JP2022020448A - Sample for detecting hydrogen permeation, and manufacturing method thereof - Google Patents

Abstract

To provide a sample for detecting hydrogen permeation that is obtained by causing a support member to impart desired rigidity to a thin-film sample body having low rigidity that cannot stand on its own, and a manufacturing method thereof.SOLUTION: A sample 45 for detecting hydrogen permeation is composed of a plate-shaped support member 46 having predetermined rigidity and hydrogen permeability, and a thin-film sample body 47 arranged on the surface of the support member 46.SELECTED DRAWING: Figure 1

Description

In the present invention, hydrogen atoms transmitted from the back surface of a plate-shaped sample or hydrogen atoms ejected from the inside of the material of the sample are excited by scanning electrons of a scanning electron microscope, and hydrogen ions are desorbed by an electron transition-induced desorption method. It relates to a sample for detecting hydrogen permeation, which is separated and obtains an ESD image of the desorbed hydrogen ions in synchronization with scanning of an electron beam of a scanning electron microscope.

Conventionally, for such hydrogen permeation detection, for example, the hydrogen permeation diffusion path observation device disclosed in Patent Document 1 is used. The hydrogen permeation / diffusion path observation device includes a scanning electron microscope, an analysis room, a diaphragm-type vacuum vessel on which the sample is mounted, and a hydrogen pipe connected to the diaphragm-type vacuum vessel to supply hydrogen to the back surface of the sample. I have. The sample serves as a diaphragm that separates the analysis chamber from the hollow portion (hereinafter referred to as the hydrogen chamber) that houses hydrogen in the diaphragm-type vacuum vessel. Hydrogen that springs out from the surface of the sample is excited by an electron beam that acquires a scanning electron microscope image (hereinafter referred to as SEM image) to become hydrogen ions and is desorbed from the surface (ESD (Electron)). Stimulated Desorption) mechanism), the ESD image by this hydrogen ion is acquired together with the SEM image.

Japanese Unexamined Patent Publication No. 2017-187457

By the way, in such a hydrogen permeation / diffusion path observation device, as described above, since the sample itself also functions as a diaphragm separating the analysis chamber and the hydrogen chamber, it functions as a certain degree of rigidity and a vacuum seal. is necessary.
On the other hand, when the sample is formed into a thin thin film that cannot stand on its own, it is difficult to maintain its shape due to its low rigidity, and it cannot function as the above-mentioned diaphragm. It ends up. Therefore, for such a sample, it is practically impossible to detect hydrogen permeation with the sample alone.

Further, if a local insulating region exists on the surface of the thin film sample that is so thin that the sample alone cannot stand on its own, the insulating region is locally negatively charged and so-called charge-up occurs. As a result, in the charge-up generation area of the insulating region, it becomes difficult for electrons to approach during electron irradiation, so that the electron irradiation density on the entire surface of the sample becomes non-uniform.

On the other hand, in a general electron microscope, a method of irradiating the surface of an insulator or plastic that is easily charged up with positive ions to neutralize it, or a surface when measuring the insulator or plastic itself. A method of coating a thin carbon or metal thin film on the surface to suppress the occurrence of charge-up is known.

However, when measuring secondary electrons, disposing a thin film of carbon or metal on the surface of the sample is effective for suppressing the occurrence of charge-up, but when measuring hydrogen ions, Since there is a risk of hindering the permeation of hydrogen ions, the use of such a thin film of carbon or metal is not always effective for the permeation of hydrogen ions.

In view of the above points, the present invention is a sample for hydrogen permeation detection in which a thin-film sample body having a low rigidity that cannot stand on its own is provided with a desired rigidity and a function as a vacuum seal by a support member. The first purpose is to provide the above, and the second purpose is to provide the manufacturing method thereof.

The first purpose is to use a sample for detecting hydrogen permeation, which comprises a plate-shaped support member having predetermined rigidity and hydrogen permeability and a thin-film sample body disposed on the surface of the support member. Achieved.

In the above configuration, the sample for detecting hydrogen permeation is preferably a thin film to the extent that the sample body cannot stand on its own.
The support member is preferably composed of either palladium, vanadium, niobium, tantalum, titanium, zirconium, silver or an alloy thereof.
It is preferable that the front surface and / or the back surface of the support member is mirror-polished. This support member is preferably formed uniformly with respect to hydrogen permeability and is composed of crystal grains or single crystals that are larger than the structural distribution of the sample body, for example, one digit or more larger, or have a structural distribution of the sample body. On the other hand, it may be composed of small crystals, for example, one digit or more smaller. The sample body is preferably locally provided with an insulating portion, or is entirely composed of an insulating material, and a conductive thin film having hydrogen permeability is disposed on the surface of the sample body.

The second object is achieved by a method for producing a sample for detecting hydrogen permeation, in which a sample body is formed on the surface of a support member by a chemical deposition method or a physical deposition method.

In the above configuration, the sample body is preferably formed by either a vacuum vapor deposition method, an electron beam vapor deposition method, or a sputtering method.
A conductive thin film is formed on the surface of the sample body, preferably by thin film deposition. The conductive thin film is preferably formed by a vacuum vapor deposition method, an electron beam vapor deposition method, or a sputtering method, or may be formed by a sputtering method to the extent that the surface of the sample is not damaged.

According to the present invention, it is possible to provide a sample for detecting hydrogen permeation and a method for producing the same, in which a support member imparts desired rigidity to a thin-film sample body having a low rigidity that cannot be self-supporting. can.

It is an enlarged sectional view which shows the structure of the 1st Embodiment of a sample for hydrogen permeation detection by this invention. It is a figure which shows the structural example of the hydrogen permeation diffusion path observation apparatus for performing hydrogen permeation detection with respect to the sample of FIG. 1 schematically. FIG. 2 is a partially enlarged view showing a hydrogen ion detection unit and a mounting structure of a sample holder in the analysis chamber of the hydrogen permeation / diffusion path observation device of FIG. It is a block diagram which shows the structure of the control part of the hydrogen permeation diffusion path observation apparatus of FIG. It is a block diagram which shows the structure of the electron shock desorption whole control part of the hydrogen permeation diffusion path observation apparatus of FIG. It is a schematic diagram which shows the relationship between the scanning of an electron beam and the two-dimensional measurement of an ESD image. It is a flow diagram which measures a two-dimensional ESD image by scanning an electron beam. It is a figure which shows an example of the crystal structure which has a large crystal grain as a support member which supports the sample of FIG. It is a figure which shows the crystal structure of FIG. 8 further enlarged. It is an enlarged sectional view which shows the structure of the 2nd Embodiment of a sample for hydrogen permeation detection by this invention.

Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.
FIG. 1 shows the configuration of a first embodiment of a sample (hereinafter referred to as a sample) for detecting hydrogen permeation according to the present invention.

In FIG. 1, the sample 45 is composed of a support member 46 and a sample body 47 arranged on the surface of the support member 46. The sample body 47 is a thin film layer made of a conductive material or an insulating material. In the case of illustration, insulating regions 48a and 48b are arranged in a part of the sample body 47. The insulating regions 48a and 48b are not limited to one location, and a plurality of insulating regions 48a and 48b are arranged. The support member 46 is made of a material having predetermined rigidity and hydrogen permeability, and is formed in a plate-like flat shape.
The predetermined rigidity means that the shape of the sample body 47 can be maintained in the hydrogen permeation / diffusion path observation device 10 described later, and the hollow portion 12a (referred to as a hydrogen chamber) of the analysis chamber 11 of the scanning electron microscope 15 and the sample holder 12. ) And the rigidity that can function as a diaphragm. As the material having such rigidity and hydrogen permeability, metal materials such as palladium, vanadium, niobium, tantalum, titanium, zirconium, silver and alloys thereof are suitable. Examples of the alloy include an alloy of palladium and silver.

Further, the support member 46 is appropriately selected so as to have a predetermined rigidity according to the type of the sample main body 47 arranged on the surface of the support member 46, for example, in the range of the thickness of about 100 μm to 1000 μm. The size of the support member 46 is arbitrary, but the diameter may be, for example, about 5 mm to 20 mm.

Further, the support member 46 is preferably mirror-polished on its front surface and / or back surface. Since the surface of the support member 46 is mirror-polished, when hydrogen atoms are desorbed from the surface of the support member 46, it is not affected by the surface shape of the support member 46, and accurate hydrogen permeation detection is performed. At the same time, the back surface of the support member 46 is mirror-polished to improve the adhesion and secure the vacuum sealing property as a partitioning membrane.

The above-mentioned material of the support member 46 has predetermined rigidity, can function as the diaphragm, and has high hydrogen permeability. It has been practically used as a so-called hydrogen filter, and has hydrogen permeability, so that the support member has a hydrogen permeability. It can be used as 46 and does not interfere with the permeation of hydrogen ions during hydrogen permeation detection.

Further, the support member 46 is uniformly formed with respect to hydrogen permeability. According to this configuration, the sample body 47 is arranged on the surface of the support member 46 uniformly formed with respect to hydrogen permeability, so that hydrogen permeation detection by electron transition induction of the sample body 47 can be detected by hydrogen in the support member 46. It can be performed uniformly and accurately over the entire surface of the sample body 47 without being affected by the permeability.

Specifically, the support member 46 is a crystal grain or a single crystal that is sufficiently large with respect to the region where hydrogen permeation detection of the sample body 47 should be performed, that is, with respect to the structural distribution or the field of view of the scanning electron microscope 15. It is composed of. The crystal grains or single crystals of the support member 46 may be composed of crystal grains or single crystals that are an order of magnitude larger than the structural distribution of the sample body 47. For example, when the structural distribution of the sample body 47 is smaller than 30 μm, the support member 46 may be composed of crystal grains or single crystals having a size of 300 μm or more. As a result, the region where the hydrogen permeation detection of the sample body 47 should be performed, that is, the structural distribution is contained in only one crystal of the support member 46, and the hydrogen permeation detection by the electron transition induction of the sample body 47 can be detected by the support member 46. It can be performed uniformly and accurately over the entire surface of the sample body 47 without being affected by the crystal boundary of the sample body 47.

On the other hand, the support member 46 is sufficiently small with respect to the region where hydrogen permeation detection of the sample body 47 should be detected, that is, the structural distribution, or with respect to the field of view of the scanning electron microscope 15, for example, a large number of crystals smaller by an order of magnitude or more. It may be composed of crystals. For example, if the structural distribution of the sample body 47 is 30 μm, the particle size of the microcrystals may be 3 μm or less. As a result, the region where hydrogen permeation detection of the sample body 47 should be performed corresponds to a large number of microcrystals of the support member 46, and the hydrogen permeation becomes almost uniform as a whole. Hydrogen permeation detection by transition induction can be performed uniformly and accurately over the entire surface of the sample body 47 without being affected by the crystal boundary of the support member 46.

The sample body 47 is made of a material such as metal or Si. Here, the sample body 47 is subjected to a chemical vapor deposition method (CVD method) or a physical vapor deposition method (PVD method) on the surface of the support member 46 according to the embodiment of the sample manufacturing method for detecting hydrogen permeation according to the present invention. A film can be formed. As the physical deposition method, a coating film is formed on the surface of the support member 46 by any vapor deposition method such as a vapor deposition method, for example, a vacuum vapor deposition method, an electron beam vapor deposition method, a sputtering method, or the like. As a result, the sample body 47 can be reliably and uniformly formed on the surface of the support member 46 by, for example, a vapor deposition method, particularly a vacuum vapor deposition method, an electron beam vapor deposition method, or a sputtering method.

The sample body 47 is a thin film having a low rigidity that cannot stand on its own. Therefore, when the sample body 47 is arranged on the surface of the support member 46, it is necessary to reinforce the sample body 47 with the support member 46 so as to have a shape-retaining property so that the sample body 47 can stand on its own. It can function as a diaphragm separating the hydrogen chamber 12a. The sample body 47 may or may not have a hydrogen diffusion preventing effect or a hydrogen diffusion suppressing effect. Further, the sample body 47 also includes a thin film having a hydrogen diffusion preventing effect or a hydrogen diffusion suppressing effect partially.

The sample 45 for detecting hydrogen permeation according to the embodiment of the present invention is configured as described above, and a case of detecting hydrogen permeation of this sample 45 will be described. FIG. 2 schematically shows a configuration example of the hydrogen permeation / diffusion path observation device 10 for detecting hydrogen permeation with respect to the sample 45, and FIG. 3 shows hydrogen ion detection in the analysis chamber 11 of the hydrogen permeation / diffusion path observation device 10. It is a partially enlarged view which shows the structure of a part 20 and the mounting structure of a sample holder 12.

As shown in FIG. 2, the hydrogen permeation diffusion path observation device 10 includes a scanning electron microscope 15, and in the analysis chamber 11 of the scanning electron microscope 15, electrons are generated in a sample 45 arranged above the sample holder 12. An electron source 16 for irradiating a line is provided. Further, in the analysis chamber 11, a secondary electron detector 18 for detecting secondary electrons generated by the electron beam 16a irradiated on the sample 45 in the analysis chamber 11 and hydrogen generated by the electron beam 16a emitted from the electron source 16 are provided. A hydrogen ion detection unit 20 for detecting ions, a control unit 50 for controlling the hydrogen ion detection unit 20, and a gas supply unit 19 for supplying hydrogen to a hydrogen pipe 14 connected to the back surface side of the sample 45 are provided. There is.

The sample 45 may be heated by a sample heating unit (not shown) in the analysis chamber 11. Further, the sample 45 is fixed to a sample mounting portion (not shown) of the sample holder 12 or adhered by welding or the like. As shown in FIG. 3, the sample 45 is arranged in the analysis chamber 11 of the scanning electron microscope 15 together with the sample holder 12. As a result, the hydrogen chamber 12a of the sample holder 12 and the analysis chamber 11 are partitioned by the sample 45, so that the sample 45 functions as a diaphragm separating the analysis chamber 11 and the hydrogen chamber 12a.

The hydrogen ion detection unit 20 has a collection mechanism 21 that collects hydrogen ions generated from the surface of the sample 45, an ion energy decomposition unit 22 that removes non-hydrogen ions, and an ion that detects hydrogen ions that have passed through the ion energy decomposition unit 22. It consists of a detection unit 23 and.

In the sample holder 12, hydrogen supplied from the hydrogen gas supply unit 19 and existing inside the hydrogen chamber 12a of the sample holder 12 is in contact with the back surface side of the sample 45, and is from the back surface side of the support member 46 of the sample 45. Introduced inside. This hydrogen diffuses inside the support member 46 of the sample 45 and the sample body 47, reaches the front side of the sample 45, that is, the surface of the sample body 47, and is released from the surface of the sample body 47. That is, hydrogen and deuterium permeate from the back surface side of the sample 45 to the front surface. By irradiating the hydrogen reaching the surface of the sample body 47 with an electron beam 16a, hydrogen ions are desorbed from the sample body 47 by electron shock desorption (ESD), and the hydrogen ions are focused by the collection mechanism 21. It is detected by the hydrogen ion detection unit 20.

The hydrogen ion detection unit 20 detects hydrogen ions generated on the surface of the sample body 47 by the ESD method. The two-dimensional image of hydrogen ions detected by scanning the electron beam 16a is also called an ESD image or ESD map.

A collection mechanism 21 for efficiently collecting desorbed ions is arranged in the vicinity of the surface side of the sample 45. The illustrated collection mechanism 21 is made of, for example, a mesh of metal wires, and is a lens having a grid structure. Ions of the target gas collected by the collection mechanism 21, for example, hydrogen ions, are incident on the hydrogen ion detection unit 20. In the ion energy decomposition unit 22, for example, hydrogen ions are selected and incident on the ion detector 23.

The ion energy decomposition unit 22 is composed of a metal electrode having a lid shape so that the ion detector 23 does not directly face the sample 45. The ion energy decomposition unit 22 can use an electrode having a shape including a cylinder or a cone. Generated by applying an appropriate positive voltage to the cylindrical electrode of the ion energy decomposition unit 22, guiding only the ions of the target gas, for example, hydrogen ions, to the ion detector 23 by an electric field, and irradiating the sample 45 with an electron beam 16a. Can remove light and electrons. As the ion detector 23, for example, a seratron or a secondary electron multiplier tube can be used.

The control unit 50 acquires an SEM image of secondary electrons generated from the sample 45 by scanning the electron beam 16a emitted from the electron source 16, and generates hydrogen atoms ejected from point defects on the inside and the surface of the sample 45. Hydrogen ionization is performed by electron shock desorption (ESD) of the electron beam, and an ESD image of the hydrogen ion is acquired in synchronization with the scanning of the electron beam. Here, in ESD, when an irradiated electron hits a hydrogen atom that springs out from a material and stays on the surface, the electron in the hydrogen atom becomes an excited state or is stripped off to ionize the hydrogen atom. As a result, the ESD image is obtained by imaging the desorbed hydrogen ions in a phenomenon in which the desorbed hydrogen ions are desorbed from the state of being bonded to the surface to the anti-bonded state. Then, the control unit 50 can obtain the position information of the detected hydrogen ion by synchronizing the SEM image and the ESD image of the sample 45, and can detect the position of the point defect of the sample 45.

Next, the configuration and operation of the control unit 50 of the hydrogen ion detection device 10 will be described in more detail. The block diagrams of FIGS. 4 and 5 show the configurations of the control unit 50 and the electron shock desorption overall control unit 52, respectively, and FIG. 6 is a schematic diagram showing the relationship between the scanning of the electron source 16 and the two-dimensional measurement of the ESD image. Is.

As shown in FIG. 4, the control unit 50 includes an electron microscope overall control unit 51 that controls the scanning electron microscope 15, and an electron shock desorption overall control unit 52 that acquires an ESD image. .. In addition to the electron microscope overall control unit 51, the control unit 50 includes a secondary electron detection unit 53 for acquiring a scanning electron microscope image (SEM image) of the sample 45, an electron optical system control unit 54, and an SEM. It is composed of an image calculation unit 55 for use, a high voltage stabilized power supply 56, an input device 57, a display 58, a storage device 59, and the like. The electron microscope overall control unit 51 controls the secondary electron detection unit 53, the electron optical system control unit 54, the image calculation unit 55 for SEM, the high voltage stabilized power supply 56, and the storage device 59. The output of the secondary electron detector 18 arranged in the analysis chamber 11 of the scanning electron microscope 15 is input to the secondary electron detection unit 53.

Next, the electron shock desorption overall control unit 52 will be described. As shown in FIG. 5, the electronic shock desorption overall control unit 52 that controls the acquisition of the ESD image includes a two-dimensional multi-channel scaler 60, a pulse coefficient unit 61, a synchronization control unit 62, and a two-dimensional measurement signal. It is composed of a rearrangement unit 63 on a flat surface, a microprocessor 72, and the like.
The output of the hydrogen ion detection unit 20 arranged in the analysis chamber 11 is input to the pulse counting unit 61 via the electron shock desorption ion detection unit 67. A scanning signal is input from the electron optical system control unit 54 to the electron shock desorption overall control unit 52, and is controlled in synchronization with the SEM image. Further, a display 65 and a storage device 66 are connected to the electronic shock desorption overall control unit 52.

The microprocessor 72 may be a microcomputer such as a microcontroller, a personal computer, or an FPGA (Field-Programmable Gate Array) which is a gate array programmable in the field.

As shown in FIG. 4, the scanning signal output from the electron optical system control unit 54 to the electron shock desorption overall control unit 52 is an electron source as a vertical scanning signal 62a via the synchronization control unit 62 as shown in FIG. It is output to the first deflection coil 16b of 16. The horizontal scanning signal 62b from the synchronization control unit 62 is output to the second deflection coil 16c of the electron source 16. The information 62c regarding the scanning position 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 a hydrogen ion count signal at each scanning position.

The ESD image generated by the microprocessor 72 is output to the display 65 via the input / output interface (I / O) 72a, and is output to the storage device 66 via the input / output interface (I / O) 72b.

Next, the operation of the electronic shock desorption overall control unit 52 will be described.
As shown in FIG. 6, the electron beam 16a generated from the electron source 16 passes through the first deflection coil 16b and the second deflection coil 16c, and is scanned in the horizontal and vertical directions to the sample 45. The dimension is illuminated.

The clock signal of the vertical scanning signal 62a, which is a digital signal generated by the synchronization control unit 62 shown in FIG. 6, is converted into a saw wave by the digital-to-analog converter (DAC) 62d, and the first deflection coil 16b of the electron source 16 is used. Is applied to. Similarly, the clock signal of the horizontal scanning signal 62b, which is a digital signal, is converted into a saw wave by the digital-to-analog converter (DAC) 62e and applied to the second deflection coil 16c of the electron source 16.

Control is started so that a total of 2048 pulses is generated in the vertical scanning signal (Vertical clock) by the shooting timing signal (Shoot timing, hereinafter referred to as ST signal) of one pulse. During the period of the pulse width of one pulse of the vertical scanning signal, a total of 2048 pulses of the horizontal pixel signal (Horizontal clock) are output. As a result, a two-dimensional scan of about 4.19 million pixels of 2048 rows × 2048 columns (= 4194304) is generated. That is, the signal counted by the pulse counting unit 61 is from the ion detector 23 at each scanning position by synchronizing a plurality of counters including an ST signal, a clock signal for vertical scanning, and a clock signal for horizontal scanning. It can be obtained as a count number of hydrogen ions.

Subsequently, a method of acquiring an ESD image will be described.
FIG. 7 is a flow chart for measuring a two-dimensional ESD image by scanning. As shown in FIG. 7, acquisition of a two-dimensional ESD image can be performed by the following steps.
Step 1: Hydrogen ions desorbed from the surface of the sample 45 are detected by the ion detector 23.
Step 2: Quantitative measurement of hydrogen ions detected by the ion detector 23 is performed by the pulse counting unit 61.
Step 3: The synchronization control unit 62 that generates the clock signal for vertical scanning and the clock signal for horizontal scanning shown in FIG. 6 counts hydrogen ions at each of the two-dimensional measurement points of the sample 45.
Step 4: The count number of hydrogen ions at each two-dimensional measurement point of the sample 45 measured in step 3 is stored in the memory of the storage device 66.
Step 5: The ion signal stored in the memory of the storage device 66 is rearranged as a two-dimensional image (ESD image) based on the clock signal for vertical scanning and the clock signal for horizontal scanning.
Step 6: The ESD image acquired in step 5 is displayed on the display 65, and the image and numerical data are stored in the storage device 66.
As a result, an ESD image in the same region as the SEM image is acquired.

The acquisition of the ESD image in steps 1 to 6 can be executed by software created in a program production environment specialized for measuring instrument control. As such software, LabVIEW® (http://www.ni.com/labview/ja/) manufactured by National Instruments Co., Ltd. can be used. The ESD images of steps 1 to 6 can be acquired by the two-dimensional multi-channel scaler 60 executed by the program created by LabVIEW in the microprocessor 72.

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

In this way, according to the hydrogen permeation / diffusion path observation device 10, by comparing the SEM image by secondary electrons with respect to the sample 45 and the ESD image acquired in step 6, for example, the structure of the sample body 47 made of metal, for example, It is possible to investigate the relationship between local structure and hydrogen permeation. For example, as a local structure, it is possible to compare the crystal grain size of a metal and its crystal structure with hydrogen permeation, that is, hydrogen release ability.

Here, since the spatial resolution of the hydrogen emission position essentially depends on the magnification of the scanning electron microscope 15, it can be improved to the same level as the magnification of the scanning electron microscope 15, so that it is 50 nm or less, for example, 2 to 10 nm, that is, A resolution of 10 nm or less can be obtained. The limit of the magnification of the scanning electron microscope 15 is determined by the vibration elimination and the electron beam diameter of the scanning electron microscope 15 and its surroundings.

Further, in order to match the detection of hydrogen ions 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 the time of electron scanning during measurement is delayed. This can be done by doing so or by shortening the distance between the ion detector 23 and the sample 45.

In this way, in the sample 45, the sample main body 47 made of a thin film having a low rigidity that cannot stand alone is arranged on the support member 46, so that the sample body 46 is reinforced by the support member 46. It has a predetermined rigidity and surely functions as a diaphragm separating the analysis chamber 11 and the hydrogen chamber 12a of the scanning electron microscope 15. Therefore, even if the sample body 47 is made of a thin film that cannot stand on its own, hydrogen permeation can be detected.

Here, as shown by an arrow A in FIG. 1, the hydrogen that has diffused the support member 46 having uniform and high hydrogen permeability has a hydrogen diffusion preventing effect or a hydrogen diffusion suppressing effect with respect to the sample body 47 of the sample 45. In some cases, it does not permeate the sample body 47, or permeates only a very small amount.
On the other hand, as shown by the arrow B, the hydrogen that has diffused the support member 46 having uniform and high hydrogen permeability has no hydrogen diffusion preventing effect or hydrogen diffusion suppressing effect with respect to the sample body 47 of the sample 45. In this case, the sample body 47 is transmitted with a high transmittance. Therefore, since the support member 46 is uniform and has high hydrogen permeability, the surface hydrogen distribution that permeates the sample body 47 reflects the hydrogen permeation characteristics of the sample body 47.

As described above, in the sample 45 for detecting hydrogen permeation of the present invention, even if the sample body 47 is a thin film having a rigidity so low that it cannot stand on its own, it is a plate having predetermined rigidity and hydrogen permeability. Since it is supported and reinforced by the support member 46, the shape of the sample body 47 can be reliably maintained, and the scanning electron microscope 15 in the hydrogen permeation diffusion path observation device 10 is analyzed for hydrogen permeation detection. It can sufficiently function as a diaphragm separating the chamber 11 and the hydrogen chamber 12a. Therefore, even if the sample body 47 is a thin film having a low rigidity that cannot stand on its own, hydrogen permeation detection of the sample body 47 can be reliably performed.

An example of a prototype of the support member 46 constituting the sample 45 will be described.
In this prototype, the support member 46 was made of a palladium polycrystalline thin plate, and the front and back surfaces of the palladium polycrystalline plate were polished and heat-treated. Polishing and heat treatment of the front surface and the back surface of the palladium thin plate may be performed not only once but repeatedly.
The surface of such a prototype of the support member 46 was imaged using a scanning electron microscope 15 for structural analysis. The SEM image is shown in FIG. 8, and the EBSD image by the Electron Back Scattered Diffraction (hereinafter referred to as EBSD) is shown in FIG.
In FIGS. 8 and 9, the crystal structure of the support member 46 is represented, and each crystal grain is 300 μm or more, and a uniform hydrogen supply substrate can be obtained in the field of view of the scanning electron microscope 15. The three markers near the center of the image in FIG. 8 are engraved with an ion beam or a laser to specify the location.

FIG. 10 shows a second embodiment of a sample for detecting hydrogen permeation according to the present invention. In the sample 45A of FIG. 10, the support member 46 is the same as that of the sample 45 shown in FIG. 1, and the insulating regions 48a and 48b due to oxides and the like are locally arranged on the surface region of the sample body 47. However, in the second embodiment, the conductive thin film 49 is further arranged over the entire surface including the insulating regions 48a and 48b of the sample body 47.

The insulating regions 48a and 48b may be made of the same insulating material, respectively, and may be, for example, an insulating film such as an oxide film or a nitride film formed on the surface of the sample body 47, and particularly depend on the manufacturing method. do not do. The insulating regions 48a and 48b are not limited to the insulating film formed on the surface of the sample body 47, but may be an insulating film formed so as to be embedded in the surface from the inside.

The conductive thin film 49 is made of a conductive material having hydrogen permeability, preferably a material that does not cause mutual diffusion with the surface of the sample body 47. By not causing mutual diffusion, even if the conductive thin film 49 is arranged, it does not affect and change the surface state of the sample body 47.

Here, as the conductive material having hydrogen permeability, metal materials such as palladium, vanadium, niobium, tantalum, titanium, zirconium, silver and alloys thereof are suitable. Examples of the alloy include an alloy of palladium and silver. These materials have high hydrogen permeability and have been put into practical use as so-called hydrogen filters, and do not interfere with the permeation of hydrogen ions when detecting hydrogen permeation.

Here, the conductive thin film 49 is formed by a chemical deposition method (CVD method) or a physical deposition method (PVD method) on the surface of the sample body 47 by the method for producing the sample 45A for detecting hydrogen permeation according to the present invention. Can be filmed. As a physical deposition method, a vapor deposition method such as a vacuum vapor deposition method, an electron beam vapor deposition method, or a sputtering method is used to form a coating film on the surface of the sample body 47. As a result, the conductive thin film 49 is uniformly formed on the surface of the sample body 47 with an accurate film thickness by any method of vapor deposition, particularly vacuum vapor deposition, electron beam vapor deposition, or sputtering.
In the case of the sputtering method, the surface condition of the sample body 47 is changed by forming the conductive thin film 49 to the extent that the surface of the sample body 47 is not damaged by particles or the like colliding with the surface of the sample body 47 by sputtering. Accurate hydrogen permeation detection can be performed without changing.

Further, the conductive thin film 49 has a uniform film thickness as a whole, and the film thickness is, for example, about the same as the spatial resolution of the scanning electron microscope 15 used for detecting hydrogen permeation, for example, 50 nm or less, preferably 50 nm or less. It is selected to be about 10 nm to 20 nm, or several nm to about 10 nm. The conductive thin film 49 is preferably formed so as to have a film thickness of several nm to 10 nm, for example, about 2 nm to 10 nm. If the thickness of the conductive thin film 49 is too thick, the hydrogen permeability is lowered and the hydrogen ions move horizontally in the conductive thin film 49 to lower the resolution. On the other hand, if the film thickness is too thin, it is difficult to form a uniform film thickness.

According to the sample 45A of the second embodiment, as in the case of the sample 45, the sample body 47 is reinforced by the support member 46 to partition the analysis chamber 11 and the hydrogen chamber 12a of the scanning electron microscope 15. Can function as a diaphragm. Further, when hydrogen permeation detection is performed, charge-up does not occur in the insulating regions 48a and 48b due to the presence of the conductive thin film 49, so that the electron density does not decrease in these insulating regions 48a and 48b. , Hydrogen permeation can be reliably detected over the entire sample body 47.

According to the sample 45A of the second embodiment, since the conductive thin film 49 having hydrogen permeability is arranged on the surface of the sample body 47, the sample 45A is subjected to the scanning electrons of the scanning electron microscope 15. Even if electrons try to accumulate in the insulating regions 48a and 48b of the sample body 47 when excited by electron transition induction to detect hydrogen permeation, they move along the conductive thin film 49, so that the insulating regions 48a, The 48b is charged to prevent the occurrence of so-called charge-up. Therefore, the hydrogen ions excited by the above-mentioned electron transition induction are desorbed without being affected by the charge-up.

Here, since the conductive thin film 49 has hydrogen permeability, hydrogen ions are desorbed without being hindered by the presence of the conductive thin film 49. As a result, by synchronizing the ESD image of the desorbed hydrogen ions with the scanning of the electron beam of the scanning electron microscope 15, the ESD image can be accurately acquired and the permeation detection of the hydrogen ions can be performed with high accuracy.

Since the hydrogen atom detected by the hydrogen permeation detection stores the history of the permeation path up to that point as information, the conductive thin film 49 is made of a hydrogen-permeable material, so that the hydrogen atom is generated. These historical information are not erased when passing through the conductive thin film 49, and it is possible to eliminate only the influence of charge-up.

The present invention can be implemented in various forms without departing from the spirit of the present invention. In the above-described embodiment, the sample body 47 of the sample 45 is made of a conductive material such as steel or stainless steel, but the present invention is not limited to this, and the sample body 47 may be made of an insulating material. it is obvious.

Further, in the above-described embodiment, the sample 45A is provided with insulating regions 48a and 48b due to oxides and the like locally disposed on the surface region of the sample body 47, but the sample 45A is not limited to this. The entire surface of the sample body 47 may be provided with an insulating region, or the sample body 47 may itself be made of an insulating material.

10: Hydrogen permeation / diffusion path measuring device, 11: Analysis chamber, 12: Sample holder, 12a: Hollow part (hydrogen chamber), 14: Hydrogen piping, 15: Scanning electron microscope, 16: Electron source,
18: Secondary electron detector, 19: Gas supply unit, 20: Hydrogen ion detector, 21: Collection mechanism, 22: Ion energy decomposition unit, 23: Ion detector, 45, 45A: Sample for hydrogen permeation detection , 46: Support member, 47: Sample body, 48a, 48b: Insulation region, 49: Conductive thin film with hydrogen permeability,
50: Control unit, 51: Electron microscope overall control unit, 52: Electron shock desorption overall control unit,
53: Secondary electron detection unit, 54: Electron optics control unit, 55: Image calculation unit for SEM,
56: High voltage regulated power supply, 57: Input device, 58, 65: Display,
59, 66: Storage device, 60: Two-dimensional multi-channel scaler,
61: Pulse counting unit, 61a: Hydrogen ion count signal, 62: Synchronous control unit,
62a: vertical scan signal, 62b: horizontal scan signal, 62c: information about scan position,
62d, 62e: Digital-to-analog converter, 63: Sorting part of measurement signal to two-dimensional plane, 64: Image calculation part for ESD, 67: Electronic shock desorption ion detection part, 72: Microprocessor, 72a, 72b : Input / output interface

Claims (13)

A plate-shaped support member with predetermined rigidity and hydrogen permeability, and
A thin-film sample body disposed on the surface of the support member and
A sample for hydrogen permeation detection. The sample for detecting hydrogen permeation according to claim 1, wherein the sample body is a thin film that cannot stand on its own. The sample for detecting hydrogen permeation according to claim 1 or 2, wherein the support member is made of palladium, vanadium, niobium, tantalum, titanium, zirconium, silver or an alloy thereof. The sample for detecting hydrogen permeation according to any one of claims 1 to 3, wherein the support member has a front surface and / or a back surface polished to a mirror surface. The sample for detecting hydrogen permeation according to any one of claims 1 to 4, wherein the support member is uniformly formed with respect to hydrogen permeability. The sample for detecting hydrogen permeation according to claim 5, wherein the support member is composed of crystal grains or single crystals that are larger than the structural distribution of the sample body. The sample for detecting hydrogen permeation according to claim 5, wherein the support member is composed of microcrystals that are smaller than the structural distribution of the sample body. Claim 1 in which the sample body is locally provided with an insulating portion or is entirely composed of an insulating material, and a conductive thin film having hydrogen permeability is disposed on the surface of the sample body. A sample for detecting hydrogen permeation according to any one of 1 to 7. The method for producing a sample for detecting hydrogen permeation according to any one of claims 1 to 8, wherein the sample body is formed on the surface of the support member by a chemical deposition method or a physical deposition method. The method for producing a sample for detecting hydrogen permeation according to claim 9, wherein the sample body is formed by any of a vacuum vapor deposition method, an electron beam vapor deposition method, and a sputtering method. The method for producing a sample for detecting hydrogen permeation according to claim 8, wherein the conductive thin film is formed on the surface of the sample body by vapor deposition. The method for producing a sample for detecting hydrogen permeation according to claim 11, wherein the conductive thin film is formed by a vacuum vapor deposition method or an electron beam vapor deposition method. The method for producing a sample for detecting hydrogen permeation according to claim 11, wherein the conductive thin film is formed by a sputtering method to the extent that the surface of the sample body is not damaged.

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