KR102497077B1 - Low temperature growth method of crystalline lamellar graphite - Google Patents

Abstract

The present invention relates to a low-temperature growth method of crystalline layered graphite capable of growing crystalline layered graphite to a desired thickness at a low temperature. In the present invention, a metal layer is formed on a substrate with a metal capable of metal induced layer exchange (MILE) with amorphous carbon. An amorphous carbon layer is formed on the metal layer. Crystalline layered graphite is formed on the substrate by metal-induced interlayer exchange between the metal layer and the amorphous carbon layer through low-temperature heat treatment at 720 to 900 K. Then, the step of forming the amorphous carbon layer and the step of exchanging the metal induction layer are repeated a plurality of times to form a layered graphite laminate of the number of layers corresponding to the number of exchanges between the metal induction layers on the substrate.

Description

Low temperature growth method of crystalline lamellar graphite}

The present invention relates to a method for growing crystalline layered graphite, and more particularly, to a method for growing crystalline layered graphite at a low temperature to a desired thickness at a low temperature.

Graphite is the most stable material among allotropes of carbon, has high corrosion resistance, thermal conductivity, and electrical conductivity, and is used in various application fields because it has a layered structure. In particular, the sp2 hybrid orbital bonding structure present inside the graphite crystal is an important feature that provides high mechanical and electrical properties, as confirmed through experiments on graphene and carbon nanotubes.

However, graphite found in nature has a polycrystalline structure and has a high grain boundary density and misorientation angle because graphite crystal grains of a layered structure having crystal grains of several tens of μm or less are combined in different directions. Due to this, it has an sp2 hybrid orbital bonding structure inside the crystal, but the high grain boundary density and misorientation angle of graphite found in nature are the main causes of deterioration of mechanical and electrical properties.

In order to solve this problem, various methods of synthesizing lamellar graphite have been studied. Layered graphite has a structure in which each layer constituting graphite thin film, thick film or bulk graphite is arranged in parallel.

Among these layered graphite, highly oriented pyrolytic graphite (HOPG) having a representative high crystallinity can be synthesized by pyrolyzing a carbon precursor in a high temperature and high pressure environment of 2273 K or higher. However, high-orientation pyrolytic graphite has a disadvantage in that large-area synthesis and mass synthesis are difficult and require a lot of energy to synthesize due to the synthesis conditions of high temperature and high pressure.

Another method for synthesizing layered graphite is to react a gaseous or solid precursor with a metal catalyst having high carbon solubility, such as nickel, iron, or cobalt, at a temperature range of 1000 K to 1500 K, or higher to dissolve carbon or form metal carbide. There is a method of forming layered graphite on the surface of a metal catalyst by precipitating or decomposing it. This method can synthesize layered graphite at a relatively low temperature compared to highly oriented pyrolytic graphite. However, since the amount of carbon in the metal catalyst is limited and only a limited thickness of layered graphite can be grown through a single precipitation process, the thickness of the metal catalyst must be very thick to obtain a certain thickness. For example, in the case of nickel, only layered graphite having a thickness of less than 1% of the thickness of a metal catalyst can be obtained. In addition, when wet etching is used to separate the formed layered graphite from the metal catalyst, a large amount of the metal catalyst is lost by the etching solution.

Registered Patent Publication No. 10-1878733 (Announced on July 16, 2018)

Accordingly, an object of the present invention is to provide a low-temperature growth method of crystalline layered graphite capable of growing crystalline layered graphite to a desired thickness at a low temperature.

Another object of the present invention is to provide a low-temperature growth method of crystalline layered graphite capable of thickly forming large-area layered graphite.

In order to achieve the above object, the present invention comprises forming a metal layer on a substrate with a metal capable of metal induced layer exchange (MILE) and amorphous carbon; forming an amorphous carbon layer on the metal layer; forming crystalline layered graphite on the substrate by metal-induced interlayer exchange between the metal layer and the amorphous carbon layer through low-temperature heat treatment at 720 to 900 K; and repeating the steps of forming the amorphous carbon layer and the step of forming the layered graphite a plurality of times to form a layered graphite laminate having a number of layers corresponding to the number of exchanges between the metal-induced interlayers on the substrate. A low-temperature growth method of graphite is provided.

In the step of forming the layered graphite, the amorphous carbon of the amorphous carbon layer may be diffused into the metal layer and then moved and crystallized between the metal layer and the substrate to form layered graphite.

The material of the substrate may include a metal, a metal oxide, a metal nitride, a non-metal oxide, or a non-metal nitride.

The material of the substrate may include copper, silver, gold, aluminum, tungsten, ruthenium, tantalum, silicon oxide, silicon nitride, aluminum oxide, titanium nitride, tantalum nitride, silicon, or graphite.

In the step of forming the metal layer, the material of the metal layer may include nickel, iron, cobalt, aluminum, gold, silver, copper, platinum, iridium, molybdenum, zirconium, neodymium, or ruthenium.

The forming of the metal layer may include amorphous carbon, amorphous boron, BN, BCN, B ₄ C and Me-X (Me is at least one of Si, Ti, Mo and Zr, X is B, C and N) on the substrate. Forming a seed layer with at least one material among at least one); and forming the metal layer on the seed layer.

In the step of forming the amorphous carbon layer, the amorphous carbon layer may be formed by sputtering, chemical vapor deposition, or a carbonization reaction of carbon hydrogen and a polymer.

In the step of forming the layered graphite, the low-temperature heat treatment time may be 5 seconds to 180 minutes.

In the step of forming the layered graphite, the low-temperature heat treatment may be performed in a vacuum, inert gas, low inert gas, or reducing gas atmosphere.

In the step of forming the layered graphite laminate, next layered graphite may be formed between the previous layered graphite formed by the previous metal-induced intercalation and the metal layer by the subsequent metal-induced intercalation.

The ratio (t _ac /t _m ) of the thickness of the amorphous carbon layer (t _ac ) to the thickness of the metal layer (t _m ) is 0.9 or more.

The metal layer may have a thickness of 1 nm to 10000 nm.

In the step of forming the amorphous carbon layer, the thickness of the amorphous carbon layer may be 1 nm to 10000 nm.

In the step of forming the layered graphite, the layered graphite may have a thickness of 1 nm to 10000 nm.

In the step of forming the layered graphite, the layered graphite may be formed to a thickness corresponding to the thickness of the metal layer.

The present invention also includes forming a metal layer on a substrate with a metal capable of metal induced layer exchange (MILE) with amorphous carbon; forming a first amorphous carbon layer on the metal layer; forming a crystalline first layered graphite on the substrate by metal-induced interlayer exchange between the metal layer and the first amorphous carbon layer through low-temperature heat treatment at 720 to 900 K; forming a second amorphous carbon layer on the metal layer; and forming a crystalline second layered graphite on the first layered graphite by metal-induced interlayer exchange between the metal layer and the second amorphous carbon layer through low-temperature heat treatment at 720 to 900 K. Provides a low-temperature growth method of

The forming of the metal layer may include amorphous carbon, amorphous boron, BN, BCN, B ₄ C and Me-X (Me is at least one of Si, Ti, Mo and Zr, X is B, C and N) on the substrate. Forming a seed layer with at least one material among at least one); and forming the metal layer on the seed layer.

In the step of forming the first layered graphite and the step of forming the second layered graphite, respectively, after the amorphous carbon of the first and second amorphous carbon layers diffuses into the metal layer, the metal layer and the metal layer below the metal layer. It can migrate and crystallize between the layers of the layered graphite.

The low-temperature growth method of crystalline layered graphite, characterized in that the ratio (t _ac /t _m ) of the amorphous carbon layer thickness (t _ac ) and the metal layer thickness (t _m ) is 0.9 or more.

In the step of forming the first layered graphite and the step of forming the second layered graphite, the layered graphite may be formed to a thickness corresponding to the thickness of the metal layer.

According to the present invention, crystalline layered graphite can be grown to a desired thickness on a substrate at a low temperature using metal induced layer exchange (MILE). That is, there was a limit to the thickness at which crystalline layered graphite can be grown in the past, but the present invention repeatedly performs metal-induced interlayer exchange between a metal layer and an amorphous carbon layer, thereby forming a crystalline layer having a thickness proportional to the number of metal-induced interlayer exchanges. Graphite can be grown on a substrate.

As described above, since the present invention can be formed by continuously stacking crystalline layered graphite in the vertical direction on a substrate using metal-induced interlayer exchange, it is possible to overcome the limitation on the thickness of crystalline layered graphite. As a result, the crystalline layered graphite grown according to the present invention can be applied to applications that have previously been difficult to apply due to the thickness limit of crystalline layered graphite, such as large heat sinks, electromagnetic wave shielding coatings, and large battery fields.

Further, according to the present invention, a large area of crystalline layered graphite can be thickly formed to a desired thickness on a substrate by using metal-induced interlayer exchange.

1 is a flow chart according to the low-temperature growth method of crystalline layered graphite according to the present invention.
2 to 7 are views showing each step according to the growth method of FIG. 1 .
8 to 10 are transmission electron microscope (TEM) images showing each step according to the growth method of FIG. 1,
8 is a TEM image showing a state in which a metal layer and a first amorphous carbon layer are stacked on a substrate before metal-induced interlayer exchange;
9 is a TEM image showing a state in which a first layered graphite is grown on a substrate after one metal-induced intercalation;
10 is a TEM image showing a state in which second layered graphite is formed on the first layered graphite after two metal-induced intercalation.

It should be noted that in the following description, only parts necessary for understanding the embodiments of the present invention are described, and descriptions of other parts will be omitted without departing from the gist of the present invention.

The terms or words used in this specification and claims described below should not be construed as being limited to ordinary or dictionary meanings, and the inventors have appropriately used the concept of terms to describe their inventions in the best way. It should be interpreted as a meaning and concept consistent with the technical spirit of the present invention based on the principle that it can be defined in the following way. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only preferred embodiments of the present invention, and do not represent all of the technical spirit of the present invention, so various equivalents that can replace them at the time of the present application. It should be understood that there may be variations and variations.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a flow chart according to the low-temperature growth method of crystalline layered graphite according to the present invention.

Referring to FIG. 1, the low-temperature growth method of layered graphite according to the present invention includes forming a metal layer on a substrate (S10), forming an amorphous carbon layer on the metal layer (S20), and metal-induced interlayer exchange by low-temperature heat treatment ( The step of growing crystalline layered graphite on a substrate by metal induced layer exchange (MILE) (S30), and the step of forming an amorphous carbon layer (S20) and the step of forming layered graphite (S30) are repeated a plurality of times to form metal on the substrate. and forming a layered graphite laminate having a number of layers corresponding to the number of induction interlayer exchanges.

According to the low-temperature growth method of crystalline layered graphite according to the present invention, a layered graphite laminate having a desired thickness can be formed on a substrate through the number of metal-induced interlayer exchanges.

The low-temperature growth method of crystalline layered graphite according to the present invention will be described with reference to FIGS. 1 to 7. Here, FIGS. 2 to 7 are diagrams showing each step according to the growth method of FIG. 1 .

First, in step S10, as shown in FIG. 2, a metal layer 20 is formed on the substrate 10.

Here, as the material of the substrate 10, any material can be used as long as it is difficult for metal or carbon to penetrate in the low-temperature heat treatment process performed in step S30. That is, the material of the substrate 10 may include a metal, a metal oxide, a metal nitride, a non-metal oxide, or a non-metal nitride. For example, as a material of the substrate 10, silicon oxide (SiO ₂ ), silicon nitride (SiN _x ), aluminum oxide (Al ₂ O ₃ ), titanium nitride (TiN), tantalum nitride (TaN), silicon or graphite may be used. , but is not limited to this. The metal is a metal having a melting point of around 1300 K or greater than 1300 K, and may include, for example, copper, silver, gold, aluminum, tungsten, titanium, ruthenium, tantalum, and the like, but is not limited thereto.

For example, the substrate 10 may have a structure in which an etch stopper is formed on a silicon substrate. Here, the etch stop layer is formed of a material having resistance to KOH, and also serves to prevent diffusion of the material of the metal layer into the silicon substrate. The material of the etch stop layer may include at least one of SiN _x , SiO ₂ , SiC, and Mo ₂ C. Here, SiN _x may include Si ₃ N ₄ . The etch stop layer can be formed by the CVD (chemical vapor deposition) process, but it is formed by the ALD (atomic layer deposition) or IBSD (ion beam sputtering deposition) process, so that the thickness, physical properties and chemical composition can be freely adjusted to achieve the best transmittance. It is formed so that defects can be minimized while having The etch stop layer may be formed on the silicon substrate to a thickness of 1 nm to 10 nm.

The metal layer 20 may be formed on the substrate 10 by sputtering or an e-beam evaporation method. The metal layer 20 may be formed on the substrate 10 to a thickness of 1 nm to 10,000 nm.

The metal layer 20 is formed of a metal capable of exchanging between amorphous carbon and metal-induced interlayer. For example, the material of the metal layer 20 may include nickel, iron, cobalt, aluminum, gold, silver, copper, platinum, iridium, molybdenum, zirconium, neodymium, or ruthenium, but is not limited thereto.

A seed layer can be additionally formed between the substrate 10 and the metal layer 20 so that layered graphite can stably grow on the substrate 10 through metal-induced interlayer exchange and secure a stable bonding force on the substrate 10. .

The seed layer is formed of a material that does not react with the material of the metal layer 20, and as a seed for metal-induced interlayer exchange, the heat treatment temperature is lowered and the bonding strength between the layered graphite and the substrate 10 is increased.

Materials for the seed layer include amorphous carbon, amorphous boron, BN, BCN, B ₄ C, and Me-X (Me is at least one of Si, Ti, Mo, and Zr, and X is at least one of B, C, and N). contains at least one The seed layer may be deposited and formed on the substrate 10 to a thickness of 5 nm or less. The seed layer may be formed using various deposition methods such as sputtering, CVD, and ALD.

Next, as shown in FIG. 3, an amorphous carbon layer 31 is formed on the metal layer 20 in step S20. Here, the amorphous carbon layer 31 may be formed by sputtering, chemical vapor deposition, or a carbonization reaction of carbon hydrogen and a polymer. The amorphous carbon layer 31 may be formed on the metal layer 20 to a thickness of 1 nm to 10,000 nm.

Next, as shown in FIGS. 3 and 4 , in step S30 , crystalline layered graphite 30 is grown on the substrate 10 by metal-induced interlayer exchange by low-temperature heat treatment. That is, crystalline layered graphite 30 is formed on the substrate 10 by metal-induced interlayer exchange between the metal layer 20 and the amorphous carbon layer 31 through low-temperature heat treatment at 720 to 900 K. Amorphous carbon of the amorphous carbon layer 31 diffuses into the metal layer 20 and then moves and crystallizes between the metal layer 20 and the substrate 10 to form layered graphite 30 . The layered graphite 30 grown between the substrate 10 and the metal layer 20 may have a thickness of 1 nm to 10,000 nm.

Here, the metal-induced interlayer exchange process is a technique of forming the crystallized layered graphite 30 by simultaneously applying metal-induced crystallization (MIC) and a layer exchange phenomenon. Metal induction crystallization is a technology used in the semiconductor industry to crystallize Si, Ge or its alloy, SiGe, which are Group IV elements, at low temperatures. Metal elements such as nickel, cobalt, iron, aluminum, gold, and palladium This is a method of crystallizing a group 4 element by using a phenomenon in which the crystallization temperature of a group 4 element in contact with a rapidly decreases. The interlayer exchange phenomenon is a phenomenon in which the stacking order of two or more sequentially stacked thin films is reversed under specific reaction conditions.

In the low-temperature growth method according to the present invention, the layered graphite 30 is synthesized at a low temperature around 773 K (500 ℃) by using the feature of lowering the crystallization temperature among the advantages of the metal-induced intercalation process, and at the same time, the interlayer exchange phenomenon is used. It provides a method for synthesizing the layered graphite 30 continuously. In addition, by controlling the conditions and number of times of the metal-induced intercalation process, it is possible to control the thickness of the synthesized layered graphite 30 and the layered graphite laminate (100 in FIG. 7 ).

Here, the low-temperature heat treatment may be performed for 5 seconds to 180 minutes in a vacuum, inert gas, low inert gas, or reducing gas atmosphere. For the low-temperature heat treatment, helium, neon, argon, krypton, xenon, nitrogen, carbon dioxide, methane, hydrogen or ammonia gas may be used, but is not limited thereto. The low-temperature heat treatment time may be appropriately selected in the temperature range of 720 to 900 K depending on the low-temperature heat treatment temperature and the thickness of the layered graphite 30 to be grown. For example, the low-temperature heat treatment temperature may be 720 K to 800 K or 800 K to 900 K. The low temperature heat treatment time may be 5 seconds to 1 minute, 1 minute, 10 minutes, 10 minutes to 60 minutes, 60 minutes to 180 minutes, depending on the low temperature heat treatment temperature.

In order to stably grow the layered graphite 30 by metal-induced interlayer exchange through low-temperature heat treatment, the ratio (t _ac /t _m ) of the thickness of the amorphous carbon layer (t _ac ) and the thickness of the metal layer (t _m ) is preferably 0.9 or more. do. That is, when the thickness ratio (t _ac /t _m ) is less than 0.9, the metal-induced interlayer exchange occurs non-uniformly or the metal-induced interlayer exchange does not occur.

When the thickness ratio (t _ac /t _m ) is greater than or equal to 0.9, the crystalline layered graphite 30 formed on the substrate 10 by metal-induced interlayer exchange by low-temperature heat treatment in step S30 has a thickness corresponding to the thickness of the metal layer 20. is formed

For example, the thickness of the metal layer 20 is 1 nm to 3 nm, 4 nm to 50 nm, 50 nm to 200 nm, 200 nm to 1000 nm, or 1000 nm to 10000 nm, and the thickness of the amorphous carbon layer 31 is 1 nm. nm to 3 nm, 4 nm to 50 nm, 50 nm to 200 nm, 200 nm to 1000 nm, or 1000 nm to 10000 nm, the thickness of the layered graphite 30 is 1 nm to 3 nm, 4 nm to 50 nm nm, 50 nm to 200 nm, 200 nm to 1000 nm, or 1000 nm to 10000 nm.

In step S30, crystalline layered graphite 30 is formed on the substrate 10 by metal-induced interlayer exchange by low-temperature heat treatment, and the metal layer 20 is positioned on the crystalline layered graphite 30.

Meanwhile, the low-temperature heat treatment in step S30 may be performed under pressurized conditions. For example, it means that low-temperature heat treatment is performed under conditions in which pressure is applied to the laminated structure on which the substrate 10, the metal layer 20, and the amorphous carbon layer 31 are formed using a pressure jig or the like. When the low-temperature heat treatment is performed under pressurized conditions, the layered graphite 30 can be grown with a uniform thickness over the entire substrate 10 while metal-induced interlayer exchange is performed faster than when the low-temperature heat treatment is performed without applying pressure. there is.

And as shown in FIGS. 5 to 7 , the layered graphite laminate 100 is formed on the substrate 10 by performing metal-induced interlayer exchange n times (n is a natural number equal to or greater than 2) in step S40 .

That is, in step S40, it is determined whether or not metal induction interlayer exchange has been performed n times. As a result of the determination in step S40, if n times are not performed, the layered graphite laminate having n layers of layered graphite (30, 40, 50) by repeating steps S20 and S30 until the metal-induced interlayer exchange is performed n times. (100) is formed on the substrate (10). That is, by repeating the step of forming the amorphous carbon layers 31 and 41 according to step S20 and the step of forming layered graphite 30, 40, and 50 according to step S30 a plurality of times, the number of exchanges between metal-induced layers on the substrate 10 A layered graphite laminate 100 corresponding to the number of layers is formed. The layered graphite laminate 100 has a structure in which n layered graphite layers 30, 40, and 50 are continuously stacked.

A detailed description of the metal-induced interlayer exchange performed n times is as follows.

First, as shown in FIG. 3, the amorphous carbon layer 31 first formed on the metal layer 20 is referred to as the first amorphous carbon layer 31, and as shown in FIG. 4, metal induction between the first amorphous carbon layer 31 and the metal layer 20 The layered graphite 30 grown by interlayer exchange is referred to as the first layered graphite 30.

Next, after the first metal induction interlayer exchange, the second metal induction interlayer exchange is performed as follows.

First, as shown in FIG. 5 , a second amorphous carbon layer 41 is formed on the metal layer 20 .

Next, as shown in FIGS. 5 and 6, metal-induced interlayer exchange between the metal layer 20 and the second amorphous carbon layer 41 by low-temperature heat treatment results in a crystalline second layer formed on the first layered graphite 30. Grow graphite (40). The second layered graphite 40 and the amorphous carbon of the second amorphous carbon layer 41 diffuse into the metal layer 20 by the same mechanism as the first layered graphite 30, and then the metal layer 20 and the first layered graphite 30 ) is moved and crystallized to form the second layered graphite 40 by growing on the first layered graphite 30.

And, in the same manner, n-th layered graphite is formed between the metal layer 20 and the n-1-th layered graphite by performing n-th metal-induced interlayer exchange after (n-1) times of metal-induced interlayer exchange, so that the first to nth layered graphite is formed. A layered graphite laminate 100 in which layered graphite 30, 40, and 50 are continuously stacked in a vertical direction can be obtained. Here, reference numeral 50 denotes n-th layered graphite.

At this time, since the thickness of the first to n-th layered graphite (30, 40, 50) is determined by the thickness of the metal layer 20, the first to n-th layered graphite (30, 40) through adjusting the thickness of the metal layer 20 ,50) thickness can be adjusted.

Since the thickness of the layered graphite laminate 100 increases as the number of metal induction interlayer exchanges increases, the thickness of the layered graphite laminate 100 can be adjusted by adjusting the number of metal induction interlayer exchanges.

Steps S10, S20 and S30 may be performed in one chamber. Alternatively, at least one of steps S10, S20, and S30 may be performed in a separate chamber.

And as a result of the determination in step S40, if the metal-induced interlayer exchange is performed n times, the low-temperature growth method of crystalline layered graphite (30, 40, 50) is terminated.

As such, according to the present invention, the crystalline layered graphite 30 , 40 , and 50 can be grown on the substrate 10 to a desired thickness at a low temperature by using metal-induced interlayer exchange. That is, there was a limit to the thickness at which crystalline layered graphite can be grown in the past, but the present invention repeatedly performs metal-induced interlayer exchange between the metal layer 20 and the amorphous carbon layers 31 and 41, thereby increasing the number of metal-induced interlayer exchanges. Crystalline layered graphite (30, 40, 50) having a thickness proportional to may be grown by vertically stacking on the substrate (10).

Since the present invention can be formed by continuously stacking crystalline layered graphite (30, 40, 50) in the vertical direction on the substrate 10 using metal-induced interlayer exchange, the crystalline layered graphite (30, 40, 50) It can overcome the limitation on thickness. As a result, crystalline layered graphite (30,40) grown according to the present invention is applied to applications that have previously been difficult to apply due to the thickness limit of crystalline layered graphite (30, 40, 50), such as large heat sinks, electromagnetic wave shielding coatings, and large battery fields. ,50) can be applied.

Further, according to the present invention, large-area crystalline layered graphite 30 , 40 , and 50 may be thickly formed to a desired thickness on the substrate 10 by using metal-induced interlayer exchange.

[Experimental Example]

With respect to the low-temperature growth method of crystalline layered graphite according to the present invention, a layered graphite laminate in which a plurality of layered graphite is laminated was prepared through an experimental example. Step-by-step transmission electron microscope (TEM) images according to the low-temperature growth method of the experimental example are shown in FIGS. 8 to 10. In FIGS. 8 to 10 , first and second layered graphite layers 30 and 40 are sequentially formed on the substrate 10 through two metal-induced interlayer exchanges.

First, as shown in FIGS. 8 and 9 , the first layered graphite 30 is formed by growing the first layered graphite 30 on the substrate 10 through one-time metal-induced interlayer exchange. 8 is a TEM image showing a state in which the metal layer 20 and the first amorphous carbon layer 31 are stacked on the substrate 10 before metal-induced interlayer exchange. 9 is a TEM image showing a state in which the first layered graphite 30 is grown on the substrate 10 after one metal-induced interlayer exchange.

Referring to FIG. 8 , after forming a metal layer 20 to a thickness of 30 nm on a substrate 10 made of silicon oxide, an amorphous carbon layer 31 was formed to a thickness of 40 nm on the metal layer 20 . Here, the substrate 10 has a structure in which a silicon oxide layer is formed on a silicon substrate. A metal layer 20 made of Ni was formed on the silicon oxide layer. A seed layer 60 having a thickness of 1 nm was formed on the silicon oxide layer before forming the metal layer 20 so that layered graphite could be stably grown on the silicon oxide layer and had stable adhesion. As the seed layer 60, amorphous carbon was used.

As shown in FIG. 8, in the state where the first amorphous carbon layer 31 and the metal layer 20 are formed on the substrate 10, as shown in FIG. Through this, the first layered graphite 30 was grown. Heat treatment for one-time metal-induced interlayer exchange was performed in an argon gas atmosphere.

When the thickness ratio (t _ac /t _m ) is 1.33, it can be seen that metal-induced interlayer exchange between the metal layer 20 and the first amorphous carbon layer 31 is smoothly performed. That is, the amorphous carbon of the first amorphous carbon layer 31 diffuses into the metal layer 20 and then moves and crystallizes between the metal layer 20 and the substrate 10 to form the first layered graphite 30 . Accordingly, it can be confirmed that the first layered graphite 30 is grown on the substrate 10 to a uniform thickness, and the metal layer 20 is present on the grown first layered graphite 30 . The amorphous carbon of the seed layer 60 forms the first layered graphite 40 together with the amorphous carbon that has moved from the first amorphous carbon layer 31 through the metal layer 20 by metal-induced interlayer exchange.

In this way, as a method of forming the first layered graphite 30, as shown in FIG. 10, the second layered graphite 40 was formed on the first layered graphite 30. Here, FIG. 10 is a TEM image showing a state in which the second layered graphite 40 is grown on the first layered graphite 30 after two metal-induced intercalation.

A second amorphous carbon layer was formed to the same thickness as the first amorphous carbon layer on the metal layer 20 on which the first layered graphite 30 was formed below.

And, referring to FIG. 10 , the second layered graphite 40 was grown through two-time metal-induced intercalation in which heat treatment was performed at 773 K for 1 hour under the same conditions as the one-time metal-induced intercalation. Heat treatment for two-time metal-induced intercalation was performed in an argon gas atmosphere.

When the thickness ratio (t _ac /t _m ) is 1.33, it can be confirmed that metal-induced interlayer exchange between the metal layer 20 and the second amorphous carbon layer is smoothly performed. That is, the amorphous carbon of the second amorphous carbon layer diffuses into the metal layer 20 and then moves and crystallizes between the metal layer 20 and the first layered graphite 30 to form the second layered graphite 40 . As a result, it can be confirmed that the second layered graphite 40 is grown to a uniform thickness on the first layered graphite 30, and the metal layer 20 is present on the grown second layered graphite 40.

In this way, in the same way as the first and second layered graphite layers 30 and 40 are formed by stacking, the substrate 10 may be formed by stacking the first to nth layered graphite layers.

On the other hand, the embodiments disclosed in this specification and drawings are only presented as specific examples to aid understanding, and are not intended to limit the scope of the present invention. In addition to the embodiments disclosed herein, it is obvious to those skilled in the art that other modifications based on the technical idea of the present invention can be implemented.

10: Substrate
20: metal layer
30: first layered graphite
31: first amorphous carbon layer
40: second layered graphite
41: second amorphous carbon layer
50: n-th layered graphite
60: seed layer
100: layered graphite laminate

Claims (20)

Forming a metal layer on a substrate from a metal capable of metal induced layer exchange (MILE) with amorphous carbon;
forming an amorphous carbon layer on the metal layer;
Forming crystalline layered graphite on the substrate by metal-induced interlayer exchange between the metal layer and the amorphous carbon layer through low-temperature heat treatment at 720 to 900 K; and
Forming a layered graphite laminate of the number of layers corresponding to the number of exchanges between the metal-induced layers on the substrate by repeating the steps of forming the amorphous carbon layer and the step of forming the layered graphite a plurality of times,
Forming the metal layer,
At least one material of amorphous carbon, amorphous boron, BN, BCN, B ₄ C and Me-X (Me is at least one of Si, Ti, Mo and Zr, X is at least one of B, C and N) on the substrate forming a raw seed layer; and
forming the metal layer on the seed layer;
Low-temperature growth method of crystalline layered graphite comprising a. The method of claim 1, wherein in the step of forming the layered graphite,
The low-temperature growth method of crystalline layered graphite, characterized in that the amorphous carbon of the amorphous carbon layer is diffused into the metal layer and then moved and crystallized between the metal layer and the substrate to form layered graphite. According to claim 1,
The material of the substrate is a low-temperature growth method of crystalline layered graphite, characterized in that it comprises a metal, a metal oxide, a metal nitride, a non-metal oxide or a non-metal nitride. According to claim 1,
The material of the substrate is copper, silver, gold, aluminum, tungsten, ruthenium, tantalum, silicon oxide, silicon nitride, aluminum oxide, titanium nitride, tantalum nitride, silicon or graphite Low temperature growth method of crystalline layered graphite, characterized in that . The method of claim 1, wherein in the forming of the metal layer,
The material of the metal layer is a low temperature growth method of crystalline layered graphite, characterized in that it comprises nickel, iron, cobalt, aluminum, gold, silver, copper, platinum, iridium, molybdenum, zirconium, neodymium or ruthenium. delete The method of claim 1, wherein in the forming of the amorphous carbon layer,
The low-temperature growth method of crystalline layered graphite, characterized in that the amorphous carbon layer is formed by sputtering, chemical vapor deposition or carbonization of carbon hydrogen and polymer. The method of claim 1, wherein in the step of forming the layered graphite,
The low-temperature heat treatment time is a low-temperature growth method of crystalline layered graphite, characterized in that 5 seconds to 180 minutes. The method of claim 1, wherein in the step of forming the layered graphite,
The low-temperature heat treatment is a low-temperature growth method of crystalline layered graphite, characterized in that carried out in a vacuum, inert gas, low inert gas or reducing gas atmosphere. The method of claim 1, wherein in the step of forming the layered graphite laminate,
A method for growing crystalline layered graphite at a low temperature, characterized in that the next layered graphite is formed by the subsequent metal-induced intercalation between the previous layered graphite formed by the previous metal-induced intercalation and the metal layer. According to claim 1,
The low-temperature growth method of crystalline layered graphite, characterized in that the ratio (t _ac /t _m ) of the amorphous carbon layer thickness (t _ac ) and the metal layer thickness (t _m ) is 0.9 or more. According to claim 11,
The low-temperature growth method of crystalline layered graphite, characterized in that the thickness of the metal layer is 1 nm to 10000 nm. The method of claim 11, wherein in the forming of the amorphous carbon layer,
The low-temperature growth method of crystalline layered graphite, characterized in that the thickness of the amorphous carbon layer is 1 nm to 10000 nm. The method of claim 11, wherein in the step of forming the layered graphite,
The low-temperature growth method of crystalline layered graphite, characterized in that the thickness of the layered graphite is 1 nm to 10000 nm. The method of claim 11, wherein in the step of forming the layered graphite,
The layered graphite is a low-temperature growth method of crystalline layered graphite, characterized in that formed to a thickness corresponding to the thickness of the metal layer. Forming a metal layer on a substrate of a metal capable of metal induced layer exchange (MILE) with amorphous carbon;
forming a first amorphous carbon layer on the metal layer;
forming a crystalline first layered graphite on the substrate by metal-induced interlayer exchange between the metal layer and the first amorphous carbon layer through low-temperature heat treatment at 720 to 900 K;
forming a second amorphous carbon layer on the metal layer; and
Forming a crystalline second layered graphite on the first layered graphite by metal-induced interlayer exchange between the metal layer and the second amorphous carbon layer through low-temperature heat treatment at 720 to 900 K; Including,
Forming the metal layer,
At least one material of amorphous carbon, amorphous boron, BN, BCN, B ₄ C and Me-X (Me is at least one of Si, Ti, Mo and Zr, X is at least one of B, C and N) on the substrate forming a raw seed layer; and
forming the metal layer on the seed layer;
Low-temperature growth method of crystalline layered graphite comprising a. delete According to claim 16,
The step of forming the first layered graphite and the step of forming the second layered graphite, respectively,
The amorphous carbon of the first and second amorphous carbon layers diffuses into the metal layer, and then moves and crystallizes between the metal layer and the layer below the metal layer to form layered graphite. method. According to claim 16,
The low-temperature growth method of crystalline layered graphite, characterized in that the ratio (t _ac /t _m ) of the amorphous carbon layer thickness (t _ac ) and the metal layer thickness (t _m ) is 0.9 or more. The method of claim 19, wherein in the step of forming the first layered graphite and the step of forming the second layered graphite,
The layered graphite is a low-temperature growth method of crystalline layered graphite, characterized in that formed to a thickness corresponding to the thickness of the metal layer.

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