KR101880963B1 - Method of manufacturing graphene-coated metal plate - Google Patents

Abstract

One embodiment of the present invention is a method of manufacturing a semiconductor device, comprising: (a) etching a metal plate; (b) placing the etched metal plate in a reactor and exposing it to a mixed gas containing hydrogen and an inert gas; (c) heating the reactor to remove the oxide layer on the metal plate; (d) depositing graphene on the metal plate by injecting carbon-based gas into the reactor; And a flow rate of hydrogen in the mixed gas is 500 to 1,000 sccm.

Description

[0001] METHOD OF MANUFACTURING GRAPHENE-COATED METAL PLATE [0002]

The present invention relates to a method of manufacturing a graphene-coated metal plate, and more particularly, to a method of manufacturing a graphene-coated metal plate by etching a metal plate before graphene deposition, And a manufacturing method thereof.

Graphene can be made from a top-down process that produces graphene from graphite and a bottom-up process that chemically synthesizes graphene from a carbon source.

The mechanical peeling method generally known as a top-down method is a method of mechanically separating graphene from graphite by using the adhesive force of a scotch tape. When the tape is first peeled off, several layers of graphene are separated from the graphite. Therefore, repeated operations are required to obtain a single layer or a smaller number of layers of graphene. The resulting graphene is transferred to a desired target substrate and grafted with a solvent such as acetone to remove the adhesive component. However, there is a possibility that graphene having a high crystallinity can be obtained but the production efficiency is low and contaminated with organic impurities. There is a problem in that it is difficult to control the number of layers and is not sufficient for practical application.

The bottom-up method may be a chemical vapor deposition (CVD) method or an epitaxial growth method. The epitaxial growth method is a method of producing graphene by heat-treating a material such as silicon carbide (SiC) or ruthenium (Ru) containing a carbon source at a high temperature. In the case of silicon carbide, the carbon contained in the silicon carbide crystal is separated from the high temperature to the surface, and graphene grows along the grain surface. In the case of ruthenium (Ru), adsorbed graphene diffuses from the surface and grows into graphene. However, there is a disadvantage in that the electrical characteristics are relatively poor compared with other synthetic methods, and it is difficult to fabricate them in a large area.

Chemical vapor deposition (CVD) is a method of directly growing graphene on a substrate using a carbon source such as methane (CH ₄ ). Large-area single-layer graphenes can be grown on a substrate that is well adsorbed on carbon at a catalytic metal foil such as copper or other high temperatures. The chemical vapor deposition synthesis method is currently the best way to produce high quality graphene in a large area. However, the performance of the graphene synthesized by the CVD synthesis method is affected by the topology of the metal plate, the crystal structure, the solubility of carbon or the temperature of the growth, the cooling rate, the type of catalyst, the pressure, It is influenced by factors. In addition, although the initial electrical characteristics are excellent, there are problems that the characteristics easily change due to external environmental requirements such as temperature, oxygen, and moisture, and studies are required to improve these properties.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a method for manufacturing a metal plate coated with antioxidative graphene having improved durability against external environment requirements such as temperature, .

An aspect of the present invention provides a method of manufacturing a semiconductor device, comprising: (a) etching a metal plate; (b) placing the etched metal plate in a reactor and exposing it to a mixed gas containing hydrogen and an inert gas; (c) heating the reactor to remove the oxide layer on the metal plate; (d) depositing graphene on the metal plate by injecting carbon-based gas into the reactor; And a flow rate of hydrogen in the mixed gas is 500 to 1,000 sccm.

In one embodiment, the metal plate is selected from the group consisting of molybdenum, rhodium, copper, nickel, cobalt, iron, ruthenium, platinum, palladium, gold, silver, aluminum, magnesium, chromium, manganese, silicon, tantalum, titanium, tungsten, vanadium , Iridium, uranium, zirconium, and mixtures of two or more thereof.

In one embodiment, the etching of step (a) may be performed with one selected from the group consisting of nitric acid, sulfuric acid, acetic acid, and phosphoric acid, and mixtures of two or more thereof.

In one embodiment, the etching may be performed for 5 to 60 minutes.

In one embodiment, the flow rate of the inert gas in step (b) may be 200 to 1,000 sccm.

In one embodiment, step (c) may be performed at 700 to 1500 ° C.

In one embodiment, step (c) may be performed for 5 to 30 minutes after the temperature rise of the reactor.

In one embodiment, the carbon-based gas may be selected from the group consisting of hydrocarbon gases, gaseous hydrocarbon compounds, gaseous alcohols having 1 to 6 carbon atoms, carbon monoxide, and mixtures of two or more thereof.

In one embodiment, the hydrocarbon gas may be one selected from the group consisting of methane, ethane, propane, butane, ethylene, propylene, butylene, acetylene, butadiene and mixtures of two or more thereof.

In one embodiment, the gaseous hydrocarbon compound may be selected from the group consisting of pentane, hexane, cyclohexane, benzene, toluene, xylene, and mixtures of two or more thereof.

In one embodiment, the flow rate of the carbon-based gas in the step (d) may be 50 to 200 sccm.

In one embodiment, the deposition of step (d) may be performed for 3 to 30 minutes.

In one embodiment, the Raman spectral intensity ratio (I _D / I _G ) of the graphene may be 0.8 or less.

According to one aspect of the present invention, graphene is deposited on an acid-treated metal plate by a chemical vapor deposition synthesis method, and the flow rate of the hydrogen gas is controlled during the deposition step to form an antioxidant grains having high durability against temperature, oxygen, A fin-coated metal plate can be produced.

It should be understood that the effects of the present invention are not limited to the effects described above, but include all effects that can be deduced from the description of the invention or the composition of the invention set forth in the claims.

1 is a schematic diagram of a reaction step of a chemical vapor deposition (CVD) synthesis method according to an embodiment of the present invention.
2 is a Raman spectrum analysis result according to an embodiment of the present invention and a comparative example.
3 is a result of X-ray photoelectron spectroscopy (XPS) analysis according to an embodiment and a comparative example of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "indirectly connected" . Also, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

An aspect of the present invention provides a method of manufacturing a semiconductor device, comprising: (a) etching a metal plate; (b) placing the etched metal plate in a reactor and exposing it to a mixed gas containing hydrogen and an inert gas; (c) heating the reactor to remove the oxide layer on the metal plate; (d) depositing graphene on the metal plate by injecting carbon-based gas into the reactor; And a flow rate of hydrogen in the mixed gas is 500 to 1,000 sccm.

Wherein the metal plate is selected from the group consisting of molybdenum, rhodium, copper, nickel, cobalt, iron, ruthenium, platinum, palladium, gold, silver, aluminum, magnesium, chromium, manganese, silicon, tantalum, titanium, tungsten, vanadium, iridium, And a mixture of two or more thereof, preferably molybdenum, but is not limited thereto.

The shape of the metal plate may be one selected from the group consisting of a foil, a flat plate, a block or a tube, and preferably, it may be in the form of a foil, but is not limited thereto.

In the step (a), the etching may be performed by nitric acid, but not limited thereto, selected from the group consisting of nitric acid, sulfuric acid, acetic acid, and phosphoric acid and a mixture of two or more thereof. Impurities or metal residues of the metal plate can be removed by performing etching using an acid and the surface of the metal plate can be made optically flat and defect free to increase the reactivity, Defects can be reduced when forming graphene.

The etching may be performed for 5 to 60 minutes, preferably 10 to 30 minutes, but is not limited thereto. If the etching is performed for less than 5 minutes, it is difficult to sufficiently remove impurities or metal residues from the metal plate. If the etching is performed for more than 60 minutes, excessive etching may be performed to lower the surface smoothness of the metal plate.

The flow rate of the inert gas, for example, argon gas in the step (b) may be 200 to 1,000 sccm, and preferably 400 to 600 sccm, but is not limited thereto. It is difficult to produce a high-quality graphene thin film oriented at a crystal face due to the influence of the surface moving speed of atoms on the surface of the metal plate.

The step (c) may be performed at 700 to 1,500 ° C, and preferably at 900 to 1200 ° C, but is not limited thereto. If the temperature is less than 700 ° C, graphene hardly grows sufficiently. If the temperature is more than 1,500 ° C, generated graphene is optionally decomposed to cause unnecessary defects.

The step (c) may be carried out for 5 to 30 minutes after the temperature rise of the reactor, preferably 7 to 15 minutes, but is not limited thereto. If the reaction is carried out for less than 5 minutes, it is difficult to sufficiently remove the oxide layer on the metal plate, and if performed for more than 30 minutes, the energy efficiency may be lowered.

The carbon-based gas may be selected from the group consisting of hydrocarbon gases, gaseous hydrocarbon compounds, gaseous alcohols having 1 to 6 carbon atoms, carbon monoxide, and mixtures of two or more thereof, and preferably hydrocarbon gases. It is not. The carbon-based gas is a carbon source for producing graphene.

The hydrocarbon gas may be any one selected from the group consisting of methane, ethane, propane, butane, ethylene, propylene, butylene, acetylene, butadiene and mixtures of two or more thereof. Preferably, the hydrocarbon gas may be methane , But is not limited thereto.

The gaseous hydrocarbon compound may be selected from the group consisting of pentane, hexane, cyclohexane, benzene, toluene, xylene, and mixtures of two or more thereof, but is not limited thereto.

The flow rate of the carbon-based gas in the step (d) may be 50 to 200 sccm, preferably 80 to 120 sccm, but is not limited thereto. If the flow rate of the carbon-based gas is less than 50 sccm, sufficient carbon is not supplied to form graphene, and it is difficult to generate grains having high crystallinity. When the flow rate is more than 200 sccm, carbon grains are supplied, Can be generated.

The deposition of step (d) may be performed for 3 to 30 minutes, preferably 7 to 15 minutes, but is not limited thereto. When the deposition is carried out for less than 3 minutes, the carbon-based gas is separated into carbon atoms and hydrogen atoms at high temperature, and the separated carbon atoms are not given sufficient time to be deposited on the heated surface of the metal plate, Minute, the application range of graphene can be reduced because the transparency is low due to thickening due to an increase in the number of graphene lamination frequency.

The Raman spectroscopic intensity ratio (I _D / I _G ) of the graphene may be 0.8 or less, preferably 0.45 to 0.6, but is not limited thereto. Raman spectroscopy, which can obtain information on molecular structure by non-destructive analysis using light scattering phenomenon, is very useful for studying the graphene structure of atomic layer thickness.

G-band due to sp ² bond of carbon at 1,585 cm ^-1 wave frequency in Graphene Raman spectrum, 2D-band and wave number due to double scattering at wave number 2,680 cm ^-1 Band (D-band) indicating inelastic scattering and defects / elastic scattering around the substitution point by phonons located at 1,350 cm ^-1 . The D-band is present at the edge of graphene as well as at the defect / substitution point because elastic scattering is involved. Accordingly, the 2D-band is useful for measuring the thickness of the graphene, and the amount of defects can be calculated by calculating the intensity ratio (I _D / I _G ) between the _D -band and the G-band.

Generally, the Raman spectral intensity ratio (I _D / I _G ) of disordered carbon or polycrystalline graphene is about 0.9. The reduction of the Raman spectral intensity ratio (I _D / I _G ) to 0.8 or less, preferably 0.45 to 0.6 means that the intensity of the D-band indicating the defect / substitution point is relatively decreased, It can be seen that the quality is improved.

Hereinafter, embodiments of the present invention will be described in detail.

Grapina  coating Manufacturing method of metal plate

(1) Metal plate etching step

A molybdenum foil (Mo foil, 99.95%) having a size of 1 cm < ² > cm and a thickness of 0.25 mm is immersed in a beaker containing an acid for 20 minutes at room temperature. Subsequently, it is immersed in acetone for 10 minutes and then in ethanol for 10 minutes.

(2) Grain deposition step

Hereinafter, a detailed description will be made with reference to the schematic diagram of the reaction step of the chemical vapor deposition method of FIG.

(Step 1) The metal plate of the above step (1) is placed on a quartz tube and argon / hydrogen gas is injected at atmospheric pressure, and the temperature is raised to 1,000 ° C. At this time, the injection rate of the argon gas is 500 sccm and the injection rate of the hydrogen gas is 200 to 1,000 sccm.

(Second step) The quartz tube is maintained at a growth temperature of 1000 占 폚 for 10 minutes.

(Step 3) The mixture is exposed to a methane / argon / hydrogen mixed gas for 10 minutes. At this time, the gas injection rates of methane and argon are 100 and 500 sccm, respectively, and the hydrogen gas injection rate is the same as the first step.

(Step 4) Cool to room temperature at a rate of 50 ° C / min. When cooling, argon / hydrogen gas is used, and the quartz tube is sealed. The gas injection rate of argon is 500 sccm, and the hydrogen gas injection rate is the same as the first step.

Example  And Comparative Example

Experimental parameters according to Examples and Comparative Examples are shown in Table 1 according to the method of producing the graphene coated metal plate.

division The etching solution (acid) The hydrogen gas injection rate (sccm) Example 1 nitric acid 1,000 Example 2 nitric acid 500 Comparative Example 1 nitric acid 200 Comparative Example 2 Acetic acid 200 Comparative Example 3 Hydrochloric acid 200

Methods for analyzing the characteristics of the graphene-coated metal sheet prepared in the above Examples and Comparative Examples are as follows.

The graphene coated metal sheet prepared through the above Examples and Comparative Examples was analyzed by Raman spectroscopy.

In order to evaluate the protective barrier performance against the oxidation of the graphene coated metal sheet prepared through the above Examples and Comparative Examples, an oxidation operation was performed in an oven at 300 ° C for 2 hours under an atmospheric pressure environment.

Then X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS) analyzes were performed to investigate oxide formation of the graphene coated metal plate produced through Examples and Comparative Examples.

FIG. 2 is a Raman spectrum analysis result of the graphene-coated metal plate produced through the above-described Examples and Comparative Examples. The amount of defects can be calculated by calculating the intensity ratio (I _D / I _G ) of the _D -band and the G-band. For Comparative Example 3, a value of 0.97 representing disordered carbon or quality polycrystalline graphene was measured. When comparing the intensity ratios (I _D / I _G ) of Comparative Examples 1 to 3, when a graphene-coated metal plate was produced under the same conditions except that each of the nitric acid, acetic acid, and hydrochloric acid was used as the etching solution, (I _D / I _G ) at a minimum of 0.89. It can be seen that the nitric acid etching ability is superior to that of nitric acid or acetic acid.

In addition, by removing the impurities and metal residues on the metal surface through the etching step before the graphenes are grown on the surface of the metal plate, high-quality graphene having fewer defects than the graphenes grown on the surface of the metal plate not subjected to the etching step Can be produced.

A comparison of the intensity ratio (I _D / I _G ) of Examples 1 and 2 shows that when a graphene-coated metal plate was produced under the same conditions except that hydrogen gas was injected at 1,000 sccm and 500 sccm, hydrogen gas Example 1 having an injection rate of 1,000 sccm exhibited an intensity ratio (I _D / I _G ) of at least 0.51, indicating that the injection rate of hydrogen gas affects the quality of the graphene produced on the surface of the metal plate.

FIG. 3 is an XPS analysis result of the oxidation of the graphene-coated metal sheet produced through the above-described embodiment and comparative example. After performing the oxidation operation, the oxygen / carbon (O / C) ratio of the graphene coated metal plate can be determined to confirm the performance of the oxidation protection film.

The results of XPS analysis and O / C ratio are shown in the following Table 2, and the results of EDS analysis are shown in Table 3 below.

element Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 C 45.10 43.25 40.40 33.04 27.11 O 17.82 19.77 20.67 30.38 37.71 Mo 37.08 36.98 38.94 36.14 35.18 O / C ratio 0.40 0.46 0.51 0.92 1.39

(Unit: wt%)

division element Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Before oxidation work Mo 39.08 42.11 44.75 47.26 49.03 C 60.92 57.89 55.25 52.74 50.97 O - - - - - After oxidation Mo 34.49 32.96 30.94 29.70 32.24 C 56.89 53.62 54.58 54.61 50.03 O 8.62 13.42 14.49 15.68 17.73

(Unit: wt%)

Generally, when a sample is subjected to a heat treatment for a long time at a high temperature, oxygen can penetrate the grain boundaries of the graphene coating. However, when an oxidation operation is performed at a high temperature of 300 캜, the sample surface may be oxidized. In the case of Comparative Example 3, the O / C ratio of 1.39 and the oxygen content of 17.73 are the highest, and it is difficult to realize the performance as an oxidation preventing film of molybdenum foil.

Both the results of Table 2 and Table 3 show that when the etching solution is used as nitric acid, it has a lower O / C ratio and oxygen content than acetic acid or hydrochloric acid. That is, when nitric acid is used as an etching solution, it is easy to remove impurities and metal residues from the metal plate. As a result of the Raman spectroscopic intensity ratio (I _D / I _G ), it is known that the hydrogen injection rate is closer to 1,000 sccm, the lower the O / C ratio and the oxygen content, and the higher quality graphene is grown on the surface of the metal plate .

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. 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, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims (13)

(a) etching a metal plate with nitric acid;
(b) placing the etched metal plate in a reactor and exposing it to a mixed gas containing hydrogen and an inert gas;
(c) heating the reactor to remove the oxide layer on the metal plate;
(d) depositing graphene on the metal plate by injecting carbon-based gas into the reactor; Lt; / RTI >
Wherein a flow rate of hydrogen in the mixed gas is 500 to 1,000 sccm. The method according to claim 1,
Wherein the metal plate is selected from the group consisting of molybdenum, rhodium, copper, nickel, cobalt, iron, ruthenium, platinum, palladium, gold, silver, aluminum, magnesium, chromium, manganese, silicon, tantalum, titanium, tungsten, vanadium, iridium, And a mixture of at least two of them. delete The method according to claim 1,
Wherein the etching is performed for 5 to 60 minutes. The method according to claim 1,
Wherein the flow rate of the inert gas in the step (b) is 200 to 1,000 sccm. The method according to claim 1,
Wherein the step (c) is performed at 700 to 1500 ° C. The method according to claim 1,
Wherein the step (c) is performed for 5 to 30 minutes after the temperature elevation of the reactor. The method according to claim 1,
Wherein the carbon-based gas is one selected from the group consisting of a hydrocarbon gas, a vapor-phase hydrocarbon compound, a gaseous alcohol having 1 to 6 carbon atoms, carbon monoxide, and a mixture of two or more thereof. 9. The method of claim 8,
Wherein the hydrocarbon gas is one selected from the group consisting of methane, ethane, propane, butane, ethylene, propylene, butylene, acetylene, butadiene and mixtures of two or more thereof. 9. The method of claim 8,
Wherein the gaseous hydrocarbon compound is one selected from the group consisting of pentane, hexane, cyclohexane, benzene, toluene, xylene, and mixtures of two or more thereof. The method according to claim 1,
Wherein the flow rate of the carbon-based gas in step (d) is 50 to 200 sccm. The method according to claim 1,
Wherein the deposition of step (d) is performed for 3 to 30 minutes. The method according to claim 1,
And the Raman spectral intensity ratio (I _D / I _G ) of the graphene is 0.8 or less.

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