Nanoimprint mold, preparation method, and nanoimprint method

Abstract

The present invention relates to a nanoimprint mold, a preparation method, and a nanoimprint method. The nano-imprint mold comprises a base plate; the base plate has a first surface and a second surface opposite to each other; microstructures protruding from the second surface are formed on the second surface of the base plate; a recess which is recessed is formed on the first surface of the base plate; the base plate is further provided with a plurality of through holes passing through the bottom of the recess and the second surface; and the through holes are located beside the microstructures. In the present invention, by providing the through holes beside the microstructures, no residual imprint resist layer will be formed between the microstructures and a substrate; thus, no subsequent processing steps are required, the processing procedures and difficulty are greatly reduced, and the fidelity and quality of target nano-patterns are improved.

Description

Nanoimprinting mold, preparation method and nanoimprinting method Technical Field

[0001] This invention belongs to the field of nanoimprinting technology, specifically relating to a nanoimprinting mold, its preparation method, and a nanoimprinting method. Background Technology

[0002] Nanoimprint lithography (NIM) technology boasts advantages such as high resolution, simple process, ultra-low cost, and high productivity, making it widely used in micro- and nano-manufacturing fields like semiconductors. Currently, traditional NIM methods include thermal lithography and UV-based room-temperature lithography. However, due to the long operation cycle, excessive pressure causing template wear, and large alignment deviations in thermal lithography, more and more equipment designs are shifting towards UV-based room-temperature lithography.

[0003] In traditional UV-based room-temperature imprinting equipment, a pressure of over one atmosphere is required to ensure complete adhesion between the imprinting template and the substrate during nanoimprinting. To prevent mutual damage caused by contact between the template and substrate during imprinting, the volume of the imprinting adhesive layer on the substrate is slightly larger than the volume of the recessed structure on the imprinting template. This means that the imprinting adhesive not only completely fills the recessed structure on the imprinting template but also forms a residual imprinting adhesive layer between the raised structure and the substrate, thus isolating the imprinting template from the substrate. To further transfer the imprinted nanostructure, an additional reactive ion beam etching process is needed to remove the residual imprinting adhesive layer and expose the substrate beneath it. This significantly increases the complexity and difficulty of subsequent processing steps, affecting the fidelity of the nanostructure.

[0004] Therefore, to address the aforementioned technical problems, it is necessary to provide a nanoimprint mold, a preparation method, and a nanoimprinting method. Summary of the Invention

[0005] The purpose of this invention is to provide a nanoimprint mold, a preparation method, and a nanoimprint method, which can solve the problem of residual adhesive remaining on the substrate after nanoimprint demolding.

[0006] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution:

[0007] A nanoimprint mold includes a substrate having a first surface and a second surface disposed opposite to each other. A microstructure protruding from the second surface is formed on the second surface of the substrate, and a recessed groove is formed on the first surface of the substrate. The substrate also has a plurality of through holes penetrating the bottom of the groove and the second surface, the through holes being located beside the microstructure.

[0008] In one or more embodiments of the present invention, the microstructures are spaced apart, the through-holes are spaced apart, and the size of the through-holes is less than or equal to the size of the microstructures; and / or,

[0009] The microstructure is a columnar microstructure, and the columnar microstructures are arranged in an array with intervals. The size of the columnar microstructure is 1μm to 1000μm. The through-hole is a circular through-hole, and the circular through-holes are arranged in an array with intervals. The size of the circular through-holes is 0.8μm to 1000μm, and the size of the circular through-holes is less than or equal to the size of the columnar microstructure.

[0010] In one or more embodiments of the present invention, the depth of the groove is greater than or equal to the height of the microstructure.

[0011] In one or more embodiments of the present invention, the groove is provided with a plurality of partitions, the bottom of the partitions being in contact with the bottom wall of the groove, and the two sides of the partitions being in contact with the side walls of the groove.

[0012] In one or more embodiments of the present invention, the surface of the nanoimprint mold and the inner wall of the through hole are covered with an anti-adhesion film.

[0013] In one or more embodiments of the present invention, the anti-adhesion material of the anti-adhesion film includes one of perfluorooctyltrichlorosilane, polytetrafluoroethylene, and perfluorodecyltrichlorosilane; and / or,

[0014] The thickness of the anti-adhesion film ranges from 4 nm to 16 nm.

[0015] In one or more embodiments of the present invention, a plurality of micro-control switches are provided at the through hole at the bottom of the groove, and the micro-control switches are used to control the opening or closing of the through hole.

[0016] Another specific embodiment of the present invention provides the following technical solution:

[0017] A method for preparing a nanoimprint mold, the method comprising:

[0018] A recessed groove is formed on the first surface of the substrate;

[0019] Microstructures protruding from the second surface of the substrate are prepared.

[0020] Multiple through holes are fabricated on the substrate, penetrating the bottom of the groove and the second surface, and the through holes are located beside the microstructure.

[0021] Another specific embodiment of the present invention provides the following technical solution:

[0022] A nanoimprinting method, the method comprising:

[0023] Provide substrates and nanoimprint molds;

[0024] The microstructure of the nanoimprint mold is aligned and pressed with the substrate, and adhesive is filled into the groove so that the adhesive fills the space between the substrate and the nanoimprint mold through the through-hole.

[0025] The adhesive is cured.

[0026] The nanoimprint mold is peeled off, and the target nanoimprint pattern is obtained on the substrate.

[0027] In one or more embodiments of the present invention, the method further includes: controlling the through hole to close via a micro-switch and filling the groove with adhesive;

[0028] The via is controlled by a micro-switch to allow the adhesive to fill the space between the substrate and the nanoimprint mold through the via.

[0029] Compared with the prior art, the nanoimprint mold, preparation method and nanoimprint method of the present invention, by setting through holes on the side of the microstructure, prevent the formation of residual imprint adhesive layer between the microstructure and the substrate, so that no subsequent processing procedures are required, greatly reducing the processing steps and difficulty, and improving the fidelity and quality of the target nanopattern.

[0030] By setting partitions in the grooves to precisely control the amount of adhesive, the adhesive can be evenly distributed in each sub-groove, ensuring the consistency and accuracy of nanoimprinting and improving imprinting efficiency.

[0031] By setting an anti-adhesion film on the surface of the nanoimprint mold and the inner wall of the through hole, adhesive residue is avoided, thus improving the quality of nanoimprinting. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 is a cross-sectional schematic diagram of a nanoimprint mold in Embodiment 1 of the present invention;

[0034] Figure 2 is a schematic diagram of the second surface of a nanoimprint mold in Embodiment 1 of the present invention;

[0035] Figure 3 is a schematic diagram of the groove of a nanoimprint mold in Embodiment 1 of the present invention;

[0036] Figure 4 is a schematic diagram of the groove of another nanoimprint mold in Embodiment 1 of the present invention;

[0037] Figure 5 is a cross-sectional schematic diagram of another nanoimprint mold in Embodiment 1 of the present invention;

[0038] Figure 6 is a flowchart of the preparation method of the nanoimprint mold in Embodiment 2 of the present invention;

[0039] Figure 7 is a flowchart of the preparation method of the nanoimprint mold in Embodiment 2 of the present invention;

[0040] Figure 8 is a flowchart of the preparation method of the nanoimprint mold in Embodiment 2 of the present invention;

[0041] Figure 9 is a flowchart of the nanoimprinting method in Embodiment 3 of the present invention;

[0042] Figure 10 is a flowchart of the nanoimprinting method in Embodiment 3 of the present invention;

[0043] Figure 11 is a schematic diagram of the target nanoimprint pattern in Embodiment 3 of the present invention. Detailed Implementation

[0044] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0045] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0046] The terms "coupled," "connected," or "linked" in this specification include both direct and indirect connections. An indirect connection is a connection made through an intermediate medium, such as an electrical conduction medium, which may have parasitic inductance or capacitance. Indirect connections may also include connections made through other active or passive devices to achieve the same or similar functional purpose, such as connections through switches, follower circuits, or other circuits or components. Furthermore, in this invention, terms such as "first" and "second" are primarily used to distinguish one technical feature from another, and do not necessarily require or imply any actual relationship, quantity, or order between these technical features.

[0047] In the detailed description of this specification, reference is made to the accompanying drawings, which form a part thereof, wherein like reference numerals always denote like parts, and wherein exemplary embodiments are shown by way of example that may be implemented. It should be understood that other embodiments may be utilized, and structural or logical changes may be made, without departing from the scope of this disclosure. Therefore, the following detailed description should not be considered limiting.

[0048] The various operations in the specification may be described sequentially as multiple discrete actions or operations in a manner most conducive to understanding the claimed subject matter. However, the order of description should not be construed as implying that these operations must be sequentially related. Specifically, these operations may not be performed in the order presented. The described operations may be performed in a different order than in the described embodiments. Various additional operations may be performed in additional embodiments and / or the described operations may be omitted.

[0049] The description uses the phrases "in this embodiment," "in other embodiments," or "in some embodiments," each of which may refer to one or more of the same or different embodiments. Furthermore, the terms "comprising," "including," "having," etc., used with respect to embodiments of this disclosure are synonymous. Example 1:

[0050] As shown in Figures 1 and 2, this embodiment provides a nanoimprint mold, which includes a substrate 10. The substrate 10 has a first surface 11 and a second surface 12 disposed opposite to each other. A microstructure 30 protruding from the second surface 12 is formed on the second surface 12 of the substrate 10. A recessed groove 20 is formed on the first surface 11 of the substrate. The substrate is also provided with a plurality of through holes 40 penetrating the bottom of the groove 20 and the second surface 12. The through holes are located beside the microstructure 30.

[0051] The microstructures 30 are spaced apart, and the through holes 40 are spaced apart, with the size of the through holes 40 being less than or equal to the size of the microstructures 30. In this embodiment, "size" can be understood as diameter or width.

[0052] As shown in Figure 2, in one embodiment, the microstructure 30 is a columnar microstructure, which is arranged in an array with intervals. The size of the columnar microstructure 30 (i.e., the cross-sectional diameter of the columnar microstructure 30) is 1 μm to 1000 μm. The through-hole 40 is a circular through-hole, which is also arranged in an array with intervals. The size of the circular through-hole 40 (i.e., the diameter of the circular through-hole 40) is 0.8 to 1 times the size of the columnar microstructure, that is, the size of the circular through-hole 40 (i.e., the diameter of the circular through-hole 40) is 0.8 μm to 1000 μm.

[0053] In one embodiment, the depth of the groove 20 is greater than or equal to the height of the microstructure 30. It is understood that the groove 20 is used to contain the adhesive. By controlling the depth of the groove 20 to be greater than or equal to the height of the microstructure 30, it can be ensured that a sufficient amount of adhesive is injected into the groove 20 at one time.

[0054] As shown in Figure 3, in one embodiment, the nanoimprint mold is provided with a groove 20, and the size of the groove 20 can cover all microstructures 30.

[0055] As shown in Figure 4, in another embodiment, the groove 20 is provided with a partition 21. The bottom of the partition 21 contacts the bottom wall of the groove 20, and the two sides of the partition 21 contact the side walls of the groove 20 respectively. The partition 21 divides the groove 20 into multiple non-interconnected sub-grooves, such as the first sub-grooves 211 and the second sub-grooves 212. By setting the partition 21, the amount of adhesive can be more precisely controlled, and the adhesive can be more easily and evenly distributed in each sub-groove, ensuring the consistency and accuracy of nanoimprinting and improving imprinting efficiency.

[0056] Furthermore, the surfaces of the nanoimprint mold (including the surface of the microstructure 30, the first surface 11, the second surface 12, and the inner surface of the groove 20) and the inner walls of the through-hole 40 are covered with an anti-adhesion film. The anti-adhesion film prevents adhesive from remaining on the surface of the nanoimprint mold and the inner walls of the through-hole 40. The anti-adhesion material of the anti-adhesion film includes one of perfluorooctyltrichlorosilane, polytetrafluoroethylene, and perfluorodecyltrichlorosilane. Preferably, the thickness of the anti-adhesion film ranges from 4 nm to 16 nm.

[0057] In this embodiment, the material of the nanoimprint mold includes silicon.

[0058] As shown in Figure 5, in one embodiment, a plurality of micro-switches 50 are provided at the through-hole 40 at the bottom of the groove 20. The micro-switches 50 are used to control the opening or closing of the through-hole 40. In a first state, the micro-switches 50 cover the through-hole 40 to close it. In a second state, the micro-switches 50 open to open the through-hole 40. Optionally, the micro-switches 50 are MEMS (Micro Electro Mechanical Systems) switches.

[0059] When nanoimprinting is performed using the nanoimprint mold proposed in this embodiment in conjunction with the substrate, no residual imprinting adhesive layer will be formed between the microstructure 30 and the substrate. Therefore, no subsequent processing procedures are required (such as adding a reactive ion beam etching process to remove the residual imprinting adhesive layer), which greatly reduces the processing steps and difficulty and improves the fidelity of the target nanostructure. Example 2:

[0060] As shown in Figures 6 and 7, this embodiment provides a method for preparing a nanoimprint mold, the method comprising:

[0061] S11, a recessed groove 20 is formed on the first surface 11 of the substrate. In this embodiment, the substrate material is silicon, and the groove 20 is obtained on the first surface 11 of the substrate by etching or corrosion.

[0062] S12, a microstructure 30 protruding from the second surface 12 is prepared on the second surface 12 of the substrate.

[0063] S13, a plurality of through holes 40 penetrating the bottom of the groove 20 and the second surface 12 are formed on the substrate 10, and the through holes 40 are located beside the microstructure 30. Preferably, the through holes 40 are laser etched.

[0064] Furthermore, the preparation method in this embodiment also includes: preparing an anti-adhesion film on the surface of the nanoimprint mold and the inner wall of the through hole 40. Specifically, under vacuum conditions, the anti-adhesion material (one of perfluorooctyltrichlorosilane, polytetrafluoroethylene, and perfluorodecyltrichlorosilane) is evaporated by heating and vaporized, and the anti-adhesion material particles fly to the surface of the nanoimprint mold and the inner wall of the through hole 40 and condense into an anti-adhesion film.

[0065] As shown in Figure 8, further, the fabrication method in this embodiment also includes: setting a plurality of micro-control switches 50 at the through hole 40 at the bottom of the groove 20, the micro-control switches 50 being used to control the conduction or deactivation of the through hole 40. Optionally, the micro-control switches 50 are MEMS (Micro Electro Mechanical Systems) switches. Example 3:

[0066] As shown in Figures 9 and 10, this embodiment provides a nanoimprinting method, the method comprising:

[0067] S21 provides a substrate 60 and a nanoimprint mold.

[0068] S22, the microstructure 30 of the nanoimprint mold is aligned and pressed with the substrate 60, and adhesive is filled into the groove 20 so that the adhesive fills the space between the substrate 60 and the nanoimprint mold through the through hole 40. When aligning and pressing the microstructure 30 with the substrate 60, a certain pressure is applied to ensure that the substrate 60 and the nanoimprint mold are completely adhered.

[0069] S23, Curing the adhesive, for example, by using ultraviolet light.

[0070] S24, peel off the nanoimprint mold and obtain the target nanoimprint pattern 70 on the substrate 60.

[0071] As shown in Figure 10, the method further includes: controlling the through hole to be closed by micro-control switch 50, and filling the groove 20 with adhesive liquid;

[0072] The micro-switch 50 controls the through-hole to open, so that the adhesive liquid can fill the space between the substrate 60 and the nanoimprint mold through the through-hole 40.

[0073] The via is turned off by a microswitch 50. Optionally, the microswitch 50 is a MEMS (Micro Electro Mechanical Systems) switch.

[0074] As shown in Figure 10, the target nanoimprint pattern is obtained based on the nanoimprint mold shown in Figure 2. No residual imprint adhesive layer is formed between the microstructure 30 and the substrate, so no subsequent processing procedures are required (e.g., adding a reactive ion beam etching process to remove the residual imprint adhesive layer), which greatly reduces the processing steps and difficulty and improves the fidelity of the target nanostructure.

[0075] As can be seen from the above technical solutions, the present invention has the following beneficial effects:

[0076] By setting through-holes 40 and microstructures 30, the present invention ensures that no residual imprinting adhesive layer is formed between the microstructures 30 and the substrate 60. Therefore, no subsequent processing procedures are required (such as adding a reactive ion beam etching process to remove the residual imprinting adhesive layer), which greatly reduces the processing steps and difficulty and improves the fidelity and quality of the target nanopattern.

[0077] By setting a separator 21 in the groove 20 to precisely control the amount of adhesive, the adhesive can be evenly distributed in the groove, ensuring the consistency and accuracy of nanoimprinting and improving the imprinting efficiency.

[0078] By setting an anti-adhesion film on the surface of the nanoimprint mold and the inner wall of the through hole 40, adhesive residue is avoided, thus improving the quality of nanoimprinting.

[0079] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0080] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A nanoimprint mold, characterized in that, The nanoimprint mold includes a substrate, which has a first surface and a second surface disposed opposite to each other. A microstructure protruding from the second surface is formed on the second surface of the substrate, and a recessed groove is formed on the first surface of the substrate. The substrate is also provided with a plurality of through holes penetrating the bottom of the groove and the second surface, and the through holes are located beside the microstructure.

2. The nanoimprint mold according to claim 1, characterized in that, The microstructures are spaced apart, the through-holes are spaced apart, and the size of the through-holes is less than or equal to the size of the microstructures; and / or, The microstructure is a columnar microstructure, which is arranged in an array with intervals. The size of the columnar microstructure is 1μm to 1000μm. The through-hole is a circular through-hole, which is arranged in an array with intervals. The size of the circular through-hole is 0.8μm to 1000μm, and the size of the circular through-hole is less than or equal to the size of the columnar microstructure.

3. The nanoimprint mold according to claim 1, characterized in that, The depth of the groove is greater than or equal to the height of the microstructure.

4. The nanoimprint mold according to claim 1, characterized in that, The groove is provided with several partitions, the bottom of which is in contact with the bottom wall of the groove, and the two sides of which are in contact with the side walls of the groove.

5. The nanoimprint mold according to claim 1, characterized in that, The surface of the nanoimprint mold and the inner wall of the through hole are covered with an anti-adhesion film.

6. The nanoimprint mold according to claim 5, characterized in that, The anti-adhesion material of the anti-adhesion film includes one of perfluorooctyltrichlorosilane, polytetrafluoroethylene, and perfluorodecyltrichlorosilane; and / or, The thickness of the anti-adhesion film ranges from 4 nm to 16 nm.

7. The nanoimprint mold according to claim 1, characterized in that, Multiple micro-switches are provided at the through hole at the bottom of the groove. The micro-switches are used to control the opening or closing of the through hole.

8. A method for preparing a nanoimprint mold, characterized in that, The method includes: A recessed groove is formed on the first surface of the substrate; Microstructures protruding from the second surface of the substrate are prepared. Multiple through holes are fabricated on the substrate, penetrating the bottom of the groove and the second surface, and the through holes are located beside the microstructure.

9. A nanoimprinting method, characterized in that, The method includes: Provide a substrate and a nanoimprint mold as described in any one of claims 1 to 7; The microstructure of the nanoimprint mold is aligned and pressed with the substrate, and adhesive is filled into the groove so that the adhesive fills the space between the substrate and the nanoimprint mold through the through-hole. The adhesive is cured. The nanoimprint mold is peeled off, and the target nanoimprint pattern is obtained on the substrate.

10. The nanoimprinting method according to claim 9, characterized in that, The method further includes: The through hole is shut off by a micro-switch, and adhesive is filled into the groove. The via is controlled by a micro-switch to allow the adhesive to fill the space between the substrate and the nanoimprint mold through the via.

Images