Method for forming nano-pattern structure on substrate

Abstract

The invention discloses a method for forming a nanometer pattern structure on a substrate, which comprises the following steps: dividing an imprinting mother board into a plurality of areas according to the distribution of the nanometer pattern structure on the imprinting mother board, each area having the nanometer pattern structure with the same depth; carrying out corresponding region division on the substrate according to the region division condition of the imprinting mother board; pre-etching the substrate after region division by using an etching process, so that the thicknesses of the substrate in different regions are differentially adjusted according to the depth of the nano pattern in the corresponding imprinting mother board region; spin-coating an imprint adhesive on the pre-etched substrate; the nanometer pattern structure on the imprinting mother board is transferred to the imprinting glue through the imprinting technology, so that the thicknesses of imprinting glue residual layers in all the areas are consistent; and etching the impressed substrate, and transferring the imprint glue pattern to the substrate to form a nano pattern structure consistent with the imprint mother board. According to the invention, the thickness difference of the residual layer can be actively compensated, and the etching consistency of each region of the nano pattern structure is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of nanoimprinting, and particularly relates to a method for forming a nano-patterned structure on a substrate. Background Art

[0002] In the high-precision manufacturing fields such as optics and semiconductors, the nanoimprint process, as a key technology capable of realizing the replication of nano-scale structures, has been widely applied. This process mainly replicates the nano-patterned structure on a master plate onto a substrate coated with an imprinting resin, prepares a low-residual layer resin sample, and then combines with an etching process to transfer the resin layer structure onto the substrate, thereby forming the required nano-patterned structure on the substrate.

[0003] However, in practical applications, the imprint master plate usually has a variety of different nano-patterned structures, and these structures will cause a certain fluidity of the imprinting resin during the imprinting process. Due to the differences in the master plate structures in different regions, the filled resin volumes are different, resulting in inconsistent residual layer thicknesses in different regions, and it is difficult to ensure that the residual layer thicknesses in different structural regions of the resin are exactly the same. In the subsequent etching process, the region with a thinner residual layer will be etched away earlier than the region with a thicker residual layer. Also, because the etching rates of the substrate and the imprinting resin are different, when continuing the etching, the morphological reduction structures in different regions will deviate, ultimately resulting in the inability of the structure and depth of the substrate to be consistent with the master plate, seriously affecting the pattern transfer accuracy after etching.

[0004] For example, as Figure 1 shown, in the region with a denser structure (Region 1) of the imprint master plate, the residual layer may be thicker (d1) due to insufficient filling of the imprinting resin, while in the region with a sparser structure (Region 2), the residual layer is thinner (d2, d2 > d1). In the subsequent etching process, due to the difference in residual layer thickness and the mismatch between the etching rates of the substrate material and the imprinting resin, the region with a thinner residual layer will be etched first, resulting in over-etching of the substrate after exposure, and ultimately causing a deviation in the depth of the transferred structure from the original structure of the master plate. Specifically, the substrate structure in Region 2 is over-etched due to premature exposure, and the depth exceeds the design value; while in Region 1, due to the thicker residual layer, the etching time is insufficient, resulting in insufficient structure depth. This problem of pattern transfer distortion caused by uneven residual layer thickness seriously restricts the fabrication accuracy of complex multi-structure devices, especially in scenarios that require high-fidelity structure replication, such as optical diffraction elements or three-dimensional integrated chips. Existing solutions usually improve the filling uniformity by optimizing the imprinting resin material or adjusting the imprinting pressure, but such methods are difficult to fundamentally eliminate the residual layer thickness difference caused by the diversity of the master plate structure and are easily affected by process parameter fluctuations. Summary of the Invention

[0005] To solve the above technical problems, the present invention proposes a method for forming a nano-patterned structure on a substrate.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] The present invention discloses a method for forming a nano-patterned structure on a substrate, comprising:

[0008] Step S1: According to the distribution of the nano-patterned structure on the imprint master, divide it into several regions, and each region has a nano-patterned structure with the same depth;

[0009] Step S2: According to the regional division of the imprint master, divide the substrate into corresponding regions;

[0010] Step S3: Use an etching process to pre-etch the substrate after regional division, so that the thickness of the substrate in different regions is differentially adjusted according to the depth of the nano-pattern in the corresponding region of the imprint master;

[0011] Step S4: Spin-coat an imprint resist on the pre-etched substrate;

[0012] Step S6: Transfer the nano-patterned structure on the imprint master to the imprint resist through an imprint process, so that the thickness of the residual layer of the imprint resist in each region is consistent;

[0013] Step S7: Etch the imprinted substrate to transfer the imprint resist pattern to the substrate and form a nano-patterned structure consistent with the imprint master.

[0014] Based on the above technical solution, the following improvements can also be made:

[0015] As a preferred solution, in step S1, the imprint master is divided into regions based on one or more of the shape, density, depth, and topological structure of the nano-patterned structure.

[0016] As a preferred solution, in step S3, the depth of pre-etching of any region of the substrate has a positive correlation with the depth of the nano-pattern in the corresponding region of the imprint master.

[0017] As a preferred solution, in step S3, the depth of pre-etching is determined according to the depth of the nano-patterned structure in the corresponding region of the imprint master and the fluidity of the imprint resist.

[0018] As a preferred solution, the pre-etching in step S3 adopts a dry etching or wet etching process.

[0019] As a preferred solution, step S3 includes:

[0020] Step S3.1: Form a photoresist layer on the surface of the substrate, and perform photolithography using a mask plate corresponding to the regional division of the imprint master to form a patterned photoresist mask;

[0021] Step S3.2: Develop the substrate after lithography to remove the photoresist in some areas to expose the substrate;

[0022] Step S3.3: Selectively remove the exposed substrate area through an etching process to form a substrate with different regional thicknesses.

[0023] As a preferred solution, in Step S4, after spin coating, the upper surface of the imprinting resist is horizontal, and the thickness of each area of the imprinting resist is determined according to the thickness of different areas of the substrate after pre-etching.

[0024] As a preferred solution, between Step S4 and Step S6, it further includes:

[0025] Step S5: Align the imprinting master with the substrate coated with the imprinting resist so that each divided area of the master matches the corresponding area of the substrate in position.

[0026] As a preferred solution, in Step S6, the pressure and temperature of the imprinting process are adjusted according to the material of the imprinting master and the characteristics of the imprinting resist.

[0027] As a preferred solution, after Step S6 and before Step S7, it further includes the step of detecting and repairing the nano-pattern structure on the imprinting resist.

[0028] The present invention discloses a method for forming a nano-pattern structure on a substrate, which has the following beneficial effects:

[0029] The present invention performs pre-etching treatment on the substrate to be imprinted. By regulating the thickness of different areas on the substrate to match different structural areas on the template, the height of the final imprinting residual layer is made consistent, thereby improving the pattern transfer accuracy.

[0030] The present invention can actively compensate for the thickness difference of the residual layer and improve the consistency of etching in each area of the nano-pattern structure. Description of the Drawings

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0032] Figure 1 It is a preparation diagram for forming a nano-pattern structure on a substrate provided by the prior art.

[0033] Figure 2 It is a flowchart for forming a nano-pattern structure on a substrate provided by an embodiment of the present invention

[0034] Figure 3 Preparation diagram for forming a nano-pattern structure on a substrate provided by an embodiment of the present invention.

[0035] Figure 4 Preparation diagram for pre-etching provided by an embodiment of the present invention. Detailed implementation manners

[0036] The preferred implementation manners of the present invention will be described in detail below with reference to the accompanying drawings.

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0038] The expression "including" an element is an "open-ended" expression, which only means that there are corresponding components or steps, and should not be interpreted as excluding additional components or steps.

[0039] In order to achieve the object of the present invention, in some embodiments of the method for forming a nano-pattern structure on a substrate, as Figure 2-3 shown, the method includes:

[0040] Step S101: According to the distribution of the nano-pattern structure on the imprint master, it is divided into several regions (such as: Region 1 and Region 2), and each region has a nano-pattern structure with the same depth;

[0041] Step S102: According to the region division of the imprint master, the substrate is also divided into corresponding regions;

[0042] Step S103: Use an etching process to pre-etch the substrate after region division, so that the thickness of the substrate in different regions is differentially adjusted according to the nano-pattern depth of the corresponding region of the imprint master;

[0043] Step S104: Spin-coat an imprint resist on the pre-etched substrate;

[0044] Step S105: Align the regions of the imprint master with the substrate coated with the imprint resist, so that the divided regions of the master match the corresponding regions of the substrate in position;

[0045] Step S106: Transfer the nano-pattern structure on the imprint master to the imprint resist after configuration registration through an imprint process, so that the thickness of the residual layer of the imprint resist in each region is the same (the thickness of the residual layers in Region 1 and Region 2 is both d);

[0046] Step S107: Etch the imprinted substrate to transfer the imprinted resist pattern to the substrate, forming a nano-pattern structure identical to the imprint master.

[0047] It should be noted that the above substrate can be: semiconductor materials, polymer materials, metal materials, etc.

[0048] In the above step S101, the imprint master can be, but is not limited to, divided into regions based on one or more of the shape, density, depth, and topology of the nano-pattern structure.

[0049] To further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that in step S103, the pre-etching depth of any region of the substrate is positively correlated with the depth of the nano-pattern in the corresponding region on the imprint master.

[0050] To further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that in step S103, the pre-etching depth is determined according to the depth of the nano-pattern structure in the corresponding region of the imprint master and the fluidity of the imprint resist.

[0051] To further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that in step S103, the pre-etching is performed using a dry etching or wet etching process.

[0052] To further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that as Figure 4 shown, step S103 includes:

[0053] Step S103.1: Form a photoresist layer on the surface of the substrate, and perform photolithography using a mask plate corresponding to the region division of the imprint master to form a patterned photoresist mask;

[0054] Step S103.2: Develop the substrate after photolithography to remove the photoresist in some regions to expose the substrate;

[0055] Step S103.3: Selectively remove the exposed substrate regions through an etching process to form a substrate with different regional thicknesses.

[0056] To further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that in step S104, after spin coating, the upper surface of the imprint resist is horizontal, and the thickness of each region of the imprint resist is determined according to the thickness of different regions of the substrate after pre-etching.

[0057] In order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that in step S106, the pressure and temperature of the imprinting process are adjusted according to the material of the imprinting master and the characteristics of the imprinting glue.

[0058] In order to further optimize the implementation effect of the present invention, in some other embodiments, the remaining characteristic technologies are the same, except that after step S6 and before step S7, there is also a step of detecting and repairing the nano-pattern structure on the imprinting glue.

[0059] The present invention discloses a method for forming a nano-pattern structure on a substrate, which has the following beneficial effects:

[0060] The present invention performs pre-etching treatment on the substrate to be imprinted. By regulating the thickness of different regions on the substrate to match different structural regions on the template, the height of the final imprinting residual layer is made consistent, thereby improving the pattern transfer accuracy.

[0061] The present invention can actively compensate for the thickness difference of the residual layer and improve the etching consistency of each region of the nano-pattern structure.

[0062] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inner", "front", "center", "both ends", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0063] In the present invention, unless otherwise clearly defined and limited, the terms "installed", "set", "connected", "fixed", "swivelly connected", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. It can be the internal communication of two elements or the interaction relationship between two elements. Unless otherwise clearly limited, for those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0064] The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A method for forming a nano-patterned structure on a substrate, characterized in that, Including: Step S1: According to the distribution of the nano-pattern structure on the imprint master, divide it into several regions, and each region has a nano-pattern structure with the same depth; Step S2: According to the regional division of the imprint master, divide the substrate correspondingly; Step S3: Use an etching process to pre-etch the substrate after regional division, so that the thickness of the substrate in different regions is differentially adjusted according to the depth of the nano-pattern in the corresponding region of the imprint master; Step S4: Spin-coat an imprint resist on the pre-etched substrate; Step S6: Transfer the nano-pattern structure on the imprint master to the imprint resist through an imprint process, so that the thickness of the residual layer of the imprint resist in each region is consistent; Step S7: Etch the imprinted substrate to transfer the imprint resist pattern to the substrate, forming a nano-pattern structure consistent with the imprint master.

2. The method according to claim 1, wherein In the said Step S1, the imprint master is regionally divided based on one or more of the shape, density, depth, and topological structure of the nano-pattern structure.

3. The method according to claim 1, wherein In the said Step S3, the depth of pre-etching in any region of the substrate is positively correlated with the depth of the nano-pattern in the corresponding region on the imprint master.

4. The method according to claim 1, characterized in that, In the said Step S3, the depth of pre-etching is determined according to the depth of the nano-pattern structure in the corresponding region of the imprint master and the fluidity of the imprint resist.

5. The method according to claim 1, characterized in that, The pre-etching in the said Step S3 adopts a dry etching or wet etching process.

6. The method according to claim 1, wherein The said Step S3 includes: Step S3.1: Form a photoresist layer on the surface of the substrate, and perform photolithography using a mask plate corresponding to the regional division of the imprint master to form a patterned photoresist mask; Step S3.2: Develop the substrate after photolithography to remove the photoresist in some regions to expose the substrate; Step S3.3: Selectively remove the exposed substrate region through an etching process to form a substrate with different regional thicknesses.

7. The method according to claim 1, wherein In the said Step S4, after spin-coating, the upper surface of the imprint resist is horizontal, and the thickness of the imprint resist in each region is determined according to the thickness of different regions of the substrate after pre-etching.

8. The method according to claim 1, wherein Between the said Step S4 and Step S6, there is also included: Step S5: Align the regions of the imprint master and the substrate coated with the imprint resist, so that the divided regions of the master match the corresponding regions of the substrate in position.

9. The method according to claim 1, characterized in that, In the said Step S6, the pressure and temperature of the imprint process are adjusted according to the material of the imprint master and the characteristics of the imprint resist.

10. The method according to claim 1, characterized in that, After Step S6 and before Step S7, there is also included a step of detecting and repairing the nano-pattern structure on the imprint resist.

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