Detection system

Abstract

The detection system comprises an objective table, a detector and a filter plate, and the objective table is used for bearing a sample; the detector and the objective table are arranged at an interval in the first direction, and the detector is used for collecting signal electrons emitted by the sample; the filter plate is located between the objective table and the detector, at least one first through hole penetrating through the filter plate in the first direction is formed in the filter plate, and the orthographic projection of the first through hole on the objective table and the orthographic projection of the detector on the objective table are at least partially overlapped. A filter plate is arranged between an objective table and a detector, a first through hole is formed in the filter plate, the first through hole and the detector are at least partially overlapped, one part of signal electrons emitted by a sample are blocked by the filter plate, and the other part of the signal electrons pass through the first through hole and are collected by the detector, so that the current collected by the detector becomes smaller; the saturation current threshold value of the detector is improved in a disguised manner, so that the electron gun can emit a stronger detection beam to the sample on the objective table, and the detection effect of the detection system on the sample is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of integrated circuit manufacturing, and in particular to a detection system. Background Art

[0002] An integrated circuit is a miniature electronic device or component. Using a certain process, the transistors, resistors, capacitors, inductors and other components and wiring required in a circuit are interconnected and made on a small piece or several small pieces of semiconductor wafers or dielectric substrates, and then packaged in a tube shell to become a miniature structure with the required circuit function. The processing process of its core components is very complicated, involving multiple procedures, and it is necessary to monitor electrical properties, dimensions, defects, etc. at all times.

[0003] In the related technology, a scanning electron microscope is used to detect the yield of wafers. The principle is that the scanning electron microscope emits a detection beam, and the wafer emits signal electrons after being irradiated by the detection beam. The detector then collects the signal electrons and analyzes the data to reflect the morphology and electrical defects of the wafer surface.

[0004] In order to improve the detection effect of wafer defects, the current of the detection beam emitted by the scanning electron microscope can be increased. However, the larger the current of the detection beam, the larger the current of the signal electron. When the current of the signal electron exceeds the saturation current of the detector, it will cause the detector to be overexposed, resulting in detection failure. Summary of the invention

[0005] The embodiments of the present application provide a detection system, aiming to improve the detection effect of samples.

[0006] An embodiment of the present application provides a detection system, including a stage, an electron gun, a detector and a filter plate, wherein the stage is used to carry samples; the detector and the stage are spaced apart along a first direction, and the detector is used to collect signal electrons emitted by the samples; the filter plate is located between the stage and the detector, and the filter plate is provided with at least one first through hole penetrating the filter plate along the first direction, and an orthographic projection of the first through hole on the stage at least partially overlaps with an orthographic projection of the detector on the stage.

[0007] According to the implementation scheme of the first aspect of the present application, it also includes an electron gun, which is located on the side of the detector away from the filter plate, and generates a detection beam toward the stage when the electron gun is started; a second through hole is also provided on the filter plate that penetrates the filter plate along the first direction, and the orthographic projection of the detection beam emitted by the electron gun on the stage overlaps with the orthographic projection of the second through hole on the stage or is located within the orthographic projection of the second through hole on the stage.

[0008] According to the implementation scheme of the first aspect of the present application, the diameter of the detection beam is less than or equal to 0.5 mm; when the shape of the second through hole is circular, the diameter of the second through hole is greater than or equal to 0.5 mm, and less than or equal to 2.5 mm; when the shape of the second through hole is square, the side length of the second through hole is greater than or equal to 0.5 mm, and less than or equal to 2.5 mm.

[0009] According to an implementation of the first aspect of the present application, a plurality of first through holes are arranged around the second through hole.

[0010] According to an implementation of the first aspect of the present application, the orthographic projections of the first through holes on the stage are all located within the orthographic projections of the detector on the stage.

[0011] According to the implementation scheme of the first aspect of the present application, the spacing between adjacent first through holes gradually increases in the direction away from the second through hole; and / or, in the radial direction of the filter plate and in the direction away from the second through hole, the radial size of the first through hole gradually increases; and / or, in the radial direction of the filter plate, the filter plate includes a first area and a second area, the first area is arranged around the second through hole, the second area is arranged around the first area, and the radial size of the first through hole located in the second area is larger than the radial size of the first through hole located in the first area.

[0012] According to an implementation of the first aspect of the present application, a plurality of first through holes are arranged in rows and columns.

[0013] According to an implementation of the first aspect of the present application, the shape of the second through hole includes at least one of a circle, an ellipse, and a polygon, and the shape of the first through hole includes at least one of a circle, an ellipse, a polygon, and a fan ring.

[0014] According to the implementation scheme of the first aspect of the present application, the shape of the first through holes is a square, the side length of the first through holes is greater than or equal to 0.2 mm and less than or equal to 1.2 mm; the spacing between adjacent first through holes is greater than or equal to 0.1 mm and less than or equal to 0.7 mm.

[0015] According to the implementation scheme of the first aspect of the present application, the second through hole is circular in shape, and the first through hole is fan-shaped surrounding the second through hole; the central angle of the fan-shaped ring of the first through hole is greater than or equal to 5° and less than or equal to 9°.

[0016] The detection system of the embodiment of the present application is provided with a filter plate between the stage and the detector, and at least one first through hole is provided on the filter plate, and the first through hole and the detector are at least partially overlapped. A part of the signal electrons emitted by the sample is blocked by the filter plate, and another part passes through the first through hole and is collected by the detector, so that the current collected by the detector becomes smaller, thereby increasing the saturation current threshold of the detector in disguise, thereby allowing the electron gun to emit a stronger detection beam to the sample on the stage, thereby improving the detection effect of the detection system on the sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 A cross-sectional schematic diagram of a detection system according to some embodiments of the present application;

[0019] Figure 2 One of the schematic diagrams of the top view of an exemplary filter plate is shown;

[0020] Figure 3 A second schematic diagram showing a top view of an exemplary filter plate;

[0021] Figure 4 A third schematic diagram showing a top view of an exemplary filter plate;

[0022] Figure 5 A fourth schematic diagram showing a top view of an exemplary filter plate;

[0023] Figure 6 A fifth schematic diagram showing a top view of an exemplary filter plate;

[0024] Figure 7 A sixth schematic diagram showing a top view of a filter plate according to an example;

[0025] Figure 8 FIG7 is a schematic diagram showing a top view of an exemplary filter plate.

[0026] Reference numerals:

[0027] 10. Detection system; 11. Sample;

[0028] 100. Stage;

[0029] 200. Electron gun;

[0030] 300, detector; 310, third through hole;

[0031] 400, filter plate; 410, first through hole; 420, second through hole; 430, connecting rib; 440, reinforcing rib; 450, first area; 460, second area;

[0032] 500, deflector; 600, objective lens; 700, booster;

[0033] x, first direction. DETAILED DESCRIPTION

[0034] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0035] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0036] In order to solve the defects mentioned in the background technology, the present application provides a detection system, including a stage, an electron gun, a detector and a filter plate, the stage is used to carry samples; the detector and the stage are arranged with an interval along a first direction, and the detector is used to collect signal electrons emitted by the sample; the filter plate is located between the stage and the detector, and the filter plate is provided with at least one first through hole penetrating the filter plate along the first direction, and the orthographic projection of the first through hole on the stage at least partially overlaps with the orthographic projection of the detector on the stage.

[0037] The detection system provided in the present application is provided with a filter plate between the stage and the detector, at least one first through hole is provided on the filter plate, and the first through hole and the detector are at least partially overlapped, so that a part of the signal electrons emitted by the sample are blocked by the filter plate, and the other part passes through the first through hole and is collected by the detector, so that the current collected by the detector becomes smaller, thereby increasing the saturation current threshold of the detector in disguise, thereby enabling the electron gun to emit a stronger detection beam to the sample on the stage, thereby improving the detection effect of the detection system on the sample.

[0038] In order to better understand the present application, the detection system provided by the present application is described below in conjunction with the accompanying drawings. It is noted that the x direction in the accompanying drawings is the first direction. In the accompanying drawings, for the convenience of drawing, the dimensions in the drawings are not necessarily proportional to the actual dimensions.

[0039] Please refer to Figure 1 and Figure 2 , Figure 1 A cross-sectional schematic diagram of a detection system according to some embodiments of the present application; Figure 2 One of the schematic diagrams of the top view of an exemplary filter plate is shown.

[0040] like Figure 1 and Figure 2 As shown, the embodiment of the present application provides a detection system 10, including a stage 100, a detector 300 and a filter plate 400, wherein the stage 100 is used to carry a sample 11. The detector 300 and the stage 100 are spaced apart along a first direction (the x direction in the figure), and the detector 300 is used to collect signal electrons emitted by the sample 11. The filter plate 400 is located between the stage 100 and the detector 300, and the filter plate 400 is provided with at least one first through hole 410 that penetrates the filter plate 400 along the first direction x, and the orthographic projection of the first through hole 410 on the stage 100 at least partially overlaps with the orthographic projection of the detector 300 on the stage 100.

[0041] Optionally, sample 11 is a wafer.

[0042] Optionally, the detector 300 is provided with a third through hole 310, and the orthographic projection of the detection beam emitted by the electron gun 200 on the stage 100 overlaps with or is located within the orthographic projection of the third through hole 310 on the stage 100. The third through hole 310 is used to allow the detection beam to pass through the detector 300.

[0043] Optionally, the detection system further includes an electron gun 200, a deflector 500, an objective lens 600 and a booster 700. The electron gun 200 is located on the side of the detector 300 away from the filter plate 400. When the electron gun 200 is started, it emits a detection beam toward the stage 100. The deflector 500, the objective lens 600 and the booster 700 are all located between the filter plate 400 and the stage 100. The function of the objective lens 600 is to focus the detection beam onto the sample 11 on the stage 100. The deflector 500 is used to apply a lateral voltage to the detection beam, so that the detection beam undergoes a certain lateral deviation, and controls the detection beam to scan on the surface of the sample 11. The booster 700 applies a deceleration field to the detection beam to change the energy of the detection beam.

[0044] Optionally, the detection beam is focused multiple times before being irradiated on the sample 11, and the path of the detection beam can be regarded as approximately cylindrical. The path of the signal electron diverges in a cone shape.

[0045] The detection system 10 of the embodiment of the present application, by setting a filter plate 400 between the stage 100 and the detector 300, at least one first through hole 410 is set on the filter plate 400, and the first through hole 410 and the detector 300 are at least partially overlapped. A part of the signal electrons emitted by the sample is blocked by the filter plate 400, and the other part passes through the first through hole 410 and is collected by the detector 300, so that the current collected by the detector 300 becomes smaller, thereby increasing the saturation current threshold of the detector 300 in disguise, so that the electron gun 200 can emit a stronger detection beam to the sample 11 on the stage 100, thereby improving the detection effect of the detection system 10 on the sample.

[0046] In some optional embodiments, the filter plate 400 is further provided with a second through hole that penetrates the filter plate 400 along the first direction x, and the orthographic projection of the detection beam emitted by the electron gun 200 on the stage 100 overlaps with the orthographic projection of the second through hole 420 on the stage 100 or is located within the orthographic projection of the second through hole 420 on the stage 100.

[0047] Optionally, the diameter of the detection beam is less than or equal to 0.5 mm. When the second through hole 420 is circular, the diameter of the second through hole 420 is greater than or equal to 0.5 mm and less than or equal to 2.5 mm. When the second through hole 420 is square, the side length of the second through hole 420 is greater than or equal to 0.5 mm and less than or equal to 2.5 mm.

[0048] Optionally, the third through hole 310 is circular in shape, and the diameter of the third through hole 310 is greater than or equal to 0.5 mm.

[0049] The detection system 10 of the embodiment of the present application makes the orthographic projection of the detection beam overlap with the orthographic projection of the third through hole 310, or be located within the orthographic projection of the third through hole 310, so that the third through hole 310 will not block the detection beam at all, and the detection beam can be completely irradiated on the sample 11, thereby reducing the influence of the filter plate 400 on the detection beam.

[0050] Please refer to Figures 1 to 6 , Figure 3 A second schematic diagram showing a top view of an exemplary filter plate; Figure 4 A third schematic diagram showing a top view of an exemplary filter plate; Figure 5 A fourth schematic diagram showing a top view of an exemplary filter plate; Figure 6 A fifth schematic diagram of the top view structure of an exemplary filter plate is shown.

[0051] In some optional embodiments, a plurality of first through holes 410 are arranged around the second through hole 420 .

[0052] It is easy to understand that when the number of first through holes 410 increases, the number of signal electrons irradiated on the detector 300 through the first through holes 410 will also increase, and the current collected by the detector 300 will increase, but the detector 300 is more likely to reach the saturation current threshold. When the number of first through holes 410 decreases, the number of signal electrons blocked by the filter plate 400 increases, and the number of signal electrons irradiated on the detector 300 through the first through holes 410 decreases accordingly, and the current collected by the detector 300 decreases. The detector 300 is not easy to reach the saturation current threshold, but the detector 300 may miss the detection of sample 11 due to the omission of some signal electrons.

[0053] Optionally, the orthographic projections of the first through holes 410 on the stage 100 are all located within the orthographic projections of the detector 300 on the stage 100 .

[0054] Optional, such as Figure 3 As shown, a plurality of first through holes 410 are arranged in rows and columns.

[0055] Optionally, in the radial direction of the filter plate 400 and in the direction away from the second through holes 420, the spacing between adjacent first through holes 410 gradually increases (eg, Figure 4 and / or, in the radial direction of the filter plate 400 and in the direction away from the second through hole 420, the radial size of the first through hole 410 gradually increases (as shown in FIG. Figure 5and / or, in the radial direction of the filter plate 400, the filter plate 400 includes a first region 450 and a second region 460, the first region 450 is arranged around the second through hole 420, the second region 460 is arranged around the first region 450, and the radial dimension of the first through hole 410 located in the second region 460 is greater than the radial dimension of the first through hole 410 located in the first region 450 (as shown in FIG. Figure 6 As shown). When the first through hole 410 is circular, the radial dimension is its diameter or radius, and when the first through hole 410 is square, the radial dimension is its width. Figures 4 to 6 The embodiments in the foregoing can be arbitrarily combined. For example, in the radial direction of the filter plate 400 and in the direction away from the second through holes 420, the radial size of the first through holes 410 can be gradually increased, and the distance between two adjacent first through holes 410 can also be gradually increased.

[0056] The detection system 10 of the embodiment of the present application makes the orthographic projections of the first through holes 410 on the stage 100 all located within the orthographic projections of the detector 300 on the stage 100, so that all signal electrons passing through the first through holes 410 can be collected by the detector 300. By gradually increasing the spacing between adjacent first through holes 410 in the radial direction of the filter plate 400 and in the direction away from the second through holes 420, the detector 300 can collect more signal electrons at the middle position with lower collection efficiency, and collect fewer signal electrons at the edge position with higher collection efficiency, so that the difference in collection efficiency in the entire range of the detector 300 is small, and the collection efficiency is smoother.

[0057] In some optional embodiments, the shape of the second through hole 420 includes at least one of a circle, an ellipse, and a polygon, and the shape of the first through hole 410 includes at least one of a circle, an ellipse, a polygon, and a fan ring.

[0058] Optional, such as Figure 3 As shown, the shape of the first through holes 410 is a square, the side length of the first through holes 410 is greater than or equal to 0.2 mm and less than or equal to 1.2 mm, and the spacing between adjacent first through holes 410 is greater than or equal to 0.1 mm and less than or equal to 0.7 mm.

[0059] The collection efficiency of the detector 300 is affected by the size of the first through holes 410, the spacing between adjacent first through holes 410, and the voltage gain of the deflector 500. Therefore, this embodiment provides a plurality of different sizes of Figure 3 The filter plate 400 in the embodiment is tested, and the test structure is shown in Table 1. It should be noted that, in the present embodiment, the spacing between the second through hole 420 and the adjacent first through hole 410 is equal to the spacing between the two adjacent first through holes. Figure 3The dimension a in the figure refers to the side length of the first through hole 410. Figure 3 The distance between adjacent first through holes 410 of dimension b, Figure 3 The dimension c in φ refers to the side length of the second through hole 420 .

[0060]

[0061] Table 1

[0062] The ordinate in the table represents the collection efficiency of the detector 300, and the abscissa represents the voltage gain of the deflector 500, and its value is proportional to the voltage of the deflector 500. The ordinate represents the collection efficiency of the detector 300. Sample A0 in the table is a control group, which refers to the detection system 10 without the filter plate 400. It can be seen from the table that when the filter plate 400 is not set, when the voltage gain Gain of the deflector 500 is greater than 0.6, the collection efficiency of the detector 300 reaches 100%. Sample A1 in the table represents that the side length of the first through hole 410 is 0.4 mm, the spacing between adjacent first through holes 410 is 0.7 mm, and the side length of the second through hole 420 is 1.5 mm. Sample A2 in the table represents that the side length of the first through hole 410 is 0.4 mm, the spacing between adjacent first through holes 410 is 0.3 mm, and the side length of the second through hole 420 is 1.3 mm. Sample A3 in the table represents that the side length of the first through hole 410 is 0.2 mm, the spacing between adjacent first through holes 410 is 0.1 mm, and the side length of the second through hole 420 is 1.7 mm. Sample A4 in the table represents that the side length of the first through hole 410 is 0.65 mm, the spacing between adjacent first through holes 410 is 0.2 mm, and the side length of the second through hole 420 is 1.5 mm. Sample A5 in the table represents that the side length of the first through hole 410 is 0.7 mm, the spacing between adjacent first through holes 410 is 0.1 mm, and the side length of the second through hole 420 is 1.5 mm. Sample A6 in the table represents that the side length of the first through hole 410 is 1.2 mm, the spacing between adjacent first through holes 410 is 0.1 mm, and the side length of the second through hole 420 is 2.5 mm.

[0063] According to the data in Table 1, the collection efficiency of the detector 300 for signal electrons is negatively correlated with the spacing between adjacent first through holes 410. The larger the spacing between adjacent first through holes 410, the lower the collection efficiency of the detector 300 for signal electrons. The collection efficiency of the detector 300 for signal electrons is positively correlated with the side length of the first through hole 410 and the side length of the second through hole 420, and the side length of the first through hole 410 has a greater impact on the collection efficiency of the detector 300. The larger the side length of the first through hole 410, the higher the collection efficiency of the detector 300 for signal electrons.

[0064] Please refer to Figure 7 , Figure 7 A sixth schematic diagram of the top view structure of an exemplary filter plate is shown.

[0065] like Figure 7 As shown, in some optional embodiments, the second through hole 420 is circular in shape, and the first through hole 410 is in the shape of a sector ring surrounding the second through hole 420. The central angle of the sector ring of the first through hole 410 is greater than or equal to 5° and less than or equal to 9°.

[0066] A connecting rib 430 is formed between adjacent first through holes 410, and the connecting rib 430 is also in the shape of a fan ring. A fan ring refers to a part of a circular ring cut into a fan shape.

[0067] Optionally, the filter plate 400 is further provided with a reinforcing rib 440 connecting the plurality of connecting ribs 430 , and the reinforcing rib 440 is in a circular ring shape.

[0068] This embodiment provides a plurality of different sizes Figure 5 The filter plate 400 in the embodiment is tested, and the test structure is shown in Table 2 below. It should be noted that, in this embodiment, Figure 5 The dimension d in refers to the central angle of the first through hole 410. In this embodiment, the sum of the central angles of the first through hole 410 and the connecting rib 430 is 10°.

[0069]

[0070] Table 2

[0071] Sample B0 in the table is a control group, which refers to the detection system 10 without the filter plate 400. It can be seen from the table that when the filter plate 400 is not set, when the voltage gain Gain of the deflector 500 is greater than 0.6, the collection efficiency of the detector 300 reaches 100%. Sample B1 in the table represents that the center angle of the first through hole 410 is 5°, and the center angle of the connecting rib 430 is 5°. Sample B2 in the table represents that the center angle of the first through hole 410 is 6°, and the center angle of the connecting rib 430 is 4°. Sample B3 in the table represents that the center angle of the first through hole 410 is 7°, and the center angle of the connecting rib 430 is 3°. Sample B4 in the table represents that the center angle of the first through hole 410 is 8°, and the center angle of the connecting rib 430 is 2°. Sample B5 in the table represents that the center angle of the first through hole 410 is 9°, and the center angle of the connecting rib 430 is 1°.

[0072] According to the data in Table 2, the collection efficiency of the detector 300 for signal electrons is negatively correlated with the central angle of the connecting rib 430. The larger the central angle of the connecting rib 430, the lower the collection efficiency of the detector 300 for signal electrons. The collection efficiency of the detector 300 for signal electrons is positively correlated with the central angle of the first through hole 410. The larger the central angle of the first through hole 410, the higher the collection efficiency of the detector 300 for signal electrons.

[0073] Please refer to Figure 8 , Figure 8 FIG7 is a schematic diagram showing a top view of an exemplary filter plate.

[0074] like Figure 8 As shown, in some optional embodiments, the second through hole 420 is circular in shape, and the first through hole 410 is in the shape of a fan ring surrounding the second through hole 420. Connecting ribs 430 are formed between adjacent first through holes 410. A reinforcing rib 440 is also provided on the filter plate 400 to connect the plurality of connecting ribs 430, and the reinforcing rib 440 is in the shape of a circular ring. The plurality of reinforcing ribs 440 surround the second through hole 420 and are concentrically arranged.

[0075] This embodiment provides Figure 6 The filter plate 400 in the embodiment is tested, and the test structure is shown in Table 3 below. It should be noted that, in this embodiment, Figure 6 The dimension e in refers to the width of the first through hole 410 in the radial direction, the dimension f refers to the width of the reinforcing rib 440 in the radial direction, and the dimension g refers to the width of the connecting rib 430 in the circumferential direction.

[0076]

[0077] Table 3

[0078] Sample C0 in the table is a control group, which refers to the detection system 10 without the filter plate 400. It can be seen from the table that when the filter plate 400 is not provided, when the voltage gain Gain of the deflector 500 is greater than 0.6, the collection efficiency of the detector 300 reaches 100%. Sample C1 in the table represents that the radial width of the first through hole 410, the radial width of the reinforcing rib 440, and the circumferential width of the connecting rib 430 are all 0.1 mm.

[0079] It can be seen from Tables 1 to 3 that, compared with the rectangular first through hole 410 , the variation trend of the fan-shaped or annular first through hole 410 under different voltage gains of the deflector 500 is smoother.

[0080] In summary, the detection system 10 provided by the present application, by arranging the filter plate 400 between the stage 100 and the detector 300, the second through hole 420 is arranged on the filter plate 400, and the second through hole 420 and the electron gun 200 are at least partially overlapped, the detection beam emitted by the electron gun 200 can be irradiated on the sample 11 on the stage 100 through the second through hole 420, so that the filter plate 400 does not affect the detection beam. By arranging the first through hole 410 on the filter plate 400, and making the first through hole 410 and the detector 300 at least partially overlap, a part of the signal electrons emitted by the sample are blocked by the filter plate 400, and the other part passes through the first through hole 410 and is collected by the detector 300, so that the current collected by the detector 300 becomes smaller, and the saturation current threshold of the detector 300 is increased in disguise, so that the electron gun 200 can emit a stronger detection beam, and the detection effect of the detection system 10 on the sample is improved.

[0081] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A detection system (10), characterized in that: include: A stage (100) for carrying a sample (11); a detector (300) arranged at a distance from the stage (100) along a first direction, the detector (300) being used to collect signal electrons emitted by the sample (11); A filter plate (400) is located between the stage (100) and the detector (300), and at least one first through hole (410) is provided on the filter plate (400) and passes through the filter plate (400) along the first direction, and an orthographic projection of the first through hole (410) on the stage (100) at least partially overlaps with an orthographic projection of the detector (300) on the stage (100).

2. The detection system (10) according to claim 1, characterized in that: It also includes an electron gun (200), the electron gun (200) being located on a side of the detector (300) away from the filter plate (400), and the electron gun (200) generating a detection beam toward the stage (100) when started; The filter plate (400) is also provided with a second through hole (420) penetrating the filter plate (400) along the first direction, and the orthographic projection of the detection beam emitted by the electron gun (200) on the stage (100) overlaps with the orthographic projection of the second through hole (420) on the stage (100) or is located within the orthographic projection of the second through hole (420) on the stage (100).

3. The detection system (10) according to claim 2, characterized in that: The diameter of the detection beam is less than or equal to 0.5 mm; When the shape of the second through hole (420) is circular, the diameter of the second through hole (420) is greater than or equal to 0.5 mm and less than or equal to 2.5 mm; when the shape of the second through hole (420) is square, the side length of the second through hole (420) is greater than or equal to 0.5 mm and less than or equal to 2.5 mm.

4. The detection system (10) according to claim 2, characterized in that: A plurality of the first through holes (410) are arranged around the second through hole (420).

5. The detection system (10) according to claim 4, characterized in that: The orthographic projections of the first through holes (410) on the stage (100) are all located within the orthographic projections of the detector (300) on the stage (100).

6. The detection system (10) according to claim 4, characterized in that: In the radial direction of the filter plate (400) and in the direction away from the second through hole (420), the spacing between adjacent first through holes (410) gradually increases; and / or, in the radial direction of the filter plate (400) and in the direction away from the second through hole (420), the radial dimension of the first through hole (410) gradually increases; And / or, in the radial direction of the filter plate (400), the filter plate (400) includes a first area (450) and a second area (460), the first area (450) is arranged around the second through hole (420), the second area (460) is arranged around the first area, and the radial size of the first through hole (410) located in the second area (460) is larger than the radial size of the first through hole (410) located in the first area (450).

7. The detection system (10) according to claim 4, characterized in that: A plurality of the first through holes (410) are arranged in rows and columns.

8. The detection system (10) according to claim 2, characterized in that: The shape of the second through hole (420) includes at least one of a circle, an ellipse, and a polygon, and the shape of the first through hole (410) includes at least one of a circle, an ellipse, a polygon, and a fan ring.

9. The detection system (10) according to claim 8, characterized in that: The first through holes (410) are all in the shape of a square, and the side length of the first through holes (410) is greater than or equal to 0.2 mm and less than or equal to 1.2 mm; the spacing between adjacent first through holes (410) is greater than or equal to 0.1 mm and less than or equal to 0.7 mm.

10. The detection system (10) according to claim 8, characterized in that The second through hole (420) is circular in shape, and the first through hole (410) is in the shape of a fan ring surrounding the second through hole (420); the central angle of the fan ring of the first through hole (410) is greater than or equal to 5° and less than or equal to 9°.

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