KR20120133771A - Stretchable micro-arch structure of conductive organic polymer, stretchable organic electronic device, and method for making thereof - Google Patents

Abstract

PURPOSE: A stretchable micro-arch structure of an organic conducting polymer, stretchable organic electronic device, and a manufacturing method thereof are provided to control individual electrical characteristics of a polymer structure through a micropipette. CONSTITUTION: Provided is a micropipette in which an organic conducting polymer solution is filled. The micropipette comes in contact with a first contact point. A column of the organic conducting polymer solution is formed between the micropipette and the first contact point by isolating the micropipette from the first contact point. The micropipette comes in contact with a second contact point after the column of the solution is solidified. [Reference numerals] (i,iv) Contact; (ii) Separation; (iii) Movement

Description

STRETCHABLE MICRO-ARCH STRUCTURE OF CONDUCTIVE ORGANIC POLYMER, STRETCHABLE ORGANIC ELECTRONIC DEVICE, AND METHOD FOR MAKING THEREOF

The present invention relates to a highly stretchable organic electronic device. More particularly, the present invention relates to the local growth of functional organic materials using micropipettes, to three-dimensional organic structures (particularly micro arches) produced therefrom, and to the highly stretchable organic electronic devices integrated thereby.

Stretchable electronic devices are recognized as a promising future industry. It can be utilized in a variety of applications such as wearable communication devices, displays, life sciences and the like. There are two representative techniques for implementing a stretchable electronic device as follows.

The first is to use a spring thin metal film. Such techniques are disclosed, for example, in BY Ahn et al., “Omnidirectional Printing of Flexible, Stretchable, and Spanning Silver Microelectrodes”, Science 323 , 1590 (2009), which is incorporated herein by reference. When the device is stretched, the spring-like shape absorbs the strain that the device must receive. The document proposes a technique for implementing various electronic devices to operate normally even when stretching 100% or more by using such a metal structure as an electrical wiring.

The second is to use a composite of carbon nanotubes (CNT) and rubber (elastomer). Such techniques are disclosed, for example, in KY Chun et al., “Highly conductive, printable and stretchable composite films of carbon nanotubes and silver”, Nature Nanotechnology 5 , 853 (2010), which is incorporated herein by reference. Carbon nanotubes in the composite provide electrical conductivity and rubber provides high elasticity. Through this, the light emitting device may be normally operated in a stretching condition of 100% or more. However, the technique tends to reduce electrical conductivity as the contact between the carbon nanotube bundles weakens during stretching. This is directly related to the reduction of the performance of the electrical wiring.

The two techniques mentioned above are limited to the implementation of passive interconnections that allow electricity between both devices. In order to integrate and implement many new stretchable devices, it is necessary to implement various stretchable functional active components.

Organics, in particular organic conductive polymers (π-conjugated polymers) have the advantage of freely controlling electrical and optical properties through chemical doping. Because of these superior properties, organic conductive polymers have unlimited application value in the implementation of logic devices and light emitting diodes in the field of microelectronics such as transistors and photo-switches. Have

Patterning techniques have evolved to effectively approach such applications. Typical technologies include soft lithography, inkjet printing, and electro-spinning. The organic polymer structure produced in this manner is in the form of a two-dimensional film. However, this form is not suitable for stretchable device implementation. Despite the excellent flexibility of organic matter, it has been reported to break at stretches of more than 5%. U. Lang et al., “Mechanical Properties of the Intrinsically Conductive Polymer Poly (3,4-Ethylenedioxythiophene) Poly (Styrenesulfonate) (PEDOT / PSS)” , Key Engineering Materials 345-346 , 1189 (2007).

In order to fabricate an electronic device capable of stretching more than 100% using an organic polymer, it would be very effective to implement a three-dimensional structure, particularly an arch structure. This is because the structural characteristics of the arch are expected to effectively absorb the strain received by the device. Therefore, there is a need for a technology that can produce organic polymers in three-dimensional form and align them individually.

An object of the present invention is to form a stretchable microstructure with an organic conductive polymer.

It is another object of the present invention to provide a method for forming a three-dimensional structure of an organic conductive polymer in a desired position and direction at a local position of an electronic device through a micropipette.

It is still another object of the present invention to provide a method of integrating a micro arch of an organic conductive polymer into a stretchable electronic device to implement an extremely stretchable electronic device.

According to the present invention, there is provided a method of manufacturing a stretchable organic conductive polymer 3D structure, preferably a micro arch structure, comprising providing a micro pipette filled with an organic conductive polymer solution, and contacting the micro pipette to a first contact point. Forming a column of the organic conductive polymer solution between the micropipette and the first contact point by separating the micropipette from the first contact point at a predetermined speed, and preferably, after the pillar of the solution is solidified, Contacting the picket with the second contact.

By this method, according to the invention, a three-dimensional microstructure, in particular a micro arch structure, of stretchable organic conductive polymers formed between two spaced apart contacts is formed. The term "arch" is intended here to denote a long, curved shape with a high center, such as a bow or a rainbow.

The organic conductive polymer used to form the micro arch structure may include all kinds of organic conductive polymers. Examples include, but are not limited to, poly (3,4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT: PSS).

In the present invention, the organic conductive polymer is filled into the micropipette in a form dissolved in a solvent. As the solvent of the conductive polymer, all kinds of solvents, including water, can be used.

Dopants may be added to the organic conductive polymer solution to control electrical conductivity. Preferably the dopant includes but is not limited to dimethyl sulfoxide (DMSO) and / or glycol.

The diameter of the micro arch structure can be adjusted by varying the speed of separating the micro pipette from the first contact. That is, as the separation speed increases, the diameter of the micro arch structure decreases. The separation speed can be determined in the range of microns to nanometers / second. For example, the separation speed is preferably in the range of about 1 μm / s to about 120 μm / s, but is not limited thereto.

The micro arch structure is preferably distributed between about 10 μm and about 1 μm in diameter depending on the separation speed of the micro pipette, for example when the lower diameter of the micro pipette is about 10 μm. The arch structure can reach several hundred microns in length.

In forming the micro arch structure, the micro pipette is preferably controlled in microns by a stepping motor.

The arch structure formed according to the invention maintains substantially constant electrical properties of the arch structure until the arch structure is destroyed as the spacing between the two contacts increases.

The present invention provides a method of forming a stretchable electrode wiring in implementing a stretchable electronic device. The method includes using a micropipette filled with an organic conductive polymer solution to connect the electrodes of two or more devices to the organic conductive polymer arch structure. The spacing between the devices can range from micrometers to millimeters.

DMSO is added to the conductive polymer solution for high electrical conductivity. Preferably, the DMSO is added at a concentration of at least 2% by weight to give the polymer arch structure an electrical conductivity of at least 200 S / m.

The method for manufacturing a stretchable electrochemical transistor according to the present invention includes applying an electrolyte to a gate to control the flow of electricity inside the conductive polymer in contact with the gate through a voltage applied to the gate, and filling the organic conductive polymer solution with the gate. Using a micropipette, connecting between the source and the gate of the transistor and between the gate and the drain with a conductive polymer micro arch structure.

Preferably, the gate is formed by sequentially coating PEDOT: PSS and an electrolyte on a metal substrate. The electrolyte preferably consists of 33% by weight of poly (styrenesulfonate), 12% by weight of ethylene glycol, 8% by weight of sorbitol and 0.1M aqueous solution of NaClO ₄ . The conductive polymer solution is preferably a mixture of 5% by weight of ethylene glycol in PEDOT: PSS aqueous solution.

The voltage applied to the gate of the transistor is preferably about 0-1.8V, and the voltage applied between the source and the drain is preferably about 0-1.2V.

Method for implementing a stretchable optical switch device according to the present invention, using a micro pipette filled with an organic conductive polymer solution, connecting the two electrodes between the conductive polymer arch structure, and the light to the arch structure Irradiating periodically to drive the optical switch by varying the amount of current between the two electrodes through the arch structure.

Preferably, the light irradiated onto the arch structure has a higher energy than the bandgap energy of the conductive polymer.

The above-described device or electrode may be embedded in polydimethylsiloxane (PDMS) to enable stretching.

As an aspect of the present invention, a method of making a stretchable three-dimensional organic conductive polymer arch structure with a micro pipette comprises the following steps:

Filling the conductive pipette solution into the micropipette;

Contacting the bottom of the micropipette to one foot structure alignment position of the conductive polymer arch structure in the surface of the substrate;

Separating the pipette from the substrate surface to form a meniscus of the solution between the substrate surface and the bottom of the pipette;

Evaporating the solvent in the formed meniscus in air to solidify the conductive polymer;

Forming a conductive polymer structure of a desired length through solidification of the conductive polymer due to continuous separation and evaporation; And

Contacting the pipette bottom with the other foot structure alignment position of the conductive polymer arch structure in the substrate surface.

The term “meniscus” here refers to a conductive polymer solution column between the bottom of the micropipette and the substrate surface, wherein the diameter of the solution column is substantially smaller than the diameter of the pipette bottom or the portion of the solution in contact with the substrate. It is an expression intended to indicate.

Through the two contacting steps, the spacing between the two foot structures of the conductive polymer arch structure can be controlled by the horizontal motion of the micropipette.

By this method a structure is formed having a stretchability of (length of the structure—the spacing between the two feet) / the spacing between the two feet × 100%. According to the present invention, micro arch structures having a high stretchability can be formed, preferably at least about 20%, more preferably at least about 50%, most preferably at least about 100%, such as at least about 200.

According to one aspect of the invention, fabrication of a three-dimensional microstructure includes the step of solidifying while discharging the polymer solution filled in the micropipette.

According to the present invention, not only can the organic conductive polymer structure having the desired diameter and length be formed through the micropipette, but also the polymer structure can be precisely aligned at a desired position, and the individual electrical characteristics of the polymer structure can be adjusted.

In addition, according to the present invention, a structure that maintains constant electrical characteristics even under extreme stretching conditions may be obtained by controlling the length of the organic conductive polymer arch structure and the spacing between the two foot structures of the arch structure.

In addition, a stretchable electronic device such as an electrical wiring, an electrochemical transistor, an optical switch, and the like may be implemented through the manufactured three-dimensional conductive polymer arch structure.

1A is a conceptual diagram of fabricating a conductive polymer 3D structure through a micropipette according to the present invention.
Figure 1b is a graph showing the correlation with the diameter of the structure obtained according to the separation speed of the 10μm diameter micro pipette containing PEDOT: PSS aqueous solution.
Figure 2a is an optical photograph directly showing the manufacturing process of the conductive polymer three-dimensional arch structure through a micro pipette according to the present invention.
2b and 2c are FE-SEM photographs of the micro arch structure produced by the above process.
3 is a graph showing the relationship between doping concentration and electrical conductivity when DMSO is doped into two kinds of PEDOT: PSS.
Figure 4a is a conceptual diagram of the stretching of the conductive polymer micro arch structure manufactured.
Figure 4b is a graph showing the electrical conductivity change of the arch structure with stretching.
4C is a graph showing the correlation between l _a / L ₀ ratio and stretchability.
5A is a schematic diagram of a stretchable light emitting device in which electrodes between two light emitting devices are connected to a PEDOT: PSS arch structure.
Figure 5b is an optical picture showing the driving according to the stretching of the light emitting device.
5C is a graph illustrating a change in current according to an applied voltage of a light emitting device.
FIG. 6A is a schematic diagram illustrating a stretchable electrochemical transistor using a PEDOT: PSS micro arch structure. FIG.
FIG. 6B is a graph showing a correlation of current flowing between source and drain according to a gate applied voltage of an electrochemical transistor implemented as in FIG. 6A.
FIG. 6C is a graph illustrating the current relationship between source and drain versus time, showing ON / OFF performance of an electrochemical transistor according to stretching conditions.
7A is a schematic diagram of a stretchable optical switch element.
FIG. 7B is a graph showing the relation of photocurrent with time, showing the driving of the optical switch according to the stretching condition in the optical switch element according to FIG. 7A.

Additional aspects, advantages, features and implementations of the invention will be included in the description of the following examples which will be understood in conjunction with the accompanying drawings. The following examples are intended to illustrate preferred embodiments of the present invention in order to enable those skilled in the art to understand and to facilitate the present invention, and should not be construed as limiting the present invention. Those skilled in the art will recognize that various changes and modifications can be made within the spirit and scope of the invention.

1A illustrates the basic concept of forming a conductive polymer microstructure using a micropipette. In the present invention, a key idea for manufacturing a conductive polymer microstructure of a desired shape in a desired position is to locally supply a polymer solution using a micro pipette. When the micropipette containing the polymer solution is brought into contact with the substrate, a meniscus of the solution is formed at the bottom of the pipette. The pipette is then spaced apart from the substrate to evaporate the solvent in the meniscus, thereby forming a solidified microstructure. The reaction continues by successive spacing of the pipettes to form three-dimensional, high aspect ratio conductive polymer microstructures.

One of the great advantages of manufacturing the structure according to the present invention is that the diameter of the structure can be adjusted by changing the separation speed of the pipette. Diameter control is an important factor in controlling the electrical performance of the structure, which can be achieved simply by adjusting the separation speed. Figure 1b is a graph showing the relationship between the diameter of the structure and the separation speed. At this time, the diameter of the lower end of the pipette used in the experiment is 10 μm. As the separation speed increases from 2.6 μm / s to 113.6 μm / s, the diameter of the fabricated structure can be seen to decrease from 9.2 μm to 2.6 μm. This result shows very high reproducibility.

Conductive polymer structures for high stretch are arched. 2A is an optical photograph illustrating a process of manufacturing a micro arch structure. The process consists of four steps: (i) 'contacting' the substrate with the micropipette to form the one-foot structure of the arch; (ii) a 'separation' step of fabricating the desired length of structure; (iii) a 'movement' step of determining the spacing between the two foot structures; And (iv) a second 'contacting' step of the micropicket and substrate to form the remaining foot structure.

2b and 2c are FE-SEM photographs of the micro arch structure produced through the above process. 2B shows a micro arch structure having a constant diameter (2.8 μm) and a length (300 μm). Figure 2c shows that the length of the arch structure can be freely adjusted in this process. In accordance with the present invention, micro arch structures having a diameter of 3.0 μm and an arch length adjusted from 150 μm to 450 μm have been successfully manufactured.

3 shows that the electrical properties of the structure are individually controlled through doping. This is a very important factor in implementing various components of the electronic device, which is a great advantage of the present technology. FIG. 3 shows an example thereof, and the electrical conductivity of the structure according to the doping concentration of DMSO when doping DMSO to two kinds of PEDOT: PSS (PEDOT: PSS 2.2-2.6 wt% and PEDOT: PSS 1.3 wt%) A graph representing. As shown in the graph, the electrical conductivity is adjustable in the range of about 10 ⁴ from 10 ⁻² S / cm to 200 S / cm.

Arch structures made with this technology have high stretchability. Here, the stretchability refers to a value of (LL ₀ ) / L ₀ × 100%, which is a change in the distance between two arch structures of the arch structure when the arch structure starts to break. Where L denotes the spacing between the two foot structures when the stretch occurs, and L ₀ denotes the spacing between the two foot structures initially, i.e., when the arch structure is formed (see FIG. 4A). The stretchability is expected to increase as the ratio l _a / L ₀ increases. Where l _a represents the length of the arch. Thus, longer relative arch lengths will have higher stretchability.

The graph of FIG. 4B shows how the electrical properties of arch structures made in accordance with the present invention tend to under stretch conditions. In the examples the electrical conductivity of the conductive polymer microarch was set to 200 S / cm (PEDOT: PSS 2.2-2.6 wt% high conductivity grade, 2.0 wt% DMSO). The ratio of _{a a} / L _0, which represents the length of the arch with respect to the distance between the two foot structures, was adjusted to 1.0-4.2. Note that the electrical properties remain substantially constant until the arch structure is destroyed. This suggests that the stretch can be kept constant without degrading the performance of the electronic device.

4C is _a graph showing stretchability according to the ratio l _a / L ₀ . Experimentally, we could increase the ratio of L _a / L ₀ to achieve more than 270% of stretchability, which is the highest value currently reported. In addition, the experimental results are similar to the estimate (l _a -L ₀ ) / L ₀ × 100%.

5 shows the application of a micro-arch structure fabricated by the present technology to stretchable electrical interconnects connecting light emitting diodes. The conditions of the conductive polymer solution are PEDOT: PSS 2.2-2.6 wt% high conductivity grade, 2.0 wt% DMSO. The device is implemented as shown in FIG. 5A. The upper and lower electrodes of the two light emitting diodes embedded in the PDMS were connected to each of the arch structures, and a light emitting diode was operated by applying a voltage between the two arch structures. Accordingly, it was confirmed that the operation works well even when stretching the two light emitting diodes. 5B is an optical photograph showing two diodes emitting light upon stretching. As can be seen, the light emission intensity is maintained unchanged even when stretching at 265%. More specifically, the relationship between the voltage and the current at the time of driving the light emitting diode is shown in FIG. 5C. The driving voltage is 2.3 V due to the characteristics of the light emitting diode. As shown in the graph, no current change was found even at the stretch condition of 265%. That is, it can be seen that even in extreme stretch conditions, the conductive polymer arch structure manufactured by the present technology maintains constant performance to the electrical wiring.

6 illustrates an implementation into a stretchable electrochemical transistor in accordance with the present invention. The device is essential for the implementation of electrical logic circuits. Figure 6a shows a diagram of the transistor, which is realized by connecting between the electrolyte gate (G) and the source (S) and between the electrolyte gate (G) and the drain (D) with a conductive polymer microarch according to the invention. . In the present embodiment, the conductive polymer solution is a material in which 5 wt% ethylene glycol is mixed with PEDOT: PSS aqueous solution. The electrolyte gate is fabricated with a sequential coating of the conductive polymer solution and the electrolyte. The electrolyte consists of 33 wt% poly (styrenesulfonate), 12 wt% ethylene glycol, 8 wt% sorbitol, and 0.1 M aqueous NaClO ₄ solution.

The driving principle of the electrochemical transistor is as follows. The redox reaction in the PEDOT: PSS portion in contact with the electrolyte of the gate changes the electrical conductivity of PEDOT: PSS to regulate the electrical flow between the source-drain flowing through it. Oxidation and reduction are controlled by the voltage applied to the gate. When the applied voltage is 0V, it is kept 'ON' due to the high electrical conductivity of PEDOT: PSS oxidized by doping, and when the applied voltage is increased in the positive direction, PEDOT: PSS of the part in contact with the electrolyte is reduced and the electrical conductivity is Decreases and this causes the state to be 'OFF'. 6B shows that the ON / OFF ratio of the current has about 10 ⁴ depending on the voltage applied to the gate. As the gate applied voltage increased from 0V to 1.8V, the current was reduced to about 10 ⁴ magnitudes. It can be seen from FIG. 6C that the ON / OFF switching operates normally without changing even in a stretching condition of 120% or more.

7 illustrates a stretchable optical switch implementation. To implement this, the two electrodes embedded in PDMS were connected with a conductive polymer PEDOT: PSS micro arch structure according to the method of the present invention, and light was irradiated there. The irradiated light is a laser of 650 nm wavelength, as shown in FIG. 7A, having an energy higher than the band gap energy of PEDOT: PSS.

7B shows the optical switch behavior. This is the current change when the laser pulse is applied at 60 / min frequency and 5V voltage is applied to both electrodes. When the laser is irradiated, the current rises rapidly. When the laser irradiation was stopped, the original current value was restored. This optical switch drive was driven without significant change even under 105% stretch conditions.

Although the present invention has been described with reference to particular exemplary embodiments, it is to be understood that the invention is not limited by the examples, but is limited only by the claims. It should be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.

Claims (29)

A three-dimensional microstructure of stretchable organic conductive polymer formed between two spaced apart contacts. 3. The three-dimensional microstructure of claim 1, wherein the three-dimensional microstructure is a micro arch structure and the stretchability of the arch structure is 20% or more. 3. The three-dimensional microstructure of claim 1, wherein the electrical characteristics of the arch structure remain substantially constant until the arch structure is destroyed as the spacing between the two contacts increases. . The three-dimensional microstructure of claim 1, wherein the arch structure has a diameter in the range of 10 μm to 1 μm. The three-dimensional microstructure according to claim 1 or 2, wherein the organic conductive polymer is poly (3,4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT: PSS). The three-dimensional microstructure of claim 1, wherein the organic conductive polymer is doped with a dopant. The three-dimensional microstructure of claim 6, wherein the dopant is dimethyl sulfoxide (DMSO) or glycol. 7. The three-dimensional microstructure of claim 6, wherein the electrical conductivity of the micro arch structure is in a range between 10 ^-2 S / cm and 200 S / cm. A method of manufacturing a three-dimensional microstructure of a stretchable organic conductive polymer,
Providing a micro pipette filled with an organic conductive polymer solution;
Contacting the micro pipette with a first contact;
Separating the micropipette from the first contact point at a predetermined speed to form a pillar of the organic conductive polymer solution between the micropipette and the first contact point; And
Contacting the micro picket with a second contact;
3D microstructure manufacturing method comprising a. The method of claim 9, wherein the three-dimensional microstructure is a micro-arch structure, and the contacting with the second contact is performed after the pillar of the solution is solidified. 11. The method of claim 9 or 10, wherein said spacing step is performed to control the diameter of said microstructure by adjusting the rate at which said micropipette is spaced from said first contact. The three-dimensional microstructure of claim 11, wherein the separation speed is in a range between 1 μm / s and 120 μm / s and the diameter of the micro arch structure is in a range between 10 μm and 1 μm. Manufacturing method. The method of claim 9 or 10, wherein the conductive polymer solution is a three-dimensional microstructure manufacturing method characterized in that the PEDOT / PSS is dissolved in a solvent. The method of claim 9, wherein the organic conductive polymer solution is added with DMSO or glycol as a dopant. The method of claim 9 or 10, wherein the micropipette is controlled in microns by a stepping motor. A method of forming stretchable electrode wiring in a stretchable electronic device,
Providing an organic conductive polymer solution;
Filling a micropipette with the conductive polymer solution; And
Connecting the electrodes of two or more devices to the organic conductive polymer arch structure by using the micropipette filled with the conductive polymer solution;
Stretchable electrode wiring forming method comprising a. The method of claim 16, wherein providing the conductive polymer solution comprises adding DMSO. 18. The method of claim 17 wherein the DMSO is added at a concentration of at least 2% by weight to provide an electrical conductivity of at least 200 S / m. As a method of manufacturing a stretchable electrochemical transistor,
Applying an electrolyte to the gate of the transistor to regulate the internal electrical flow of the conductive polymer micro arch structure via the gate voltage; And
Using a micropipette filled with an organic conductive polymer solution, connecting between the source and the gate of the transistor and between the gate and the drain with a conductive polymer microarch structure;
Stretchable electrochemical transistor manufacturing method comprising a. 20. The method of claim 19, wherein the gate is formed by sequentially coating PEDOT: PSS and an electrolyte on a metal substrate. 21. The stretchable electric machine according to claim 20, wherein the electrolyte consists of 33 wt% poly (styrenesulfonate), 12 wt% ethylene glycol, 8 wt% sorbitol and 0.1 M aqueous solution of NaClO ₄ . How to make a chemical transistor. 22. The method of claim 19, wherein the conductive polymer solution is mixed with 5 wt% ethylene glycol in a PEDOT: PSS aqueous solution. 22. The method according to any one of claims 19 to 21, wherein the voltage applied to the gate is in the range of 0V to 1.8V and the voltage applied between the source and the drain is in the range of 0V to 1.8V. A method for producing a stretchable electrochemical transistor. As a method of implementing a stretchable optical switch device,
Using a micropipette filled with an organic conductive polymer solution, connecting the two electrodes with a conductive polymer arch structure; And
Periodically irradiating light onto the arch structure to change an amount of current between two electrodes through the arch structure;
Stretchable optical switch device implementation method comprising a. 25. The method of claim 24, wherein the energy of the irradiated light is higher than the bandgap energy of the conductive polymer. 26. The method of claim 24 or 25, wherein the electrode is embedded in polydimethylsiloxane (PDMS). A method of manufacturing a stretchable three-dimensional organic conductive polymer arch structure by using a micro pipette,
Filling the conductive pipette solution into the micropipette;
Contacting the bottom of the micropipette to one foot structure alignment position of the conductive polymer arch structure in the surface of the substrate;
Separating the pipette from the substrate surface to form a meniscus of the solution between the substrate surface and the bottom of the pipette;
Evaporating the solvent in the formed meniscus in air to solidify the conductive polymer;
Forming a conductive polymer structure of a desired length through solidification of the conductive polymer due to continuous separation and evaporation; And
Contacting the pipette bottom with the other foot structure alignment position of the conductive polymer arch structure in the substrate surface;
Micro arch structure manufacturing method comprising a. 28. The method of claim 27, wherein the distance between the two foot structures of the conductive polymer arch structure is adjusted by moving the micro pipette in the horizontal direction through the two contacting steps. Solidifying the discharge while discharging the polymer solution filled in the micro pipette 3D microstructure manufacturing method.

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