KR20200014123A - Multi-layered thin film and manufacturing method thereof - Google Patents

Abstract

Disclosed are a multi-layered thin film and a manufacturing method thereof, wherein the multi-layered thin film includes a high-quality graphene in which defects of the graphene are cured. According to the present invention, the multi-layered thin film comprises: a graphene layer; a first barrier layer configured to cure the defects of the graphene layer located on the graphene layer; a conduction layer located on the first barrier layer; and a second barrier layer located on the conduction layer.

Description

Multi-layered thin film and manufacturing method

The present invention relates to a multilayer thin film and a method for manufacturing the same, and more particularly, to a multilayer thin film including a high quality graphene, the defects of the graphene is cured.

Barrier films are used in solar cells, displays, various electronic devices, medicines, food and beverage packaging, etc., and when the electronic devices (electronic devices), medicines, food and beverages are exposed to oxygen and moisture, the product performance Since there is a detrimental effect such as deterioration, it is variously applied for the purpose of preventing them from contacting with oxygen or moisture.

Such barrier films have generally been produced by forming a functional coating layer of a multilayer structure on a plastic substrate. For example, a barrier film having a multilayer structure composed of a combination of an inorganic barrier layer for blocking gas such as oxygen and water vapor, and an organic barrier layer for imparting flatness and reducing defects on the surface of the plastic substrate. However, since the conventional barrier film having such a structure still does not satisfy the high performance barrier properties, efforts to develop a barrier film conforming to the high performance barrier properties continue.

Meanwhile, graphene, a carbon allotrope, is a new material consisting of a monoatomic layer having a hexagonal honeycomb shape. Graphene is known to have a high chemical and thermal stability. Therefore, research on barrier materials, heat / chemical materials, and the like has been progressed in various ways by applying graphene.

Currently, a variety of methods for preparing graphene are known. Among them, graphene prepared by chemical vapor deposition (CVD) is known to be the most excellent in characteristics and most suitable for mass production. However, as the graphene pieces grown at any point on the growth substrate are combined to form a graphene layer, the graphene growth point is arbitrarily selected, so that the size of each grown graphene region, that is, the domain of graphene, is increased. Is not constant, and defects occur in portions overlapping with other graphene domains, thereby causing problems in terms of reliability when graphene is applied to barrier films or other fields.

The present invention has been made to solve the above problems, an object of the present invention, to provide a multilayer thin film comprising a high-quality graphene, the defects of the graphene is cured, and a method of manufacturing the same.

Graphene layer according to an embodiment of the present invention for achieving the above object; A first barrier layer that heals a defect of the graphene layer positioned on the graphene layer; A conductive layer located on the first barrier layer; And a second barrier layer positioned on the conductive layer.

The first barrier layer may be formed by arranging atoms in a defect region existing on the graphene layer.

The first barrier layer and the second barrier layer may be layers of atoms of metal or metal oxides.

The conductive layer may comprise a metal.

The thickness of the graphene layer may be 0.1 nm to 1.0 nm, the thickness of the first barrier layer may be 1.0 nm to 5.0 nm, the thickness of the conductive layer may be 10 to 50 nm, and the thickness of the second barrier layer may be 30 to 50 nm.

According to another aspect of the invention, the step of forming a graphene layer by a chemical vapor deposition process on a metal substrate; Forming a first barrier layer on the graphene layer by an atomic layer deposition process; Forming a conductive layer on the first barrier layer by a sputtering process; And forming a second barrier layer on the conductive layer.

Metal substrates include Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, brass, bronze, cupronickel, stainless steel and One or more metals or alloys thereof selected from the group consisting of Ge.

Forming the first barrier layer may be an ozone-based atomic layer deposition process.

The graphene layer may include at least one of single layer graphene and multilayer graphene.

Forming the first barrier layer may be performed at 70 to 100 ° C.

According to another aspect of the invention, the step of forming the irregularities on the metal substrate; Forming a graphene layer on a metal substrate by a chemical vapor deposition process; Forming a first barrier layer on the graphene layer by an atomic layer deposition process; Forming a conductive layer on the first barrier layer by a sputtering process; And forming a second barrier layer on the conductive layer.

According to another aspect of the present invention, there is provided a multilayer thin film produced by the method of manufacturing a multilayer thin film, wherein the irregularities of the metal substrate are transferred to the surface of the graphene layer.

As described above, according to the embodiments of the present invention, by forming a barrier layer on the graphene layer, a defect of the graphene layer may be cured, thereby manufacturing a multilayer thin film having excellent barrier performance and mechanical flexibility.

In addition, it is possible to obtain a multilayer thin film having irregularities formed on the graphene layer, and when used in an optical device, the multilayer thin film may exhibit excellent conductivity and flexibility while also inducing light scattering on the surface to increase optical efficiency of the device. Can be.

1 is a cross-sectional view of a multilayer thin film according to an embodiment of the present invention, Figure 2 is a schematic diagram showing that the first barrier layer heals a defect formed on the graphene layer.
3 is an optical surface image of a multilayer thin film prepared by an ozone-based atomic layer deposition process, FIG. 4 is an optical surface image of a multilayer thin film prepared by an oxygen-based atomic layer deposition process, and FIG. 5 is H ₂ O. An optical surface image of a multilayer thin film produced by a base atomic layer deposition process.
6 are Raman spectrum measurement results and planar images after the deposition process is performed by an ozone-based atomic layer deposition process, an oxygen-based atomic layer deposition process, and a H ₂ O-based atomic layer deposition process, respectively.
7 to 10 are views provided for the description of the method for manufacturing a multilayer thin film according to another embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. In the accompanying drawings, there may be a component having a specific irregularity or a predetermined thickness, but this is for convenience of description or distinction. It is not limited only.

1 is a cross-sectional view of a multilayer thin film according to an embodiment of the present invention, Figure 2 is a schematic diagram showing that the first barrier layer heals a defect formed on the graphene layer. The multilayer thin film 100 according to the present embodiment includes a graphene layer 120; A first barrier layer 130 to cure a defect of the graphene layer 120 positioned on the graphene layer 120; A conductive layer 140 positioned on the first barrier layer 130; And a second barrier layer 150 positioned on the conductive layer 140.

The multilayer thin film 100 of the present invention includes a graphene layer 120. Graphene is a plurality of carbon atoms are covalently linked to each other to form a polycyclic aromatic molecule to form a layer or sheet form. Graphene has very high chemical and thermal stability, and its layered structure has high conductivity and heat dissipation. Therefore, the multilayer thin film 100 of the present invention can be produced in a very thin film including graphene showing excellent barrier properties.

Graphene can be manufactured by various methods. Chemical vapor deposition (CVD) is used to provide excellent graphene properties and mass production. Chemical Vapor Deposition (RTCVD), Inductively Coupled Plasma Chemical Vapor Deposition (ICP-CVD), Low Pressure Chemical Vapor Deposition (LPCVD), Atmospheric Chemical Vapor Deposition (APCVD), Metal Organic Chemical Vapor Deposition (MOCVD) or Chemical Subdivided by vapor deposition (PECVD) or the like.

The covalently linked carbon atoms constituting the graphene grown at any point on the growth substrate form a 6-membered ring as a basic repeating unit, but may further include a 5- or 7-membered ring. In particular, when the growth direction of the graphene in the domain boundary of the graphene is different, each domain collides to form a 5-membered ring or a 7-membered ring, and such irregular crystal arrangements cause the degradation of graphene.

The domain of graphene refers to a region in which crystal grows as a result of graphene growth from any point and thus causes horizontal expansion. That is, the graphene within the boundary formed at the point where the region of the graphene formed from one point and the region of the graphene formed at another point meets is called a domain. At the interface of the graphene domain, irregular contact is generated during contact between the domains due to the difference in the growth direction of different domains, and such irregularity may act as a defect of the graphene.

Graphene is a single layer of covalently bonded carbon atoms (usually sp ² bonds). Graphene may have a variety of structures, such a structure may vary depending on the content of 5-membered and / or 7-membered rings that can be included in the graphene. In addition, the graphene may form a multilayer graphene having a plurality of layers by stacking a plurality of single layer graphene with each other.

In order for the excellent properties of graphene to be expressed in the barrier film, it is necessary to minimize the above-described defects of graphene. In the present invention, the first barrier layer 130 is formed on the graphene layer 120 to heal the defects of the graphene layer 120. Referring to FIG. 2, a part of the multilayer thin film 100 is shown, and a defect is formed in the center portion of the graphene layer 120, and when only the graphene layer 120 is used as a barrier film, Moisture or impurities can be penetrated. Therefore, the barrier performance of the barrier film is changed according to the defect degree of the graphene layer 120.

A first barrier layer 130 is formed on the graphene layer 120, and the first barrier layer 130 may be formed by arranging atoms in a defect region existing on the graphene layer 120. When atoms are arranged on the graphene layer 120, the atoms are first stacked in the defect region of the graphene layer 120. Therefore, the graphene layer 120 is filled with the defect region by the first barrier layer 130, thereby increasing the barrier performance.

Since the first barrier layer 130 is to be deposited in atomic units, the first barrier layer 130 may be formed by an atomic layer deposition process, unlike the graphene layer 120 formed by a chemical vapor deposition process. Atomic layer deposition (ALD) is an atomic unit deposition process in which a precursor gas of atoms to be deposited is injected and a reaction gas is injected together to form a thin film by laminating atoms in a deposition substrate as a layer. to be. In the atomic layer deposition process, one atomic layer thin film layer 130 is formed on the graphene layer 120 through a plurality of (about 5) atomic layer deposition processes. Therefore, when the thin film layer is formed on the graphene layer 120 according to the atomic layer deposition process, defects formed in the graphene layer 120 may be cured. Since the first barrier layer 130 is formed on the graphene layer 120 to fill the voids or channels generated on the surface of the graphene layer 120, it is impossible to penetrate moisture from the outside, thereby exhibiting an optimal effect as a barrier film. Can be.

The first barrier layer 130 may be a layer of atoms of a metal or a metal oxide. Metal oxides that may be used in the first barrier layer 130 include silicon oxide, silicon nitride, silicon nitride oxide, aluminum oxide, aluminum nitride, or aluminum nitride oxide.

The conductive layer 140 is positioned on the first barrier layer 130. Conductive layer 140 comprises a metal. When the conductive layer 140 including the metal is included in the multilayer thin film 100, the flexibility of the multilayer thin film 100 may be improved and the conductive performance may be improved, and the conductive layer 140 may act as a buffer layer in a later process. When applying a high energy process, such as a plasma process or an ion beam process can be performed without damaging the graphene layer 120.

The metal that may be used for the conductive layer 140 is a metal having high electrical conductivity, and may be, for example, any one of Ag, Cu, Al, Ir, In, Ni, Mg, Pt, and Pd.

The conductive layer 140 may be any process as long as the metal thin film forming process. For example, the conductive layer 140 may be formed by a sputtering process.

The second barrier layer 150 is formed on the conductive layer 140. The second barrier layer 150 is to improve the barrier performance of the multilayer thin film 100, and may be a layer of atoms of a metal or a metal oxide like the first barrier layer 130. Metal oxides that may be used in the second barrier layer 150 include silicon oxide, silicon nitride, silicon nitride oxide, aluminum oxide, aluminum nitride, or aluminum nitride oxide.

In the multilayer thin film 100 according to the present invention, the thickness of the graphene layer 120 is 0.1 nm to 1.0 nm, the thickness of the first barrier layer 130 is 1.0 nm to 5.0 nm, and the conductive layer 140 The thickness may be 10 to 50 nm, and the thickness of the second barrier layer 150 may be 30 to 50 nm.

Multi-layer thin film 100 according to the present invention comprises the steps of forming a graphene layer 120 by a chemical vapor deposition process on the metal substrate 110; Forming a first barrier layer 130 on the graphene layer 120 by an atomic layer deposition process; Forming a conductive layer 140 on the first barrier layer 130 by a sputtering process; And forming a second barrier layer 150 on the conductive layer 140.

Metal substrate 110 is Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, brass, bronze, cupronickel, One or more metals or alloys thereof selected from the group consisting of stainless steel and Ge. When the metal substrate 110 is used, the graphene layer 120 is excellent in characteristics, but the characteristics of the metal may affect the metal substrate 110 in a later process.

Therefore, it is preferable not to adversely affect the metal substrate 110 in the process of forming the first barrier layer 130, the conductive layer 140, and the second barrier layer 150. An atomic layer deposition process may be used to form a thin film layer of the first barrier layer 130 and the second barrier layer 150. The atomic layer deposition process may be an ozone-based atomic layer deposition process, an oxygen-based atomic layer deposition process, or H. ₂ can be subdivided into O-based atomic layer deposition processes.

3 is an optical surface image of a multilayer thin film prepared by an ozone-based atomic layer deposition process, FIG. 4 is an optical surface image of a multilayer thin film prepared by an oxygen-based atomic layer deposition process, and FIG. 5 is H ₂ O. An optical surface image of a multilayer thin film produced by a base atomic layer deposition process.

3A to 3C are optical images after 5, 20 and 100 depositions of an Al ₂ O ₃ layer on the graphene layer by an ozone-based atomic layer deposition process, respectively. In the image of the ozone-based atomic layer deposition process performed five times, defects of the graphene layer are confirmed, but the defects of graphene are started to heal in FIG. 3b, which is performed 20 times, and the defects of graphene in FIG. You can see that this is almost healing.

4A to 4C are optical images after 5, 20 and 100 depositions of an Al ₂ O ₃ layer on the graphene layer by an oxygen-based atomic layer deposition process, respectively. In FIG. 4, the oxygen-based atomic layer deposition process was performed, and it was confirmed that the defects of graphene were healed from FIG. 4C after 100 depositions as in the ozone-based atomic layer deposition process.

5A to 5C are optical images after 5, 20 and 100 depositions of an Al ₂ O ₃ layer on a graphene layer by H ₂ O based atomic layer deposition processes, respectively. In FIG. 5, the H ₂ O-based atomic layer deposition process was performed. Unlike the ozone-based atomic layer deposition process or the oxygen-based atomic layer deposition process, even after 100 depositions, a region in which graphene defects are not healed remains as shown in FIG. 5C. Could confirm. In the case of Yes that the pin defect not heal region of Figure 5c, a multi-layer graphene as a multi-layer graphene zone, the wettability of the H ₂ O is a problem because they are not carried out H ₂ O based on the atomic layer deposition process.

Therefore, when the graphene layer includes multilayer graphene, it is preferable to form the first barrier layer by using an ozone-based atomic layer deposition process or an oxygen-based atomic layer deposition process.

6 are Raman spectrum measurement results and planar images after the deposition process is performed by an ozone-based atomic layer deposition process, an oxygen-based atomic layer deposition process, and a H ₂ O-based atomic layer deposition process, respectively. The ozone-based atomic layer deposition process is performed at about 80 ° C, the oxygen-based atomic layer deposition process is performed at about 100 ° C, and the H ₂ O-based atomic layer deposition process is performed at about 120 ° C.

The ozone-based atomic layer deposition process showed no effect on the metal substrate. However, in the image in which the oxygen-based atomic layer deposition process is performed, there is a problem in that defects are additionally formed on the graphene surface and the boundary due to the plasma radical by-products during the oxidation of the metal substrate and the formation of the oxygen plasma. In addition, in the case of FIG. 6C in which the H ₂ O-based atomic layer deposition process is performed, substrate damage may occur due to heating at about 120 ° C. FIG.

Accordingly, it is preferable to form the first barrier layer by an ozone-based atomic layer deposition process in which the first barrier layer can be formed on the multilayer graphene without affecting the metal substrate and the graphene layer. In addition, by the ozone (O ₃ ) used in the ozone-based atomic layer deposition process, a functional group containing oxygen may be added to the surface of the first barrier layer 130 to activate the surface of the first barrier layer 130. Accordingly, there is an advantage that the chemical vapor deposition process can be effectively performed when the conductive layer 140 is formed.

In the method of manufacturing a multilayer thin film according to the present invention, the first barrier layer forming step may be performed at 70 to 100 ° C. (ozone based atomic layer deposition process) to minimize the influence on the metal substrate.

7 to 10 are views provided for the description of the method for manufacturing a multilayer thin film according to another embodiment of the present invention. According to the present embodiment, the step of forming the unevenness 111 on the metal substrate 110; Forming a graphene layer 120 on the metal substrate 110 by a chemical vapor deposition process; Forming a first barrier layer 130 on the graphene layer 120 by an atomic layer deposition process; Forming a conductive layer 140 on the first barrier layer 130 by a sputtering process; And forming a second barrier layer 150 on the conductive layer 140. According to the method of manufacturing the multilayer thin film according to the present embodiment, the unevenness 111 of the metal substrate 110 is transferred to the surface of the graphene layer 120, and the unevenness is formed on the surface of the graphene layer of the finally formed multilayer thin film 100. Will be formed.

The unevenness 111 is formed on the surface of the metal substrate 110 (FIG. 7). The shape of the unevenness 111 may correspond to the shape of the unevenness to be formed in the graphene layer 120. Since the thickness of the graphene layer 120 is thin, if the height difference between the peaks and valleys of the unevenness 111 is too large, it may be difficult to form the graphene layer 120 with high quality uniformly on the surface of the metal substrate 110. In addition, a defect may occur in the graphene layer 120 formed on the valley of the unevenness 111 due to the surface characteristics.

Accordingly, after the graphene layer 120 is formed on the metal substrate 110 by the chemical vapor deposition process (FIG. 8), the first barrier layer 130 is formed on the graphene layer 120 by the atomic layer deposition process. (FIG. 9). The atomic layer deposition process is an atomic unit deposition process, in which a layer of atoms is deposited on a deposition target to form a thin film, thereby preventing defects in the graphene layer 120 on the metal substrate 110 on which the unevenness 111 is formed. Can be.

The conductive layer 140 is formed on the first barrier layer 130 by a sputtering process. The conductive layer 140 is a layer functioning as a barrier layer of the graphene layer 120 while improving the conductivity of the graphene layer 120 to improve the conductivity of the multilayer thin film 100. The second barrier layer 150 is formed on the conductive layer 140 to finally form all of the barrier layers of the graphene layer 120.

Referring to FIG. 9, the graphene layer 120, which is thinner than other layers due to the unevenness 111 of the metal substrate 110, shows the shape of the unevenness 111, but the first barrier layer 130 is conductive. As the layer 140 and the second barrier layer 150 are stacked, the acid and valley regions of the unevenness 111 are smoothed. Therefore, after the multilayer thin film 100 is formed and the metal substrate 110 is removed (FIG. 10), the graphene layer 120 having the unevenness is formed on the surface of the multilayer thin film 100, and the surface smoothed below. The second barrier layer 150 having the position is positioned.

In the multilayer thin film 100 manufactured according to the present embodiment, a pattern or irregularities of a desired shape may be formed on the surface of the graphene layer 120, and various functions may be provided. For example, when the multilayer thin film 100 is used as a transparent electrode of a solar cell, the light efficiency of the solar cell is increased since the light scattering effect is obtained due to surface irregularities. In addition, the pattern or irregularities are formed on the surface of the multilayer thin film 100, the surface activity is increased, and the effective specific surface area is increased it can be applied to various kinds of devices.

As described above, embodiments of the present invention have been described, but those skilled in the art may add, change, delete, or add elements within the scope not departing from the spirit of the present invention described in the claims. The present invention may be modified and changed in various ways, etc., which will also be included within the scope of the present invention.

100: multilayer thin film
110: metal substrate
120: graphene layer
130: first barrier layer
140: conductive layer
150: second barrier layer

Claims (12)

Graphene layer;
A first barrier layer that heals a defect of the graphene layer positioned on the graphene layer;
A conductive layer located on the first barrier layer; And
And a second barrier layer on the conductive layer. The method according to claim 1,
The first barrier layer is
Multilayer thin film, characterized in that the atoms are arranged in a defect region existing on the graphene layer. The method according to claim 1,
The first barrier layer and the second barrier layer is a multilayer thin film, characterized in that the layer of atoms of the metal or metal oxide. The method according to claim 1,
Multi-layer thin film, characterized in that the conductive layer comprises a metal. The method according to claim 1,
The thickness of the graphene layer is 0.1nm to 1.0nm,
The thickness of the first barrier layer is 1.0 nm to 5.0 nm,
The thickness of the conductive layer is 10-50 nm,
The thickness of the second barrier layer is a multilayer thin film, characterized in that 30 to 50nm. Forming a graphene layer on a metal substrate by a chemical vapor deposition process;
Forming a first barrier layer on the graphene layer by an atomic layer deposition process;
Forming a conductive layer on the first barrier layer by a sputtering process; And
Forming a second barrier layer on the conductive layer; The method according to claim 6,
Metal substrates include Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, brass, bronze, cupronickel, stainless steel and Method for producing a multilayer thin film, characterized in that it comprises one or more metals or alloys thereof selected from the group consisting of Ge. The method according to claim 6,
Forming the first barrier layer is a multilayer thin film manufacturing method, characterized in that the ozone-based atomic layer deposition process. The method according to claim 8,
Graphene layer is a multilayer thin film manufacturing method characterized in that it comprises a single layer graphene and multilayer graphene. The method according to claim 6,
Forming the first barrier layer is a multilayer thin film manufacturing method, characterized in that carried out at 70 to 100 ℃. Forming irregularities on the metal substrate;
Forming a graphene layer on a metal substrate by a chemical vapor deposition process;
Forming a first barrier layer on the graphene layer by an atomic layer deposition process;
Forming a conductive layer on the first barrier layer by a sputtering process; And
Forming a second barrier layer on the conductive layer; As a multilayer thin film manufactured by the method of manufacturing a multilayer thin film of claim 11,
Multilayer thin film, characterized in that the irregularities of the metal substrate is transferred to the surface of the graphene layer.

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