Sample table for scanning electron microscope liquid sample test

Abstract

The utility model discloses a sample table for testing a liquid sample of a scanning electron microscope. The sample table comprises a base, a cushion block, a sealing cover with an observation window and a top cover with an observation hole, the observation window and the observation hole are coaxially arranged; an accommodating groove is formed in the base; the cushion block and the containing groove are coaxially arranged, the cushion block is located in the containing groove, a sample groove is formed in the cushion block, and a liquid sample is contained in the sample groove; the sealing cover is arranged on the sample groove and is in sealing connection with the sample groove; the top cover is fixedly connected with the base, and the inner surface of the top cover is connected with the surface of the sealing cover, so that the sealing cover is attached to the sample groove. According to the sample table for the scanning electron microscope liquid sample test, a liquid sample can be packaged in a closed space for high-resolution morphology observation, the problems of volatilization and fixation of the liquid sample are solved, the liquid sample can be placed in a conventional scanning electron microscope for observation, and the convenience of the liquid sample test is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of scanning electron microscopes, and discloses a sample stage for testing liquid samples of a scanning electron microscope. Background Art

[0002] Due to its large depth of field, simple sample preparation method, and the ability to be used in combination with other detectors, the scanning electron microscope has developed into an indispensable instrument in the fields of scientific research and industrial production. When observing liquid samples with a scanning electron microscope, there are some technical problems, such as: (1) The scanning electron microscope has high requirements for vacuum degree. During the vacuum pumping process, the liquid sample will volatilize, making it difficult to reach the required vacuum degree in the sample chamber; (2) After the liquid sample volatilizes or dries under vacuum conditions, it will cause distortion or inability to observe; (3) It is difficult for the electron beam to penetrate through a relatively thick liquid sample, thus affecting the observation and imaging effects; (4) The electron beam irradiation on the sample surface will cause the accumulation of surface charges, affecting the clarity and accuracy of the image; (5) It is difficult to fix and support the liquid sample in a vacuum environment, making it difficult to position and observe the sample.

[0003] To overcome the above problems, a scanning electron microscope that can control the air pressure in the sample chamber - environmental scanning electron microscope - was developed in the 1960s and has been widely used in the fields of materials, biology, physics, etc. due to its unique structural advantages. By adjusting parameters such as temperature, pressure, and relative humidity in the sample chamber of the environmental scanning electron microscope, the sample can be in a controllable environmental condition. Therefore, in the environmental scanning electron microscope, liquid samples can be directly observed without the need for conductive pretreatment of their surfaces, thus maintaining the intrinsic natural state of the samples and reflecting more real surface information. Although the environmental scanning electron microscope has been greatly improved compared with the traditional scanning electron microscope, there are still some technical barriers, such as difficult sample pretreatment and fixation, high requirements for the experimental environment, and easy formation of a water film on the sample surface. In addition, the environmental scanning electron microscope is expensive and has a small market inventory, restricting the convenience of liquid sample testing. Summary of the Invention

[0004] The purpose of this application is to provide a sample stage for testing liquid samples of a scanning electron microscope to solve the technical problems of difficult sample pretreatment and fixation, high requirements for the experimental environment, easy formation of a water film on the sample surface, and high price existing in the existing environmental scanning electron microscope.

[0005] The utility model provides a sample stage for testing liquid samples of a scanning electron microscope, including a base, a cushion block, a sealing cover with an observation window, and a top cover with an observation hole; the observation window and the observation hole are coaxially arranged;

[0006] A receiving groove is formed on the base;

[0007] The spacer is coaxially arranged with the receiving groove and is located within the receiving groove. A sample groove is formed on the spacer, and a liquid sample is contained within the sample groove;

[0008] The sealing cover is arranged on the sample groove and is sealingly connected to the sample groove;

[0009] The top cover is fixedly connected to the base, and the inner surface of the top cover is in contact with the surface of the sealing cover for attaching the sealing cover to the sample groove.

[0010] Preferably, a liquid pool and a sealing groove surrounding the liquid pool are formed on the sample groove;

[0011] The liquid pool is used for containing the liquid sample;

[0012] A sealing ring is arranged within the sealing groove;

[0013] The sealing cover is in contact with the sealing ring.

[0014] Preferably, the thickness of the sealing ring is greater than the height of the sealing groove.

[0015] Preferably, the observation window is a silicon nitride observation window.

[0016] Preferably, positioning holes are formed on the receiving groove;

[0017] Positioning posts matching the positioning holes are arranged on the lower surface of the spacer;

[0018] The positioning posts extend into the positioning holes.

[0019] Preferably, the top cover includes a cover body with an observation hole and a hollow connecting column arranged on the lower surface of the cover body;

[0020] The hollow connecting column extends into the base and is fixedly connected to the base;

[0021] The spacer extends into the hollow connecting column, and the sealing cover arranged on the top of the spacer is in contact with the inner surface of the cover body.

[0022] Preferably, the hollow connecting column is threadedly connected to the base.

[0023] Preferably, the shape of the observation hole is a funnel shape with a larger upper diameter and a smaller lower diameter, and the minimum aperture of the observation hole is greater than or equal to the aperture of the observation window.

[0024] Preferably, knurling is arranged on the outer sides of both the base and the top cover.

[0025] Preferably, the materials of the base, the spacer, and the top cover are all conductive materials.

[0026] The sample stage for liquid sample testing of a scanning electron microscope according to the present utility model has the following beneficial effects compared with the prior art:

[0027] The sample stage for liquid sample testing of a scanning electron microscope according to the present utility model can encapsulate the liquid sample in a closed space for high-resolution morphology observation. It not only solves the problems of volatilization and fixation of liquid samples, but also can be placed in a conventional scanning electron microscope for observation, greatly improving the convenience of liquid sample testing. Description of the Drawings

[0028] Figure 1 It is a schematic diagram of the overall structure of the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0029] Figure 2 It is a front view schematic diagram of the disassembly of the overall structure of the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0030] Figure 3 It is a cross-sectional schematic diagram of the spacer block in the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0031] Figure 4 It is a three-dimensional view of the base in the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0032] Figure 5 It is a three-dimensional view of the top cover in the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0033] Figure 6 It is a scanning electron microscope image of hollow glass microspheres in an aqueous solution with a magnification of 500× measured by using the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0034] Figure 7 It is a scanning electron microscope image of hollow glass microspheres in an aqueous solution with a magnification of 1000× measured by using the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0035] Figure 8 It is a scanning electron microscope image of hollow glass microspheres in an aqueous solution with a magnification of 2000× measured by using the sample stage for liquid sample testing of a scanning electron microscope according to an embodiment of the present utility model.

[0036] List of components and reference numerals:

[0037] 1 is the base; 1-1 is the receiving groove; 1-2 is the positioning hole; 2 is the spacer block; 2-1 is the positioning post; 2-2 is the liquid pool; 2-3 is the sealing ring; 2-4 is the sealing cover; 3 is the top cover; 3-1 is the cover body; 3-2 is the hollow connecting column. Detailed implementation manners

[0038] In the following description, for the purpose of illustration rather than limitation, specific details such as specific system structures, technologies, etc. are presented to thoroughly understand the embodiments of the present utility model. However, those skilled in the art should clearly understand that the present utility model can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present utility model.

[0039] The present utility model provides a sample stage for testing liquid samples in a scanning electron microscope, as Figures 1 to 5 shown, which includes a base 1, a spacer 2, a sealed cover 2-4 with an observation window, and a top cover 3 with an observation hole; the observation window and the observation hole are coaxially arranged;

[0040] Among them, the structure of the base 1 is as Figure 4 shown. A receiving groove 1-1 is formed on the base 1. The lower surface of the base is a plane, and the assembled sample stage can be fixed on the sample holder of the scanning electron microscope with a conductive tape;

[0041] The structure of the spacer 2 is as Figure 3 shown. The spacer 2 is coaxially arranged with the receiving groove 1-1 and is located in the receiving groove 1-1. A sample groove is formed on the spacer 2, and a liquid sample is contained in the sample groove;

[0042] The sealed cover 2-4 is arranged on the sample groove and is hermetically connected to the sample groove;

[0043] The structure of the top cover 3 is as Figure 5 shown. The top cover 3 is fixedly connected to the base 1, and the inner surface of the top cover 3 is in contact with the surface of the sealed cover 2-4, which is used to make the sealed cover 2-4 adhere to the sample groove.

[0044] Through the cooperation of the top cover 3 and the base 1 of the sample stage of the present utility model, the sealed cover 2-4 is tightly attached to the sample groove, thereby realizing the sealing of the liquid sample and avoiding leakage in a high-vacuum environment, so as to realize the observation of the liquid sample using a scanning electron microscope. At the same time, the sample stage of the present utility model can realize the replacement of the sample outside the electron microscope. After replacement, it is fixed to the sample holder, which can greatly shorten the time for replacing the sample. The sample stage of the present utility model has the advantages of simple structure and small size, and can be installed and used in various models of scanning electron microscopes.

[0045] To improve the sealing effect of the liquid sample, in the embodiment of the present utility model, a liquid pool 2-2 and a sealing groove surrounding the liquid pool 2-2 are formed on the sample groove; the liquid pool 2-2 is used to hold the liquid sample; a sealing ring 2-3 is arranged in the sealing groove; the sealed cover 2-4 is in contact with the sealing ring 2-3, thereby sealing the liquid sample in the liquid pool 2-2.

[0046] The thickness of the sealing ring 2-3 in the embodiment of the present utility model is greater than the height of the sealing groove, so as to achieve close contact between the sealing ring 2-3 and the sealing cover 2-4.

[0047] In order to clearly observe the morphology of the liquid sample, the observation window in the embodiment of the present utility model is a silicon nitride observation window, and the thickness of the silicon nitride observation window is 20-200 nm. The thickness range of this silicon nitride observation window has good penetrability for electronic signals, so the morphology of the liquid sample can be clearly observed.

[0048] In order to further improve the tightness of the connection between the sealing cover 2-4 and the sealing ring 2-3, the top cover 3 in the embodiment of the present utility model includes a cover body 3-1 with an observation hole and a hollow connecting column 3-2 arranged on the lower surface of the cover body 3-1; the hollow connecting column 3-2 extends into the base 1 and is fixedly connected to the base 1, and the cushion block 2 extends into the hollow connecting column 3-2. Thus, while the top cover 3 is connected to the base 1, the inner surface of the cover body 3-1 tightly and stably presses the sealing cover 2-4 on the sealing ring 2-3, greatly improving the sealing effect. At this time, the height of the cushion block 2 is consistent with the depth of the receiving groove 1-1. After the cushion block 2 is placed in the receiving groove 1-1, it is flush with the top of the base, and the diameter of the cushion block 2 is smaller than the diameter of the receiving groove 1-1, so that the top cover can be screwed into the receiving groove 1-1.

[0049] In the embodiment of the present utility model, the fixed connection manner between the hollow connecting column 3-2 and the base 1 can be snap connection or threaded connection. Since the stability of threaded connection is better, the present utility model preferably uses threaded connection.

[0050] In order to realize the coaxial setting of the cushion block 2 and the receiving groove 1-1 opened on the base 1 and facilitate flexible disassembly and assembly, a positioning hole 1-2 is opened on the receiving groove 1-1 in the embodiment of the present utility model. The diameter of the positioning hole 1-2 is smaller than the diameter of the receiving groove 1-1, so that the receiving groove 1-1 can carry the cushion block. A positioning post 2-1 matching the positioning hole 1-2 is arranged on the lower surface of the cushion block 2 in the embodiment of the present utility model; the positioning post 2-1 extends into the positioning hole 1-2.

[0051] In order to facilitate the taking of the base 1 and the top cover 3 during the disassembly and assembly process, knurling is provided on the outer sides of the base 1 and the top cover 3 in the embodiment of the present utility model.

[0052] To solve the problem that the surface charge accumulation caused by electron beam irradiation on the surface of the liquid sample affects the clarity and accuracy of the image, the materials of the base 1, the spacer 2, and the top cover 3 in the embodiments of the present utility model are all made of conductive materials. Exemplarily, the conductive material can be aluminum alloy, copper alloy, etc. Since aluminum alloy has the advantages of light weight, high strength, good electrical conductivity, and low price, therefore, the embodiments of the present utility model preferably use aluminum alloy, which can timely conduct the charges in the liquid sample, improve the clarity and accuracy of the obtained image, and further enable the sample stage prepared by it to have the advantages of light weight, good electrical conductivity, long service life, and low cost.

[0053] The shape of the observation hole in the embodiments of the present utility model is a funnel shape with a larger upper part and a smaller lower part, and the minimum aperture of the observation hole is greater than or equal to the aperture of the observation window, so as to facilitate observing the morphology of the liquid sample.

[0054] The method for testing a liquid sample in a scanning electron microscope using the sample stage of the embodiments of the present utility model is as follows:

[0055] 1) Place the spacer 2 in the receiving groove 1-1 on the base 1 and connect it with the positioning hole 1-2 on the base 1 through the positioning post 2-1, and place the sealing ring 2-3 in the sealing groove;

[0056] 2) Use a pipette to suck an appropriate amount of the liquid sample to be observed, and drop the liquid sample into the liquid cell 2-2;

[0057] 3) Place the sealing cover 2-4 into the sample groove at the upper end of the spacer 2 and place it on the sealing ring 2-3;

[0058] 4) Screw the top cover 3 into the receiving groove 1-1 on the base 1, so that the sealing cover 2-4 seals the liquid sample in the liquid cell 2-2;

[0059] 5) Open the sample chamber of the scanning electron microscope, and use a conductive tape to fix the assembled sample stage on the sample holder of the scanning electron microscope;

[0060] 6) Close the sample chamber of the scanning electron microscope. After the vacuum degree of the sample chamber reaches the requirement, the liquid sample can be tested;

[0061] 7) After the test is completed, vent the sample chamber of the scanning electron microscope, and open the sample chamber to replace the sample or remove the sample stage device.

[0062] Figures 6 to 8 Figure Figures 6 to 8 is the scanning electron microscope image of hollow glass microspheres in an aqueous solution measured by the sample stage of the present utility model. It can clearly observe the shape, size, and distribution of the hollow glass microspheres in the aqueous solution, providing important reference and data support for further studying the characteristics and applications of hollow glass microspheres.

[0063] ​The sample stage of the present utility model can encapsulate liquid samples in a closed space for high-resolution topography observation, which not only solves the problems of volatilization and fixation of liquid samples, but also can be placed in a conventional scanning electron microscope for observation, greatly improving the convenience of liquid sample testing.

[0064] The above are only several embodiments of the present application, and do not impose any form of limitation on the present application. Although the present application is disclosed above with preferred embodiments, it is not intended to limit the present application. Any person skilled in the art, without departing from the scope of the technical solution of the present application, makes some changes or modifications using the technical content disclosed above, which are all equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A sample stage for liquid sample testing using a scanning electron microscope, characterized in that: It includes a base, a cushion block, a sealing cover with an observation window and a top cover with an observation hole; the observation window and the observation hole are coaxially arranged; The base is provided with a receiving groove; The pad is coaxially arranged with the receiving groove and is located in the receiving groove. The pad is provided with a sample groove, and the sample groove contains a liquid sample. The sealing cover is disposed on the sample groove and is sealed and connected to the sample groove; The top cover is fixedly connected to the base, and the inner surface of the top cover is in contact with the surface of the sealing cover, so that the sealing cover is attached to the sample groove.

2. The sample stage for liquid sample testing under a scanning electron microscope according to claim 1, characterized in that: The sample groove is provided with a liquid pool and a sealing groove surrounding the liquid pool; The liquid pool is used to hold liquid samples; A sealing ring is arranged in the sealing groove; The sealing cover is connected to the sealing ring.

3. The sample stage for liquid sample testing under a scanning electron microscope according to claim 2, characterized in that: The thickness of the sealing ring is greater than the height of the sealing groove.

4. The sample stage for liquid sample testing under a scanning electron microscope according to any one of claims 1 to 3, characterized in that: The top cover includes a cover body with an observation hole and a hollow connecting column arranged on the lower surface of the cover body; The hollow connecting column extends into the base and is fixedly connected to the base; The cushion block extends into the hollow connecting column, and the sealing cover arranged on the top of the cushion block is connected to the inner surface of the cover body.

5. The sample stage for liquid sample testing under a scanning electron microscope according to claim 4, characterized in that: The hollow connecting column is threadedly connected to the base.

6. The sample stage for liquid sample testing under a scanning electron microscope according to claim 1, characterized in that: The shape of the observation hole is a funnel shape that is larger at the top and smaller at the bottom, and the minimum aperture of the observation hole is greater than or equal to the aperture of the observation window.

7. The sample stage for liquid sample testing under a scanning electron microscope according to claim 1, characterized in that: The observation window is a silicon nitride observation window.

8. The sample stage for liquid sample testing under a scanning electron microscope according to claim 1, characterized in that: A positioning hole is provided on the receiving groove; The lower surface of the cushion block is provided with a positioning column matching the positioning hole; The positioning column extends into the positioning hole.

9. The sample stage for liquid sample testing under a scanning electron microscope according to claim 1, characterized in that: The outer sides of the base and the top cover are both provided with knurling.

10. The sample stage for liquid sample testing under a scanning electron microscope according to claim 1, characterized in that: The base, the cushion block and the top cover are all made of conductive materials.

Images