Universal tooling and preparation method for cold mounting samples with conductive paths

Abstract

The present invention relates to a universal tool for cold-mounting a sample with a conductive path, comprising a sample body, a T-shaped pressure block, a pushing assembly and a lifting assembly, characterized in that the sample body comprises a first and a second U-shaped groove, a threaded hole and a vertical through hole, the piston cooperates with the vertical through hole, the T-shaped pressure block is connected to the sample body to form a cylindrical channel, the pushing assembly comprises a nut and a hand screw, the nuts are respectively fixed on the side surface of the sample body and are coaxial with the cylindrical channel, the lifting assembly comprises a base, a pillar, a driver and a connecting rod, the sample body is connected to the base through the pillar, and the driver drives the piston through the connecting rod. The method for preparing a sample with a conductive path using the above-mentioned tool comprises preparing the tool; placing the sample; pouring the resin; processing the tool; obtaining the sample with a conductive path; and post-processing. The present invention has a simple structure, is easy to manufacture, is convenient to use, and has a wide range of applications. The use of the present invention can effectively ensure that a scanning electron microscope can obtain clear images of the sample.

Description

Technical Field

[0001] The present invention relates to the preparation of samples to be sent to a scanning electron microscope for inspection, and in particular to a universal tool and a preparation method for cold-mounting samples with conductive paths. Background Art

[0002] Scanning electron microscopes (SEMs) combined with energy dispersive spectrometers (EDS) are increasingly being used in scientific research and production to image and analyze the microscopic areas of a sample's surface. Military, aviation, and aerospace industries place high demands on the reliability of electronic components, requiring structural analysis during the component selection and evaluation stages. A crucial step in structural analysis is measuring and analyzing the material composition and thickness of each component using a SEM and EDS. To achieve this, a clear image of the sample area to be analyzed must be obtained using the SEM. The imaging principle of a SEM is to scan the sample surface with a high-energy focused electron beam, sequentially recording the signal intensity of secondary electrons, backscattered electrons, or X-rays at each point. After amplification, the intensity of the corresponding spot on the picture tube is modulated. If electrons accumulated on the sample surface cannot be promptly removed, the resulting SEM image will be directly affected. Therefore, SEM imaging, especially EDS analysis, requires that the sample be conductive. In other words, sample preparation, an essential and critical step in structural analysis, directly impacts the success of SEM inspections.

[0003] The cold mounting method is commonly used for sample preparation, that is, the sample is wrapped in a cold mounting resin with a certain proportion of curing agent, and then the resin sample is placed on an automatic grinder for repeated grinding and polishing until the sample reaches the observation condition. Since the resin is not conductive, the originally conductive semiconductor chips, adhesive materials and pins become non-conductive after the sample is prepared to form an overall sample, making it inconvenient for scanning electron microscopy analysis. To solve this problem, the following method is currently commonly used in the industry: first grind the bottom surface of the sample where the resin is weak until the metal part is exposed, and then spray gold on the surface. The above method has obvious disadvantages. First, the gold spraying layer of the sample will interfere with the analysis of the material composition of the sample surface. Second, the cost of gold spraying is high and the operation is cumbersome. In addition, the scope of application is also limited.

[0004] To address the aforementioned shortcomings of the prior art, the present invention proposes a universal tool and method for cold mounting samples with conductive pathways. The present invention features a simple structure, ease of manufacture, convenience, and wide applicability. This method ensures that all types of samples retain excellent conductivity after cold mounting, thereby ensuring the quality of scanning electron microscopy analysis. Summary of the Invention

[0005] The purpose of the present invention is to provide a universal tool and preparation method for cold-mounting samples with conductive paths, which has a simple structure, is easy to manufacture, is convenient to use, and has a wide range of applicability.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The U-shaped groove and the second U-shaped groove are respectively connected to the vertical through hole and a pair of opposite side surfaces of the sample body, and the threaded holes are respectively located on both sides of the opening of the first U-shaped groove and the second U-shaped groove; the T-shaped pressing block is arranged corresponding to the first U-shaped groove and the second U-shaped groove, and the T-shaped pressing block comprises a horizontal plate and a longitudinal beam, and the horizontal plate is provided with a mounting through hole, and the mounting through hole is aligned with the threaded hole. Correspondingly, the bottom of the longitudinal beam is a concave semi-cylindrical shape, and the T-shaped pressure block is connected to the sample body by bolts, mounting through holes and threaded holes. The longitudinal beam is respectively embedded in the first U-shaped groove and the second U-shaped groove, and the bottom of the longitudinal beam forms a cylindrical channel with the bottom of the first U-shaped groove and the second U-shaped groove respectively; the pushing assembly is arranged corresponding to the first U-shaped groove and the second U-shaped groove, and the pushing assembly includes a nut and a hand screw, and the nuts are respectively fixed on a group of opposite side surfaces of the sample body and are coaxial with the cylindrical channel, and the hand screw cooperates with the nut; the metal rod is placed in the cylindrical channel and can be moved along the cylindrical channel to the vertical through hole under the push of the hand screw; the lifting assembly includes a base, more than three pillars, a driver and a connecting rod, the sample body is detachably connected to the base through the pillars, the driver is installed on the base, and the driver drives the piston to move or stop along the vertical through hole through the connecting rod.

[0008] Furthermore, the sample preparation body is a quadrangular prism cavity structure.

[0009] Furthermore, there are four pillars and they are evenly arranged around the vertical through hole.

[0010] Furthermore, the sum of the length of the metal rod and the radius of the sample corresponds to the sum of the length of the cylindrical channel and the radius of the vertical through hole.

[0011] A method for preparing a sample with a conductive path by cold mounting using one of the above-mentioned universal toolings comprises the following steps:

[0012] S1. Tooling preparation

[0013] S1.1. Place the sample tray on the upper surface of the piston.

[0014] S1.2. Operate the actuator to move the piston upward along the vertical through-hole via the connecting rod;

[0015] S1.3. When the sample tray moves close to the axis of the cylindrical channel, the actuator stops the sample tray;

[0016] S1.4. Apply mold release agent to the vertical through-holes, sample tray, and inner surface of the longitudinal beams.

[0017] S1.5. Turn the thumb screw counterclockwise until it releases from the nut. Insert the metal rod through the nut into the cylindrical passage.

[0018] S1.6. Tighten the thumb screw into the nut and rotate clockwise, pushing the metal rod toward the vertical through-hole. Observe from above the vertical through-hole until the front end of the metal rod enters the vertical through-hole.

[0019] S2. Place the sample

[0020] S2.1. Use tweezers to place the sample on the sample tray and hold it down, keeping the side of the sample to be observed facing downward and in contact with the sample tray.

[0021] S2.2. Operate the actuator to move the piston upward via the connecting rod to one-third of the sample height.

[0022] S2.3. Turn the thumb screw clockwise to push the metal rod along the cylindrical channel toward the sample until the tip of the metal rod contacts the sample.

[0023] S2.4. Operate the actuator to fine-tune the piston height using the connecting rod until the center axis of the metal rod is located in the middle of the sample in the vertical direction.

[0024] S2.5. Use both hands to turn the thumb screw clockwise 5 0 -10 0 , so that the metal rods on both sides move toward each other and clamp the sample;

[0025] S3. Pouring resin

[0026] S3.1. Pour the curing agent and cold mounting resin into a container and mix them at a weight percentage of 12%-25%;

[0027] S3.2. Stir the mixture clockwise or counterclockwise until uniform.

[0028] S3.3. Pour the mixture into the vertical through-hole until the mixture fills the vertical through-hole.

[0029] S4. Processing tooling

[0030] S4.1. Place the tooling after step S3.3 into a cold mounting vacuum apparatus and maintain pressure at 0.2-0.4 bar for 30 minutes.

[0031] S4.2. After completing step S4.1, let it stand for 12 hours until the mixture solidifies;

[0032] S5. Obtaining samples with conductive paths

[0033] S5.1. Remove the tooling;

[0034] S5.2. Remove the bolts from the mounting holes and threaded holes, and remove the T-shaped clamps from the first and second U-shaped grooves, respectively;

[0035] S5.3. Operate the actuator to move the piston upward via the connecting rod until the resin-encapsulated sample with the conductive path is pushed out of the vertical through-hole.

[0036] S6. Post-processing of samples with conductive paths

[0037] S6.1. Place the resin-encapsulated sample with conductive paths on an automatic grinder and repeatedly grind and polish until the sample meets observation conditions.

[0038] The working process of the present invention is as follows: a resin-encapsulated sample with a conductive path that meets the conditions for scanning electron microscope observation is produced according to the above technical solution; the sample is fixed on a special base for scanning electron microscope inspection, and the end of the metal rod exposed on the sample is connected to the special base with a metal wire; the special base is placed in the scanning electron microscope sample chamber and fixed on the base; the scanning electron microscope is operated to inspect the sample, and the electrons accumulated on the sample surface are guided out through the metal rod, wire and base to ensure clear imaging of the sample micro area and cooperate with the energy spectrometer for component analysis.

[0039] The present invention uses a piston to move the sample tray up and down and fine-tune it to a desired height, and uses a pushing assembly to push metal rods from both sides of the sample tray toward each other and clamp the sample, so that good electrical contact between the two is maintained through resin packaging.

[0040] The present invention can effectively ensure that the scanning electron microscope can clearly image the area to be analyzed of the sample, and cooperate with the energy spectrometer to measure and analyze the material composition and thickness of each part of the component, providing accurate and reliable data for component selection and evaluation.

[0041] The invention has the advantages of simple structure, easy manufacture, convenient use and wide application range. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a structural schematic diagram of the present invention;

[0043] Figure 2 is a cross-sectional view of the present invention;

[0044] Figure 3 This is a schematic diagram of the sample preparation structure of the present invention;

[0045] Figure 4 This is a schematic diagram of the T-shaped pressing block structure of the present invention;

[0046] Figure 5 for Figure 1 A top view of

[0047] Figure 6 It is a top view of the working state of the present invention.

[0048] In the figure, 1-sample body; 1.1-first U-shaped groove; 1.2-second U-shaped groove; 1.3-threaded hole; 1.4-vertical through hole; 2-T-shaped pressure block; 2.1-cross plate; 2.1.1-mounting through hole; 2.2-longitudinal beam; 3-pushing assembly; 3.1-nut; 3.2-thumb screw; 4-lifting assembly; 4.1-base; 4.2-pillar; 4.3-drive; 4.4-connecting rod; 5-piston; 6-sample tray; 7-bolt; 8-cylindrical channel; 9-metal rod. DETAILED DESCRIPTION

[0049] The present invention will be further described below with reference to the accompanying drawings and examples, but these examples should not be construed as limiting the present invention.

[0050] As shown in the figure, a universal tool for cold mounting to prepare samples with conductive paths includes a sample body 1, a T-shaped pressure block 2, a pushing component 3 and a lifting component 4. The sample body 1 is a columnar cavity structure. The sample body 1 includes a first U-shaped groove 1.1, a second U-shaped groove 1.2, a threaded hole 1.3 and a vertical through hole 1.4. The vertical through hole 1.4 passes through the sample body 1 from top to bottom. The piston 5 cooperates with the vertical through hole 1.4. The sample tray 6 is placed on the upper surface of the piston 5. The first U-shaped groove 1.1 and the second U-shaped groove 1.2 are symmetrically arranged. The first U-shaped groove 1.1 and The second U-shaped groove 1.2 opens on the upper surface of the sample body 1, the first U-shaped groove 1.1 and the second U-shaped groove 1.2 are respectively connected to the vertical through hole 1.4 and a group of opposite side surfaces of the sample body 1, and the threaded holes 1.3 are respectively located on both sides of the openings of the first U-shaped groove 1.1 and the second U-shaped groove 1.2; the T-shaped pressing block 2 is arranged corresponding to the first U-shaped groove 1.1 and the second U-shaped groove 1.2, the T-shaped pressing block 2 includes a horizontal plate 2.1 and a longitudinal beam 2.2, the horizontal plate 2.1 is provided with a mounting through hole 2.1.1, the mounting through hole 2.1.1 corresponds to the threaded hole 1.3 one by one, and the longitudinal beam The bottom of 2.2 is a concave semi-cylindrical shape. The T-shaped pressure block 2 is connected to the sample body 1 by the cooperation of the bolt 7, the mounting through hole 2.1.1 and the threaded hole 1.3. The longitudinal beam 2.2 is respectively embedded in the first U-shaped groove 1.1 and the second U-shaped groove 1.2. The bottom of the longitudinal beam 2.2 forms a cylindrical channel 8 with the bottom of the first U-shaped groove 1.1 and the second U-shaped groove 1.2; the pushing component 3 is corresponding to the first U-shaped groove 1.1 and the second U-shaped groove 1.2. The pushing component 3 includes a nut 3.1 and a hand screw 3.2. The nut 3.1 is fixed to a group of corresponding On the side surface thereof and coaxial with the cylindrical channel 8, the hand screw 3.2 cooperates with the nut 3.1; the metal rod 9 is placed in the cylindrical channel 8 and can be moved along the cylindrical channel 8 toward the vertical through hole 1.4 under the push of the hand screw 3.2; the lifting assembly 4 includes a base 4.1, more than three pillars 4.2, a driver 4.3 and a connecting rod 4.4, the sample body 1 is detachably connected to the base 4.1 through the pillars 4.2, the driver 4.3 is installed on the base 4.1, and the driver 4.3 drives the piston 5 to move or stop along the vertical through hole 1.4 through the connecting rod 4.4.

[0051] A preferred embodiment is: in the above solution, the sample body 1 is a quadrangular prism cavity structure.

[0052] A preferred embodiment is: in the above solution, there are four pillars 4.2 and they are evenly arranged around the vertical through hole 1.4.

[0053] A preferred embodiment is: in the above solution, the sum of the length of the metal rod 9 and the radius of the sample corresponds to the sum of the length of the cylindrical channel 8 and the radius of the vertical through hole 1.4.

[0054] A method for preparing a sample with a conductive path by cold mounting using one of the above-mentioned universal toolings comprises the following steps:

[0055] S1. Tooling preparation

[0056] S1.1. Place the sample tray 6 on the upper surface of the piston 5;

[0057] S1.2. The operating actuator 4.3 drives the piston 5 to move upward along the vertical through hole 1.4 through the connecting rod 4.4;

[0058] S1.3. When the sample tray 6 moves close to the axis of the cylindrical channel 8, the actuator 4.3 stops the sample tray 6;

[0059] S1.4. The vertical through-hole 1.4, the sample tray 6 and the inner surface of the longitudinal beam 2.2 are coated with a release agent;

[0060] S1.5. Rotate the thumb screw 3.2 counterclockwise until the thumb screw 3.2 is disengaged from the nut 3.1. Insert the metal rod 9 through the nut 3.1 into the cylindrical channel 8.

[0061] S1.6. Screw thumb screw 3.2 into nut 3.1 and rotate clockwise to push metal rod 9 toward vertical through-hole 1.4. Observe from above vertical through-hole 1.4 until the front end of metal rod 9 enters vertical through-hole 1.4.

[0062] S2. Place the sample

[0063] S2.1. Place the sample on the sample tray 6 with tweezers and press it, keeping the side of the sample to be observed facing down in contact with the sample tray 6;

[0064] S2.2. Operate the actuator 4.3 to move the piston 5 upwards to 1 / 3 of the sample height through the connecting rod 4.4;

[0065] S2.3. Turn thumb screw 3.2 clockwise to push metal rod 9 along cylindrical channel 8 toward the sample until the front end of metal rod 9 contacts the sample.

[0066] S2.4. Operate the actuator 4.3 to fine-tune the level of the piston 5 through the connecting rod 4.4 until the central axis of the metal rod 9 is located in the middle of the sample in the vertical direction;

[0067] S2.5. Use both hands to turn the thumb screw 3.2 clockwise to rotate it 5 0 -10 0 , push the metal rods 9 on both sides to move toward each other and clamp the sample;

[0068] S3. Pouring resin

[0069] S3.1. Pour the curing agent and cold mounting resin into a container and mix them at a weight percentage of 12%-25%;

[0070] S3.2. Stir the mixture clockwise or counterclockwise until uniform.

[0071] S3.3. Pour the mixed liquid into the vertical through hole 1.4 until the mixed liquid fills the vertical through hole 1.4;

[0072] S4. Processing tooling

[0073] S4.1. Place the tooling after step S3.3 into a cold mounting vacuum apparatus and maintain pressure at 0.2-0.4 bar for 30 minutes.

[0074] S4.2. After completing step S4.1, let it stand for 12 hours until the mixture solidifies;

[0075] S5. Obtaining samples with conductive paths

[0076] S5.1. Remove the tooling;

[0077] S5.2. The bolt 7 is withdrawn from the mounting through hole 2.1.1 and the threaded hole 1.3, and the T-shaped pressure block 2 is removed from the first U-shaped groove 1.1 and the second U-shaped groove 1.2;

[0078] S5.3. The actuator 4.3 drives the piston 5 to move upward through the connecting rod 4.4 until the resin-encapsulated sample with a conductive path is pushed out of the vertical through-hole 1.4;

[0079] S6. Post-processing of samples with conductive paths

[0080] S6.1. Place the resin-encapsulated sample with conductive paths on an automatic grinder and repeatedly grind and polish until the sample meets observation conditions.

[0081] The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

Claims

1. A universal tool for cold mounting a sample with a conductive path, comprising a sample preparation body (1), a T-shaped pressing block (2), a pushing assembly (3) and a lifting assembly (4), characterized in that: The sample preparation body (1) is a columnar cavity structure. The sample preparation body (1) includes a first U-shaped groove (1.1), a second U-shaped groove (1.2), a threaded hole (1.3) and a vertical through hole (1.4). The vertical through hole (1.4) passes through the sample preparation body (1) from top to bottom. The piston (5) cooperates with the vertical through hole (1.4). The sample tray (6) is placed on the upper surface of the piston (5). The first U-shaped groove (1.1) and the second U-shaped groove (1.2) are symmetrically arranged. The first U-shaped groove (1.1) and the second U-shaped groove (1.2) are opened on the upper surface of the sample preparation body (1). The first U-shaped groove (1.1) and the second U-shaped groove (1.2) are respectively connected to each other. A vertical through hole (1.4) and a set of opposite side surfaces of the sample body (1) are provided, and the threaded holes (1.3) are respectively located on both sides of the openings of the first U-shaped groove (1.1) and the second U-shaped groove (1.2); the T-shaped pressing block (2) is arranged corresponding to the first U-shaped groove (1.1) and the second U-shaped groove (1.2); the T-shaped pressing block (2) includes a horizontal plate (2.1) and a longitudinal beam (2.2); the horizontal plate (2.1) is provided with mounting through holes (2.1.1), and the mounting through holes (2.1.1) correspond to the threaded holes (1.3) one by one; the bottom of the longitudinal beam (2.2) is in the shape of a concave semi-cylinder; the T-shaped pressing block (2) is connected to the first U-shaped groove (1.1) and the second U-shaped groove (1.2) by bolts (7), mounting through holes ( The longitudinal beam (2.2) is respectively embedded in the first U-shaped groove (1.1) and the second U-shaped groove (1.2), and the bottom of the longitudinal beam (2.2) forms a cylindrical channel (8) with the bottom of the first U-shaped groove (1.1) and the bottom of the second U-shaped groove (1.2); the pushing component (3) is arranged corresponding to the first U-shaped groove (1.1) and the second U-shaped groove (1.2), and the pushing component (3) includes a nut (3.1) and a hand screw (3.2), and the nut (3.1) is respectively fixed on a group of opposite side surfaces of the sample body (1) and is coaxial with the cylindrical channel (8). , a hand screw (3.2) cooperates with a nut (3.1); a metal rod (9) is placed in a cylindrical channel (8) and can be moved toward a vertical through hole (1.4) along the cylindrical channel (8) under the push of the hand screw (3.2); a lifting assembly (4) comprises a base (4.1), three or more pillars (4.2), a driver (4.3) and a connecting rod (4.4); the sample body (1) is detachably connected to the base (4.1) through the pillars (4.2); the driver (4.3) is installed on the base (4.1); and the driver (4.3) drives the piston (5) to move or stop along the vertical through hole (1.4) through the connecting rod (4.4).

2. The universal tool for cold mounting samples with conductive paths according to claim 1, characterized in that: The sample preparation body (1) is a quadrangular prism-shaped cavity structure.

3. The universal tool for cold mounting a sample with a conductive path according to claim 1 or 2, characterized in that: There are four pillars (4.2) and they are evenly arranged around the vertical through hole (1.4).

4. The universal tool for cold mounting a sample with a conductive path according to claim 1 or 2, characterized in that: The sum of the length of the metal rod (9) and the radius of the sample corresponds to the sum of the length of the cylindrical channel (8) and the radius of the vertical through hole (1.4).

5. The universal tool for cold mounting a sample with a conductive path according to claim 3, characterized in that: The sum of the length of the metal rod (9) and the radius of the sample corresponds to the sum of the length of the cylindrical channel (8) and the radius of the vertical through hole (1.4).

6. A method for cold mounting a sample with a conductive path using the universal tooling according to any one of claims 1 to 5, comprising the following steps: S1. Tooling preparation S1.

1. Place the sample tray (6) on the upper surface of the piston (5); S1.

2. The operating actuator (4.3) drives the piston (5) to move upward along the vertical through hole (1.4) through the connecting rod (4.4); S1.

3. When the sample tray (6) moves close to the axis of the cylindrical channel (8), the actuator (4.3) is operated to stop the sample tray (6); S1.

4. Apply a release agent to the inner surfaces of the vertical through-hole (1.4), the sample tray (6), and the longitudinal beam (2.2); S1.

5. Rotate the thumb screw (3.2) counterclockwise until the thumb screw (3.2) is disengaged from the nut (3.1). Insert the metal rod (9) through the nut (3.1) into the cylindrical channel (8). S1.

6. Screw the thumb screw (3.2) into the nut (3.1) and rotate it clockwise to push the metal rod (9) toward the vertical through-hole (1.4). Observe from above the vertical through-hole (1.4) until the front end of the metal rod (9) enters the vertical through-hole (1.4). S2. Place the sample S2.

1. Place the sample on the sample tray (6) with tweezers and press it down, keeping the side of the sample to be observed facing downward in contact with the sample tray (6); S2.

2. Operate the actuator (4.3) to move the piston (5) upward to 1 / 3 of the sample height through the connecting rod (4.4); S2.

3. Turn the thumb screw (3.2) clockwise to push the metal rod (9) along the cylindrical channel (8) toward the sample until the front end of the metal rod (9) contacts the sample. S2.

4. Operate the actuator (4.3) to fine-tune the level of the piston (5) through the connecting rod (4.4) until the center axis of the metal rod (9) is located in the middle of the sample in the vertical direction; S2.

5. Turn the thumb screw (3.2) clockwise with both hands simultaneously. 0 -10 0 , so that the metal rods (9) on both sides move toward each other and clamp the sample; S3. Pouring resin S3.

1. Pour the curing agent and cold mounting resin into a container and mix them at a weight percentage of 12%-25%; S3.

2. Stir the mixture clockwise or counterclockwise until evenly combined. S3.

3. Pour the mixed solution into the vertical through hole (1.4) until the mixed solution fills the vertical through hole (1.4); S4. Processing tooling S4.

1. Place the tooling after step S3.3 into a cold mounting vacuum apparatus and maintain pressure at 0.2-0.4 bar for 30 minutes. S4.

2. After completing step S4.1, let it stand for 12 hours until the mixture solidifies; S5. Obtaining samples with conductive paths S5.

1. Remove the tooling; S5.

2. Remove the bolt (7) from the mounting through hole (2.1.1) and the threaded hole (1.3), and remove the T-shaped pressure block (2) from the first U-shaped groove (1.1) and the second U-shaped groove (1.2); S5.

3. The actuator (4.3) drives the piston (5) to move upward through the connecting rod (4.4) until the resin-encapsulated sample with a conductive path is pushed out of the vertical through-hole (1.4); S6. Post-processing of samples with conductive paths S6.

1. Place the resin-encapsulated sample with conductive paths on an automatic grinder and repeatedly grind and polish until the sample meets observation conditions.

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