DNA ANALYSIS DEVICE

According to an aspect of the present disclosure, a DNA analysis device includes a substrate; a photosensitive organic layer configured to be disposed on the substrate, and expanded or contracted by reacting to light; a pair of sensing electrodes disposed on the photosensitive organic layer, and spaced apart from each other with a nano gap; and a light irradiation unit configured to irradiate the light to the photosensitive organic layer, and when the photosensitive organic layer is deformed, the nano gap between the pair of sensing electrodes is varied. Accordingly, the nano gap is simply and precisely adjusted by using the photosensitive organic layer which reacts to light to enhance DNA analysis accuracy.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of Korean Patent Application No. 10-2022-0076588 filed on Jun. 23, 2022, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

BACKGROUND

Technical Field

The present disclosure relates to a deoxyribonucleic acid (DNA) analysis device, and more particularly, to a DNA analysis device capable of controlling a nano gap.

Description of the Related Art

In recent years, a technology of analyzing a DNA sequence has been used in health fields such as personalized medical services and disease treatment. Gene information can be decrypted through DNA base sequence analysis, and based on this, personal medicine development and disease treatment can be performed, and gene-related technologies can be developed.

Initially, the Sanger method was used, which cuts a gene into small units and chemically amplifies the cut genes, and then analyzes the cut gene units through labeling, but the Sanger method is slow and expensive. Thereafter, analysis time was significantly reduced by development of a cyclic-array method that improved the Sanger method through parallelization. However, such a method is still associated with large cost and long time, and has a problem in that rapid DNA diagnosis is difficult.

In recent years, a nano technology has been developed and research on a DNA sequence analysis method using a nano device has been underway, and an interest in an analysis device having a nano gap among them has increased. When DNA passes between electrodes with the nano gap, instantaneous electrical current is measured to quickly analyze a base sequence.

BRIEF SUMMARY

The inventors have identified that it is difficult to control the nano gap accurately.

A benefit achieved by the present disclosure is to provide a DNA analysis device capable of controlling a nano gap between a pair of sensing electrodes.

Another benefit achieved by the present disclosure is to provide a DNA analysis device capable of precisely aligning a tip electrode of each of a pair of sensing electrodes.

Yet another benefit achieved by the present disclosure is to provide a DNA analysis device capable of minimizing or reducing noise and controlling the nano gap.

Still yet another benefit achieved by the present disclosure is to provide a DNA analysis device capable of quickly and precisely analyzing a base sequence of DNA.

Further yet another benefit achieved by the present disclosure is to provide a DNA analysis device capable of easily controlling the nano gap between a pair of sensing electrodes by using a photosensitive organic layer which is expanded by light.

Benefits of the present disclosure are not limited to the above-mentioned benefits, and other benefits, which are not mentioned above, can be clearly understood by those skilled in the art from the following descriptions.

In order to achieve the benefits, according to an aspect of the present disclosure, a DNA analysis device includes a substrate; a photosensitive organic layer configured to be disposed on the substrate, and expanded or contracted by reacting to light; a pair of sensing electrodes disposed on the photosensitive organic layer, and spaced apart from each other with a nano gap; and a light irradiation unit configured to irradiate the light to the photosensitive organic layer, and when the photosensitive organic layer is deformed, the nano gap between the pair of sensing electrodes is varied. Accordingly, the nano gap is simply and precisely adjusted by using the photosensitive organic layer which reacts to light to enhance DNA analysis accuracy.

In accordance with various embodiments, a device includes: a first tip electrode including a first nanowire; a second tip electrode including a second nanowire; a nano gap separating the first tip electrode from the second tip electrode; an insulating layer underlying the first tip electrode and the second tip electrode; a groove in the insulating layer, the groove overlapping the first and second tip electrodes; a photosensitive organic layer underlying the insulating layer; and a controller operable to direct polarized light onto the photosensitive organic layer while a deoxyribonucleic acid (DNA) strand passes through the nano gap.

In accordance with various embodiments, a method includes: forming a photosensitive organic layer on a flexible substrate; forming an insulating layer on the photosensitive organic layer; forming a groove in the insulating layer; forming a nanowire on the insulating layer on either side of the groove and extending across the groove; and forming a pair of tip electrodes separated by a nano gap by passing an electrical current through the nanowire.

Other detailed matters of the example embodiments are included in the detailed description and the drawings.

According to the present disclosure, the nano gap between a pair of sensing electrodes may be precisely controlled.

According to the present disclosure, a deformation direction of the photosensitive organic layer and the nano gap may be easily controlled by adjusting a polarization direction of light irradiated to the photosensitive organic layer.

According to the present disclosure, a location of the tip electrode of each of a pair of sensing electrodes may be precisely aligned.

According to the present disclosure, the noise can be minimized or reduced and the nano gap may be controlled at the time of analyzing DNA.

According to the present disclosure, a DNA base sequence may be quickly and precisely analyzed.

DETAILED DESCRIPTION

Hereinafter, a DNA analysis device according to example embodiments of the present disclosure will be described in detail with reference to accompanying drawings.

FIG.1is a schematic diagram of a DNA analysis device according to an example embodiment of the present disclosure.

The DNA analysis device100is a device that analyzes a base sequence of DNA by using a nano gap. The DNA analysis device100detects a change of current which varies depending on each base when the DNA passes through the nano gap between a pair of sensing electrodes SE to analyze the base sequence of DNA.

Referring toFIG.1, the DNA analysis device100includes a main body110including a pair of sensing electrodes SE spaced apart from each other with the nano gap G, a light irradiation unit or assembly120irradiating light to the main body110to control the nano gap G, and a control unit or control circuit or controller130controlling the main body110and the light irradiation unit120.

The main body110is a diagnosis kit into which DNA to be analyzed is input. The main body110may include a pair of sensing electrodes SE having the nano gap G, and analyze the base sequence of the DNA by a scheme of detecting the current change when the DNA passes through the nano gap G between a pair of sensing electrodes SE. In addition, the main body110may include a photosensitive organic layer112that is deformed in response to the light and adjusts the nano gap G by a scheme of deforming the photosensitive organic layer112. The main body110including the photosensitive organic layer112will be described below in more detail with reference toFIGS.2A to4.

The light irradiation unit120is a component that irradiates the light to the main body110to control the nano gap G. The light irradiation unit120may selectively irradiate the light to the main body110according to the control by the control unit130. The light irradiation unit120includes a light source121, a digital micro mirror122, and a polarizer123.

The light source121is operable to generate light having a wavelength band that may cause a reaction in the photosensitive organic layer112of the main body110. The light from the light source121may be incident on the main body110via the digital micro mirror122and the polarizer123and the photosensitive organic layer112of the main body110may be deformed in response to light. Meanwhile, the photosensitive organic layer112has a different wavelength band of a light which reacts to a material. Therefore, the light source121may be variously designed by considering the material of the photosensitive organic layer112, and for example, the light source121may be a laser that emits light having wavelength of approximately 200 to 400 nm, but is not limited thereto.

The digital micro mirror122includes a plurality of micro mirrors which sends the incident light at a desired angle. Each of the plurality of micro mirrors is configured to adjust the angle to reflect the light from the light source121to a specific point of the main body110. More particularly, the digital micro mirror122reflects the light from the light source121to the photosensitive organic layer112of the main body110. By using the digital micro mirror122, the light is incident on only a part of the photosensitive organic layer112or the light is incident on the entirety of the photosensitive organic layer112by using the digital micro mirror122, which is beneficial to deform the photosensitive organic layer112to various forms.

The polarizer123is a linear polarizer that linearly polarizes the light. The light reflected by the digital micro mirror122may be irradiated to the main body110via the polarizer123. The photosensitive organic layer112of the main body110may be included in a specific wavelength band and deformed in reaction to a light linearly polarized in a specific direction. Therefore, the polarizer123is disposed between the digital micro mirror122and the main body110to provide the linearly polarized light to the main body110and the photosensitive organic layer112may be deformed by reacting to the linearly polarized light. More specifically, the polarizer123is disposed between the digital micro mirror122and the substrate111so that the light reflected by the digital micro mirror122is linearly polarized and incident on the photosensitive organic layer112. Since the photosensitive organic layer112may be expanded in a direction parallel to a polarization direction of the linearly polarized light, a polarization axis of the polarizer123may be designed by considering an expansion direction of the photosensitive organic layer112, and this will be described below in more detail with reference toFIG.3.

Meanwhile, inFIG.1, it is illustrated that the light irradiation unit120includes one polarizer123, but the light irradiation unit120may also include a plurality of polarizers123by considering the number of photosensitive organic layers112and a deformation direction of the photosensitive organic layer112, and the present disclosure is not limited thereto.

The control unit130is a component that controls and drives the light irradiation unit120and the main body110. The control unit130includes a light irradiation control unit or circuit or light irradiation controller131connected to the light irradiation unit120, and an analysis unit or circuit132and a power supply unit or circuit or assembly133connected to the main body110.

The light irradiation control unit131is connected to the light irradiation unit120to control the light irradiation unit120. For example, the light irradiation control unit131is connected to the digital micro mirror122and controls the angle of each of the plurality of micro mirrors to control a direction, an intensity, etc., of the light incident on the main body110.

The analysis unit132analyzes the base sequence of the DNA by detecting the electrical current change of the main body110. The analysis unit132is electrically connected to a pair of sensing electrodes SE of the main body110to detect the change of a current which flows on the pair of sensing electrodes SE when the DNA passes through the nano gap G (or “nanogap G” or “nano-gap G”) between the pair of sensing electrodes SE. The nano gap G between the pair of sensing electrodes SE has a size corresponding to the DNA, and the analysis unit132may detect a current which flows on a pair of sensing electrodes SE and the DNA when the DNA passes between a pair of sensing electrodes SE. Therefore, the analysis unit132may analyze the base sequence of the DNA based on the current varying according to a molecular structure of each base while the DNA passes through the nano gap G. It should be understood that the nano gap G may have at least one dimension that is in a nanoscale range. For example, the nanoscale range may be less than 1000 nanometers (nm), less than 100 nm or less than 10 nm.

The power supply unit133applies a voltage to the pair of sensing electrodes SE. The power supply unit133applies the voltage to the pair of sensing electrodes SE to drive the main body110. In some embodiments, the power supply unit133may also be designed as a separate component from the control unit130, and the present disclosure is not limited thereto.

Hereinafter, the main body110of the DNA analysis device100according to an example embodiment of the present disclosure will be described in more detail with reference toFIGS.2A to4.

FIG.2Ais a plan view of a main body of the DNA analysis device according to an example embodiment of the present disclosure.FIGS.2B and2Care cross-sectional views of the main body of the DNA analysis device according to an example embodiment of the present disclosure.FIG.3is a diagram for describing a photosensitive organic layer of the DNA analysis device according to an example embodiment of the present disclosure.FIG.4is a graph for describing a bending angle depending on a light irradiation time of the photosensitive organic layer of the DNA analysis device according to an example embodiment of the present disclosure.

Referring to bothFIGS.2A and2B, the main body110includes a substrate111, the photosensitive organic layer112, an insulating layer113, a metallic pattern114, and a pair of sensing electrodes SE.

The substrate111is a substrate111for supporting and protecting other components of the main body110. The substrate111as a transparent flexible substrate111may be made of an insulating material which may be bent or extended. The substrate111may be made of a transparent material so that the light from the light irradiation unit120may be incident on the photosensitive organic layer112, and made of a material having flexibility to be deformed with the deformation of the photosensitive organic layer112. For example, the substrate111may be made of silicone rubber such as polydimethylsiloxane (PDMS), elastomer such as polyurethane (PU), polytetrafluoroethylene (PTFE), etc., but the present disclosure is not limited thereto.

The photosensitive organic layer112may be deformed by reacting to the light irradiated from the light irradiation unit120. The photosensitive organic layer112may be expanded or contracted according to a wavelength of the irradiated light. For example, when the light irradiation unit120irradiates a light of a UV region to the photosensitive organic layer112, the photosensitive organic layer112may be expanded by reacting to the light of the UV region. When the light irradiation unit120does not irradiate the light and the photosensitive organic layer112is thus exposed to a light of a visible-ray area, the photosensitive organic layer112is contracted to return to an original state thereof again. The visible-ray area or spectrum of visible light may correspond to wavelengths in a range of about 380 nm to about 750 nm. The UV region may correspond to wavelengths in a range of about 10 nm to about 400 nm, such as between about 100 nm and 380 nm.

Referring toFIG.3, the photosensitive organic layer112may be configured by mixing a polymer constituting or including an organic matrix with a photosensitive material112m. As described above, the photosensitive material112mis a material which reacts to a specific wavelength, and for example, crosslinked liquid-crystalline polymers (CLCPs) including azobenzene series, block copolymer particles (BCPs) including nitrobenzyl esters series and coumarin esters series, or the like may be used, and CLCPs and BCPs series materials may also be mixed and used for reactivity adjustment and improvement of the photosensitive organic layer112according to the wavelength of the light.

Referring to bothFIGS.2C and3, the photosensitive organic layer112may be expanded and contracted in the polarization direction of the linearly polarized light. The photosensitive organic layer112may be expanded in a direction parallel to the polarization direction of the light. The photosensitive organic layer112may include the photosensitive material112mwhich reacts to the light linearly polarized in a specific or selected direction, and may be expanded and contracted in the specific or selected direction. For example, when a light which is linearly polarized at 0 degrees is irradiated to the photosensitive organic layer112, the photosensitive organic layer112may be expanded in an X-axis direction by some photosensitive materials112mwhich react to the 0-degree linearly polarized light as in a top left end ofFIG.3. Similarly, when a light which is linearly polarized at 90 degrees is irradiated to the photosensitive organic layer112, the photosensitive organic layer112may be expanded in a Y-axis direction by some photosensitive materials112mwhich react to the 90-degree linearly polarized light as in a top right end ofFIG.3. Further, when a light which is linearly polarized at 135 degrees is irradiated to the photosensitive organic layer112, the photosensitive organic layer112may be expanded in a diagonal direction by some photosensitive materials112mwhich react to the 135-degree linearly polarized light as in a bottom left end ofFIG.3, and when a light which is linearly polarized at 45 degrees is irradiated to the photosensitive organic layer112, the photosensitive organic layer112may be expanded in the diagonal direction by some photosensitive materials112mwhich react to the 45-degree linearly polarized light as in a bottom right end ofFIG.3.

Therefore, when the photosensitive organic layer112is constituted by or includes a plurality of photosensitive materials112mwhich is randomly aligned or aligned according to a selected pattern, the light linearly polarized in the specific direction is irradiated to the photosensitive organic layer112to deform the photosensitive organic layer112only in the specific or selected direction. Further, the photosensitive materials112mof the photosensitive organic layer112are aligned only in the specific or selected direction through rubbing or light alignment to fix an expansion direction of the photosensitive organic layer112to the specific or selected direction. For example, the plurality of photosensitive materials112mconstituting the photosensitive organic layer112may be aligned in the direction parallel to the polarization direction.

A solid content ratio of the photosensitive material112mconstituting or included in the photosensitive organic layer112may be designed by considering a reaction speed of the photosensitive organic layer112. When the content ratio of the photosensitive material112mis smaller, the reaction speed of the photosensitive organic layer112may decrease, and on the contrary, when the content ratio is the higher, the reaction speed of the photosensitive organic layer112may increase. For example, the solid content ratio of the photosensitive material112mmay be approximately 20% to 35%. Therefore, an approximate amount of photosensitive material112mmay be mixed with the organic matrix polymer in a manner beneficial to select the reaction speed of the photosensitive organic layer112.

Meanwhile, the reactivity of the photosensitive organic layer112may vary depending on the thickness of the photosensitive organic layer112. For example, as the thickness of the photosensitive organic layer112increases, the reactivity of the photosensitive organic layer112increases, so the photosensitive organic layer112may be more deformed. However, when the thickness of the photosensitive organic layer112exceeds a predetermined or selected numerical value, e.g., approximately 18 μm, the reactivity reaches a saturation state, so a deformation level of the photosensitive organic layer112has a limitation. Therefore, by considering this, the thickness of the photosensitive organic layer112may be selected. For example, selecting a thickness of less than about 18 μm for the photosensitive organic layer112may be beneficial to reduce overall thickness of the main body110.

In addition, referring toFIG.4jointly, the reactivity of the photosensitive organic layer112may vary depending on a material type and a light irradiation time. When a light having the same intensity is irradiated to the photosensitive organic layer112for the same time, the reactivity may vary depending on the type of photosensitive material112m. For example, a photosensitive organic layer112made of PAzo/PDMS has a largest reactivity, so the photosensitive organic layer112may be bent at up to approximately 90 degrees, and a photosensitive organic layer112made of only PAzo has a low reactivity, so the photosensitive organic layer112may be bent at up to approximately 60 degrees.

Further, as a time for which the light is irradiated to the photosensitive organic layer112increases, the reactivity of the photosensitive organic layer112may increase. For example, in the case of all of three photosensitive organic layers112made of PAzo/PDMS, PAzo/PDDMA, and PAzo, respectively, it may be confirmed that with increased time of irradiating the light, the bending angle gradually increases.

Therefore, the reactivity and the reaction speed of the photosensitive organic layer112may be determined or selected based on the type of the photosensitive material112mconstituting or included in the photosensitive organic layer112, the content ratio of the photosensitive material112m, the thickness of the photosensitive organic layer112, the intensity of the light, and the irradiation time of the light.

Referring back toFIGS.2A and2B, the insulating layer113is disposed on the photosensitive organic layer112. The insulating layer113may protect the photosensitive organic layer112so as to prevent the photosensitive organic layer112from being exposed to the outside. The insulating layer113may be disposed to cover the photosensitive organic layer112made of an organic material, and may protect the photosensitive organic layer112from being deformed by external moisture or oxygen. In this case, a depth of a groove113aof the insulating layer113may be determined within a range in which the photosensitive organic layer112is not exposed from the insulating layer113. Further, the insulating layer113may insulate the photosensitive organic layer112from other components of the main body110. The insulating layer113may be made of the material having the flexibility so as to be bent with the deformation of the photosensitive organic layer112. For example, the insulating layer113and the substrate111may be made of or include the same material, and made of silicone rubber such as polydimethylsiloxane (PDMS), elastomer such as polyurethane (PU), polytetrafluoroethylene (PTFE), etc., but the present disclosure is not limited thereto.

The insulating layer113includes a groove113adisposed to overlap with the nano gap G between a pair of sensing electrodes SE. The groove113amay be disposed to correspond to the nano gap G between a pair of sensing electrodes SE. When the photosensitive organic layer112is expanded, a stress may be concentrated more on the insulating layer113which is discontinuously formed than on the substrate114which is continuously formed, and the insulating layer113may be more easily stretched than the substrate111. Therefore, when the photosensitive organic layer112is expanded, the main body110may be bent so that the insulating layer113with the groove113ais extended and the substrate111is contracted. That is, as illustrated inFIG.2C, as the photosensitive organic layer112is expanded, the substrate111, the photosensitive organic layer112, and the insulating layer113may be bent to be convex upward around the groove113a, and the nano gap G may also be changed. Therefore, the groove113afor concentrating the stress on the insulating layer113may be formed in a manner beneficial so that the substrate111, the photosensitive organic layer112, and the insulating layer113are deformed in a specific or selected direction, i.e., in a direction to be convex upward. For example, the groove113amay have the cross-sectional profile depicted inFIGS.2B and2C, in which sidewalls of the groove113aare tapered linearly toward the substrate111. In some embodiments, the groove113amay have different shape than that depicted inFIGS.2B and2C. For example, the groove113amay have one or more curved sidewalls. The groove113amay terminate in a point in the cross-sectional profile.

The metallic pattern114is disposed on the insulating layer113. A pair of metallic patterns114may be disposed on the insulating layer113with the groove113aof the insulating layer113interposed therebetween. In some embodiments, each of the pair of metallic patterns114has a sidewall that terminates at the groove113a. The metallic pattern114as an electrode used in a forming process of a tip electrode115configured by a nanowire (or “nano wire”) of a pair of sensing electrodes SE will be described below with reference toFIG.5B.

A pair of sensing electrodes SE spaced apart from each other with the nano gap G are disposed on the metallic pattern114. A part of the sensing electrode SE may be disposed on the metallic pattern114, and the remaining part may overlap with the groove113a. Therefore, the nano gap G of a pair of sensing electrodes SE may be disposed to correspond to the groove113a. Each of a pair of sensing electrodes SE includes the tip electrode115disposed on the metallic pattern114and a connection electrode116disposed on the tip electrode115.

The tip electrode115is an electrode configured by the nano wire and forming the nano gap G. A pair of tip electrodes115may be disposed spaced apart from each other with the nano gap G. Each of a pair of tip electrodes115may be disposed so that a part overlaps with the groove113aof the insulating layer113, and the remaining part overlaps with the metallic pattern114.

The connection electrode116is disposed on the tip electrode115. A pair of connection electrodes116may be disposed to correspond to a pair of tip electrodes115. Each of a pair of connection electrodes116may be disposed to be spaced apart from the groove113aof the insulating layer113, and to cover the tip electrode115. A pair of connection electrodes116may electrically connect the control unit130and the tip electrode115. Therefore, the voltage may be applied to a pair of connection electrodes116from the control unit130, and the control unit130may detect the current which flows on the tip electrode115when the DNA passes through the nano gap G through the connection electrode116.

Meanwhile, the nano gap G may have an interval corresponding to the DNA so that the DNA passes through the nano gap G. When the nano gap G is excessively small, the DNA base sequence may not be analyzed, and when the nano gap G is excessively large, DNA strands may pass through the nano gap G in a clumping state, so accurate base sequence analysis may be difficult. Therefore, in the DNA analysis device100according to an example embodiment of the present disclosure, the linearly polarized light is irradiated to the photosensitive organic layer112of the main body110to simply adjust the nano gap G.

Referring toFIGS.2A and2C, the DNA analysis device100deforms the photosensitive organic layer112to adjust the nano gap G. When the photosensitive organic layer112is deformed, the nano gap G between the pair of sensing electrodes SE is varied. First, the light irradiation unit120irradiates the linearly polarized light to the photosensitive organic layer112of the main body110to deform the main body110. For example, the light is irradiated to the photosensitive organic layer112to bend the main body110to be convex upward.

The photosensitive organic layer112is controlled to be expanded in a longitudinal direction of a pair of sensing electrodes SE, i.e., the X-axis direction to bend the main body110to be convex upward. In this case, the light linearly polarized in the X-axis direction is irradiated to the main body110to expand the photosensitive organic layer112in the X-axis direction. The photosensitive organic layer112may be expanded in the longitudinal direction of a pair of sensing electrodes SE by reacting to the linearly polarized light, and the substrate111, the photosensitive organic layer112, and the insulating layer113may be bent to be convex toward of the top of the substrate111around the groove113aon which the stress is concentrated. Therefore, as the main body110is bent around the groove113a, a nano gap G′ between a pair of sensing electrodes SE may increase. In this case, by adjusting the intensity and the irradiation time of the light, the bending angle and the nano gap G of the main body110may be precisely controlled. The nano gap G may be referred to as a first nano gap G and the nano gap G′ may be referred to as a second nano gap G′. The second nano gap G′ may have at least one dimension (e.g., along the X-axis direction) that exceeds that of the first nano gap G.

Meanwhile, the nano gap G between a pair of sensing electrodes SE has a very small size, and in order to form the nano gap G, semiconductor equipment that is capable of performing a micro process is beneficial. However, when forming a nanoscale nano gap, there is a problem in that it is difficult to implement the nano gap G designed due to a process error, etc.

Therefore, in the DNA analysis device100according to an example embodiment of the present disclosure, the photosensitive organic layer112is formed in the main body110to easily adjust the nano gap G. The photosensitive organic layer112is a layer that has a property of being expanded and contracted by the light, and the photosensitive organic layer112is deformed to bend the main body110. When the photosensitive organic layer112is expanded, and the main body110is thus bent around the groove113a, the size of the nano gap G of the sensing electrode SE positioned on the groove113amay be changed. Therefore, the photosensitive organic layer112is deformed to control the nano gap G between a pair of sensing electrodes SE to a desired or selected size. For example, when the light linearly polarized in the longitudinal direction of the sensing electrode SE is irradiated to the main body110to expand the photosensitive organic layer112in the longitudinal direction of the sensing electrode SE, the insulating layer113and the substrate111surrounding the photosensitive organic layer112may be deformed. The insulating layer113and the substrate111may be bent around the groove113aon which the stress is concentrated by the expansion of the photosensitive organic layer112, and the main body110may be bent and the size of the nano gap G between a pair of sensing electrodes SE may increase. On the contrary, when the light is not irradiated to the main body110or is irradiated more weakly to the main body110, and the photosensitive organic layer112is contracted to the original state or a less deformed state, the insulating layer113and the substrate111may return to a flat state or a less curved state from the bending state, and the size of the nano gap G may decrease. Accordingly, in the DNA analysis device100according to an example embodiment of the present disclosure, the nano gap G between a pair of sensing electrodes SE may be simply adjusted by just irradiating the light without the semiconductor equipment which is expensive.

Hereinafter, a manufacturing method of the DNA analysis device100according to an example embodiment of the present disclosure will be described with reference toFIGS.5A to5D.

FIGS.5A to5Dare process diagrams for describing a manufacturing method of a DNA analysis device according to an example embodiment of the present disclosure.

Referring toFIG.5A, on the substrate111, the photosensitive organic layer112is formed, and the insulating layer113covering the photosensitive organic layer112is formed. Subsequently, a metallic layer for forming the metallic pattern114is formed on the insulating layer113. In addition, the metallic pattern114and the insulating layer113are partially etched to form the groove113a. The groove113amay be formed on the insulating layer113to correspond to the nano gap G.

Referring toFIG.5B, a nano wire layer NW constituting or included in the tip electrode115is formed by using an electro-hydro-dynamic (EHD) printing scheme. The tip electrode115constituted by or including nano wires may be formed by an electrical radiation scheme. A solution in which the nano wires are distributed may be applied onto the metallic pattern114by using a cone-jet in a nozzle NZ. In this case, voltages having opposite polarities are applied to the nozzle NZ and the metallic pattern114to smoothly form the nano wire made of a conductive material on the substrate111. However, inFIG.5B, it is described that the nano wire layer NW for forming the tip electrode115is formed by the EHD printing scheme, but the nano wire layer NW and the tip electrode115may be formed by other schemes other than the EHD printing scheme, and the metallic pattern114may be omitted depending on the scheme, and the present disclosure is not limited thereto.

Referring toFIG.5C, a pair of connection electrodes116are formed on the nano wire layer NW. The pair of connection electrodes116may be spaced apart from each other with the groove113ainterposed therebetween. One connection electrode116may cover one end of the nano wire layer NW disposed at one side of the groove113a, and the remaining connection electrode116may cover the other end of the nano wire layer NW disposed at the other side of the groove113a.

Referring toFIG.5D, electrical current flows on the connection electrode116and the nano wire layer NW to separate one nano wire layer NW into a pair of tip electrodes115. Referring toFIG.5B, portions of the nano wire layer NW formed on the metallic pattern114on either side of the groove113aare connected to each other unlike a pair of tip electrodes115which are spaced apart from each other. Therefore, a middle portion of the nano wire is cut to form a pair of tip electrodes115spaced apart from each other to form the nano gap G.

To this end, in the related art, the nano wire layer NW is intended to be patterned by using the semiconductor equipment capable of performing the micro process, but a nano-scale delicate patterning process is not easy, and it is difficult to pattern the nano wire layer NW to form a nano gap G having a specific or selected numerical value due to a process error, etc. Therefore, in the manufacturing method of the DNA analysis device100according to an example embodiment of the present disclosure, when the nano wire layer NW is formed, a radiation speed is adjusted, and high current flows on the nano wire layer NW to disconnect the nano wire layer NW. Specifically, when the nano wire layer NW is formed, the radiation speed is adjusted to form the middle portion of the nano wire layer NW which overlaps with the groove113ato be formed thinner than the remaining portion. In addition, when the high current flows on the nano wire layer NW through the connection electrode116, the thinly formed middle portion may be disconnected.

Therefore, in the manufacturing method of the DNA analysis device100according to an example embodiment of the present disclosure, the current is applied to the nano gap G of the nano wire to simply form the nano gap G. In order to disconnect the middle portion of the nano wire, the semiconductor equipment capable of micro processing may also be used, but the semiconductor equipment is very expensive, and is difficult to perform the process by the unit of the nano which is very small. Unlike this, in the manufacturing process of the DNA analysis device100according to an example embodiment of the present disclosure, when the nano wire layer NW is formed, the radiation speed is adjusted to form the middle portion of the nano wire layer NW to be disconnected relatively thinly. Thereafter, when the high current is applied to the nano wire layer NW, a middle portion which is formed thin and has a high resistance may be disconnected, and the nano wire layer NW may be separated into a pair of tip electrodes115. Therefore, the nano wire layer NW may be easily formed into a pair of tip electrodes115having the nano gap G without the expensive and complicated semiconductor equipment.

The DNA analysis device100according to an example embodiment of the present disclosure may easily adjust the nano gap G of the nano wire even after a manufacturing process of the DNA analysis device100is completed. The nano gap G formed in the process of disconnecting the middle portion of the nano wire layer NW by applying the high current is formed to be different from a designed numerical value, which may lead to a defect of the DNA analysis device100. However, the DNA analysis device100according to an example embodiment of the present disclosure is capable of adjusting the nano gap G by a scheme of deforming the photosensitive organic layer112even after the nano gap G is formed. Therefore, the nano gap G may be adjusted without a limitation to a process error upon forming the nano gap G, and the reliability of the DNA analysis device100may be enhanced.

FIGS.6,7and8are cross-sectional views of the main body of the DNA analysis device according to various example embodiments of the present disclosure. DNA analysis devices600,700, and800of respectiveFIGS.6to8are different from the DNA analysis device100inFIGS.1to2Cin terms of photosensitive organic layers612,712, and812, and the DNA analysis devices600,700, and800are substantially the same as the DNA analysis device100in terms of other components, so a redundant description is omitted.

Referring toFIGS.6to8, the photosensitive organic layers612,712, and812of the DNA analysis devices600,700, and800according to various example embodiments of the present disclosure may be variously designed.

First, referring toFIG.6, in the DNA analysis device600according to another example embodiment of the present disclosure, the photosensitive organic layer612may be disposed only in a part of the substrate111. The photosensitive organic layer612is not disposed in the entirety of the substrate111, but may be disposed only at a part of the substrate111corresponding to the groove113aof the insulating layer113. Therefore, the photosensitive organic layer612is formed only at a part of the main body610instead of forming the photosensitive organic layer612in the entirety of the main body610to easily adjust the nano gap G. For example, as depicted inFIG.6, the photosensitive organic layer612may not fully overlap the tip electrodes115and instead may partially overlap the tip electrodes115along the X-axis direction. The photosensitive organic layer612may fully overlap the groove113aalong the X-axis direction.

Referring toFIG.7, in the DNA analysis device700according to yet another example embodiment of the present disclosure, the photosensitive organic layer712may be disposed at one side of the groove113a, such that the photosensitive organic layer712is disposed adjacent to one sensing electrode of the pair of sensing electrodes SE. The photosensitive organic layer712may be disposed in a symmetric structure around the groove113aor may be disposed in an asymmetric structure around the groove113a. If the photosensitive organic layer712is disposed in the symmetric structure as inFIG.6, the nano gap G may be adjusted by a scheme of adjusting locations of both of a pair of sensing electrodes SE when the photosensitive organic layer712is deformed. On the contrary, if the photosensitive organic layer712of the asymmetric structure is disposed in the main body710, the location of only one electrode adjacent to the photosensitive organic layer712of a pair of sensing electrodes SE is adjusted to adjust the nano gap G when the photosensitive organic layer712is deformed. Therefore, the photosensitive organic layer712is disposed in the asymmetric structure to adjust the nano gap G. It should be understood that “adjacent” includes the meaning that one element is on the same side as another element. For example, the photosensitive organic layer712depicted inFIG.7is on the same side of the groove113aas one of the sensing electrodes SE. Similarly, the photosensitive organic layer712depicted inFIG.7may be said to be “not adjacent” to the other sensing electrode SE on the other side of the groove113a.

Referring toFIG.8, in the DNA analysis device800according to yet another example embodiment of the present disclosure, the photosensitive organic layer812may be constituted by or include a plurality of sub photosensitive organic layers812a. The plurality of sub photosensitive organic layers812ais disposed on the substrate111to deform only a part of the main body810or deform the entirety of the main body810. Therefore, the nano gap G may be more precisely adjusted through the plurality of sub photosensitive organic layers812a.

Therefore, in the DNA analysis devices600,700, and800according to various example embodiments of the present disclosure, the photosensitive organic layers612,712, and812are variously designed to adjust the nano gap G. For example, referring toFIG.6, the photosensitive organic layer612is partially formed only at a partial region of the main body610to adjust the nano gap G. In this case, since at least a part of the photosensitive organic layer612overlaps with the groove113a, the stress is concentrated on the groove113ato easily bend the main body610when the photosensitive organic layer612is deformed. Referring toFIG.7, the photosensitive organic layer712is disposed in the asymmetric structure to adjust the nano gap G. In this case, as the photosensitive organic layer712is disposed at one side of the groove113a, direct irradiation of the light to the groove113aportion is minimized or reduced to minimize or reduce noise upon DNA analysis. Further, even though the photosensitive organic layer712is disposed in the asymmetric structure, the photosensitive organic layer712is disposed adjacent to the groove113a, so the main body710may be easily bent. Referring toFIG.8, a plurality of sub photosensitive organic layers812ais disposed on the substrate111to deform the main body810in various forms. For example, the light is irradiated to only some sub photosensitive organic layers812aamong the plurality of sub photosensitive organic layers812ato change the nano gap G relatively slightly, and the light is irradiated to all sub photosensitive organic layers812ato change the nano gap G relatively much. Therefore, in the DNA analysis devices600,700, and800according to various example embodiments of the present disclosure, the photosensitive organic layers612,712, and812may be designed variously.

FIG.9Ais a plan view of the main body of the DNA analysis device according to another example embodiment of the present disclosure.FIG.9Bis a cross-sectional view of the main body of the DNA analysis device according to yet another example embodiment of the present disclosure. The DNA analysis device900ofFIGS.9A and9Bis different from the DNA analysis device100inFIGS.1to2Conly in terms of photosensitive organic layer912, and the DNA analysis device900is substantially the same as the DNA analysis device100in terms of other components, so a redundant description is omitted.

Referring toFIGS.9A and9B, the photosensitive organic layer912includes a first photosensitive organic layer912aand a second photosensitive organic layer912b. The first photosensitive organic layer912aand the second photosensitive organic layer912bmay be disposed spaced apart from each other on the substrate111. The first photosensitive organic layer912amay be disposed at one side of the groove113a, and the second photosensitive organic layer912bmay be disposed at the other side of the groove113a. For example, the first photosensitive organic layer912amay overlap with one sensing electrode SE and the second photosensitive organic layer912bmay overlap with the remaining sensing electrode SE. As shown inFIGS.9A and9B, the first photosensitive organic layer912aand the second photosensitive organic layer912bmay be disposed on the same plane (layer).

The first photosensitive organic layer912ais deformed in the X-axis direction in order to adjust the nano gap G between the sensing electrodes SE. The first photosensitive organic layer912amay be expanded or contracted in the X-axis direction by reacting to only the light linearly polarized in the X-axis direction. A photosensitive material112mof the first photosensitive organic layer912amay be aligned to react to only the light linearly polarized in the X-axis direction. Therefore, when the first photosensitive organic layer912ais expanded, the main body910may be bent based on the groove113a, and the nano gap G between a pair of sensing electrodes SE may be adjusted.

The second photosensitive organic layer912bis deformed in the Y-axis direction in order to align a pair of tip electrodes115with each other. The second photosensitive organic layer912bmay be expanded or contracted in the Y-axis direction by reacting to only the light linearly polarized in the Y-axis direction. The photosensitive material112mof the second photosensitive organic layer912bmay be aligned to react to only the light linearly polarized in the Y-axis direction. When the second photosensitive organic layer912bis deformed, a part of the main body910may be bent in the Y-axis direction, and one tip electrode115which overlaps with the second photosensitive organic layer912bmay move in the Y-axis direction. Therefore, by moving one tip electrode115in the Y-axis direction by deforming the second photosensitive organic layer912b, the locations of a pair of tip electrodes115may be adjusted so that a pair of tip electrodes115are disposed on the same line (e.g., along the X-axis direction).

Meanwhile, although not illustrated in the figure, the light irradiation unit120may include a polarizer123that provides the light linearly polarized in the X-axis direction to deform the first photosensitive organic layer912aand a polarizer123that provides the light linearly polarized in the Y-axis direction to deform the second photosensitive organic layer912b.

In the DNA analysis device900according to yet another example embodiment of the present disclosure, the tip electrodes115may be aligned with each other, and at the same time, the nano gap G may also be adjusted. First, the first photosensitive organic layer912adeformed (e.g., expanded or contracted) in the longitudinal direction of a pair of sensing electrodes SE is disposed to adjust the nano gap G between the sensing electrodes SE. The first photosensitive organic layer912ais deformed in the longitudinal direction of the sensing electrode SE to adjust the size of the nano gap G. However, if a pair of tip electrodes115are not disposed on the same line, but disposed to cross each other even though the nano gap G is adjusted, the DNA analysis may be difficult. Therefore, the second photosensitive organic layer912bcontrolling the location of the tip electrode115may be further disposed so that a pair of tip electrodes115are disposed on the same line with the nano gap G. The second photosensitive organic layer912bis deformed in a direction perpendicular to the longitudinal direction of a pair of electrodes to adjust the location of any one tip electrode115of a pair of tip electrodes115. For example, the location of one tip electrode115may be adjusted so that one tip electrode115is disposed on the same line as the other tip electrode115by expanding one end or the other end of the second photosensitive organic layer912b. Accordingly, the DNA analysis device900according to yet another example embodiment of the present disclosure includes the first photosensitive organic layer912acontrolling the nano gap G and the second photosensitive organic layer912baligning the tip electrode115to enhance DNA analysis accuracy.

FIG.10Ais a plan view of the main body of the DNA analysis device according to yet another example embodiment of the present disclosure.FIG.10Bis a cross-sectional view of the main body of the DNA analysis device according to yet another example embodiment of the present disclosure. The DNA analysis device1000ofFIGS.10A and10Bis different from the DNA analysis device900inFIGS.9A to9Bonly in terms of an insulating layer1013, and the DNA analysis device1000is substantially the same as the DNA analysis device900in terms of other components, so a redundant description is omitted.

Referring toFIGS.10A and10B, the photosensitive organic layer1012includes a first photosensitive organic layer1012aand a second photosensitive organic layer1012b, and the insulating layer1013includes a first insulating layer1013aand a second insulating layer1013b. The first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay be disposed on different layers. The first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay be disposed with the insulating layer1013interposed therebetween.

Specifically, the second photosensitive organic layer1012bmay be disposed on the substrate111, and the first insulating layer1013amay be disposed on the second photosensitive organic layer1012b. The second photosensitive organic layer1012bmay be disposed to overlap with the groove113a.

In addition, the first photosensitive organic layer1012amay be disposed on the first insulating layer1013a, and the second insulating layer1013bmay be disposed on the first photosensitive organic layer1012a. The first photosensitive organic layer1012amay be disposed to overlap with the groove113a.

In this case, both the first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay overlap with the groove113a. In this case, even though the linearly polarized light is irradiated to the groove113a, the first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay be independently deformed according to the polarization direction. For example, when the light linearly polarized in the X-axis direction is irradiated to the groove113aof the main body1010, only the first photosensitive organic layer1012amay be deformed by reacting to the linearly polarized light, and the second photosensitive organic layer1012bmay maintain the existing state. For example, when the light linearly polarized in the Y-axis direction is irradiated to the groove113aof the main body1010, only the second photosensitive organic layer1012bmay be deformed by reacting to the linearly polarized light, and the first photosensitive organic layer1012amay maintain the existing state. For example, when both the light linearly polarized in the X-axis direction and the light linearly polarized in the Y-axis direction are irradiated simultaneously to the groove113aof the main body1010, both the first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay be deformed by reacting the light.

Accordingly, in the DNA analysis device1000according to yet another example embodiment of the present disclosure, the first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay be designed in various forms. The first photosensitive organic layer1012acontrolling the nano gap G and the second photosensitive organic layer1012baligning the tip electrode115may be deformed by reacting to only lights linearly polarized in different directions. For example, the first photosensitive organic layer1012amay be deformed by reacting to the light linearly polarized in the X-axis direction and the second photosensitive organic layer1012bmay be deformed by reacting to the light linearly polarized in the Y-axis direction. Therefore, even though the first photosensitive organic layer1012aand the second photosensitive organic layer1012bare disposed to overlap with each other, and the light linearly polarized in the X-axis direction or the Y-axis direction is irradiated to the overlapped portion, only any one of the first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay be deformed. Accordingly, in the DNA analysis device1000according to yet another example embodiment of the present disclosure, the first photosensitive organic layer1012aand the second photosensitive organic layer1012bmay be designed in various forms based on a point where the first photosensitive organic layer1012aand the second photosensitive organic layer1012boperate independently.

It should be understood that the embodiment ofFIGS.9A and9Bmay be combined with the embodiment ofFIGS.10A and10B. For example, the second photosensitive organic layer912bmay be disposed in a layer (or at a level) between the first photosensitive organic layer912aand the groove113a, similar to what is depicted inFIGS.10A and10B, while not overlapping each other in the Z-axis direction, which is different than what is depicted inFIGS.10A and10B.

According to an aspect of the present disclosure, there is provided a DNA analysis device. The DNA analysis device includes a substrate, a photosensitive organic layer configured to be disposed on the substrate, and expanded or contracted by reacting to light, a pair of sensing electrodes disposed on the photosensitive organic layer, and spaced apart from each other with a nano gap, and a light irradiation unit configured to irradiate the light to the photosensitive organic layer, when the photosensitive organic layer is deformed, the nano gap between the pair of sensing electrodes is varied.

Each of the pair of sensing electrodes may include a tip electrode disposed on the photosensitive organic layer, and constituted by a nano wire, and a connection electrode disposed on the tip electrode, and the DNA analysis device may further include a metallic pattern disposed between the photosensitive organic layer and the tip electrode.

The DNA analysis device may further include a control unit configured to control the pair of sensing electrodes and the light irradiation unit.

The control unit may include an analysis unit detecting a change of a current which flows on the pair of sensing electrodes when the DNA passes through the nano gap, a power supply unit applying a voltage to the pair of sensing electrodes, and a light irradiation control unit connected to the light irradiation unit.

The light irradiation unit may include a light source configured to provide the light, a digital micro mirror reflecting the light from the light source to the photosensitive organic layer, and a polarizer disposed between the digital micro mirror and the substrate, and the light may be linearly polarized by the polarizer and incident on the photosensitive organic layer.

The photosensitive organic layer may be configured to be expanded or contracted in a direction parallel to a polarization direction of light transmitting the polarizer.

The photosensitive organic layer may include a plurality of photosensitive materials, and the plurality of photosensitive materials may be aligned in the direction parallel to the polarization direction.

The DNA analysis device may further include an insulating layer disposed between the photosensitive organic layer and the pair of sensing electrodes, the insulating layer may include a groove disposed to overlap with the nano gap between the pair of sensing electrodes, and when the light is irradiated to the photosensitive organic layer, the substrate, the photosensitive organic layer, and the insulating layer may be bent around the groove and the nano gap increases.

At least a part of the photosensitive organic layer may be disposed to overlap with the groove.

The photosensitive organic layer may be disposed further adjacent to one sensing electrode of the pair of sensing electrodes.

The photosensitive organic layer may include a plurality of sub photosensitive organic layers.

The photosensitive organic layer may include a first photosensitive organic layer configured to be expanded or contracted in a longitudinal direction of the pair of sensing electrodes, and a second photosensitive organic layer configured to be expanded or contracted in a direction perpendicular to the longitudinal direction.

When light linearly polarized in the longitudinal direction is irradiated to the photosensitive organic layer, the first photosensitive organic layer may be expanded in the longitudinal direction, and the substrate, the first photosensitive organic layer, and the insulating layer are bent around the groove.

When light linearly polarized in the direction perpendicular to the longitudinal direction is irradiated to the photosensitive organic layer, the second photosensitive organic layer may be expanded in the direction perpendicular to the longitudinal direction, and a location of each of the pair of sensing electrodes is varied.

The first photosensitive organic layer and the second photosensitive organic layer may be disposed on the same plane.

The second photosensitive organic layer may be disposed on the substrate, and the first photosensitive organic layer may be disposed on the second photosensitive organic layer, and the insulating layer may include a first insulating layer disposed between the first photosensitive organic layer and the second photosensitive organic layer, and a second insulating layer disposed between the pair of sensing electrodes and the first photosensitive organic layer.