KR101437449B1 - Method for constructing laminate with graphene - Google Patents

Abstract

Disclosed is a manufacturing method of a graphene-based laminate using direct transfer. According to an embodiment of the present invention, the manufacturing method includes a first step of forming a graphene layer by growing graphene on an upper side of a metal substrate; a second step of forming a transparent conductive layer on the graphene layer; a third step of forming a cured layer by applying a resin capable of being cured by heat or UV rays on a first substrate; a fourth step of curing the cured layer with heat or UV rays after bonding the transparent conductive layer and the cured layer; and a fifth step of removing the metal substrate.

Description

[0001] METHOD FOR CONSTRUCTION LAMINATE WITH GRAPHENE [0002]

The present invention relates to a laminate manufacturing method, and more particularly, to a graphene-based laminate manufacturing method.

Flexible device technology aiming at ultra-light, low power, low cost, portability and high functionality is emerging as a core technology in the ubiquitous era, and related researches are actively conducted.

Among the various technical elements constituting the flexible element, the technical elements related to the transparent electrode material are classified as core technologies. The transparent electrode material must have a transparent and low resistance, and even when the element is bent or folded, It has a technical problem that it must have a high strength and a physical property similar to a thermal expansion coefficient of a plastic substrate so that a short circuit or a change in sheet resistance should not be large even when the device is overheated.

ITO (Indium Tin Oxide) is used as a typical transparent electrode material. In the case of ITO, the resistance and the transmittance are decreased when the thickness is increased. Therefore, it is difficult to obtain a transparency of 80% or more and a sheet resistance of 30 Ω / sq or less And there is a limitation in realizing a flexible transparent electrode having a large area since the plastic substrate is deformed when heat treatment is performed at about 200 DEG C (ITO sputtering) to obtain a low resistance. In addition, it is pointed out that the unit price of the material itself is rising due to problems such as depletion of indium.

In this situation, graphene has focused attention as an alternative to ITO. Graphene, a carbon isotope, is composed of a hexagonal honeycomb-shaped carbon monolayer, which is a bandgap-free conductor with linear energy-momentum dispersion relationships in the Fermi level group. In recent experiments, it has been found that when a transparent electrode is manufactured using graphene, a transmittance of 97% and a sheet resistance of 30 Ω / sq or less can be achieved. As a result, it is found that the graphene-based laminate, Research is expected to be more active.

At present, methods for manufacturing graphene are variously known, and among them, graphene produced by chemical vapor deposition (CVD) is the most excellent in characteristics and most suitable for mass production. However, in the case of using the chemical vapor deposition method, a transfer process in which graphenes grown on a metal are transferred to a desired substrate is required. However, such a transfer process causes problems such as a complicated process, a problem of degrading graphene properties during the process, and a difficulty of complete removal of contaminants (such as polymer residues).

The embodiments of the present invention provide a method of manufacturing a graphene-based laminate in which graphene is directly transferred to a substrate and no problem occurs during indirect transfer.

According to an aspect of the present invention, there is provided a method of manufacturing a semiconductor device, including: a first step of growing a graphene layer on a metal substrate to form a graphene layer; Forming a transparent conductive layer on the graphene layer; A third step of applying a resin cured by heat or ultraviolet rays onto the first substrate to form a cured layer; (C) bonding the transparent conductive layer and the cured layer to each other, and then curing the cured layer through heat or ultraviolet irradiation; And a fifth step of removing the metal substrate, may be provided.

At this time, the transparent conductive layer may be formed of one selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), F-doped tin oxide (FTO), antimony tin oxide (ATO), AZO ), a-IGZO (In2O3: Ga2O3: ZnO), MgIn 2 O 4, Zn 2 SnO 4, ZnSnO 3, (Ga, In) 2 O 3, Zn 2 In 2 O 5, InSn 3 O 12, In 2 O _{3, SnO 2, Cd 2 SnO} 4, CdSnO 3 and CdIn ₂ O _4, or one or more metal oxides selected from, Cu, Al, Sn, Ni , W, Ti, Cr, Co, Zn, Ta, V, Au, Ag, TiN, and Pt, or may be formed of Cu nanowires or Ag nanowires.

At this time, the cured layer may be a thermosetting layer containing a thermoplastic resin and a thermosetting agent, or may include an acrylate monomer, an acrylate oligomer and an ultraviolet curing agent.

In addition, a step of forming a protective layer on the graphene layer may be further included between the first and second steps.

The method may further include a sixth step of removing the first substrate using a roll-to-roll process and transferring the graphene layer onto a second substrate.

According to another aspect of the present invention, there is provided a graphene layer; Transparent conductive layer; Wherein the cured layer is a thermosetting layer comprising a thermoplastic resin and a thermosetting agent or a graphene-based layer that is an ultraviolet-cured layer containing an acrylate monomer, an acrylate oligomer and an ultraviolet curing agent, A laminate may be provided.

At this time, a protective layer may be formed between the graphene layer and the transparent conductive layer.

Embodiments of the present invention include a cured layer that is cured by heat or ultraviolet light on a substrate to enable direct transfer of the graphene to the substrate so that graphene- It is possible to manufacture sieves.

In addition, the graphene-based laminate manufactured by the method according to the embodiments of the present invention can form a composite layer of graphene and a transparent conductive material, thereby achieving a high transmittance and a low sheet resistance while enabling large area production.

1 to 6 are schematic views illustrating a method of manufacturing a graphene-based laminate according to an embodiment of the present invention.
7 is a view schematically showing a form in which the graphene-based laminate shown in Fig. 6 is transferred to another substrate.

A method for fabricating a graphene-based laminate according to an embodiment of the present invention includes a first step of growing a graphene layer on a metal substrate to form a graphene layer, a second step of forming a transparent conductive layer on the graphene layer, A step of applying a resin cured by heat or ultraviolet rays onto a substrate to form a cured layer; and a step of curing the cured layer by heating or ultraviolet irradiation after the transparent conductive layer and the cured layer are contacted with each other; , And removing the metal substrate (5).

The process steps of the method according to embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that each layer of the graphene-based laminate is presented herein only with reference to the accompanying drawings. That is, not only the case where only the layer referred to in this specification is made, but also the case where another layer intervenes or exists between the layers can be included in the scope of the present invention.

It is also to be understood that the expressions "above "," on ", or "on" in this specification are intended to refer to the relative positional concept relative to the attached drawings, (Particularly a surface having a three-dimensional shape), although not exclusively, that other layers or components may be intervening or present in the intervening layers, It should be noted that it may include cases that are not completely covered. Likewise, the expression "lower," " under, "or" under "may also be understood as a relative concept of the position between a particular layer (component)

1 to 6 are schematic views illustrating a method of manufacturing a graphene-based laminate according to an embodiment of the present invention.

(1) Step 1

Referring to FIG. 1, step 1 is a step of growing a grapheme on the metal substrate M to form a graphene layer 110.

The metal substrate M functions as a seed layer for growing graphene, and is not limited to a specific material. For example, the metal substrate M may be made of a metal such as silicon, Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, , Bronze, white copper, stainless steel, and Ge.

The metal substrate M may include a catalyst layer (not shown) that adsorbs carbon well to facilitate the growth of graphene. The catalyst layer is not limited to a specific material and may be formed of the same or different material as the metal base M. [ On the other hand, the thickness of the catalyst layer is not limited and may be a thin film or a thick film.

The graphene layer 110 is formed in the form of a layer or a sheet. At this time, the graphene layer 110 may be formed as a single layer or two or more layers. Also, the graphene layer 110 may be large.

As a method of forming the graphene layer 110 on the metal substrate M, CVD (Chemical Vapor Deposition) may be used. Herein, the chemical vapor deposition may be performed by a variety of methods including high temperature 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 ) Or chemical vapor deposition (PECVD), and the like.

Specifically, after a metal substrate M is placed in a furnace, a reaction gas containing a carbon source is supplied to the metal substrate M and the graphene is grown by heat treatment at a normal pressure to form a graphene layer 110 may be formed. Here, the heat treatment temperature may be 300 ° C to 2,000 ° C. As described above, the metal substrate M is reacted with the carbon source at a high temperature and a normal pressure so that an appropriate amount of carbon is melted or adsorbed in the metal substrate M, and then the carbon atoms contained in the metal substrate M are crystallized Thereby forming a graphene crystal structure.

Meanwhile, the number of layers of the graphene layer 110 can be controlled by controlling the type and thickness of the metal substrate M (including the catalyst layer), the reaction time, the cooling rate, and the concentration of the reaction gas in the above-

Examples of the carbon source include carbon monoxide, carbon dioxide, methane, ethane, ethylene, ethanol, acetylene, propane, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene, toluene, (Step 1 above).

(2) Step 2

Referring to FIG. 2, step 2 is a step of forming a transparent conductive layer 120 on the graphene layer 110.

The transparent conductive layer 120 may be formed of ITO (indium tin oxide, In ₂ O ₃ : Sn, 0? Sn? 15%), IZO (indium zinc oxide, In ₂ O ₃ : Zn, 0? Zn? 5% (F-doped tin oxide), ATO (antimony tin oxide), AZO (ZnO: Al), GZO (ZnO: Ga), a-IGZO (In2O3: Ga2O3: ZnO), MgIn 2 O 4, Zn 2 SnO 4, At least one metal selected from ZnSnO ₃ , (Ga, In) ₂ O ₃ , Zn ₂ In ₂ O ₅ , InSn ₃ O ₁₂ , In ₂ O ₃ , SnO ₂ , Cd ₂ SnO ₄ , CdSnO ₃ and CdIn ₂ O ₄ Oxide or at least one metal selected from Cu, Al, Sn, Ni, W, Ti, Cr, Co, Zn, Ta, V, Au, Ag, TiN and Pt, And any known material having both transparency and conductivity, without being limited to the above listed materials, can form the transparent conductive layer 120.

The transparent conductive layer 120 may be formed using any of the above listed materials in the form of a thin film, a nano rod, a nano dot, and a nanowire.

The thickness of the transparent conductive layer 120 may have an appropriate thickness depending on the required conductivity and transparency and is not specified by a specific value. For example, when the transparent conductive layer 120 is formed of a metal, And when the transparent conductive layer 120 is formed of a metal oxide, it may be formed to have a thickness of 150 nm or less.

The transparent conductive layer 120 may be formed on the graphene layer 110 using a physical or chemical deposition process such as thermal deposition, CVD, sputtering, or the like. The deposition processes listed above are well known, and a detailed description thereof will be omitted.

The transparent conductive layer 120 contributes to achieving high transmittance and low sheet resistance by forming a composite layer with the graphene layer 110. For example, when the transparent conductive layer 120 is formed of an ITO thin film, the resistance decreases as the thickness of ITO increases, but the transmittance decreases as well. The graphene layer 110 is formed on the transparent conductive layer 120, (I.e., the sheet resistance can be lowered through the graphene layer without increasing the thickness of the transparent conductive layer).

On the other hand, when the transparent conductive layer 120 is formed, it may affect the graphene layer 110 under high temperature conditions such as sputtering. Therefore, the step of forming the protective layer 111 on the graphene layer 110 before forming the transparent conductive layer 120 may be performed first.

The protective layer 111 protects the graphene layer 110 when the transparent conductive layer 120 is formed. Examples of the protective layer 111 include polyethyleneterephthalate (PET), poly methyl methacrylate (PMMA), polyvinylidene fluoride (Polystyrene) -co-PMMA-co-PS, PR (Photoresist), ER (Electron Resist), TFSA (CF ₃ SO ₂ ) ₂ NH), water-soluble polyurethane resin, water-soluble epoxy resin, Acrylic adhesives, acrylic adhesives, water-soluble natural polymer resins, water-based adhesives, alcohol peeling tapes, vinyl acetate emulsion adhesives, hot melt adhesives, visible light curing adhesives, infrared curing adhesives, electron beam curing adhesives, polybenizimidazole A bismaleimide (BMI) adhesive, a modified epoxy resin, a glue, a polyvinylalcohol (PVB) tape, a general adhesive tape, and an oxide film such as SiO _x or AlO _x .

The protective layer 111 corresponds to a selectable layer in some cases. Referring to FIG. 2A, the protective layer 111 is absent. In FIG. 2B, when the protective layer 111 is present As shown in Fig. Hereinafter, the case where the protective layer 111 is present will be mainly described (step 2 above).

(3) Step 3 and Step 4

3 and 4, step 3 is a step of forming a cured layer 140 of a first substrate 130, step 4 is a step of bonding a transparent conductive layer 120 and a cured layer 140, (140) is cured by heating or ultraviolet irradiation.

The first substrate 130 is prepared separately from the one described in the first and second steps, and the cured layer 140 is formed on the first substrate 130. The first substrate 130 may have transparency, flexibility, stretchability, or a combination thereof.

The first substrate 130 is made of a polymer containing at least one selected from the group consisting of an olefin group, an ester group, an ether group, an acrylate group, a carbonate group, a cellulose group, a styrene group, an amide group, an imide group and a sulfone group .

Here, the polymer may be at least one selected from the group consisting of polyethylene terephthalate (PET), polyethylene sulfone (PES), polyethylene naphthalate (PEN), polycarbonate (PC), polymethyl methacrylate (PMMA), polyimide (PI), ethylene vinyl acetate EVA, amorphous polyethylene terephthalate (APET), polypropylene terephthalate (PPT), polyethylene terephthalate glycerol (PETG), polycyclohexylenedimethylene terephthalate (PCTG), modified triacetyl cellulose (TAC) (COP), cycloolefin copolymer (COC), dicyclopentadiene polymer (DCPD), cyclopentadiene polymer (CPD), polyarylate (PAR), polyetherimide (PEI), polydimethylsilonane PDMS), a silicone resin, a fluororesin, a modified epoxy resin, and the like, and are not limited to those listed above.

The cured layer 140 is formed on the first substrate 130 in the form of a resin and functions to bond the transparent conductive layer 120 and the first substrate 130 to each other. Examples of the method of forming the cured layer 140 on the first substrate 130 include a doctor blading method, a bar coating method, a spin coating method, a dip coating method, a micro gravure coating method, A solution process such as micro gravure, imprinting, ink jet printing, spray, or the like may be used.

The cured layer 140 can be cured by heat or ultraviolet rays, and for electrons, the cured layer 140 can be a thermosetting layer, and in the latter, the cured layer 140 can be an ultraviolet cured layer.

When the cured layer 140 is a thermosetting layer, it may include a thermoplastic resin and a thermosetting agent. The thermoplastic resin may include at least one member selected from the group consisting of urethane, epoxy, acrylic, and silicone. The thermosetting agent may include at least one selected from the group consisting of isocyanates, amines, and imidazoles. When the cured layer 140 is a thermosetting layer, the transparent conductive layer 120 and the cured layer 140 are formed by laminating the transparent conductive layer 120 to the cured layer 140 and then curing the cured layer 140 by applying heat, Can be bonded. Here, the heat temperature, curing time and the like are not specified.

When the cured layer 120 is an ultraviolet curable layer, it may include an acrylate-based monomer, an acrylate-based oligomer, and a photoinitiator. The acrylate-based monomer and the acrylate-based oligomer may have an aliphatic or aromatic structure containing at least one functional group selected from the group consisting of urethane, epoxy, silicone, ether and polyester. Examples of the acrylate-based monomer include dipentaerythritol pentaacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, polyethylene glycol diacrylate, ), Ethoxyethoxy ethyl acrylate, or benzyl acrylate. Examples of the acrylate oligomer include an aliphatic or aromatic urethane acrylate, an epoxy acrylate, and a polyester acrylate.

When the cured layer 140 is an ultraviolet irradiation layer, it may further include a photoinitiator. Examples of the photoinitiator include 2,4,6-trimethylbenzoyl-diphenylphosphine -diphenyl-diphenyl phosphine, hydroxy cyclohexyl phenyl ketone, hydroxy dimethyl acetophenone, benzyl dimethyl ketal or ethyl-4-dimethylaminobenzoate Ethyl-4-dimethylaminobenzoate).

When the cured layer 140 is an ultraviolet curable layer, the transparent conductive layer 120 is cured to the hardened layer 140 by curing the cured layer 140 by irradiating the transparent conductive layer 120 with ultraviolet (UV) The layer 140 can be bonded. Here, ultraviolet ray intensity and curing time are not specified (steps 3 and 4 above).

(4) Step 5

Referring to FIGS. 5 and 6, step 5 is a step of manufacturing the graphene-based laminate 100 by removing the metal base M. FIG.

The removal of the metal substrate M is carried out by using a roll to roll apparatus including a chamber 2 containing an etching solution 1 for selectively removing the metal substrate M as shown in Fig. Lt; / RTI > That is, only the metal base M can be selectively removed by passing the laminate having the structure shown in Fig. 4 through the roller 3 into the chamber 2 containing the etching solution 1.

The etching solution 1 may be selected corresponding to the kind of the metal substrate M, and examples thereof include hydrogen fluoride (HF), BOE (Buffered Oxide Etch), ferric chloride (FeCl ₃ ) iron (Fe (NO _{3) 3)} has a solution. On the other hand, the structure of the graphene-based laminate 100 from which the metal base M is removed is shown in Fig. The graphene-based laminate 100 has a structure in which the first substrate 130, the cured layer 140, the transparent conductive layer 120, the protective layer 111, and the graphene layer 110 are stacked in this order from the bottom. Here, the protective layer 111 may be omitted (step 5 above).

On the other hand, it is possible to replace the first substrate 130 with the second substrate 150 in the graphen-based laminate 100. Since the substrate replacement process can be performed after the above-described five steps, the process will be referred to as a six-step process. Step 6 may be performed by transferring the transparent conductive layer 120 / protective layer 111 / graphene layer 110 on the first substrate 130 to the second substrate 150. Here, the second substrate 150 may be made of the same or similar material as the first substrate 130. 7, the graphene-based laminate 100 shown in FIG. 6 is transferred onto the second substrate 150. As shown in FIG.

The transfer may be performed using the roll-to-roll process shown in FIG. For example, the first substrate 130 and the cured layer 140 can be removed while the graphene-based laminate 100 shown in FIG. 6 is transferred through the rollers. The first substrate 130 and the cured layer 140 may be removed and the transparent conductive layer 120 and / or the second conductive layer may be removed, The protective layer 111 / graphene layer 110 may be transferred onto the second substrate 150 (step 6 above).

As described above, embodiments of the present invention include a cured layer 140 that is cured by heat or ultraviolet light on a substrate 130 to enable direct transfer of graphene to the substrate, It is possible to produce a graphene-based laminate without degradation and contaminants. In addition, the graphene-based laminate 100 manufactured by the above-described method can form a composite layer of the graphene layer 110 and the transparent conductive layer 120, thereby achieving a high transmittance and a low sheet resistance, while also enabling large-area production.

The present invention can further provide a graphene-based laminate manufactured by the graphene-based laminate manufacturing method according to an embodiment of the present invention.

The graphene-based laminate can be used in the manufacture of electrodes (particularly transparent electrodes) of various electronic and electrical devices such as next generation field effect transistors or diodes that are required to have flexibility and / or elongation potential, or solar cells, touch sensors and related flexible electronic technologies It can be used as a graphene transparent electrode for optoelectronic applications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, many modifications and changes may be made by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

100: graphene-based laminate M: metal substrate
110: Graphene layer 111: Protective layer
120: transparent conductive layer 130: first substrate
140: Cured layer 150: Second substrate

Claims (8)

A first step of growing a graphene layer on the metal substrate to form a graphene layer;
Forming a transparent conductive layer on the graphene layer;
A third step of applying a resin cured by heat or ultraviolet rays onto the first substrate to form a cured layer;
(C) bonding the transparent conductive layer and the cured layer to each other, and then curing the cured layer through heat or ultraviolet irradiation; And
And removing the metal substrate,
The transparent conductive layer may include at least one selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), F-doped tin oxide (FTO), antimony tin oxide (ATO), AZO -IGZO (In2O3: Ga2O3: ZnO) , MgIn 2 O 4, Zn 2 SnO 4, ZnSnO 3, (Ga, In) 2 O 3, Zn 2 In 2 O 5, InSn 3 O 12, In 2 O 3, SnO _{2, Cd 2 SnO 4, CdSnO} 3 and CdIn ₂ O _4, or one or more metal oxides selected from, Cu, Al, Sn, Ni , W, Ti, Cr, Co, Zn, Ta, V, Au, Ag, TiN And Pt, or formed of a Cu nanowire or an Ag nanowire. delete The method according to claim 1,
The cured layer may be a thermosetting layer comprising a thermoplastic resin and a thermosetting agent,
Acrylate monomer, an acrylate oligomer, and an ultraviolet curing agent. The method of claim 3,
Further comprising forming a protective layer on the graphene layer between the first and second steps. The method of claim 1, 3, or 4,
And removing the first substrate using a roll-to-roll process and transferring the graphene layer onto a second substrate. A graphene-based laminate produced by the graphene-based laminate manufacturing method according to any one of claims 1, 3 and 4. Graphene layer; Transparent conductive layer; The transparent conductive layer is formed of a transparent conductive layer such as ITO (indium tin oxide), IZO (indium zinc oxide), FTO (F-doped tin oxide), ATO (antimony tin oxide), AZO ZnO: Al), GZO (ZnO : Ga), a-IGZO (In2O3: Ga2O3: ZnO), MgIn 2 O 4, Zn 2 SnO 4, ZnSnO 3, (Ga, In) 2 O 3, Zn 2 In 2 O _{5, InSn 3 O 12, in} 2 O 3, SnO 2, Cd 2 SnO 4, CdSnO 3 and CdIn ₂ O _4, or one or more metal oxides selected from, Cu, Al, Sn, Ni , W, Ti, Cr, Wherein the hardened layer is at least one metal selected from the group consisting of Co, Zn, Ta, V, Au, Ag, TiN and Pt, or a Cu nanowire or an Ag nanowire and the hardened layer is a thermosetting layer comprising a thermoplastic resin and a thermosetting agent , An acrylate monomer, an acrylate oligomer, and an ultraviolet curing agent. The method of claim 7,
And a protective layer formed between the graphene layer and the transparent conductive layer.

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