limit.

[0027] The electrolyte introduction chamber includes an opening on the surface of the support body and a hollow section inside the support body extending from the opening. An insulating and corrosion-resistant coating is applied to the inner surface of the hollow section. When a counter electrode is arranged inside the hollow section, a large capacity of electrolyte can be electrolyzed through the hollow section, increasing the amount of hydrogen used for hydrogen introduction into the sample and improving the hydrogen introduction efficiency.

[0028] If the electrolyte inlet chamber is divided by the back of the sample, the inner sealing component of the double-sealed structure, and the surface of the support body, then the overall sample support structure can be made smaller because the electrolyte inlet chamber on the surface of the support body is divided by the back of the sample and the inner sealing component. In this method, it is only necessary to connect the counter electrode to the support body.

[0029] The sample holder includes a supply pipe for supplying electrolyte to the electrolyte inlet chamber and a discharge pipe for discharging used electrolyte. Therefore, even during electrolysis, fresh electrolyte is continuously supplied to the electrolyte inlet chamber, and even if unwanted bubbles are generated due to electrolysis, they are discharged to the outside along with the electrolyte through the discharge pipe, eliminating the effects of electrolysis caused by bubbles.

[0030] If the support body, counter electrode, electrolyte inlet chamber, and sealing component are made of a material that can be baked, water can be removed by baking the support body, counter electrode, electrolyte inlet chamber, and sealing component at a temperature of, for example, above 100°C before hydrogen permeation detection, thereby reliably performing hydrogen permeation detection. If the support body is made of a conductive material and functions as the counter electrode, there is no need to configure an additional counter electrode, reducing component and assembly costs.

[0031] Alternatively, the hollow portion of the electrolyte inlet chamber can be opened on the back side of the support body, thereby sealing the opening end by a cover component via an ultra-high vacuum seal. The cover component is supported by an elastic component on its surface side to form a container for the electrolyte inlet chamber. The upper end of the container opening is brought into contact with the back side of the sample by the force of the elastic component in the sealed hollow portion.

[0032] Based on the above structure, since the outer area of ​​the container is not a vacuum, the supply pipe, discharge pipe, counter electrode, and wiring can be general products instead of vacuum-specific components. Therefore, overall material costs are reduced. Furthermore, by removing the cover component from the support body, maintenance of the supply pipe, discharge pipe, counter electrode, and wiring is possible.

[0033] The hydrogen permeation diffusion path observation device of the present invention includes:

[0034] Scanning electron microscopes are used to detect secondary electrons generated when a sample is irradiated with an electron beam.

[0035] A hydrogen permeation detection sample holder is mounted on a scanning electron microscope and holds the sample, which is used to detect hydrogen ions generated by irradiation with an electron beam.

[0036] A hydrogen ion detection device detects hydrogen ions generated by an electron beam irradiating hydrogen, which escapes from the back of a sample held in a sample holder to the surface.

[0037] The sample holder comprises: a holder body; a pressing plate for pressing the sample from the surface of the holder body; a differential vent pipe with an opening between hermetically sealed components on the surface of the holder body to communicate with the outside; and electrodes, including a biasing electrode and a counter electrode for electrolyzing the electrolyte.

[0038] The main body of the support structure includes:

[0039] The electrolyte inlet chamber has an opening that is open relative to at least the measurement area of ​​the sample;

[0040] The electrolyte is filled into the back of the sample in the electrolyte introduction chamber; and

[0041] A double-sealed component is positioned on the surface of the sample holder body to surround the measurement area of ​​the sample.

[0042] The pressing plate has through holes corresponding to the measurement area of ​​the sample. The sample is pressed from the electron source side around these through holes, thereby airtightly clamping the sample between the sample holder and the double-sealed components.

[0043] The device is configured as follows: with electrolyte introduced into the electrolyte inlet chamber and the sample mounted on the sample holder, the electrolyte inlet chamber is completely sealed; a pressure plate is used as a bias electrode; and a counter electrode is disposed in the electrolyte inlet chamber. Electrolysis is performed by applying a voltage between the electrodes. An electron beam is used to irradiate hydrogen ions emerging from the back of the sample held on the sample holder towards its surface. The hydrogen ions generated by the electron beam are then measured using a hydrogen ion detection device. The sample holder has the same structure as the sample holder described above for achieving the first objective of this invention.

[0044] Invention Effects

[0045] According to the present invention, an electrochemically supplemented hydrogen permeation detection sample holder for electrochemically supplemented hydrogen permeation detection using an electrolyte in an ultra-high vacuum environment, and a hydrogen permeation diffusion path observation device for measuring hydrogen ions passing through a sample held on the sample holder and acquiring ESD images with high precision together with SEM images are provided. Attached Figure Description

[0046] Figure 1 This is a partial cross-sectional view schematically illustrating the hydrogen permeation diffusion path observation device of the present invention for hydrogen permeation detection of a sample using a hydrogen permeation detection sample holder.

[0047] Figure 2 This is a partially enlarged view showing the hydrogen ion detection device configured in the analysis chamber of a scanning electron microscope within a hydrogen permeation diffusion path observation device.

[0048] Figure 3A This is a schematic cross-sectional view showing a first embodiment of the sample holder.

[0049] Figure 3B It was omitted. Figure 3A A top view of a portion of the sample holder shown.

[0050] Figure 4 It is Figure 3A A schematic cross-sectional view of the disassembled specimen holder is shown.

[0051] Figure 5 This is a block diagram showing the configuration of the control unit in a hydrogen diffusion path observation device.

[0052] Figure 6 This is a block diagram showing the structure of the electron bombardment detachment from the overall control unit.

[0053] Figure 7 This is a schematic diagram illustrating the relationship between electron beam scanning and two-dimensional measurement of ESD images.

[0054] Figure 8 This is a flowchart of measuring two-dimensional ESD images by scanning with an electron beam.

[0055] Figure 9 This is a schematic cross-sectional view showing the second embodiment of the sample holder.

[0056] Figure 10 yes Figure 9 A partially enlarged cross-sectional view of the main part of the specimen holder.

[0057] Figure 11 It shows the use in sequence. Figure 9 The flowchart shows the preparation process for hydrogen permeation detection of the sample by using a hydrogen permeation diffusion path observation device on the sample holder.

[0058] Figure 12 This is a schematic cross-sectional view of the third embodiment of the sample holder.

[0059] Figure 13 This is a schematic cross-sectional view of the fourth embodiment of the sample holder. Detailed Implementation

[0060] The present invention will now be described in detail with reference to the accompanying drawings based on several embodiments. However, these embodiments are merely examples for illustrating the present invention and should be understood not as limiting the scope of protection of the present invention.

[0061] First, the overall structure of the hydrogen permeation diffusion path observation device will be described using the hydrogen permeation detection sample holder (hereinafter referred to as the sample holder) 30 according to the present invention, which is used to perform hydrogen permeation detection of the sample 17 held in the sample holder 30.

[0062] Figure 1 This schematically illustrates the hydrogen diffusion path observation device 10. Figure 2 The hydrogen ion detection device 20 is shown in the analysis chamber 11 of the scanning electron microscope 15 within the hydrogen permeation diffusion path observation device 10. The hydrogen permeation diffusion path observation device 10 mainly includes the scanning electron microscope 15, the hydrogen ion detection device 20, and a sample holder 30 arranged in an accessible manner within the analysis chamber 11 of the scanning electron microscope 15, with a sample 17 disposed on the upper part of the sample holder 30.

[0063] The scanning electron microscope 15 includes an analysis chamber 11 and an electron source 16 that irradiates an electron beam onto a sample 17 placed on a sample holder 30 within the analysis chamber 11. The analysis chamber 11 is equipped with a secondary electron detector 18 that detects secondary electrons generated by the electron beam 16a irradiating the sample 17 from the electron source 16; and a hydrogen ion detection device 20 that detects hydrogen ions generated by the irradiated electron beam 16a. A control unit 50 for controlling the hydrogen ion detection device 20 is connected to the hydrogen ion detection device 20. Furthermore, the analysis chamber 11 includes a sample temperature measuring unit 26 for measuring the temperature of the sample 17. The sample temperature measuring unit 26 uses a thermocouple or the like, and its wires are connected to a wire lead-out port 11a located on the outer wall of the analysis chamber 11. The analysis chamber 11 may also be equipped with a mass spectrometer 29 for analyzing residual elements. The mass spectrometer 29 is, for example, a quadrupole mass spectrometer. The scanning electron microscope 15 requires evacuating the analysis chamber 11 to a vacuum level sufficient for obtaining a SEM image, for example, 1.0 × 10⁻⁶. -7 Ultra-high vacuum below Pa. Therefore, a vacuum exhaust unit 27 is connected to the analysis chamber 11, and a vacuum is achieved through the vacuum exhaust unit 27. The vacuum exhaust unit 27 is equipped with a vacuum pump (not shown) such as a turbomolecular pump, as well as gate valves, vacuum gauges, etc.

[0064] The sample holder 30 includes a bias voltage supply wiring 19, a differential exhaust pipe 35, and a supply pipe 13 and an exhaust pipe 14 connected to the back side of the sample 17 for supplying and discharging electrolyte. The sample holder 30 is configured to allow entry and exit between the inlet / outlet and the exterior of the hydrogen permeation diffusion path observation device 10. The inlet / outlet is located at an appropriate location, such as the side wall or bottom surface of the analysis chamber 11. The sample holder 30 is positioned on the sample stage 24 within the analysis chamber 11, and the position of the sample stage 24 is adjusted by the sample position adjustment part 25. The sample 17 is placed on the upper surface of the sample holder 30 and, together with the sample holder 30, is positioned directly below the electron source 16 within the analysis chamber 11 of the scanning electron microscope 15. Details of the structure of the sample holder 30 will be described later.

[0065] Figure 2 Details of the hydrogen ion detection device 20 are shown. The hydrogen ion detection device 20 detects hydrogen ions generated on the surface of the sample 17 using the ESD method, scanning the sample 17 with the electron beam 16a of the electron source 16. Figure 7 As shown), a two-dimensional image based on hydrogen ions is obtained. This is referred to as an ESD image or ESD map. In this embodiment, the hydrogen ion detection device 20 includes: a collection mechanism 21 for collecting hydrogen ions generated by electron beam scanning from the surface of the sample 17; an ion energy decomposition unit 22 for removing hydrogen ions and other ions; and an ion detection unit 23 for detecting hydrogen ions that have passed through the ion energy decomposition unit 22.

[0066] The collection mechanism 21 of the hydrogen ion detection device 20 is disposed near the surface of the sample 17 for efficient collection of detached ions. The illustrated collection mechanism 21 is, for example, composed of a mesh of metal wires and is a grating-structured lens. Hydrogen ions collected by the collection mechanism 21 are incident on the ion energy decomposition section 22, where they are sorted and incident on the ion detector 23. The ion energy decomposition section 22 is composed of a cap-shaped metal electrode such that the ion detector 23 is not directly opposite the sample 17. Electrodes including cylindrical and conical shapes can be used as the ion energy decomposition section 22. By applying an appropriate positive voltage to the cylindrical electrode, the ion energy decomposition section 22 guides only the ions of the target gas, specifically the hydrogen ions of this invention, into the ion detector 23 through an electric field, thus removing the light and electrons generated by irradiating the sample 17 with the electron beam 16a. The ion detector 23 can be, for example, a ceramic secondary electron multiplier tube.

[0067] The hydrogen permeation diffusion path observation device 10 of this embodiment is configured as described above, and the sample holder 30 is disposed in the analysis chamber 11 of the scanning electron microscope 15 constituting the device in a freely movable manner. Hereinafter, refer to... Figure 3A , Figure 3B and Figure 4 A detailed description of an example of the construction of the sample holder 30 is provided below. As shown in the figures, the sample holder 30 is configured to include: a holder body 31; a sealing member 32 disposed on the surface of the holder body 31; and a pressing plate 33 placed on the surface of the holder body 31 in a manner that clamps the sample 17 from above.

[0068] (Structure of the main body 31 of the support frame)

[0069] Because minimizing hydrogen release is required, the support body 31 is constructed from ultra-high vacuum materials such as stainless steel, copper, glass, and Teflon (registered trademark), and is integrally formed into a roughly cylindrical shape using materials capable of withstanding baking treatments above 100°C, for example, around 120°C. The support body 31 has a hollow portion within its peripheral wall that serves as an electrolyte inlet chamber 31b. The top plate of the electrolyte inlet chamber 31b has an opening 31c on the surface of the support body 31 (also referred to as the upper surface), corresponding to the measurement area 17a of the sample 17, opening at its center.

[0070] (Structure of electrolyte introduction chamber 31b)

[0071] In the electrolyte inlet chamber 31b, during the processing time, the electrolyte 34 is filled to the opening 31c. At an appropriate depth within the electrolyte inlet chamber 31b, a counter electrode 36 of a bias voltage supply wiring 19 (described later) is positioned, which is connected from the support body 31 to an external DC power supply. An insulating and corrosion-resistant coating 31d is applied to the inner surface of the electrolyte inlet chamber 31b, which is divided within the support body 31, to prevent corrosion by the electrolyte 34. This insulating and corrosion-resistant coating 31d is also made of a material capable of withstanding baking treatments above 100°C. Since the insulating and corrosion-resistant coating 31d is not exposed to a vacuum, a Teflon coating can be used, for example.

[0072] (Structure of the sealing component 32)

[0073] An opening 31c is formed on the surface, i.e., the upper surface, of the support body 31. Two sealing members 32 are concentrically arranged and double-sided around the opening 31c, spaced at a predetermined interval. The area 32c between the double sealing members 32 is configured with a substantially fixed width. The double sealing members 32 are, for example, elastomeric seals, specifically, configured as double O-rings of different diameters to surround the opening 31c formed on the upper surface of the support body 31. Relative to the measurement area 17a of the sample 17, the inner O-ring 32b is a ring with a slightly smaller diameter, while the outer O-ring 32a is a ring with a larger diameter, spaced at a predetermined interval from the inner O-ring.

[0074] The two O-rings 32a and 32b are respectively made of known vacuum O-rings, such as fluororubber from Viton or Kalrez. However, both O-rings 32a and 32b must be made of materials capable of withstanding baking treatment at temperatures above 100°C. Of these two O-rings 32a and 32b, the outer O-ring 32a is made of a material with high insulation properties, for example, with an inner diameter of 11 mm. The inner O-ring 32b has an inner diameter of, for example, 4 mm, and since it comes into contact with the electrolyte 34, it is made of a material with high insulation and corrosion resistance. In the illustrated case, each O-ring 32a and 32b of the sealing component 32 is positioned by being embedded in a locking groove provided on the surface of the support body 31. The two engagement grooves are respectively formed to be wider than the diameter of the O-rings 32a and 32b, and each O-ring 32a and 32b is embedded in these engagement grooves.

[0075] (Settings for Sample 17)

[0076] Before measurement, sample 17 is placed on the surface (upper surface) of sample holder 30 outside the hydrogen permeation diffusion path observation device 10. Here, sample 17 is a thin plate made of materials such as metal, Si substrate, steel or stainless steel, with a thickness of about 100 to 300 μm. Its diameter is at least the size of the outer sealing member 32a of the double sealing members 32. The sample 17 is set on the upper surface of sample holder 30 to block the sealing members 32. The hollow part of sample holder 30 is separated from the analysis chamber 11 by sample 17, and sample 17 functions as a diaphragm separating the analysis chamber 11 from the hollow part. In the case of the size of the O-ring 32a (inner diameter 11 mm), the thickness of sample 17 is, for example, about 100 μm to 1 mm, and the size of sample 17 is, for example, a diameter of 16 mm.

[0077] (Structure of differential exhaust pipe 35)

[0078] An opening 35a is provided on the upper surface of the support body 31 between the outer sealing member 32a and the inner sealing member 32b. A differential vent pipe 35, communicating with the outside through the opening 35a and the peripheral wall of the support body 31, is provided. Before measurement, the electrolyte inlet chamber 31b is evacuated to, for example, 10 ppm through the differential vent pipe 35. -4 Vacuum level at Pa.

[0079] (Structure of supply pipe 13 and discharge pipe 14)

[0080] On the peripheral wall of the electrolyte inlet chamber 31b of the sample holder 30, an electrolyte supply pipe 13 and an electrolyte discharge pipe 14 are provided at two locations on one side, one above the other. During processing, electrolyte 34 is introduced through the supply pipe 13, and the processed electrolyte 34 is discharged through the discharge pipe 14 for circulation. The supply pipe 13 and the discharge pipe 14 are able to withstand the above-mentioned baking treatment and are made of materials that are not corroded by electrolyte 34, such as heat-resistant Teflon (registered trademark) tubing, and are electrically insulated relative to the holder body 31.

[0081] (Based on the structure of pressure plate 33)

[0082] The sample 17 is covered from above by the pressing plate 33 of the sample holder 30. The pressing plate 33 is made of a plate-shaped conductive material, such as stainless steel (SUS), and is made of the same material as the holder body 31, capable of withstanding baking treatments above 100°C. The pressing plate 33 has an area with the same shape as the cylindrical sample holder 30 or a slightly larger diameter, and has a central through-hole 33a with an opening area approximately corresponding to the measurement area 17a of the sample 17. When the sample 17 is placed on the sample holder 30, the through-hole 33a of the pressing plate 33 is located directly above the measurement area 17a on the sample surface and is concentrically positioned corresponding to the opening 31c of the electrolyte inlet chamber 31b in the holder body 31. The pressing plate 33 is connected to one side of the bias voltage supply wiring 19a. Thus, it functions as a bias voltage application electrode during the electrolysis of the electrolyte 34 supplied to the electrolyte inlet chamber 31b of the holder body 31. With the sample 17 clamped between the pressing plate 33 and its surface, the support body 31 is electrically and hermetically pressed together with the insulating sleeve 31a and fixed by screws 39 or the like. The insulating sleeve 31a can be made of materials such as Macor (registered trademark).

[0083] (Structure of the counter electrode 36)

[0084] For the pressing plate 33, which serves as the electrode for applying the bias voltage, a counter electrode 36 is disposed within the electrolyte inlet chamber 31b of the support body 31, and is connected to the wiring 19b on the + side of the bias voltage supply wiring 19. Pt or similar materials can be used as the material for the counter electrode 36. Here, the counter electrode 36 is actually as follows: Figure 4 As shown in the exploded view, the cover component 37 is fixedly held relative to the opening of the support body 31. The cover component 37 is installed from the lower end of the support body via an ultra-high vacuum seal 38, such as a metal gasket, in a way that allows for airtight assembly and disassembly. The wiring 19b on the positive side of the counter electrode 36 passes through the cover component 37 on an insulated basis and is connected to a DC power supply that supplies the bias voltage. In this way, by connecting the pressing plate 33, which serves as the bias application electrode, to the counter electrode 36 using the bias voltage supply wiring 19, a bias voltage is applied, thereby electrolyzing the electrolyte 34 supplied into the hollow portion 31b to generate hydrogen ions. During electrolysis, bubbles may sometimes be generated in the electrolyte 34, but since the bubbles are discharged to the outside along with the used electrolyte 34 through the drain pipe 14, the electrolysis is not hindered by the bubbles.

[0085] For electrolysis, the electrolyte 34 is, for example, a 0.5M NaCl + 0.04M NH4SCN aqueous solution (2% NaCl + 3g / L NH4SCN), at room temperature with an inductance of 1mA / cm. 2A constant current hydrogen filling was performed at a current density of 6 A / m. Alternatively, as electrolyte 34, a 3% NaCl aqueous solution (0.75M NaCl) + 3 g / L NH4SCN was used at a current density of 6 A / m. 2 The current density is then determined. Alternatively, as electrolyte 34, a 3% NaCl aqueous solution (0.75M NaCl) + 3g / L NH4SCN is used at a current density of 6A / m. 2 The current density is adjusted. The type of electrolyte 34 and the electrolysis conditions can be appropriately selected to correspond to the structure of sample 17. Here, as an electrolyte 34 using heavy water, i.e., a heavy aqueous solution instead of an aqueous solution, deuterium can be produced without producing hydrogen.

[0086] In the sample holder 30 of the first embodiment, the sample 17 is configured to be vacuum-sealed by a pressing plate 33 and double sealing components 32a, 32b. Electrolyte 34, filling the electrolyte inlet chamber 31b, is electrolyzed to generate hydrogen ions. The generated hydrogen ions are attracted by the pressing plate 33, which is biased towards the applied side, and introduced into the sample 17. These hydrogen ions diffuse inside the sample 17, aggregate, and reach the surface of the sample 17, from which hydrogen ions emerge. That is, hydrogen permeates from the back side of the sample 17 to the surface, but hydrogen ions are generated by irradiating the hydrogen reaching the surface of the sample 17 with an electron beam 16a. By irradiating the generated hydrogen ions with the electron beam 16a, the hydrogen ions are detached from the sample 17 by electron bombardment depletion (ESD), captured by the collection mechanism 21, and thus detected by the hydrogen ion detection device 20.

[0087] Next, the methods for obtaining SEM and ESD images will be explained.

[0088] The control unit 50 acquires an SEM image of secondary electrons generated from the sample 17 by scanning an electron beam 16a irradiated from an electron source 16, and uses electron bombardment removal (ESD) of the electron beam to hydrogen ionize hydrogen atoms emerging from point defects in the interior and surface of the sample 17, and acquires an ESD image of hydrogen ions synchronously with the scanning of the electron beam.

[0089] Here, ESD is the phenomenon where electrons erupt from the material and collide with hydrogen atoms resting on the surface. The electrons in the hydrogen atoms become excited or are stripped away, causing the hydrogen atoms to ionize. Consequently, the hydrogen atoms detach from their surface-bound state and become debonded. An ESD image is obtained by photographing these detached hydrogen ions. Then, the control unit 50 obtains the positional information of the hydrogen ions detected by synchronizing the SEM image and the ESD image of the sample 17, enabling the detection of the location of point defects in the sample 17.

[0090] Next, the configuration and operation of the control unit 50 of the hydrogen permeation diffusion path measuring device 10 will be explained in more detail. Figure 5 and Figure 6 The block diagram shows the configuration of the control unit 50 and the electron bombardment separation integral control unit 52. Figure 7 The relationship between the scanning of electron source 16 and the two-dimensional measurement of the ESD image is shown. For example... Figure 5 As shown, the control unit 50 is configured to include an overall electron microscope control unit 51 for controlling the scanning electron microscope 15 and an overall electron bombardment separation control unit 52 for acquiring ESD images. In addition to the overall electron microscope control unit 51, the control unit 50 also includes a secondary electron detection unit 53 for acquiring scanning electron microscope (SEM) images of the sample 17, an electron optical system control unit 54, an image processing unit 55 for SEM, a high-voltage stabilized power supply 56, an input device 57, a display 58, and a storage device 59. The secondary electron detection unit 53, the electron optical system control unit 54, the image processing unit 55 for SEM, the high-voltage stabilized power supply 56, and the storage device 59 are controlled by the overall electron microscope control unit 51. The output of the secondary electron detector 18, located in the analysis chamber 11 of the scanning electron microscope 15, is input to the secondary electron detection unit 53.

[0091] Electron bombardment is separated from the overall control unit 52 to control the acquisition of ESD images, such as... Figure 6 As shown, the system comprises a two-dimensional multi-channel calibrator 60, a pulse counter 61, a synchronization control unit 62, a rearrangement unit 63 for rearranging the measurement signals in a two-dimensional plane, and a microprocessor 72. The output of the hydrogen ion detection device 20, located in the analysis chamber 11, is input to the pulse counter 61 via the electron impact ion detection unit 67, whose output 67a is fed into the electron impact ion control unit 52. Scanning signals are input from the electron-optical system control unit 54 to the electron impact ion control unit 52, and control is performed synchronously with the SEM image. Furthermore, a display 65 and a storage device 66 are connected to the electron impact ion control unit 52.

[0092] The microprocessor 72 can also be a microcontroller or other microcomputer, personal computer, or FPGA (Field-Programmable Gate Array).

[0093] like Figure 5 The scanning signal input from the electron-optical system control unit 54 to the electron bombardment separation control unit 52 is shown as follows: Figure 6The vertical scan signal 62a from the synchronization control unit 62 is output to the first deflection coil 16b of the electron source 16. The horizontal scan signal 62b from the synchronization control unit 62 is output to the second deflection coil 16c of the electron source 16. The scan position-related information 62c from the synchronization control unit 62 is output to the microprocessor 72. The hydrogen ion count signal 61a output from the pulse counting unit 61 is output to the microprocessor 72 as the hydrogen ion count signal for each scan position. The ESD image generated by the microprocessor 72 is output to the display 65 via the input / output interface (I / O) 72a and to the storage device 66 via the input / output interface (I / O) 72b.

[0094] Next, the operation of the electron bombardment detaching from the overall control unit 52 will be explained.

[0095] like Figure 7 As shown, the electron beam 16a generated from the electron source 16 passes through the first deflection coil 16b and the second deflection coil 16c, thereby being scanned in a direction perpendicular to the horizontal direction and irradiating the sample 17 in two dimensions.

[0096] As by Figure 7 The clock signal of the vertical scan signal 62a of the digital signal generated by the synchronization control unit 62 is converted into a sawtooth wave by the digital-to-analog converter (DAC) 62d and applied to the first deflection coil 16b of the electronic source 16. Similarly, the clock signal of the horizontal scan signal 62b, which is a digital signal, is converted into a sawtooth wave by the digital-to-analog converter (DAC) 62e and applied to the second deflection coil 16c of the electronic source 16.

[0097] Control is initiated by a single-pulse shooting timing signal (hereinafter referred to as the ST signal), causing a total of 2048 pulses to be generated for the vertical scan signal (vertical clock). During the pulse width of one pulse of the vertical scan signal, a total of 2048 pulses of horizontal pixel signal (horizontal clock) are output. This generates a two-dimensional scan of approximately 4.19 million pixels, consisting of 2048 rows × 2048 columns (=4,194,304). In other words, the signal counted by the pulse counting unit 61 synchronizes multiple counters composed of the ST signal, the vertical scan clock signal, and the horizontal scan clock signal, enabling the acquisition of the hydrogen ion count from the ion detector 23 at each scan position.

[0098] The method for obtaining ESD images is explained.

[0099] Figure 8 This is a flowchart of a two-dimensional ESD image obtained through measurement scanning. For example... Figure 8As shown, the acquisition of a two-dimensional ESD image can be performed through the following steps.

[0100] Step 1: Use ion detector 23 to detect hydrogen ions that have escaped from the surface of sample 17.

[0101] Step 2: The pulse counting unit 61 performs quantitative measurement of hydrogen ions detected by the ion detector 23.

[0102] Step 3: By generating Figure 7 The synchronization control unit 62 for the clock signals used for vertical scanning and horizontal scanning, as shown, performs the quantification of hydrogen ions at each measurement point in two dimensions of the sample 17.

[0103] Step 4: Save the stoichiometric values ​​of hydrogen ions at each measurement point of sample 17 in two dimensions as determined in step 3 in the memory of storage device 66.

[0104] Step 5: Based on the clock signals for vertical scanning and horizontal scanning, the ion signals stored in the memory of storage device 66 are rearranged into a two-dimensional image (ESD image).

[0105] Step 6: Display the ESD image obtained in step 5 on the display 65 and save it as image and numerical data in the storage device 66.

[0106] Therefore, an ESD image of the same region as the SEM image is obtained.

[0107] The acquisition of ESD images in steps 1 to 6 above can be performed using software created in a programming environment specifically designed for controlling measurement equipment. Such software can be LabVIEW (registered trademark) manufactured by National Instruments (http: / / www.ni.com / labview / ja / ). The ESD images in steps 1 to 6 above can also be acquired using a two-dimensional multichannel scaler 60 executed within a program created in LabVIEW on the microprocessor 72.

[0108] In the hydrogen permeation diffusion path observation device 10, SEM images can be obtained in the same manner as before. The signal from the secondary electron detector 18 is detected by the secondary electron detection unit 53 of the control unit 50 and displayed on the display 58 by the overall electron microscope control unit 51.

[0109] Based on the hydrogen permeation diffusion path observation device 10, by comparing the secondary electron-based SEM image of sample 17 with the ESD image obtained in step 6 above, it is possible to investigate the correlation between the local structure of the sample 17, for example, made of metal, and hydrogen permeation. For example, as a local structure, the grain size and crystal structure of the metal can be compared with hydrogen permeation, i.e., hydrogen release capacity.

[0110] Here, the spatial resolution of the hydrogen release location essentially depends on the magnification of the scanning electron microscope 15, and therefore can be improved to the same magnification as the scanning electron microscope 15, thus achieving a resolution of less than 50 nm, for example 2-10 nm, i.e., less than 10 nm. The magnification limit of the scanning electron microscope 15 is determined by the vibration cancellation of the scanning electron microscope 15 and its surroundings, as well as the diameter of the electron beam.

[0111] Furthermore, in order to make the detection of hydrogen ions consistent with the limit of secondary electron detection of the scanning electron microscope 15, the difference in flight time between electrons and hydrogen ions becomes a problem, but this can be addressed by slowing down the electron scanning time during the measurement or shortening the distance between the ion detector 23 and the sample 17.

[0112] The sample holder 30 and the hydrogen permeation diffusion path measuring device 10 using the sample holder 30 in this embodiment of the invention are configured as described above, and the hydrogen permeation detection of the sample 17 mounted on the sample holder 30 is performed as follows.

[0113] First, the material used as sample 17 is thinned and mirror-polished on both the surface and back side to produce sample 17. For hydrogen ion detection on the surface of sample 17, the back side of sample 17 needs to be vacuum-vented, for example, by contacting a sealed component 32 made of an elastomeric seal. Furthermore, while holding sample 17 from the sealed component 32, and with pressing plate 33 mounted, pressing plate 33 is brought into contact with the surface of the support body 31 of sample holder 30 via insulating sleeve 31a, for example, by a screw thread connection. Then, supply pipe 13 and discharge pipe 14 for electrolyte 34 are connected to sample holder 30, and wires 19a on the - side and 19b on the + side of bias voltage application wiring 19 are connected to pressing plate 33 and counter electrode 36, respectively. Finally, cover component 37 is mounted on the back side of support body 31.

[0114] From this state onwards, the sample holder 30 carrying the sample 17 is positioned on the sample stage 24 located in the analysis chamber 11 of the scanning electron microscope 15.

[0115] Then, the vacuum in the analysis chamber 11 is evacuated to an ultra-high vacuum through the vacuum exhaust section 27, and differential exhaust is performed on the region 32c between the two O-rings 32a and 32b of the sealing component 32 through the differential exhaust pipe 35.

[0116] Next, the entire analytical chamber 11 and sample holder 30 are baked. This baking process is for degassing in the ultra-high vacuum section, and is carried out, for example, at a temperature of about 120°C for about 24 hours.

[0117] Next, electrolyte 34 is supplied from supply pipe 13 into the hollow portion 31b of the support body 31 disposed on the sample holder 30, and electrolyte 34 is discharged through discharge pipe 14. Thus, electrolyte 34 circulates within the hollow portion 31b.

[0118] Furthermore, by providing a bias voltage between wires 19a and 19b of the bias voltage application wiring 19, a bias voltage is applied within the hollow portion 31b between the pressing plate 33 and the opposing electrode 36, causing the electrolyte 34 present therebetween to be electrolyzed, generating hydrogen ions. These hydrogen ions are attracted toward the pressing plate 33, which serves as the bias voltage application electrode, thereby being introduced into the sample 17, diffusing within the sample 17, and being released from its surface.

[0119] By irradiating the surface of the sample 17 with an electron beam 16a containing hydrogen from an electron source 16, hydrogen ions are ejected from the sample 17 via electron bombardment desorption (ESD). These hydrogen ions are collected by a collection mechanism 21 and detected by a hydrogen ion detection device 20 to obtain an ESD image. Thus, the control unit 50 can investigate the correlation between the local structure of the tissue in the sample 17 and hydrogen permeation by comparing the secondary electron-based SEM image and the ESD image.

[0120] Regarding the hydrogen permeation detection of sample 17, conventional methods use hydrogen gas for hydrogen permeation. However, in this invention, hydrogen is generated through the electrolysis of electrolyte 34, thereby providing electrochemical supplementation for hydrogen permeation of sample 17. Therefore, the amount of hydrogen introduced into sample 17 is increased dramatically, for example, by 100 times. Consequently, during hydrogen permeation detection, the hydrogen signal intensity increases, the measurement time required for measuring the hydrogen permeation diffusion path is shortened, and the signal-to-noise ratio (S / N ratio) is significantly improved. Furthermore, because the amount of hydrogen introduced into sample 17 is increased, hydrogen permeation detection can be performed on samples that could not be detected using conventional methods with hydrogen gas.

[0121] Figure 9 The structure of a second embodiment of the sample holder 40 of the present invention is shown.

[0122] exist Figure 9In this configuration, the sample holder 40 has a container 41 within the hollow portion 31b of the holder body 31, which abuts against the back of the sample 17. The opposing electrode 36 is disposed on the bottom surface of the container 41. Figure 3A and Figure 4 The sample holder 30 shown has different structures.

[0123] The container 41 is open at its upper end 41a, for example, and is made of glass. The upper end 41a of the opening abuts against the back of the sample 17, and an electrolyte inlet chamber 41c for containing the electrolyte 34 is formed inside. At this time, the upper end 41a and the back of the sample 17 are wetted by the electrolyte 34 contained inside and sealed by its surface tension.

[0124] In addition, the bottom surface of container 41 is connected to an elastic member, in Figure 9 The container 41 is supported on the cover plate 37 by a spring member 42 consisting of a helical spring. Thus, while the spring member 42 is compressed, with the cover plate 37 mounted on the back of the support body 31, the upper end 41a of the container 41 is subjected to upward force by the spring member 42, pressing against the back of the sample 17, and tightly adhering through so-called surface tension liquid tightness.

[0125] Here, the diameter of container 41 is chosen to be larger than the diameter of the through hole 33a of pressing plate 33 (e.g., about 4-7 mm). Therefore, as Figure 10 As shown in detail, the upper end 41a of the container 41 abuts against the back of the sample 17 in the area corresponding to the outside of the through hole 33a of the pressing plate 33, thus not applying a load to the sample 17. Furthermore, the upper end 41a of the container 41 can also abut against the back of the sample 17 via an elastomer 41b. The elastomer 41b can be attached to the upper end 41a of the container 41 by means of an adhesive or the like.

[0126] A supply tube 13 and a discharge tube 14, as well as a + side wiring 19b of a bias voltage application electrode wiring 19, are connected to the container 41. In this case, the environment around the container 41 is not a vacuum, so the supply tube 13 and the discharge tube 14 can be plastic tubes. In addition, the wiring 19b can be made of coated wire, reducing costs.

[0127] Electrolyte 34 is supplied to the electrolyte inlet chamber 41c, which is divided by the inner surface of the O-ring 32a on the back of the container 41, the sample 17, and the inner side of the sealing component 32. Therefore, the volume of electrolyte 34 supplied to the electrolyte inlet chamber 41c is small. Thus, compared with... Figure 3A and Figure 4 Compared to the sample holder 30 shown, it is also suitable for the following situations: the hydrogen permeation of the sample holder 40 is low, and the hydrogen supply is sufficient even from a small amount of hydrogen supplied from the electrolyte 34. When the container 41 is a glass beaker, compared to... Figure 3A and Figure 4 Compared to the sample holder 30 shown, the insulating and corrosion-resistant coating 31d of the hollow portion 31b is not required. When the container 41 is made of metal, to prevent corrosion of the container 41 caused by contact with the electrolyte 34, only the inner surface of the container 41 needs to be coated with an insulating and corrosion-resistant coating, thus reducing costs.

[0128] The sample holder 40, based on this structure, is similar to the sample holder 30 described above, and is disposed on the sample stage 24 within the analysis chamber 11 of the hydrogen permeation diffusion path measuring device 10, according to... Figure 11 The flowchart shown outlines the preparation work from the replacement of sample 17 to the measurement of hydrogen permeation detection of sample 17.

[0129] That is, in Figure 11 In step ST1, the material of sample 17 is first thinned, and the surface and back are mirror-polished to produce sample 17. In step ST2, sample 17 is placed on the surface of the support body 31 of sample holder 40 on a double sealing member 32. With the sample 17 clamped from the sealing member 32 and a pressing plate 33 placed on it, the pressing plate 33 is brought into contact with the surface of the support body 31 of sample holder 40 via an insulating sleeve 31a, for example, by a screw threaded connection. In this state, the area 32c between the two O-rings 32a and 32b of the sealing member 32 is differentially vented via a differential vent pipe 35 to fix sample 17 and perform vacuum sealing.

[0130] Next, in step ST3, the container 41 and the counter electrode 36 are mounted on the surface of the cover member 37 of the sample holder 40 via the spring member 42. Then, in step ST4, the container 41 is brought into contact with the sample 17, and the cover member 37 is mounted on the back of the holder body 31 of the sample holder 40.

[0131] Next, in step ST5, the sample holder 40 is positioned on the sample stage 24 of the analysis chamber 11 of the scanning electron microscope 15. In step ST6, differential venting is performed on the area 32c between the double sealing components 32 through the differential vent pipe 35. Then, in step ST7, the interior of the analysis chamber 11 and the entire sample holder 40 are baked. In step ST8, electrolyte 34 is supplied into the container 41 through the supply pipe 13 and discharged through the discharge pipe 14. Thus, the container 41 is filled with electrolyte, completing the preparation for hydrogen permeation detection.

[0132] From this state, similar to the case of sample holder 30, when a bias voltage is applied between the pressing plate 33 and the opposing electrode 36 via the bias voltage application wiring 19 to generate hydrogen ions through electrolysis, the hydrogen ions are attracted toward the pressing plate 33, which functions as the bias voltage application electrode. Thus, the hydrogen ions are introduced into the interior of the sample 17, diffuse, and hydrogen is released from the sample 17. When this released hydrogen is irradiated with an electron beam 16a, the hydrogen ions detach from the sample 17 via ESD. By detecting these hydrogen ions, an ESD image is obtained. By comparing this ESD image with a secondary electron-based SEM image, the correlation between the local structure of the tissue in the sample 17 and hydrogen permeation can be investigated.

[0133] Figure 12 The structure of a third embodiment of the sample holder 44 of the present invention is shown. This sample holder 44 is related to... Figure 3A and Figure 4 Compared to the sample holder 30 shown, the hollow portion 31b of the holder body 31 is omitted, and the holder body 31 is made of a conductive material. The wiring 19b on the + side of the bias voltage application wiring 19 is connected to the holder body 31, thereby functioning as the counter electrode 36. Here, in the holder body 31, it is preferable to apply an insulating and corrosion-resistant coating to the surface in contact with the electrolyte 34.

[0134] In this configuration, the electrolyte inlet chamber S for supplying electrolyte 34 is formed by the surface of the support body 31, the back of the sample 17, and the O-ring 32b inside the double-sealed component 32. Furthermore, the supply pipe 13 and discharge pipe 14 for electrolyte 34 open onto the inner region of the O-ring 32b on the surface of the support body 31. Thus, electrolyte 34 is supplied from the outside into the electrolyte inlet chamber S via the supply pipe 13 and discharged to the outside via the discharge pipe 14.

[0135] Furthermore, by applying a bias voltage to the pressure plate 33 and the support body 31 through the wires 19a and 19b of the bias voltage application wiring 19, the electrolyte 34 in the electrolyte introduction chamber S is electrolyzed to generate hydrogen. This hydrogen is introduced into the sample 17 and diffuses, releasing from its surface.

[0136] Thus, with Figure 3A and Figure 4 Similarly, in the sample holder 30 shown, hydrogen ions are irradiated from the sample 17 by an electron beam 16a irradiated with hydrogen from an electron source 16. The hydrogen ions are then released from the sample 17 via ESD, collected by a collection mechanism 21, and detected by a hydrogen ion detection device 20 to obtain an ESD image. Thus, the control unit 50 can investigate the correlation between the local structure of the tissue in the sample 17 and hydrogen permeation by comparing the secondary electron-based SEM image and the ESD image.

[0137] In this case, with Figure 9Compared to the case of container 41 in the sample holder 40 shown, the capacity of the electrolyte inlet chamber S supplied with electrolyte 34 is smaller, thus further reducing hydrogen permeation, making it suitable for samples 17 where a small amount of hydrogen supply from electrolyte 34 is sufficient. Furthermore, the holder body 41 can be miniaturized, and by being made of conductive material, it also functions as a counter electrode, thus simplifying the overall structure.

[0138] Figure 13 The structure of the sample holder 45 according to the fourth embodiment of the present invention is shown. The sample holder 45 is related to... Figure 12 The sample holder 44 shown omits the supply pipe 13 and the discharge pipe 14. In this case, the electrolyte 34 is sealed inside the electrolyte inlet chamber S when the sample 17 is placed. The electrolyte 34 does not circulate during electrolysis, but the hydrogen permeation is further reduced, making it suitable for samples 17 where a small amount of hydrogen from the electrolyte 34 in the electrolyte inlet chamber S is sufficient. Here, in the holder body 31, it is preferable to apply an insulating and corrosion-resistant coating to the surface in contact with the electrolyte 34.

[0139] Furthermore, since the supply pipe 13 and the discharge pipe 14 are not required, the miniaturization of the support body 31 is further promoted, the structure is simplified, and thus the component cost and assembly cost are reduced. In addition, in the sample holder 45, when the electrolyte 34 is sealed in the electrolyte inlet chamber S, the sample holder 45 cannot be baked because of the opening of the diaphragm of the analysis chamber 11 of the scanning electron microscope 15. However, the sample holder 45 can be used for samples 17 that do not require baking of the sample holder 45. For example, in the case of a scanning electron microscope 15 equipped with a pre-venting chamber and capable of replacing so-called load-locking type samples, a sample holder 45 that does not require baking can be used.

[0140] This invention can be implemented in various ways without departing from its spirit. For example, in the above-described embodiments, the sample 17 is made of a conductive material such as steel or stainless steel, but it is not limited thereto and can obviously also be made of an insulating material.

[0141] Symbol Explanation

[0142] 10: Hydrogen permeation diffusion path observation device; 11: Analysis chamber; 11a: Lead wire outlet; 13: Supply pipe; 14: Discharge pipe; 15: Scanning electron microscope; 16: Electron source; 17: Sample; 17a: Measurement area; 18: Secondary electron detector; 19: Bias voltage supply wiring; 19a: Wiring on the - side; 19b: Wiring on the + side; 20: Hydrogen ion detection device; 21: Collection mechanism; 22: Ion energy decomposition unit; 23: Ion detector; 24: Sample stage; 25: Sample position adjustment 26: Sample temperature measuring section; 27: Vacuum exhaust section; 29: Mass spectrometer; 30, 40, 44, 45: Sample holder; 31: Holder body; 31a: Insulating sleeve; 31b: Electrolyte inlet chamber (hollow section); 31c: Opening; 31d: Insulating and corrosion-resistant coating; 32: Double sealing component; 32a, 32b: Ring; 32c: Area between the double sealing components; 33: Press plate (bias voltage application electrode); 33a: Through hole; 34: Electrolyte; 35: Differential exhaust pipe; 3 5a: Opening; 36: Opposing electrode; 37: Cover component; 38: Ultra-high vacuum seal; 39: Screw; 41: Container; 41a: Upper end of the container; 41b: Elastomer; 41c: Electrolyte inlet chamber; 42: Spring component; 50: Control unit; 51: Overall control unit for electron microscope; 52: Overall control unit for electron bombardment separation; 53: Secondary electron detection unit; 54: Electron optical system control unit; 55: Image processing unit for SEM; 56: High-voltage stabilization power supply; 57: Input device; 58: 65: Display; 59, 66: Storage device; 60: Two-dimensional multi-channel calibrator; 61: Pulse counting unit; 61a: Hydrogen ion measurement signal; 62: Synchronization control unit; 62a: Vertical scan signal; 62b: Horizontal scan signal; 62c: Information related to scan position; 62d, 62e: Digital-to-analog converter; 63: Rearrangement unit for rearranging measurement signals to a two-dimensional plane; 67: Electron bombardment ion detection unit; 72: Microprocessor; 72a, 72b: Input / output interface; S: Electrolyte introduction chamber.

Claims

1. A sample holder for hydrogen permeation detection, characterized in that, include: The main support is mounted on a scanning electron microscope and holds the sample used to detect hydrogen ions generated by electron beam irradiation; The electrolyte inlet chamber has an opening that is open relative to the measurement area of ​​the sample; The pressing plate has a through hole corresponding to the measurement area of ​​the sample, and presses the sample from the electron source side of the scanning electron microscope around the through hole, thereby clamping the sample airtightly between it and the support body. A double sealing component is disposed between the surface of the support body and the sample in such a way that it surrounds the measurement area of ​​the sample. A differential exhaust pipe opens between the double sealing components on the surface of the support body and exhausts gas from the opening; as well as Electrodes, including biasing electrodes and counter electrodes used in electrolysis. The pressing plate, which serves as the bias application electrode, is made of a conductive material. The counter electrode is disposed in the electrolyte inlet chamber, or the sample holder is made of a conductive material to serve as the counter electrode. A voltage is applied between the bias electrode and the counter electrode to introduce hydrogen from the electrolyte into the sample.

2. The sample holder for hydrogen permeation detection according to claim 1, wherein, The electrolyte inlet chamber includes an opening on the surface of the support body and a hollow portion disposed inside the support body from the opening, wherein the counter electrode is disposed within the hollow portion.

3. The sample holder for hydrogen permeation detection according to claim 2, characterized in that, An insulating and corrosion-resistant coating is applied to the inner surface of the hollow portion.

4. The sample holder for hydrogen permeation detection according to claim 1, characterized in that, The electrolyte inlet chamber is divided by the back of the sample, the inner sealing component of the double sealing component, and the surface of the support body.

5. The sample holder for hydrogen permeation detection according to claim 4, characterized in that, The opposing electrode is connected to the support body.

6. The sample holder for hydrogen permeation detection according to any one of claims 1 to 5, characterized in that, It has a supply pipe for supplying electrolyte to the electrolyte inlet chamber and a discharge pipe for discharging the electrolyte.

7. The sample holder for hydrogen permeation detection according to claim 6, characterized in that, During electrolysis, the electrolyte is supplied through the supply pipe and the used electrolyte is discharged from the discharge pipe.

8. The sample holder for hydrogen permeation detection according to claim 1, characterized in that, The support body, the opposing electrode, the electrolyte inlet chamber, and the sealing components are all made of materials that can be baked.

9. The sample holder for hydrogen permeation detection according to claim 1, characterized in that, The support body is made of a conductive material and functions as the opposing electrode, and is electrically insulated relative to the pressing plate.

10. The sample holder for hydrogen permeation detection according to claim 2, characterized in that, The hollow section has an opening on the back side of the support body, and the opening on the back side is sealed by the cover component via an ultra-high vacuum seal. The container, supported by an elastic member on the surface side of the cover component, forms the electrolyte inlet chamber. Inside the sealed hollow section, the upper end of the container opening abuts against the back of the sample by the force of the elastic component.

11. The sample holder for hydrogen permeation detection according to claim 4, characterized in that, The bubbles generated during electrolysis are discharged from the region between the double-sealed components through the opening via the differential exhaust pipe.

12. A device for observing hydrogen permeation diffusion paths, characterized in that, include: A scanning electron microscope is used in the analysis chamber to detect secondary electrons generated when a sample is irradiated with an electron beam. A hydrogen permeation detection sample holder is mounted on the scanning electron microscope and holds the sample, the sample having a measurement area for detecting hydrogen ions generated by irradiation by the electron beam. A hydrogen ion detection device detects hydrogen ions generated by an electron beam irradiating hydrogen, which escapes from the back side of a sample held in a sample holder to the surface. The sample holder comprises: Support body; The electrolyte inlet chamber has an opening that is open relative to the measurement area of ​​the sample; The pressing plate has through holes corresponding to the measurement area of ​​the sample, and presses the sample from the electron source side of the scanning electron microscope around the through holes, thereby clamping the sample airtightly between the plate and the support body. A double-sealed component is disposed between the surface of the support body and the sample in a manner that surrounds the measurement area of ​​the sample. A differential exhaust pipe opens between the double sealing components on the surface of the support body and exhausts gas from the opening; as well as Electrodes, including biasing electrodes and counter electrodes used in electrolysis. The pressing plate, which serves as the bias application electrode, is made of a conductive material. The counter electrode is disposed in the electrolyte inlet chamber, or the main body of the support is made of conductive material to serve as the counter electrode. A voltage is applied between the bias electrode and the counter electrode to introduce hydrogen from the electrolyte into the sample. In this manner, an electron beam is irradiated with hydrogen emanating from the back side of the sample toward the surface, thereby measuring the hydrogen ions generated by the electron beam using the hydrogen ion detection device.

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