A sample stage for scanning electron microscope and its usage method

Abstract

This application relates to a scanning electron microscope (SEM) sample stage and its usage method, belonging to the field of geological sample testing technology, and aims to solve the problem that existing sample stages are difficult to adapt to sample targets of different sizes. The SEM sample stage includes a base and a clamping structure disposed on the base; the clamping structure has a clamping space and a stage disposed within the clamping space; wherein the axis of the clamping space coincides with the axis of the sample target mounted on the stage, and the size of the clamping space is adjustable to accommodate sample targets of different sizes; the top opening of the clamping space allows the sample target to be installed to be placed on the stage facing forward through the top opening of the clamping space. This application achieves the clamping and fixing of sample targets of different sizes.

Description

Technical Field

[0001] This application belongs to the field of geological sample testing technology, and specifically relates to a scanning electron microscope sample stage and its usage method. Background Technology

[0002] In geological science experiments and automated mineralogical analysis, current sample stages have shortcomings in terms of installation, operation, and size adaptation. The internal cylindrical cavity of existing sample stages has a fixed size, making it unsuitable for cylindrical epoxy resin sample targets of different sizes. When the sample size exceeds or falls below the cavity specifications, it cannot be placed properly, significantly limiting its application. Furthermore, when installing the epoxy resin sample target, the top cover must be removed, and the target placed face down on the table with the top surface (test surface) facing down inside the cavity. This not only easily leads to confusion but also easily scratches the top test surface of the epoxy resin sample target, adversely affecting subsequent analysis and testing. Summary of the Invention

[0003] In view of the above analysis, the present invention aims to provide a scanning electron microscope sample stage and its usage method to solve the problem that the sample stage in the prior art is difficult to adapt to epoxy resin sample targets of different sizes.

[0004] The objective of this invention is achieved as follows:

[0005] On one hand, a sample stage for a scanning electron microscope is provided, including a base and a clamping structure disposed on the base; the clamping structure has a clamping space and a stage disposed inside the clamping space; wherein, the axis of the clamping space coincides with the axis of the sample target mounted on the stage, and the size of the clamping space is adjustable to accommodate sample targets of different sizes; the top opening of the clamping space is provided so that the sample target to be installed can be placed on the stage from the top opening of the clamping space.

[0006] Furthermore, the size of each of the multiple clamping spaces can be adjusted independently.

[0007] Furthermore, the clamping structure has multiple clamping contact positions with the cylindrical side surface of the sample target. These multiple clamping contact positions are symmetrically arranged with respect to the axis of the sample target and are located on the same cylindrical surface.

[0008] Furthermore, the clamping structure also has a drive mechanism and a clamping assembly, which are disposed on the base. The clamping assembly forms a clamping space, and the drive mechanism is connected to the clamping assembly and configured to adjust the size of the clamping space.

[0009] Furthermore, the clamping assembly has four vertically parallel clamping rods located on the same circumference, forming a clamping space above the base; the base has a cross-shaped sliding groove with four directional slots, and the lower ends of the four clamping rods are slidably disposed in the four slots respectively; the driving mechanism is located at the bottom of the base and is drivenly connected to the four clamping rods, used to drive the four clamping rods to synchronously approach or move away from the axis of the clamping space in their respective slots.

[0010] Furthermore, the clamping structure also has a knob, which is set on the base and coupled to the drive mechanism. The knob and the drive mechanism control the four clamping rods to move closer to or further away from the center of the cross groove to clamp or release the sample target on the stage.

[0011] Furthermore, the drive mechanism includes a base, a first shaft, a winch, a stranded wire, an end face gear, a bevel gear, a second shaft, and a locking assembly. The base is connected to the base and is located in the middle of the cross groove. The first shaft is connected to the base. The winch includes two winches, which are rotatably connected to the outer end of the first shaft. The two winches are fixedly connected to the end face gear, which is located on the outermost side. The second shaft passes through the base and is rotatable. One end is connected to a knob, and the other end is connected to the bevel gear. The bevel gear meshes with the end face gear. The locking assembly is located on the second shaft and is used to lock and unlock the rotation of the second shaft. The stranded wire includes two strands. One stranded wire is connected to two opposing clamping rods arranged longitudinally in the cross groove and passes through the side wall of the inner winch. The other stranded wire is connected to two opposing clamping rods arranged transversely in the cross groove and passes through the side wall of the middle winch.

[0012] Furthermore, the side wall of the winch is provided with a wire groove, and the winch is provided with a wire hole. The wire hole is located in the middle of the wire groove, and the wire hole forms two opposite openings in the wire groove. The stranded wire passes through the wire hole, and the stranded wire is connected to the bottom end of the clamping rod.

[0013] Furthermore, the locking assembly includes a locking nut, a locking washer, and a limiting plate. The limiting plate is connected to the bottom surface of the base near the inner wall of the base, and the second shaft passes through the limiting plate. The locking washer is disposed between the limiting plate and the inner wall of the base, and is in close contact with the limiting plate and the base. The locking washer is sleeved on the second shaft. The locking nut is disposed between the knob and the outer wall of the base. The second shaft has threads between the knob and the locking washer, and the locking nut is threadedly connected to the second shaft.

[0014] Furthermore, the clamping structure also includes slide rails, which are respectively set on both sides of each slot section. The side wall of the slide rail is provided with a sliding opening, and the side wall of the clamping rod is provided with two symmetrical sliding plates. The sliding plates are slidably connected to the sliding opening of an adjacent slide rail.

[0015] Furthermore, it also includes a leveling mechanism and a levelness detection mechanism. The levelness detection mechanism is used to detect the levelness of the top surface of the sample target on the stage, and the leveling mechanism is used to adjust the levelness of the top surface of the sample target.

[0016] Furthermore, the levelness detection mechanism includes a pressure plate, a pressure sensor, an elastic connector, and a pressure head. The pressure sensor is connected to the side of the pressure plate facing the stage. The pressure sensor includes multiple sensors arranged in a circular array. One end of the elastic connector is connected to the detection end of the pressure sensor, and the pressure head is connected to the other end of the elastic connector. The elastic connector generates pressure on the sample target through the pressure head.

[0017] Furthermore, the shelf includes an elastic element and a shelf plate, the shelf plate being connected to the elastic element, the elastic element being connected to the base and located in the middle of the cross groove;

[0018] Furthermore, the leveling mechanism includes an adjusting screw, a top rod, and a top ring. The top of the clamping rod has a insertion hole, and the adjusting screw is rotatably connected to the top of the insertion hole. The side wall of the clamping rod facing the center of the cross groove has a top groove, which communicates with the insertion hole. The adjusting screw is threadedly connected to the top ring, which is located inside the insertion hole. The side wall of the top ring is connected to the top rod, and the top rod is slidably connected to the top groove. The top rod extends into the clamping space and is located below the shelf.

[0019] On the other hand, a method for using a sample stage for a scanning electron microscope is also provided, including:

[0020] Step S1: Adjust the size of the clamping space of the clamping structure according to the size of the sample target, so that the size of the clamping space is larger than the diameter of the sample target;

[0021] Step S2: Place the sample target onto the stage from the top opening of the clamping space;

[0022] Step S3: readjust the size of the clamping space of the clamping structure, gradually reduce the size of the clamping space until the clamping assembly clamps and fixes the sample target, and completes the installation of the sample target;

[0023] Step S4: After the test is completed, increase the size of the clamping space, and then directly remove the sample target to complete the sample target disassembly.

[0024] Furthermore, between steps S2 and S3, a sample target top surface leveling step S2A is also included:

[0025] After the sample target is placed on the stage, the levelness of the top surface of the sample target is detected by the levelness detection mechanism. Based on the detection results, the leveling mechanism is used to adjust the levelness of the top surface of the sample target until the top surface of the sample target is leveled.

[0026] Compared with the prior art, the scanning electron microscope sample stage and its usage method provided by the present invention can achieve at least one of the following beneficial effects:

[0027] 1. The clamping structure adopts an adjustable clamping space. By adjusting the size of the clamping space, it can clamp and fix sample targets of different sizes, which solves the problem that the installation cavity size of traditional sample stages cannot be adjusted. It can be adapted to sample targets of different sizes.

[0028] 2. The top opening of the clamping space allows the sample target to be placed on the stage facing forward through the top opening of the clamping space. Unlike traditional sample stages, the top cover does not need to be removed during sample loading, and the sample target will not be confused due to the top cover being flipped up. This structure not only makes the sample loading operation more convenient and prevents the sample target from being confused due to the top cover being flipped up, but also minimizes the adverse effects such as wear or scratches on the top surface of the sample target during the sample loading process.

[0029] 3. The clamping space of the clamping structure is adjustable, controlled by rotating a knob. Rotating the knob controls the drive mechanism to move the clamping rods towards the end of their respective slots, increasing the clamping space. When the sample target is placed on the stage, rotating the knob again controls the drive mechanism to move the clamping rods towards the center intersection of the cross-shaped grooves, decreasing the clamping space. Simultaneously, the clamping rods abut against the sample target, securing it in place. Using a knob, clamping rods, and drive mechanism to adjust the clamping space is not only simple to operate but also allows for continuous adjustment to accommodate sample targets of different sizes. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of this specification. For those skilled in the art, other drawings can be obtained based on these drawings.

[0031] Figure 1 This is a schematic diagram of the overall structure of a scanning electron microscope sample stage provided in Embodiment 1 of the present invention;

[0032] Figure 2 for Figure 1 A magnified schematic diagram of a portion of region A in the middle;

[0033] Figure 3 This is a schematic diagram of the bottom structure of the base of a scanning electron microscope sample stage provided in Embodiment 1 of the present invention;

[0034] Figure 4 for Figure 3 A partial structural diagram of the bottom of the central base;

[0035] Figure 5 for Figure 3 A magnified schematic diagram of a portion of region B in the middle;

[0036] Figure 6 for Figure 3 A magnified schematic diagram of a portion of region D in the middle;

[0037] Figure 7 This is a partial structural schematic diagram of a scanning electron microscope sample stage provided in Embodiment 2 of the present invention;

[0038] Figure 8 This is a schematic diagram of the structure of a scanning electron microscope sample stage provided in Embodiment 2 of the present invention (only one clamping structure is shown);

[0039] Figure 9 for Figure 8 A magnified schematic diagram of the structure of region C in the middle.

[0040] Figure label:

[0041] 10. Base; 11. Cross groove; 12. Clamping rod; 13. Stage; 131. Elastic element; 132. Placement plate; 14. Sample target; 15. External support;

[0042] 20. Drive mechanism; 201. Base; 202. First shaft; 203. Winch; 2031. Wire groove; 2032. Wire hole; 204. Stranded wire; 205. End face gear; 206. Bevel gear; 207. Second shaft; 208. Locking nut; 209. Locking washer; 210. Limiting plate;

[0043] 30. Knob; 30A. Central area control knob;

[0044] 40. Slide rail; 41. Skateboard;

[0045] 50. Pressure plate; 51. Pressure sensor; 52. Elastic connector; 53. Pressure head;

[0046] 60. Adjusting screw; 61. Push rod;

[0047] 70. Column; 71. Elastic band. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. It should be noted that, unless otherwise specified, the implementation methods and features in the implementation methods in this disclosure can be combined, separated, interchanged, and / or rearranged. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] In the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.

[0050] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “(the)” are also intended to include the plural forms. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0051] Example 1

[0052] In one specific embodiment of the present invention, a sample stage for a scanning electron microscope is disclosed for mounting a cylindrical epoxy resin sample target (hereinafter referred to as "sample target 14"). The sample stage for the scanning electron microscope can be adapted to sample targets 14 of different diameters.

[0053] like Figures 1 to 6As shown, a sample stage for a scanning electron microscope includes a base 10 and a clamping structure disposed on the base 10. The clamping structure has a clamping space and a stage 13 disposed inside the clamping space. The axis of the clamping space coincides with the axis of the sample target 14 mounted on the stage 13, and the size of the clamping space is adjustable. The clamping space has multiple clamping sizes to accommodate sample targets 14 of different sizes. The top opening of the clamping space is provided so that the sample target 14 to be installed can be placed on the stage 13 from the top opening of the clamping space. After clamping and fixing, the top surface of the sample target 14 is higher than the top opening of the clamping space to ensure normal analysis and detection of the top surface of the sample target 14 by the instrument.

[0054] In this embodiment, the cylindrical epoxy resin sample target is suitable for a scanning electron microscope. The scanning electron microscope is equipped with automatic mineral analysis software. During automatic mineral analysis, the epoxy resin sample target is clamped and fixed in the clamping space of the clamping structure. Then, other instrument operation steps are performed to realize automatic mineral analysis of the sample target 14.

[0055] In this embodiment, the sample target 14 is ideally a regular cylindrical structure, meaning that the top and bottom surfaces of the sample target 14 are two parallel planes, with the top surface serving as the test surface. In this embodiment, "positive placement" means that the sample target 14 is installed with the test surface facing upwards, and the bottom surface of the sample target 14 is placed on the stage 13, where it can be bonded and fixed.

[0056] In this embodiment, the clamping structure and the cylindrical side surface of the sample target 14 have multiple clamping contact positions. The multiple clamping contact positions are arranged symmetrically with respect to the axis of the sample target 14, and the multiple clamping contact positions are located on the same cylindrical surface. It should be noted that in this embodiment, the clamping contact positions between the clamping space and the sample target 14 can be point contact, line contact, or surface contact.

[0057] In one alternative embodiment, the clamping structure further includes a drive mechanism 20 and a clamping assembly, which are disposed on the base 10. The clamping assembly forms a clamping space, and the drive mechanism 20 is connected to the clamping assembly and configured to adjust the size of the clamping space.

[0058] Furthermore, a rubber layer is provided at the contact position between the clamping space and the side peripheral surface of the sample target 14. The rubber layer is provided on the clamping assembly. This structure allows the side peripheral surface of the sample target 14 to be flexibly clamped with the clamping assembly, which can increase the friction between the clamping assembly and the side peripheral surface of the sample target 14.

[0059] For example, the clamping assembly has four vertically parallel clamping rods 12 located on the same circumference; a cross groove 11 is formed on the base 10, each cross groove 11 having four segments connected in the four directions (up, down, left, and right) at its center point; the four clamping rods 12 are respectively disposed in the four segments of the cross groove 11 and slidably connected to the segments; the clamping rods 12 also extend to the bottom of the base 10, and the four clamping rods 12 form a clamping space above the base 10. In this configuration, the four clamping contact positions formed by the four clamping rods 12 and the side circumferential surface of the sample target 14 are line contacts; the driving mechanism 20 is disposed at the bottom of the base 10 and is drivenly connected to the clamping rods 12, used to drive the clamping rods 12 to move synchronously towards or away from the axis of the clamping space in their respective segments. This structural configuration allows the clamping space to have multiple continuously adjustable clamping dimensions.

[0060] In this embodiment, the stage 13 is disposed on the base 10 and is located in the middle of the cross groove 11 to support the sample target 14. The axis of the stage 13 coincides with the axis of the clamping space.

[0061] In this embodiment, the drive mechanism 20 can be driven by a motor or manually, so as to adjust the size of the clamping space.

[0062] In one alternative embodiment, the drive mechanism 20 is manually operated. Specifically, the clamping structure also includes a knob 30, which is mounted on the base 10 and coupled to the drive mechanism 20. The knob 30 controls the four clamping rods 12 to move closer to or further away from the center of the cross groove 11 to clamp or release the sample target 14 on the stage 13. Optionally, the knob 30 can be connected to the drive structure 20 via a connecting shaft and gears. During sample loading, rotating the knob controls the drive mechanism 20 to move the clamping rods 12 towards the end of their respective slots, increasing the clamping space. The sample target 14 is then placed face-up on the stage 13 from the top opening of the clamping space. Rotating the knob again in the opposite direction controls the drive mechanism 20 to move the clamping rods 12 towards the middle intersection of the cross grooves 11 within the slots, reducing the clamping space until all four clamping rods 12 simultaneously abut against the side surface of the sample target 14, thus fixing the sample target 14. In this embodiment, to ensure normal detection of the top surface of the sample target 14 by the instrument, the top of the clamping rod 12 is lower than the top surface of the sample target 14. Optionally, after the sample target 14 is placed on the stage 13 and clamped and fixed by the clamping space, the top of the clamping rod 12 is located at the middle of the side surface of the sample target 14.

[0063] In this embodiment, multiple clamping structures are arranged in an N×M row and column configuration on the base 10, where N is the number of rows of the clamping structures and M is the number of columns of the clamping structures, and both N and M are integers greater than 1. For example, the clamping structures on the base 10 can be arranged in 3×3, 4×4, 3×4, 3×5, 4×5, etc., to meet the usage requirements of multiple sample targets, such as 9, 12, 16, 15, 20, etc.

[0064] It should be noted that the knob 30 can be located on the side of the base 10, such as... Figure 1 , Figure 3 As shown; the knob 30 can also be located on the top surface of the base 10 and in the area next to the cross groove 11 (not shown in the figure); of course, some knobs can also be located on the side of the base 10 and some knobs 30 can be located on the top surface of the base 10; different knobs 30 (and their connected parts) do not interfere with each other, ensuring independent drive control of each clamping structure, so that a sample stage can simultaneously perform detection of sample targets of different sizes. For example, Figure 1 Nine clamping structures are provided on the base 10, eight of which are located at the four edges of the base 10. The knobs 30 corresponding to these eight clamping structures are located on the side of the base 10. The knob corresponding to the clamping structure located in the middle is called the middle area knob 30A. The middle area control knob 30A can also be arranged on the side of the base 10 without interfering with the adjacent knobs 30 and their connecting parts.

[0065] In this embodiment, the base 10 serves as an integral support structure. A cross-shaped groove 11 is formed on the base 10, comprising four vertically intersecting grooves in both the longitudinal and transverse directions. The cross-shaped groove 11 provides a sliding path for the four clamping rods 12. A clamping rod 12 is installed on each of the upper longitudinal groove, the lower longitudinal groove, the left transverse groove, and the right transverse groove. The clamping rods 12 pass through the cross-shaped groove 11 and extend to the bottom of the base 10, connecting to the drive mechanism 20. The four clamping rods 12 enclose an adjustable clamping space above the base 10. A platform 13 is located at the center of the cross-shaped groove 11 to support the sample target 14. When the knob 30 is rotated, the knob 30, through the coupled drive mechanism 20, drives the four clamping rods 12 to move synchronously along their respective grooves: when moving towards the ends of the groove, the clamping space expands; when moving towards the center of the cross intersection, the clamping space shrinks, until the sides of the clamping rods 12 contact and clamp the side surface of the sample target 14, thus fixing the sample target 14.

[0066] This embodiment uses a clamping structure with knob 30, which eliminates the need to remove the top cover. The sample target 14 is placed directly on the stage 13, and the clamping / release of the sample target 14 is completed by turning knob 30 with one hand. The operation steps are reduced from 5 steps of traditional sample stage loading to 3 steps, and the position of the sample target 14 is swapped due to the top cover being reversed, which reduces the risk of confusion when detecting multiple sample targets 14.

[0067] In some alternative embodiments, the drive mechanism 20 includes a base 201, a first shaft 202, a winch 203, a stranded wire 204, an end-face gear 205, a bevel gear 206, a second shaft 207, and a locking assembly. The base 201 is connected to the base 10 and is located in the middle of the cross groove 11. The first shaft 202 is connected to the base 201. Two winches 203 are included, and the two winches 203 and the end-face gear 205 are rotatably connected to the outer end of the first shaft 202. The two winches 203 are fixedly connected to the end-face gear 205, with the end-face gear 205 located on the outermost side. The second shaft 207 passes through... The base 10 is rotatable, with one end connected to the knob 30 and the other end connected to the bevel gear 206. The bevel gear 206 meshes with the end face gear 205. A locking assembly is provided on the second shaft 207 for locking and unlocking the rotation of the second shaft 207. Two stranded wires 204 are included. One stranded wire 204 is connected to two opposing clamping rods 12 arranged longitudinally in the cross groove 11 and passes through the side wall of the inner winch 203. The other stranded wire 204 is connected to two opposing clamping rods 12 arranged laterally in the cross groove 11 and passes through the side wall of the winch 203 located in the middle.

[0068] When the knob 30 is rotated, the second shaft 207 drives the bevel gear 206 to rotate. The bevel gear 206 drives the end face gear 205 and the two winches 203 to rotate synchronously. The rotation of the winches 203 will wind up the stranded wire 204. When winding up the wire, the four clamping rods 12 move synchronously toward the central axis of the clamping space until they abut against the side circumferential surface of the sample target 14. The second shaft 207 is locked by the locking assembly, and the clamping rods 12 remain fixed to the sample target 14. When releasing the wire, the knob 30 is turned in the opposite direction, and the four clamping rods 12 are pulled toward their respective slot ends. The winches 203 rotate in the opposite direction, and the four clamping rods 12 reset synchronously. The stranded wire 204 resets and returns to a straight state.

[0069] The meshing of the bevel gear 206 and the end face gear 205, along with the symmetrical winding and unwinding of the stranded wire 204, ensures that the four clamping rods 12 move synchronously in the longitudinal and transverse directions, and that the clamping force is evenly distributed, thus preventing the sample target 14 from tilting or deforming due to unilateral force.

[0070] In this embodiment, the stranded wire 204 is made of high-strength nylon material (tensile strength ≥50MPa), and with the directional winding and unwinding of the winch 203, it can provide a stable clamping force to meet the fixation requirements of the sample target 14.

[0071] The drive mechanism 20 is integrated into the bottom of the base 10, without occupying the space above the sample target 14, and is suitable for the narrow chamber environment of equipment such as scanning electron microscopes.

[0072] The winch 203 has a wire groove 2031 on its side wall and a wire hole 2032 on its side wall. The wire hole 2032 is located in the middle of the wire groove 2031 and forms two opposite openings in the wire groove 2031. The stranded wire 204 passes through the wire hole 2032 and is connected to the bottom end of the clamping rod 12.

[0073] The winch 203 has an annular groove 2031 on its side wall, with a wire hole 2032 through the center of the groove 2031. The diameter of the wire hole 2032 is slightly larger than the diameter of the stranded wire 204. The groove 2031 is annular, which guides the stranded wire 204 to wind or unwind orderly along the groove 2031 when the winch 203 rotates, preventing tangling. The wire hole 2032 is located in the center of the groove 2031 and passes through the winch 203. After the stranded wire 204 passes through the wire hole 2032, its two ends are connected to two opposing clamping rods 12. When the winch 203 rotates clockwise, the stranded wire 204 is wound in the groove 2031, pulling the two clamping rods 12 towards the center; when it rotates counterclockwise, the stranded wire 204 is released, and the clamping rods 12 move towards both ends under the action of a restoring force. The position of the wire hole 2032 ensures that the stranded wire 204 is always in the center of the wire groove 2031, avoiding uneven force caused by bias to one side.

[0074] In some optional embodiments, the clamping structure is further provided with an automatic reset mechanism located at the bottom of the base 10, for automatically resetting the clamping rods 12, enabling the clamping rods 12 to move towards the end of the groove segment. Specifically, the automatic reset mechanism includes four columns 70 and an elastic band 71. The four columns 70 are arranged in a rectangle, with each column 70 located at one of the four corners of the rectangle. The rectangle formed by the four columns 70 is centered on the base 201, and each column 70 is located at the midpoint of two adjacent clamping rods 12. Furthermore, in the reset state, the four clamping rods 12 are exactly located on the four sides of the rectangle formed by the four columns 70, and each clamping rod 12 is located at the midpoint of its respective side. The elastic band 71 is first threaded through the side walls of the four uprights 70, and located on the outer side of the four uprights 70. At this time, the elastic band 71 also forms a rectangular structure, with each side of the elastic band 71 corresponding to one upright 70, and the clamping rod 12 on the corresponding side is also located at the midpoint of the corresponding side of the elastic band 71. One side of the elastic band 71 passes through the outer side wall of the clamping rod 12, and the elastic band 71 is located on the inner side of the clamping rod 12. After the elastic band 71 is threaded through the clamping rod 12 and the uprights 70, it remains taut.

[0075] When the clamping rod 12 moves toward the center of the cross groove 11, that is, toward the base 201, the clamping rod 12 pulls the elastic band 71, giving the elastic band 71 an outward pulling force. Therefore, when the clamping rod 12 is in the non-reset position of its respective groove segment, the outward pulling force of the elastic band 71 will pull the clamping rod 12 toward the groove end, causing the clamping rod 12 to automatically reset.

[0076] In some alternative embodiments, the locking assembly includes a locking nut 208, a locking washer 209, and a limiting plate 210. The limiting plate 210 is connected to the bottom surface of the base 10 near the inner wall of the base 10, and the second shaft 207 passes through the limiting plate 210. The locking washer 209 is disposed between the limiting plate 210 and the inner wall of the base 10, and is in close contact with the limiting plate 210 and the base 10. The locking washer 209 is sleeved on the second shaft 207. The locking nut 208 is disposed between the knob 30 and the outer wall of the base 10. The second shaft 207 has threads between the knob 30 and the locking washer 209, and the locking nut 208 is threadedly connected to the second shaft 207.

[0077] The locking assembly consists of a locking nut 208, a locking washer 209, and a limiting plate 210. The limiting plate 210 is fixed to the bottom surface of the base 10 near the inner wall. The second shaft 207 passes through the limiting plate 210 and is rotatable. The locking washer 209, made of metal or nylon, is fitted onto the second shaft 207 and clamped between the limiting plate 210 and the inner wall of the base 10. The locking nut 208 is threaded to one side of the knob 30 on the second shaft 207 (located between the knob 30 and the outer wall of the base 10). After the sample target 14 is clamped and fixed, the locking nut 208 is tightened clockwise. The nut presses against the outer wall of the base 10, locking the second shaft 207 through friction and preventing its rotation. When adjustment is needed, the locking nut 208 is loosened counterclockwise, and the second shaft 207 regains its rotational freedom.

[0078] Once locked, the second shaft 207 effectively resists vibrations and accidental touches during the operation of the scanning electron microscope, ensuring the sample target 14 remains stable and secure during the detection process. No additional tools are required; locking / unlocking can be completed by hand-tightening the locking nut 208, adapting to the laboratory's rapid sample change requirements.

[0079] In some alternative embodiments, the clamping structure further includes slide rails 40, which are respectively disposed on both sides of each slot segment. The side wall of the slide rail 40 is provided with a sliding opening, and the side wall of the clamping rod 12 is provided with two symmetrical sliding plates 41. The sliding plates 41 are slidably connected to the sliding opening of one of the adjacent slide rails 40.

[0080] Each groove segment has parallel slide rails 40 on both sides, and rectangular sliding openings are formed on the opposite sidewalls of the slide rails 40. The clamping rod 12 has two symmetrical sliding plates 41 on its sidewall facing the slide rails 40. The sliding plates 41 are embedded in the sliding openings and can slide along them. When the clamping rod 12 moves, the sliding plates 41 slide within the sliding openings. The slide rails 40 and the sliding openings restrict the vertical and horizontal displacement of the sliding plates 41, allowing the clamping rod 12 to move linearly only along the length of the groove segment.

[0081] The cooperation between the slide rail 40 and the slide plate 41 ensures that the clamping rod 12 moves without wobbling, keeping the center of the sample target 14 always aligned with the center of the stage 13, thus guaranteeing the focusing accuracy of the scanning electron microscope's electron beam. The low-friction characteristics of the PTFE slide plate 41 and the stainless steel slide rail 40 reduce the resistance to movement of the clamping rod 12, and, in conjunction with the drive mechanism 20, enable smooth adjustment, preventing the sample target 14 from shifting due to sudden force. The self-lubricating properties of the slide plate 41 reduce wear over long-term use, extending its service life and reducing maintenance frequency.

[0082] This application also provides a method for using a sample stage for a scanning electron microscope, including the following steps:

[0083] Step S1: Adjust the size of the clamping space of the clamping structure according to the size of the sample target 14, so that the size of the clamping space is larger than the diameter of the sample target 14;

[0084] Step S2: Place the sample target 14 onto the stage 13 from the top opening of the clamping space;

[0085] Step S3: readjust the size of the clamping space of the clamping structure, gradually reduce the size of the clamping space until the size of the clamping space is equal to the outer peripheral surface of the sample target 14. The clamping components of the clamping structure are pressed into contact with the outer peripheral surface of the sample target 14. The clamping components apply a certain clamping force to the side peripheral surface of the sample target 14 to ensure that sufficient fixed clamping force is formed on the sample target 14, and the installation of the sample target 14 is completed.

[0086] Step S4: When the test is completed and the sample target 14 needs to be removed, simply increase the size of the clamping space again, and then remove the sample target 14 directly.

[0087] The specific steps are as follows:

[0088] The knob 30 on the side of the rotating base 10 drives the four clamping rods 12 to move synchronously along the corresponding groove ends of the cross slide groove 11 through the drive mechanism 20, so that the clamping space formed by the four clamping rods 12 above the base 10 increases until the size of the clamping space is larger than the size of the sample target 14 to be installed.

[0089] Place the sample target 14 on the stage 13 in the middle of the cross groove 11 on the base 10, ensuring that the bottom surface of the sample target 14 is in contact with the surface of the stage 13, and that the main body of the sample target 14 is located in the clamping space.

[0090] Rotate the knob 30 in the opposite direction, and drive the four clamping rods 12 to move synchronously along the cross center of the cross groove 11 through the drive mechanism 20, so that the clamping space gradually shrinks; until the inner sidewalls of the four clamping rods 12 contact the sidewalls of the sample target 14 respectively and apply a stable clamping force, the sample target 14 is firmly fixed, and the installation of the sample target 14 is completed.

[0091] Compared with the prior art, the scanning electron microscope sample stage and its usage method provided in this embodiment, by adjusting the size of the clamping space of the clamping structure and setting the top opening of the clamping space, eliminates the need to disassemble the top cover or other parts during the sample loading process. This eliminates the cumbersome steps of removing the top cover and flipping and placing the sample on the traditional sample stage. The sample target installation process is simplified from multiple steps to three steps: adjusting the space, placing the sample, and fixing the sample. This not only meets the needs of rapid sample change in the laboratory, but also allows for flexible adjustment of the size of the clamping space, which can accommodate sample targets of various sizes. This expands the applicability of the sample stage, reduces the cost of instrument accessories, and successfully solves the technical problem that the fixed size of the installation cavity of the traditional sample stage means that a sample stage can only install a single size sample target.

[0092] Example 2

[0093] In practical analysis and testing, it has been found that the prepared sample target 14 is sometimes not an ideal, regular cylindrical structure. In particular, the top or bottom surface of the sample target 14 is not horizontal. However, it is essential to ensure that the test surface of the top surface of the sample target 14 is horizontal in order to obtain accurate test results. Based on this, another specific embodiment of the present invention discloses a sample stage for scanning electron microscopes. The difference from Embodiment 1 is that it also includes a leveling mechanism and a levelness detection mechanism. The levelness detection mechanism is used to detect the levelness of the top surface of the sample target 14 on the stage 13, and the leveling mechanism is set on the clamping rod 12 to adjust the levelness of the top surface of the sample target 14.

[0094] Considering that the axis of the sample target 14 will tilt slightly during fine-tuning of the top surface level, resulting in a slight tilt of the side surface of the sample target, a rubber layer can be provided on the clamping rods 12 to ensure stable and effective clamping of the side surface of the sample target by the four clamping rods 12. The rubber layer is a hollow tubular structure and is sleeved on the clamping rods 12. Since the rubber layer has a certain thickness, such as 2-3 mm, it has a certain deformation capacity during clamping. Even if the top surface of the sample target 14 tilts slightly during leveling, it can ensure that the clamping positions of the four clamping rods 12 and the side surface of the sample target all have a line contact, thus ensuring the clamping stability of the sample target.

[0095] The levelness detection mechanism can detect the levelness deviation of the top surface of the sample target 14 through contact or non-contact methods to obtain the tilt data of the top surface of the sample target. Alternatively, existing levelness detection methods such as bubble offset can also be used to detect the tilt of the top surface of the sample target. Based on the tilt detection results, a leveling mechanism mounted on the four clamping rods 12 is used to finely adjust the height of different parts of the sample target 14 until the top surface of the sample target 14 is adjusted to a level state. For example, if the sample target 14 is tilted in one direction, the leveling mechanisms on both sides or directly corresponding to that direction are controlled to raise / lower the height of the sample target 14 in that direction, until the levelness detection mechanism reports that the top surface of the sample target 14 is level.

[0096] In one alternative implementation, see Figures 7 to 9 The levelness detection mechanism includes a pressure plate 50, a pressure sensor 51, an elastic connector 52, and a pressure head 53. The pressure sensor 51 is connected to the side of the pressure plate 50 facing the stage 13. There are multiple pressure sensors 51 arranged in a circular array. The elastic connector 52 can extend and retract vertically. The elastic connector can be a spring. One end of the elastic connector 52 is connected to the detection end of the pressure sensor 51, and the pressure head 53 is connected to the other end of the elastic connector 52. The elastic connector 52 generates pressure on the sample target 14 through the pressure head 53.

[0097] Pressure sensors 51 are arranged in a circular array on the bottom surface of the pressure plate 50, for example, nine pressure sensors 51 are arranged, each spaced 40° apart. The detection end of each sensor is connected to an elastic connector 52, and the lower end of the elastic connector 52 is connected to a hemispherical pressure head 53 made of rubber. When the pressure plate 50 is placed above the sample target 14, the distance between the pressure plate 50 and the sample target 14 is controlled so that the pressure head 53 contacts the top surface of the sample target 14 and generates pressure. The elastic connector 52 is compressed and generates elastic force, applying a uniform pre-pressure to the sample target 14 through the pressure head 53. If the top surface of the sample target 14 is horizontal, the compression of each elastic connector 52 is the same, and the pressure sensor detection values ​​are consistent. If the sample target 14 is tilted, the compression of the elastic connector 52 of the pressure head 53 at the higher position is smaller (lower pressure value), and the compression of the elastic connector 52 of the pressure head 53 at the lower position is larger (higher pressure value).

[0098] Optionally, an outer support 15 is connected to the pressure plate 50. When it is necessary to test the levelness of the sample target 14, the pressure plate 50 is moved above the sample target 14 via the outer support 15. After the test is completed, the outer support 15, the pressure plate 50, and other structures on the pressure plate 50 are removed, leaving the top surface of the sample target 14 unobstructed, facilitating subsequent testing of the sample target 14. The outer support 15 can be connected to a horizontal track or other structure, allowing the pressure plate 50 to slide above the sample target 14 while maintaining a good levelness.

[0099] The tilt of the sample target 14 can be detected by the array of pressure sensors 51. The rubber indenter 53 and the elastic connector 52 are designed to cushion the surface of the sample target 14, preventing indentations or damage and protecting its integrity. The pressure plate 50 can be quickly installed and removed via a slot without affecting the clamping operation of the sample target 14.

[0100] In some other embodiments, the levelness detection mechanism includes a laser rangefinder. The laser rangefinder arranges multiple detection points in a circular manner around the top edge of the sample target 14 above the sample target 14, which can detect whether the top surface of the sample target 14 is tilted and the tilt direction, and can also calculate the tilt angle.

[0101] In one alternative embodiment, the shelf 13 includes an elastic element 131 and a shelf 132, the shelf 132 being connected to the elastic element 131, the elastic element 131 being connected to the base 10 and located in the middle of the cross groove 11. Optionally, the elastic element 131 can be a spring.

[0102] With the elastic element 131 and the placement plate 132 in place, the sample target 14 floats when placed on the placement plate 132. Pressing down on the placement plate 132 causes the sample target 14 to move downward, simultaneously placing the pressure plate 50 into the clamping space. Releasing the placement plate 132 allows it to rise under the support of the elastic element 131. The elastic connector 52 and the pressure head 53 then press the sample target 14 downward, keeping it constant. At this point, the elastic force of the elastic connector 52 is the same as the pressure of the elastic element 131, and the position of the sample target 14 is lower than the position when the elastic element 131 is not compressed. Therefore, the sample target 14 is in a suspended, fixed state, facilitating subsequent adjustment of its tilt.

[0103] The elastic element 131 is fitted inside the telescopic sleeve, and the elastic element 131 fits against the inner wall of the telescopic sleeve, so that the lifting and lowering of the elastic element 131 remains stable and does not tilt. The telescopic sleeve consists of two interlocking cylinders, one of which is connected to the base 10 and the other is connected to the shelf 132.

[0104] In one optional embodiment, the leveling mechanism includes an adjusting screw 60, a top rod 61, and a top ring. The top of the clamping rod 12 has a plug hole, and the adjusting screw 60 is rotatably connected to the top of the plug hole. The side wall of the clamping rod 12 facing the center of the cross slide groove 11 has a top groove, which is a vertically arranged elongated strip. The vertical length of the top groove is the longitudinal height adjustment range of the top rod 61. The top groove is connected to the plug hole, and the adjusting screw 60 is threadedly connected to the top ring. The top ring is located inside the plug hole, and the side wall of the top ring is connected to the top rod 61. The top ring can move axially along the plug hole under the limitation of the top rod 61. One end of the top rod 61 is slidably connected to the top groove, and the other end of the top rod 61 extends into the clamping space. The top rod 61 is located below the shelf 132, and the height of the top rod 61 can be adjusted vertically along the axis of the clamping rod 12 within the top groove. When it is necessary to adjust the level of the top surface of the sample target 14 by adjusting the height of the top rod 61 at the corresponding position, the level of the top surface of the sample target 14 can be adjusted by adjusting the level of the placement plate 132.

[0105] It should be noted that the placement plate 132 is a circular plate, the diameter of which is smaller than the diameter of the sample target 14. The length of the push rod 61 can be appropriately increased so that the lateral extension end of the push rod 61 is located below the edge of the placement plate 132, and when the four clamping rods 12 clamp the outer circumference of the sample target 14, they will not clamp the placement plate 132, ensuring that even a smaller sample target can be clamped and fixed by the clamping structure. The diameter of the circular plate and the lateral extension length of the push rod 61 can be set according to actual needs.

[0106] The leveling mechanism is integrated on four clamping rods 12. Each clamping rod 12 has a vertical insertion hole at its top. A rotating ring is sleeved on the side wall of the adjusting screw 60. The adjusting screw 60 is rotatably connected to the rotating ring, which is connected to the inner wall of the top of the insertion hole, allowing the adjusting screw 60 to rotate. The top of the adjusting screw 60 has a handle for easy operation. The inner wall of the top ring has an internal thread that matches the adjusting screw 60. When the adjusting screw 60 is rotated, the top ring moves axially along the insertion hole under the limit of the top rod 61. At the same time, the top ring drives the top rod 61 to move upward or downward (along the axial direction of the insertion hole). The top rod 61 lifts the corresponding position of the placement plate 132 to achieve local height adjustment. When the adjusting screw 60 is rotated in the opposite direction to the limit of the rotation position, the top rod 61 returns to its original position. Moreover, within the maximum height adjustment range, the top of the leveling mechanism is also lower than the top surface of the sample target 14, ensuring normal analysis and detection of the sample target test surface. Precise control of the displacement of the push rod 61 is achieved through threaded transmission, which, together with the stage 13, ensures the good levelness of the sample target 14, meeting the requirements for crystal orientation analysis such as electron backscatter diffraction. The leveling mechanisms of the four clamping rods 12 operate independently, allowing adjustment of the height of the four corners of the stage 132 to accommodate complex tilt conditions.

[0107] Specifically, the elastic force of the elastic connector 52 is the same as the pressure of the elastic member 131, and the sample target 14 is positioned lower than the position of the elastic member 131 when it is not compressed. Therefore, the sample target 14 is in a suspended and fixed state. At this time, the push rod 61 is located at the lower edge of the sample target 14. After the pressure detection sensor 51 detects different values ​​of the elastic connector 52, the tilt position of the sample target 14 is determined. If the tilt direction of the sample target 14 corresponds exactly to the position of the push rod 61 on one of the adjusting screws 60, the adjusting screw 60 can be rotated, and the push rod 61 moves axially along the insertion hole. The push rod 61 moves upward, and after the push rod 61 abuts against the placement plate 132, it lifts one end of the placement plate 132 and moves it upward. At the same time, the pressure value of the pressure detection sensor 51 is observed. When the pressure value in this direction is within a predetermined range compared with the values ​​of the multiple pressure detection sensors 51 on the periphery, the sample target 14 is determined to be horizontal, and the pressure plate 50 and the pressure detection sensor 51 are removed.

[0108] If the tilt direction of the sample target 14 is between the two adjusting screws 60, the corresponding two adjusting screws 60 can be controlled to drive the top ring and top rod 61 to move upward, lifting the sample target 14 upward. Simultaneously, the pressure value of the pressure detection sensor 51 is observed. After the values ​​of multiple pressure detection sensors 51 are within a predetermined range, the sample target 14 is determined to be horizontal. In this embodiment, it is also possible to directly adjust several adjusting screws 60 near the abnormal pressure detection sensor 51 based on the abnormal value, and try multiple adjustments to adjust the sample target 14 to a horizontal state.

[0109] This application also provides a method for using a sample stage for a scanning electron microscope, which differs from the method for using a sample stage for a scanning electron microscope in Embodiment 1 in that a leveling step S2A of the top surface of the sample target 14 is included between steps S2 and S3:

[0110] Step S2A specifically includes:

[0111] After the sample target 14 is placed on the stage 13, the levelness of the top surface of the sample target 14 on the stage 13 is detected by the levelness detection mechanism. Based on the detection result, the levelness of the top surface of the sample target 14 is adjusted by the leveling mechanism until the top surface of the sample target 14 is adjusted to a level or basically level state.

[0112] After leveling the top surface of the sample target 14, the leveled sample target is clamped and fixed in place by the clamping structure.

[0113] Compared with the prior art, the scanning electron microscope sample stage and its usage method provided in this embodiment, in addition to having the beneficial effects of Embodiment 1, also realize the horizontal adjustment of the top surface of the sample target through a leveling mechanism and a levelness detection mechanism. Especially for sample targets with uneven top / bottom surfaces or uneven axial thickness, the detection area can be kept horizontal through local height adjustment, thus expanding the applicability of the sample stage. This application solves the problem that the sample target is prone to tilting and unevenness after installing irregular cylindrical sample targets in traditional sample stages. This application can control the levelness of the top surface of the sample target within a predetermined reasonable range, ensuring that the electron beam of the scanning electron microscope is perpendicularly incident on the top surface of the sample target, and avoiding image distortion and elemental analysis errors caused by tilting.

[0114] The above specific embodiments further illustrate the purpose, technical solution and beneficial effects of this application. It should be understood that the above are only specific embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A sample stage for a scanning electron microscope, characterized in that, It includes a base and a clamping structure disposed on the base; the clamping structure has a clamping space and a shelf disposed inside the clamping space; The axis of the clamping space coincides with the axis of the sample target mounted on the stage, and the size of the clamping space is adjustable to accommodate sample targets of different sizes. The top opening of the clamping space allows the sample target to be installed to be placed on the stage from the top opening of the clamping space. The clamping structure also includes a driving mechanism and a clamping assembly. The clamping assembly has four vertically parallel clamping rods located on the same circumference and forming a clamping space above the base. The base has a cross-shaped sliding groove with four groove segments in four directions, and the lower ends of the four clamping rods are slidably disposed in the four groove segments respectively. The drive mechanism is located at the bottom of the base and is driven to connect with four clamping rods, which are used to drive the four clamping rods to synchronously move closer to or away from the axis of the clamping space in their respective slots. The drive mechanism includes a base, a first shaft, two winches, two stranded wires, an end face gear, a bevel gear, a second shaft, and a locking assembly. The base is connected to the base and located in the middle of the cross groove. The first shaft is connected to the base. The two winches and the end face gear are rotatably connected to the outer end of the first shaft. The second shaft passes through the base and is rotatable. One end of the second shaft is connected to a knob, and the other end is connected to the bevel gear, which meshes with the end face gear. The locking assembly is disposed on the second shaft and is used to lock and unlock the rotation of the second shaft. One stranded wire is connected to two opposing clamping rods arranged longitudinally in the cross groove and passes through the side wall of the inner winch. The other stranded wire is connected to two opposing clamping rods arranged transversely in the cross groove and passes through the side wall of the middle winch. It also includes a leveling mechanism and a levelness detection mechanism. The levelness detection mechanism is used to detect the levelness of the top surface of the sample target on the stage, and the leveling mechanism is used to adjust the levelness of the top surface of the sample target.

2. The scanning electron microscope sample stage according to claim 1, characterized in that, The clamping structure also has a knob, which is disposed on the base and coupled to the drive mechanism. The knob and the drive mechanism control the four clamping rods to move closer to or further away from the center of the cross groove to clamp or release the sample target on the stage.

3. The scanning electron microscope sample stage according to claim 1, characterized in that, The winch has a groove on its side wall and a hole on its side. The hole is located in the middle of the groove and forms two opposite openings in the groove. The stranded wire passes through the hole and is connected to the bottom end of the clamping rod.

4. The sample stage for scanning electron microscope according to claim 1, characterized in that, The locking assembly includes a locking nut, a locking washer, and a limiting plate. The limiting plate is connected to the bottom surface of the base near the inner wall of the base, and the second shaft passes through the limiting plate. The locking washer is disposed between the limiting plate and the inner wall of the base, and is in close contact with the limiting plate and the base. The locking washer is sleeved on the second shaft. The locking nut is disposed between the knob and the outer wall of the base. The second shaft has a thread between the knob and the locking washer, and the locking nut is threadedly connected to the second shaft.

5. The scanning electron microscope sample stage according to claim 4, characterized in that, The clamping structure also includes slide rails, which are respectively arranged on both sides of each groove segment. The side wall of the slide rail is provided with a sliding opening, and the side wall of the clamping rod is provided with two symmetrical sliding plates. The sliding plates are slidably connected to the sliding opening of one of the adjacent slide rails.

6. A method of using a scanning electron microscope sample stage as described in any one of claims 1 to 5, characterized in that, include: Step S1: Adjust the size of the clamping space of the clamping structure according to the size of the sample target, so that the size of the clamping space is larger than the diameter of the sample target; Step S2: Place the sample target onto the stage from the top opening of the clamping space; Step S3: readjust the size of the clamping space of the clamping structure, gradually reduce the size of the clamping space until the clamping assembly clamps and fixes the sample target, and completes the installation of the sample target; Step S4: After the test is completed, increase the size of the clamping space, and then directly remove the sample target to complete the sample target disassembly.

7. The method of using a scanning electron microscope sample stage according to claim 6, characterized in that, Between steps S2 and S3, there is also a sample target top surface leveling step S2A: After the sample target is placed on the stage, the levelness of the top surface of the sample target is detected by the levelness detection mechanism. Based on the detection results, the leveling mechanism is used to adjust the levelness of the top surface of the sample target until the top surface of the sample target is leveled.

Images