阅读说明：本技术 一种结构超滑器件及其制备方法 (Ultra-smooth device with structure and preparation method thereof ) 是由 郑泉水 胡恒谦 于 2019-03-26 设计创作，主要内容包括：本发明提供一种大尺度、大滑移行程并且有良好一致性和可靠性的结构超滑器件及其制备方法,所述超滑结构包括基底和多个超滑片,所述多个超滑片连接在所述基底上,所述连接使得所述超滑片的超滑面距基底表面的高度可调节。所述制备方法包括将所述超滑片转移至带有弹性连接材料的所述基底上,通过所述弹性连接材料将所述多个超滑片连接到所述基底上,通过高度调整部件调节所需高度后固化所述弹性连接材料,或者在所述基底上设置通孔,在所述多个超滑片上分别设置连接部件,连接部件对齐所述通孔,通过高度调整部件调整所述高度后将超滑片固定在所述通孔中,或者通过基底的弹性或塑形变形来调节所述高度。(The invention provides a structural ultra-smooth device with large scale, large sliding stroke and good consistency and reliability and a preparation method thereof. The preparation method comprises the steps of transferring the ultra-smooth sheets to the substrate with an elastic connecting material, connecting the ultra-smooth sheets to the substrate through the elastic connecting material, solidifying the elastic connecting material after adjusting the required height through a height adjusting component, or arranging through holes on the substrate, arranging connecting components on the ultra-smooth sheets respectively, aligning the connecting components with the through holes, fixing the ultra-smooth sheets in the through holes after adjusting the height through a height adjusting component, or adjusting the height through the elasticity or plastic deformation of the substrate.)

1. A super-slip structure comprises a substrate and a plurality of super-slip sheets, wherein the plurality of super-slip sheets are connected on the substrate, and the super-slip structure is characterized in that: the connection enables the height of the super-slip surface of the super-slip sheet from the surface of the substrate to be adjustable.

2. The ultra-smooth structure of claim 1, wherein: the connection is realized by the following modes: the height is adjusted by elastic or plastic deformation of the base or the connecting part, or by a reserved adjustment space on the base.

3. The ultra-smooth structure of claim 2, wherein: the connection is realized by the following modes: connecting the plurality of super-slip sheets to the substrate through an elastic connecting material, and then curing the elastic connecting material after adjusting the height through a height adjusting component, preferably, the elastic connecting material is epoxy resin glue, polypropylene ester glue or acrylate glue, and the volume of the elastic connecting material is 10 < -7 > nl to 10 < -3 > nl, preferably 10 < -6 > nl to 10 < -4 > nl; or through holes are formed in the substrate, connecting parts are respectively arranged on the multiple ultra-smooth sheets and aligned with the through holes, the ultra-smooth sheets are fixed in the through holes after the height is adjusted through a height adjusting part, or the height is adjusted through the elasticity or plastic deformation of the substrate.

4. The ultra-smooth structure of claim 3, wherein: the upper surface of the height adjusting part can be a plane or a smooth curved surface.

5. The ultra-smooth structure of any one of claims 1-4, wherein: the ultra-slip sheet is provided with at least one ultra-slip surface, the ultra-slip surface is an atomically smooth two-dimensional material, the diameter of the ultra-slip surface is 1-100 mu m, the thickness of each ultra-slip sheet is 100 nm-10 mu m, the diameters of different ultra-slip surfaces or the thicknesses of different ultra-slip sheets can be equal or different, preferably, the ultra-slip sheet is further provided with a connecting layer, the material of the ultra-slip sheet is preferably graphite or molybdenum disulfide, more preferably flake single crystal graphite or flake single crystal molybdenum disulfide, and the material of the connecting layer is preferably silicon dioxide.

6. The ultra-smooth structure of any one of claims 1-5, wherein: the substrate has certain flatness and rigidity, so that the substrate does not contact with a working surface when the super-slip sheet contacts with or moves relative to the working surface, and the substrate material is preferably silicon or mica or a metal sheet.

7. A method of making an ultra-smooth structure comprising:

step 1, providing a substrate;

step 2, preparing a plurality of super sliding sheets;

step 3, transferring and connecting the multiple ultra-slip sheets to the substrate;

the method is characterized in that: the connection of step 3 enables the height of the super-slip surfaces of the super-slip sheets from the surface of the substrate to be adjustable.

8. The method of claim 7, wherein:

the substrate is prepared through micromachining, the substrate has certain flatness and rigidity, so that the substrate does not contact with a working surface when the superclip is in contact with the working surface or moves relatively, the substrate is preferably made of silicon or mica or a metal sheet, and through holes or blind holes can be micromachined on the substrate.

9. The method of claim 7 or 8, the step 2 comprising:

step 2-1, at least covering a photoresist on the highly oriented pyrolytic graphite, wherein the photoresist is preferably covered in a spin coating mode;

step 2-2, the photoresist is patterned, and a plurality of photoresist islands are reserved;

step 2-3, etching the highly-oriented pyrolytic graphite so as to remove parts of the highly-oriented pyrolytic graphite which are not protected by the photoresist, thereby forming a plurality of island-shaped structures, wherein the etching is preferably reactive ion etching;

and 2-4, detecting whether the island-shaped structures have super-slip surfaces or not, wherein the island-shaped structures with the super-slip surfaces are super-slip sheets.

10. The method of any of claims 7-9, wherein: the step 3 comprises the following steps:

transferring the ultra-slip sheets to the substrate with an elastic connecting material, connecting the ultra-slip sheets to the substrate through the elastic connecting material, and then curing the elastic connecting material after adjusting the height through a height adjusting component, wherein preferably, the elastic connecting material is epoxy resin glue, polypropylene ester glue and acrylate ester glue, and the volume of the elastic connecting material is 10 < -7 > nl to 10 < -3 > nl, preferably 10 < -6 > nl to 10 < -4 > nl; or through holes are formed in the substrate, connecting parts are respectively arranged on the multiple ultra-smooth sheets and aligned with the through holes, the ultra-smooth sheets are fixed in the through holes after the height is adjusted through a height adjusting part, or the height is adjusted through the elasticity or plastic deformation of the substrate.

Technical Field

The invention relates to the field of solid structure ultra-lubricity, in particular to a large-scale and large-slip-stroke structure ultra-lubricity device and a preparation method thereof.

Background

For a long time, friction and wear problems have been closely related not only to manufacturing, but also directly to energy, environment and health. Statistically, about one third of the world's energy is consumed during friction, and about 80% of machine component failures are caused by wear. The ultra-smooth structure is one of ideal schemes for solving the problem of frictional wear, and the ultra-smooth structure refers to the phenomenon that the friction and the wear between two atomic-level smooth and non-metric contact Van der Waals solid surfaces (such as two-dimensional material surfaces of graphene, molybdenum disulfide and the like) are almost zero. In 2004, the netherlands scientist j.frenken's research group measured the friction of a few nm-sized (total about 100 carbon atoms) graphite sheet stuck on a probe when the crystal face of Highly Oriented Pyrolytic Graphite (HOPG) slides by experimental design, and the first experiment confirmed the existence of nano-scale super lubrication. However, the contact surface on the nanometer scale is actually too small compared to the dimensions required for practical applications, and not the contact surface on the macro scale, even the contact surface of the finest bearing in the most sophisticated mechanical watches, has dimensions of several hundred microns. How to realize the ultra-sliding of the large-scale structure becomes a difficult problem which is solved by scientists, however, the observed ultra-sliding of the structure is still limited to the nanometer scale, the high vacuum environment and the low speed condition. Until 2012, Liu and Zheng spring water and the like firstly realized the ultra-smoothness of the structure with micron scale, and they confirmed that the friction force in the graphite island with micron scale obviously has the basic characteristic of ultra-smoothness of the structure by utilizing HOPG and designing the experiment of 'self-retraction motion' of the graphite island.

At present, due to the influence of factors such as very difficult preparation of large-scale graphite single crystal materials, and the like, the realization of large-scale ultra-smoothness only by the preparation of single crystal materials is increasingly difficult. Researchers have proposed a solution to arrange and combine multiple small-scale ultra-smooth structures to form a large-scale structure ultra-smooth. The Chinese invention patent CN201310355985 discloses an ultra-smooth basic structure, which comprises a substrate, a plurality of island-shaped structures positioned on the substrate and a supporting layer covering the island-shaped structures, wherein a large number of graphite islands are prepared, non-ultra-smooth island-shaped structures are removed, the surface of the island-shaped structures with at least one ultra-smooth shearing surface is covered with the supporting layer, and the ultra-smooth large-scale structure can be formed. In addition, the invention also discloses a multistage ultra-slip structure formed by a plurality of ultra-slip basic structures in a mode of side-by-side expansion, independent stacking, shared stacking or combination thereof, breaks through the limitation that the ultra-slip phenomenon exists only in the microscopic scope, and can realize the ultra-slip with large scale and large slip stroke. However, the limitation of this invention is: 1. for the ultra-smooth basic structure, although large scale can be realized, the consistency of each ultra-smooth structure is poor, and the number and the positions of the island-shaped structures removed at each time are inconsistent. 2. Because the height of the ultra-smooth sliding surface is uncertain, the large-scale ultra-smooth structure is realized by controlling the consistency of the overall heights of the plurality of island-shaped structures, in order to increase the existence possibility of the ultra-smooth surface, the overall height of the island-shaped structures needs to be improved as much as possible, so that the overall height of the ultra-smooth basic structure is limited, and the preparation of the large-scale structure ultra-smooth with smaller thickness has certain limitation. 3. The sliding stroke of the ultra-smooth structure is only limited to the size of the island-shaped structure, when the larger sliding stroke is needed, the ultra-smooth structure can only be combined in a mode of arranging, overlapping and combining multi-stage structures side by side, so that the overall sliding displacement can only be the product of the size of a single island and the number of stacked layers of the island, and the reliability of the ultra-smooth structure is reduced.

Based on the factors of poor consistency, limited height, small sliding stroke, poor reliability and the like of the basic ultra-smooth structure in the patent scheme, a structural ultra-smooth device which realizes large sliding stroke and has better consistency and reliability is needed.

Disclosure of Invention

The invention aims to provide a structural ultra-smooth device which is large in size and slip stroke and has good consistency and reliability and a preparation method thereof.

The purpose of the invention is realized by the following technical scheme:

according to one aspect of the present invention, the present invention provides a super-slip structure, comprising a substrate and a plurality of super-slip sheets, wherein the plurality of super-slip sheets are connected to the substrate, and the super-slip structure is characterized in that: the connection enables the height of the super-slip surface of the super-slip sheet from the surface of the substrate to be adjustable.

According to another aspect of the invention, the connection is achieved by: the height is adjusted by elastic or plastic deformation of the base or the connecting part, or by a reserved adjustment space on the base.

According to another aspect of the invention, the connection is achieved by: connecting the plurality of super-slip sheets to the substrate through an elastic connecting material, and then curing the elastic connecting material after adjusting the height through a height adjusting component, preferably, the elastic connecting material is epoxy resin glue, polypropylene ester glue or acrylate glue, and the volume of the elastic connecting material is 10 < -7 > nl to 10 < -3 > nl, preferably 10 < -6 > nl to 10 < -4 > nl; or through holes are formed in the substrate, connecting parts are respectively arranged on the multiple ultra-smooth sheets and aligned with the through holes, the ultra-smooth sheets are fixed in the through holes after the height is adjusted through a height adjusting part, or the height is adjusted through the elasticity or plastic deformation of the substrate.

According to another aspect of the present invention, the upper surface of the height adjusting member may be a flat surface or a smoothly curved surface.

According to another aspect of the invention, the ultra-slip sheet has at least one ultra-slip surface, the ultra-slip surface is an atomically smooth two-dimensional material, the diameter of the ultra-slip surface is 1 μm to 100 μm, the thickness of each ultra-slip sheet is 100nm to 10 μm, the diameters of different ultra-slip surfaces or the thicknesses of different ultra-slip sheets can be equal or different, preferably, the ultra-slip sheet further has a connecting layer, the material of the ultra-slip sheet is preferably graphite or molybdenum disulfide, more preferably flake single crystal graphite or flake single crystal molybdenum disulfide, and the material of the connecting layer is preferably silicon dioxide.

According to another aspect of the invention, the substrate has a certain flatness and rigidity, so that the substrate does not contact with the working surface when the superclip is in contact with the working surface or moves relatively, and the substrate material is preferably silicon or mica or a metal sheet.

According to another aspect of the present invention, there is provided a method of preparing an ultra-smooth structure, comprising:

step 1, providing a substrate;

step 2, preparing a plurality of super sliding sheets;

step 3, transferring and connecting the multiple ultra-slip sheets to the substrate;

the method is characterized in that: the connection of step 3 enables the height of the super-slip surfaces of the super-slip sheets from the surface of the substrate to be adjustable.

According to another aspect of the invention, the substrate is prepared by micro machining, the substrate has certain flatness and rigidity, so that the substrate does not contact with the working surface when the ultra-slip sheet contacts with or moves relative to the working surface, the substrate is preferably made of silicon or mica or a metal sheet, and through holes or blind holes can be micro machined in the substrate.

According to another aspect of the present invention, the step 2 comprises:

step 2-1, at least covering a photoresist on the highly oriented pyrolytic graphite, wherein the photoresist is preferably covered in a spin coating mode;

step 2-2, the photoresist is patterned, and a plurality of photoresist islands are reserved;

step 2-3, etching the highly-oriented pyrolytic graphite so as to remove parts of the highly-oriented pyrolytic graphite which are not protected by the photoresist, thereby forming a plurality of island-shaped structures, wherein the etching is preferably reactive ion etching;

and 2-4, detecting whether the island-shaped structures have super-slip surfaces or not, wherein the island-shaped structures with the super-slip surfaces are super-slip sheets.

According to another aspect of the present invention, the step 3 comprises:

transferring the ultra-slip sheets to the substrate with an elastic connecting material, connecting the ultra-slip sheets to the substrate through the elastic connecting material, and then curing the elastic connecting material after adjusting the height through a height adjusting component, wherein preferably, the elastic connecting material is epoxy resin glue, polypropylene ester glue and acrylate ester glue, and the volume of the elastic connecting material is 10 < -7 > nl to 10 < -3 > nl, preferably 10 < -6 > nl to 10 < -4 > nl; or through holes are formed in the substrate, connecting parts are respectively arranged on the multiple ultra-smooth sheets and aligned with the through holes, the ultra-smooth sheets are fixed in the through holes after the height is adjusted through a height adjusting part, or the height is adjusted through the elasticity or plastic deformation of the substrate.

According to another aspect of the present invention, the substrate material may be monocrystalline silicon, quartz, pyrex, GaAs, AlTiC, Si3N4, metal, polymer, etc., and may be a single material or a composite material.

According to another aspect of the invention, the substrate may be a rigid material or an elastomeric material.

According to another aspect of the invention, the base material structure may be a planar, curved, thin sheet-like solid material with grooves or perforations. The substrate shape may be square, rectangular, circular, polygonal, or irregular.

According to another aspect of the invention, the substrate has a size ranging from 1 μm to 300 μm, preferably from 10 μm to 100 μm.

According to another aspect of the invention, the substrate may be prepared by cutting, etching, stamping or other common micromachining means.

According to another aspect of the present invention, the raw material for preparing the super-slip sheet is preferably graphite: such as Highly Oriented Pyrolytic Graphite (HOPG) or natural graphite, or the substrate may have non-contact between layers locally in the inner atoms of the material, or the ultra-smooth sheet is coated with a material with structural ultra-smooth property such as graphite or graphene on the lower surface.

According to another aspect of the invention, the ultra-slip sheet structure is a sheet structure having a lower surface with structural ultra-slip properties. The ultra-smooth sheet can be a single material, and can also form a multi-layer heterogeneous ultra-smooth structure with other connecting materials.

According to another aspect of the invention, the shape of the super-slider may be square, rectangular, circular, polygonal, or irregular. Preferably square, rectangular, etc. regular shapes.

According to another aspect of the invention, the diameter of the single super-slip sheet is 1 μm to 30 μm, the diameter is the maximum distance between two points on a cross section of the super-slip sheet in a direction parallel to the substrate, the height of the super-slip sheet is 0.3nm to 10 μm, and the average interval between adjacent super-slip sheets is 1 μm to 100 μm. The area and height of the lower surface of the superclip can be the same or different.

According to another aspect of the present invention, the elastic connection material is epoxy glue, polypropylene glue, acrylate glue, etc. commonly used in the field of micro-gluing.

According to another aspect of the invention, the volume of the elastic connecting material is between 10-7nl and 10-3nl, preferably between 10-6nl and 10-4 nl.

Drawings

The invention will be further explained with reference to the drawings,

FIG. 1 is a schematic diagram of a silicon substrate with through holes and a plurality of ultra-slip sheets connected to form a large-scale ultra-slip structure according to a first embodiment of the invention.

Fig. 2 is a schematic diagram showing a silicon substrate with grooves and a plurality of ultra-slip sheets connected to form a large-scale ultra-slip structure according to a second embodiment of the invention.

FIG. 3 is a schematic diagram showing a third embodiment of the present invention, in which an atomically smooth and flat silicon substrate is connected with a plurality of ultra-slip sheets to form a large-scale ultra-slip structure.

FIG. 4 is a schematic diagram showing a fourth embodiment of the present invention, in which an atomically smooth and flat silicon substrate and a super-slip sheet are reversely connected to form a large-scale super-slip structure.

Fig. 5 shows a schematic diagram of a thermoplastic polymer substrate and an ultra-slip sheet glued together to form a large-scale ultra-slip structure according to a fifth embodiment of the present invention.

Fig. 6 shows a schematic diagram of a large-scale flexible multistage ultra-slip structure according to a sixth embodiment of the invention.

The reference numbers are as follows: 1. the device comprises a substrate, 2, a super-slip sheet, 3, connecting materials, 4, through holes, 5, a height adjusting component, 6 and a groove.

Detailed Description

The structural ultra-smooth device and the method for manufacturing the same according to the present invention will be described in detail below with reference to the accompanying drawings.

According to a first embodiment of the present invention, as shown in fig. 1, there is provided an ultra-sliding structure, comprising a substrate 1, the material of the substrate 1 is silicon, and is provided with a plurality of through holes 4, a plurality of ultra-sliding sheets 2 are connected on the substrate 1 through the through holes 4 by connecting materials 3, and the height of the ultra-sliding surface of the ultra-sliding sheet is adjusted by the depth of the through holes and a height adjusting component 5. Wherein, a silicon substrate slice with through holes 4 is prepared by micromachining technology, the size of the substrate 1 is 140 Mum 80 Mum 10 Mum, the number of the through holes is 8, and the size is 10 Mum; the distance between the through holes is 20 μm, and the through holes are uniformly distributed on the silicon substrate. The graphite superclip 2 with the SiO2 connecting layer has the size of about 8 mu m by 8 mu m, the position distribution corresponds to the through holes 4, and the contact surface of the height adjusting component 5 and the superclip surface is an atomically smooth surface.

The preparation method of the ultra-smooth structure of the embodiment is as follows: and arranging the graphite ultra-slip sheets 2 with the SiO2 connecting layers in the same distribution with the through holes 4 on the silicon substrate, namely, the number of the ultra-slip sheets is 8, and the distance between the ultra-slip sheets is 20 mu m. And then moving the silicon substrate 1 with the through hole 4 to the position above the graphite ultra-slip sheet 2 with the SiO2 connecting layer under the control of the moving device, nesting the ultra-slip sheet 2 and the silicon substrate by using a micro manipulator after the through hole corresponds to the position of the graphite ultra-slip sheet, accurately measuring the height through an atomic force microscope, and controlling and adjusting the required distance between the lower surface of the graphite sheet and the lower surface of the silicon substrate by using the micro manipulator. Placing a light-triggered epoxy resin adhesive liquid drop 3 on a micro-needle point with a micro-nano structure groove, wherein the liquid drop spontaneously moves to a liquid storage position of the micro-needle point under the action of surface tension; the micro needle point with the liquid drop is controlled by a moving device to move to the edge position of the graphite ultra-sliding sheet 2 and form a point contact state with the graphite ultra-sliding sheet 2; and the liquid drops flow downwards along the micro-needle tip from the liquid storage position of the micro-needle tip to the surface of the target position under the action of the capillary force of the micro-nano groove on the surface of the micro-needle tip. By controlling the contact time, about 10 drops of glue are transferred at each edge position of the superclip^-6nl～10^-4nl. The relative position height of the ultra-sliding sheet 2 and the silicon substrate 1 is controlled by a micro-manipulator, visible light with the wavelength of about 400nm is used for irradiating epoxy resin glue drops for a period of time, and after the glue drops are completely cured, a large-scale ultra-sliding structure with the required height and the area of 140 microns by 80 microns is obtained.

According to a second embodiment of the invention, the silicon substrate with the groove is connected with a plurality of ultra-slip sheets to form a large-scale ultra-slip structure.

As shown in fig. 2, a super-slip structure is provided, which includes a silicon substrate 1, a plurality of grooves 6 are formed on the silicon substrate 1, and a plurality of super-slip sheets 2 are connected to the silicon substrate 1 through connecting materials 3 and the grooves 6. Wherein, a silicon substrate sheet with grooves 6 is prepared by micromachining technology, the size of the silicon substrate 1 is 140 μm 80 μm 20 μm, the number of the grooves 6 is 8, and the size is 10 μm 3 μm; the distance between the through holes is 20 μm, and the through holes are uniformly distributed on the silicon substrate. The graphite superclip 2 with the SiO2 connection layer had a size of about 8 μm by 8 μm and a position distribution corresponding to the grooves 6.

The preparation method comprises the following steps: the graphite ultra-slip sheets 2 with the SiO2 connecting layers are arranged in the same distribution with the grooves 6 on the silicon substrate, namely the number of the ultra-slip sheets is 8, and the distance between the ultra-slip sheets is 20 mu m. Placing an ultraviolet light curing acrylate glue droplet 3 on a micro-needle point with a micro-nano structure groove, wherein the droplet 3 spontaneously moves to a liquid storage position of the micro-needle point under the action of surface tension; the micro needle point with the liquid drop 3 moves to the upper part of the graphite ultra-sliding sheet 2 under the control of the moving device and forms a point contact state with the graphite ultra-sliding sheet 2; and the liquid drop 3 flows downwards along the micro-needle tip from the liquid storage position of the micro-needle tip to the surface of the target position under the action of the capillary force of the micro-nano groove on the surface of the micro-needle tip. Transfer of approximately 10 drops of glue over each superclip by controlling contact time^-6nl～10^-4nl. Then, moving the silicon substrate 1 with the groove 6 to the position above the graphite ultra-sliding sheet 2 with the SiO2 connection layer under the control of a moving device, enabling the groove 5 to correspond to the graphite ultra-sliding sheet 2, irradiating glue drops for a period of time by adopting ultraviolet light to enable the glue drops to become an elastic connection material with certain strength, and then forming a contact state between the silicon substrate and the graphite ultra-sliding sheet with the glue drops by utilizing a micro manipulator; the height is accurately measured through an atomic force microscope, certain pressure is applied to the silicon substrate through an atomic force microscope probe, and the height of the relative position of the lower surface of the super-slip sheet 2 and the lower surface of the silicon substrate 1 is adjusted. Irradiating the acrylate glue drop with ultraviolet light for a period of time, and curing the glue drop completely to obtain the product with the required height accurately controlled area of 140 μm 80 μmAnd (4) a large-scale super-smooth structure.

According to the third embodiment of the invention, the atomically smooth and flat silicon substrate is connected with a plurality of ultra-slip sheets to form a large-scale ultra-slip structure.

As shown in fig. 3, a super-slip structure is provided, which includes an atomically smooth and flat silicon substrate 1, and a plurality of super-slip sheets 2 are connected to the silicon substrate 1 through a connection material 3. Wherein, an atomically smooth and flat silicon substrate 1 sheet is prepared by a micromachining technology, and the size of the silicon substrate 1 is 140 Mum 80 Mum 20 Mum. The graphite superclip 2 with the SiO2 connecting layer has the size of 10 mu m by 10 mu m; the distance between the ultra-smooth sheets is 20 μm, and the ultra-smooth sheets are uniformly distributed on the silicon substrate.

The preparation method comprises the following steps: arranging the graphite ultra-slip sheets 2 with the SiO2 connecting layers, namely arranging the ultra-slip sheets with the number of 8 and the spacing of 20 mu m. Placing an ultraviolet light curing acrylate glue droplet 3 on a micro-needle point with a micro-nano structure groove, wherein the droplet 3 spontaneously moves to a liquid storage position of the micro-needle point under the action of surface tension; the micro needle point with the liquid drop 3 moves to the upper part of the graphite ultra-sliding sheet 2 under the control of the moving device and forms a point contact state with the graphite ultra-sliding sheet 2; and the liquid drop 3 flows downwards along the micro-needle tip from the liquid storage position of the micro-needle tip to the surface of the target position under the action of the capillary force of the micro-nano groove on the surface of the micro-needle tip. Transfer of approximately 10 drops of glue over each superclip by controlling contact time^-6nl～10^-4nl. Then, moving the silicon substrate 1 to the position above the graphite ultra-sliding sheet 2 with the SiO2 connection layer under the control of a moving device, enabling the silicon substrate to correspond to the graphite ultra-sliding sheet 2 in position, irradiating glue drops for a period of time by adopting ultraviolet light to enable the silicon substrate and the graphite ultra-sliding sheet with the glue drops to be an elastic connection material with certain strength, and then forming a contact state between the silicon substrate and the graphite ultra-sliding sheet with the glue drops by utilizing a micro manipulator; the height is accurately measured through an atomic force microscope, certain pressure is applied to the silicon substrate through an atomic force microscope probe, and the height of the relative position of the lower surface of the super-slip sheet 2 and the lower surface of the silicon substrate 1 is adjusted. And (3) irradiating the acrylate glue drops for a period of time by adopting ultraviolet light, and obtaining the large-scale ultra-smooth structure which is required to be highly accurately controlled and has the area of 140 microns by 80 microns after the glue drops are completely cured.

According to the fourth embodiment of the invention, the atomically smooth and flat silicon substrate and the ultra-smooth sheet are reversely connected to form a large-scale ultra-smooth structure.

As shown in fig. 4, a super-slip structure is provided, which includes an atomically smooth and flat silicon substrate 1, and a plurality of super-slip sheets 2 are connected to the silicon substrate 1 through a connection material 3. Wherein, an atomically smooth and flat silicon substrate 1 sheet is prepared by a micromachining technology, and the size of the silicon substrate 1 is 140 Mum 80 Mum 20 Mum. The graphite superclip 2 with the SiO2 connecting layer has the size of 10 mu m by 10 mu m; the distance between the ultra-smooth sheets is 20 μm, and the ultra-smooth sheets are uniformly distributed on the silicon substrate.

The preparation method comprises the following steps: preparing an atomically smooth silicon substrate 1 slice by a micro-processing technical means, placing an ultraviolet light curing acrylate glue droplet 3 on a micro-needle point with a micro-nano structure groove, and enabling the droplet to spontaneously move to a liquid storage position of the micro-needle point under the action of surface tension; the micro-needle point with the liquid drops moves to the upper side of the silicon substrate under the control of the moving device and forms a point contact state with the silicon substrate; and the liquid drops flow downwards along the micro-needle tip from the liquid storage position of the micro-needle tip to the surface of the target position under the action of the capillary force of the micro-nano groove on the surface of the micro-needle tip. By controlling the contact time, about 10 drops of glue are transferred at each contact point of the silicon substrate^-6nl～10^-4nl. The number of the glue drops is 8, the distance between the glue drops is 20 mu m, and the glue drops are uniformly distributed on the silicon substrate.

After the graphite ultra-slip sheet 2 is transferred and turned over by a manipulator, the ultra-slip sheet 2 with the ultra-slip shear surface on the upper surface is transferred to the silicon substrate 1 with glue drops 3, and the glue drops have certain strength and keep certain elasticity by ultraviolet irradiation. The method comprises the steps of selecting a monocrystalline silicon wafer 7 with an atomic-level smooth surface, moving the monocrystalline silicon wafer to the position above a silicon substrate 1 adhered with a superslip sheet under the control of a moving device, and controlling an atomic-level smooth plane of the monocrystalline silicon wafer to be in contact with a superslip surface of the graphite superslip sheet through a micro mechanical hand when a glue drop has certain strength and elasticity. The height is accurately measured through an atomic force microscope, certain pressure is applied to the silicon substrate through an atomic force microscope probe, and the height of the relative position of the upper surface of the super-slip sheet 2 and the upper surface of the silicon substrate 1 is adjusted. And (3) irradiating the acrylate glue drops for a period of time by adopting ultraviolet light, and obtaining the large-scale ultra-smooth structure which is required to be highly accurately controlled and has the area of 140 microns by 80 microns after the glue drops are completely cured.

According to a fifth embodiment of the present invention, a thermoplastic polymeric substrate is bonded to a super slip sheet to form a large scale super slip structure.

As shown in fig. 5, a super-slip structure is provided, which includes a thermoplastic polymer substrate 1, and a plurality of super-slip sheets 2 are connected to the silicon substrate 1 through a connection material 3. Wherein, a thermoplastic polymer substrate 1 sheet with a smooth and flat surface is prepared by a polymer plastic forming technology, and the size of the thermoplastic polymer substrate 1 is 140 Mum 80 Mum 50 Mum. The graphite superclip 2 with the SiO2 connecting layer has the size of 10 mu m by 10 mu m; the distance between the ultra-smooth sheets is 20 μm, and the ultra-smooth sheets are uniformly distributed on the thermoplastic polymer substrate.

The preparation method comprises the following steps: arranging the graphite ultra-slip sheets 2 with the SiO2 connecting layers, namely arranging the ultra-slip sheets with the number of 8 and the spacing of 20 mu m. Placing an ultraviolet light curing acrylate glue droplet 3 on a micro-needle point with a micro-nano structure groove, wherein the droplet 3 spontaneously moves to a liquid storage position of the micro-needle point under the action of surface tension; the micro needle point with the liquid drop 3 moves to the upper part of the graphite ultra-sliding sheet 2 under the control of the moving device and forms a point contact state with the graphite ultra-sliding sheet 2; and the liquid drop 3 flows downwards along the micro-needle tip from the liquid storage position of the micro-needle tip to the surface of the target position under the action of the capillary force of the micro-nano groove on the surface of the micro-needle tip. Transfer of approximately 10 drops of glue over each superclip by controlling contact time^-6nl～10^-4nl. Preparing a thermoplastic polymer substrate 1 sheet with a smooth surface after being cured at normal temperature by a polymer plastic forming technology, moving the substrate 1 above a graphite superclip 2 with a SiO2 connecting layer under the control of a moving device, enabling the substrate 1 and the graphite superclip 2 to correspond in position and then form a contact state, and irradiating glue drops by ultraviolet light to cure the glue drops. The substrate 1 is subjected to micro plastic deformation by using an external heating device, the height is accurately measured by using an atomic force microscope, a certain pressure is applied to the substrate 1 by using an atomic force microscope probe, and the relative position height or the whole structure height of the lower surface of the super-slip sheet 2 and the lower surface of the substrate 1 is adjustedAnd (4) degree. And (3) rapidly cooling to ensure that the substrate is solidified and does not deform any more, and then obtaining the large-scale ultra-smooth structure with the required highly-accurately-controlled area of 140 micrometers by 80 micrometers.

According to a sixth embodiment of the present invention, a multi-stage ultra-smooth structure and a method of making the same.

After the ultra-smooth basic structure is obtained by the preparation method, a plurality of ultra-smooth basic structures are connected by a side-by-side expansion type composition mode, an independent superposition (the substrate of the N layers of ultra-smooth structures is not used as the working plane of the N +1 layers of ultra-smooth structures), a common superposition (the substrate of the N layers of ultra-smooth structures can be simultaneously used as the working plane of the N +1 layers of ultra-smooth structures when the substrate of the N layers of ultra-smooth structures is an atomic-level smooth plane) composition mode or a composite composition mode to form a multistage ultra-smooth structure, and a specific connection method can adopt common methods such as gluing or mechanical connection according to the size of a specific embodiment.

The specific embodiment of the large-scale flexible multistage ultra-smooth structure is described as follows: 5 × 5 to 25 ultra-smooth basic structures with a size of 140 μm by 80 μm as in example three were fabricated and arranged in a side-by-side extended array of 5 × 5 squares with a side-to-side distance of 200 μm between adjacent ultra-smooth basic structures. Then a PDMS (Polydimethylsiloxane, a polymer organic silicon compound with the characteristics of optical transparency, good elasticity, no toxicity and non-flammability) sheet with the cross section area of 2mm multiplied by 1.8mm and the thickness of 1mm is taken as a global substrate, and the PDMS sheet is pasted on the upper surface of a square array consisting of ultra-smooth basic structures to form a flexible ultra-smooth multi-stage structure. Firstly, coating acrylic ester glue on one surface of PDMS, irradiating the glue by adopting ultraviolet light for a period of time to enable the glue to become an elastic connecting material with certain strength, and then forming a contact state between a PDMS substrate and a silicon substrate with a graphite ultra-slip sheet; then, the position states of the PDMS substrate and the ultra-smooth basic structure can be observed by using an optical microscope, according to the height required by the ultra-smooth multi-stage structure, a certain pressure is applied to the PDMS substrate by controlling an atomic force microscope probe, so that the PDMS substrate reaches the height required by the ultra-smooth multi-stage structure, the multi-stage ultra-smooth structure with the required height, the area of which is 2mm multiplied by 1.8mm and can be accurately controlled is obtained after the glue drops are completely cured, and the structure is a transparent, flexible and bendable sheet-shaped structure as shown in FIG. 6.

In the above embodiments, the preparation method of the super-slip sheet may refer to patent CN201310355985, specifically:

step 1, sequentially covering photoresist on the HOPG, wherein the photoresist can be covered in a spin coating mode.

And 2, patterning the photoresist and reserving a plurality of photoresist islands. The step of patterning the photoresist determines the layout of the island-like structures formed in the subsequent steps, for example, the photoresist can be patterned by using an electron beam etching method, the formed photoresist islands can have, for example, an average diameter of 1 μm to 30 μm, and the average spacing between the photoresist islands is 1 μm to 100 μm, so that the etched island-like structures also have corresponding average diameters and average spacings.

And 3, etching the substrate, and removing the part of the substrate which is not protected by the photoresist, thereby forming a plurality of island-shaped structures. The etching may be, for example, reactive ion etching.

And 4, pushing away the island-shaped structures one by using a mechanical arm to detect whether the island-shaped structures have the super-slip shear surfaces, wherein in the island-shaped structures with self-recovery performance, the HOPG sheet-shaped structures with the super-slip shear surfaces on the lower surfaces are the super-slip sheets.

In particular, each ultra-slip sheet may also have a tie layer, such as SiO 2. The preparation method comprises the following steps:

step 1, covering a connecting layer and photoresist on the HOPG in sequence, wherein the connecting layer can be SiO2, the thickness can be 50 nm-500 nm for example, and the SiO2 connecting layer can be deposited by utilizing a plasma chemical vapor deposition method. The photoresist can be covered by spin coating.

And 2, patterning the photoresist and reserving a plurality of photoresist islands. The photoresist may be patterned, for example, by electron beam etching, and the formed photoresist islands may have, for example, an average diameter of 1 μm to 30 μm and an average spacing of 1 μm to 100 μm between the photoresist islands, so that the etched island structures also have corresponding average diameters and average spacings.

And 3, etching the substrate to remove the SiO2 connecting layer which is not protected by the photoresist and part of the substrate, thereby forming a plurality of island-shaped structures with SiO2 connecting layers.

And 4, pushing away the island-shaped structures one by using a mechanical arm to detect whether the island-shaped structures have the super-smooth shearing surfaces, wherein in the island-shaped structures with self-recovery performance, the upper layer lamellar structures with the super-smooth shearing surfaces on the lower surfaces are super-smooth sheets with SiO2 connecting layers.

The transfer mode of the elastic connecting material adopts the method described in patent CN105036052, in particular to a method for transferring a glue drop with a micro-needle point with an orientation structure, and the method comprises the steps of placing or supplementing a liquid drop on the micro-needle point with a micro-nano structure groove, and the liquid drop spontaneously moves to a liquid storage position of the micro-needle point under the action of surface tension; the micro-needle point with the liquid drop is moved to a target position under the control of a moving device to form a point contact state with the target position; and the liquid drops flow downwards along the micro-needle tip from the liquid storage position of the micro-needle tip to the surface of the target position under the action of the capillary force of the micro-nano groove on the surface of the micro-needle tip. The glue drops are cured to form the elastic connecting material.

The curing method of the elastic connecting material can be a time curing method, a heat curing method or a light curing method.

Through the specific embodiment of the invention, the ultra-slip device can intuitively realize the ultra-slip with large scale and large slip stroke, which greatly breaks through the limitation that the ultra-slip can only be realized in the micro scale.

The above-described embodiments are only a few preferred embodiments of the present invention, and the present invention is not limited to these embodiments, and other variations should be allowed. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, structures, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Variations that fall within the scope of the independent claims or that can be easily ascertained by one of ordinary skill in the art based on the present invention are within the scope of the present invention.