A stress-driven edge-warping structural super-slick device and a preparation method thereof

Abstract

The application discloses a structure super-smooth device with stress-driven edge warping, relates to the technical field of super-smoothness, and comprises a super-smooth sheet, wherein the edges of a two-dimensional material in the super-smooth sheet are warped in a direction away from a super-smooth surface; and a film layer arranged on the entire area of a preset surface of the super-smooth sheet, wherein the film layer produces volume shrinkage and thermal stress under annealing conditions to make the edges of the super-smooth sheet warp, and the preset surface is opposite to the super-smooth surface. It can be seen that the structure super-smooth device in the application comprises the super-smooth sheet and the film layer, the film layer is arranged on the entire area of the preset surface of the super-smooth sheet, the film layer can produce volume shrinkage and thermal stress under annealing conditions, so that the edges of the super-smooth sheet are warped, that is, the edges are lifted to a certain height, thereby avoiding the contact between the edges of the super-smooth sheet and a substrate, greatly reducing the friction between the super-smooth sheet and the substrate, and avoiding abrasion. In addition, the application also provides a preparation method with the above advantages.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of super-slip, in particular to a stress-driven edge warping structural super-slip device and a preparation method thereof. BACKGROUND

[0002] Structural super-slip refers to the phenomenon that the friction and wear between two atomically smooth and non-commensurate van der Waals solid surfaces (such as graphene, molybdenum disulfide and other two-dimensional material surfaces) are almost zero. At present, the super-slip pieces in the structural super-slip device are mostly in the form of sheets or islands. When the super-slip piece contacts and moves relative to the substrate, the interface chemical bonds between the edge of the lower surface of the van der Waals material of the super-slip piece and the substrate will produce chemical bond interaction. Compared with the complete lattice in the plane of the van der Waals material, the edge part produces more significant friction and increases the risk of wear of the super-slip device.

[0003] Therefore, how to eliminate the friction between the edge of the two-dimensional material in the super-slip piece and the substrate is a technical problem to be solved by those skilled in the art. SUMMARY

[0004] The purpose of the application is to provide a stress-driven edge warping structural super-slip device and a preparation method thereof, so as to eliminate the friction and wear between the edge of the super-slip piece and the substrate.

[0005] To solve the above technical problems, the application provides a stress-driven edge warping structural super-slip device, which comprises:

[0006] A super-slip piece, wherein the edge of the two-dimensional material in the super-slip piece warps in a direction away from the super-slip surface.

[0007] A thin film layer arranged on the entire area of a preset surface of the super-slip piece, wherein the thin film layer produces volume shrinkage and thermal stress under annealing conditions to make the edge of the super-slip piece warp, and the preset surface is opposite to the super-slip surface.

[0008] Optionally, the application further comprises:

[0009] An adhesive layer arranged between the thin film layer and the super-slip piece, and the edge of the adhesive layer warps in a direction away from the super-slip surface.

[0010] Optionally, the adhesive layer is a metal layer.

[0011] Optionally, the thin film layer comprises a plurality of thin films.

[0012] Optionally, the thickness of the thin film layer is between 50 and 500 nm, and the height of the edge warping is between 0.1 and 1 nm.

[0013] Optionally, the shape of the super-slip piece is any one of a circle, a square, a rectangle and an ellipse.

[0014] Optionally, the super-slippery sheet comprises a plurality of two-dimensional materials.

[0015] Optionally, further comprising:

[0016] a substrate in contact with the super-slippery surface of the super-slippery sheet.

[0017] The present application also provides a method for preparing a stress-driven edge-warping structural super-slippery device, comprising:

[0018] forming a thin film layer on the entire area of the pre-set surface of the substrate;

[0019] etching the thin film layer and the substrate to obtain a first super-slippery island structure, the first super-slippery island structure comprising a super-slippery island and the thin film layer covering the entire area of the pre-set surface of the super-slippery island;

[0020] annealing the first super-slippery island structure in an inert gas atmosphere, the thin film layer generating volume shrinkage and thermal stress under the annealing condition to cause the edge of the super-slippery island to warp in a direction away from the super-slippery surface to form a super-slippery sheet, thereby obtaining a stress-driven edge-warping structural super-slippery device; the pre-set surface is opposite to the super-slippery surface.

[0021] Optionally, when the thin film layer is SU-8 photoresist, before forming the thin film layer on the entire area of the pre-set surface of the substrate, further comprising:

[0022] depositing an adhesion layer on the entire area of the pre-set surface of the substrate;

[0023] etching the adhesion layer and the substrate to obtain a second super-slippery island structure, the second super-slippery island structure comprising a super-slippery island and the adhesion layer covering the entire area of the pre-set surface of the super-slippery island;

[0024] Correspondingly, forming a thin film layer on the entire area of the pre-set surface of the substrate comprises:

[0025] coating SU-8 photoresist on the second super-slippery island structure;

[0026] Correspondingly, etching the thin film layer and the substrate to obtain a first super-slippery island structure comprises:

[0027] etching the SU-8 photoresist to obtain a third super-slippery island structure, the third super-slippery island structure comprising a super-slippery island, the adhesion layer and the SU-8 photoresist stacked on the entire area of the pre-set surface of the super-slippery island;

[0028] Correspondingly, annealing the first super-slippery island structure, the thin film layer generating volume shrinkage and thermal stress under the annealing condition to cause the edge of the super-slippery island to warp in a direction away from the super-slippery surface to form a super-slippery sheet comprises:

[0029] The third super slippery island structure is annealed, and the SU-8 photoresist generates volume shrinkage and thermal stress under the annealing condition to make the edge of the super slippery island warp in a direction away from the super slippery surface to form a super slippery sheet, and make the edge of the adhesion layer warp in a direction away from the super slippery surface.

[0030] The structural super slippery device driven by stress to warp the edge provided in the application comprises: a super slippery sheet, the edge of a two-dimensional material in the super slippery sheet warps in a direction away from the super slippery surface; and a thin film layer arranged on the entire area of a preset surface of the super slippery sheet, wherein the thin film layer generates volume shrinkage and thermal stress under the annealing condition to make the edge of the super slippery sheet warp, and the preset surface is opposite to the super slippery surface.

[0031] It can be seen that the structural super slippery device in the application comprises a super slippery sheet and a thin film layer, the thin film layer is arranged on the entire area of a preset surface of the super slippery sheet, the thin film layer can generate volume shrinkage and thermal stress under the annealing condition, so that the edge of the super slippery sheet warps, that is, the edge part is lifted to a certain height, so as to avoid the contact between the edge of the super slippery sheet and the substrate, eliminate the friction force between the super slippery sheet and the substrate, and avoid the abrasion.

[0032] In addition, the application also provides a preparation method with the above advantages. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

[0034] Figure 1 The structural schematic diagram of the structural super slippery device driven by stress to warp the edge provided in the application;

[0035] Figure 2 The structural schematic diagram of another structural super slippery device driven by stress to warp the edge provided in the application;

[0036] Figure 3 The flow chart of the preparation method of the structural super slippery device driven by stress to warp the edge provided in the application;

[0037] Figure 4 The flow chart of another preparation method of the structural super slippery device driven by stress to warp the edge provided in the application;

[0038] Figures 5 to 9A stress-driven edge warping structural superlubricity device preparation process flowchart provided by an embodiment of the present application is as follows:

[0039] Figures 10 to 15 Another stress-driven edge warping structural superlubricity device preparation process flowchart provided by an embodiment of the present application is as follows:

[0040] In the figure, 1. superlubricity sheet, 2. thin film layer, 3. adhesive layer, 4. substrate, 5. SU-8 photoresist, 6. highly oriented pyrolytic graphite, 7. silicon nitride thin film, 8. photoresist. DETAILED DESCRIPTION

[0041] In order to make the personnel in the technical field better understand the present application, the present application will be further described in detail below in combination with the drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts fall within the scope of protection of the present application.

[0042] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the concept of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0043] As described in the background section, at present, when the superlubricity sheet in the structural superlubricity device moves relative to the substrate, there is an interface chemical bond between the edge of the lower surface of the superlubricity sheet and the substrate, which causes extremely low friction, so that there is extremely low wear in the structural superlubricity device.

[0044] Therefore, the present application provides a stress-driven edge warping structural superlubricity device, please refer to Figure 1 , comprising:

[0045] A superlubricity sheet 1, the edge of the two-dimensional material in the superlubricity sheet 1 warps in the direction away from the superlubricity surface;

[0046] A thin film layer 2 provided on the entire area of the preset surface of the superlubricity sheet 1, wherein the thin film layer 2 generates volume shrinkage and thermal stress under annealing conditions to make the edge of the superlubricity sheet 1 warp, and the preset surface is opposite to the superlubricity surface.

[0047] It should be pointed out that the structure of the thin film layer 2 is not limited in the present application, for example, the thin film layer 2 is a single-layer thin film, or the thin film layer 2 includes multiple thin films.

[0048] The material of the thin film layer 2 includes, but is not limited to, a high molecular polymer material, an oxide dielectric material, and a nitride dielectric material, as long as the volume shrinkage and thermal stress can be generated under the annealing condition to drive the edge of the super-smooth sheet 1 to generate the warping. For example, the thin film layer 2 can be a silicon nitride film. During the annealing process, the Si-H and N-H bonds in the silicon nitride film are broken, and hydrogen atoms form hydrogen gas and diffuse out of the silicon nitride film, and dangling bonds and micropores are formed in the silicon nitride film. Such atomic rearrangement causes the volume shrinkage of the silicon nitride film, and in addition, the thermal expansion and contraction during the annealing cooling process also generates thermal stress, and the intrinsic tensile stress of about 1.4 GPa is generated during the annealing process. Under the action of the stress, the super-smooth sheet 1 below it generates warping, and the edge part is lifted by about 20 nm from the super-smooth surface. The thin film layer 2 can be SU-8 photoresist. During the annealing process, the components in the SU-8 photoresist undergo cross-linking reaction, and the volume shrinks, and at the same time, the thermal stress is also generated due to the thermal expansion and contraction during the annealing cooling process. The stress in the SU-8 photoresist causes the super-smooth sheet 1 below it to warp, and the edge is lifted by 0.1-1 μm. The thickness of the silicon nitride film can be between 100-500 nm, and the thickness of the SU-8 photoresist can be between 1-10 μm.

[0049] It should be noted that the structure of the super-smooth sheet 1 is not limited in the present application, and can be set by itself. For example, the super-smooth sheet 1 includes a plurality of layers of two-dimensional materials, or the super-smooth sheet 1 is a single-layer two-dimensional material super-smooth sheet.

[0050] The super-smooth sheet 1 can be a two-dimensional conductor super-smooth sheet, a two-dimensional semiconductor super-smooth sheet, and a two-dimensional insulating super-smooth sheet, all of which are within the protection scope of the present application. The material of the two-dimensional conductor super-smooth sheet includes, but is not limited to, graphite, graphene, niobium disulfide, and tantalum disulfide. The material of the two-dimensional semiconductor super-smooth sheet includes, but is not limited to, molybdenum disulfide, tungsten diselenide, tungsten disulfide, and black phosphorus. The material of the two-dimensional insulating super-smooth sheet includes, but is not limited to, hexagonal boron nitride and mica.

[0051] The shape of the super-smooth sheet 1 can be any one of a circular shape, a square shape, a rectangular shape, an elliptical shape, or any other irregular shape, and the present application does not make specific limitations.

[0052] Optionally, the thickness of the thin film layer 2 can be between 50-500 nm, and the edge lifting height can be between 0.1-1 nm.

[0053] In the present application, the thin film layer 2 is arranged on the entire area of the preset surface of the super-smooth sheet 1. Compared with arranging the thin film layer only on the edge area of the preset surface of the super-smooth sheet, the present application has the following advantages: 1. The tensile force of the thin film layer 2 after shrinkage is stronger, so that the edge of the two-dimensional material is warped at a larger angle, and a better super-smooth effect can be achieved; 2. The thin film layer 2 has a smaller processing difficulty, and can be applied to smaller super-smooth sheets. The present application does not need to perform patterning on the surface of the super-smooth sheet, and the process is simpler. However, if the thin film layer is arranged only on the edge of the super-smooth sheet, the tensile force is not enough, and the edge cannot be warped. 3. The thin film layer 2 fully covers the preset surface of the super-smooth sheet 1, which can be applied to various shapes, and is convenient for subsequent assembly of island covers and the like, and does not have a concave-convex structure.

[0054] The structural super-smooth device in the present application includes a super-smooth sheet 1 and a thin film layer 2. The thin film layer 2 is arranged on the entire area of the preset surface of the super-smooth sheet 1. The thin film layer 2 can generate volume shrinkage and thermal stress under annealing conditions, so that the edge of the super-smooth sheet 1 is warped, that is, the edge part is lifted to a certain height, so as to avoid contact between the edge of the super-smooth sheet 1 and the substrate, eliminate the friction force between the super-smooth sheet 1 and the substrate, and avoid wear.

[0055] Please refer to Figure 2 On the basis of the above-mentioned embodiments, in an embodiment of the present application, the stress-driven edge-warping structural super-smooth device further includes:

[0056] An adhesive layer 3 is arranged between the thin film layer 2 and the super-smooth sheet 1, and the edge of the adhesive layer 3 is warped in a direction away from the super-smooth surface.

[0057] The adhesive layer 3 can be a metal layer or other film layer that can enhance the adhesion between the thin film layer 2 and the super-smooth sheet 1. The metal layer can be a gold layer, a titanium layer, etc.

[0058] During the annealing process, the edge of the adhesive layer 3 is warped together with the edge of the super-smooth sheet 1 under the stress generated by the thin film layer 2. The thickness of the adhesive layer 3 can be 100 nm.

[0059] On the basis of any of the above-mentioned embodiments, in an embodiment of the present application, the structural super-smooth device further includes:

[0060] A substrate in contact with the super-smooth surface of the super-smooth sheet 1.

[0061] The surface of the substrate in contact with the super-smooth sheet 1 is also a super-smooth surface. Due to the edge warping of the super-smooth sheet 1, the super-smooth sheet 1 and the substrate are in point contact.

[0062] The material of the substrate can be any one of graphite, HOPG (highly oriented pyrolytic graphite), graphene, molybdenum disulfide, bismuth, molybdenum, mica.

[0063] The application also provides a preparation method of a stress-driven edge-warping structural super-smooth device, which refers to Figure 3 The method comprises the following steps:

[0064] Step S101: forming a thin film layer on the entire area of the preset surface of the substrate.

[0065] The forming method of the thin film layer can be determined according to the material of the thin film layer. For example, when the material of the thin film layer is an oxide dielectric material or a nitride dielectric material (such as silicon nitride), a plasma-enhanced chemical vapor deposition method can be used; when the material of the thin film layer is SU-8 photoresist, a spin coating method can be used to form the thin film layer.

[0066] Step S102: etching the thin film layer and the substrate to obtain a first super-smooth island structure, wherein the first super-smooth island structure comprises a super-smooth island and the thin film layer covering the entire area of the preset surface of the super-smooth island.

[0067] A photoresist is coated on the upper surface of the thin film layer, and the photoresist is exposed and developed to form a patterned mask; etching is performed according to the patterned mask to obtain the first super-smooth island structure. The etching depth of the substrate can be 1-3 μm.

[0068] After etching, the photoresist is removed.

[0069] Step S103: annealing the first super-smooth island structure in an inert gas atmosphere, wherein the thin film layer generates volume shrinkage and thermal stress under the annealing condition, so that the edges of the two-dimensional material in the super-smooth island warp in a direction away from the super-smooth surface to form a super-smooth sheet, thereby obtaining a stress-driven edge-warping structural super-smooth device; the preset surface is opposite to the super-smooth surface.

[0070] The annealing condition is determined according to the material of the thin film layer. For example, when the thin film layer is a silicon nitride film, the annealing temperature can be 400-800℃, and the annealing time can be 10-60 minutes; when the thin film layer is SU-8 photoresist, the annealing temperature can be 200℃, and the annealing time can be 20 minutes.

[0071] The structural super-smooth device prepared by the method comprises a super-smooth sheet and a thin film layer, the thin film layer is located on the entire area of the preset surface of the super-smooth sheet, the thin film layer can generate volume shrinkage and thermal stress under annealing conditions, so that the edge of the super-smooth sheet is warped, that is, the edge part is lifted to a certain height, thereby avoiding the contact between the edge of the super-smooth sheet and the substrate, greatly reducing the friction between the super-smooth sheet and the substrate, and avoiding wear.

[0072] The application also provides another method for preparing a structural super-smooth device with stress-driven edge warping, please refer to Figure 4 When the thin film layer is SU-8 photoresist, the method comprises the following steps:

[0073] Step S201: depositing an adhesion layer on the entire area of the preset surface of the substrate.

[0074] When the adhesion layer 3 is a metal layer, the adhesion layer 3 can be deposited on the substrate 4 by using an electron beam evaporation method, and the thickness of the metal layer can be 100 nm, as shown in Figure 5 .

[0075] Step S202: etching the adhesion layer and the substrate to obtain a second super-smooth island structure, the second super-smooth island structure comprises super-smooth islands and the adhesion layer covering the entire area of the preset surface of the super-smooth islands.

[0076] The photoresist is spin-coated on the adhesion layer, and a pattern of graphite islands with a size of 4-10 μm is obtained by photolithography. The adhesion layer 3 and the substrate 4 are etched away in sequence by using a reactive ion etching method (the etching depth of the substrate is 1-3 μm) to obtain a second super-smooth island structure, as shown in Figure 6 . After etching is completed, the photoresist is removed.

[0077] Step S203: coating SU-8 photoresist on the second super-smooth island structure.

[0078] The SU-8 photoresist 5 is distributed on the surface of the adhesion layer 3 and the gap between the super-smooth islands, as shown in Figure 7 . The thickness of the SU-8 photoresist is between 1-10 μm.

[0079] Step S204: etching the SU-8 photoresist to obtain a third super-smooth island structure, the third super-smooth island structure comprises super-smooth islands, the adhesion layer and the SU-8 photoresist which are laminated on the entire area of the preset surface of the super-smooth islands.

[0080] The same pattern as that in step S202 is used for overlay etching to obtain a third super-smooth island structure, as shown in Figure 8 .

[0081] Step S205: annealing the third super-smooth island structure in vacuum or inert gas atmosphere, the volume shrinkage and thermal stress of the SU-8 photoresist under the annealing condition make the edges of the two-dimensional material in the super-smooth island warp in the direction away from the super-smooth surface to form super-smooth sheets, and make the edges of the adhesion layer warp in the direction away from the super-smooth surface, to obtain a structure super-smooth device with stress-driven edge warping; the preset surface is opposite to the super-smooth surface.

[0082] In vacuum or inert gas atmosphere, annealing at 200℃ for about 20min, to obtain a structure super-smooth device, as shown in Figure 9

[0083] In this embodiment, the adhesion layer is deposited between the SU-8 photoresist and the super-smooth sheet, so as to enhance the adhesion between the SU-8 photoresist and the super-smooth sheet, and thus the edges of the super-smooth sheet can well warp in the annealing process.

[0084] Next, taking the deposition of a silicon nitride film on highly oriented pyrolytic graphite as an example, the preparation method in the present application is further introduced.

[0085] Step 1, please refer to Figure 10 , a layer of silicon nitride film 7 is deposited on the surface of the highly oriented pyrolytic graphite 6 by plasma enhanced chemical vapor deposition, and the thickness of the silicon nitride film 7 is 100-500nm;

[0086] Step 2, please refer to Figures 11 to 12 , spin-coat photoresist 8 on the surface of the silicon nitride film 7 and perform electron beam exposure, to obtain a graphite island pattern with a size of 4-10μm;

[0087] Step 3, please refer to Figures 13 to 14 , the silicon nitride film 7 and the highly oriented pyrolytic graphite 6 are etched away in sequence by reactive ion etching, and the photoresist is removed, to obtain a graphite island structure, wherein the etching depth of the highly oriented pyrolytic graphite 6 is 1-3μm;

[0088] Step 4, please refer to Figure 15 , annealing the obtained graphite island structure in inert gas atmosphere at 400-800℃ for 10-60min, to obtain a structure super-smooth device.

[0089] In the present specification, each embodiment is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts are described in the method part.

[0090] ​The structure super-smooth device of stress-driven edge warping and the preparation method thereof provided by the present application are described in detail above. The principles and implementation manners of the present application are described by applying specific examples, and the above description of the examples is only used to help understand the method of the present application and the core idea thereof. It should be pointed out that, for those skilled in the art, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A stress-driven edge-wrinkled structural super-slip device, characterized in that, The application relates to a super-slippery device, comprising: a super-slippery sheet, wherein the edges of the two-dimensional material in the super-slippery sheet are warped in a direction away from the super-slippery surface; a thin film layer provided on the entire surface of the super-slippery sheet, wherein the thin film layer generates volume shrinkage and thermal stress under annealing conditions to make the edges of the super-slippery sheet warped, and the preset surface is opposite to the super-slippery surface; an adhesive layer provided between the thin film layer and the super-slippery sheet, and the edges of the adhesive layer are warped in a direction away from the super-slippery surface; wherein during the annealing process, the edges of the adhesive layer are warped together with the edges of the super-slippery sheet under the stress generated by the thin film layer; a substrate in contact with the super-slippery surface of the super-slippery sheet, and the surface of the substrate in contact with the super-slippery sheet is a super-slippery surface.

2. The structured super-slip device of claim 1, wherein, The adhesive layer is a metal layer.

3. The structured super-slip device of claim 1, wherein, The thin film layer comprises a plurality of thin film layers.

4. The structured superlubricity device of claim 1, wherein, The thickness of the thin film layer is between 50 and 500 nm, and the height of the edge warping is between 0.1 and 1 nm.

5. The structured superlubricity device of claim 1, wherein, The shape of the super-slippery sheet is any one of a circle, a square, a rectangle and an ellipse.

6. The structured superlubricity device of claim 1, wherein, The super-slippery sheet comprises a plurality of two-dimensional materials.

7. A method for fabricating a stress-driven edge-warping structural super- slippery device based on the structural super-slippery device of claim 1, characterized in that, The application also relates to a method for manufacturing a super-slippery device, comprising: forming a thin film layer on the entire surface of a preset surface of a substrate; etching the thin film layer and the substrate to obtain a first super-slippery island structure, wherein the first super-slippery island structure comprises a super-slippery island and the thin film layer covering the entire surface of a preset surface of the super-slippery island; performing annealing treatment on the first super-slippery island structure in an inert gas atmosphere, wherein the thin film layer generates volume shrinkage and thermal stress under annealing conditions to make the edges of the two-dimensional material in the super-slippery island warped in a direction away from the super-slippery surface to form a super-slippery sheet, thereby obtaining a stress-driven edge warping super-slippery device; the preset surface is opposite to the super-slippery surface; before forming the thin film layer on the entire surface of the preset surface of the substrate, the method further comprises: depositing an adhesive layer on the entire surface of the preset surface of the substrate; etching the adhesive layer and the substrate to obtain a second super-slippery island structure, wherein the second super-slippery island structure comprises a super-slippery island and the adhesive layer covering the entire surface of a preset surface of the super-slippery island; correspondingly, the step of forming the thin film layer on the entire surface of the preset surface of the substrate comprises: forming the thin film layer on the second super-slippery island structure.

8. The method of claim 7, wherein the structure super-slick device is prepared by, when the thin film layer is SU-8 photoresist, the step of forming the thin film layer on the entire surface of the preset surface of the substrate comprises: coating SU-8 photoresist on the second super-slippery island structure; correspondingly, the step of etching the thin film layer and the substrate to obtain the first super-slippery island structure comprises: etching the SU-8 photoresist to obtain a third super-slippery island structure, wherein the third super-slippery island structure comprises a super-slippery island, the adhesive layer and the SU-8 photoresist stacked on the entire surface of a preset surface of the super-slippery island; correspondingly, the step of performing annealing treatment on the first super-slippery island structure, wherein the thin film layer generates volume shrinkage and thermal stress under annealing conditions to make the edges of the super-slippery island warped in a direction away from the super-slippery surface to form a super-slippery sheet comprises: performing annealing treatment on the third super-slippery island structure, wherein the SU-8 photoresist generates volume shrinkage and thermal stress under annealing conditions to make the edges of the super-slippery island warped in a direction away from the super-slippery surface to form a super-slippery sheet, and the edges of the adhesive layer are warped in a direction away from the super-slippery surface.

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