Sample preparation method of transparent plastic and analysis method of sample and internal foreign matter components

Abstract

The invention discloses a transparent plastic sample preparation method and a sample and internal foreign matter component analysis method. The sample preparation method comprises the following steps: determining the position of a foreign matter in a transparent plastic sample; polishing the sample surface of the foreign matter area to approach the foreign matter; and the ground sample is thinned in an ion thinning mode until the foreign matter is exposed. According to the transparent plastic sample preparation method, sample pollution can be avoided, and the accuracy of foreign matter analysis is improved.

Description

Technical Field

[0001] The present application relates to the technical field of component detection, and more specifically, to a method for preparing a sample of transparent plastic, and a method for analyzing the sample and the components of internal foreign matter. Background Art

[0002] Impurities or foreign matter inside transparent plastics will affect their use. Therefore, transparent plastics with impurities inside are usually tested and analyzed to confirm the source of the foreign matter, and then improvements are made in the process or production to improve the quality of the transparent plastics.

[0003] In the prior art, the sample is prepared by slicing, grinding and polishing. However, the slicing, grinding and polishing method is more likely to introduce grinding and polishing foreign matter, which affects the test results of the actual foreign matter composition. Summary of the invention

[0004] One purpose of the present application is to provide a new technical solution for a method for preparing a sample of a transparent plastic, and a method for analyzing the sample and the foreign matter components inside the sample.

[0005] According to a first aspect of the present application, a method for preparing a transparent plastic sample is provided, which is applied to the analysis of internal foreign matter components. The method comprises:

[0006] Confirm the location of foreign matter in transparent plastic samples;

[0007] Grind the sample surface in the area where the foreign matter is located until it is close to the foreign matter;

[0008] The polished sample was thinned by ion thinning until the foreign matter was exposed.

[0009] Optionally, the step of confirming the location of the foreign matter in the transparent plastic sample includes:

[0010] Use the ring light source of the ultra-depth-of-field microscope to focus and observe the inside of the sample to confirm the location of the foreign matter in the sample.

[0011] Optionally, polishing the sample surface in the area where the foreign matter is located until it is close to the foreign matter includes:

[0012] During the polishing process of the sample, the coaxial light source of the ultra-depth-of-field microscope is used to focus and observe the sample until the outline of the foreign matter can be observed, confirming that it is close to the foreign matter.

[0013] Optionally, when grinding close to the foreign object, the distance between the sample surface and the foreign object is less than 1 mm.

[0014] Optionally, use 1000# or 2000# sandpaper to grind the sample surface in the area where the foreign matter is located.

[0015] Optionally, during the process of thinning the sample, the morphology of the sample is observed by focusing using a coaxial light source of an ultra-depth-of-field microscope to confirm whether the sample is exposed.

[0016] Optionally, the polished sample is cut to a set size, fixed in a sample chamber of an ion thinning instrument, and cooled and thinned with liquid nitrogen.

[0017] According to a second aspect of the present application, a transparent plastic sample is provided, which is made by the sample preparation method described in the first aspect.

[0018] According to a third aspect of the present application, a method for analyzing foreign matter components inside a transparent plastic is provided, comprising: the sample preparation method described in the first aspect or the transparent plastic sample described in the second aspect.

[0019] Optionally, the surface of the sample where the foreign matter is exposed is sprayed with gold, and the composition of the foreign matter is analyzed using a scanning electron microscope.

[0020] According to an embodiment of the present application, the present application locates the foreign matter in the sample first, then polishes at the corresponding position, and finally thins the sample by ion thinning until the foreign matter is exposed, so as to facilitate the analysis of the foreign matter composition. This sample preparation method can avoid the introduction of polishing foreign matter caused by polishing, improve the accuracy of analysis, and can also improve the efficiency of sample preparation and reduce the production cost.

[0021] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0023] Figure 1 It is a flow chart of the sample preparation method of transparent plastic provided in this application.

[0024] Figure 2 This is a picture of observing foreign matter inside a transparent plastic using a ring light source provided in this application.

[0025] Figure 3 This is an observation picture of the coaxial light source provided in this application when the sample is polished to a point close to a foreign object.

[0026] Figure 4 This is an observation picture of the coaxial light source provided in this application when the sample is thinned to the point where foreign matter is exposed.

[0027] Among them: 1. Transparent plastic; 2. Foreign matter. DETAILED DESCRIPTION

[0028] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0029] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0030] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0031] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0032] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0033] In the prior art, for the analysis of foreign matter, the sample preparation is usually carried out by slicing, grinding and polishing. However, the slicing, grinding and polishing method is more likely to introduce grinding and polishing foreign matter, affecting the test results of the actual foreign matter composition.

[0034] According to a first aspect of the present application, a method for preparing a sample of a transparent plastic 1 is provided, which is applied to analyzing the composition of an internal foreign body 2. The method comprises:

[0035] First, confirm the location of the foreign matter 2 in the transparent plastic 1 sample, refer to Figure 1 S01 and Figure 2 .

[0036] In this step, the position of the foreign body 2 inside the sample can be confirmed by observation, for example, by human eye observation. After confirming the position of the foreign body 2, a preliminary mark can be made on the corresponding surface to facilitate subsequent operation procedures; precise preliminary marking can also be performed by focusing a microscope.

[0037] Secondly, grind the sample surface in the area where the foreign body 2 is located until it is close to the foreign body 2. Figure 1 S02 and Figure 3 .

[0038] In this step, the sample surface with the position of the foreign body 2 can be polished and ground manually or by machine by sandpaper or other polishing devices until the polishing is stopped when it is close to the foreign body 2. Wherein, whether it is close to the foreign body 2 can be judged by observing the distance between the foreign body 2 and the outer surface from the side of the sample, or by observing the clarity of the foreign body 2 from the polished surface. It is specifically implemented according to the actual convenience and all observation equipment, and this application does not limit this. It should be noted that the foreign body 2 needs to be observed continuously during the polishing process to ensure the safe distance between the foreign body 2 and the outer surface of the sample. Therefore, during the actual operation, the staff needs to stop the polishing action after polishing for a period of time and observe through a microscope at the same time, and as the polishing work proceeds, the polishing time becomes shorter and shorter to prevent mistakes caused by excessive polishing. If the clarity of the foreign body 2 is observed, it is also necessary to operate in a continuous intermittent manner, and the focal length of the microscope needs to be adjusted during the polishing process to further narrow the range of the foreign body 2 and ensure the accurate position of the foreign body 2 in the sample.

[0039] In the above steps, grinding is a process of thinning the sample surface. Directly grinding until the foreign body 2 is exposed can easily lead to the introduction of new foreign bodies. Grinding to a degree close to the foreign body 2 can increase the thinning speed of the sample on the one hand, and will not introduce new foreign bodies on the other hand, thus ensuring the accuracy of subsequent detection. In addition, during the grinding process, the position of the foreign body 2 in the transparent plastic 1 sample is observed at any time to ensure that it is ground to the appropriate position, avoiding excessive or inadequate grinding that affects the subsequent thinning process.

[0040] Finally, the polished sample was thinned by ion thinning until the foreign body 2 was exposed. Figure 1 S03 and Figure 4 .

[0041] In this step, the sample that has been polished to be close to the foreign body 2 is subjected to ion thinning, so that the foreign body 2 can be exposed from the transparent plastic 1 sample, so as to facilitate the subsequent composition analysis of the foreign body 2. Among them, ion thinning is a method of using an ion beam to bombard the sample surface in a high vacuum equipment cavity to achieve grinding and thinning. The thinning process is not affected by the electrical properties of the material, and a variety of materials can be thinned, with little pollution. The preparation process is relatively clean and will not introduce new foreign matter into the transparent plastic 1 sample.

[0042] In addition, after the foreign body 2 is exposed, the area of ​​the exposed portion can be controlled according to actual needs. Usually, the sample can be thinned until the maximum cross-section of the foreign body 2 is exposed, so as to facilitate subsequent cost detection and analysis of the foreign body 2.

[0043] To summarize, the present application adopts the method of first grinding and then ion thinning, while observing the morphology of foreign matter 2 in the sample during the process. This can not only avoid the introduction of new foreign matter caused by complete grinding, and process the sample relatively cleanly until the foreign matter 2 is exposed, but also avoid the problem of too low efficiency of ion thinning, thereby ensuring the accuracy of the foreign matter 2 composition of the produced sample, while improving the production efficiency, and providing a production method that is different from FIB (Focused Ion Beam, focused ion beam technology), providing the possibility of diversified choices for sample production methods, and reducing the production cost of the sample and the cost of testing and analyzing the composition of foreign matter 2.

[0044] Alternatively, if Figure 2 As shown, the confirmation of the location of the foreign matter 2 in the transparent plastic 1 sample includes: using the annular light source of the ultra-depth-of-field microscope to focus and observe the inside of the sample to confirm the location of the foreign matter 2 in the sample.

[0045] Specifically, in this embodiment, the location of the foreign body 2 in the transparent plastic 1 sample can be confirmed by observing the super-depth microscope. The super-depth microscope is a new type of microscope technology. The working principle of the super-depth microscope involves high-resolution imaging, super-depth imaging, optical phase modulation, etc.; high-resolution imaging refers to the use of a high numerical aperture objective and a high-sensitivity detector to obtain high-quality images; optical phase modulation refers to the imaging at different focal depths by changing the relative phase difference between the objective and the sample. The super-depth microscope uses a grating to diffract the incident light to image the object in space. Its working principle involves wavefront propagation technology, which improves the clarity and imaging ability of the microscope by controlling the wavefront phase difference. This technology can realize microscopic observation and analysis of cells, intracellular structures and biomolecules. When confirming the location of the foreign body 2, based on the advantages of the super-depth microscope such as high resolution, optical phase modulation and wide magnification range, the location of the foreign body 2 in the transparent plastic 1 sample can be quickly confirmed.

[0046] Furthermore, when using an ultra-depth-of-field microscope for observation, a ring light source can be used to focus on and observe the sample. The ring light source can provide a variety of different illumination angles and color options, and can provide uniform and stable lighting with high brightness. It can also enable the ultra-depth-of-field microscope to focus on the interior of the transparent plastic 1 sample, making the image of the foreign matter 2 clearer, which is conducive to improving the accuracy and efficiency of confirming the position of the foreign matter 2 in the sample.

[0047] Alternatively, if Figure 3 As shown, the polishing of the sample surface in the area where the foreign body 2 is located until it is close to the foreign body 2 includes: during the polishing process of the sample, focusing and observing the sample with the coaxial light source of the ultra-depth of field microscope until the outline of the foreign body 2 can be observed, confirming that it is close to the foreign body 2.

[0048] Specifically, during the process of polishing the sample surface, the polishing progress needs to be observed at any time to avoid excessive polishing that may expose the foreign body 2 and affect the analysis results. In this embodiment, by focusing on the sample with the coaxial light source of the ultra-depth of field microscope, the polishing progress can be judged according to the clarity of the outline of the foreign body 2. When the outline of the foreign body 2 is observed to be relatively clear, it can be confirmed that the foreign body 2 is approaching and the polishing is stopped, and the next step is carried out.

[0049] In the above embodiment, the coaxial light source is more accurate and clear in observing the sample surface. It can provide more uniform lighting than traditional light sources, help reduce reflections from objects, improve the accuracy and reproducibility of machine vision, and highlight the features of the object surface. Its color selection has little effect on contour imaging, making it more accurate to observe the contour of the foreign body 2 using the coaxial light source, thereby improving the accuracy of observation and judgment of the grinding depth.

[0050] Optionally, when polishing to approach the foreign object 2, the distance between the sample surface and the foreign object 2 is less than 1 mm.

[0051] Specifically, in practical applications, the judgment of approaching the foreign body 2 can also be made by observing or measuring the distance between the sample surface and the foreign body 2. When the distance between the sample surface and the foreign body 2 is observed to be less than 1 mm, it means that the foreign body 2 is about to be exposed from the sample surface. The subsequent use of ion thinning to expose it improves the thinning efficiency, avoids ion thinning consuming too much time, and reduces the thinning cost.

[0052] Optionally, use 1000# or 2000# sandpaper to grind the sample surface in the area where the foreign matter 2 is located.

[0053] Specifically, in this embodiment, the initial thinning of the sample is achieved by sandpaper thinning. Sandpaper polishing is a common surface treatment technology, which is more efficient and less expensive than ion thinning technology, and the thinning depth is easy to control. By combining sandpaper polishing and ion thinning to process the sample, sample contamination can be avoided and the sample thinning efficiency can be improved.

[0054] In practical applications, the mesh number of the sandpaper used for grinding is 1000# or 2000#, which can not only avoid the problem of low grinding efficiency caused by too low mesh number, but also take into account the fineness of the surface of the sample after grinding, making the surface after grinding smoother, which is conducive to the observation of the contour of foreign matter 2, avoiding over-deep grinding, and improving the accuracy of the grinding depth.

[0055] Alternatively, if Figure 4 As shown, during the thinning process of the sample, the coaxial light source of the ultra-depth-of-field microscope is used to focus and observe the morphology of the sample to confirm whether the sample is exposed.

[0056] Specifically, in this embodiment, by using the coaxial light source of the ultra-depth-of-field microscope to focus on observing the ion-thinned sample, the degree of exposure of the foreign matter 2 can be clearly observed, so as to control the area of ​​exposure of the foreign matter 2 and facilitate subsequent detection of a suitable foreign matter 2 component.

[0057] Optionally, the polished sample is cut to a set size, fixed in a sample chamber of an ion thinning instrument, and cooled and thinned with liquid nitrogen.

[0058] Specifically, in this embodiment, before the polished sample is subjected to the ion thinning process, the sample needs to be cut to a size that can be placed in a sample chamber of an ion thinning instrument, so as to facilitate the thinning process. The purpose of adding liquid nitrogen cooling during the ion thinning process is to avoid melting or deformation of the transparent plastic 1 due to high temperature, thereby ensuring the quality of sample preparation.

[0059] In one embodiment, when the sample is polished to within 1mm of the surface of the foreign matter, it is fixed to the flat polishing tooling, and the tooling and the sample are placed in the sample chamber of the ion thinning instrument at the same time. Liquid nitrogen is added to cool the sample, and the voltage is set to 5-10KV, and the time is 5-20min. The sample is thinned. Note that during the thinning process, the morphology of the polished sample needs to be observed in real time. After thinning and polishing to the sample position, use super-depth coaxial light to confirm the foreign matter 2, such as Figure 4 .

[0060] According to a second aspect of the present application, a transparent plastic 1 sample is provided, which is made by the sample preparation method described in the first aspect.

[0061] The sample is first observed by human eyes or microscope to preliminarily determine the location of the foreign matter, and circle it, then use 1000# or 2000# sandpaper to polish the sample surface in the area where the foreign matter is located. During the polishing process, multiple confirmations are required. The coaxial light source of the ultra-depth microscope is used to focus and observe the morphology of the sample to confirm whether the sample is exposed. At the same time, the coaxial light source focusing function of the ultra-depth microscope is used to observe the sample until the outline of the foreign matter can be observed and confirmed as close to the foreign matter. The ultra-depth microscope can reduce the sample surface to a distance of less than 1mm from the foreign matter, which is convenient for subsequent progress. After completing the first step, the polished sample is cut to a set size, fixed in the sample chamber of the ion thinning instrument, and cooled and thinned with liquid nitrogen. The voltage is set to 5~10KV, and the time is 5~20min. The sample is thinned. Note that during the thinning process, the morphology of the polished sample needs to be observed immediately. After thinning and polishing to the sample position, the ultra-depth coaxial light is used to confirm the situation of foreign matter 2 to obtain the product.

[0062] It should be noted that the above-mentioned liquid nitrogen cooling zone, voltage value, and power-on time can be set according to the actual operating environment, and this solution does not impose any restrictions on this.

[0063] Specifically, in this embodiment, the transparent plastic 1 sample provided is made by the sample preparation method of the first aspect. Since it is made by grinding and ion thinning, the analysis of the components of the exposed foreign matter 2 is more accurate, and the sample preparation efficiency is high and the cost is low, and it can be applied to batch testing.

[0064] According to a third aspect of the present application, a method for analyzing the composition of foreign matter 2 inside a transparent plastic 1 is provided, comprising: the sample preparation method described in the first aspect.

[0065] Specifically, in this embodiment, when sample preparation is required in the analysis method of the components of the foreign matter 2 inside the transparent plastic 1, the sample preparation method provided by the first aspect can be used. The sample preparation efficiency is high and sample contamination can be avoided, thereby improving the analysis efficiency and analysis accuracy of the analysis method.

[0066] Optionally, the surface of the sample where the foreign matter 2 is exposed is sprayed with gold, and the composition of the foreign matter 2 is analyzed using a scanning electron microscope.

[0067] Specifically, in the present embodiment, the scanning electron microscope spectrometer is a scanning electron microscope (SEM) + energy dispersive spectrometer (EDS). The scanning electron microscope (SEM) is a microscopic morphology observation method between the transmission electron microscope and the optical microscope, and can directly use the material properties of the sample surface material for microscopic imaging. It is an electron microscope that uses a high-energy focused electron beam to scan the sample surface, stimulates secondary electrons, backscattered electrons, X-rays and other information, and detects the corresponding detectors to obtain sample information. It is used to analyze the type and content of elements in the sample. The energy spectrometer detects the X-rays generated when the electron beam interacts with the sample, distinguishes various elements according to the difference in energy distribution, and calculates the relative content of each element. In this embodiment, gold is sprayed on the surface of the foreign matter 2 of the sample to facilitate the connection to the scanning electron microscope for operation.

[0068] In addition, the scanning electron microscope and the energy spectrometer can clearly present the morphology of the sample surface, and the energy spectrometer can be used for micro-region composition analysis to determine the surface morphology and composition type of the foreign body 2.

[0069] The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0070] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A method for preparing a transparent plastic sample, which is used for analyzing the composition of internal foreign matter, characterized in that: The sample preparation method comprises: Confirm the location of foreign matter in transparent plastic samples; Grind the sample surface in the area where the foreign matter is located until it is close to the foreign matter; The polished sample was thinned by ion thinning until the foreign matter was exposed.

2. The method for preparing a transparent plastic sample according to claim 1, characterized in that: The method of confirming the location of foreign matter in the transparent plastic sample comprises: Use the ring light source of the ultra-depth-of-field microscope to focus and observe the inside of the sample to confirm the location of the foreign matter in the sample.

3. The method for preparing a transparent plastic sample according to claim 1, characterized in that: The grinding of the sample surface in the area where the foreign matter is located until it is close to the foreign matter includes: During the polishing process of the sample, the coaxial light source of the ultra-depth-of-field microscope is used to focus and observe the sample until the outline of the foreign matter can be observed, confirming that it is close to the foreign matter.

4. The method for preparing a transparent plastic sample according to claim 3, characterized in that: When grinding close to the foreign object, the distance between the sample surface and the foreign object is less than 1 mm.

5. The method for preparing a transparent plastic sample according to claim 1, characterized in that: Use 1000# or 2000# sandpaper to grind the sample surface where the foreign matter is located.

6. The method for preparing a transparent plastic sample according to claim 1, characterized in that: During the thinning process of the sample, the coaxial light source of the ultra-depth-of-field microscope is used to focus and observe the morphology of the sample to confirm whether the sample is exposed.

7. The method for preparing a transparent plastic sample according to claim 6, characterized in that: After the polished sample is cut to the set size, it is fixed in the sample chamber of the ion thinning instrument and cooled and thinned with liquid nitrogen.

8. A transparent plastic sample, characterized in that: The sample is prepared by the sample preparation method according to any one of claims 1 to 7.

9. A method for analyzing foreign matter components inside transparent plastic, characterized in that: include: The sample preparation method according to any one of claims 1 to 7, or the transparent plastic sample according to claim 8.

10. The analysis method according to claim 9, characterized in that: The surface of the sample where the foreign matter was exposed was sprayed with gold, and the foreign matter composition was analyzed using a scanning electron microscope.

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