Microcantilever, probe and atomic force microscope

Abstract

The present application provides a kind of micro-cantilever, probe and atomic force microscope, the micro-cantilever is applied to atomic force microscope, the micro-cantilever includes first area, second area and third area, the first area and the third area are respectively arranged in two ends of the micro-cantilever, the second area is between the first area and the third area, the first area is used to fix one end of the micro-cantilever, the third area is provided with needle tip for detecting sample to be measured, and the second area includes at least one micro channel.The embodiment of the present application includes at least one micro channel in the second area of micro-cantilever, to divide the micro-cantilever into smaller cantilever, each cantilever has a respective resonance frequency, the superposition of at least two smaller cantilevers can reduce the Q value of the whole micro-cantilever, so that the micro-cantilever has wider frequency amplitude peak, responds to the signal of wider frequency, and then the requirement of detecting different frequency vibration signal can be met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of atomic force microscope technology, and particularly relates to a micro-cantilever, a probe and an atomic force microscope. BACKGROUND

[0002] Atomic force microscope (AFM) is a high-resolution scanning imaging device, which detects the interaction force between the micro-cantilever and the measured sample to realize the detection function. The basic principle is that one end of a micro-cantilever which is extremely sensitive to weak force is fixed, and the other end has a very small needle tip. The needle tip contacts the sample surface. Due to the extremely weak repulsive force between the needle tip and the sample surface atoms, by controlling the constancy of this force during scanning, the micro-cantilever with the needle tip will correspond to the equipotential surface of the interaction force between the needle tip and the sample surface atoms, and will fluctuate in the direction perpendicular to the surface of the sample. By using optical detection method or tunnel current detection method, the position change of the micro-cantilever corresponding to each scanning point can be measured, so that the information of the sample surface topography can be obtained. The quality factor (Q-factor, Q value) of the micro-cantilever in the atomic force microscope represents the response condition of the micro-cantilever.

[0003] At present, the micro-cantilever usually has a high Q value. Because a higher Q value can make the probe more sensitive to the response of the sample during imaging, thereby improving the imaging resolution, therefore, the AFM probe on the market, especially the tapping mode probe, all pursue high Q value.

[0004] However, if the micro-cantilever is used as a vibration signal sensor, a higher Q value will cause the micro-cantilever to be more sensitive to the signal near the resonance frequency, but weakly or not respond to the information deviating from the resonance peak. At present, the frequency amplitude peak of the micro-cantilever is narrow, and it is difficult to detect vibration signals of different frequencies. SUMMARY

[0005] The present application provides a micro-cantilever, a probe and an atomic force microscope to solve the problem that the frequency amplitude peak of the micro-cantilever is narrow and it is difficult to detect vibration signals of different frequencies in the prior art.

[0006] The present application provides a micro-cantilever applied to an atomic force microscope, which comprises a first region, a second region and a third region. The first region and the third region are respectively arranged at two ends of the micro-cantilever. The second region is between the first region and the third region. The first region is used for fixing one end of the micro-cantilever. The third region is provided with a needle tip for detecting a measured sample. The second region comprises at least one micro-channel.

[0007] According to the micro-cantilever provided by the present application, the second region comprises two or more micro-channels.

[0008] According to a microcantilever provided by the present invention, the at least one microchannel is connected to a first edge of the second region, the first edge being an edge that coincides with the side edge of the microcantilever.

[0009] According to a microcantilever provided by the present invention, the at least one microchannel is perpendicular to the first edge.

[0010] According to a microcantilever provided by the present invention, when the second region includes two or more microchannels, the two or more microchannels are symmetrically arranged in the second region, and the depth of each microchannel is the same or different.

[0011] According to the present invention, all microchannels are not connected to the first edge of the second region, and the first edge is an edge that coincides with the side edge of the microcantilever.

[0012] According to a microcantilever provided by the present invention, when the second region includes two or more microchannels, the two or more microchannels include a first channel and M parallel second channels, wherein the first channel intersects each of the second channels, and M is an integer greater than 1.

[0013] According to the present invention, in the case of a microcantilever comprising two or more microchannels in the second region, the two or more microchannels include N-1 third channels and N parallel fourth channels, wherein the third channels are used to connect the first ends of two adjacent fourth channels, or to connect the second ends of two adjacent fourth channels, where N is an integer greater than 1.

[0014] The present invention also provides a probe, comprising: a microcantilever as described in any of the above embodiments, and a needle tip disposed on the microcantilever.

[0015] The present invention also provides an atomic force microscope, comprising: a probe base, and the probe described in the above embodiments.

[0016] This invention provides a microcantilever, probe, and atomic force microscope. The microcantilever includes at least one microchannel in its second region. The microchannel divides the microcantilever into at least two smaller cantilevers, each with its own resonant frequency. The superposition of these two smaller cantilevers reduces the overall Q value of the microcantilever, resulting in a wider frequency peak and a response to signals with a wider frequency range. This allows for the detection of vibration signals at different frequencies. Furthermore, the at least two smaller cantilevers divided by the microchannel effectively increase the vibration frequency of the microcantilever, for example, meeting the high-frequency requirements of photoacoustic signals generated by the sample. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the atomic force microscope provided in an embodiment of the present invention;

[0019] Figure 2 This is one of the structural schematic diagrams of the microcantilever provided in the embodiments of the present invention;

[0020] Figure 3 This is the second schematic diagram of the microcantilever structure provided in the embodiment of the present invention;

[0021] Figure 4 This is the third schematic diagram of the microcantilever structure provided in the embodiments of the present invention;

[0022] Figure 5 This is the fourth schematic diagram of the microcantilever structure provided in the embodiments of the present invention;

[0023] Figure 6 This is the fifth schematic diagram of the microcantilever structure provided in the embodiments of the present invention;

[0024] Figure 7 This is the sixth schematic diagram of the microcantilever structure provided in the embodiments of the present invention;

[0025] Figure 8 This is the seventh schematic diagram of the microcantilever structure provided in the embodiments of the present invention;

[0026] Figure 9 These are schematic diagrams of different forms of comb-shaped AFM probes provided in embodiments of the present invention;

[0027] Figure 10 This is a schematic diagram of the frequency amplitude curve of a conventional AFM probe in the prior art;

[0028] Figure 11 This is a schematic diagram of the frequency amplitude curve of a comb-shaped AFM probe provided in an embodiment of the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0030] To facilitate a clearer understanding of the various embodiments of the present invention, some related technical knowledge will be introduced as follows.

[0031] Atomic force microscopy uses optical detection or tunneling current detection to measure the positional changes of the microcantilever at each scanning point, thereby obtaining information about the surface morphology of the sample.

[0032] For example, a laser beam emitted by a diode laser is focused onto the back of a microcantilever by an optical system and reflected from the back of the microcantilever to a spot position detector composed of photodiodes. During sample scanning, due to the interaction forces between the atoms on the sample surface and the atoms at the tip of the microcantilever, the microcantilever will bend and undulate with the surface morphology of the sample, and the reflected beam will also deviate accordingly. Therefore, by detecting the change in the spot position using photodiodes, information about the surface morphology of the sample can be obtained.

[0033] Throughout the entire imaging process, the distance between the probe tip and the sample remains at the nanometer level. Too large a distance prevents the acquisition of information about the sample surface, while too small a distance damages both the probe tip and the sample. The feedback loop's role is to measure the intensity of the tip-sample interaction during operation, using this information to adjust the voltage applied vertically to the sample scanner. This causes the sample to expand or contract, adjusting the distance between the probe tip and the sample, and conversely, controlling the intensity of the tip-sample interaction, thus achieving feedback control. Therefore, feedback control is the core working mechanism of an atomic force microscope system. This system can employ a digital feedback control loop, allowing the user to control the characteristics of the feedback loop by setting parameters such as reference current, integral gain, and proportional gain in the control software's parameter toolbar.

[0034] The operating modes of an atomic force microscope are classified according to the form of the force between the tip and the sample. There are three main operating modes: contact mode, non-contact mode, and tapping mode.

[0035] Among them, the tapping mode is currently the most widely used imaging mode. It effectively eliminates the influence of lateral forces, provides high imaging resolution, and is suitable for observing soft and fragile samples. The tapping mode is a hybrid concept, falling between contact and non-contact modes. The cantilever oscillates above the sample surface at its resonant frequency, and the needle tip only periodically and briefly contacts or taps the sample surface. This means that the lateral force generated when the needle tip contacts the sample is significantly reduced. Therefore, the tapping mode of AFM is one of the best choices when examining delicate samples.

[0036] In the tapping mode of atomic force microscopy, the vibration signal of the microcantilever is used as a feedback signal of the force between the sample and the probe.

[0037] Once the AFM begins imaging the sample, the device immediately inputs relevant data into the system, such as surface roughness, average height, and maximum distance between peaks and valleys, for surface analysis. Simultaneously, the AFM can also perform force measurements, determining the magnitude of the force between the probe tip and the sample by measuring the cantilever's bending. In tapping mode, the AFM probe vibrates at its resonant frequency. The probe typically has a high Q value, thus avoiding the influence of noise and accurately tracking the sample surface for scanning.

[0038] The atomic force microscope (AFM) probe is a key component of atomic force microscopy. The probe consists of a microcantilever and a tip, with the tip located at one end of the microcantilever. The tip is typically conical or pyramidal in shape, with a radius of ten to tens of nanometers. The microcantilever is usually a silicon wafer or silicon nitride plate, 100–500 μm long and 1–5 μm thick. The response characteristics of the AFM probe determine the performance of the atomic force microscope. Furthermore, the microcantilever of the AFM probe determines its force constant, resonant frequency, Q-value, and other characteristics.

[0039] The Q value of a microcantilever in an atomic force microscope (AFM) probe characterizes its response. High-Q microcantilever exhibits high sensitivity for detecting resonant frequencies but has a narrow response range; low-Q microcantilever has a wider response range but reduced sensitivity. Q value and response sensitivity are a pair of mutually restrictive key parameters.

[0040] Traditional atomic force microscopy (AFM) probes have high Q values, enabling them to respond only to vibrational signals at specific frequencies within a narrow frequency range, and they cannot respond to broadband signals. Furthermore, the resonant frequencies of most existing AFM probes are in the 10–1000 kHz range, and current fabrication techniques cannot produce probes that respond to high-frequency signals such as 1–10 MHz. During AFM imaging, the vibrational signal of the AFM microcantilever can provide feedback on the force between the sample and the probe. In amplitude modulation mode, to achieve higher response sensitivity, probes typically have high Q values ​​and narrow amplitude peaks, making them more sensitive to signals near the resonant frequency, but less responsive or unresponsive to signals deviating from the resonant peak. Therefore, when using an AFM probe as a vibration detector, it can only detect vibrational signals near specific frequencies and cannot respond to high-frequency signals.

[0041] The present invention provides a microcantilever, probe, and atomic force microscope, described below with reference to the accompanying drawings.

[0042] Microcantilever can be used in atomic force microscopy. Figure 1 This is a schematic diagram of the structure of the atomic force microscope provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the atomic force microscope 100 may include: a probe base 101 and a probe 102, the probe 102 including a microcantilever 1021 and a tip 1022 disposed on the microcantilever 1021;

[0043] The probe base 101 can be used to hold the probe 102. Specifically, the probe base 101 can hold the probe 102 through one end of the microcantilever 1021. The other end of the microcantilever 1021 is provided with a needle tip 1022, which is used to detect the sample being tested.

[0044] Figure 2 This is one of the structural schematic diagrams of the microcantilever provided in the embodiments of the present invention, such as... Figure 2 As shown, the microcantilever 1021 includes a first region 1, a second region 2, and a third region 3. The first region 1 and the third region 3 are respectively disposed at both ends of the microcantilever 1021. The second region 2 is located between the first region 1 and the third region 3. The first region 1 is used to fix one end of the microcantilever 1021. The third region 3 is provided with a needle tip 1022 for probing the sample under test. The second region 2 includes at least one microchannel 21 (only one microchannel is shown as an example in the figure).

[0045] It should be noted that, if we take Figure 1 The view of the 1021 micro cantilever is the left view. Figure 2 The view of the micro cantilever 1021 is a top view.

[0046] Specifically, the probe base 101 can clamp the microcantilever 1021 through the first region 1 of the microcantilever 1021 to fix one end of the microcantilever 1021 to the clamping end of the probe base 101. The needle tip 1022 can be specifically set in the third region 3 of the microcantilever 1021. The third region 3 is usually set as a triangular region in the figure. The region between the first region 1 and the third region 3 can be understood as the second region 2.

[0047] In related technologies, in amplitude modulation mode, in order to obtain higher response sensitivity, the microcantilever of the probe usually has a high Q value and a narrow frequency amplitude peak. A higher Q value can make the probe more sensitive to the action of the sample during the imaging process, thereby improving the imaging resolution. Therefore, AFM probes on the market, especially tapping mode probes, all pursue high Q values.

[0048] However, the application of the probe in this embodiment of the invention is completely different from ordinary imaging. The probe is used as a sensor of vibration signals, rather than actively driving the probe at its resonant frequency and then using the probe to detect the force between the probe and the sample.

[0049] As sensors for vibration signals, traditional high-Q probes are clearly insufficient because the detected vibration signal is not of a specific frequency, and high-Q probes are only sensitive to signals near the resonance frequency, but respond weakly or not at all to signals deviating from the resonance peak. Therefore, when using an atomic force microscope probe as a vibration detector, it can only detect vibration signals near a specific frequency and cannot respond to high-frequency signals.

[0050] In addition, for the application scenario of detecting photoacoustic signals generated by samples, since the photoacoustic signals generated by samples are usually high-frequency and have a wide amplitude peak, the resonant frequency of a typical atomic force microscope probe is within 1MHz and the amplitude peak is narrow, which cannot meet the requirements for detecting photoacoustic signals generated by samples.

[0051] To address the aforementioned issues, this invention provides a probe for an atomic force microscope with a high-frequency, high-bandwidth response. The probe's microcantilever is equipped with a comb-like structure, which solves the problem of narrow frequency amplitude peaks in existing microcantilever systems, making it difficult to detect vibration signals of different frequencies. Furthermore, it provides the possibility for future atomic force microscope probes to be directly used to detect photoacoustic signals generated by samples.

[0052] In this embodiment of the invention, by setting at least one microchannel 21 in the second region 2 of the microcantilever 1021, the microcantilever 1021 can be divided into at least two smaller cantilevers. That is, by setting the microchannel, a comb structure is formed in the second region 2 of the microcantilever 1021. The superposition of multiple smaller cantilevers reduces the overall Q value of the microcantilever 1021, giving it a wider frequency amplitude peak and enabling it to respond to signals with a wider frequency range.

[0053] It should be noted that the Q-value is a physical parameter of the probe in an atomic force microscope (AFM), and is an important indicator of the probe's vibration characteristics. The Q-value is inversely proportional to the damping it experiences; in a liquid environment, the Q-value of the AFM probe will decrease. AFM probes with high Q-values ​​have narrower frequency peaks and are more sensitive to forces when approaching the sample, resulting in better quality imaging results.

[0054] In typical commercial tapping modes, the probe has a high Q value, making it more sensitive to signals near the resonant frequency but less sensitive to vibration signals with high bandwidth. The relationship between the force F between the sample and the probe and the Q value in tapping mode is shown in formula (1):

[0055]

[0056] Where F represents the interaction force between the sample and the probe, Q represents the quality factor of the probe, A0 represents the actual amplitude of the probe, and A set Characterizes the set amplitude of the probe in amplitude modulation mode.

[0057] As can be seen from the formula, the smaller the Q value, the greater the interaction force between the probe and the sample. Under the condition that other parameters remain unchanged during the scanning imaging process, a larger Q value can reduce the interaction force between the sample and the probe. However, when using the probe of an atomic force microscope as a vibration sensor, a probe with a low Q value can capture vibration signals better.

[0058] Because the photoacoustic signal generated by the sample has a high frequency and a wide amplitude peak, the resonant frequency of a typical atomic force microscope probe is within 1 MHz, which cannot meet the requirements for detecting the photoacoustic signal generated by the sample. The microcantilever provided in this embodiment of the invention can be used to detect the photoacoustic signal generated by the sample while realizing high-resolution imaging of atomic force microscope. The force constant C of the atomic force microscope probe and the first-order resonant frequency f in air can be calculated by the following formulas (2) and (3), respectively:

[0059]

[0060]

[0061] Where f represents the resonant frequency of the probe cantilever (kHz), C represents the force constant of the probe (N / m), T represents the thickness of the probe cantilever (μm), W represents the width of the probe cantilever (μm), L represents the length of the probe cantilever (μm), H represents the height of the probe tip (μm), ρ represents the density of the probe material (g / cm^3), and E represents the Young's modulus of the probe material (N / m^2).

[0062] Assuming the probe material is silicon (Si) with a density of 2.33 g / cm³ and a Young's modulus of 1.69 × 10¹¹ N / m², when the thickness and width of the comb-like structure of the fabricated probe are 1 μm, and the length varies from 1 μm to 10 μm, the resonant frequency of the comb portion can be calculated to be in the range of 1–15 mHz using the formula. Even considering the damping of the liquid, the requirements for responding to high-frequency vibration signals can be met. That is, the microcantilever provided in this embodiment of the invention can meet the high-frequency requirements for detecting photoacoustic signals generated by the sample.

[0063] Optionally, in order to reduce the Q value of the atomic force microscope probe and increase the probe's response to high-frequency signals, embodiments of the present invention may use a dual-beam focused ion beam processing system (e.g., Nova200 NanoLab) to process the atomic force microscope probe and prepare a microcantilever of the probe with a comb-like structure.

[0064] Specifically, a dual-beam focused ion beam processing system can be a coupling of a single-beam focused ion system and electron scanning microscopy, with the ion beam and electron beam at a certain angle, and the focal planes of the electron beam and ion beam concentric.

[0065] During the processing, electron beam imaging and ion beam processing can be used. The tilt angle of the sample stage is adjusted to make the sample perpendicular to the electron or ion beam. Liquid gallium metal can be used as the ion source, with a beam spot size of 5 nm and an ion beam current of 10 nA. The high-energy focused ion beam bombards the sample surface, transferring its kinetic energy to the molecules of the sample, generating a large number of rebound atoms. These atoms further transfer energy to surrounding atoms to form more anticarbon atoms. Rebound atoms near the surface break free from their bonds to form sputtering atoms, producing a sputtering effect that continuously etches the sample. The software for the dual-beam system can be used to generate the parallel lines, stepped lines, etc., required for processing, to obtain microcantilevered structures with a comb-like structure.

[0066] The original probe's microcantilever is the main cantilever, which is then cut using a focused ion beam processing system. Each comb-like structure can be considered a smaller microcantilever, and each microcantilever has its own resonant frequency. The superposition of multiple smaller microcantilevers reduces the overall Q value of the probe, resulting in a wider frequency amplitude peak and enabling it to respond to signals with a broader frequency range.

[0067] Alternatively, the microcantilever provided in the embodiments of the present invention can be mass-produced using methods such as casting.

[0068] In the microcantilever provided in the embodiments of the present invention, at least one microchannel is included in the second region of the microcantilever. The microchannel can divide the microcantilever into at least two smaller cantilevers, each of which has its own resonant frequency. The superposition of at least two smaller cantilevers can reduce the overall Q value of the microcantilever, making the microcantilever have a wider frequency amplitude peak and responding to signals with a wider frequency range, thereby meeting the requirements for detecting vibration signals of different frequencies. In addition, the at least two smaller cantilevers divided by the microchannel can effectively increase the vibration frequency of the microcantilever, for example, it can meet the high-frequency requirements of the photoacoustic signals generated by the sample.

[0069] Optionally, the second region may include two or more microchannels.

[0070] In the microcantilever provided in the embodiments of the present invention, the more microchannels are set, the more smaller cantilevers are divided into, and each cantilever has its own resonant frequency, which can reduce the overall Q value of the microcantilever, so that the microcantilever has a wider frequency peak and can respond to a wider range of signals.

[0071] Optionally, the at least one microchannel 21 is connected to a first edge of the second region 2, the first edge being an edge that coincides with the side edge of the microcantilever 1021.

[0072] Specifically, Figure 3 This is a second schematic diagram of the microcantilever structure provided in the embodiments of the present invention, as shown below. Figure 3 As shown, the first edge can be either the left edge a or the right edge b of the microcantilever. At least one microchannel 21 is connected to the first edge, and the microchannel 21 connected to the first edge can be used as the external microchannel of the microcantilever 1021.

[0073] Optionally, the at least one microchannel is perpendicular to the first edge.

[0074] Specifically, a microchannel 21 can be set perpendicular to the first edge.

[0075] Optionally, if the second region 2 includes two or more microchannels 21, the two or more microchannels 21 are symmetrically arranged in the second region 2, and the depth of each microchannel 21 is the same or different.

[0076] Specifically, when the second region 2 includes two or more microchannels 21, these microchannels 21 can be symmetrically arranged within the second region. The axis of symmetry for the microchannels 21 is, for example, an axis parallel to the side edge of the microcantilever 1021 and simultaneously the axis of symmetry of the microcantilever 1021.Figure 3 As shown, the axis of symmetry can be axis c in the figure.

[0077] It should be noted that the symmetrical arrangement of the microchannels 21 can prevent torsion when the probe vibrates, effectively extending the service life of the probe.

[0078] In addition, the depth of the microchannels 21 can be the same or different.

[0079] Figure 4 This is the third schematic diagram of the microcantilever structure provided in the embodiment of the present invention, as shown below. Figure 4 As shown in the figure, among the three microcantilever arms, the depth of the microchannels is the same for each individual microcantilever arm, but the depth of the microchannels in the first two microcantilever arms is less than the depth of the microchannels in the third microcantilever arm.

[0080] Figure 5 This is the fourth schematic diagram of the microcantilever structure provided in the embodiments of the present invention, as shown below. Figure 5 As shown in the figure, the depth of the microchannels is different for each of the two microcantilever arms.

[0081] It should be noted that when setting the microchannel 21 in the second region 2 of the microcantilever 1021, the following correspondence can be used as a reference for setting, and the relevant parameters are as follows: Figure 3 As shown:

[0082] 1) When the spacing x between the microchannels 21 is equal, the greater the depth y of the microchannel 21, the lower the frequency;

[0083] 2) When the depth y of the microchannels 21 is equal, the larger the spacing x between the microchannels 21, the higher the frequency;

[0084] 3) When the spacing x between microchannels 21 and the depth y of microchannels 21 are equal, the more microchannels 21 are set, the wider the frequency amplitude peak and the smaller the Q value.

[0085] It should be noted that the depth of the microchannel 21 also affects the width of the frequency amplitude peak.

[0086] Optionally, all microchannels 21 are not connected to the first edge of the second region 2, which is the edge that coincides with the side edge of the microcantilever 1021.

[0087] Specifically, Figure 6 This is the fifth schematic diagram of the microcantilever structure provided in the embodiments of the present invention, as shown below. Figure 6As shown, the first edge can be either the left edge a or the right edge b of the microcantilever. All microchannels 21 are not connected to the first edge, and the microchannels 21 that are not connected to the first edge can be regarded as the internal microchannels of the microcantilever 1021.

[0088] In one embodiment, an external microchannel and an internal microchannel can be simultaneously provided on a microcantilever 1021.

[0089] Optionally, if the second region includes two or more microchannels, the two or more microchannels include a first channel and M parallel second channels, wherein the first channel intersects each of the second channels, and M is an integer greater than 1.

[0090] Specifically, when the second region 2 includes two or more microchannels 21, the two or more microchannels 21 include a first channel 211 and M parallel second channels 212, wherein the first channel 211 intersects each of the second channels 212.

[0091] For example, such as Figure 6 As shown, five second channels 212 can be arranged horizontally parallel within the second region 2, and a first channel 211 is arranged vertically intersecting each of the second channels 212.

[0092] Figure 7 This is the sixth schematic diagram of the microcantilever structure provided in the embodiment of the present invention, as shown below. Figure 7 As shown, five second channels 212 can be arranged longitudinally parallel within the second region 2, and a first channel 211 can be arranged laterally perpendicularly to each of the second channels 212.

[0093] for Figure 7 The structure of the microcantilever is such that the microcantilever is usually slender and long, and the width of the microcantilever limits the depth of the microchannel. In this embodiment of the invention, the long side of the microcantilever can be used as the depth direction of the microchannel, resulting in smaller and slenderer cantilever segments, which are suitable for scenarios that require the detection of lower frequency signals.

[0094] Optionally, if the second region includes two or more microchannels, the two or more microchannels include N-1 third channels and N parallel fourth channels, wherein the third channels are used to connect the first ends of two adjacent fourth channels, or to connect the second ends of two adjacent fourth channels, and N is an integer greater than 1.

[0095] Specifically, when the second region 2 includes two or more microchannels 21, the two or more microchannels 21 include N-1 third channels 213 and N parallel fourth channels 214. The third channels 213 are used to connect the first ends of two adjacent fourth channels, or to connect the second ends of two adjacent fourth channels.

[0096] For example, Figure 8 This is the seventh schematic diagram of the microcantilever structure provided in the embodiment of the present invention, as shown below. Figure 8 As shown, five fourth channels 214 can be arranged horizontally in parallel within the second region 2, and four third channels 213 can be arranged vertically in the longitudinal direction. The four third channels 213 are arranged alternately to connect the second end of two adjacent fourth channels and the first end of two adjacent fourth channels.

[0097] The following example illustrates the microcantilever provided in the embodiments of the present invention.

[0098] The embodiments of the present invention can change the mechanical properties of the AFM probe by fabricating different comb-like structures on the microcantilever and processing microchannels of different depths and arrangements, thereby enabling the AFM probe to have a wider vibration response range and to respond to high-frequency signals.

[0099] The original probe's microcantilever is the main cantilever, which is cut using a focused ion beam processing system. Each comb-like structure can be considered as a smaller cantilever, and each smaller cantilever has its own resonant frequency. The superposition of multiple smaller cantilevers can reduce the overall Q value of the probe, resulting in a wider frequency response range and enabling it to respond to signals with a wider frequency range.

[0100] Alternatively, the comb tooth structure can be an external microchannel or an internal microchannel facing outwards.

[0101] Taking the comb tooth structure as an example of external microchannels, Figure 9 These are schematic diagrams of different forms of comb-shaped AFM probes provided in embodiments of the present invention.

[0102] The following describes the probe vibration signal response test. A piezoelectric crystal from an atomic force microscope system can be used as the vibration source to detect the probe's amplitude at different frequencies.

[0103] Figure 10 This is a schematic diagram of the frequency-amplitude curve of a conventional AFM probe, such as... Figure 10 As shown, the probe only responds to signals around 500kHz, indicating a narrow response range.

[0104] Figure 11 This is a schematic diagram of the frequency-amplitude curve of a comb-shaped AFM probe provided in an embodiment of the present invention, as shown below. Figure 11As shown, the response frequency of the comb-shaped AFM probe is significantly improved, achieving the highest responsivity, especially for high-frequency signals around 5.5MHz. At the same time, the response range is significantly wider than that of the ordinary AFM probe. It can be seen that the response of the comb-shaped probe to different frequencies has changed significantly, realizing a response to high-frequency signals and high bandwidth.

[0105] This invention provides an embodiment of the invention that, by fabricating a comb-like structure on the microcantilever of an atomic force microscope probe, enables the microcantilever to achieve responsiveness in a high-frequency range, while also expanding the response range of the microcantilever. This results in an atomic force microscope probe with high-frequency response and high bandwidth, while ensuring high sensitivity of the probe.

[0106] This invention provides a probe, including any of the microcantilever provided in the above embodiments, and a needle tip disposed on the microcantilever.

[0107] This invention also provides an atomic force microscope, including a probe base and the probe provided in the above embodiments.

[0108] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A microcantilever for use in an atomic force microscope, the microcantilever comprising a first region, a second region, and a third region, the first region and the third region being respectively disposed at both ends of the microcantilever, the second region being located between the first region and the third region, the first region being used to fix one end of the microcantilever, and the third region being provided with a probe tip for probing the sample under test, characterized in that, The second region includes at least one microchannel; In the case where the second region includes two or more microchannels, the two or more microchannels include a first channel and M parallel second channels, wherein the first channel intersects each of the second channels, and M is an integer greater than 1.

2. A probe, characterized in that, include: The microcantilever as described in claim 1, and the needle tip disposed on the microcantilever.

3. An atomic force microscope, characterized in that, include: The probe base, and the probe as described in claim 2.

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