Hydrophobic micro-nano flexible film structure and characterization method

Abstract

The invention discloses a hydrophobic micro-nano flexible thin film structure and a characterization method, relates to the technical field of thin film structure characterization, and aims to solve the problems of poor supporting performance of a flexible thin film and inaccurate standard data acquisition. Different acceleration voltages and currents are set for the coarse thinning stage and the fine thinning stage, fine removal of materials can be achieved, the accuracy of the thinning thickness is guaranteed, the thickness, the surface fluctuation amplitude and the microstructure feature size of a thin film in a measured image are measured with the help of a scale tool, and the measurement accuracy is improved. The morphological characteristics of the hydrophobic micro-nano flexible film can be converted into accurate data, rigid support is provided for the film by utilizing high hardness, high chemical stability and good thermal conductivity of tungsten, the upper side and the lower side of a target area are milled, hole digging is conducted on surrounding materials to form a preliminary sheet contour, then U-shaped milling and back-splashing material cleaning are conducted, and the thin film is obtained. The sample form is effectively controlled, and damage of processing stress to the sample structure is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of thin film structure characterization, in particular to a hydrophobic micro-nanoscale flexible thin film structure and a characterization method. Background Art

[0002] Flexible films have important applications in consumer electronics, automotive electronics, medical devices, smart textiles, aerospace, flexible solar cells, flexible sensors, flexible batteries and other fields.

[0003] Chinese patent publication number CN116432431A discloses a method for modeling and simulating the surface morphology fractal growth of nanosilver flexible films. This method primarily simulates and emulates the fractal growth of nanosilver flexible films under different preparation process parameters by changing model parameters. The model simulation results guide experimental research on the preparation of nanometal flexible films, accelerate the optimization of the preparation process, and thus improve laboratory research efficiency. Computer simulations can be run to quickly simulate the surface morphology of nanosilver flexible films prepared using an in-situ reduction method. While this patent addresses the issue of obtaining film characterization data, the following issues remain in actual operation: 1. Directly vaporizing the surface of the flexible film with gold causes gold particles to be embedded in the surface of the flexible film, thereby destroying the surface morphology of the flexible film.

[0004] 2. The flexible film is not processed and protected in a targeted manner, which makes the film surface easily deformed.

[0005] 3. There is no targeted thickness removal of the flexible film, and no effective measurement of the final flexible film, resulting in inaccurate final film data acquisition. Summary of the Invention

[0006] The purpose of the present invention is to provide a hydrophobic micro-nanoscale flexible film structure and characterization method. Different acceleration voltages and currents are set for the coarse thinning and fine thinning stages to achieve fine material removal and ensure the accuracy of the thinning thickness. The thickness, surface undulation amplitude and microstructure feature size of the film in the measurement image are measured with the help of a ruler tool, and the morphological characteristics of the hydrophobic micro-nanoscale flexible film can be converted into precise data. The high hardness, high chemical stability and good thermal conductivity of tungsten are utilized to provide rigid support for the film. The upper and lower sides of the target area are first milled and the surrounding material is dug to form a preliminary thin film outline. Then U-shaped milling and backsplash material cleaning are performed to effectively control the sample morphology and reduce the damage to the sample structure caused by processing stress, which can solve the problems in the prior art.

[0007] To achieve the above object, the present invention provides the following technical solutions: A hydrophobic micro-nanoscale flexible film structure, comprising a flexible film body structure, a surface protection structure, a conductive structure, a support structure, and a fixing structure; The surface protection structure is a light stroke on the film surface with an oil-based marker, which forms a dot-shaped ink distribution due to its hydrophobicity, used to mark the sampling area and protect the surface; the conductive structure is a gold vaporization layer; the supporting structure includes an upper protection layer, a sample layer and a lower protection layer; and the fixed structure is a copper grid substrate.

[0008] Characterization methods for hydrophobic micro- and nano-scale flexible film structures, including: First, the film sample is pretreated, the target area of ​​the pretreated sample is marked, and the marked target area is preliminarily protected. The sample that has completed the preliminarily protection is rough-processed. After the rough processing is completed, the sample is separated, and the separated sample is secondary protected. The sample after secondary protection is thinned and sampled. After thinning and sampling, microstructure imaging is completed under low-damage conditions to obtain film size and morphology data.

[0009] Preferably, the film sample is subjected to sample pretreatment, comprising: Use an oil-based marker to draw a line on the surface of the hydrophobic film. After the line is drawn, the surface of the film is distributed in a dotted pattern and a surface protection structure is formed. Let the film surface stand until the pen oil dries; The dried film sample is placed in a gold evaporation device, and a layer of gold film is evaporated on the surface of the film sample; Finally, the sample pretreatment of the film sample is completed.

[0010] Preferably, the target area of ​​the pretreated sample is marked, and the marked target area is initially protected, including: The pretreated thin film sample is placed in the sample chamber of a focused ion beam electron beam dual beam electron microscope, and the electron beam is used to scan the sample surface at a low magnification; According to the scanning results, the traces of point distribution on the sample surface are identified; The identified point-like distribution area is used as the target area, and the boundary of the target area is marked using the marking function of the focused ion beam electron beam dual beam electron microscope; Then, the target area is preliminarily protected by adjusting the ion beam angle of the focused ion beam electron beam dual-beam electron microscope, wherein the ion beam angle is 52°, the acceleration voltage is set to 30 kV, and the ion beam current is set to 0.23 nA; Deposit a tungsten protective layer on the surface of the target area with a thickness of 1 μm; The deposition process is started, and the tungsten material covers the target area under the action of the ion beam, forming the preliminary structure of the upper protective layer and the sample layer.

[0011] Preferably, identifying the traces of point distribution on the sample surface according to the scanning results includes: Preprocessing the electron microscopic image obtained by scanning the sample surface to obtain a preprocessed electron microscopic image; wherein the preprocessing includes grayscale normalization processing and noise suppression processing; Retrieve the global grayscale average and grayscale standard deviation of the preprocessed electron microscopy image; Setting a dynamic threshold using the global grayscale average and grayscale standard deviation of the preprocessed electron microscopy image; The pixels contained in the sub-microscopic image are compared with the dynamic threshold respectively, and the pixels whose grayscale values ​​exceed the dynamic threshold are screened out as candidate pixels; Perform resonance scoring processing on the candidate pixel points to obtain the resonance score value corresponding to each candidate pixel point; Comparing the resonance score value with a preset score threshold, wherein the preset score threshold is in the range of 0.62-0.67; The candidate pixel points whose resonance score value exceeds the preset score threshold are taken as target pixel points; For the target pixel point, the resonance score value and pixel confidence are used to generate the trace possibility evaluation index corresponding to each target pixel point; The trace possibility evaluation index corresponding to the target pixel is compared with a preset index threshold; wherein the preset index threshold value range is 0.42-0.51; The target pixel points whose trace possibility evaluation index is not lower than a preset index threshold are taken as trace effective pixel points, and the trace effective pixel points are integrated to form a point distribution area.

[0012] Preferably, performing resonance scoring processing on the candidate pixels to obtain a resonance score value corresponding to each candidate pixel includes: Performing multi-scale feature extraction on the pre-processed electron microscopy image to obtain multi-scale features; wherein the multi-scale features include spatial scale features, material intrinsic features, geometric topology features, and dynamic process features; Extracting local features of each candidate pixel, wherein the local features of the candidate pixel include grayscale distribution, texture pattern and physical field parameters; Determine the cosine similarity S(x, y) between the feature vector formed by the local feature of each candidate pixel and the feature vector formed by the multi-scale feature; Calculation of phase gradient Φ for electron microscopy images BSE ; Establishing a topological network on the candidate pixel points, and calculating a topological continuity score for each candidate pixel point based on the topological network; The resonance score value corresponding to the candidate pixel point (x, y) is obtained by utilizing the topological continuity score of each candidate pixel point in combination with the geometric constraint factor of each candidate pixel point.

[0013] Preferably, the sample after the preliminary protection is subjected to rough processing, and after the rough processing is completed, the sample is separated, including: Before rough machining, the parameters of the focused ion beam electron beam dual beam electron microscope were set. The ion beam angle of the focused ion beam electron beam dual beam electron microscope was adjusted to 52°, the acceleration voltage was 30kV, and the ion beam current was increased to 9.3nA. Centering the sample that has been preliminarily protected, the ion beam is used to mill the upper and lower sides of the target area, hollowing out the surrounding material of the target area to form a preliminary thin slice outline. After forming the preliminary thin slice outline, the ion beam angle was changed to 0°, the voltage was maintained at 30 kV, the current was reduced to 2.5 nA, and U-shaped milling was performed on the bottom and sides of the target area; After U-shaped milling, the ion beam angle was restored to 52°, the voltage was 30 kV, and the current was 2.5 nA to clean the backsplash material generated during the U-shaped milling process; After cleaning, the rough processing of the sample is completed, and the sample after rough processing is separated: For sample separation, the focused ion beam electron microscope was first switched to low current mode, with an ion beam angle of 0° and a voltage of 30 kV. The micromanipulator was lowered above the target area of ​​the rough-machined sample, and the tip of the micromanipulator was brought into contact with the surface of the target area. The micromanipulator was then fixed to the target area by ion beam-induced carbon deposition. After adhesion, lift the micro-manipulator upwards, detach it from the substrate, and rotate it 180°. Point the tip of the micro-manipulator downwards, with the bottom of the target area facing upwards. Place the rotated sample tip in contact with the sample stage, connect the sample and the sample stage with carbon, and cut off the connection between the micro-manipulator and the sample. The sample stage is rotated 180° again, so that the bottom of the target area is facing upwards. The micro-manipulation needle is lowered again to contact the target area. After connecting with carbon, the connection between the sample and the sample stage is cut off. The sample is extracted again onto the micro-manipulation needle, and the needle is rotated 180° again to restore the normal orientation of the sample. Finally, the micromanipulator is moved to the top of the copper grid and adjusted so that the target area is aligned with the copper grid. The sample is bonded to the side of the copper grid with carbon. The connection between the sample and the micromanipulator is then severed with an ion beam. The needle is then removed to complete the fixation of the sample on the copper grid. Finally, the sample separation is completed.

[0014] Preferably, the separated sample is subjected to secondary protection, including: The ion beam angle of the focused ion beam electron beam dual-beam electron microscope was adjusted to 0°, the acceleration voltage was set to 30 kV, and the ion beam current was reduced to 80 pA; Start the ion beam induced deposition process to deposit a 1 μm thick protective layer of tungsten on the lower surface of the sample fixed on the copper grid; During the deposition process, the ion beam continuously scans the bottom of the sample, evenly covering the tungsten material to form a continuous tungsten layer; After the deposition is completed, switch to electron beam mode to observe the sample cross-section to confirm that the upper protective layer, sample layer, and lower protective layer form a complete three-layer structure. The upper protective layer is the tungsten layer deposited during the initial protection, and the lower protective layer is the tungsten layer deposited during the secondary protection. Finally, the secondary protection of the sample is completed.

[0015] Preferably, the sample after secondary protection is thinned and sampled, comprising: Confirm the thinning area of ​​the sample after secondary protection; After the thinning area was confirmed, the parameters of the focused ion beam electron beam dual-beam electron microscope were adjusted. The ion beam angle was set to 52°, and the acceleration voltage was divided into a rough thinning stage and a fine thinning stage. The current in the rough thinning stage was set to 0.43nA, and the current in the fine thinning stage was reduced to 80pA. The thinning area is first subjected to rough thinning. Rough thinning is performed by milling the thinning area at a 52° ion beam angle and a 0.43nA current, removing material layer by layer from the upper protective layer to the bottom until the remaining thickness is 100nm. When the milling time reaches the preset time, the SEM mode is switched to scan and the remaining thickness is measured. The thinned area is then fine-thinned by reducing the ion beam current to 80 pA and milling the thinned area. The thickness of the sample is measured after each milling until the sample thickness reaches 50 nm. After the sample is thinned, the sample surface is scanned with an ion beam. If local thickness unevenness is found after scanning, the thick area is locally refined using a current of 80 pA. Then, the surface of the sample fixed on the copper grid and thinned is cleaned; Finally, the sample thinning and preparation is completed.

[0016] Preferably, after thinning and preparing the sample, microstructure imaging is performed under low damage conditions to obtain film size and morphology data, including: The thinned sample is loaded into the sample holder of the focused ion beam electron beam dual beam electron microscope; In a focused ion beam electron beam dual beam electron microscope, the edge of the copper grid or a non-target area is first selected as the focus point, and the sample is coarsely focused at low magnification. At the same time, the electron beam avoids the target area of ​​the sample during the focusing process. Then, use low-magnification scanning to find the target area of ​​the sample on the copper grid. At the same time, magnify it to 10,000× and confirm the sample position. Perform fine focusing in a blank area away from the sample target area. After focusing is completed, the sample stage is quickly moved to translate the sample target area to the center of the field of view. After the sample is translated, a high-sensitivity CCD camera is used to expose the sample. If multiple areas are to be observed, the field of view is quickly switched in sequence, and each area is photographed no more than twice to obtain the measured image. Use the ruler tool to measure the thickness, surface undulation amplitude and microstructure feature size of the film in the measurement image; The final measurement data are the characterization data of the hydrophobic micro-nanoscale flexible film.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. The hydrophobic micro-nanoscale flexible thin film structure and characterization method provided by the present invention can significantly improve the conductive properties of the thin film sample by evaporating a layer of gold film on the surface of the thin film sample, avoiding the impact of charge accumulation on imaging quality during electron microscopy and other detection processes. The gold film coverage provides an additional protective barrier for the thin film sample, further preventing the sample from being oxidized or contaminated, and extending the sample's shelf life.

[0018] 2. The hydrophobic micro-nanoscale flexible film structure and characterization method provided by the present invention first mills the upper and lower sides of the target area and digs the surrounding material to form a preliminary thin film outline, and then performs U-shaped milling and backsplash material cleaning. This step-by-step processing method can effectively control the sample morphology and reduce the damage to the sample structure caused by processing stress. It utilizes the high hardness, high chemical stability and good thermal conductivity of tungsten to provide rigid support for the film.

[0019] 3. The hydrophobic micro-nanoscale flexible film structure and characterization method provided by the present invention adopts an operational process of coarse thinning followed by fine thinning, making the sample preparation process more orderly and controllable. Different acceleration voltages and currents are set for the coarse thinning and fine thinning stages to achieve fine material removal and ensure the accuracy of the thinning thickness. With the help of a ruler tool, the thickness, surface undulation amplitude and microstructure feature size of the film in the measurement image can be measured, and the morphological characteristics of the hydrophobic micro-nanoscale flexible film can be converted into precise data. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the characterization steps of the hydrophobic micro-nanoscale flexible film of the present invention. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0022] In order to solve the problem in the prior art that the surface of the flexible film is directly subjected to gold vaporization treatment, thereby causing gold particles to be embedded in the surface of the flexible film and destroying the surface morphology of the flexible film, please refer to Figure 1 , this embodiment provides the following technical solutions: A hydrophobic micro-nanoscale flexible film structure, comprising a flexible film body structure, a surface protection structure, a conductive structure, a support structure, and a fixing structure; The surface protection structure is a light stroke on the film surface with an oil-based marker, which forms a dot-shaped ink distribution due to its hydrophobicity, used to mark the sampling area and protect the surface; the conductive structure is a gold vaporization layer; the supporting structure includes an upper protection layer, a sample layer and a lower protection layer; and the fixed structure is a copper grid substrate.

[0023] Specifically, the surface protection structure uses hydrophobicity to make the oil-based marker form a dot-shaped ink distribution, which can not only accurately mark the sampling area and avoid scratches and contamination of the film surface by traditional marking methods, but also rely on the hydrophobic property to isolate external water vapor, dust and other impurities, and prevent the film surface from changing its performance due to the adsorption of foreign matter, effectively improving the durability and surface cleanliness of the film in complex environments, and providing reliable original conditions for subsequent sample analysis and experimental operations. The evaporated gold layer serves as a conductive structure. The gold material has excellent conductivity, chemical stability and oxidation resistance, and can ensure efficient and stable current transmission at the micro-nano scale, reducing resistance loss and signal attenuation. The support structure consists of an upper protective layer, a sample layer and a lower protective layer. The three-layer structure works synergistically to provide good mechanical support and buffer protection for the film. The copper grid base serves as a fixed structure with good mechanical strength and processing performance, which is convenient for connection and fixation with other equipment or carriers.

[0024] Characterization methods for hydrophobic micro- and nano-scale flexible film structures, including: First, the film sample is pretreated, the target area of ​​the pretreated sample is marked, and the marked target area is preliminarily protected. The sample that has completed the preliminarily protection is rough-processed. After the rough processing is completed, the sample is separated, and the separated sample is secondary protected. The sample after secondary protection is thinned and sampled. After thinning and sampling, microstructure imaging is completed under low-damage conditions to obtain film size and morphology data.

[0025] Specifically, marking and initial protection of target areas can precisely target hydrophobic functional areas or specific micro-nanostructure sites on the film surface, avoiding information redundancy caused by global processing. The dual protection mechanism (primary protection and secondary protection) and low-damage sample preparation process can effectively address the deformation and damage characteristics of flexible films. During rough processing and separation, primary protection prevents mechanical forces from pulling and damaging the film microstructure. Secondary protection combined with low-damage treatment during thinning and sample preparation (such as ion beam thinning or vibration polishing) can avoid the damage to hydrophobic interfaces or flexible substrates caused by high temperatures and high pressures in traditional sample preparation. Full process control from pretreatment to low-damage imaging can minimize artifacts introduced by sample preparation. Pretreatment removes surface contaminants (such as residual solvents and dust) to avoid interference of impurities in morphological observation; thinning the sample to make the film reach the observation thickness requirements of high-precision equipment such as transmission electron microscopy (usually <100nm), ensuring that the three-dimensional information of the micro-nanostructure can be accurately restored through two-dimensional imaging; low-damage imaging (such as using low-voltage scanning electron microscopy or cryo-electron microscopy technology) can avoid the collapse of the film structure or changes in chemical composition caused by electron beam irradiation, so that the obtained dimensions (such as nanocolumn height, pore diameter) and morphological data (such as surface roughness, structural periodicity) are closer to the actual state of the sample.

[0026] The film samples were subjected to sample pretreatment, including: Use an oil-based marker to draw a line on the surface of the hydrophobic film. After the line is drawn, the surface of the film is distributed in a dotted pattern and a surface protection structure is formed. Let the film surface stand until the pen oil dries; The dried film sample is placed in a gold evaporation device, and a layer of gold film is evaporated on the surface of the film sample; Finally, the sample pretreatment of the film sample is completed.

[0027] Specifically, an oil-based marker is used to draw a line on the surface of the hydrophobic film to form a dot distribution and surface protection structure. This operation is simple and efficient. The dot distribution structure can increase the roughness of the film surface, change its surface properties, make the film easier to interact with other substances in the subsequent experimental process, and improve the sensitivity and stability of the detection signal. At the same time, the surface protection structure formed can, to a certain extent, prevent the film surface from being physically damaged in subsequent operations, protect the original properties of the film sample, and ensure the reliability of the experimental results. The film surface is left to stand until the pen oil dries, ensuring that the oily substance will not interfere with the subsequent gold film evaporation step, and preventing the problem of uneven gold film evaporation or failure to adhere due to residual oily substances. Only after the pen oil is completely dried, the physical and chemical properties of the film surface are in a stable state, providing good base conditions for evaporating the gold film. Evaporating a layer of gold film on the surface of the film sample has many advantages. Gold has good conductivity and chemical stability, which can significantly improve the conductive properties of the film sample and avoid the impact of charge accumulation on imaging quality during electron microscopy and other detection processes. The gold coating provides an additional protective barrier for thin-film samples, further preventing oxidation and contamination, and extending their shelf life. Furthermore, the presence of the gold coating enhances the reflectivity of the thin-film sample surface, improving accuracy and clarity in optical testing and other experiments.

[0028] Mark the target area of ​​the pretreated sample and perform preliminary protection on the marked target area, including: The pretreated thin film sample is placed in the sample chamber of a focused ion beam electron beam dual beam electron microscope, and the electron beam is used to scan the sample surface at a low magnification; According to the scanning results, the traces of point distribution on the sample surface are identified; The identified point-like distribution area is used as the target area, and the boundary of the target area is marked using the marking function of the focused ion beam electron beam dual beam electron microscope; Then, the target area is preliminarily protected by adjusting the ion beam angle of the focused ion beam electron beam dual-beam electron microscope, wherein the ion beam angle is 52°, the acceleration voltage is set to 30 kV, and the ion beam current is set to 0.23 nA; Deposit a tungsten protective layer on the surface of the target area with a thickness of 1 μm; The deposition process is started, and the tungsten material covers the target area under the action of the ion beam, forming the preliminary structure of the upper protective layer and the sample layer.

[0029] Specifically, by using the electron beam of a focused ion beam electron beam dual-beam electron microscope to scan the sample surface at low magnification, it is possible to quickly obtain an overall image of the sample. Combined with the precise identification of point-like distribution traces on the sample surface, the target area can be efficiently located. This method avoids blind searching and greatly improves the accuracy and efficiency of target area marking, laying a solid foundation for subsequent analysis. By adjusting the ion beam angle to 52°, setting the acceleration voltage to 30kV, and the ion beam current to 0.23nA, targeted treatment of the target area can effectively reduce the damage to the sample caused by the ion beam. On this basis, a 1μm thick tungsten protective layer is deposited on the surface of the target area to form the preliminary structure of the upper protective layer and the sample layer, isolating it from interference from external factors, enhancing the stability of the sample structure, and ensuring the integrity of the target area during subsequent processing. The dual functions of the focused ion beam electron beam dual-beam electron microscope work together, with electron beam scanning and identification, ion beam marking and protection, giving full play to the advantages of the equipment and achieving efficient cooperation between technologies. At the same time, precise setting of ion beam parameters and deposition thickness is a deep optimization of the process, ensuring the optimization of protection effect, providing reliable guarantee for subsequent research and analysis of samples, and improving the quality and reliability of the overall research.

[0030] Preferably, identifying the traces of point distribution on the sample surface according to the scanning results includes: Preprocessing the scanning electron microscopic image (BSE) obtained by scanning the sample surface to obtain a preprocessed electron microscopic image; wherein the preprocessing includes grayscale normalization processing and noise suppression processing; Retrieve the global grayscale average and grayscale standard deviation of the preprocessed electron microscopy image; Setting a dynamic threshold using the global grayscale average and grayscale standard deviation of the preprocessed electron microscopy image; The dynamic threshold is obtained by the following formula:

[0031] Where Y represents the dynamic threshold; μ G represents the global grayscale average; σ G Represents the grayscale standard deviation; A represents the connected area of ​​the neighborhood 5×5 pixel region; specifically, As a connected area-driven correction strength regulator, it achieves the following: "The more continuous the local structure, the more aggressive the threshold adjustment; the more fragmented the local structure, the more conservative the threshold adjustment." For example, when analyzing second-phase particles in an alloy, if A is large inside the particle, the correction term adapts the threshold to the grayscale inside the particle; if A is small at the particle edge, the threshold is more sensitive, accurately separating the particle from the matrix.

[0032] The pixels contained in the electron microscopy image are compared with the dynamic threshold respectively, and the pixels whose grayscale values ​​exceed the dynamic threshold are screened out as candidate pixels; Perform resonance scoring processing on the candidate pixel points to obtain the resonance score value corresponding to each candidate pixel point; Comparing the resonance score value with a preset score threshold, wherein the preset score threshold is in the range of 0.62-0.67; The candidate pixel points whose resonance score value exceeds the preset score threshold are taken as target pixel points; For the target pixel point, the resonance score value and pixel confidence are used to generate the trace possibility evaluation index corresponding to each target pixel point; The trace possibility evaluation index is obtained by the following formula:

[0033] Among them, H (x m ,y m ) represents the target pixel (x m ,y m ) corresponding trace possibility evaluation index; R(x m ,y m ) represents the target pixel (x m ,y m ) corresponding to the resonance score value; F (x m ,y m ) represents the target pixel (x m ,y m ) corresponding to the pixel confidence, where the target pixel (x m ,y m ) The corresponding pixel confidence can be obtained through the Bayesian confidence algorithm.

[0034] The trace possibility evaluation index corresponding to the target pixel is compared with a preset index threshold; wherein the preset index threshold value range is 0.42-0.51; The target pixel points whose trace possibility evaluation index is not lower than a preset index threshold are taken as trace effective pixel points, and the trace effective pixel points are integrated to form a point distribution area.

[0035] In this embodiment, resonance scoring is combined with confidence to screen pixels based on both physical properties and statistical reliability. Given the complex grayscale distribution of a sample surface caused by material heterogeneity (such as the mixing of different components, variations in surface oxide layers) and scanning noise (uneven electron beam scattering), a single grayscale threshold / feature is prone to misjudgment. However, multi-dimensional fusion can more accurately distinguish "real traces" from "interference noise." For example, on the surface of a composite material, electron microscopy images of different components may show minimal grayscale differences, but their resonance characteristics (due to differences in atomic scattering and electron transitions) vary. Combining confidence with this approach can accurately identify traces of specific components. Furthermore, the physical mechanisms of surface traces vary across samples (such as metals, semiconductors, and biomaterials) (e.g., the electron scattering pattern of metal scratches or the resonant response of protein aggregation on biofilm surfaces). However, the proposed "resonance scoring + confidence" framework is independent of the grayscale patterns of specific samples and can be adapted to different scenarios by adjusting the "resonance scoring algorithm details" and "confidence prior distribution." Compared to traditional methods that rely on fixed grayscale models, this approach offers greater versatility and expands the scope of application of the technical solution. Furthermore, by combining the resonance evaluation and confidence level described above in this embodiment, valid pixels can be obtained without noise interference, even when the index threshold is reduced to 0.42-0.51, while maximizing the target pixel validity constraint. This maximizes the accuracy of valid pixel screening without interference and reduces the miss selection rate. Furthermore, the trace likelihood evaluation index integrates the "resonance strength (R)" and "confidence level (F)." Rather than simply determining whether a trace is valid, it also quantifies the trace's "degree of validity," further improving the accuracy of trace pixel validity determination.

[0036] Specifically, a resonance scoring process is performed on the candidate pixels to obtain a resonance score value corresponding to each candidate pixel, including: Performing multi-scale feature extraction on the pre-processed electron microscopy image to obtain multi-scale features; wherein the multi-scale features include spatial scale features, material intrinsic features, geometric topology features, and dynamic process features; Extracting local features of each candidate pixel, wherein the local features of the candidate pixel include grayscale distribution, texture pattern and physical field parameters; Determine the cosine similarity S(x, y) between the feature vector formed by the local feature of each candidate pixel and the feature vector formed by the multi-scale feature; Calculation of phase gradient Φ for electron microscopy images BSE ; Establishing a topological network on the candidate pixel points, and calculating a topological continuity score for each candidate pixel point based on the topological network; The resonance score value corresponding to the candidate pixel point (x, y) is obtained by utilizing the topological continuity score of each candidate pixel point in combination with the geometric constraint factor of each candidate pixel point.

[0037] The resonance score value is obtained by the following formula:

[0038] Where R(x, y) represents the resonance score value corresponding to the candidate pixel point (x, y); S(x, y) represents the cosine similarity between the feature vector formed by the local features of the candidate pixel point (x, y) and the feature vector formed by the multi-scale features; The gradient modulus of the intrinsic phase field of the material is extracted from the BSE image using Fourier phase decoupling technology, and the modulus of its gradient (i.e., the severity of the phase change) is calculated. Y(x, y) represents the geometric constraint factor corresponding to the candidate pixel point (x, y), and its value range is (0, 1]; Г represents the topological continuity coefficient. Specifically, S(x, y) is used to analyze the second-phase particles of an alloy. For example, if a pixel point is the edge of a second-phase particle, its local grayscale, texture (local features), and global multi-scale features (spatial distribution, composition contrast, and geometric morphology of the overall second phase) have a high cosine similarity, indicating that it "belongs to the second-phase structure," which is the basic judgment for identifying phase boundaries and phase distributions. This is used to couple "physical field changes (phase gradient)" with "geometric constraints (Y)" to suppress noise caused by dramatic physical field changes but irregular geometric shapes, while enhancing realistic structures with reasonable physical field changes and matching geometric shapes. When analyzing composite materials, if a region has a large phase gradient (suspicious of a phase interface) but a low geometric constraint factor (disorganized morphology, unlike a true interface), the exponential term will weaken the score of that point, preventing it from being mistakenly identified as a "valid structure." Conversely, a true phase interface (large phase gradient + regular geometry) will be enhanced.

[0039] The topological continuity coefficient is obtained by the following formula:

[0040] Where ρ represents the topological continuity score corresponding to the target pixel obtained based on the Morse-Smale complex and persistence analysis; d represents the Riemannian manifold distance.

[0041] In this embodiment, existing techniques for extracting features from electron microscopic images often focus on a single scale (e.g., microscopic morphology) or a single type (e.g., compositional contrast). This embodiment proposes multi-scale features encompassing spatial scale, material intrinsics, geometric topology, and dynamic processes, comprehensively covering the hierarchical features of a material's microstructure from the dimensions of "static structure-dynamic evolution" and "macroscopic distribution-microscopic properties." For example, when analyzing nanocomposites, this approach not only extracts the geometric morphology (geometric topology) of nanoparticles but also correlates their spatial distribution of micron-scale agglomerations (spatial scale). Furthermore, it incorporates the intrinsic properties (material intrinsics) reflected by compositional contrast, providing a more comprehensive characterization. Local features, such as grayscale distribution, texture patterns, and physical field parameters, are supplemented to achieve "micro-to-fine" feature complementation for candidate pixels. Existing pixel analysis often focuses on grayscale or simple texture. This embodiment introduces physical field parameters (e.g., atomic number fields associated with BSE images) to more closely link pixel features to the physical nature of the material (e.g., composition and phase), providing a more accurate foundational input for subsequent resonance scoring. Existing techniques utilize BSE images to directly map composition / phase distribution using multi-focus grayscale contrast. This embodiment utilizes Fourier phase decoupling to extract the material's intrinsic phase field and then calculate the phase gradient, upgrading traditional "static contrast analysis" to "dynamic phase change analysis." For example, when analyzing phase transition interfaces, the phase gradient can accurately characterize the atomic arrangement and the severity of the compositional transition at the interface, more accurately capturing the material's physical nature than simple grayscale differences and enhancing the physical relevance of features. Morse-Smale complexes and persistence analysis are introduced to construct a topological network, supplementing features with the dimension of "topological structural continuity." Existing techniques for pixel correlation analysis often rely on simple spatial distance or grayscale similarity. This embodiment incorporates pixels into "structural network" analysis (e.g., pore connectivity and the topological morphology of phase distribution) through topological continuity scoring. For example, when analyzing porous materials, this can accurately identify continuous and isolated regions within the pore network, infusing the resonance score with topological physical meaning. Pixel scoring in existing technologies (such as significance scoring and phase recognition scoring) often relies on a single feature (such as grayscale matching and shape matching). The above technical solution of this embodiment couples cosine similarity (feature matching), phase gradient (physical field change), geometric constraint factor (spatial morphology), and topological continuity coefficient (structural correlation) to comprehensively evaluate the "resonance characteristics" of pixel points from the four dimensions of "feature matching-physical change-spatial morphology-topological correlation". For example, in the identification of heterogeneous interfaces, the cosine similarity of the component features on both sides is considered, and the phase gradient at the interface (reflecting the severity of the component transition), geometric constraint (whether the interface morphology is regular), and topological continuity (whether the interface is part of a continuous structure) are combined to make the scoring more in line with the complex reality of the material microstructure. The topological continuity coefficient is calculated based on the Riemann manifold distance, and the topological characteristics of the pixel points are expanded from "discrete space" to "manifold space" analysis.The existing technology for quantifying topological features mostly stays at the simple connected domain counting. The above technical solution of this embodiment uses the Riemann manifold distance to more accurately characterize the continuity of the topological structure in the "curved / non-Euclidean space" (such as the topological morphology of complex phase interfaces), thereby improving the quantization accuracy of topological features.

[0042] Compared to existing technologies, the technical solution described above in this embodiment addresses the problem of "incomplete feature characterization" through multi-scale and multi-type feature coverage, the problem of "weak physical-topological correlation" through phase gradient + topological network, and the problem of "poor adaptability to complex microstructures" through multi-factor coupling scoring. Ultimately, this achieves a more accurate resonant scoring of electron microscopy image pixels that better reflects the physical nature of the material. This significantly improves the accuracy and physical significance of microstructural feature extraction and analysis, particularly in scenarios such as heterogeneous interface identification, complex multiphase structure analysis, and dynamic evolution process tracking.

[0043] In order to solve the problem that the flexible film is not processed and protected in a targeted manner in the prior art, which causes the film surface to be easily deformed, please refer to Figure 1 , this embodiment provides the following technical solutions: The samples that have been initially protected are subjected to rough processing, and after the rough processing is completed, the samples are separated, including: Before rough machining, the parameters of the focused ion beam electron beam dual beam electron microscope were set. The ion beam angle of the focused ion beam electron beam dual beam electron microscope was adjusted to 52°, the acceleration voltage was 30kV, and the ion beam current was increased to 9.3nA. Centering the sample that has been preliminarily protected, the ion beam is used to mill the upper and lower sides of the target area, hollowing out the surrounding material of the target area to form a preliminary thin slice outline. After forming the preliminary thin slice outline, the ion beam angle was changed to 0°, the voltage was maintained at 30 kV, the current was reduced to 2.5 nA, and U-shaped milling was performed on the bottom and sides of the target area; After U-shaped milling, the ion beam angle was restored to 52°, the voltage was 30 kV, and the current was 2.5 nA to clean the backsplash material generated during the U-shaped milling process; After cleaning, the rough processing of the sample is completed, and the sample after rough processing is separated: For sample separation, the focused ion beam electron microscope was first switched to low current mode, with an ion beam angle of 0° and a voltage of 30 kV. The micromanipulator was lowered above the target area of ​​the rough-machined sample, and the tip of the micromanipulator was brought into contact with the surface of the target area. The micromanipulator was then fixed to the target area by ion beam-induced carbon deposition. After adhesion, lift the micro-manipulator upwards, detach it from the substrate, and rotate it 180°. Point the tip of the micro-manipulator downwards, with the bottom of the target area facing upwards. Place the rotated sample tip in contact with the sample stage, connect the sample and the sample stage with carbon, and cut off the connection between the micro-manipulator and the sample. The sample stage is rotated 180° again, so that the bottom of the target area is facing upwards. The micro-manipulation needle is lowered again to contact the target area. After connecting with carbon, the connection between the sample and the sample stage is cut off. The sample is extracted again onto the micro-manipulation needle, and the needle is rotated 180° again to restore the normal orientation of the sample. Finally, the micromanipulator is moved to the top of the copper grid and adjusted so that the target area is aligned with the copper grid. The sample is bonded to the side of the copper grid with carbon. The connection between the sample and the micromanipulator is then severed with an ion beam. The needle is then removed to complete the fixation of the sample on the copper grid. Finally, the sample separation is completed.

[0044] Specifically, before rough processing, the parameters of the focused ion beam and electron beam dual-beam electron microscope are precisely set, such as setting the ion beam angle, acceleration voltage and current to specific values, so that the ion beam can act on the sample with appropriate energy and direction, avoiding over-processing or under-processing due to inappropriate parameters. A step-by-step milling strategy is adopted, first milling the upper and lower sides of the target area and digging the surrounding materials to form a preliminary thin slice outline, and then performing U-shaped milling and backsplash material cleaning. This step-by-step processing method can effectively control the sample morphology, reduce the damage to the sample structure caused by processing stress, and ensure the integrity and original performance of the sample. Step-by-step operation also makes it easy to promptly discover and correct deviations in the processing process, improve the processing success rate and sample qualification rate. During the sample separation process, ion beam-induced carbon deposition is used to achieve adhesion between the micro-manipulation needle and the sample, as well as connection between the sample and the sample stage and copper grid. This connection method is firm and causes little damage to the sample. By rotating the micromanipulator and sample stage multiple times, combined with precise adhesion and cutting operations, the sample can be kept stable during the separation and transfer process, preventing it from falling or being damaged. Ultimately, the sample can be precisely fixed on the copper grid, providing reliable protection for subsequent observation and analysis.

[0045] The separated samples are subjected to secondary protection, including: The ion beam angle of the focused ion beam electron beam dual-beam electron microscope was adjusted to 0°, the acceleration voltage was set to 30 kV, and the ion beam current was reduced to 80 pA; Start the ion beam induced deposition process to deposit a 1 μm thick protective layer of tungsten on the lower surface of the sample fixed on the copper grid; During the deposition process, the ion beam continuously scans the bottom of the sample, evenly covering the tungsten material to form a continuous tungsten layer; After the deposition is completed, switch to electron beam mode to observe the sample cross-section to confirm that the upper protective layer, sample layer, and lower protective layer form a complete three-layer structure. The upper protective layer is the tungsten layer deposited during the initial protection, and the lower protective layer is the tungsten layer deposited during the secondary protection. Finally, the secondary protection of the sample is completed.

[0046] Specifically, the ion beam angle was set to 0°, the acceleration voltage to 30kV, and the current reduced to 80pA. This set of parameters effectively balanced processing efficiency and damage control. The 0° vertical angle ensured that the ion beam energy acted perpendicularly on the sample surface, reducing lateral sputtering damage. The 30kV voltage met the energy requirements for tungsten deposition while preventing excessive energy from causing deformation or decomposition of the thin film structure. The low current of 80pA reduced the thermal effects and bombardment damage of the ion beam on the sample, making it particularly suitable for materials such as hydrophobic flexible films that are sensitive to temperature and mechanical stress, ensuring the integrity of their chemical structure and micro-nanomorphology. A 1μm protective layer was deposited on the lower surface of the sample using tungsten as the material, utilizing its high hardness, high chemical stability, and good thermal conductivity to provide rigid support for the film. The ion beam continuously scanned the bottom of the sample to achieve uniform coverage, ensuring that the protective layer adhered tightly to the sample surface, forming a continuous and gapless protective structure. This directional deposition method not only resists the mechanical stress in subsequent thinning and sample preparation, but also prevents the film from curling and breaking due to uneven force during cross-sectional observation, maintaining its original micro-nanostructural characteristics and providing a reliable basis for subsequent imaging analysis. After deposition is completed, the electron beam mode is switched to observe the sample cross-section. By visually confirming the integrity of the three-layer structure of "upper protective layer-sample layer-lower protective layer", a closed-loop quality monitoring system is established. This visual verification method can promptly detect deposition defects (such as uneven thickness and interlayer bubbles), avoid sample failure due to improper protection, and ensure that each prepared sample meets the requirements of high-precision characterization. At the same time, this process also provides feedback for subsequent sample preparation parameter adjustments, optimizing process stability and repeatability.

[0047] In order to solve the problem in the prior art that there is no targeted thickness removal of the flexible film and no effective measurement of the final flexible film, which leads to inaccurate final film data acquisition, please refer to Figure 1 , this embodiment provides the following technical solutions: The sample after secondary protection is thinned and prepared, including: Confirm the thinning area of ​​the sample after secondary protection; After the thinning area was confirmed, the parameters of the focused ion beam electron beam dual-beam electron microscope were adjusted. The ion beam angle was set to 52°, and the acceleration voltage was divided into a rough thinning stage and a fine thinning stage. The current in the rough thinning stage was set to 0.43nA, and the current in the fine thinning stage was reduced to 80pA. The thinning area is first subjected to rough thinning. Rough thinning is performed by milling the thinning area at a 52° ion beam angle and a 0.43nA current, removing material layer by layer from the upper protective layer to the bottom until the remaining thickness is 100nm. When the milling time reaches the preset time, the SEM mode is switched to scan and the remaining thickness is measured. The thinned area is then fine-thinned by reducing the ion beam current to 80 pA and milling the thinned area. The thickness of the sample is measured after each milling until the sample thickness reaches 50 nm. After the sample is thinned, the sample surface is scanned with an ion beam. If local thickness unevenness is found after scanning, the thick area is locally refined using a current of 80 pA. Then, the surface of the sample fixed on the copper grid and thinned is cleaned; Finally, the sample thinning and preparation is completed.

[0048] Specifically, through clear step design and parameter setting, a scientific and efficient operation path is provided for sample thinning and sample preparation. First, the thinning area of ​​the sample after secondary protection is confirmed. This operation can accurately lock the part that needs to be processed, avoid blind thinning and damage to other areas of the sample, and ensure the integrity of the sample and the validity of the experimental results. At the same time, based on the area confirmation, the parameters can be adjusted and thinned in a targeted manner, which improves the accuracy and efficiency of sample preparation. The ion beam angle is fixed at 52°, and different acceleration voltages and currents are set for the rough thinning and fine thinning stages. The current of 0.43nA in the rough thinning stage can quickly remove a large amount of material, shorten the sample preparation time, and improve processing efficiency; while the current is reduced to 80pA in the fine thinning stage, which can achieve fine removal of materials and ensure the accuracy of the thinning thickness. This staged parameter setting takes into account the efficiency and accuracy of sample preparation and meets the needs of different stages. The operation process of rough thinning first and then fine thinning makes the sample preparation process more orderly and controllable. Rough thinning quickly removes the majority of material, reducing overall processing time. When approaching the target thickness, fine thinning is switched. Combined with thickness testing after each milling pass, the final sample thickness can be precisely controlled to 50nm. Subsequent refinement of localized uneven areas and surface cleaning steps further ensure sample quality, ensuring a smooth surface and uniform thickness after thinning. This provides a high-quality sample foundation for subsequent analysis and testing, significantly improving the reliability and accuracy of experimental data.

[0049] After thinning and preparing the sample, microstructure imaging is completed under low damage conditions to obtain film size and morphology data, including: The thinned sample is loaded into the sample holder of the focused ion beam electron beam dual beam electron microscope; In a focused ion beam electron beam dual beam electron microscope, the edge of the copper grid or a non-target area is first selected as the focus point, and the sample is coarsely focused at low magnification. At the same time, the electron beam avoids the target area of ​​the sample during the focusing process. Then, use low-magnification scanning to find the target area of ​​the sample on the copper grid. At the same time, magnify it to 10,000× and confirm the sample position. Perform fine focusing in a blank area away from the sample target area. After focusing is completed, the sample stage is quickly moved to translate the sample target area to the center of the field of view. After the sample is translated, a high-sensitivity CCD camera is used to expose the sample. If multiple areas are to be observed, the field of view is quickly switched in sequence, and each area is photographed no more than twice to obtain the measured image. Use the ruler tool to measure the thickness, surface undulation amplitude and microstructure feature size of the film in the measurement image; The final measurement data are the characterization data of the hydrophobic micro-nanoscale flexible film.

[0050] Specifically, the electron beam is first coarsely focused on the edge of the copper grid or a non-target area, avoiding the target area to effectively prevent direct electron beam bombardment and damage to the sample. Fine focusing is then performed on a blank area, and the target area is then moved to the center of the field of view by translating the sample stage. This step-by-step focusing strategy minimizes the physical impact on the target area of ​​the sample, ensuring that the sample remains in its original state during imaging and measurement, providing a foundation for accurate characterization. Using a focused ion beam electron beam dual-beam electron microscope, after locating the target area through low-magnification scanning, the magnification is increased to 10,000×, enabling clear capture of the sample's microstructural details. Exposure and imaging are performed with a high-sensitivity CCD camera. If multiple areas need to be observed, the field of view is quickly switched, and no more than two images are taken of each area. This ensures imaging efficiency while avoiding potential damage to the sample due to overexposure. The obtained measurement images truly reflect the sample morphology, providing a reliable basis for subsequent data measurement. Using a ruler tool, the film thickness, surface undulation amplitude, and microstructural feature dimensions in the measurement image are measured, converting the morphological characteristics of hydrophobic micro- and nano-scale flexible films into precise data. This quantitative measurement method is more scientific and convincing than qualitative observation. The final measurement data obtained as characterization data of the thin film can provide key information for material performance research, process optimization, etc., thereby enhancing the value and practicality of the entire research.

[0051] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0052] While the embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that various changes, modifications, substitutions, and alterations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A hydrophobic micro-nanoscale flexible film structure, characterized in that: It includes a flexible film body structure, a surface protection structure, a conductive structure, a supporting structure and a fixing structure; The surface protection structure is a light stroke on the film surface with an oil-based marker, which forms a dot-shaped ink distribution due to its hydrophobicity, used to mark the sampling area and protect the surface; the conductive structure is a gold vaporization layer; the supporting structure includes an upper protection layer, a sample layer and a lower protection layer; and the fixed structure is a copper grid substrate.

2. A method for characterizing a hydrophobic micro-nanoscale flexible film structure, applied to the hydrophobic micro-nanoscale flexible film structure according to claim 1, characterized in that: include: First, the film sample is pretreated, the target area of ​​the pretreated sample is marked, and the marked target area is preliminarily protected. The sample that has completed the preliminarily protection is rough-processed. After the rough processing is completed, the sample is separated, and the separated sample is secondary protected. The sample after secondary protection is thinned and sampled. After thinning and sampling, microstructure imaging is completed under low-damage conditions to obtain film size and morphology data.

3. The method for characterizing a hydrophobic micro-nanoscale flexible film structure according to claim 2, wherein: The film samples were subjected to sample pretreatment, including: Use an oil-based marker to draw a line on the surface of the hydrophobic film. After the line is drawn, the surface of the film is distributed in a dotted pattern and a surface protection structure is formed. Let the film surface stand until the pen oil dries; The dried film sample is placed in a gold evaporation device, and a layer of gold film is evaporated on the surface of the film sample; Finally, the sample pretreatment of the film sample is completed.

4. The method for characterizing a hydrophobic micro-nanoscale flexible film structure according to claim 3, characterized in that: Mark the target area of ​​the pretreated sample and perform preliminary protection on the marked target area, including: The pretreated thin film sample is placed in the sample chamber of a focused ion beam electron beam dual beam electron microscope, and the electron beam is used to scan the sample surface at a low magnification; According to the scanning results, the traces of point distribution on the sample surface are identified; The identified point-like distribution area is used as the target area, and the boundary of the target area is marked using the marking function of the focused ion beam electron beam dual beam electron microscope; Then, the target area is preliminarily protected by adjusting the ion beam angle of the focused ion beam electron beam dual-beam electron microscope, wherein the ion beam angle is 52°, the acceleration voltage is set to 30 kV, and the ion beam current is set to 0.23 nA; Deposit a tungsten protective layer on the surface of the target area with a thickness of 1 μm; The deposition process is started, and the tungsten material covers the target area under the action of the ion beam, forming the preliminary structure of the upper protective layer and the sample layer.

5. The method for characterizing a hydrophobic micro-nanoscale flexible film structure according to claim 4, characterized in that: According to the scanning results, the traces of point distribution on the sample surface are identified, including: Preprocessing the electron microscopic image obtained by scanning the sample surface to obtain a preprocessed electron microscopic image; wherein the preprocessing includes grayscale normalization processing and noise suppression processing; Retrieve the global grayscale average and grayscale standard deviation of the preprocessed electron microscopy image; Setting a dynamic threshold using the global grayscale average and grayscale standard deviation of the preprocessed electron microscopy image; The pixels contained in the electron microscopy image are compared with the dynamic threshold respectively, and the pixels whose grayscale values ​​exceed the dynamic threshold are screened out as candidate pixels; Perform resonance scoring processing on the candidate pixel points to obtain the resonance score value corresponding to each candidate pixel point; Comparing the resonance score value with a preset score threshold, wherein the preset score threshold is in the range of 0.62-0.67; The candidate pixel points whose resonance score value exceeds the preset score threshold are taken as target pixel points; For the target pixel point, the resonance score value and pixel confidence are used to generate the trace possibility evaluation index corresponding to each target pixel point; The trace possibility evaluation index corresponding to the target pixel is compared with a preset index threshold; wherein the preset index threshold value range is 0.42-0.51; The target pixel points whose trace possibility evaluation index is not lower than a preset index threshold are taken as trace effective pixel points, and the trace effective pixel points are integrated to form a point distribution area.

6. The method for characterizing a hydrophobic micro-nanoscale flexible film structure according to claim 5, characterized in that: Perform resonance scoring processing on candidate pixels to obtain the resonance score value corresponding to each candidate pixel, including: Performing multi-scale feature extraction on the pre-processed electron microscopy image to obtain multi-scale features; wherein the multi-scale features include spatial scale features, material intrinsic features, geometric topology features, and dynamic process features; Extracting local features of each candidate pixel, wherein the local features of the candidate pixel include grayscale distribution, texture pattern and physical field parameters; Determine the cosine similarity S(x, y) between the feature vector formed by the local feature of each candidate pixel and the feature vector formed by the multi-scale feature; Calculation of phase gradient Φ for electron microscopy images BSE ; Establishing a topological network on the candidate pixel points, and calculating a topological continuity score for each candidate pixel point based on the topological network; The resonance score value corresponding to the candidate pixel point (x, y) is obtained by utilizing the topological continuity score of each candidate pixel point in combination with the geometric constraint factor of each candidate pixel point.

7. The method for characterizing a hydrophobic micro-nanoscale flexible film structure according to claim 4, characterized in that: The samples that have been initially protected are subjected to rough processing, and after the rough processing is completed, the samples are separated, including: Before rough machining, the parameters of the focused ion beam electron beam dual beam electron microscope were set. The ion beam angle of the focused ion beam electron beam dual beam electron microscope was adjusted to 52°, the acceleration voltage was 30kV, and the ion beam current was increased to 9.3nA. Centering the sample that has been preliminarily protected, the ion beam is used to mill the upper and lower sides of the target area, hollowing out the surrounding material of the target area to form a preliminary thin slice outline. After forming the preliminary thin slice outline, the ion beam angle was changed to 0°, the voltage was maintained at 30 kV, the current was reduced to 2.5 nA, and U-shaped milling was performed on the bottom and sides of the target area; After U-shaped milling, the ion beam angle was restored to 52°, the voltage was 30 kV, and the current was 2.5 nA to clean the backsplash material generated during the U-shaped milling process; After cleaning, the rough processing of the sample is completed, and the sample after rough processing is separated: For sample separation, the focused ion beam electron microscope was first switched to low current mode, with an ion beam angle of 0° and a voltage of 30 kV. The micromanipulator was lowered above the target area of ​​the rough-machined sample, and the tip of the micromanipulator was brought into contact with the surface of the target area. The micromanipulator was then fixed to the target area by ion beam-induced carbon deposition. After adhesion, lift the micro-manipulator upwards, detach it from the substrate, and rotate it 180°. Point the tip of the micro-manipulator downwards, with the bottom of the target area facing upwards. Place the rotated sample tip in contact with the sample stage, connect the sample and the sample stage with carbon, and cut off the connection between the micro-manipulator and the sample. The sample stage is rotated 180° again, so that the bottom of the target area is facing upwards. The micro-manipulation needle is lowered again to contact the target area. After connecting with carbon, the connection between the sample and the sample stage is cut off. The sample is extracted again onto the micro-manipulation needle, and the needle is rotated 180° again to restore the normal orientation of the sample. Finally, the micromanipulator is moved to the top of the copper grid and adjusted so that the target area is aligned with the copper grid. The sample is bonded to the side of the copper grid with carbon. The connection between the sample and the micromanipulator is then severed with an ion beam. The needle is then removed to complete the fixation of the sample on the copper grid. Finally, the sample separation is completed.

8. The method for characterizing a hydrophobic micro-nanoscale flexible thin film structure according to claim 7, characterized in that: The separated samples are subjected to secondary protection, including: The ion beam angle of the focused ion beam electron beam dual-beam electron microscope was adjusted to 0°, the acceleration voltage was set to 30 kV, and the ion beam current was reduced to 80 pA; Start the ion beam induced deposition process to deposit a 1 μm thick protective layer of tungsten on the lower surface of the sample fixed on the copper grid; During the deposition process, the ion beam continuously scans the bottom of the sample, evenly covering the tungsten material to form a continuous tungsten layer; After the deposition is completed, switch to electron beam mode to observe the sample cross-section to confirm that the upper protective layer, sample layer, and lower protective layer form a complete three-layer structure. The upper protective layer is the tungsten layer deposited during the initial protection, and the lower protective layer is the tungsten layer deposited during the secondary protection. Finally, the secondary protection of the sample is completed.

9. The method for characterizing a hydrophobic micro-nanoscale flexible film structure according to claim 8, wherein: The sample after secondary protection is thinned and prepared, including: Confirm the thinning area of ​​the sample after secondary protection; After the thinning area was confirmed, the parameters of the focused ion beam electron beam dual-beam electron microscope were adjusted. The ion beam angle was set to 52°, and the acceleration voltage was divided into a rough thinning stage and a fine thinning stage. The current in the rough thinning stage was set to 0.43nA, and the current in the fine thinning stage was reduced to 80pA. The thinning area is first subjected to rough thinning. Rough thinning is performed by milling the thinning area at a 52° ion beam angle and a 0.43nA current, removing material layer by layer from the upper protective layer to the bottom until the remaining thickness is 100nm. When the milling time reaches the preset time, the SEM mode is switched to scan and the remaining thickness is measured. The thinned area is then fine-thinned by reducing the ion beam current to 80 pA and milling the thinned area. The thickness of the sample is measured after each milling until the sample thickness reaches 50 nm. After the sample is thinned, the sample surface is scanned with an ion beam. If local thickness unevenness is found after scanning, the thick area is locally refined using a current of 80 pA. Then, the surface of the sample fixed on the copper grid and thinned is cleaned; Finally, the sample thinning and preparation is completed.

10. The method for characterizing a hydrophobic micro-nanoscale flexible thin film structure according to claim 9, characterized in that: After thinning and preparing the sample, microstructure imaging is completed under low damage conditions to obtain film size and morphology data, including: The thinned sample is loaded into the sample holder of the focused ion beam electron beam dual beam electron microscope; In a focused ion beam electron beam dual beam electron microscope, the edge of the copper grid or a non-target area is first selected as the focus point, and the sample is coarsely focused at low magnification. At the same time, the electron beam avoids the target area of ​​the sample during the focusing process. Then, use low-magnification scanning to find the target area of ​​the sample on the copper grid. At the same time, magnify it to 10,000× and confirm the sample position. Perform fine focusing in a blank area away from the sample target area. After focusing is completed, the sample stage is quickly moved to translate the sample target area to the center of the field of view. After the sample is translated, a high-sensitivity CCD camera is used to expose the sample. If multiple areas are to be observed, the field of view is quickly switched in sequence, and each area is photographed no more than twice to obtain the measured image. Use the ruler tool to measure the thickness, surface undulation amplitude and microstructure feature size of the film in the measurement image; The final measurement data are the characterization data of the hydrophobic micro-nanoscale flexible film.

Images