High-sensitivity positioning atomic force microscope detection device and method

Abstract

This invention discloses a high-sensitivity positioning atomic force microscope (AFM) detection device and method, including a dark-field oblique incidence light source module, an open-type AFM scanning module, a microscopic imaging system, and a high-precision motion platform for placing the sample. The dark-field oblique incidence light source module provides a multi-angle oblique incidence light source to the sample, creating a dark-field effect, allowing the scattered light from micro-nano defects on the sample surface to be captured by the microscopic imaging system, achieving high-sensitivity positioning. The AFM scanning module includes a radio frequency modulated laser, a probe assembly, and a photodetector. The laser output from the laser irradiates the probe assembly and is reflected into the photodetector. The sample is a transparent element, and the positioning is achieved by adjusting the incident angle of the dark-field oblique incidence light source module, the refractive index of the sample, and the numerical aperture of the microscopic imaging system. NA The relationship is constrained to ensure that the imaging of the sample center and edges meets the dark field conditions. Using this invention, micro- and nano-scale surface defects can be accurately located during AFM detection.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of optical element detection, and in particular relates to a high-sensitivity positioning micro-nano defect atomic force microscope detection device and method. BACKGROUND

[0002] In the field of extreme optics such as inertial confinement fusion systems, high-end photolithography machines, and space telescopes, there is an increasing dependence on ultra-high precision optical elements. However, during ultra-precision machining, surface defects such as micro-nano scratches and pits are difficult to avoid. In extreme environments such as high-energy lasers, the local light field modulation caused by these defects may lead to damage points, reducing the laser damage threshold and greatly limiting the improvement of overall system optical performance and service life. Determining the three-dimensional topography of surface defects is beneficial for theoretical research on defect light field modulation.

[0003] Currently, methods for detecting the three-dimensional topography of surface defects include confocal microscopy, white light interferometry, structured light three-dimensional reconstruction, and non-optical detection methods such as atomic force microscopy (AFM) and profilometry. Due to the limitation of optical diffraction limit, optical methods are difficult to achieve high-precision three-dimensional reconstruction of micro-nano scale defects. AFM can achieve nanometer or even sub-nanometer precision in both horizontal and vertical directions, enabling high-precision three-dimensional imaging of defects.

[0004] The detection equipment of AFM usually needs to be equipped with additional auxiliary modules to position the defects to be tested. After determining the position of the target to be tested, the probe or sample is moved for three-dimensional detection. The commonly used positioning auxiliary modules are generally bright field illumination microscopes. For example, CN118311300A discloses an atomic force microscope; CN1259558C discloses a modular atomic force microscope; and Dimension Icon atomic force microscope produced by Bruker company.

[0005] However, if the bright field microscope wants to position the micro-nano scale surface defects, it needs to increase the magnification of the imaging module, which means reducing the working distance of the positioning microscope, posing a challenge to the design of the AFM system. SUMMARY

[0006] The present application provides a high-sensitivity positioning atomic force microscope detection device and method, which can solve the problem of micro-nano defect positioning and determination of the scanning area to be tested.

[0007] A high-sensitivity positioning atomic force microscope detection device includes a dark-field oblique incidence light source module, an open atomic force scanning module, a microscopic imaging system, and a high-precision motion platform for placing samples.

[0008] The dark field oblique incidence light source module is used for providing a multi-angle oblique incidence light source for the sample, forming a dark field effect, enabling scattered light of micro-nano defects on the sample surface to be captured by the microscopic imaging system, and realizing high-sensitivity positioning.

[0009] The atomic force scanning module comprises a radio frequency modulation laser, a probe assembly and a photodetector.

[0010] The sample is a transparent element, and the incident angle of the dark field oblique incidence light source module illuminating the sample is constrained by the relationship among the numerical aperture of the microscopic imaging system, the refractive index of the sample and the refractive index of the medium. NA The sample center and the edge imaging both satisfy the dark field condition.

[0011] The high-precision motion platform is used for positioning surface defects on the sample in cooperation with the dark field oblique incidence light source module and three-dimensional imaging of the positioned defects in cooperation with the atomic force scanning module.

[0012] The dark field oblique incidence light source module adopts Kohler illumination and comprises an LED, a collimating mirror group and a projection mirror group.

[0013] The light emitted by the LED is uniformly obliquely irradiated to the sample surface after sequentially passing through the collimating mirror group and the projection mirror group, thereby providing a dark field light source for the microscopic imaging system, converting the imaging mode of the microscopic imaging system into a dark field mode for high-sensitivity detection of micro-nano defects, and realizing high-sensitivity positioning.

[0014] The radio frequency modulation laser is used for expanding the spectral width of the laser and reducing the time coherence length by setting the frequency of the radio frequency modulation signal.

[0015] A bias current is superimposed on the radio frequency modulation signal to obtain an injection current. Wherein, f is the frequency of the radio frequency modulation signal, and I is the amplitude of the radio frequency modulation signal.

[0016] The modulation of the current causes the gain coefficient and the refractive index of the gain medium, and further causes amplitude modulation AM and phase modulation PM.

[0017] ;

[0018] Wherein, the modulation depth is​​​​​​ , laser power generated by bias current, amplitude of RF modulated laser power; modulation index , amplitude of angular frequency modulation; using Jacobi-Anger identity and Fourier series expansion:

[0019] ;

[0020] wherein the coefficient , , is the first kind of Bessel function of order n, the intensity of the sideband of order n is:

[0021] ;

[0022] wherein, is the complex amplitude of the sideband of order n;

[0023] RF modulation causes the laser spectrum to produce sidebands, and the spectrum width is broadened;

[0024] By calculating the intensity of different sidebands through the parameters of the RF modulated laser, the coherence length is calculated wherein is a scaling fitting function, is the effective spectrum width; the minimum value between the distance between the cantilever beam on the probe assembly and the sample surface and the sample thickness is set as When , no interference occurs, and the noise signal is suppressed.

[0025] Since the laser irradiates the cantilever beam, the upper surface and the lower surface of the sample at the same time, the scattering signals generated by the surfaces will interfere with the reflection signals of the cantilever beam, affecting the detection results. By reducing the coherence length of the laser, the optical feedback noise and interference signals can be limited.

[0026] Preferably, a filter is mounted in front of the photodetector, which is used to filter out the dark field illumination light and only receive the RF laser.

[0027] Preferably, the atomic force scanning module further comprises a first mirror and a second mirror, and the RF modulated laser output laser sequentially passes through the first mirror, the probe assembly and the second mirror and is reflected into the photodetector. By turning the light path through the mirrors, the RF modulated laser and the photodetector, which are large-volume devices, are moved away from the measurement area, so that the space above the sample to be measured is as open as possible, and the obstruction of the oblique incidence of the dark field light source is reduced, forming an open atomic force scanning module.​​

[0028] Preferably, the high-precision motion platform comprises, from bottom to top, an XY large-range displacement table, an XY plane rotation table and an XYZ three-axis small-range displacement table;

[0029] The XY large-range displacement table is used for full-aperture dark-field high-sensitivity defect positioning of the sample, to determine the position of the defect to be measured on the sample, and to move the defect into the transverse scanning range of the probe assembly.

[0030] The Z-axis of the XYZ three-axis small-range displacement table is used to move the defect to be measured to the longitudinal measurement range of the probe assembly, and the XY axes are used to move the sample to enable scanning of the defect by the probe assembly.

[0031] The XY plane rotation table is used to rotate the sample to a position for imaging of directional defects thereon. Under dark-field oblique incidence illumination, the imaging results of scratches and other directional structures are affected by the illumination azimuth angle. Since the probe assembly, mirrors, mechanical parts and other components block the light, the dark-field oblique incidence light source module cannot provide illumination covering 360° azimuth angle. By rotating the sample, 360° azimuth angle illumination for directional defects on the sample is compensated for, and the missed detection due to directionality is eliminated.

[0032] Further, during rotation of the sample by the XY plane rotation table, the XY coordinates of the rotation center are set as , the coordinates of the defect to be measured are , the sample is rotated counterclockwise by an angle of θ , and the coordinates after rotation are calculated by the following formula:

[0033]

[0034] By compensating for the distances and by the XY large-range displacement table, the illumination results of the defect to be measured on the surface of the sample in the same field of view of the microscopic imaging system at different defect angles are obtained, and missed detection is rejected.

[0035] Further, when the sample is a transparent element, scattered light generated by the high-precision motion platform on which the sample is placed can enter the microscopic imaging system, thereby destroying the dark-field imaging condition. To increase the versatility of the equipment and cover transparent element detection, an ultrasmooth high-reflection surface or a black body material is placed as an intermediate layer between the XYZ three-axis small-range displacement table and the sample, to prevent scattered light from the surface of the displacement table from destroying the dark-field condition.

[0036] Further, the relationship between the incident angle of the dark-field oblique incidence light source module to the sample , the refractive index of the sample , and the numerical aperture of the microscopic imaging system is constrained, and specifically as follows:​

[0037] ;

[0038] ;

[0039] In the formula, is the incident angle is the corresponding refraction angle; the reflected light from the sample back and the intermediate layer surface is reflected, and the incident angle of the reflected light to the sample sidewall is , the corresponding refraction angle is ;

[0040] Need to meet Or ; if , the imaging near the sample edge still meets the dark field condition; if , total reflection occurs at the sample edge, and the angle is , still meet the dark field condition.

[0041] A high-sensitivity positioning atomic force microscope detection method adopts the atomic force microscope detection device, and comprises the following steps:

[0042] S1, using a horizontal placement posture, fixing the sample to be measured on a high-precision motion platform; an ultra-smooth high-reflective surface or a black body material is placed between the sample and the high-precision motion platform;

[0043] S2, using the XY large-range displacement table in the high-precision motion platform to perform full-aperture micro-nano defect high-sensitivity positioning on the sample, moving the defect to be measured on the sample to the lateral scanning range of the probe assembly; if the defect has directionality, the XY large-range displacement table and the XY plane rotation table in the high-precision motion platform are operated to rotate and translate the defect to the best imaging position;

[0044] S3, operating the XYZ three-axis small-range displacement table in the high-precision motion platform, moving the defect to be measured on the sample to the measurement range of the probe assembly;

[0045] S4, using the atomic force scanning module to measure, obtaining the three-dimensional morphology of the defect to be measured.

[0046] Compared with the prior art, the present application has the following beneficial effects:

[0047] 1、The present application provides a multi-angle oblique incident light source for the sample by setting a dark field oblique incident light source module, and designs an open atomic force scanning module, which combines the dark field high-sensitivity positioning and AFM high-precision detection capability, realizes cross-scale nano-level microstructure positioning and three-dimensional morphology imaging.

[0048] 2. The application designs a radio frequency modulation laser, selects a proper radio frequency signal frequency according to theoretical derivation and probe working distance.

[0049] 3. The application considers part shielding, and combines a displacement table and a rotating table to realize all-around defect detection without missing.

[0050] 4. The application expands the detection capability of the transparent element, analyzes and derives edge scattering influence, and expands the dark field detection area. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 It is a schematic diagram of the overall structure of the high-sensitivity positioning atomic force microscope detection device of the application.

[0052] Figure 2 It is a schematic diagram of the structure in the top view.

[0053] Figure 3 It is a schematic diagram of the high-precision motion platform in the application.

[0054] Figure 4 It is a schematic diagram of the rotating positioning coordinates in the application.

[0055] Figure 5 It is a schematic diagram of the transparent element edge detection in the application.

[0056] Figure 6 It is a test result diagram of the application. DETAILED DESCRIPTION

[0057] The application will be further described in detail below in combination with the drawings and embodiments, and it should be pointed out that the following embodiments are intended to facilitate the understanding of the application and do not limit the application in any way.

[0058] As shown in Figure 1 and Figure 2 , a high-sensitivity positioning atomic force microscope detection device includes an open atomic force scanning module, a dark field oblique incidence light source module 5, a microscopic imaging system 7, and a high-precision motion platform 9 for placing a sample 8.

[0059] The atomic force scanning module includes a radio frequency modulation laser 1, a first mirror 21, a probe assembly 6, a second mirror 22, and a photodetector 3. The radio frequency modulation laser 1 outputs laser light that sequentially passes through the first mirror 21, the probe assembly 6, and the second mirror 22 and is reflected into the photodetector 3.

[0060] A filter is installed in front of the photodetector 3 to eliminate the influence of the dark field oblique incidence light. The radio frequency modulation laser 1 sets the frequency of the radio frequency modulation signal to widen the spectral width of the laser light and reduce the time coherence length.

[0061] Since the laser irradiates the cantilever beam of the probe assembly 6, the upper surface and the lower surface of the sample are also irradiated, the scattering signals generated by the surfaces interfere with the reflection signals of the cantilever beam, and the detection result is affected. By reducing the coherence length of the laser, the optical feedback noise and the interference signals can be reduced.

[0062] The frequency selection method of the radio frequency modulation signal is as follows:

[0063] The bias current is superimposed on the radio frequency modulation signal , to obtain the injection current ; wherein, , is the frequency of the radio frequency modulation signal, is the amplitude of the radio frequency modulation signal;

[0064] The modulation of the current causes the gain coefficient and the refractive index of the gain medium, and further causes amplitude modulation AM and phase modulation PM. The expression of the light field after modulation is:

[0065] ;

[0066] wherein, the modulation depth , is the laser power generated by the bias current, is the amplitude of the laser power of the radio frequency modulation; the modulation index , is the amplitude of the angular frequency modulation; by using Jacobi-Anger identity and Fourier series expansion, it is obtained that:

[0067] ;

[0068] wherein, the coefficient , , is the first kind of Bessel function of order , and the intensity of the sideband of order

[0069] ;

[0070] wherein, is the complex amplitude of the sideband of order ;

[0071] The radio frequency modulation causes the laser spectrum to generate sidebands, and the spectrum width is widened;

[0072] By calculating the different sideband intensities by the parameters of the radio frequency modulation laser, the coherence length is obtained, wherein is a scaling fitting function, To determine the effective spectral width; the minimum value between the distance between the cantilever beam on the probe assembly and the sample surface, and the sample thickness, is set to [value missing]. ,when When this happens, no interference occurs, thus suppressing the noise signal.

[0073] When the probe assembly 6 scans, the probe interacts with the surface of the sample 8, causing the cantilever to deflect, thus changing the laser light reflected onto the photodetector 3. The optical path is deflected by the first reflector 21 and the second reflector 22, keeping the large-volume devices such as the RF modulated laser 1 and the photodetector 3 away from the measurement area, making the area above the sample 8 as open as possible and reducing obstructions when the dark-field oblique incidence light source module 5 is obliquely incident. Precision manual adjustment frames 41 and 12 can adjust the position of the RF modulated laser 1, and precision manual adjustment frames 42 and 14 can adjust the position of the photodetector 3, thereby accurately acquiring the feedback signal from the cantilever beam. The precision manual adjustment frame 10 can be used to test samples 8 of different thicknesses.

[0074] The microscopic imaging system 7 includes an imaging lens assembly and an imaging CCD / CMOS component. The dark-field oblique incidence light source module 5 includes an LED, a collimation module, and a projection module. The light from the LED is first collimated and then projected, so that the light is uniformly illuminated on the surface of the sample 8. The divergence angle is small, and reflected light will not enter the microscopic imaging system 7. Only the scattered light from defects is captured, thereby improving the defect detection sensitivity. The optical lens assembly is miniaturized through special customization to reduce interference with the atomic force scanning head module and provide illumination from as many directions as possible.

[0075] like Figure 3 As shown, the high-precision motion platform 9 consists of a three-axis small-range displacement stage 91 (XYZ axis), a large-range displacement stage 93 (XY axis), and a rotary stage 92 (XY plane). The three-axis small-range displacement stage 91 (XYZ axis) is used for ultra-high precision AFM detection, and the probe assembly 6 scans defects by moving the sample 8; the Z-axis is used to adjust the sample to move the defect to be tested into the longitudinal measurement range of the probe assembly 6. The large-range displacement stage 93 (XY axis) works in conjunction with a dark field to scan the full caliber of the sample 8 to locate the defect to be tested and move it below the probe assembly 6. The entire system is placed on a vibration isolation platform 11 to ensure the detection accuracy of AFM.

[0076] Under dark-field oblique incidence illumination, the imaging results of directional structures such as scratches are affected by the illumination azimuth angle. For example... Figure 2 As shown, due to the obstruction of components such as probe assembly 6, reflector 2, and mechanical parts, the dark field oblique incidence light source module 5 cannot provide 360° azimuth illumination coverage and needs to be used in conjunction with XY plane rotary stage 92 to achieve full-angle coverage.

[0077] like Figure 4 As shown, the XY coordinates of the rotation center are set as follows: , the coordinates of the current defect to be measured are , the sample is rotated counterclockwise by an angle θ , the coordinates after rotation are which can be calculated by the following formula:

[0078] ;

[0079] Compensate the distance by the XY large-range displacement table 93 and The same field of view can be achieved in the different angle illumination results of the defect to be measured, and the missed detection is eliminated.

[0080] When the measurement object is a transparent element, the scattered light generated by the sample table fixing the sample can enter the microscopic imaging system, thereby destroying the dark field condition. In order to increase the universality of the equipment and cover the detection of transparent elements, an intermediate layer 13 of ultra-smooth high-reflective surface or black body material needs to be placed between the sample 8 and the XYZ three-axis small-range displacement table 91. As shown in Figure 5 , the influence of the sample edge needs to be considered, in order to reduce the influence of the sample edge and expand the dark field detection range, the relationship between the incident angle of the dark field oblique incidence light source module, the material of the sample to be measured , and the numerical aperture of the high-power microscopic imaging system needs to be constrained:

[0081] According to the refraction law, the relationship between the incident angle and the refraction angle is

[0082] ;

[0083] The refracted light hits the high-reflective surface and is reflected, if the reflected light hits the sample side wall, the angle is , and the refracted light (the angle is ) may enter the high-power microscopic imaging system, thereby destroying the dark field condition:

[0084] ;

[0085] Satisfy the above two formulas:

[0086] ;

[0087] Need to satisfy or ; if , the imaging near the sample edge still satisfies the dark field condition, the imaging result has high contrast, and the detection range on the transparent sample is expanded. If , total reflection occurs at the sample edge, exits on the upper surface of the sample, and the angle is , still satisfying the dark field condition.

[0088] As Figure 6 shown, to prove the detection sensitivity is improved, install coaxial illumination light source on the microscopic imaging system 7, can compare the bright field and dark field imaging results in the same field of view. In the figure, the upper left diagram shows the device bright field microscopic imaging, no defect; the upper right diagram shows the device dark field microscopic imaging, with defects; the lower left diagram shows the device AFM detection result, the lower right diagram corresponds to the cross-sectional distribution of the AFM measurement result, the defect is about 0.7 μm wide and about 2 nm deep. It can be seen that the present application has the ability of dark field nanoscale high sensitivity positioning and AFM high precision detection.

[0089] The above-described embodiments detail the technical solutions and beneficial effects of the present application, and it should be understood that the above-described is only a specific embodiment of the present application and is not intended to limit the present application, and any modification, supplement and equivalent replacement made within the principle range of the present application should be included in the protection scope of the present application.

Claims

1. A high-sensitivity positioning atomic force microscope detection device, characterized by, The dark field oblique incidence light source module (5), the open atomic force scanning module, the microscopic imaging system (7) and the high-precision motion platform (9) for placing the sample (8) are included; The dark field oblique incidence light source module (5) is used for providing multi-angle oblique incidence light sources for the sample (8), forming a dark field effect, so that the scattered light of the micro-nano defect on the surface of the sample (8) is captured by the microscopic imaging system (7), and high-sensitivity positioning is realized. The atomic force scanning module includes a radio frequency modulation laser (1), a probe assembly (6) and a photoelectric detector (3); the radio frequency modulation laser (1) outputs laser which is reflected to the photoelectric detector (3) after irradiating on the probe assembly (6); The sample (8) is a transparent element, and the incident angle of the dark field oblique incident light source module (5) illuminating the sample (8) is constrained by the relationship of The refractive index of the sample The numerical aperture of the microscopic imaging system (7) NA The center and the edge of the sample (8) are imaged to meet the dark field condition, and the specific implementation is as follows: ； ； In the formula, incident angle corresponding angle of refraction; the reflected light hits the sample back and the intermediate layer surface, and the incident angle of the reflected light hitting the sample side wall is corresponding angle of refraction ; Must satisfy Or If Then imaging near the edge of the sample still satisfies the dark-field condition; if Then total internal reflection occurs at the edge of the sample, exits the upper surface of the sample, and the angle is Still satisfies the dark-field condition; The high-precision motion platform (9) is used for positioning the surface defect on the sample (8) in cooperation with the dark field oblique incidence light source module (5), and three-dimensional imaging of the positioned defect in cooperation with the atomic force scanning module.

2. The high-sensitivity positioned atomic force microscope detection device according to claim 1, characterized in that The dark field oblique incidence light source module (5) adopts Kohler illumination and includes an LED, a collimating mirror group and a projection mirror group; After the light emitted by the LED sequentially passes through the collimating mirror group and the projection mirror group, the light is uniformly obliquely irradiated to the surface of the sample (8), thereby providing a dark field light source for the microscopic imaging system (7), so that the imaging mode of the microscopic imaging system (7) is converted into a dark field mode for high-sensitivity detection of the micro-nano defect, and high-sensitivity positioning is realized; the dark field oblique incidence light source module (5) is arranged above the open atomic force scanning module to provide multiple oblique incidence light sources, so that the dark field light source provides multi-angle illumination, and the missing detection of defects with directionality is reduced.

3. The high-sensitivity positioned atomic force microscope detection device according to claim 1, wherein The frequency of the radio frequency modulation signal is set to widen the spectral width of the laser and reduce the time coherence length; the frequency selection method of the radio frequency modulation signal is as follows: Superimposing a bias current on a radio frequency modulated signal , resulting in an injection current ; wherein , is the frequency of the radio frequency modulated signal, is the amplitude of the radio frequency modulated signal; The modulation of the current causes the gain coefficient and the refractive index of the gain medium, and then causes amplitude modulation AM and phase modulation PM; the expression of the light field after modulation is as follows: ； where the modulation depth , is the laser power generated by the bias current, is the amplitude of the RF modulated laser power; the modulation index , is the amplitude of the angular frequency modulation; using the Jacobi-Anger identity and the Fourier series expansion: ； Among them, coefficient , , yes The first-order Bessel function of the first kind, the second-order Bessel function of the first kind, the third-order Bessel function The strength of the stepped edge band is: ； wherein is the complex amplitude of the mth order sideband; The radio frequency modulation causes sidebands of the laser spectrum, and the spectral width is widened; By modulating the parameters of the laser with radio frequency, the different sideband intensities are calculated, and then the coherence length is calculated wherein is a scaling fit function, is the effective spectral width; the minimum value between the distance of the cantilever on the probe assembly and the sample surface and the sample thickness is set as When , no interference occurs, and the noise signal is suppressed.

4. The high-sensitivity positioned atomic force microscope detection device according to claim 1, wherein The photoelectric detector (3) is provided with a filter in front, which is used for filtering out the dark field illumination light and only receiving the radio frequency laser.

5. The high-sensitivity positioned atomic force microscope detection device of claim 1, wherein, The atomic force scanning module further includes a first reflector and a second reflector; the laser output by the radio frequency modulation laser (1) sequentially passes through the first reflector, the probe assembly (6) and the second reflector, and is then reflected to the photoelectric detector (3).

6. The high-sensitivity positioned atomic force microscope detection device of claim 1, wherein, The high-precision motion platform (9) includes an XY large-range displacement table (93), an XY plane rotation table (92) and an XYZ three-axis small-range displacement table (91) arranged from bottom to top; The XY large-range displacement table (93) is used for full-aperture dark field high-sensitivity defect positioning of the sample (8), and determining the position of the defect to be measured on the sample (8) so as to move the defect into the transverse scanning range of the probe assembly (6); The Z axis of the XYZ three-axis small-range displacement table (91) is used for moving the defect to be measured to the longitudinal measurement range of the probe assembly (6), and the XY axis is used for moving the sample (8) to realize scanning of the defect by the probe assembly (6). The XY plane rotation table (92) is used to rotate the sample (8) to the position for imaging the directional defects; by rotating the sample, the 360° azimuthal illumination for the directional defects on the sample (8) is compensated, and the missing detection due to the directionality is eliminated.

7. The high-sensitivity positioned atomic force microscope detection device according to claim 6, characterized in that During rotation of the sample (8) by the XY plane rotation stage (92), the XY coordinates of the rotation center are set as , the coordinates of the current defect to be measured are , and the sample (8) is rotated counterclockwise by an angle of θ , the coordinates after rotation are calculated as follows: ； Compensate distance by XY large range displacement stage (93) and Obtain the illumination results of the defects on the surface of the sample (8) in the same field of view of the microscopic imaging system (7) at different defect angles.

8. The high-sensitivity positioned atomic force microscope detection device of claim 6, wherein, An ultra-smooth high-reflection surface or black body material is placed between the XYZ three-axis small-range displacement table (91) and the sample (8) as an intermediate layer, which is used to prevent the scattered light from the surface of the displacement table from destroying the dark field condition.

9. A high-sensitivity positioning atomic force microscope detection method, characterized in that, The atomic force microscope detection device according to any one of claims 1-8, The method comprises the following steps: S1, in a horizontal placement posture, fixing the sample to be detected on a high-precision motion platform; an ultra-smooth high-reflection surface or black body material is placed between the sample and the high-precision motion platform; S2, using the XY large-range displacement table in the high-precision motion platform to position the sample with high sensitivity, moving the defect to be detected on the sample to the lateral scanning range of the probe assembly; If the defect has directionality, the XY large-range displacement table and the XY plane rotation table in the high-precision motion platform are operated to rotate and translate the defect to the best imaging position; S3, operating the XYZ three-axis small-range displacement table in the high-precision motion platform to move the defect to be detected on the sample to the measurement range of the probe assembly; S4, using the atomic force scanning module to measure and obtain the three-dimensional morphology of the defect to be detected.

Images