KR20170003507A - Method for forming stacked graphene pattern - Google Patents

Abstract

The present invention relates to a method for forming a stacked graphene pattern. The method for forming a stacked graphene pattern includes the steps of: forming a metal thin film pattern; forming a graphene pattern on a base substrate; and forming the stacked graphene pattern by alternatively forming the metal thin film pattern, depositing a graphene layer on the metal thin film pattern, and evaporating the metal thin film pattern two or more times. The present invention can form the graphene pattern with a desirable shape.

Description

[0001] METHOD FOR FORMING STACKED GRAPHENE PATTERN [0002]

The present invention relates to a method for forming a laminated pattern of graphene.

Graphene is a material composed of two-dimensional bonds of carbon atoms, and unlike graphite, it is thinly formed into a single layer or several layers. Since such graphene is flexible and has a very high electrical conductivity and is transparent, studies are underway to use it as a material for a transparent and bent electrode or as an electron transfer material such as an electron transport layer in an electronic device.

Graphene has fast electron mobility and long average free path. At room temperature, the maximum electron mobility of graphene is 200,000 cm / Vs, which is 100 to 200 times faster than silicon, which is very useful as a high-performance semiconductor material. This is because graphene has a very small scattering disturbance when electrons move, which leads to a long average free path. Therefore, it exhibits a resistance value lower by 35% than copper having a very low resistance.

Graphene has attracted considerable attention as an electron transport layer and a transparent electrode of an electronic device using a photovoltaic power principle that receives light and converts it into electricity, such as a solar cell or a photodetector. ITO and the like are widely used as transparent electrodes of electronic devices. However, due to the increase in price of main materials and the possibility of depletion, manufacturing costs are increasing, and since they are not flexible, they are difficult to apply to bent devices.

In order to actually apply graphene to device manufacturing or the like, it is necessary to form a pattern using graphene. Regarding the production of such a pattern of graphene, there have been studies such as "a process for producing a graphene film and a pattern (Korea Patent Publication No. 2013-0027195) ".

However, conventionally, a graphene layer is generally formed, a mask is formed on the graphene layer, a wet or dry etching process is applied to form a graphene pattern along the pattern of the mask , And then a mask is finally removed to obtain a graphene pattern.

However, since the method of forming such a graphene pattern requires many complicated steps, it is expensive and has a high possibility of deteriorating the characteristics of the graphene itself in the pattern formation process, and it is difficult to obtain reproducibility, so that a high performance graphene pattern is formed There was a limit. In addition, a technique of growing a graphene having a constant thickness and a technique of etching a predetermined amount of graphene to a desired portion have not been developed yet. Therefore, development of a graphene pattern forming technique capable of precisely controlling thickness and shape is required It is true.

The present invention aims to provide a method of forming a graphene laminate pattern capable of forming a graphene pattern of a desired shape by laminating a desired thickness of a graphene layer on a desired portion of the substrate.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to a first aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a metal thin film pattern on a substrate; Depositing a graphene layer on the metal thin film pattern and evaporating the metal thin film pattern to form a graphene pattern on the substrate; And forming the metal thin film pattern and depositing the graphene layer on the metal thin film pattern alternately to form a laminate pattern of graphene. have.

According to one embodiment of the present invention, graphene can be laminated to a desired portion of a substrate to a desired thickness to form a desired graphene pattern. In addition, according to one embodiment of the present invention, the layer thickness of the graphene pattern can be partially controlled, and unlike the conventional multi-layer graphene having several layers or several tens of layers of irregularly stacked layers from one layer, A graphene laminated pattern having a number of layers and an adjustable thickness can be produced.

1 is a flowchart for explaining a method of forming a graphene laminated pattern according to an embodiment of the present invention.
FIGS. 2A to 2D are cross-sectional views for explaining respective steps of a graphening method according to an embodiment of the present invention.
FIGS. 3A to 3E are schematic views for explaining each step of the method for forming a graphene laminated pattern according to an embodiment of the present invention. FIG.
4 is an image showing the TEM (transmission electron microscopic) diffraction pattern analysis result of the single-layer graphene according to the comparative example of the present application.
5 is an image showing the result of analysis of a TEM diffraction pattern of graphene deposited according to an embodiment of the present invention.
Figure 6 is an optical image of a partially stacked graphene according to one embodiment of the invention.
FIGS. 7A and 7B show Raman spectrum analysis results of the single-layer graphene according to the comparative example of the present invention and the stacked graphene according to one embodiment of the present invention, respectively.
8 is a graph showing the transmittance of laminated graphene measured according to an embodiment of the present invention.
9 is an optical microscope image of a graphene laminated pattern according to an embodiment of the present invention.
10A is a schematic view of a check pattern graphene laminate pattern forming method according to an embodiment of the present invention.
FIGS. 10B and 10C are optical microscope images of a check patterned graphene laminated pattern according to an embodiment of the present invention. FIG.
10D shows a Raman spectrum of check pattern graphene stacked according to one embodiment of the present invention.
11 is a schematic diagram of a graphene lamination growth method for a graphene pattern in one embodiment of the present invention.
12A to 12E are TEM images of a graphene pattern laminated from one to five layers, respectively, in one embodiment of the present invention.

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. It should be understood, however, that the present invention may be embodied in many different forms and is not limited to the embodiments and examples described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is "on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise.

As used herein, the terms "about," " substantially, "and the like are used herein to refer to or approximate the numerical value of manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to prevent unauthorized exploitation by unauthorized intruders of the mentioned disclosure.

The term " step " or " step of ~ " as used throughout the specification does not imply " step for.

Throughout this specification, the term "combination (s) thereof " included in the expression of the machine form means a mixture or combination of one or more elements selected from the group consisting of the constituents described in the expression of the form of a marker, Quot; means at least one selected from the group consisting of the above-mentioned elements.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B".

Throughout this specification, the term "graphene " means that a plurality of carbon atoms are linked together by a covalent bond to form a polycyclic aromatic molecule, wherein the carbon atoms linked by the covalent bond are 6-membered rings A 5-membered ring, and / or a 7-membered ring. Thus, the sheet formed by the graphene may be viewed as a single layer of carbon atoms covalently bonded to each other, but may not be limited thereto. The sheet formed by the graphene may have various structures, and the structure may vary depending on the content of the 5-membered ring and / or the 7-membered ring which may be contained in the graphene. When the sheet formed by the graphene is a single layer, they may be laminated to form a plurality of layers, and the side end portion of the graphene sheet may be saturated with hydrogen atoms, but the present invention is not limited thereto.

Hereinafter, embodiments of the present invention are described in detail, but the present invention is not limited thereto.

According to a first aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a metal thin film pattern on a substrate; Depositing a graphene layer on the metal thin film pattern and evaporating the metal thin film pattern to form a graphene pattern on the substrate; And forming the metal thin film pattern and depositing the graphene layer on the metal thin film pattern alternately to form a laminate pattern of graphene. have.

For example, depositing a graphene layer on the metallic thin film pattern may be, but not limited to, depositing a single layer of graphene layer. For example, the deposition of the single-layer graphene layer may be performed using a metal thin film pattern including copper (Cu), but the present invention is not limited thereto.

When a graphene layer is formed by incorporating copper into the metal thin film pattern, since a single layer of graphene is uniformly formed on the metal thin film pattern, the number of graphene layers deposited can be precisely controlled, But may not be limited thereto. For example, the graphenes stacked herein may include, but are not limited to, graphene layers that are stably stacked and uniformly stacked by AB stacking. The AB stacking refers to a structure of a plurality of layers of graphenes generally known in the art.

For example, the metal thin film pattern can be formed by using a patterning method commonly used in the art without limitation.

For example, to form the metal thin film pattern, a shadow mask in which a hole is partially formed is used to exclude a part of the substrate, and then a metal is evaporated to form a metal thin film pattern, But may also be, but not limited to, selectively depositing metal. For example, the metal thin film pattern may be formed using a lithography method, but the present invention is not limited thereto. For example, the lithographic method may include, but is not limited to, first and then lithographically depositing a metal thin film, followed by dry etching or wet etching the metal thin film.

For example, the metal thin film pattern and the deposition of the graphene layer on the metal thin film pattern may be alternately performed two or more times to form a laminated pattern of graphene, but the present invention is not limited thereto have. For example, the metal thin film pattern and the deposition of the graphene layer on the metal thin film pattern may be alternately performed several times to several tens of times to form a laminate pattern of graphene. However, .

For example, the formation of the metal thin film pattern and the deposition of the graphene layer on the metal thin film pattern may be performed twice to 100 times, 2 times to 80 times, 2 times to 60 times, 2 times to 40 times, 2 to 20 times, 2 to 10 times, 2 to 5 times, 10 to 100 times, 20 to 100 times, 40 to 100 times, 60 to 100 times, or 80 to 100 times A laminated pattern of graphenes may be formed, but the present invention is not limited thereto.

For example, when the metal thin film pattern is formed and the graphene layer is deposited on the metal thin film pattern alternately two or more times, a single layer of graphene is stacked in layers of several tens, Layer, or several hundred layers or more, but may not be limited thereto.

For example, the method for forming a laminated pattern of graphenes of the present application includes the steps of: forming a graphene layer on a substrate; Forming a metal thin film on the graphene layer; And forming a graphene layer on the metal thin film. In the step of forming the graphene layer on the metal thin film, the metal thin film is evaporated. However, , But may not be limited thereto. For example, the graphene layer formed on the substrate and the graphene layer formed on the metal thin film may be in contact with each other due to evaporation of the metal thin film, but the present invention is not limited thereto.

For example, the substrate may include, but is not limited to, graphene formed on the substrate.

FIG. 1 is a flow chart for explaining a method of forming a graphene laminate pattern according to a first aspect of the present invention, and FIGS. 2 (a) to 2 (d) are sectional views for explaining a method of laminating graphene according to an embodiment of the present invention.

3A to 3E are schematic views for explaining a method of forming a graphene laminated pattern according to an embodiment of the present invention.

Hereinafter, a method of laminating graphene according to an embodiment of the present invention will be described in detail with reference to FIGS. 2A to 2D and FIGS. 3A to 3E, but the present invention is not limited thereto.

According to an embodiment of the present invention, the method of laminating the graphene layer includes forming a metal catalyst layer 130 on the substrate 110 (see FIG. 2A), forming a graphene layer 150 on the metal catalyst layer 130 A metal thin film 170 is formed on the graphene layer 150 and then a graphene layer is formed on the metal thin film 170 to form the metal thin film 170, The conventional graphene layer formed on the metal catalyst layer 130 and the newly formed graphene layer may be laminated to form the graphene laminate 190 (FIG. 2D).

For example, by forming the metal thin film 170 on the graphene layer 150 in the form of a pattern, the graphene layer 170 formed on the metal thin film 170 may be patterned But the present invention is not limited thereto.

According to one embodiment of the present invention, the method of forming a graphene laminate pattern of the present invention includes the steps of forming a single-layer graphene 152 (FIG. 3A), forming a metallic thin film pattern 172 on the single- , The metallic thin film pattern is evaporated by depositing a graphene layer on the metallic thin film pattern 172, and graphenes are stacked on the single-layer graphene 152 to form a two-layer graphene 154 The metal thin film pattern 172 is evaporated by evaporating a graphene layer on the metal thin film pattern 172 to form the single layer graphene 152, (FIG. 3E), which includes a two-layer graphene 154 and a stacked three-layer graphene 165 (FIG. 3E).

According to one embodiment of the present disclosure, the graphene laminate pattern of the present invention may be formed in a check pattern, but the present invention is not limited thereto.

FIG. 10A is a schematic view showing a process of forming a check pattern of the graphene laminate pattern, and FIG. 11 is a schematic view showing a graphene pattern process of forming a graphene pattern.

In the check patterned graphene laminate pattern forming method, for example, a single layer of graphene is grown on a metal substrate by CVD or the like, and then a metal thin film is deposited horizontally to form a check pattern (A) in FIG. 10A), graphene is grown again using CVD to form a two-layered horizontal graphene pattern (FIG. 10A) , And the process of growing the graphene again using CVD (FIG. 10A (d)) may be alternatively performed to form the check patterned graphene laminate pattern, but the present invention is not limited thereto.

The graphene laminate pattern forming method is a method in which graphene is firstly grown on a metal substrate (Fig. 11 (a)), and a method such as thermal evaporation is applied on a metal substrate on which graphene is grown (FIG. 11 (b)). In order to grow graphene in a second order, graphene is deposited on the substrate on which the metal thin film is deposited by CVD or the like (FIG. 11 (c) A graphene laminate pattern may be formed, but the present invention is not limited thereto.

According to one embodiment of the present invention, the graphene laminate pattern forming method may include, but is not limited to, forming graphene patterns having different shapes from each other on the substrate.

For example, when the metal thin film pattern is formed and the graphene layer is deposited on the metal thin film pattern, if different metal thin film patterns are used, The overlapping portions of the metal thin film patterns may be multilayer graphenes, and the non-overlapping portions may be single layer graphenes, but the present invention is not limited thereto.

The graphene pattern is not limited to its type or shape. For example, a graphene mesh or a graphene can be formed by a method of forming a graphene laminate pattern according to the present invention, But may not be limited thereto. For example, the graphene grating may be used as an optical filter, but may not be limited thereto.

For example, the method of forming a graphene laminate pattern of the present invention may include, but not limited to, laminating graphene patterns having the same shape on the substrate. For example, in the case of forming a graphene laminate pattern by laminating graphene patterns having the same shape on the substrate, by adjusting the number of lamination of the graphene patterns, the desired pattern, the desired number of graphene layers, A graphene pattern having a graphene thickness can be formed, but the present invention is not limited thereto.

For example, the metal thin film pattern may be formed by atomic layer deposition (ALD), sputtering, thermal evaporation, e-beam evaporation, molecular beam epitaxy (MBE) ), Pulsed laser deposition (PLD), chemical vapor deposition (CVD), sol-gel methods, and combinations thereof. But may not be limited thereto.

For example, the deposition of the graphene layer on the metal thin film pattern can be performed by using a method commonly used for graphen growth in the art without any particular limitation. For example, the method may include, but is not limited to, a method of coating an organic material such as PMMA on the metal thin film pattern, and then annealing in an atmosphere containing hydrogen to grow graphene.

According to one embodiment of the present invention, the deposition of the graphene layer on the metal thin film pattern may be performed by a chemical vapor deposition (CVD) method, but the present invention is not limited thereto.

According to one embodiment of the present invention, the chemical vapor deposition process is performed by rapid thermal chemical vapor deposition (RTCVD), inductively coupled plasma-chemical vapor deposition (ICP-CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor deposition vapor deposition (PECVD), combinations thereof, and the like, but the present invention is not limited thereto.

According to an embodiment of the present invention, the chemical vapor deposition method may be performed at a temperature ranging from about 300 ° C to about 2,000 ° C, but is not limited thereto.

For example, the chemical vapor deposition process may be performed at a temperature of from about 300 ° C to about 2,000 ° C, from about 500 ° C to about 2,000 ° C, from about 800 ° C to about 2,000 ° C, from about 1,000 ° C to about 2,000 ° C, About 300 ° C to about 1,500 ° C, about 300 ° C to about 1,000 ° C, about 300 ° C to about 800 ° C, about 800 ° C to about 1,300 ° C, or about 800 ° C to about 1,000 ° C, But may not be limited thereto.

For example, depositing the graphene layer may include, but is not limited to, providing and reacting a reaction gas and heat comprising a carbon source on the metal thin film pattern. For example, the carbon source can be selected from the group consisting of carbon monoxide, carbon dioxide, methane, ethane, ethylene, ethanol, acetylene, propane, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene, But it is not limited thereto. For example, when the carbon source is heat-treated at a temperature of about 300 ° C. to about 2,000 ° C. while supplying the gaseous phase, carbon components present in the carbon source are combined to form a hexagonal plate-like structure, But may not be limited thereto. For example, the heat treatment may be performed at a temperature of about 300 캜 to about 2,000 캜, about 500 캜 to about 2,000 캜, about 700 캜 to about 2,000 캜, about 900 캜 to about 2,000 캜, But is not limited to, performing at temperatures of from about 2,000 DEG C to about 300 DEG C to about 1,500 DEG C, from about 300 DEG C to about 1,200 DEG C, from about 300 DEG C to about 900 DEG C, or from about 300 DEG C to about 500 DEG C .

For example, the formation of the graphene layer on the metal thin film pattern may be performed under atmospheric pressure, low pressure, or vacuum, but is not limited thereto. For example, when performing the process of growing the graphene layer under atmospheric pressure, the damage of graphene caused by collision with heavy argon at a high temperature can be minimized by using helium or the like as a carrier gas, But may not be limited. In addition, when the above process is performed under atmospheric pressure, large area graphene can be manufactured by a simple process at a low cost. For example, when the process is performed under a low pressure or a vacuum condition, it is possible to synthesize high-quality graphene by using hydrogen gas as the atmospheric gas and reducing the oxidized surface of the metal catalyst by increasing the temperature Advantage, but may not be limited thereto.

According to one embodiment of the present application, the substrate may be one comprising silicon, graphene, glass, quartz, oxygen, carbon felt, sapphire, silicon nitride, silicon carbide, silicon oxide, titanium coated substrate, ceramic, metal, But may not be limited thereto.

For example, the substrate may include, but is not limited to, graphene formed on the substrate. For example, the substrate may include, but is not limited to, graphene formed on the metal catalyst layer. For example, the metal catalyst layer is formed to facilitate growth of graphene, and graphene may be grown on the surface of the metal catalyst layer.

For example, the metal catalyst layer may include at least one of Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, Ge, but are not limited to, one or more metals or alloys selected from the group consisting of brass, bronze, white brass, stainless steel, and combinations thereof. The thickness of the metal catalyst layer is not particularly limited and may be a thin film or a thick film.

For example, the metal catalyst layer may be formed by atomic layer deposition (ALD), sputtering, thermal evaporation, e-beam evaporation, molecular beam epitaxy (MBE) , Pulsed laser deposition (PLD), chemical vapor deposition (CVD), sol-gel methods, and combinations thereof. However, the present invention is not limited thereto.

For example, the formation of graphene on the metal catalyst layer can be performed by using a method that is commonly used for graphen growth in the art without any particular limitation, and according to one embodiment of the present invention, A chemical vapor deposition (CVD) method may be used, but the present invention is not limited thereto. For example, the chemical vapor deposition process may be performed by rapid thermal chemical vapor deposition (RTCVD), inductively coupled plasma-chemical vapor deposition (ICP-CVD), or low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), and plasma-enhanced chemical vapor deposition (PECVD) ), Combinations thereof, and the like, but the present invention is not limited thereto. For example, the method may include, but is not limited to, a method in which an organic material such as PMMA is coated on the metal catalyst layer and then annealed in an atmosphere containing hydrogen to grow graphene.

For example, forming graphene on the metal catalyst layer may be, but not limited to, forming a single layer of graphene. For example, forming the single-layer graphene may be performed using a metal catalyst layer comprising Cu (copper), but may not be limited thereto. For example, when Cu is used as a metal catalyst layer to form a graphene layer, a single layer of graphene may be uniformly formed on the metal catalyst layer, but the present invention is not limited thereto.

For example, the graphene layer may be transferred onto a substrate, but may not be limited thereto.

The graphene layer may be formed using any method commonly used for graphene growth in the art without any particular limitation. For example, the graphene layer may be formed by a chemical vapor deposition (CVD) method, an epitaxy method, Or may be formed by a mechanical peeling method, but the present invention is not limited thereto.

The transfer of the graphene layer can be carried out using any method normally used for transferring the graphene layer in the art without limitation. For example, the transfer of the graphene layer may be performed by wet transfer or dry transfer, but may not be limited thereto. For example, the transfer of the graphene layer may be performed by using PDMS, PMMA, or heat-releasing tape, or by using a roll, but may not be limited thereto.

For example, transferring the graphene layer onto the substrate may include, but is not limited to, transferring a single layer of graphene.

According to one embodiment of the present invention, the thickness of the metal thin film pattern may be about 10 nm to about 100 nm, but is not limited thereto. For example, the thickness of the metal thin film pattern may be from about 10 nm to about 100 nm, from about 10 nm to about 80 nm, from about 10 nm to about 50 nm, from about 10 nm to about 30 nm, from about 30 nm to about 100 nm , From about 50 nm to about 100 nm, from about 80 nm to about 100 nm, or from about 40 nm to about 60 nm, but may not be limited thereto. For example, when the thickness of the metal thin film pattern is less than about 10 nm, the graphene layer may not normally grow on the metal thin film pattern, but the present invention is not limited thereto. For example, when the thickness of the metal thin film pattern is greater than about 100 nm, the metal thin film pattern is not sufficiently evaporated during the growth of the graphene layer by chemical vapor deposition, so that the graphene layer is not sufficiently in contact with the substrate But may not be limited thereto.

According to an embodiment of the present invention, the metal thin film pattern may be formed of a metal thin film pattern such as Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, But are not limited to, one or more metals or alloys selected from the group consisting of Ge, Brass, Bronze, Baux, Stainless Steel, and combinations thereof. have.

For example, the metal thin film pattern may be the same as or similar to the metal catalyst layer in the growth of graphene, but may not be limited thereto.

According to an embodiment of the present invention, the metal thin film pattern may be formed by atomic layer deposition (ALD), sputtering, thermal evaporation, e-beam evaporation, molecular beam deposition by a method selected from the group consisting of beam epitaxy (MBE), pulsed laser deposition (PLD), chemical vapor deposition (CVD), Sol-Gel methods, But it is not limited thereto.

According to one embodiment of the present invention, the graphene layer may be formed at atmospheric pressure, low pressure, or vacuum, but may not be limited thereto.

The graphene laminate pattern manufactured according to one embodiment of the present invention may be used for manufacturing a thin film transistor, a memory device, a transparent electrode, a photodetector, a semiconductor device, or a light emitting diode, but the present invention is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[Example]

Form a graphene layer on a substrate

The copper foil at a temperature condition of 980 ℃ under hydrogen gas atmosphere (200 sccm) 10 bungan annealing a rear, methane (CH ₄₎ and hydrogen gas is 150 sccm for existing 30 minutes by a chemical vapor deposition process in an atmosphere of a 200 sccm Graphene was grown on the copper foil to form a graphene layer.

Lamination of graphene by chemical vapor deposition process

A 50 nm thick copper thin film was deposited on the graphene layer using a thermal deposition method.

Thereafter, a graphene layer was grown on the copper thin film by a chemical vapor deposition process in an atmosphere in which methane and hydrogen gas were present at 150 sccm to 200 sccm at 980 ° C. At this time, the copper thin film was evaporated by a high-temperature heat treatment applied during chemical vapor deposition, and the existing graphene layer and the newly grown graphene layer were contacted and laminated.

Lamination pattern formation of graphene

A graphene layer was formed on the copper foil by the same method as in the above examples. Then, a copper thin film pattern was formed on the graphene layer at a portion to be laminated. Specifically, a shadow mask was placed on the graphene and then punctured in the shadow mask at a pressure of 3.0 × 10 ^-6 torr using thermal evaporation equipment and 99.997% copper pellets To form a copper thin film pattern. The thickness of the deposited copper film was less than about 100 nm.

On the copper thin film pattern, graphene was deposited by a chemical vapor deposition method in the same manner as in the above example. The deposition rate was 600 ℃ / min when the chemical vapor deposition method was used and the deposition was performed at 980 ℃. Annealing conditions were 10 minutes at 980 占 폚 under a 200 sccm atmosphere of 99.999% hydrogen, 10 minutes at 980 占 폚 under an atmosphere of 99.999% methane at 150 sccm and 99.999% hydrogen at 200 sccm during graphene growth. In this process, the copper thin film pattern evaporates and disappears, and a graphene layer is further grown at the position where the copper thin film is located, and is laminated with the existing graphene layer to form a graphene laminate pattern.

Forming a copper thin film pattern on the graphene laminate pattern using an additional shadow mask; depositing graphene on the copper thin film pattern by a chemical vapor deposition method to evaporate the copper thin film pattern; Thereby forming a graphene laminated pattern.

Diffraction pattern analysis of stacked graphene

In this embodiment, the diffraction pattern of the graphene laminated with the single-layer graphene was analyzed using a transmission electron microscope (TEM). The top image of Fig. 4 and the top image of Fig. 5 show the diffraction pattern of graphene laminated with two layers of single layer graphene, respectively. The lower graph of Fig. 4 and the lower graph of Fig. 5 show the diffraction intensities at the respective diffraction points (indicated by the arrows in the upper images of Figs. 4 and 5) of the single-layer graphene and the graphene . In the top image of FIGS. 4 and 5, the presence or absence of lamination can be determined by measuring the diffraction intensities of the four points indicated by the arrows. In the case of the single-layer graphene, the diffraction intensity at two diffraction points in the middle is higher, In the case of graphene laminated layers, the diffraction intensity of the two outer diffraction points was higher. Thus, it was confirmed that the growth of the stacked graphene was grown by AB stacking.

Confirmation of partial lamination of graphene

In this embodiment, it was observed that an additional graphene layer was laminated only on a part of the graphene. 6 is an optical microscope image of a structure in which a copper thin film is deposited only on a specific portion of graphene using a shadow mask, and then graphenes are formed on the copper thin film. Since the graphene portions stacked in FIG. 6 have a darker color than the single-layer graphene portions, it was confirmed that graphenes can be selectively deposited only at specific portions through partial metal deposition.

Raman spectral analysis of laminated graphene

In this embodiment, the Raman spectrum analysis was performed using the Raman spectroscopy of the stacked graphene. FIGS. 7A and 7B are Raman spectrum analysis results of graphene laminated with single-layer graphene and FIG. 10D are Raman spectrum analysis results of graphene laminated from one layer to three layers, respectively. And the upper graph of each of FIGS. 7A and 7B shows the results of Raman spectrum analysis of arbitrary three points in the same sample, respectively. The tables at the bottom of FIGS. 7A and 7B show results obtained by fitting Lorentz fitting results of the Raman spectrum analysis.

In Raman spectrum analysis of graphene, 2D / G ratio decreases and 2D FWHM increases as the number of graphene layers increases. In the present embodiment, the result shown in FIG. 7B shows a decrease in the 2D / G ratio and an increase in the 2D FWHM compared to the result shown in FIG. 7A. As a result, FIG.

Measurement of graphene transmission

In this embodiment, the transmittance of the stacked graphene was measured. 8 is a graph showing the transmittance of graphene laminated with two-layered graphene using UV-visible spectroscopy, and the table at the bottom shows a numerical value of the measurement result will be. The transmittance of a graphene layer is known to be about 97.7%, so that about 2.3% of light is absorbed per graphen layer. According to the measurement results, the transmittance of the single-layer graphene was about 97.9%, and the transmittance of the double-layered graphene was about 95.9%, confirming that the stacked graphenes were stacked in two layers.

Observation of graphene laminate pattern

10B shows a plan view of the graphene laminate pattern formed by this embodiment using an optical microscope before transferring it onto a substrate. The plan image is transferred onto a Si / SiO ₂ (300 nm) substrate, The planar photographs observed with use are shown in Figs. 9 and 10C. In FIG. 9, a graphene mesh formed by one embodiment of the present invention can be observed. The faint color is a one-layer (single-layer) graphene, the darkest part is a three-layer graphene, and the medium-colored part is a two-layer graphene. Specifically, graphene patterns are vertically and horizontally crossed and stacked on a single-layer graphene, so that three-layer graphene is formed at the intersection of the graphene patterns in the up-and-down and left-right directions, It was visually confirmed that the two-layer graphene was laminated.

12A to 12E are cross-sectional photographs of graphene laminated from one layer to five layers, respectively, using an electron transmission microscope. I could visually confirm that the graphene was stacked from the first floor to the fifth floor.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention .

110: substrate
130: metal catalyst layer
150: Graphene layer
152: single layer graphene
154: Two layer graphene
156: Three layer graphene
170: metal thin film
172: metal thin film pattern
190: graphene laminate

Claims (8)

Forming a metal thin film pattern having a thickness of 10 nm to 100 nm on a substrate;
Depositing a graphene layer on the metal thin film pattern by a chemical vapor deposition (CVD) method and evaporating the metal thin film pattern to form a graphene pattern on the substrate; And
Forming a metal thin film pattern having a thickness of 10 nm to 100 nm; depositing a graphene layer on the metal thin film pattern; and evaporating the metal thin film pattern two or more times, And forming a graphene laminate pattern,
Wherein the graphene layered pattern is formed by evaporating the metal thin film pattern when the graphene layer is deposited so that the deposited graphene layers are in contact with each other and stacked to form a graphene mesh or a graphene grid.
Graphene laminate pattern forming method.
The method according to claim 1,
Wherein the graphene laminate pattern forming method includes forming graphene patterns having different shapes on the substrate by being laminated.
The method according to claim 1,
The chemical vapor deposition process may be performed by rapid thermal chemical vapor deposition (RTCVD), inductively coupled plasma-chemical vapor deposition (ICP-CVD), or low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor deposition (PECVD) And combinations thereof. ≪ Desc / Clms Page number 24 >
The method according to claim 1,
Wherein the chemical vapor deposition method is performed in a temperature range of 300 캜 to 2,000 캜.
The method according to claim 1,
Wherein the substrate comprises silicon, graphene, glass, quartz, oxygen, carbon felt, sapphire, silicon nitride, silicon carbide, silicon oxide, titanium coated substrate, ceramic, metal, or plastic. .
The method according to claim 1,
The metal thin film pattern may include at least one of Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, Ge, The method of forming a graphene laminate pattern according to claim 1, wherein the at least one metal or alloy is selected from the group consisting of bronze, white copper, stainless steel, and combinations thereof.
The method according to claim 1,
The metal thin film pattern may be formed by atomic layer deposition (ALD), sputtering, thermal evaporation, e-beam evaporation, molecular beam epitaxy (MBE) Wherein the film is formed by a process selected from the group consisting of pulsed laser deposition (PLD), chemical vapor deposition (CVD), sol-gel process, and combinations thereof. Pattern formation method.
The method according to claim 1,
Wherein the graphene layer is formed under normal pressure, low pressure, or vacuum.

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