Scanning electron microscope sample preparation method and system

Abstract

The invention discloses a scanning electron microscope sample preparation method and a scanning electron microscope sample preparation system, which are used for reducing the loss and pollution of a sample of a trace material in a preparation process to the greatest extent and improving the treatment efficiency and the imaging quality at the same time. The method comprises the steps that a sample is extracted from an electronic component, the sample is fixed through an optical fixing method, and the optical fixing method is used for fixing the sample in a non-contact mode; the fixed sample is placed in a first mixed solution, low-frequency ultrasonic cleaning is carried out for a preset duration, pollutants on the surface of the sample are removed, and the cleaned sample is obtained; dehydrating the cleaned sample by using a second mixed solution, and blow-drying the sample by using inert gas so as to enable the scanning electron microscope to perform detection; wherein the inert gas is used for slowing down the oxidation of the sample, and the second mixed solution comprises a mixed solution of ethanol and acetone.

Description

Technical Field

[0001] The present invention relates to the technical field of component detection, and in particular to a scanning electron microscope sample preparation method and system. Background Art

[0002] Scanning Electron Microscope (SEM), also known as SEM for short, uses high voltage to strike the target to produce X-ray penetration to detect electronic components, the internal structure quality of semiconductor packaging products, and the welding quality of various types of solder joints in surface mount technology (SMT). The SEM sample preparation method refers to a series of steps to process and prepare the sample to meet the observation and analysis requirements of the SEM.

[0003] Since SEM analysis has high requirements for the surface state of the sample, the integrity, cleanliness and good conductivity of the sample must be ensured during the SEM sample preparation process. However, traditional SEM sample preparation methods have many challenges for trace materials (such as nano-scale powdered materials on servers), which can easily cause sample loss, contamination or deformation, which directly affects the accuracy and reliability of the final analysis results. Summary of the invention

[0004] The present invention provides a scanning electron microscope sample preparation method and system, which are used to minimize the loss and contamination of trace material samples during the preparation process, while improving processing efficiency and imaging quality.

[0005] In a first aspect, an embodiment of the present invention provides a method for preparing a sample under a scanning electron microscope, the method comprising:

[0006] Extracting a sample from an electronic component and fixing the sample using an optical fixing method, wherein the optical fixing method is used to fix the sample in a non-contact manner;

[0007] The fixed sample is placed in the first mixed solution, and low-frequency ultrasonic cleaning is performed for a preset time to remove pollutants on the surface of the sample to obtain a cleaned sample;

[0008] The cleaned sample is dehydrated using a second mixed solution and blown dry using an inert gas so as to be detected by a scanning electron microscope; wherein the inert gas is used to slow down oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

[0009] The optical fixing method of this embodiment can highly retain the original state of trace materials, avoid the risks brought by traditional physical contact fixing, and can minimize the loss and contamination of samples of trace materials during the preparation process, while improving processing efficiency and imaging quality. In this embodiment, a low-frequency ultrasonic cleaning method is adopted, which can improve the cleanliness of the sample while ensuring the integrity of the sample, and is more suitable for cleaning trace materials in electronic components. In this embodiment, an inert gas can be used to dry the sample, which can effectively slow down the oxidation problem of the sample during the drying process. In this embodiment, a mixed solution of ethanol and acetone is used to dehydrate the sample. Due to the good volatility of ethanol and acetone, the residue of the mixed solution of ethanol and acetone on the sample can be minimized to ensure the authenticity of the sample analysis results.

[0010] As an optional implementation, the optical fixing method includes light-curing resin or photon sintering technology.

[0011] The optical fixation method in this embodiment can highly preserve the original state of trace materials, avoid the risks brought by traditional physical contact fixation, and minimize the loss of samples during the preparation process.

[0012] As an optional implementation, the inert gas includes nitrogen or argon.

[0013] In this embodiment, nitrogen or argon is used to dry the sample, which can effectively reduce the oxidation problem of the sample during the drying process.

[0014] As an optional implementation, the method further includes:

[0015] Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

[0016] This embodiment adopts a method of performing spraying in a vacuum environment, and controls the uniformity of the spraying by the vacuum degree to ensure that the sprayed metal film is uniform and continuous on the sample surface, thereby ensuring the effectiveness of the sample's conductivity and facilitating SEM detection.

[0017] As an optional implementation, the method further includes:

[0018] The dried samples were cut using a cutting machine equipped with a diamond blade;

[0019] The cut samples are polished using micro-particle abrasive paste until the cut section reaches the preset effect.

[0020] In this embodiment, a diamond blade cutting machine is used to cut the dry sample, which can improve the cutting accuracy of the sample and avoid the internal structure change caused by thermal damage and mechanical stress of the sample. At the same time, the cut sample is polished using a micro-particle abrasive paste, which can reduce the cost while ensuring the polishing effect.

[0021] In a second aspect, an embodiment of the present invention provides a scanning electron microscope sample preparation system, the system comprising:

[0022] A sample fixing device, used for extracting a sample from an electronic component, and fixing the sample using an optical fixing method, wherein the optical fixing method is used for fixing the sample in a non-contact manner;

[0023] A sample cleaning device, used to place the fixed sample in the first mixed solution, use low-frequency ultrasonic cleaning for a preset time to remove pollutants on the sample surface, and obtain a cleaned sample;

[0024] The sample drying device is used to dehydrate the cleaned sample using a second mixed solution and blow dry it using an inert gas so that the scanning electron microscope can detect it; wherein the inert gas is used to slow down the oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

[0025] As an optional implementation, the optical fixing method includes light-curing resin or photon sintering technology.

[0026] As an optional implementation, the inert gas includes nitrogen or argon.

[0027] As an optional embodiment, the system further includes a spraying device, which is specifically used for:

[0028] Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

[0029] As an optional embodiment, the system further comprises a cutting device, specifically used for:

[0030] The dried samples were cut using a cutting machine equipped with a diamond blade;

[0031] The cut sample is polished using a microparticle grinding paste until the cut cross section reaches a preset effect. In a third aspect, an embodiment of the present invention further provides a scanning electron microscope sample preparation device, the device comprising:

[0032] A sample fixing module, used for extracting samples from electronic components and fixing the samples using an optical fixing method, wherein the optical fixing method is used for non-contact fixing of the samples;

[0033] A sample cleaning module is used to place the fixed sample in the first mixed solution, use low-frequency ultrasonic cleaning for a preset time to remove pollutants on the sample surface, and obtain a cleaned sample;

[0034] The sample drying module is used to dehydrate the cleaned sample using a second mixed solution and blow dry it using an inert gas so that the scanning electron microscope can detect it; wherein the inert gas is used to slow down the oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

[0035] As an optional implementation, the optical fixing method includes light-curing resin or photon sintering technology.

[0036] As an optional implementation, the inert gas includes nitrogen or argon.

[0037] As an optional implementation, the device further includes a conductive module, specifically used for:

[0038] Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

[0039] As an optional embodiment, the device further includes a cutting and polishing module, which is specifically used for:

[0040] The dried samples were cut using a cutting machine equipped with a diamond blade;

[0041] The cut samples are polished using micro-particle abrasive paste until the cut section reaches the preset effect.

[0042] In a third aspect, an embodiment of the present invention further provides a computer storage medium on which a computer program is stored, and when the program is executed by a processor, it is used to implement the steps of any one of the methods described in the first aspect above.

[0043] In a fourth aspect, the present application provides a computer program product, comprising: a computer program code, when the computer program code is executed on a computer, the computer executes any one of the methods described in the first aspect.

[0044] These and other aspects of the present application will be more clearly understood in the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0046] Figure 1 A flowchart of a scanning electron microscope sample preparation method provided by an embodiment of the present invention;

[0047] Figure 2 A specific implementation flow chart of SEM sample preparation provided by an embodiment of the present invention;

[0048] Figure 3A-3B A sample schematic diagram provided for an embodiment of the present invention;

[0049] Figure 4 A schematic diagram of a scanning electron microscope sample preparation system provided by an embodiment of the present invention;

[0050] Figure 5 A schematic diagram of a scanning electron microscope sample preparation device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] In the embodiments of the present invention, the term "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0053] The application scenarios described in the embodiments of the present invention are intended to more clearly illustrate the technical solutions of the embodiments of the present invention, and do not constitute a limitation on the technical solutions provided by the embodiments of the present invention. It is known to those skilled in the art that with the emergence of new application scenarios, the technical solutions provided by the embodiments of the present invention are also applicable to similar technical problems. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0054] Before introducing a scanning electron microscope sample preparation method provided in an embodiment of the present application, in order to facilitate understanding, the technical background of the embodiment of the present application is first introduced in detail below.

[0055] Scanning Electron Microscope (SEM), also known as SEM for short, uses high voltage to impact the target material to generate X-ray penetration to detect electronic components, the internal structure quality of semiconductor packaging products, and the welding quality of various types of solder joints in surface mount technology (SMT). The SEM sample preparation method refers to a series of steps to process and prepare the sample to meet the observation and analysis requirements of the scanning electron microscope. The core requirements of SEM sample preparation include: (1) The sample does not contain moisture: wet samples will release water vapor, affecting the vacuum degree and imaging quality. (2) The sample does not contain volatiles and pollutants: volatiles and pollutants will contaminate components and affect the detection effect. (3) The sample is conductive: non-conductive samples will cause electron beam accumulation, affecting image quality, and usually require gold or carbon plating to improve conductivity.

[0056] Since SEM analysis has high requirements for the surface state of the sample, the integrity, cleanliness and good conductivity of the sample must be ensured during the SEM sample preparation process. However, traditional SEM sample preparation methods have many challenges for trace materials (such as nano-level and micron-level powder materials on servers), which can easily cause sample loss, contamination or deformation, which directly affects the accuracy and reliability of the final analysis results.

[0057] The following problems may occur during sample preparation:

[0058] 1) Sample damage problem;

[0059] 1a) Mechanical damage: In traditional SEM sample preparation, physical treatments such as cutting, grinding and polishing are usually required. These processes can easily cause mechanical damage to trace materials, especially when dealing with brittle or soft samples.

[0060] 1b) Chemical damage: Chemical reagents used in the cleaning and corrosion processes may damage certain sensitive materials, resulting in changes in the chemical properties of the sample or structural damage.

[0061] 2) Sample contamination problem;

[0062] 2a) Surface contamination: During the sample preparation process, it is easy to introduce contaminants such as dust and grease, especially when operating in an open environment.

[0063] 2b) Cross-contamination: When the same equipment and tools are used to process different samples, cross-contamination may occur, which will affect the accuracy of the analytical results.

[0064] 3) Sample information loss problem;

[0065] 3a) Loss of morphological information: Improper sample preparation, such as excessive polishing or cleaning, may result in loss of microscopic morphological information on the sample surface.

[0066] 3b) Loss of composition information: During the coating or cleaning process, some elements in the sample may be dissolved or masked, making it impossible to accurately analyze the composition of the sample.

[0067] The problems existing in the prior art mainly include damage, contamination, information loss, insufficient conductivity and insufficient technical inspiration during the sample preparation process. These problems exist mainly because the traditional SEM sample preparation method does not fully consider the particularity of trace materials when designing. In order to solve the above technical problems, this embodiment provides a scanning electron microscope sample preparation method for trace materials, which can minimize the loss and contamination of samples of trace materials during the preparation process, while improving processing efficiency and imaging quality.

[0068] It should be noted that the samples in this embodiment are trace materials, such as nano-level, micron-level powdered materials, porous materials, etc., such as tiny solids and porous materials in servers. The samples in this embodiment belong to the field of electronic equipment and electronic components, and are used for sample detection of electronic equipment and electronic components in the electronics field to analyze the operation and failure of electronic equipment and electronic components.

[0069] like Figure 1 As shown, the implementation process of the scanning electron microscope sample preparation method provided in this embodiment is as follows:

[0070] Step 100: extracting a sample from an electronic component, and fixing the sample using an optical fixing method, wherein the optical fixing method is used to fix the sample in a non-contact manner;

[0071] In practice, a precise micro-sampling tool is used to extract the desired sample from the electronic components, and the sampling amount is usually in the range of micrograms to milligrams. Among them, the micro-sampling tool includes but is not limited to: a micropipette, a micro-scraper, ion beam cutting, etc. This embodiment does not impose too many restrictions on this. The sample extracted from the electronic components using the micro-sampling tool is usually very small, with an order of magnitude in the range of micrograms to milligrams, and is suitable for sample extraction of trace materials.

[0072] The extracted sample is placed on a metal or carbon sample table with micron-level flatness, and a non-contact optical fixation method is used to ensure that the sample is stable and does not move during subsequent processing. The extracted sample is placed on a metal or carbon sample table with micron-level flatness. Such flatness ensures that the details of the sample surface can be clearly displayed when observed under an electron microscope.

[0073] In some embodiments, the optical fixing method includes light-curable resin or photonic sintering technology.

[0074] Among them, photocurable resin is a technology that cures resin through light. When the resin is exposed to light of a specific wavelength, it will quickly cure and form a hard shell to fix the sample. Photocuring has a fast speed and high production efficiency; high energy utilization rate and energy saving; relatively few volatile organic compounds (Volatile Organic Compounds, VOC) and environmentally friendly; it can be coated on a variety of substrates, such as paper, plastic, leather, etc. Photocurable resin is simple to operate and relatively low in cost; fast curing speed and high production efficiency; environmentally friendly, with almost no pollutant emissions.

[0075] Photon sintering technology is a method of sintering materials using lasers or other high-energy photon sources. By precisely controlling the energy and irradiation time of the photons, local sintering can be achieved without contacting the sample, thereby fixing the sample. Photon sintering technology uses low-temperature operation and is suitable for the processing of heat-sensitive materials. It uses a non-contact fixation method to avoid physical damage to the sample, and has high fixation accuracy, which can achieve the manufacture of fine structures. Photon sintering technology has high accuracy and is suitable for the manufacture of complex and fine structures. In addition, non-contact processing reduces physical damage to the material and can be performed at a lower temperature, which is suitable for sample fixation of a variety of materials.

[0076] In practice, in order to ensure that the sample is stable and does not move during subsequent processing, this embodiment uses a non-contact optical fixation method, which can avoid problems such as sample loss and information loss during the fixation process compared to a contact sample fixation method.

[0077] Step 101, placing the fixed sample in a first mixed solution, using low-frequency ultrasonic cleaning for a preset time to remove pollutants on the sample surface, and obtaining a cleaned sample;

[0078] In some embodiments, the fixed sample is cleaned by the following method:

[0079] The fixed sample is placed in the first mixed solution and cleaned with low-frequency ultrasonic waves for a preset time to obtain a cleaned sample.

[0080] Optionally, the first mixed solution includes a mixed solution of deionized water and a non-ionic surfactant.

[0081] Among them, low-frequency ultrasonic cleaning is suitable for cleaning precision parts, tiny gaps and holes, such as electronic components, medical devices and other samples. Its frequency is between 10Mhz and 20Mhz. Low-frequency ultrasonic waves have a longer wavelength and are suitable for cleaning stains.

[0082] During the implementation, the fixed sample is placed in a mixed solution of deionized water and a mild non-ionic surfactant, and low-frequency ultrasonic cleaning is used for 5-10 minutes to remove dust and oil on the surface of the sample. The duration of low-frequency ultrasonic cleaning can be determined according to the diffusion degree of the sample. If the diffusion time is too short, the diffusion degree of the sample may be insufficient, and if the diffusion time is too long, the diffusion degree may be too large, destroying the information contained in the sample.

[0083] Step 102: Dehydrate the cleaned sample using a second mixed solution and blow dry it using an inert gas so as to enable detection by a scanning electron microscope; wherein the inert gas is used to slow down oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

[0084] In some embodiments, the cleaned sample is dried by:

[0085] The cleaned sample is dehydrated using the second mixed solution and blown dry using an inert gas, wherein the inert gas is used to slow down oxidation of the sample.

[0086] Optionally, the second mixed solution includes a mixed solution of ethanol and acetone.

[0087] During implementation, this embodiment uses a mixed solution of ethanol and acetone to dehydrate the sample. Since the mixed solution of ethanol and acetone is an organic chemical, the organic solvent on the surface of the sample is easier to clean and will not affect the sample. In addition, since ethanol and acetone have good volatility and can evaporate quickly, the sample is not easily oxidized, and SEM is not easy to detect ethanol and acetone.

[0088] Optionally, the ratio of ethanol to acetone in the mixed solution of ethanol and acetone in this embodiment is 2:1. The second mixed liquid can effectively dissolve organic residues on the sample that are difficult to remove, and can effectively observe the surface of the sample. Since the second mixed liquid evaporates quickly, it can evaporate quickly when purging with inert gas, thereby reducing the oxidation process and taking away the water vapor residue of the sample (the water vapor residue will affect the normal test of the electron microscope).

[0089] Optionally, the inert gas includes nitrogen or argon.

[0090] During implementation, after the cleaned sample is dehydrated with the second mixed solution, it is blown dry with pure inert gas immediately after slight shaking. Among them, a drying device can be used to blow dry the dehydrated sample with inert gas. The slight shaking is performed by artificial shaking. Since the ultrasonic shaking has been completed, the diffusion of the sample is better, and the degree of slight shaking can be controlled by observing whether there is obvious agglomeration, that is, when no obvious agglomeration is observed. The inert gas can be nitrogen or argon, but the cost of argon is higher and it is not as cost-effective as nitrogen. There are also methods for drying samples by drying, but the method of drying samples easily leads to oxidation of the samples. In this embodiment, the method of blowing the samples with inert gas can quickly dry the samples, reduce the contact time between the samples and the air, and reduce the oxidation process of the samples.

[0091] In some embodiments, the present embodiment also provides a method for conducting a sample, which is specifically as follows:

[0092] Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

[0093] In implementation, for samples that have been oxidized or have poor conductivity, conductive treatment is required. Since trace materials may not be able to directly export charges, it is necessary to evaporate a metal film with a thickness of 5 to 10 nanometers on the surface of the sample to enhance conductivity. Optionally, this embodiment can use an ion sputtering coating machine to perform metal spraying in a vacuum environment to ensure that the sprayed metal film uniformly and continuously covers the entire sample surface. In implementation, different vacuum degrees in a vacuum environment will affect the uniformity of the sprayed metal film on the sample surface. The ion sputtering coating machine itself has a vacuum pumping device to achieve a vacuum environment, and this embodiment can use an optical fixing method to allow the sample to be better adsorbed on the sample table to avoid further oxidation of the sample. Optionally, observe the vacuum degree when using the ion sputtering coating machine to evacuate the vacuum. When the vacuum degree reaches 0.05Mpa, perform degassing treatment and then perform vacuum treatment. The maximum vacuum degree of the secondary vacuum pumping cannot exceed 0.05Mp. The longer the waiting time, the better the coating effect; the coating time should not exceed 15 seconds, otherwise the coating layer will be too thick to affect the actual imaging effect of the sample surface.

[0094] In some embodiments, the present embodiment also provides a method for accurately cutting and polishing a sample, as shown below:

[0095] The dried samples were cut using a cutting machine equipped with a diamond blade;

[0096] The cut samples are polished using micro-particle abrasive paste until the cut section reaches the preset effect.

[0097] During implementation, for samples whose cross sections need to be observed, the samples can be cut and then polished, wherein a precision cutting machine equipped with a diamond blade is used to slowly cut the samples to avoid thermal damage and changes in the internal structure caused by mechanical stress. The cut samples are polished on a special polishing cloth with a micro-particle abrasive paste until the cut cross section reaches a mirror effect without obvious scratches. Compared with the method of polishing with an argon ion beam polisher, this embodiment uses a micro-particle abrasive paste for polishing, which can reduce costs while ensuring the polishing effect.

[0098] Among them, the specific polishing is as follows:

[0099] Step a: Use coarse sandpaper to roughly grind the mounted sample, wherein the sample needs to be cooled with water to prevent the sample from overheating.

[0100] During the implementation, the sample is ground with P180 mesh sandpaper, P600 mesh sandpaper, and P1200 mesh sandpaper in turn until it reaches the detection position. The grinding process should be cooled with water. If the plated hole is detected, the 600 mesh grinding should be ground to the center of the plated hole. The grinding speed usually used is 200-300rpm. When grinding with sandpapers of different meshes, the sample should be rotated 90° to completely remove the previous rough grinding marks. Whether the grinding marks are removed should be checked with a microscope. If there are grinding marks perpendicular to the last one on the sample, it means that the sample is not ground flat and should be reworked. Among them, the grinding marks produced by 180 mesh sandpaper are deeper and easy to damage the sample. You can use 600 mesh sandpaper to grind for a longer time, and then use 1200 mesh sandpaper to grind finely to the detection position. Rinse with running water and blow dry with dry air for observation.

[0101] Step b: perform the first rough polishing on the sample.

[0102] In practice, use 6μm polycrystalline diamond polishing liquid and hard, short-napped or lint-free polishing cloth for rough polishing, use a microscope to confirm whether the wear marks of 1200-grit sandpaper are completely removed, and ultrasonic cleaning can be used to clean the sample if necessary. Usually, medium pressure is used to polish the sample, and it takes 1 to 2 minutes to remove the upper wear marks. The rotation speed is generally 200 to 300rpm.

[0103] Step c: perform a second rough polishing on the sample.

[0104] In practice, use 3μm polycrystalline diamond polishing liquid and hard, short-neck or lint-free polishing cloth for rough polishing. Use a microscope to confirm whether the 6μm wear mark is completely removed. If necessary, the sample can be cleaned ultrasonically.

[0105] Step d: finely polish the sample.

[0106] During the implementation, the final polishing is performed using a soft, woven or medium fleece polishing cloth and a 1μm diamond polishing solution or a 0.05μm aluminum oxide suspension. The final polishing uses light or medium pressure, takes about 10-20 seconds, and the speed should be reduced to 100-150rpm. Rinse with running water, spray with alcohol and then blow dry with dry air.

[0107] like Figure 2 As shown, this embodiment also provides a specific implementation process of SEM sample preparation, as shown below:

[0108] Step 200, sampling and fixing of samples;

[0109] Among them, precise micro-sampling tools are used to take out the required samples from electronic components, usually in the range of micrograms to milligrams. The taken samples are placed on a metal or carbon sample table with micron-level flatness, and non-contact optical fixing methods such as light-curing resin or photon sintering technology are used to ensure that the samples are stable and do not move during subsequent processing.

[0110] Step 201, sample cleaning;

[0111] The fixed samples were placed in a mixed solution of deionized water and mild non-ionic surfactants, and cleaned with low-frequency ultrasonic waves for 5-10 minutes to remove dust and oil on the surface. Subsequently, a mixture of ethanol and acetone was used to effectively further clean the residual organic pollutants on the surface while dehydrating, and then dried with pure nitrogen gas immediately after slight shaking.

[0112] Step 202: Conductive treatment of the sample;

[0113] Since trace materials may not be able to directly conduct charges, a metal film with a thickness of 5-10 nanometers needs to be deposited on the surface of the sample to enhance conductivity. An ion sputtering coating machine is used to perform metal spraying in a vacuum environment to ensure that the film uniformly and continuously covers the entire sample surface.

[0114] Step 203: Precise cutting and polishing of the sample;

[0115] The samples were cut slowly using a precision cutting machine equipped with a diamond blade to avoid thermal damage and changes in the internal structure caused by mechanical stress. The cut samples were then manually polished on a special polishing cloth using micro-particle abrasive paste until the cross section reached a mirror finish with no obvious scratches.

[0116] Step 204: Sample preparation for SEM observation;

[0117] Among them, the fully prepared sample is placed in the SEM sample chamber, and after vacuuming, a preliminary low-magnification observation is carried out to check the overall morphology and approximate area of ​​the sample. After adjusting the working distance, focus and brightness, and determining the optimal observation conditions, detailed analysis and recording at high magnification are carried out.

[0118] In practice, the scanning electron microscope sample preparation method of this embodiment can highly retain the original state of trace materials through a non-contact optical fixation method, avoiding the risks brought by traditional physical contact fixation; through low-frequency ultrasonic cleaning, dehydration using a mixture of ethanol and acetone, and drying with inert gas, surface pollutants can be effectively removed without introducing new pollution sources, thereby ensuring the authenticity of the analysis results; this embodiment can also reduce the sample preparation cost, simplify the operation steps, and shorten the sample preparation cycle through the use of microparticle grinding paste. The sample preparation method of this embodiment has strong adaptability, and specific parameters can be adjusted according to different types of trace materials to minimize the loss and contamination of samples during the preparation process, while improving processing efficiency and imaging quality.

[0119] At present, more and more servers are using liquid cooling for heat dissipation. The purity of the coolant has a great impact on the overall operation of the server. At the same time, suspended matter is often found in the coolant. It is very important to know how to detect it, determine its source, and infer whether there is a problem with the overall operation. Placing tiny samples directly in the electron microscope for observation is likely to affect the electron microscope itself and affect the detection effect.

[0120] like Figure 3A-3B As shown, this embodiment provides a sample schematic diagram, wherein Figure 3B The magnification ratio Figure 3A The magnification is greater. Take the suspended matter in the coolant of the server as an example. First, use a micro-sampling tool to extract the suspended matter from the coolant of the server as a sample, use a non-contact optical fixation method to fix the sample, use low-frequency ultrasonic cleaning sample, and use a mixture of ethanol and acetone to dehydrate the sample. The residual contaminants on the surface of the sample can be cleaned. When there are more residues, the electron beam of the SEM electron microscope will cause the contaminants to volatilize when hitting the sample, affecting the electron microscope equipment itself, and easily causing damage to the electron microscope in the long run. When observing large block objects, in order to ensure that the surface oxide layer does not affect the detection error; the sample can also be polished to expose the center position, and the center position of the sample can be detected to finally get the desired result.

[0121] Based on the same inventive concept, an embodiment of the present invention also provides a scanning electron microscope sample preparation system. Since the system is the system in the method in the embodiment of the present invention, and the principle of solving the problem by the system is similar to that of the method, the implementation of the system can refer to the implementation of the method, and the repeated parts will not be repeated.

[0122] like Figure 4 As shown, the system includes:

[0123] A sample fixing device 400 is used to extract a sample from an electronic component and fix the sample using an optical fixing method, wherein the optical fixing method is used to fix the sample in a non-contact manner;

[0124] The sample cleaning device 401 is used to place the fixed sample in the first mixed solution, use low-frequency ultrasonic cleaning for a preset time to remove pollutants on the sample surface, and obtain a cleaned sample;

[0125] The sample drying device 402 is used to dehydrate the cleaned sample using a second mixed solution and blow dry it using an inert gas so as to enable the scanning electron microscope to detect it; wherein the inert gas is used to slow down the oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

[0126] As an optional implementation, the optical fixing method includes light-curing resin or photon sintering technology.

[0127] As an optional implementation, the inert gas includes nitrogen or argon.

[0128] As an optional embodiment, the system further includes a spraying device, which is specifically used for:

[0129] Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

[0130] As an optional embodiment, the system further comprises a cutting device, specifically used for:

[0131] The dried samples were cut using a cutting machine equipped with a diamond blade;

[0132] The cut samples are polished using micro-particle abrasive paste until the cut section reaches the preset effect.

[0133] Based on the same inventive concept, an embodiment of the present invention also provides a scanning electron microscope sample preparation device. Since the device is the device in the method in the embodiment of the present invention, and the principle of solving the problem by the device is similar to that of the method, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0134] like Figure 5 As shown, the device comprises:

[0135] The sample fixing module 500 is used to extract samples from electronic components and fix the samples using an optical fixing method, wherein the optical fixing method is used to fix the samples in a non-contact manner;

[0136] The sample cleaning module 501 is used to place the fixed sample in the first mixed solution and use low-frequency ultrasonic cleaning for a preset time to remove pollutants on the sample surface to obtain a cleaned sample;

[0137] The sample drying module 502 is used to dehydrate the cleaned sample using a second mixed solution and blow dry it using an inert gas so as to enable the scanning electron microscope to detect it; wherein the inert gas is used to slow down the oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

[0138] As an optional implementation, the optical fixing method includes light-curing resin or photon sintering technology.

[0139] As an optional implementation, the inert gas includes nitrogen or argon.

[0140] As an optional implementation, the device further includes a conductive module, specifically used for:

[0141] Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

[0142] As an optional embodiment, the device further includes a cutting and polishing module, which is specifically used for:

[0143] The dried samples were cut using a cutting machine equipped with a diamond blade;

[0144] The cut samples are polished using micro-particle abrasive paste until the cut section reaches the preset effect.

[0145] Based on the same inventive concept, an embodiment of the present disclosure provides a computer storage medium, the computer storage medium includes: a computer program code, when the computer program code is run on a computer, the computer executes any of the scanning electron microscope sample preparation methods discussed above. Since the principle of solving the problem by the above computer storage medium is similar to that of the scanning electron microscope sample preparation method, the implementation of the above computer storage medium can refer to the implementation of the method, and the repeated parts will not be repeated.

[0146] In the specific implementation process, the computer storage medium may include: Universal Serial Bus Flash Drive (USB), mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, and other storage media that can store program codes.

[0147] Based on the same inventive concept, the embodiment of the present disclosure further provides a computer program product, which includes: computer program code, when the computer program code is run on a computer, the computer executes any of the scanning electron microscope sample preparation methods discussed above. Since the principle of solving the problem by the above computer program product is similar to that of the scanning electron microscope sample preparation method, the implementation of the above computer program product can refer to the implementation of the method, and the repeated parts will not be repeated.

[0148] The computer program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more conductors, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0149] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program code.

[0150] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that has the functions specified in one or more boxes.

[0151] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0152] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0153] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a sample for a scanning electron microscope, characterized in that: The method includes: Extracting a sample from an electronic component and fixing the sample using an optical fixing method, wherein the optical fixing method is used to fix the sample in a non-contact manner; The fixed sample is placed in the first mixed solution, and low-frequency ultrasonic cleaning is performed for a preset time to remove pollutants on the surface of the sample to obtain a cleaned sample; The cleaned sample is dehydrated using a second mixed solution and blown dry using an inert gas so as to be detected by a scanning electron microscope; wherein the inert gas is used to slow down oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

2. The method according to claim 1, characterized in that The optical fixing method includes light-curing resin or photon sintering technology.

3. The method according to claim 1, characterized in that The inert gas includes nitrogen or argon.

4. The method according to claim 1, characterized in that: The method further includes: Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

5. The method according to claim 1, characterized in that The method further includes: The dried samples were cut using a cutting machine equipped with a diamond blade; The cut samples are polished using micro-particle abrasive paste until the cut section reaches the preset effect.

6. A scanning electron microscope sample preparation system, characterized in that: The system includes: A sample fixing device, used for extracting a sample from an electronic component, and fixing the sample using an optical fixing method, wherein the optical fixing method is used for non-contact fixing of the sample; A sample cleaning device, used to place the fixed sample in the first mixed solution, use low-frequency ultrasonic cleaning for a preset time to remove pollutants on the sample surface, and obtain a cleaned sample; The sample drying device is used to dehydrate the cleaned sample using a second mixed solution and blow dry it using an inert gas so that the scanning electron microscope can detect it; wherein the inert gas is used to slow down the oxidation of the sample, and the second mixed solution includes a mixed solution of ethanol and acetone.

7. The system according to claim 6, characterized in that The optical fixing method includes light-curing resin or photon sintering technology.

8. The system according to claim 6, characterized in that The inert gas includes nitrogen or argon.

9. The system according to claim 6, characterized in that The system also includes a spraying device, which is specifically used for: Metal spraying is performed on the dry sample in a vacuum environment, and the uniformity of the sprayed metal film on the sample surface is controlled by changing the vacuum degree in the vacuum environment.

10. The system according to claim 6, characterized in that The system also includes a cutting device, specifically for: The dried samples were cut using a cutting machine equipped with a diamond blade; The cut samples are polished using micro-particle abrasive paste until the cut section reaches the preset effect.

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