Spherical coating probe of atomic force microscope, manufacturing method of spherical coating probe and atomic force microscope

Abstract

The invention discloses a spherical coated probe of an atomic force microscope, a manufacturing method of the spherical coated probe and the atomic force microscope. The spherical coated probe of the atomic force microscope comprises a microbead adhered to the lower surface of the tail end of a cantilever of the atomic force microscope; the diameter of the microbead is approximately equal to the width of the cantilever; the surface of the microbead is covered with a complete liquid dry film; the method effectively solves the problems of low measurement accuracy, low reuse rate and high price existing in the observation of the interaction force between the crude oil and the rock substrate by using a needle-point-free probe at present.

Description

Technical Field

[0001] The present disclosure relates to an atomic force microscope (AFM) probe and a method for making the same. Background Art

[0002] With the widespread application of atomic force microscopy (AFM) in micro-nanoscale surface imaging and mechanical property measurement, the selection and preparation of its probes have become the key to research.

[0003] For example, patent CN 112858730 A discloses a diamond-like carbon-coated atomic force microscope probe and a method for making the same, wherein a diamond-like carbon film is coated on the tip of the atomic force microscope probe; patent CN 114236183 A discloses an in-situ method for making nanowires at the tip of an atomic force microscope probe, which involves making a nanowire probe that can image special surface morphologies; patent CN 114236183 A discloses a method for making an atomic force microscope probe wrapped with a two-dimensional material, which coats the two-dimensional material onto the tip of the probe and is used to study the surface properties of two-dimensional planar materials.

[0004] In the study of the interaction between rocks and crude oil, it is necessary to use a specific functionalized probe to simulate the behavior of oil on the rock surface. In terms of using an atomic force microscope functional probe to observe the interaction force between crude oil and rock substrate, the CN112782430 A patent discloses a quantitative measurement method for the interaction force between crude oil and rock surface based on an atomic force microscope, which directly uses a needleless probe to immerse the droplet and measure in this state; however, due to the inconsistency of the size of the droplet itself, there is almost no way to measure and compare the force of the same size droplet at the same position on different rocks. If you want to test the effect of the same droplet on different rocks, because it cannot be guaranteed that the position of the droplet on the cantilever beam and the size of the droplet itself are completely consistent, the measurement result is inaccurate; at the same time, a blank test is usually set as a benchmark, for example, a force curve is generally measured on a mica sheet as a benchmark, and then the effect on the rock is measured. If it is only measured once, only relative results can be obtained, and due to the instability of the droplet itself, it cannot be used multiple times, that is, the number of times it is used for multiple tests is greatly limited, and the reuse rate is low.

[0005] In addition, commercial spherical probes on the market are expensive, which limits their popularity in research and industrial applications. Summary of the invention

[0006] In view of this, the present disclosure provides a spherical film-coated probe for an atomic force microscope, which solves the problems of low measurement accuracy and reusability, as well as high price, in the current use of a tipless probe for observing the interaction force between crude oil and rock substrate.

[0007] In addition, the present disclosure also provides a method for manufacturing the spherical film-coated probe, and also provides an atomic force microscope having the spherical film-coated probe.

[0008] In a first aspect, the atomic force microscope spherical film-coated probe comprises: A microbead adhered to the underside of the tip of an atomic force microscope cantilever; The diameter of the microbead is approximately equal to the width of the cantilever; The surface of the microbeads is covered with a complete dry film of liquid.

[0009] In the present disclosure and possible embodiments, the microbeads are silica microbeads.

[0010] In the present disclosure and possible embodiments, the material of the silicon microbeads is one of silicon carbide, silicon dioxide or microcrystalline silicon.

[0011] In a second aspect, the atomic force microscope comprises: The spherical coated probe described in the first aspect.

[0012] In a third aspect, a method for manufacturing the spherical film-coated probe for an atomic force microscope according to the first aspect comprises: Obtain microbeads with a diameter similar to the width of the AFM cantilever; adhering the microbead to the lower surface of the tip of an atomic force microscope cantilever; Wrapping a specified liquid outside the microbead to form a wet probe; The wet probe is dried so that the dry film of the liquid completely covers the surface of the microbead, thereby obtaining the spherical film-coated probe.

[0013] In the present disclosure and possible embodiments, the microbead is adhered to the lower surface of the end of the AFM cantilever by epoxy resin adhesive.

[0014] In the present disclosure and possible embodiments, the microbeads are spherical silica beads with a purity of 99.9%.

[0015] In the present disclosure and possible embodiments, the microbeads are immersed in the designated liquid so that the microbeads are wrapped with the designated liquid.

[0016] In the present disclosure and possible embodiments, the wet probe is dried to perform the drying process.

[0017] In the present disclosure and possible embodiments, the integrity of the dry film covering the surface of the microbeads is checked using a scanning electron microscope.

[0018] The spherical coated probe of the atomic force microscope of the present disclosure is made by adhering a microbead to the end of the atomic force microscope cantilever and coating a liquid dry film on the surface of the microbead. Due to the uniformity, continuity, integrity and stability of the dry film, and having the performance of being reusable, using this probe to observe the interaction force between crude oil and the rock substrate can significantly improve the accuracy of the test. In addition, the manufacturing method of the spherical coated probe of the atomic force microscope of the present disclosure has a simple process and low raw material prices, so it can effectively solve the problem of the high price of currently commercial spherical probes. Further, inspired by the probe manufacturing method of the present disclosure, it can be extended to applications in fields such as biomedicine, materials science and chemical engineering, and use the atomic force microscope to carry out scientific research on the interaction force between any solid and liquid, etc., to meet the research needs of specific functions. Description of the Drawings

[0019] Through the description of the embodiments of the present disclosure with reference to the following drawings, the above and other objects, features and advantages of the present disclosure will become clearer. In the drawings: Figure 1 is a schematic diagram of the manufacturing process of the coated probe of the atomic force microscope according to the embodiment of the present disclosure; Figure 2 is a schematic diagram of the quantitative measurement of the interaction force between the crude oil-rock surface based on the atomic force microscope according to the embodiment of the present disclosure; Figure 3 is the curve for evaluating the adhesion force between the oil film and the rock substrate by the moment off-curve according to the embodiment of the present disclosure; In the figure: 1 cantilever, 2 photodiode, 3 laser, 4 microsphere, 5 wet probe, 6 spherical coated probe, 7 rock substrate. Embodiments

[0020] The following describes the present disclosure based on embodiments, but it should be noted that the present disclosure is not limited to these embodiments. In the following detailed description of the present disclosure, some specific details are described in detail. However, for the parts that are not described in detail, those skilled in the art can also fully understand the present disclosure.

[0021] In addition, those of ordinary skill in the art should understand that the provided drawings are only for illustrating the purposes, features and advantages of the present disclosure, and the drawings are not actually drawn to scale. At the same time, unless the context clearly requires, the words such as "including" and "comprising" in the whole specification and claims should be interpreted as the meaning of including rather than exclusive or exhaustive; that is, it is the meaning of "including but not limited to".

[0022] The spherical coated probe of the atomic force microscope according to the embodiments of the present disclosure includes a microbead adhered to the lower surface of the end of the atomic force microscope cantilever. The diameter of the microbead is approximately equal to the width of the atomic force microscope cantilever, and the surface of the microbead is covered with a complete dry liquid film; the dry liquid film is a dry film formed after the liquid to be tested or studied dries on the surface of the microbead.

[0023] Preferably, the microbead in the embodiments of the present disclosure is a silicon microbead. Of course, microbeads of other materials can also be used as long as they do not react with the liquid to be tested or studied and do not affect the test laser, etc. Therefore, the present disclosure does not limit the material of the microbead.

[0024] Preferably, the material of the silicon microbead in the embodiments of the present disclosure is one of silicon carbide, silicon dioxide or microcrystalline silicon. More preferably, it is silicon dioxide because it is cheaper and more easily available under the premise of meeting the requirements.

[0025] The present disclosure also provides an atomic force microscope using the above-mentioned spherical coated probe at the same time.

[0026] The manufacturing method of the spherical coated probe of the atomic force microscope according to the embodiments of the present disclosure includes: Obtain a microbead with a diameter approximately equal to the width of the atomic force microscope cantilever, adhere the microbead to the lower surface of the end of the atomic force microscope cantilever, wrap a specified liquid outside the microbead to form a wet probe, and perform a drying treatment on the wet probe so that the dry film of the liquid completely covers the surface of the microbead to obtain the spherical coated probe.

[0027] Preferably, in the embodiments of the present disclosure, the microbead is adhered to the lower surface of the end of the atomic force microscope cantilever through an epoxy resin binder.

[0028] Preferably, the microbead in the embodiments of the present disclosure is a silicon dioxide round bead with a purity of 99.9%.

[0029] Preferably, in the embodiments of the present disclosure, the microbead is directly immersed in the specified liquid to be studied so that the specified liquid is wrapped outside the microbead. Of course, other means can also be used to wrap the specified liquid outside the microbead.

[0030] Preferably, the drying treatment of the wet probe in the embodiments of the present disclosure is carried out by drying, such as placing the wet probe in a heating device such as an oven, setting a temperature that will not cause changes in the performance of the liquid film, and then drying the liquid wet film on the surface of the wet probe to obtain a dry liquid film.

[0031] Because the film thickness of some liquids is very small, or the film forming process is complicated, it is uncertain whether a complete liquid dry film can be formed in the end, and sometimes the naked eye cannot clearly distinguish whether it is complete, so it is necessary to detect whether the manufactured probe meets the requirements. Preferably, the embodiment of the present disclosure uses an electron scanning microscope to check the integrity of the dry film covering the surface of the microbead, and detect whether the dry film is continuous, whether there are foreign objects, etc.

[0032] Figure 1 is a schematic diagram of the manufacturing process of the spherical film-coated probe for an atomic force microscope according to an embodiment of the present disclosure; Figure 1 As shown, the specific steps for making a spherical film-coated probe are as follows: First, a microbead 4 with a diameter similar to the width of the atomic force microscope cantilever is obtained, and the microbead 4 is adhered to the lower surface of the end of the atomic force microscope cantilever, and a specified liquid is wrapped around the microbead 4 to form a wet probe 5. The wet probe 5 is dried so that the dry film of the specified liquid completely covers the surface of the microbead 4, thereby obtaining the spherical coated probe 6 of the embodiment of the present disclosure.

[0033] The microbeads 4 can be purchased commercially or homemade. Commercially available silica microbeads with a purity of 99.9% can be selected. The diameter of the microbeads is determined according to the width of the cantilever of the atomic force microscope, and is usually 20 to 40 microns.

[0034] During the production, the silica microbeads are adhered to the lower surface of the end of the AFM probe cantilever using an epoxy resin adhesive, a designated liquid can be dropped on a glass slide using a pipette, and then the microsphere 4 is immersed in the designated liquid to produce a wet probe 5; the designated liquid of the disclosed embodiment is crude oil, and a pipette is used to drop 0.5 microliters of crude oil on a glass slide, and the microsphere 4 is immersed in the crude oil to obtain a wet oil probe.

[0035] The wet probe 5 is placed in an oven and dried at a temperature of 60° C. until a liquid dry film is formed on the surface of the microsphere 4 , thereby obtaining the spherical film-coated probe 6 of the embodiment of the present disclosure.

[0036] The obtained spherical film-coated probe 6 is observed by ESEM, and the observation contents include whether the epoxy resin excessively contaminates the cantilever, and it is required that the upper end of the cantilever is not contaminated, if contaminated, it may affect the laser reflection; at the same time, check whether the coated liquid dry film is uniform and continuous, that is, whether it is complete. If it does not meet the above requirements, the probe cannot be used for testing.

[0037] The spherical film-coated probe 6 of the embodiment of the present disclosure is used to quantitatively measure the crude oil-rock surface interaction force, specifically: The core slices of Gulong 8HC well were cut into 4mm×4mm and 2mm thick, and the surface was polished by argon ion. The spherical film-coated probe 6 was used to measure the mechanical adhesion between the core slices of Gulong 8HC well, and the steps included needle insertion and needle withdrawal, such as Figure 2 The needle insertion and needle retraction curves of the experiment are shown in Figure 3 As shown in Figure 2, the absolute value of the back-needle curve below the minimum value of zero reflects the adhesion between the rock base and the oil film.

[0038] Obviously, the spherical coated probe 6 provided by the present invention can evaluate reservoirs at the micro-nano scale; the method also ensures the uniformity and smoothness of the probe surface, thereby improving the accuracy of the measurement, which has important application value for research in fields such as petroleum engineering and geology.

[0039] In summary, the atomic force microscope spherical coated probe disclosed in the present invention is made by adhering microbeads to the end of the atomic force microscope cantilever and coating the surface of the microbeads with a liquid dry film. Due to the uniformity, continuous integrity and stability of the dry film and the ability to be repeatedly used, the use of the probe to observe the interaction force between crude oil and rock substrate can significantly improve the accuracy of the test; in addition, the atomic force microscope spherical coated probe manufacturing method disclosed in the present invention has a simple process and low raw material price, so it can effectively solve the problem of the high price of current commercial spherical probes; further, inspired by the probe manufacturing method disclosed in the present invention, it can be expanded to fields such as biomedicine, materials science and chemical engineering, and atomic force microscopes can be used to carry out scientific research on the interaction force between any solids and liquids to meet the research needs of specific functions.

[0040] The above-described embodiments are only embodiments of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present disclosure. It should be noted that, for a person of ordinary skill in the art, without departing from the concept of the present disclosure, several variations, equivalent substitutions, improvements, etc. may be made, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the attached claims.

Claims

1. A spherical film-coated probe for an atomic force microscope, It is characterized in that include: A microbead adhered to the underside of the tip of an atomic force microscope cantilever; The diameter of the microbead is approximately equal to the width of the cantilever; The surface of the microbeads is covered with a complete dry film of liquid.

2. The spherical film-coated probe for atomic force microscopy according to claim 1, Features: The microbeads are silica microbeads.

3. The spherical film-coated probe for atomic force microscopy according to claim 2, Features: The silicon microbeads are made of one of silicon carbide, silicon dioxide or microcrystalline silicon.

4. An atomic force microscope, It is characterized in that include: The spherical film-coated probe according to any one of claims 1 to 3.

5. The method for making the spherical film-coated probe for atomic force microscope according to any one of claims 1 to 3, It is characterized in that include: Obtain microbeads with a diameter similar to the width of the AFM cantilever; adhering the microbead to the lower surface of the tip of an atomic force microscope cantilever; Wrapping a specified liquid outside the microbead to form a wet probe; The wet probe is dried so that the dry film of the liquid completely covers the surface of the microbead, thereby obtaining the spherical film-coated probe.

6. The method for making a spherical film-coated probe for an atomic force microscope according to claim 5, Features: The microbead was adhered to the lower surface of the AFM cantilever tip by epoxy adhesive.

7. The method for making a spherical film-coated probe for an atomic force microscope according to claim 6, Features: The microbeads are spherical silica beads with a purity of 99.9%.

8. The method for making a spherical film-coated probe for an atomic force microscope according to claim 6 or 7, Features: The microbeads are immersed in the designated liquid so that the microbeads are surrounded by the designated liquid.

9. The method for manufacturing the spherical film-coated probe for atomic force microscope according to claim 8, Features: The wet probe is dried to perform the drying process.

10. The method for manufacturing the spherical film-coated probe for atomic force microscope according to claim 6, 7 or 9, Features: The integrity of the dry film covering the microbead surface was examined using a scanning electron microscope.

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