A preparation method of a transmission electron microscope (TEM) stage for a focused ion beam (FIB) suitable for various materials

Abstract

This invention discloses a method for preparing a transmission electron microscope (TEM) stage for focused ion beam (FIB) applications suitable for various materials, comprising the following steps: preparing a thin slice for stage preparation; processing the thin slice to obtain a circular slice with a diameter of d; cutting the circular slice to obtain two semi-circular slices as stages; marking the sample mounting sites and sample labels on the stage using an ion beam; mounting the sample on the stage and performing the sample preparation process to complete the preparation of the TEM sample; placing the prepared TEM sample into the transmission electron microscope for sample observation and microstructure analysis. This invention is applicable to the preparation of stages made of various materials, effectively solving the various sample requirements for support grids encountered in scientific research. It can effectively solve the need for special stages while reducing the cost of special stages, and can also be used as an emergency measure when conventional stages are temporarily unavailable.

Description

Technical Field

[0001] This invention relates to the field of micro / nano fabrication and material / matter microstructure characterization, specifically a method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials. Background Technology

[0002] Focused ion beam (FIB) plays a crucial role in micro / nano fabrication and the characterization of material / device microstructures. In the analysis of material microstructures, this equipment, along with its accessories, can not only analyze the surface morphology and composition of materials from the nanometer to the micrometer scale; it can also serve as a processing device to prepare high-quality samples for transmission electron microscopy (TEM), thereby enabling comprehensive analysis of the structural information at the atomic scale of materials.

[0003] In fact, the use of FIB (Fiber Ion Beam) to prepare TEM samples has been widely applied in related microstructure research. FIB sample preparation has the following advantages: 1) Point-to-point orientation, suitable for various material preparation needs. FIB can achieve point-to-point extraction, mounting, and processing of samples at the micrometer scale. 2) Wide applicability and small sample volume. FIB preparation of TEM samples has no special requirements on the material or size of raw materials. Even in situations where other conventional sample preparation methods struggle with small single crystal particles, lunar soil, and meteorite samples, FIB can still produce ideal samples. 3) Visualized sample preparation process and high success rate. During the sample processing using an ion beam, the sample preparation process can be simultaneously observed using an electron beam, resulting in a relatively high success rate.

[0004] As mentioned earlier, typical transmission electron microscope (TEM) samples fabricated by FIB are on the micrometer scale (the size of a dust particle), such as 10 μm in length and width. The sample thickness is 1-2 μm, and the final sample thickness needs to be reduced to below 100 nm. The standard stage for transmission electron microscopy (TEM) is a 3 mm diameter ring, therefore the sample or stage diameter must be approximately 3 mm to ensure smooth and safe sample loading and microscopic analysis. The FIB stage referred to below is the stage used for TEM sample loading in FIB. Therefore, commercially available stages are typically semicircles with a 3 mm diameter. To accommodate multiple samples on the same stage, several independent small pillars (usually 3 or 4 pillars) must be machined on the semicircular stage for sample loading. Each pillar is marked with labels such as A, B, C, and D to distinguish samples in different locations, and the manufacturer's logo is engraved on the bottom of the stage.

[0005] Common FIB stages are mainly made of metallic materials such as copper and gold, with copper stages being the most widely used, while molybdenum stages are mainly used for samples containing Cu. Therefore, current FIB stages have the following shortcomings: 1) There are relatively few common stage materials, which cannot meet the needs of component analysis for a variety of samples; 2) Stages made of special materials are expensive, such as molybdenum stages which can cost nearly 200 yuan each. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing a transmission electron microscope stage for focused ion beam (FIB) using various materials, comprising the following steps:

[0007] Step 1) Prepare the thin slices used to prepare the stage;

[0008] Step 2) Process the thin sheet to obtain a circular sheet with a diameter of d;

[0009] Step 3) Cut the circular piece in half to obtain two semicircular pieces, which will serve as a platform;

[0010] Step 4) Use an ion beam to mark the sample mounting positions and sample labels on the stage;

[0011] Step 5) Mount the sample on the stage and perform the sample preparation process to complete the preparation of the TEM sample;

[0012] Step 6) Place the TEM sample into the transmission electron microscope to observe the sample and analyze its microstructure.

[0013] Furthermore, the material of the sheet includes metals, alloys, and non-brittle non-metallic materials;

[0014] The metals include, but are not limited to, copper, aluminum, molybdenum, lead, zinc, iron, cobalt, nickel, tantalum, gold, silver, and platinum.

[0015] Furthermore, the thickness of the sheet ranges from 20 μm to 50 μm.

[0016] Furthermore, processing the thin sheet refers to: punching holes in the thin sheet using a punching device to obtain a circular sheet;

[0017] The drilling equipment includes, but is not limited to, a hole punch and a special sample punch for transmission electron microscopy.

[0018] Furthermore, the method for cutting the circular slice is as follows: use a scalpel with a handle to press and slide along the middle of the circular slice to complete the cutting.

[0019] Furthermore, the steps of marking the sample mounting sites and sample labels on the stage using an ion beam include:

[0020] Roughing is performed using a large ion beam with current i1, followed by finishing using a small ion beam with current i2; i1 > i2.

[0021] Furthermore, the steps for mounting the sample on the stage are as follows:

[0022] Step 1) Make a rectangular notch on the surface of the stage, wherein the length and width of the rectangular notch are not less than 3 times the length and width of the sample to be mounted;

[0023] Step 2) Attach one side of the sample to the stage.

[0024] Furthermore, the steps for mounting the sample on the stage are as follows:

[0025] Step 1) Create a large rectangular notch around the perimeter of the platform;

[0026] Step 2) Create a matrix of smaller gaps in the middle of the large rectangular gap;

[0027] Step 3) Attach the two bottom corners or two sides of the sample to the stage.

[0028] Furthermore, the length of the large rectangular notch is not less than 5 times the sample length, and the width is not less than 1.5 times the sample width; the length of the small matrix notch is the same as the sample length, and the width ranges from [15 μm to 20 μm].

[0029] Furthermore, the sample mounting site and sample label are presented in a hollowed-out form to meet the needs of transmission electron microscopy observation.

[0030] The technical effects of this invention are undeniable, and its beneficial effects are as follows:

[0031] 1) The preparation method of the FIB stage provided by this invention has a relatively simple process flow and practical operation, with high repeatability and success rate. This method can quickly and effectively prepare FIB stages of various materials for TEM sample preparation. Therefore, this method effectively expands the flexibility of self-made FIB grids and is very effective in dealing with scenarios where commercial stages are too expensive and some temporary stage needs exist.

[0032] 2) This invention is applicable to the preparation of stages made of various materials (such as copper, aluminum, molybdenum, lead, zinc, iron, cobalt, nickel, tantalum, gold, silver, platinum, and various alloys), effectively solving the diverse sample requirements for grids encountered in scientific research. This method can effectively address the need for special stages while reducing their cost, and can also be used as an emergency measure when conventional stages are temporarily unavailable. This method provides valuable reference for the diversified self-development and widespread application of multi-material FIB stages. Attached Figure Description

[0033] Figure 1For the corresponding steps (1-3), various metal foils and small round pieces with a diameter of 3mm are punched and cut in half.

[0034] Figure 2 This patent provides a design scheme for the sample mounting position and markings, showing a physical image of a commercial FIB platform and a schematic diagram of sample mounting.

[0035] Figure 3 This is the final physical image of the sample, including the stage and TEM, observed under FIB and transmission electron microscopy. Detailed Implementation

[0036] The present invention will be further described below with reference to embodiments, but it should not be construed that the scope of the present invention is limited to the following embodiments. Various substitutions and modifications made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention should be included within the scope of protection of the present invention.

[0037] Example 1:

[0038] A method for preparing a transmission electron microscope stage suitable for various materials using focused ion beam (FIB) microscopy includes the following steps:

[0039] Step 1) Prepare the thin slices used to prepare the stage;

[0040] Step 2) Process the thin sheet to obtain a circular sheet with a diameter of d;

[0041] Step 3) Cut the circular piece in half to obtain two semicircular pieces, which will serve as a platform;

[0042] Step 4) Use an ion beam to mark the sample mounting positions and sample labels on the stage;

[0043] Step 5) The sample is mounted on the stage and the sample preparation process is performed using a focused ion beam to complete the preparation of the TEM (Transmission Electron Microscope) sample.

[0044] The process of focused ion beam fabrication includes: finding the target location with a scanning electron microscope, depositing a protective layer with an ion beam, then using a high-energy gallium ion beam to dig trenches to form a thin film, cutting the thin film from the substrate, using a nanorobot to extract the thin film and weld it onto a special carrier grid, and using a low-energy ion beam for thinning and surface cleaning.

[0045] Step 6) Place the TEM sample into the transmission electron microscope to observe the sample and analyze its microstructure.

[0046] The material of the sheet includes metals, alloys, and non-brittle non-metallic materials;

[0047] The metals include, but are not limited to, copper, aluminum, molybdenum, lead, zinc, iron, cobalt, nickel, tantalum, gold, silver, and platinum.

[0048] The thickness of the sheet ranges from 20 μm to 50 μm.

[0049] Processing the thin sheet refers to: punching holes in the thin sheet using a punching device to obtain a circular sheet;

[0050] The drilling equipment includes, but is not limited to, a hole punch and a special sample punch for transmission electron microscopy.

[0051] The method for cutting the circular piece is as follows: use a scalpel with a handle to press and slide along the middle of the circular piece to complete the cutting.

[0052] The steps for marking the sample mounting sites and sample labels on the stage using an ion beam include:

[0053] Roughing is performed using a large ion beam with a current of i1, followed by finishing using a small ion beam with a current of i2; i1 > i2. During processing, the beam current can be adjusted appropriately according to the material of the carrier mesh to ensure processing efficiency.

[0054] In this embodiment, i1≥21nA; i2=[2.5nA,21nA].

[0055] The steps for mounting the sample on the stage are as follows:

[0056] 1) A rectangular notch is made on the surface of the stage, and the length and width of the rectangular notch are not less than 3 times the length and width of the sample being mounted;

[0057] 2) Attach one side of the sample to the stage.

[0058] The steps for mounting the sample on the stage are as follows:

[0059] 1) Make a large rectangular notch around the perimeter of the stage; the length of the large rectangular notch shall not be less than 5 times the length of the sample, and the width shall not be less than 1.5 times the width of the sample;

[0060] 2) A matrix of small notches is made in the middle of the large rectangular notch. The length of the matrix of small notches is the same as the length of the sample, and the width ranges from [15 μm to 20 μm].

[0061] 3) Attach the two bottom corners or two sides of the sample to the stage.

[0062] The sample mounting position and sample label are presented in a hollowed-out form to meet the needs of transmission electron microscopy observation.

[0063] Example 2:

[0064] A method for preparing a transmission electron microscope stage suitable for various materials using focused ion beam (FIB) microscopy includes the following steps:

[0065] Step 1) Prepare the thin slices used to prepare the stage;

[0066] Step 2) Process the thin sheet to obtain a circular sheet with a diameter of d;

[0067] Step 3) Cut the circular piece in half to obtain two semicircular pieces, which will serve as a platform;

[0068] Step 4) Use an ion beam to mark the sample mounting positions and sample labels on the stage;

[0069] Step 5) Mount the sample on the stage and perform the TEM sample preparation process to complete the preparation of the TEM sample;

[0070] Step 6) Place the TEM sample into the transmission electron microscope to observe the sample and analyze its microstructure.

[0071] Example 3:

[0072] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as in Example 2, further wherein the material of the thin sheet includes metal, alloy, and non-brittle non-metallic material;

[0073] The metals include, but are not limited to, copper, aluminum, molybdenum, lead, zinc, iron, cobalt, nickel, tantalum, gold, silver, and platinum.

[0074] Example 4:

[0075] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as any one of Examples 2-3, further wherein the thickness of the sheet is in the range of [20 μm, 50 μm].

[0076] Example 5:

[0077] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as any one of Examples 2-4. Further, the processing of the thin film refers to: punching holes in the thin film using a punching device to obtain a circular film.

[0078] The drilling equipment includes, but is not limited to, a hole punch and a special sample punch for transmission electron microscopy.

[0079] Example 6:

[0080] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as any one of Examples 2-5. Further, the method for cutting the disc is as follows: use a scalpel with a handle to press and slide along the middle of the disc to complete the disc cutting.

[0081] Example 7:

[0082] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, with the technical content the same as any one of Examples 2-6, further comprising the step of marking the sample mounting site and sample label on the stage using an ion beam, including:

[0083] Roughing is performed using a large ion beam with current i1, followed by finishing using a small ion beam with current i2; i1 > i2.

[0084] Example 8:

[0085] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, with the same technical content as any one of Examples 2-7. Furthermore, during the processing, the appropriate beam current can be adjusted according to the material of the support grid to ensure processing efficiency.

[0086] Example 9:

[0087] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as any one of Examples 2-8, further wherein i1≥21nA; i2=[2.5nA, 21nA).

[0088] Example 10:

[0089] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as any one of Examples 2-9, further comprising the following steps for mounting the sample on the stage:

[0090] Step 1) Make a rectangular notch on the surface of the stage, wherein the length and width of the rectangular notch are not less than 3 times the length and width of the sample to be mounted;

[0091] Step 2) Attach one side of the sample to the stage.

[0092] Example 11:

[0093] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as any one of Examples 2-10, further comprising the following steps for mounting the sample on the stage:

[0094] Step 1) Create a large rectangular notch around the perimeter of the platform;

[0095] Step 2) Create a matrix of smaller gaps in the middle of the large rectangular gap;

[0096] Step 3) Attach the two bottom corners or two sides of the sample to the stage.

[0097] Example 12:

[0098] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, the technical content of which is the same as any one of Examples 2-11, further wherein the length of the large rectangular notch is not less than 5 times the sample length and the width is not less than 1.5 times the sample width; the length of the small matrix notch is the same as the sample length and the width ranges from [15 μm to 20 μm].

[0099] Example 13:

[0100] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, with the same technical content as any one of Examples 2-12. Furthermore, the sample mounting position and sample label are presented in a hollowed-out form to meet the needs of transmission electron microscope observation.

[0101] Example 14:

[0102] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, comprising the following steps:

[0103] (1) Preparation of metal / alloy foil for the target material stage: Most metal substrates required for the stage can be purchased from professional laboratory consumables. In special requirements or emergency situations, the corresponding metal sheets can also be obtained by mechanical grinding and polishing. In addition, besides metals / alloys, the corresponding stage can also be prepared using sheets of non-brittle non-metallic materials.

[0104] (2) Punching the sample to obtain a small round piece with a diameter of 3mm: It is recommended to use a simple punch (3mm in diameter is sufficient) to complete this process. Alternatively, a special punch for transmission electron microscopy or other punching equipment (such as a precision grinding machine) can be used.

[0105] (3) Cut the 3mm diameter circular piece in half to obtain two similar semicircular pieces: Use a scalpel with a handle to press and slide along the middle of the circular piece to complete the cutting. The resulting semicircular piece is the initial platform. The cutting force required will vary depending on the hardness of the circular piece material. For example, softer metals like copper can be cut easily, while harder metals like molybdenum require more force.

[0106] (4) The stage is finely processed using an ion beam to facilitate sample mounting and marking: The sample mounting positions and markings on the stage are processed using a high-current FIB beam to obtain suitable sample mounting positions. Transmission electron microscope samples can be mounted in two ways: (one side) side mounting and (two corners) middle bridging. The size and shape of the sample mounting positions are designed to reduce the obstruction of the samples after the stage is tilted. At the same time, considering the safety of sample movement and long-term storage, the position of the sample mounting position relative to the substrate is reasonably designed. In addition, if necessary, corresponding markings need to be processed near the sample mounting positions to distinguish different samples.

[0107] (5) Sample mounting and thinning until TEM sample preparation is completed: This process is consistent with the conventional FIB transmission electron microscopy sample preparation procedure and parameters.

[0108] (6) Final transmission electron microscopy observation and analysis of the sample: This process involves placing the final prepared sample into a transmission electron microscope for observation. The parameters, methods and test contents of the electron microscope observation are related to the actual needs of the sample.

[0109] The materials of the metal foil in step (1) include, but are not limited to, copper, aluminum, molybdenum, lead, zinc, iron, cobalt, nickel, tantalum, gold, silver, platinum, etc. Alloy foil can also be customized as needed.

[0110] In step (1), the thickness of the metal foil needs to be controlled between 20-50um. The actual thickness can be determined according to the metal material. Softer metals can be thicker, such as 40um, while harder metals can be thinner, such as 20um.

[0111] The purpose of preparing the 3mm circular slice in step (2) is to meet the standard size of the transmission electron microscope sample so as to ensure that the sample will not slip off after being loaded into the transmission electron microscope sample stage.

[0112] In step (3), the small circular piece is cut into two semi-circular pieces. The purpose is to mount the TEM sample onto the center of the stage so that the sample is placed near the center of the observation area of ​​the stage in the transmission electron microscope, which is convenient for observation by the transmission electron microscope.

[0113] In step (4), the sample mounting position for ion beam processing is usually roughed by a large beam current of 30kV and above 40nA, followed by fine processing of 21nA. The purpose of the large beam current is to shorten the processing time as much as possible while meeting the processing accuracy.

[0114] In step (4), the sample can be mounted on the side or in the middle. The middle mounting method is more recommended, as it can better reduce the problem of sample being blocked by the tilting of the sample stage and solve the problem of sample safety during long-term storage.

[0115] In step (4), considering the sample stage tilting problem that may cause sample occlusion, the backsplash problem during sample thinning process, and the safety problem of long-term sample storage, the size and shape of the sample mounting position need to be specially designed. For specific design parameters, please refer to the attached diagram description section.

[0116] In step (4), the purpose of marking the sample positions is to distinguish different samples when multiple samples are mounted on the same carrier. Roman numerals I, II, III... are recommended for marking, as they are relatively simple and easy to process. Of course, other markings are also acceptable, such as Arabic numerals 1, 2, 3... or A, B, C... etc.

[0117] In step (4), the identification numbers or symbols of the sample position need to be engraved through the entire sample thickness area, that is, presented in a hollow form to meet the needs of transmission electron microscopy observation.

[0118] Example 15:

[0119] A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials, comprising the following steps:

[0120] Step 1: Prepare the metal / alloy sheet for the target material stage

[0121] Various types of metal / alloy foils can be purchased from professional laboratory consumables suppliers, such as... Figure 1 As shown in Figure a, in addition to conventional metal foils such as copper, aluminum, molybdenum, lead, zinc, iron, cobalt, nickel, tantalum, gold, silver, and platinum, foils made of other alloys and non-metallic materials can be customized. Generally, metal foils of different thicknesses can be purchased as needed. In this patent, the thickness of the metal foil 3 is preferably controlled between 20-50 μm; for softer metals, a moderately thicker thickness (e.g., 40 μm) is used, while for harder metals, a thinner thickness (e.g., 20 μm) is acceptable. Because the amount of metal used for the stage is very small (two stages can be made from a small circular piece with a diameter of 3 mm),... Figure 1 (as shown in d), 100mm A 100mm thick metal foil can potentially be used to create over 1000 platforms; therefore, the foil plate size is 100mm. 100mm or smaller is sufficient. Regarding the acquisition of the substrate foil, if commercial purchase is inconvenient or under temporary emergency cleaning conditions, mechanical grinding and polishing can be used to obtain metal sheets, although mechanical grinding and polishing is relatively labor-intensive.

[0122] Step 2: Preparation of 3mm diameter small circular pieces

[0123] Transmission electron microscope (TEM) stages require standard samples to be 3mm in diameter discs; samples that are too large cannot be placed, while those that are too small risk falling. Therefore, this patent describes the fabrication of the stage based on 3mm diameter discs. Specifically, a metal foil plate is punched with a 3mm diameter punch to obtain small 3mm diameter discs. Figure 1 As shown in b and 1c. Compared to the exorbitant price of professional transmission electron microscope (TEM) punches, which can easily cost tens of thousands of yuan, the hole punch, priced at only a few dozen yuan, appears to be exceptionally cost-effective. However, compared to punches, the 3mm discs prepared by the hole punch exhibit relatively noticeable burrs and, in some cases, slight bending deformation of the metal discs. This burr phenomenon hardly affects the use of the FIB stage, and if the burrs are too obvious, they can be lightly sanded off with sandpaper (around 2000 grit is sufficient). For slight bending of small discs, it can often be corrected by clamping and pressing them together with two glass plates.

[0124] Step 3: Cut the small round piece in half to obtain a semi-circular thin slice.

[0125] Referring to the semi-circular design of commercial FIB stages, the stage also uses a 3mm diameter semi-circular sheet. This is because with a semi-circular stage, the sample is placed close to the center of the transmission electron microscope (TEM) stage, allowing for a larger tilt angle and range of motion, which is highly beneficial for subsequent microstructure studies. Furthermore, the semi-circular stage size is perfectly suited for placement on the TEM stage without falling off. Therefore, in this step, the 3mm diameter disc is cut along its center to form two semi-circular sheets, as shown below. Figure 1 As shown in d. It is recommended to use a scalpel with a handle for cutting, as the blade is relatively sharp and hard, making it easier to cut thin metal sheets. It is generally not recommended to use scissors to cut the circular sheet, as this can easily cause the two semicircular ends to be subjected to large shearing forces and produce severe bending deformation. If the final semicircular sheet has slight warping, it can be corrected by the pressing correction method in step (3).

[0126] Step 4: Design and fabrication of TEM sample mounting sites and markers

[0127] The semi-circular sheet obtained before this step can be considered the substrate of the FIB stage, while this step is the core of stage design and sample mounting. This step includes the design and fabrication of the sample mounting position and markings. The following will be combined with the appendix... Figure 2 A detailed explanation will be provided.

[0128] Figure 2 Image a shows a commercial (copper) stage. Four protruding pillars can be seen, corresponding to the letters A, B, C, and D at their bases. These pillars are the mounting positions for TEM samples, and these letters, while marking the pillars, also identify the samples. Figure 2Figure b shows a schematic diagram of the sample mounting positions on this commercial carrier network. Generally, TEM samples can be mounted in two ways: side mounting (one-sided bonding) and center mounting (two-point bonding). These two methods each have their own characteristics, which will not be discussed in detail here. Similarly, two similar TEM sample mounting positions are also provided. Considering the effects of backsplashing during sample thinning, the safety of sample preservation and transfer, and the need for multiple sample labeling, the sample mounting positions and markings for transmission electron microscopy have been meticulously designed. Figure 2 c), the specific explanation is as follows:

[0129] Method 1: Side mounting, with only one side of the sample bonded to the stage. For example... Figure 2 As shown in the left-side view (d), a rectangular notch was created on the surface for side mounting. To minimize sample obstruction during transmission electron microscopy observation due to sample tilting, the notch size must be at least three times the length and width of the sample to be mounted. For example, if the dimensions of the sample to be mounted are 10 μm... If the notch size is 5µm, then the notch size is no less than 30µm. 15um, but in practice, the notch at the sample mounting location is generally no less than 30um. The 20µm depth effectively avoids the stage substrate from obstructing the sample during sample tilting and also reduces backsplashing during sample thinning.

[0130] Method 2: The sample is mounted in the middle, with both bottom corners or sides bonded to the stage. For example... Figure 2 As shown on the right side (d), two notches are used for mounting the sample. First, the larger outer notch is positioned such that its length is no less than 5 times the sample length and its depth is no less than 1.5 times the sample width. Then, a smaller notch is made in the center of the larger notch, with the same length as the sample and a depth of 15-20 μm. For example, if the sample size is 10 μm... If the notch size is 5µm, then the large notch size should not be less than 50µm. 7.5um (large notch size is generally not less than 40um) 10um), small gap is 10um (15-20)um.

[0131] In practice, the phenomenon of the sample being obscured by the stage substrate due to stage tilting occurs frequently. On the other hand, limited by the internal space of the transmission electron microscope, the tilt angles (α, β) of the stage are only... The angle is 30°, so using a larger opening can effectively reduce sample obstruction caused by stage tilting. Compared to side bonding, this center bonding method is more effective in reducing obstruction; at the same time, samples bonded on both sides are relatively more secure, and samples bonded in the center are less prone to severe bending when thinning. Therefore, the second center bonding method is recommended.

[0132] Sample mounting and long-term storage safety design: To ensure the safety of TEM samples during transfer and long-term storage, in addition to ensuring sufficient sample adhesion, the design also considers "hiding" the sample during adhesion, i.e., protecting the sample through the stage substrate. This "hiding" operation involves two aspects: firstly, horizontal (X / Y direction) sample hiding, meaning that whether side-bonded or center-bonded, the sample does not exceed the surface of the semi-circular stage substrate; secondly, such as... Figure 2 As shown in Figure d, a recessed mounting area is set at the sample mounting position in the height direction (Z direction). This area is formed into a 1-3 μm deep recess by ion beam etching, meaning the sample mounting area will be 1-3 μm lower than the stage substrate. Figure 2 As shown in d. This ensures that the sample is protected by the stage substrate in the X, Y, and Z directions, effectively reducing the risk of the sample falling or being damaged due to contact with foreign objects.

[0133] Sample mounting location marking and fabrication: When multiple TEM slide samples need to be placed on a single stage, each sample (position) needs to be marked to better distinguish between different samples, such as the letters A, B, C, D on commercial stages. Here, we recommend using Roman numerals I, II, III, IV… etc. for marking, as this is relatively simple and easy to fabricate. Figure 2 As shown in d. Of course, letters or numbers can be added for labeling according to one's own habits or preferences. It is worth noting that the relevant markings must be etched through the entire stage depth so that they can be seen in a transmission electron microscope.

[0134] Steps five and six involve TEM sample mounting and thinning, and transmission electron microscopy observation, respectively. All related operations should be performed according to the standard procedures for their respective applications. Figure 3 a and 3b are SEM and TEM images of the TEM sample after mounting and processing, respectively.

[0135] In summary, the present invention has the following significance:

[0136] A simple method for preparing a TEM stage for FIB (Fiber Optic Injection) enables the rapid fabrication of stages made of various materials. This provides more convenient and readily available options for integrated microscopic analysis based on FIB and TEM, especially for samples containing the same elements as those on conventional stages, while also offering the advantage of relatively low cost. Furthermore, the FIB stage provided in this patent is a rudimentary stage, like a blank sheet of paper, leaving ample design space for users to design various mounting positions and methods according to their needs or preferences.

Claims

1. A method for preparing a transmission electron microscope stage for focused ion beam (FIB) applications suitable for various materials, characterized in that, Includes the following steps: Step 1) Prepare the thin slices used to prepare the stage; Step 2) Process the thin sheet to obtain a circular sheet with a diameter of d; Step 3) Cut the circular piece in half to obtain two semicircular pieces, which will serve as a platform; Step 4) Use an ion beam to mark the sample mounting positions and sample labels on the stage; Step 5) Mount the sample on the stage and perform the sample preparation process to complete the preparation of the TEM sample; Step 6) Place the TEM sample into the transmission electron microscope to observe the sample and analyze its microstructure.

2. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, The sheet material includes metals, alloys, and non-brittle non-metallic materials.

3. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, The thickness of the sheet ranges from 20 μm to 50 μm.

4. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, Processing the thin sheet refers to: punching holes in the thin sheet using a punching device to obtain a circular sheet; The drilling equipment includes, but is not limited to, a hole punch and a special sample punch for transmission electron microscopy.

5. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, The method for cutting the circular piece is as follows: use a scalpel with a handle to press and slide along the middle of the circular piece to complete the cutting.

6. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, The steps for marking the sample mounting sites and sample labels on the stage using an ion beam include: Roughing is performed using a large ion beam with current i1, followed by finishing using a small ion beam with current i2; i1 > i2.

7. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, The steps for mounting the sample on the stage are as follows: Step 1) Make a rectangular notch on the surface of the stage, wherein the length and width of the rectangular notch are not less than 3 times the length and width of the sample to be mounted; Step 2) Attach one side of the sample to the stage.

8. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, The steps for mounting the sample on the stage are as follows: Step 1) Create a large rectangular notch around the perimeter of the platform; Step 2) Create a matrix of smaller gaps in the middle of the large rectangular gap; Step 3) Attach the two bottom corners or two sides of the sample to the stage.

9. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that, The length of the rectangular large notch is not less than 5 times the sample length, and the width is not less than 1.5 times the sample width; the length of the matrix small notch is the same as the sample length, and the width ranges from [15 μm to 20 μm].

10. The method for preparing a transmission electron microscope stage for focused ion beam (FIB) applicable to various materials according to claim 1, characterized in that: The sample mounting position and sample label are presented in a hollowed-out form to meet the needs of transmission electron microscopy observation.

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