An atomic force microscope system

Abstract

The utility model discloses an atomic force microscope system, include: three -axis adjustable sample stage, optical fixed module, optical module, three -axis adjustable sample stage includes sample stage base, sample stage support and sample stage, sample stage base includes at least two pairs of first electroacoustic transducer who sets up along sample stage base center symmetry, sample stage support includes at least two pairs of first support foot with first electroacoustic transducer upper portion connects, and sample stage support still includes the first support end corresponding with first support foot, and first support end is fixedly connected with sample stage, be provided with second electroacoustic transducer on sample stage, and the upper portion of second electroacoustic transducer can place sample, optical fixed module is used for fixing optical module, so that the laser head of fixed optical module is directly opposite sample. The utility model can solve the technical problem of high cost and complex structure of the existing atomic force microscope system.

Description

Technical Field

[0001] This utility model relates to the field of atomic force microscopy technology, and in particular to an atomic force microscopy system. Background Technology

[0002] Atomic force microscopy (AFM), as one of the core technologies in scanning probe microscopy, is widely used in various precision engineering and basic research fields such as semiconductor manufacturing, materials science, biomedicine, and microelectronic device inspection due to its spatial resolution capabilities at the nanometer and even atomic levels. A traditional AFM system mainly consists of the following subsystems: First, a high-precision three-dimensional scanning drive system, typically employing multi-layered or tubular piezoelectric ceramic actuators to achieve nanometer-level motion control along the XYZ axes; second, a high-sensitivity optical detection system, mostly using beam deflection methods, which combines a laser and a four-quadrant photodetector to monitor minute deflection changes of the probe in real time, thereby providing feedback on surface morphology; third, a feedback control system, integrating a closed-loop PI / PID controller to stably and accurately adjust the Z-axis displacement to ensure imaging accuracy; fourth, a vibration isolation platform to eliminate environmental vibrations and improve the signal-to-noise ratio during scanning; and fifth, a high-performance host computer data acquisition and image processing system to achieve real-time data analysis and visualization.

[0003] However, traditional AFM systems are typically extremely expensive. For XYZ 3D scanning, the core hardware components of existing AFM systems rely on stacked or tubular piezoelectric ceramic actuators. While these actuators offer excellent displacement resolution and response speed, their manufacturing process involves a series of high-barrier industrial processes, including precision sintering, multi-layer electrode printing, and high-temperature polarization treatment, resulting in high unit costs. Furthermore, these devices typically operate within a voltage range of ±100V or even higher, significantly limiting the application areas of AFM.

[0004] Secondly, regarding the optical detection system, while the beam deflection method widely used in traditional AFM has high detection sensitivity, its implementation relies on a variety of high-cost components, including highly stable laser diodes, precision lens groups, high-response-speed four-quadrant photodetectors, and mechanical fine-tuning platforms. Furthermore, the entire optical path alignment process requires manual adjustment to achieve sub-micron level coaxial accuracy, which is difficult and time-consuming. In addition, to ensure the system's stability, a temperature control system and a sealed optical chamber are typically required, further increasing the overall size and cost of the AFM system.

[0005] Finally, existing AFM systems have significant shortcomings in terms of lightweight design and portability. Due to their multi-layered stacked scanning actuators and the need for high-power power supply and cooling systems, the entire unit is bulky and heavy, often requiring operation on a fixed platform and lacking portability. This directly limits their flexibility in applications such as industrial product field testing, experimental sample analysis, and small to medium-sized laboratories.

[0006] As can be seen from the above issues, although the current mainstream AFM system has matured in terms of technical performance indicators, it still has obvious shortcomings in terms of cost control, structural complexity, application threshold, and lightweight design. Utility Model Content

[0007] This invention provides an atomic force microscope system to solve the technical problems of high cost and complex structure of existing atomic force microscope systems.

[0008] According to one aspect of the present invention, an atomic force microscope system is provided, comprising: Three-axis adjustable sample stage, optical fixation module, optical module; The triaxial adjustable sample stage includes a sample stage base, a sample stage support, and a sample stage. The sample stage base includes at least two pairs of first electroacoustic transducers symmetrically arranged along the center of the sample stage base. The sample stage support includes at least two pairs of first support legs connected to the upper part of the first electroacoustic transducer, and the number of the first support legs is the same as the number of the first electroacoustic transducers; the sample stage support also includes a first support end corresponding to the first support leg, and the first support end is fixedly connected to the sample stage. A second electroacoustic transducer is provided on the sample stage, and a sample can be placed on the upper part of the second electroacoustic transducer; The optical fixing module is used to fix the optical module so that the laser head of the fixed optical module is facing the sample. Optionally, the sample stage base includes two pairs of first electroacoustic transducers symmetrically arranged along the center of the sample stage base; the first electroacoustic transducers are fixedly connected to the sample stage base. The sample stage support includes two pairs of first support legs connected to the upper part of the first electroacoustic transducer; the sample stage support also includes a first support end corresponding to the first support leg, and the first support end is fixedly connected to the sample stage; a support rod is fixedly provided between the first support ends corresponding to each pair of first support legs, and the sample stage can be placed on the upper part of the support rod. One of the support rods has a first locking groove on its first side, and the other support rod has a second locking groove on its second side, so that the two support rods are assembled by interlocking with each other through the first locking groove and the second locking groove.

[0009] Optionally, the first support foot further includes a magnetic component, and the first support foot is connected to the upper part of the first electroacoustic transducer through the magnetic component.

[0010] Optionally, the sample stage edge is provided with multiple fixing slots at equal intervals, the same number as the first support ends, for fixing and connecting to each of the first support ends respectively.

[0011] Optionally, the optical fixing module includes a fixing bracket and a fixing platform, wherein the fixing bracket includes at least two pairs of second bracket legs and at least two pairs of second support ends corresponding to the at least two pairs of second bracket legs; The second support leg is fixedly connected to the sample stage base, and the second support end is fixedly connected to the fixed platform; The optical module includes an optical component mounting platform and an optical module mounted on the optical component mounting platform. The fixed platform is connected to the mounting platform for the optical components via adjustable screws, and the laser head of the optical module on the optical module is facing the sample after installation.

[0012] Optionally, the fixed bracket includes two pairs of second bracket legs and two pairs of second support ends; Four fixing slots corresponding to the second support legs are equally spaced at the edge of the sample stage base for fixing and connecting to each of the second support legs respectively. The fixed platform is provided with four equally spaced fixing slots corresponding to the second support end, which are used to fix and connect to each of the second support ends respectively. A second support rod is fixedly provided between each pair of second support legs, and the lower part of the support rod can be placed on the sample stage base; a third locking groove is provided on the third side of one second support rod, and a fourth locking groove is provided on the fourth side of the other second support rod, so that the two second support rods are assembled by interlocking with each other through the third locking groove and the fourth locking groove.

[0013] Optionally, the fixed platform includes a hollow hole, the area of ​​which is larger than the area of ​​the sample stage; The fixed platform is provided with at least three first screw holes, and the optical component mounting platform is provided with at least three second screw holes. The fixed platform and the optical component mounting platform are connected by at least three adjustable screws, the first screw holes and the second screw holes. After installation, the optical component mounting platform is higher than the sample stage, and the plane of the optical component mounting platform is parallel to the plane of the sample stage base.

[0014] Optionally, the at least three first screw holes include at least one circular screw hole and at least one elongated screw hole.

[0015] Optionally, a microcantilever is also provided on the sample stage; the first end of the microcantilever is fixed on the sample stage, and a probe is provided on the second end, the tip of which can contact the sample.

[0016] Optionally, a control module is included, which is electrically connected to the first electroacoustic transducer and the second electroacoustic transducer respectively, to control the vibration of the first electroacoustic transducer and the second electroacoustic transducer respectively.

[0017] The technical solution of this utility model embodiment uses at least two pairs of first electroacoustic transducers symmetrically arranged at the center of the sample stage base of a three-axis adjustable sample stage. First support feet connected to the upper part of the first electroacoustic transducers are fixedly connected to the sample stage, and corresponding first support ends are fixedly connected to the sample stage. This allows control of the vibration of a pair of electroacoustic transducers to control the offset of a pair of first support ends in the linear direction of the pair of electroacoustic transducers, thereby causing the three-axis adjustable sample stage to shift in the linear direction of the pair of electroacoustic transducers. Furthermore, by providing a second electroacoustic transducer on the sample stage, a sample can be placed on top of the second electroacoustic transducer, allowing the sample to vibrate up and down with the vibration of the second electroacoustic transducer, thereby controlling the distance between the sample and the probe.

[0018] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1This is a structural diagram of a triaxially adjustable sample stage in an atomic force microscope system according to Embodiment 1 of this utility model; Figure 2 This is a structural diagram of the assembled triaxial adjustable sample stage and optical fixing module in an atomic force microscope system according to Embodiment 1 of this utility model; Figure 3 This is a schematic diagram of the sample stage base in one embodiment of the present invention; Figure 4 This is a schematic diagram of a sample stage support in one embodiment of the present invention; Figure 5 This is a schematic diagram of the sample stage in one embodiment of the present invention; Figure 6 This is a schematic diagram of the motion scanning of the buzzer-shaped scanner in one embodiment of this utility model; Figure 7 This is a schematic diagram of the fixing bracket of the optical fixing module in one embodiment of this utility model; Figure 8 This is a schematic diagram of the fixing platform of the optical fixing module in one embodiment of this utility model; Figure 9 This is a schematic diagram of the optical module in one embodiment of the present invention; Figure 10 This is a physical image of the three-axis adjustable sample stage and optical fixing module after they have been fixed in one embodiment of this utility model; Figure 11 This is a physical image of an atomic force microscope system according to one embodiment of the present invention; Figure 12 This is a schematic diagram of the optical pickup detection principle in one embodiment of this utility model.

[0021] Figure label: Three-axis adjustable sample stage-1; Optical fixing module-2; Optical module-3; Adjustable screw-4; Control module-5; Sample stage base-11; Sample stage bracket-12; Sample stage-13; First electroacoustic transducer-14; Second electroacoustic transducer-15; First bracket foot-121; First support end-122; Support rod-123; First locking slot-1231; Second locking slot-1232; Third locking slot-231; Fourth locking slot-232; Fixing platform-24; First screw hole-241; Hollow hole-242; Optical component mounting platform-31; Second screw hole-311; Optical module-32; Laser head-321. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] Example 1 Figure 1 A structural diagram of an atomic force microscope system is provided for Embodiment 1 of this utility model. (See diagram below.) Figure 1 As shown, the atomic force microscope system includes: Three-axis adjustable sample stage 1, optical fixing module 2, optical module 3; The triaxial adjustable sample unit includes a sample stage base 11, a sample stage support 12, and a sample stage 13; The sample stage base 11 includes at least two pairs of first electroacoustic transducers 14 symmetrically arranged along the center of the sample stage base. The sample stage support 12 includes at least two pairs of first support legs 121 connected to the upper part of the first electroacoustic transducer 14, and the number of first support legs 121 is the same as that of the first electroacoustic transducer; the sample stage support 12 also includes a first support end 122 corresponding to the first support legs 121, and the first support end 122 is fixedly connected to the sample stage 13. A second electroacoustic transducer 15 is provided on the sample stage, and a sample can be placed on the upper part of the second electroacoustic transducer 15. The optical fixing module 2 is used to fix the optical module 3 so that the laser head 31 of the fixed optical module 3 faces the sample. Figure 1The three-axis adjustable sample stage 1 includes a sample stage base 11, a sample stage support 12, and a sample stage 13. The sample stage base 11 can be set as a circle, a square, or a regular polygon, etc.

[0025] The sample stage base 11 includes at least two pairs of first electroacoustic transducers 14 symmetrically arranged along the center of the sample stage base; the sample stage base 11 can be fixedly connected to at least two pairs of first electroacoustic transducers 14, and at least two pairs of first electroacoustic transducers 14 can be controlled to vibrate, and each first electroacoustic transducer 14 can be controlled individually.

[0026] Figure 1 It includes two pairs of first electroacoustic transducers 14, and the straight line connecting one pair of first electroacoustic transducers 14 is perpendicular to the straight line connecting the other pair of first electroacoustic transducers 14; it can be regarded that the straight line connecting the first pair of first electroacoustic transducers 14 is the X direction, and the straight line connecting the other pair of first electroacoustic transducers 14 is the Y direction. Figure 1 This is merely an illustrative example. In practice, this embodiment can provide multiple pairs of first electroacoustic transducers 14, such that after N pairs of first electroacoustic transducers 14 are installed, the angle between the straight line connecting each pair of first electroacoustic transducers 14 and the straight line connecting the adjacent pair of first electroacoustic transducers 14 is 360 degrees / 2N.

[0027] The sample stage support 12 in this embodiment includes at least two pairs of first support legs 121 connected to the upper part of the first electroacoustic transducer 14, the number of first support legs 121 being the same as the number of first electroacoustic transducers; and the sample stage support 12 also includes a first support end 122 corresponding to the first support leg 121, the first support end 122 being fixedly connected to the sample stage 13. It should be noted that, since the first support leg 121 is connected to the upper part of the first electroacoustic transducer 14, when the first electroacoustic transducer 14 vibrates, the first support leg 121 will also move with the first electroacoustic transducer 14. Suppose a positive voltage is applied to one of the pair of first electroacoustic transducers 14 (which can be considered as a positive displacement), and a reverse voltage is applied to the other first electroacoustic transducer 14 (which can be considered as a reverse displacement). Then, the movement of the first support foot 121 connected to this pair of first electroacoustic transducers 14 will cause the sample stage support 12 to tilt at a certain angle, thereby controlling the sample stage support 12 to deflect along the straight line where this pair of first electroacoustic transducers 14 are located.

[0028] A second electroacoustic transducer 15 is provided on the sample stage. A sample can be placed on the upper part of the second electroacoustic transducer 15. The vibration of the second electroacoustic transducer 15 can be controlled to cause the sample to move along the Z-axis, thereby controlling the distance between the sample and the probe.

[0029] The atomic force microscope system in this embodiment also includes an optical fixation module 2, which is used to fix the optical module 3 so that the laser head 321 of the fixed optical module 3 faces the back of the probe, so that the generated laser beam can be emitted to the back of the probe. When the tip of the probe contacts the sample, the first electroacoustic transducer 14 is controlled to cause the sample stage 13 to shift horizontally, and the second electroacoustic transducer 15 is controlled to cause the sample stage 13 to shift vertically. This causes the sample on the second electroacoustic transducer 15 to also shift horizontally and vertically. At this time, the probe can move and deflect on the sample, and the position of the reflected beam shifts accordingly. The photodetector on the optical module 3 can receive the shifted reflected beam and thus identify the surface morphology of the sample.

[0030] The technical solution of this utility model embodiment uses at least two pairs of first electroacoustic transducers symmetrically arranged at the center of the sample stage base of a three-axis adjustable sample stage. First support feet connected to the upper part of the first electroacoustic transducers are fixedly connected to the sample stage, and corresponding first support ends are fixedly connected to the sample stage. This allows control of the vibration of a pair of electroacoustic transducers to control the offset of a pair of first support ends in the linear direction of the pair of electroacoustic transducers, thereby causing the three-axis adjustable sample stage to shift in the linear direction of the pair of electroacoustic transducers. Furthermore, by providing a second electroacoustic transducer on the sample stage, a sample can be placed on top of the second electroacoustic transducer, allowing the sample to vibrate up and down with the vibration of the second electroacoustic transducer, thereby controlling the distance between the sample and the probe.

[0031] In a preferred embodiment, the sample stage base 11 includes two pairs of first electroacoustic transducers 14 symmetrically arranged along the center of the sample stage base 11; the first electroacoustic transducers 14 are fixedly connected to the sample stage base 11; the sample stage support 12 includes two pairs of first support legs 121 connected to the upper part of the first electroacoustic transducers 14; the sample stage support 12 also includes first support ends 122 corresponding to the first support legs 12, and the first support ends 122 are fixedly connected to the sample stage 13; a support rod 123 is fixedly arranged between the first support ends 122 corresponding to each pair of first support legs 122, and the sample stage 13 can be placed on the upper part of the support rod 123; a first locking groove 1231 is provided on the first side of one support rod 123, and a second locking groove 1232 is provided on the second side of the other support rod, so that the two support rods are assembled by interlocking with each other through the first locking groove 1231 and the second locking groove 1232.

[0032] like Figure 3The schematic diagram of the sample stage base 11 in one embodiment shows that the sample stage base 11 includes two pairs of first electroacoustic transducers 14 symmetrically arranged along the center of the sample stage base 11. Fixing slots for the two pairs of first electroacoustic transducers 14 symmetrically arranged along the center of the sample stage base 11 can be provided. Each fixing slot may include a circular slot, and the edge of the circular slot is further provided with multiple arc-shaped grooves. The shape of the circular slot corresponds to the shape of the first electroacoustic transducer 14, used for installing the first electroacoustic transducer 14. The multiple arc-shaped grooves serve as welding points for the first electroacoustic transducers 14 to fix them. In this embodiment, the radius of the sample stage base 11 can be set to 50 mm, the inner diameter of the four circular slots to be 23 mm, and the outer diameter to be 26 mm. The inner diameter of the arc-shaped grooves is 1.8 mm, and the outer diameter is 3.2 mm.

[0033] like Figure 4 The schematic diagram of the sample stage support 12 shown is used to connect the first electroacoustic transducer 14 and the sample stage 13. Specifically, it includes two pairs of first support feet 121 connected to the upper part of the first electroacoustic transducer 14. Each first support foot 121 also includes a magnetic component, and the first support foot 121 is connected to the upper part of the first electroacoustic transducer via the magnetic component, causing the first support foot 121 to move up and down with the vibration of the first electroacoustic transducer 14. In this embodiment, the overall height of the sample stage support 12 can be set to 88.5 mm, the width to 57.97 mm, and the length and width of the interlocking portion to be 4 mm and 2.2 mm, respectively.

[0034] The sample stage support 12 also includes a first support end 122 corresponding to the first support leg 12, and the first support end 122 is fixedly connected to the sample stage 13. Specifically, the sample stage 13 has multiple fixing slots 131 at equal intervals along its edge, the same number as the number of first support ends 122, for fixed connection to each first support end 122 respectively. A schematic diagram of the sample stage 13 is shown below. Figure 5 As shown, Figure 5 The sample stage 13 includes a fixing slot corresponding to the size of the second electroacoustic transducer 15. Each fixing slot may include a circular slot, and the edge of the circular slot is also provided with multiple arc-shaped grooves for welding the second electroacoustic transducer 15. The radius of the entire circular sample stage 13 can be set to 29mm, and the parameters of the arc-shaped grooves and the circular slots are the same as those of the arc-shaped grooves and the circular slots on the sample stage base 11.

[0035] like Figure 4The schematic diagram of the sample stage support 12 shown shows that a support rod 123 is fixedly provided between the first support ends 122 corresponding to each pair of first support legs 122, and the sample stage 13 can be placed on the upper part of the support rod 123. A first locking groove 1231 is provided on the first side of a support rod 123, and a second locking groove 1232 is provided on the second side of another support rod, so that the two support rods 123 are assembled by interlocking with each other through the first locking groove 1231 and the second locking groove 1232. The sample stage 13 can be placed on the support rod 123 of the assembled sample stage bracket 12, and the four first support ends 122 are respectively welded to the four fixing grooves 131 of the sample stage 13, thereby fixing the sample stage 13 and the sample stage bracket 12. When the first electroacoustic transducer 14 vibrates, the sample stage bracket 12 connected to the first electroacoustic transducer 14 will follow the four first electroacoustic transducers 14 to perform two-axis movement (it can be considered that the straight line where one pair of first electroacoustic transducers 14 is located is the X-axis, and the straight line where the other pair of first electroacoustic transducers 14 is located is the Y-axis). Specifically, the vibration displacement of the first electroacoustic transducers 14 can be controlled by applying driving voltages with opposite phases to the two first electroacoustic transducers 14, thereby creating a micrometer-level height difference between the two first electroacoustic transducers 14 at the same time, which in turn causes the sample stage 13 to produce a micrometer-level lateral displacement in the plane. The Z-axis is independently controlled by a vertically mounted second electroacoustic transducer 15, with the driving direction perpendicular to the sample surface, used to adjust the distance between the probe and the sample, realizing closed-loop feedback control in the Z-axis direction.

[0036] In this embodiment, both the first electroacoustic transducer 14 and the second electroacoustic transducer 15 can be buzzers of equal size. These buzzers offer significant advantages such as extremely low cost, small size (approximately 0.2 mm thick, less than 20 mm in diameter), and low power consumption (driving voltage only ±10V), greatly reducing the AFM system's dependence on high-voltage linear amplifiers and high-end piezoelectric devices. Furthermore, by optimizing structural symmetry and voltage drive waveform parameters, this system effectively suppresses multi-axis coupling and hysteresis, achieving a minimum step resolution of 2.685 nm within an 11×11 μm scan range, meeting the requirements of most engineering-grade surface characterization.

[0037] Its specific principle is as follows Figure 6 As shown, when opposite-phase voltages are applied to the symmetrical buzzer sector electrodes, the deformation of a pair of buzzers (X, -X) causes a lateral displacement of the sample holder along the X-axis. Vertical linear deformation of the two circular buzzer plates This causes the scanner to tilt at an angle θ. The relationship between the lateral displacement and the vertical deformation of the buzzer plate can be derived as follows:

[0038] Where l is the distance from the first electroacoustic transducer 14 to the second electroacoustic transducer 15; r is the perpendicular distance from the axis containing the center of the first electroacoustic transducer 14 to the axis containing the center of the second electroacoustic transducer 15.

[0039] The same principle of motion applies to displacement in the Y direction. In scanning motion control, the scanning path is from the initial point (0, 0) to (X, 0). This process is accomplished by adjusting the buzzer in the X direction. After a single scan, the probe quickly returns to the initial point (0, 0). At this point, the buzzer in the Y direction deforms, and the probe reaches (0, 0). The first scan is repeated, and so on, until the scan is complete. Scanning can also be done by direct back-and-forth movement, but if the sample stage is controlled to move directly back and forth, due to differences in the manufacturing process of the buzzer and the inherent nonlinear effects such as hysteresis and creep of the piezoelectric ceramic sheet, as well as the cross-coupling problem caused by simultaneous X and Y movement, obvious stripes will appear in the final scan image. Using a single-line scan method not only avoids cross-coupling in the X and Y directions and eliminates the uneven displacement problem caused by differences in the manufacturing process of the two buzzers on the X (or Y) axis, but also greatly reduces the stripes in the final scan image because each line of the scan is driven in the same way, significantly improving scanning performance.

[0040] In a preferred embodiment, the optical fixing module 2 includes a fixing bracket and a fixing platform 23. The fixing bracket includes at least two pairs of second bracket legs 21 and at least two pairs of second support ends 22 corresponding to the at least two pairs of second bracket legs 21. The second bracket legs 21 are fixedly connected to the sample stage base 11, and the second support ends 22 are fixedly connected to the fixing platform 23. The optical module 3 includes an optical component mounting platform 31 and an optical module 32 mounted on the optical component mounting platform. The fixing platform 24 is connected to the optical component mounting platform 31 via adjustable screws 4, and the laser head 321 of the optical module 32 on the optical module 3, after installation, faces the sample.

[0041] like Figure 2 , Figure 7 and Figure 8As shown, the optical fixing module 2 includes a fixing bracket and a fixing platform 24. The fixing bracket includes at least two pairs of second bracket legs 21 and at least two pairs of second support ends 22 corresponding to the at least two pairs of second bracket legs 21. In a preferred embodiment, the fixing bracket includes two pairs of second bracket legs 21 and two pairs of second support ends 22; four fixing slots corresponding to the second bracket legs 21 are equally spaced at the edge of the sample stage base for fixing to each second bracket leg 21; four fixing slots corresponding to the second support ends 21 are equally spaced on the fixing platform for fixing to each second support end; a second support rod 23 is fixedly arranged between each pair of second bracket legs 21, and the lower part of the support rod can be placed on the sample stage base 11; a third locking groove 231 is provided on the third side of one second support rod 23, and a fourth locking groove 232 is provided on the fourth side of the other second support rod 23, so that the two second support rods 23 are assembled by interlocking with each other through the third locking groove 231 and the fourth locking groove 232.

[0042] Specifically, the second support rod 23 of the fixed bracket may also include multiple circular holes for circuit wiring. In this embodiment, the bracket height of the fixed bracket can be set to 93mm, wherein the height of the second support end 22 can be set to 5mm, and the second bracket foot 21 can be set to 1.5mm. The width of the fixed bracket can be set to 100mm, and the length of the interlocking third and fourth locking slots 231 and 232 can be set to 29mm, and the width can be set to 2.2mm.

[0043] In such Figure 8 In the embodiment shown, the fixed platform 24 includes a hollow hole 242 with an area larger than that of the sample stage 13, such that after the fixed platform 24, sample stage base 11, sample stage support 12, and sample stage are assembled, the sample stage 13 is located in the hollow hole 242 of the fixed platform 24. A schematic diagram of the assembled assembly is shown below. Figure 2 As shown. The fixed platform 24 is provided with at least three first screw holes 241, and the optical component mounting platform 31 is provided with at least three corresponding second screw holes 311. The fixed platform 24 and the optical component mounting platform 31 are connected via at least three adjustable screws, the first screw holes 241, and the second screw holes 311. After installation, the optical component mounting platform 31 is higher than the sample stage 13, and the plane of the optical component mounting platform 31 is parallel to the plane of the sample stage base 11. In this embodiment, the actual object after the fixed platform 24, sample stage base 11, sample stage support 12, and sample stage are installed is shown in the figure. Figure 10 As shown.

[0044] In a preferred embodiment, the at least three first screw holes 241 include at least one circular screw hole and at least one elongated screw hole.

[0045] The elongated screw hole allows for some extra space during tightening, enabling the screw to be adjusted so that the plane of the optical component mounting stage 31 is parallel to the plane of the sample stage base 11. In this embodiment, high-precision adjustable screws are used, allowing for minute adjustments to focus the optical module 32 and ensure the plane of the optical component mounting stage 31 is parallel to the plane of the sample stage base 11.

[0046] like Figure 9 The schematic diagram of the optical module 3 shown includes an optical component mounting platform 31 and an optical module 32 mounted on the optical component mounting platform; the fixed platform 23 is connected to the optical component mounting platform 31 by an adjustable screw 4, and the laser head 321 of the optical module 32 on the optical module 3 is facing the sample after installation.

[0047] In a preferred embodiment, a microcantilever is also provided on the sample stage 13; the first end of the microcantilever is fixed on the sample stage, and a probe is provided on the second end, the tip of which can contact the sample.

[0048] It should be noted that the laser head 321 of the optical module 32 can focus the laser onto the back of the probe. By controlling the vibration of four first electroacoustic transducers 14 and one second electroacoustic transducer 15 respectively, the sample stage can be controlled to undergo three-axis micro-motion. This causes the reflected beam to shift position when the probe is deflected due to surface forces, and is ultimately received by a four-quadrant photodetector on the optical module 32, which converts it into an electrical signal to characterize the degree of probe deflection. The assembled atomic force microscope system in this embodiment is shown in the image below. Figure 11 As shown.

[0049] In a preferred embodiment, a control module 5 is further included. The control module 5 is electrically connected to the first electroacoustic transducer 14 and the second electroacoustic transducer 15, respectively, to control the vibration of the first electroacoustic transducer 14 and the second electroacoustic transducer 15.

[0050] Specifically, in this embodiment, the optical detection module incorporates an astigmatic optical pickup commonly found in optical drive reading devices. This pickup integrates a laser diode, collimating lens, astigmatic cylindrical lens, beam splitter, and four-quadrant photodetector, enabling the acquisition of high-frequency vibration signals with a focused spot size of less than 1 μm and a bandwidth of up to 25 MHz. Its core working principle utilizes the cylindrical lens to introduce axial astigmatism. When the laser is reflected back to the OPU, different spot shapes (elliptical or circular) are formed based on changes in the focal error (FES). After sampling by the four-quadrant photodetector, the minute Z-axis displacement is converted into a voltage signal. This module is not only compact and has a standardized interface, requiring no additional optical debugging, but it is also extremely inexpensive, significantly simplifying the structural design and assembly process of the optical measurement section in the AFM system. It is a key technological aspect for achieving cost reduction and module integration.

[0051] like Figure 12 As shown, a four-quadrant photodetector converts the intensity distribution of reflected light incident on the surface into four electrical signal outputs. The four quadrants of the four-quadrant photodetector are named A, B, C, and D. After introducing astigmatism into the optical path, the long axis direction of the light spot changes near the focal point. This change can be characterized by focusing error, which can be expressed as:

[0052] When the focus is correct, the reflected light, after passing through the cylindrical lens, forms a circular spot on the detector plane, resulting in a focusing error of 0. When the focus is too close, the spot is elongated vertically into an elliptical shape, incident on quadrants A and C of the photodetector, resulting in a positive focusing error. When the focus is too far, the sample is below the focal plane, and the spot is elongated horizontally, incident on quadrants B and D of the photodetector, resulting in a negative focusing error. By measuring the focusing error, the true position of the focus can be obtained. Combined with the negative feedback adjustment mechanism of the circuit, high-speed and stable focusing of the optical disc can be achieved.

[0053] In terms of system structure, this utility model designs a rigid support platform structure based on the three-point contact principle. Three adjustable high-precision screws and three sets of grooved columns are fitted together to form a stable fixed surface, which effectively constitutes a three-dimensional six-degree-of-freedom constraint system. This ensures the stability of the optical components during the scanning process and also enables focusing of the laser of the optical module and the sample part of the scanning module.

[0054] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. An atomic force microscope system, characterized in that, include: Three-axis adjustable sample stage, optical fixation module, optical module; The triaxial adjustable sample stage includes a sample stage base, a sample stage support, and a sample stage. The sample stage base includes at least two pairs of first electroacoustic transducers symmetrically arranged along the center of the sample stage base. The sample stage support includes at least two pairs of first support legs connected to the upper part of the first electroacoustic transducer, and the number of the first support legs is the same as the number of the first electroacoustic transducers; the sample stage support also includes a first support end corresponding to the first support leg, and the first support end is fixedly connected to the sample stage. A second electroacoustic transducer is provided on the sample stage, and a sample can be placed on the upper part of the second electroacoustic transducer; The optical fixing module is used to fix the optical module so that the laser head of the fixed optical module is facing the sample.

2. The atomic force microscope system according to claim 1, characterized in that, The sample stage base includes two pairs of first electroacoustic transducers symmetrically arranged along the center of the sample stage base; the first electroacoustic transducers are fixedly connected to the sample stage base. The sample stage support includes two pairs of first support legs connected to the upper part of the first electroacoustic transducer; the sample stage support also includes a first support end corresponding to the first support leg, and the first support end is fixedly connected to the sample stage; a support rod is fixedly provided between the first support ends corresponding to each pair of first support legs, and the sample stage can be placed on the upper part of the support rod. One of the support rods has a first locking groove on its first side, and the other support rod has a second locking groove on its second side, so that the two support rods are assembled by interlocking with each other through the first locking groove and the second locking groove.

3. The atomic force microscope system according to claim 2, characterized in that, The first support foot also includes a magnetic component, and the first support foot is connected to the upper part of the first electroacoustic transducer through the magnetic component.

4. The atomic force microscope system according to claim 1, characterized in that, The sample stage has multiple fixing slots at equal intervals along its edge, the same number as the first support end, for fixing and connecting to each of the first support ends respectively.

5. The atomic force microscope system according to claim 1, characterized in that, The optical fixing module includes a fixing bracket and a fixing platform. The fixing bracket includes at least two pairs of second bracket legs and at least two pairs of second support ends corresponding to the at least two pairs of second bracket legs. The second support leg is fixedly connected to the sample stage base, and the second support end is fixedly connected to the fixed platform; The optical module includes an optical component mounting platform and an optical module mounted on the optical component mounting platform. The fixed platform is connected to the mounting platform for the optical components via adjustable screws, and the laser head of the optical module on the optical module is facing the sample after installation.

6. The atomic force microscope system according to claim 5, characterized in that, The fixed bracket includes two pairs of second bracket legs and two pairs of second support ends; Four fixing slots corresponding to the second support legs are equally spaced at the edge of the sample stage base for fixing and connecting to each of the second support legs respectively. The fixed platform is provided with four equally spaced fixing slots corresponding to the second support end, which are used to fix and connect to each of the second support ends respectively. A second support rod is fixedly provided between each pair of second support legs, and the lower part of the support rod can be placed on the sample stage base; a third locking groove is provided on the third side of one second support rod, and a fourth locking groove is provided on the fourth side of the other second support rod, so that the two second support rods are assembled by interlocking with each other through the third locking groove and the fourth locking groove.

7. The atomic force microscope system according to claim 5, characterized in that, The fixed platform includes a hollow hole, the area of ​​which is larger than the area of ​​the sample stage; The fixed platform is provided with at least three first screw holes, and the optical component mounting platform is provided with at least three second screw holes. The fixed platform and the optical component mounting platform are connected by at least three adjustable screws, the first screw holes and the second screw holes. After installation, the optical component mounting platform is higher than the sample stage, and the plane of the optical component mounting platform is parallel to the plane of the sample stage base.

8. The atomic force microscope system according to claim 7, characterized in that, The at least three first screw holes include at least one circular screw hole and at least one elongated screw hole.

9. The atomic force microscope system according to claim 1, characterized in that, The sample stage is also equipped with a microcantilever; the first end of the microcantilever is fixed on the sample stage, and the second end is equipped with a probe, the tip of which can contact the sample.

10. The atomic force microscope system according to claim 1, characterized in that, It also includes a control module, which is electrically connected to the first electroacoustic transducer and the second electroacoustic transducer respectively, so as to control the vibration of the first electroacoustic transducer and the second electroacoustic transducer respectively.

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