KR102669493B1 - 3D microstructure replication method using Poisson effect - Google Patents

Abstract

The present invention relates to a 3D microstructure replication method using the Poisson effect. According to the present invention, a soft mold preparation step of forming a soft mold by transferring a superelastic material to a master mold using a soft lithography method, the above A resin application step of applying resin to a soft mold, a compression step of applying vertical pressure to the upper surface of the soft mold and deforming the shape of the soft mold using the Poisson effect caused by the vertical pressure, and applying heat to the soft mold whose shape has been deformed. Or a resin curing step of curing the resin by applying ultraviolet rays to create the 3D microstructure and a release step of restoring the shape of the soft mold by removing vertical pressure on the soft mold and releasing the 3D microstructure. A 3D microstructure replication method using the Poisson effect can be provided.

Description

3D microstructure replication method using Poisson effect}

The present invention relates to a 3D microstructure replication method using the Poisson effect. More specifically, in the process of replicating a 3D microstructure, it is possible to mass-produce a 3D microstructure by repeatedly replicating the same type of microstructure using the same method. This relates to a 3D microstructure replication method using the Poisson effect.

Generally, in order to manufacture a three-dimensional structure, a mold that can create the shape of the three-dimensional structure must be manufactured.

To achieve this, a wooden mold is manufactured, and through a number of processes, a final mold is made to produce a three-dimensional structure.

At this time, a rapid prototyping process can be used to create a mold for a three-dimensional structure.

Here, the rapid prototyping process refers to forming a 3D prototype directly from 3D CAD data without a mold using materials such as paper, wax, ABS, and plastic.

In the field of such rapid forming processes, Korean Patent Publication No. 10-2000-0054896, 'Method and device for producing 3D prototypes using electric roller welding of thin metal plates' has been disclosed.

In the prior art, a prototype of a desired shape can be made by manufacturing a shaped part on a thin metal plate, stacking the thin metal plates on which the shaped part is formed, and welding the thin metal plates to each other with a welding roller.

However, in the manufacturing method of a three-dimensional structure such as the prior art, there is a limit to reducing the thickness of the metal sheet, and when the metal sheet is formed small to a thickness of several nanometers to tens of nanometers, the metal sheet must be wound on a roller. Difficult problems may arise.

In addition, the replication of structures for fine three-dimensional structures was extremely limited, and productivity was low, making mass production of three-dimensional structures difficult.

Therefore, there is a need to develop a microstructure replication method that can be mass-produced by manufacturing three-dimensional microstructures and reducing the number of steps and complexity of the work.

In order to solve the above problems, the present invention is a method of replicating 3D microstructures using the Poisson effect. The purpose of the present invention is to provide efficient and precise replication and mass production technology for 3D microstructures by reducing the number of work processes and complexity.

The 3D microstructure replication method using the Poisson effect according to an embodiment of the present invention to solve the above problem involves a soft mold preparation step of forming a soft mold by transferring a superelastic material to the master mold using a soft lithography method. , a resin application step of applying resin to the soft mold, a compression step of applying vertical pressure to the upper surface of the soft mold and deforming the shape of the soft mold using the Poisson effect caused by the vertical pressure, and the soft mold whose shape is deformed. a resin curing step of curing the resin by applying heat or ultraviolet rays to create the 3D microstructure; and a release step of restoring the shape of the soft mold by removing vertical pressure on the soft mold and releasing the 3D microstructure. It can be included.

Additionally, the soft mold preparation step may include a partition wall formed in a shape that becomes narrower as the master mold moves upward, and a protruding protrusion formed on an outer surface of the partition wall.

Additionally, in the soft mold preparation step, the soft mold may include a space formed by the partition wall and a resin cavity, which is a space formed by the protruding protrusion.

In addition, in the compression step, the separation space is narrowed due to the Poisson effect and the resin cavities located adjacent to each other around the separation space become connected, thereby forming the 3D microstructure.

In addition, the compression step calculates the vertical strain according to the change in the current width of the separation space through the following [Equation 1], selects a target vertical strain value, and transforms the shape of the soft mold up to the target vertical strain. You can do it.

[Equation 1]

(here, is the current width of the separation space, is the initial width of the separation space, is the width between the space facing the space, is the vertical strain, is Poisson's ratio.)

The 3D microstructure replication method using the Poisson effect according to the embodiment of the present invention as described above can replicate the microstructure of a 3D structure with a width in ㎛ units by inducing a shape deformation of the mold due to the Poisson effect.

Additionally, the number of steps and complexity of work can be reduced by using a soft mold that can apply the Poisson effect.

In addition, 3D microstructures of the same shape can be mass-produced with high accuracy through large-area, continuous production.

Figure 1 is a flowchart schematically showing a 3D microstructure replication method using the Poisson effect according to an embodiment of the present invention.
FIG. 2 is an exemplary diagram showing the master mold of FIG. 1.
Figure 3 is an exemplary diagram showing the soft mold of Figure 1.
Figures 4 (a) to (c) are longitudinal cross-sectional views of Figure 3, and are exemplary views showing the order in which the shape of the soft mold is deformed through the compression step.
Figure 5 (a) is a 3D microstructure replicated when the compression step of Figure 1 is not performed, (b) is a 3D microstructure replicated when the compression step is performed, and (c) is an enlarged 3D microstructure of (b). This is a photo showing the structure.
Figure 6 (a) is a 3D microstructure of a different form from Figure 5 (a), (b) is a 3D microstructure of a different form from Figure 5 (b), and (c) is a different form from Figure 5 (c). This is a photo showing a different type of 3D microstructure.
Figure 7 (a) is an example diagram showing a 3D microstructure target pattern to be copied, and (b) and (c) are photographs showing a 3D microstructure replicated in the form (a) of Figure 1.
Figure 8 (a) is an example diagram showing a 3D microstructure target pattern of a different form from Figure 7 (a), and Figures 8 (b) and (c) are duplicates of the form of Figure 8 (a). This is a photo showing the 3D microstructure.
Figures 9 (a) to (d) are photographs showing 3D microstructures replicated in Figure 1 at different vertical strain rates.

Since the present invention can make various changes and take various forms, specific embodiments will be described in detail in the text. However, this is not intended to limit the present invention to a specific disclosed form, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the existence of a combination of features, numbers, steps, components, etc. described in the specification, but are not limited to one or more other features or numbers, It should be understood that the existence or addition possibility of combinations of steps, components, etc. is not excluded in advance.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless clearly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

Here, repeated descriptions, known functions that may unnecessarily obscure the gist of the present invention, and detailed descriptions of configurations are omitted. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 9.

Figure 1 is a flowchart schematically showing a 3D microstructure replication method using the Poisson effect according to an embodiment of the present invention, Figure 2 is an exemplary diagram showing the master mold of Figure 1, and Figure 3 is a soft mold of Figure 1. is an example diagram showing, and Figures 4 (a) to (c) are longitudinal cross-sectional views of Figure 3 and are examples showing the order in which the soft mold is deformed through the compression step, and Figure 5 (a) is a 3D microstructure that is replicated when the compression step of Figure 1 is not performed, (b) is a 3D microstructure that is duplicated when the compression step is performed, (c) is a photograph showing an enlarged 3D microstructure of (b), Figure 6 (a) is a 3D microstructure of a different form from Figure 5 (a), (b) is a 3D microstructure of a different form from Figure 5 (b), and (c) is a different form from Figure 5 (c). This is a photograph showing a different type of 3D microstructure. Figure 7 (a) is an example showing a 3D microstructure target pattern to be copied, and (b) and (c) are replicated in the form of (a) in Figure 1. It is a photograph showing a 3D microstructure, and Figure 8 (a) is an example diagram showing a 3D fine structure target pattern of a different form from Figure 7 (a), and Figures 8 (b) and (c) are Figure 8 It is a photograph showing a 3D microstructure replicated in the form of (a), and Figures 9 (a) to (d) are photographs showing a 3D microstructure replicated at different vertical strain rates as shown in Figure 1.

Referring to Figure 1, the 3D microstructure replication method using the Poisson effect according to an embodiment of the present invention is a method of replicating a 3D microstructure with a width in ㎛ units, and includes a soft mold preparation step (S10) and a resin application step ( It may include a compression step (S30), a resin curing step (S40), and a release step (S50).

First, the soft mold preparation step (S10) is a step of forming the soft mold 20 by transferring a superelastic material to the master mold 10 using a soft lithography method.

Here, referring to FIG. 2 , the master mold 10 may include a partition wall 11 formed in a shape that becomes narrower as it moves upward, and a protruding protrusion 12 formed on the outer surface of the partition wall 11.

Specifically, the master mold 10 uses two photons and a pulse laser to cause a chemical reaction by absorbing the two photons in the area where the pulse laser is focused, and outputs the object by layering the material generated by the chemical reaction. It can be produced using 2PP (2 Photon Polymerization), a 3D printing method.

Accordingly, the master mold 10 can be manufactured in detail.

Additionally, the partition wall 11 may have a width equal to or greater than the width of the 3D microstructure to be replicated.

Accordingly, the 3D microstructure can be stably released from the separation space 21 formed by the partition wall 11.

Additionally, the shape of the protruding protrusion 11 may vary depending on the shape of the 3D microstructure that the user wishes to replicate.

Specifically, the protruding protrusions 11 are a part of a 3D microstructure, and a plurality of protruding protrusions 11 can be gathered together to form one 3D microstructure.

For example, when replicating a 3D microstructure in the form of a half ring as shown in FIG. 2, the protruding protrusions 11 may be formed in a divided form so that the half ring is left and right symmetrical. .

Soft lithography is a transfer method that creates patterns or structures using flexible organic materials.

Specifically, soft lithography methods may include molding methods such as replica molding, capillary force lithography, capillary-micro-molding, micro-transfer molding, and liquid-mediated transfer molding.

Additionally, superelastic materials can be used as flexible inorganic materials.

Here, a superelastic material refers to a material that returns to its initial state when the load is removed, even if the object is deformed by approximately 500% or more.

Silicone, rubber, etc. may be used as such superelastic materials.

Accordingly, the soft mold 20 can return to its initial form even if its shape is deformed by vertical pressure (VP), allowing it to be reused, and the shape of a 3D microstructure can be manufactured consistently.

In addition, referring to FIG. 3, the soft mold 20 includes a space between the space 21 formed by the partition wall 11 and a resin cavity 22, which is a space formed by the protruding protrusion 12. You can do it.

Specifically, the separation space 21 may be formed in a shape where the lower side is open due to the partition wall 11 and becomes narrower as it moves toward the upper side.

Accordingly, the soft mold 20 may be provided with a space 21 where the Poisson effect (PE) can be applied.

Additionally, the resin cavity 22 may form a depressed space in the form of the protruding protrusion 12 due to the protruding protrusion 12 .

That is, the soft mold 20 may be formed as a reverse image of the master mold 10.

Next, the resin application step (S20) is a step of applying resin to the soft mold (20).

Specifically, the resin application step (S20) may apply resin to the separation space 21 and the resin cavity 22.

At this time, in the resin application step (S20), a sufficient amount of resin can be applied to the space 21 and the resin cavity 22 to form a 3D microstructure.

Additionally, in the resin application step (S20), thermosetting resin or ultraviolet curing resin can be used depending on the user's needs.

Next, the compression step (S30) is a step of applying vertical pressure (VP) to the upper surface of the soft mold 20 and deforming the shape of the soft mold 20 using the Poisson effect (PE) caused by the vertical pressure (VP). am.

At this time, in the compression step (S30), a substrate (not shown) may be placed on the upper and lower surfaces of the soft mold 20, and vertical pressure (VP) may be applied.

Here, glass, silicon wafer, film, etc. may be used as the substrate.

Accordingly, in the compression step (S30), the same intensity of vertical pressure (VP) can be applied to the entire area of the soft mold 20 with the substrate placed on the upper surface of the soft mold 20.

In addition, the compression step (S30) applies resin to the substrate applied to the lower surface of the soft mold 20, preventing shape deformation and wear that may occur due to friction with the soft mold 20 when the soft mold 20 is deformed. , heat, etc. problems can be reduced.

Additionally, the compression step (S30) may generate a Poisson effect (PE) in the soft mold 20 by applying vertical pressure (VP) to the soft mold 20.

Here, the Poisson effect (PE) is a property that when an object is compressed in one direction, it expands in a direction perpendicular to the compressed direction.

Accordingly, in the compression step (S30), vertical pressure (VP) is applied to the soft mold (20) to generate a force generated in the horizontal direction at a right angle to the vertical pressure (VP), thereby deforming the soft mold (20) to create a separation space. (21) can be narrowed down.

Specifically, referring to FIG. 4, (a) of FIG. 4 shows a cross-sectional state of the soft mold 20 to which the resin has been applied after the resin application step (S20).

Additionally, (b) in FIG. 4 shows a state in which vertical pressure (VP) is applied to the soft mold 20 in state (a).

At this time, it can be confirmed that the soft mold 20 receives an inward force from the space 21 due to the Poisson effect (PE).

In addition, (c) of FIG. 4 shows a state in which the vertical pressure (VP) is continuously applied and the separation space 21 is narrowed due to the Poisson effect (PE) in the state of (b).

Accordingly, it can be confirmed that the resin cavities 22 located adjacent to each other centered on the space 21 are in a communication state, and the applied resin is filled in the resin cavity 22 to form a 3D microstructure.

In addition, referring to (a) to (c) of FIGS. 5 and 6, (a) shows the shape of the 3D structure to be replicated when the compression step (S30) is not performed.

Here, it can be seen that the shapes of the separation space 21 and the resin cavity 22 are copied as is.

In addition, Figures 5 and 6 (b) show the shape of the 3D structure to be replicated when the compression step (S30) is performed.

Here, it can be seen that the shape of the space 21 is narrowed, and the resin cavities 22 located adjacent to the space 21 are connected to form a 3D microstructure.

Additionally, Figures 5 and 6 (c) show an enlarged version of the 3D structure in (b).

Here, it can be confirmed that the 3D microstructure is in communication with the resin cavity 22 and that the complete 3D microstructure is replicated.

In addition, the compression step (S30) calculates the vertical strain according to the change in the current width of the separation space through the following [Equation 1], selects the target vertical strain value, and compresses the soft mold 20 up to the target vertical strain. The shape can be changed.

[Equation 1]

here, is the current width of the separation space 21, is the initial width of the separation space 21, is the width between the space 21 and the space 21 facing each other, is the vertical strain, is Poisson's ratio.

In addition, Poisson's ratio represents the ratio of strain to the deformation of the soft mold 20, and can be calculated through the vertical strain at which the height of the soft mold 20 is changed and the horizontal strain at which the width of the soft mold 20 is changed. You can.

Specifically, Poisson's ratio can be calculated as '-horizontal strain / vertical strain'.

At this time, taking '-' to calculate Poisson's ratio means that when the horizontal strain becomes positive, the vertical strain becomes negative, and when the horizontal strain becomes negative, the vertical strain becomes positive, so the Poisson's ratio is calculated as a positive value. This is to do it.

At this time, the desired target vertical strain is The value of may be selected, that is, a value that makes the current width of the separation space 21 close to 0.

Additionally, the desired target normal strain may be selected to be a range of values that bring it close to zero.

Additionally, the vertical strain varies depending on the shape of the 3D microstructure the user wishes to replicate. The value may vary.

Accordingly, it is possible to manufacture a soft mold 20 capable of replicating the exact shape of the 3D microstructure by calculating the target vertical strain required to replicate the shape of the 3D microstructure that the user wishes to replicate.

Next, in the resin curing step (S40), a 3D microstructure can be created by curing the resin by applying heat or ultraviolet rays to the soft mold 20 whose shape has been deformed.

Specifically, in the resin curing step (S40), in the case of a thermosetting resin, heat may be applied to cure the thermosetting resin while the vertical pressure on the soft mold 20 is not removed.

Additionally, in the case of ultraviolet curable resin, the ultraviolet curable resin can be cured by applying ultraviolet rays.

More specifically, in the case of a thermosetting resin, the thermosetting resin can be cured at a temperature of 20°C or higher and 100°C or lower.

Specifically, thermosetting resin can be formed in various ways, depending on the type of thermosetting resin used, at a temperature for thermal curing within the range of 20°C or higher and 100°C or lower.

Here, in the resin curing step (S40), when cured at a temperature of less than 20℃, the thermosetting resin is not completely cured, and it may be difficult to maintain the shape of the 3D microstructure, and when cured at a temperature exceeding 100℃, Excessive hardening may cause shrinkage of the 3D microstructure.

In addition, in the case of ultraviolet curable resin, it can be cured by irradiating broadband ultraviolet rays at an intensity of 10 mW/cm ² or more and 1000 mW/cm ² or less for 1 minute or more and 10 minutes or less.

Specifically, the ultraviolet curable resin can be formed in various ways, with an appropriate amount of light for ultraviolet curing ranging from 10 mW/cm ² to 1000 mW/cm ² , depending on the type of ultraviolet curable resin used.

Here, in the resin curing step (S40), when the broadband ultraviolet ray is cured at an intensity of less than 10 mW/cm ² , the ultraviolet curable resin is not completely cured, so it may be difficult to maintain the shape of the 3D microstructure, and if the ultraviolet ray is cured at an intensity of less than 1000 mW/cm ² When cured at a strength of , excessive curing may occur and shrinkage of the 3D microstructure may occur.

In addition, in the resin curing step (S40), if broadband ultraviolet light is irradiated for less than 1 minute, the ultraviolet curable resin is not completely cured, and it may be difficult to maintain the shape of the 3D microstructure, and if irradiated for more than 10 minutes, it may already be damaged. In a sufficiently hardened state, it may cause inefficiency in work.

Next, the release step (S50) is a step of restoring the shape of the soft mold 20 by removing the vertical pressure on the soft mold 20 and releasing the 3D microstructure.

At this time, in the release step (S50), the width of the separation space 21 of the soft mold 20 is restored to its initial state where it is wider than the width of the 3D microstructure, and the 3D microstructure can be safely released.

Additionally, the release step (S50) may release a number of 3D microstructures depending on the shape of the soft mold 20.

As described above, the 3D microstructure replication method using the Poisson effect according to an embodiment of the present invention replicates the 3D microstructure using the Poisson effect (PE), thereby producing a 3D microstructure in a more precise form compared to existing microstructure replication. can be copied.

In addition, the number of processes and complexity of work can be reduced by using a soft mold 20 formed of a superelastic material capable of applying the Poisson effect (PE).

In addition, by reusing the soft mold 20, 3D microstructures of the same shape can be mass-produced with high accuracy through large-area, continuous production.

In addition, as shown in (a) of Figure 7, an array of 3D microstructures with high density compared to area can be produced by utilizing the 3D space as shown in (b) and (c) according to the target pattern of the 3D microstructure according to the user's request. .

In addition, as shown in (a) of FIG. 8, 3D microstructures with a connected ring-shaped target pattern, which were difficult to replicate with conventional technology, can be replicated as shown in (b) and (c).

As such, the 3D microstructure replication method using the Poisson effect according to an embodiment of the present invention can replicate 3D microstructures applied to a wide range of industrial fields such as building materials such as fine thin films and superhydrophobic surfaces, electronic components, and cosmetics. there is.

Hereinafter, the present invention will be described in more detail through examples.

However, the following examples only illustrate the present invention, and the content of the present invention is not limited by the following examples.

[Example]

[Example 1]

To replicate a 3D microstructure with a width of 10㎛, prepare a soft mold with a gap space of 15㎛ initial width and a net-shaped resin cavity, and apply MINS 311RM, an ultraviolet curable resin, to the cavity and gap of the soft mold. The target vertical strain value was set at approximately 0.292, and vertical pressure was applied until the target vertical strain value was reached to deform the shape of the soft mold. MINS 311RM was cured by irradiating broadband ultraviolet rays of 100 mW/cm ² intensity for 1 minute. Afterwards, the vertical pressure was removed and the 3D microstructure was replicated.

[Comparative Example 1]

The 3D microstructure was replicated in the same manner as Example 1, but with a target vertical strain value of about 0.224.

[Comparative Example 2]

The 3D microstructure was replicated in the same manner as Example 1, but with a target vertical strain value of about 0.252.

[Comparative Example 3]

The 3D microstructure was replicated in the same manner as Example 1, but with a target vertical strain value of about 0.324.

[Experimental Example 1] Evaluation of replication form of 3D microstructure

In this experiment, the 3D microstructure of Example 1 was photographed using a scanning electron microscope (SEM), and the replication shape was evaluated.

At this time, for comparison, the 3D microstructures of Comparative Examples 1 to 3 were photographed in the same manner as in Example 1, and the replication shape was evaluated.

First, the target normal strain value ranges from 0.275 to 0.295 to replicate a 10-μm-wide 3D microstructure in a desired shape.

At this time, the range of the target vertical strain value is only the range of the target vertical strain required when replicating a 3D microstructure with a width of 10㎛, but is not limited to this and can be formed in various ways depending on the shape of the 3D microstructure to be replicated. You can.

In Example 1, as shown in (c) of FIG. 9, it can be confirmed that the 3D microstructure is completely connected without being disconnected from each other, and that the shape is formed accurately and firmly.

In addition, in Comparative Example 1, as shown in Figure 9 (a), it can be confirmed that the 3D microstructure is closer to the shape of the spaced space than to the shape of the resin cavity forming a net, and that the shape is not completely formed. there is.

In addition, in Comparative Example 2, as shown in Figure 9 (b), it can be seen that the 3D microstructure has a disconnected network shape, is partially close to the shape of the space, and is not fully formed. there is.

In addition, in Comparative Example 3, as shown in Figure 9 (d), it can be confirmed that the 3D microstructure partially forms a net shape, but there are many disconnected parts, and the shape is not completely formed. .

Through this, the 3D microstructure of Example 1, which is replicated with a target vertical strain within the preferred target vertical strain range, and the 3D microstructure of Comparative Examples 1 to 3, which are replicated with a target vertical strain outside the preferred target vertical strain range. Compared to , it can be judged that the form is copied completely.

Furthermore, it can be confirmed that the 3D microstructure that the user wants to replicate can be replicated with high accuracy using the Poisson effect.

The embodiments of the present invention described above are not implemented only through methods, but may also be implemented through methods for realizing functions corresponding to the configurations of the embodiments of the present invention, configurations included in the methods, etc., and such implementations. can be easily implemented by an expert in the technical field to which the present invention belongs based on the description of the above-described embodiments.

In addition, although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements can also be made by those skilled in the art using the basic concept of the present invention defined in the following claims. It falls within the scope of invention rights.

10: master mold
11: Bulkhead
12: protruding protrusion
20: soft mold
21: Separation space
22: Resin cavity
PE: Poisson effect
R: Resin
VP: vertical pressure

Claims (5)

A soft mold preparation step of forming a soft mold by transferring a superelastic material to the master mold using a soft lithography method;
A resin application step of applying resin to the soft mold;
A compression step of applying vertical pressure to the upper surface of the soft mold and deforming the shape of the soft mold using the Poisson effect caused by the vertical pressure;
A resin curing step of curing the resin by applying heat or ultraviolet rays to the soft mold whose shape has been deformed to create a 3D microstructure; and
A 3D microstructure replication method using the Poisson effect, comprising a release step of removing vertical pressure on the soft mold, restoring the shape of the soft mold, and releasing the 3D microstructure.
According to clause 1,
The soft mold preparation step is,
A 3D microstructure replication method using the Poisson effect, comprising a partition formed in a shape that becomes narrower as the master mold moves upward, and a protruding protrusion formed on an outer surface of the partition.
According to clause 2,
The soft mold preparation step is,
A 3D microstructure replication method using the Poisson effect, wherein the soft mold includes a space formed by the partition wall and a resin cavity that is a space formed by the protruding protrusion.
According to clause 3,
The compression step is,
A 3D microstructure replication method using the Poisson effect, characterized in that the separation space is narrowed by the Poisson effect and the shape of the soft mold is modified so that the resin cavities located adjacent to the separation space are in a connected state.
According to clause 4,
The compression step is,
Poisson, characterized in that the vertical strain according to the change in the current width of the separation space is calculated through the following [Equation 1], and a target vertical strain value is selected from these to deform the shape of the soft mold up to the target vertical strain. 3D microstructure replication method using effects.
[Equation 1]

(here, is the current width of the separation space, is the initial width of the separation space, is the width between the space facing the space, is the vertical strain, is Poisson's ratio.)