KR101723521B1 - Apparatus for growing a graphene - Google Patents

Abstract

An embodiment includes a chamber; A dome disposed within the chamber and having a susceptor disposed therein and forming a closed space; A raw material supply unit disposed inside the dome and supplying the raw material gas toward the susceptor; A heater for heating the dome; And an air supply unit for supplying air into the chamber, wherein an air inlet is formed in a lower region of the chamber, and an air outlet is formed in an upper region of the chamber.

Description

{APPARATUS FOR GROWING A GRAPHENE}

An embodiment relates to a graphen growth apparatus, and more particularly, to an apparatus for growing graphene by a CVD (chemical vapor deposition) method.

Low-dimensional nanomaterials composed of carbon atoms include fullerene, carbon nanotube, graphene, and graphite. That is, when the carbon atoms form a hexagonal shape and become a ball, fullerene, which is a 0-dimensional structure, carbon nanotubes when dried in a 1-dimensional manner, graphene when made up of one atom in two-dimensional form, can do.

Graphene is not only very stable and excellent in electrical / mechanical / chemical properties, it is also a good conductive material that can move electrons 100 times faster than silicon and can flow about 100 times more current than copper. It has been proved through experiments that a method of separating the particles has been found.

Graphene has the advantage that it is very easy to fabricate 1D or 2D nanopatterns because it is composed of carbon, which is a relatively light element, and it can control the semiconductor-conductor properties as well as the variety of chemical bonds of carbon. It is possible to manufacture a wide variety of functional devices such as sensors and memories.

Despite the excellent electrical / mechanical / chemical properties of graphene, mass-synthesis methods have not been developed in the past, so research on practical applications has been limited.

In the conventional mass synthesis method, graphite was mechanically pulverized and dispersed in a solution, followed by self-assembly to form a thin film. The advantage of being able to synthesize at a relatively low cost, however, is that the electrical and mechanical properties of the graphene pieces are not as expected due to the overlapping structure of the graphene pieces.

Graphene can be used as a substitute for indium tin oxide (ITO), a typical transparent electrode, especially in the display field.

ITO is widely applied to displays, touch screens, solar cells, etc. Recently, due to the depletion of indium, the unit price has risen and urgent development of alternative materials has been required. In addition, due to the property of ITO which is easy to break, application to next generation electronic products that can be folded, bent or stretched has been greatly restricted.

Graphene has the advantage of being able to synthesize and pattern in a relatively simple manner while having excellent stretchability, flexibility and transparency.

1 is a view showing a conventional graphene growth apparatus.

The graphene growth apparatus shown in FIG. 1 is an apparatus for growing graphene by a CVD (chemical vapor deposition) method.

The graphene growth apparatus 100 may have a dome 120 forming a closed space in the chamber 110 and a susceptor 130 for growing graphene may be disposed inside the dome 120 . A heater 140 is disposed under the dome 130 to heat the inside of the chamber 110. An air supply unit 150 is disposed outside the chamber 110 to supply air into the chamber 110 The temperature inside the chamber 110 can be adjusted.

However, the conventional graphene growth apparatus 100 has the following problems.

During the growth of the graphene, the inside of the chamber 110 is heated to 800 ° C or more. Since air can be supplied only to the lower region of the chamber 110 in the air supply unit 150, cooling of the lower region of the dome 120 is difficult.

To solve this problem, there is an attempt to use a separate cooling module, but in the case of rapid cooling using a separate cooling module, the thickness of the grown graphene may become uneven or crack may occur.

The embodiment is intended to provide a graphen growth apparatus that uniformly cools a region inside a chamber in a graphene growth apparatus and is excellent in the quality of the grown graphene.

An embodiment includes a chamber; A dome disposed within the chamber and having a susceptor disposed therein and forming a closed space; A raw material supply unit disposed inside the dome and supplying the raw material gas toward the susceptor; A heater for heating the dome; And an air supply unit for supplying air into the chamber, wherein an air inlet is formed in a lower region of the chamber, and an air outlet is formed in an upper region of the chamber.

The air inlet and the air outlet may be disposed facing each other with the dome therebetween.

The graphene growth apparatus may further include an air ejection port connected to the air supply unit and supplying air into the chamber, and the air ejection port may include a first air ejection opening and a second air ejection opening having different air ejection angles have.

The graphene growth apparatus may further include valves disposed respectively in the first air ejection port and the second air ejection port.

The graphene growth apparatus may further include a power control unit for adjusting a supply amount of air supplied from the air supply unit to the chamber.

The graphene growth apparatus may further include cooling water for cooling air supplied from the air supply unit to the chamber.

The graphene growth apparatus may further include a cooling pipe disposed inside the dome.

The graphene growth apparatus may further include a cooling tube disposed on an outer surface of the dome.

Air or cooling water can flow into the inside of the cooling pipe.

The dome can be made of quartz.

The cooling pipe may be made of a material of a sustain type, a ceramic type or a graphite type.

In the graphene growth apparatus according to the embodiment, when the graphene is grown by the CVD process, air is supplied through the inlet at the lower left side of the chamber in the process of cooling the chamber and the dome and is discharged through the outlet at the upper right side, Cooling can be achieved in the region.

Therefore, the cooling speed of the inside of the chamber can be maintained at 5 DEG C / sec or more without using a separate cooling module, so that the thickness of the graphene grown on the susceptor can be uniform and the occurrence of cracks can be prevented .

FIG. 1 is a view showing a conventional graphene growth apparatus,
2 is a view showing a first embodiment of a graphene growth apparatus,
FIG. 3 is a graph showing changes in volume and temperature of air supplied to the graphene growth apparatus,
4 is a view showing an air supply unit of the second embodiment of the graphene growth apparatus,
5 is a view showing an air supply unit of the third embodiment of the graphene growth apparatus,
6 is a view showing the air supply unit of the fourth embodiment of the graphene growth apparatus,
7 is a view showing an air supply unit of the fifth embodiment of the graphene growth apparatus,
8 is a view showing the air supply unit of the sixth embodiment of the graphene growth apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The same components as those in the prior art are denoted by the same names and the same reference numerals for convenience of description, and a detailed description thereof will be omitted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The same components as those in the prior art are denoted by the same names and the same reference numerals for convenience of description, and a detailed description thereof will be omitted.

The graphene growth apparatus according to the embodiment can grow graphene by a CVD (Chemical Vapor Deposition) method. In particular, air is supplied from the lower portion of the chamber and air is exhausted from the lower portion to smoothly discharge heat from the dome, And the cooling speed of the dome can be increased.

2 is a view showing a first embodiment of a graphene growth apparatus.

The graphene growth apparatus 200 according to the embodiment is an apparatus for growing graphene by a CVD (chemical vapor deposition) method.

The graphene growth apparatus 200 has a closed space in the chamber 210 and a dome made of quartz is formed in the chamber 210. The susceptor 230 is disposed inside the dome, A thin film of graphene (g) may be grown.

The details will be described below.

The dome includes an upper dome 220a and a lower dome 220b. Inside the chamber 210, lower heaters 240a and 240b are provided.

The chamber 210 is formed in the shape of a cylinder having an open top and a bottom, that is, a circular band. The chamber body 215 serves as a sidewall of the reaction space in the chamber 210. However, the chamber body 215 may be formed as a polygonal cylinder.

The upper dome 220a may be the upper cover of the chamber body 215 and the upper dome 220a may be attached to the upper surface of the chamber body 215 such that the lower region of the dome, Thereby sealing the upper region. At this time, the upper dome 220a may be detachably attached to the chamber body 215.

The lower dome 220b may be a lower cover of the chamber body 215. [ The lower dome 220b is attached to the lower surface of the chamber body 215 to seal the lower region of the reaction space.

A drive shaft 235 extending to the outside of the reaction space and a drive unit 238 for moving the drive shaft 235 up and down may be disposed below the susceptor 230. [

The susceptor 230 is formed in a plate shape and is made of a material having excellent thermal conductivity. Also, the susceptor 230 is provided with at least one substrate seating area.

On the susceptor 230, a raw material supply portion is provided, which includes a head and a nozzle, and the raw material gas or the like can be supplied from the side of the susceptor via the nozzle.

An air blower 250 is disposed outside the chamber 210 to supply air into the chamber 210 and adjust the temperature inside the chamber 210.

The lower heaters 240a and 240b may be provided outside the upper dome 220a and the lower dome 220b, respectively, to supply radiant heat to the reaction space.

One lower heater 240a may be disposed below the other lower heater 240b. The lower heater 240a includes a support portion 241 provided horizontally as shown in the figure, a side portion 242 extending upward from the outside of the support portion 241 and provided with a plurality of holes, A lamp 243 and an adjuster 244 disposed under the support 241 to adjust the angle of the lamp 243. The upper dome 220a and the lower dome 220b may be formed of a metal, The internal reaction space can be divided into an upper region (a) and a lower region (b).

The raw material supply unit for supplying the reaction gas to the reaction space supplies the reaction gas injected through the head to the susceptor through an injection port in the form of a showerhead or the like.

A plurality of jetting ports are provided in the direction of the susceptor so that the reactive gas supplied through the head can be uniformly sprayed onto the entire surface of the susceptor 230 through the jetting ports.

The air supply unit 250 is disposed at a position corresponding to the lower portion of the chamber 210 and an inlet may be formed in the chamber 201 in an area where air is supplied from the air supply unit 250. An outlet is formed in the upper part of the chamber 210 to discharge air injected from the air supply part 250 through the inlet.

In contrast to the inlet formed at the bottom of the chamber 210, the outlet may be formed at the top of the chamber 210, and the inlet and outlet may be formed in opposite directions not only vertically but also horizontally.

In FIG. 2, an inlet may be formed on the right side of the chamber 210 and an inlet may be formed on the left side of the chamber 210. The inlet and outlet described above may be referred to as an 'air inlet' and an 'air outlet, respectively, and in the horizontal direction, the dome 220 may be interposed therebetween.

The operation of the graphene growth apparatus according to the embodiment will be described as follows.

The inside of the chamber 210 is heated to 800 ° C or higher by heating the lower heaters 240a and 240b so that hydrogen (H ₂ ), argon (Ar), or a mixed gas thereof is injected into the chamber 210 . The annealing process may be performed using hydrogen gas. The temperature inside the chamber 210 may be gradually lowered through the annealing process to lower the hardness and strength of the material.

When the temperature inside the chamber 210 is lowered at the initial stage of the process, only the lower portion of the reaction region can be cooled, and air or cooling water may flow into the cooling pipes 225b and 228b shown in FIGS. 7 and 8 , If the top of the reaction zone is cooled, the temperature of the susceptor may drop and the efficiency of the heater may be reduced.

Methane CH4 may be supplied into the chamber 210 to diffuse the metal catalyst to the carbon component. At this time, copper (Cu) or nickel (Ni) may be used as the metal catalyst .

The carbon contained in the metal can be removed by a method such as outdiffusion while lowering the temperature in the chamber 210.

At this time, air can be supplied from the air feeder 250 into the chamber 210, as shown in FIG. 2, in order to remove heat inside the chamber 210 heated to a temperature of 800 ° C or higher. The cooling speed of the inside of the chamber 210 can be maintained at 5 DEG C / sec or more in the above-described graphene growth apparatus, Lt; RTI ID = 0.0 > 10 C / sec. ≪ / RTI >

As shown in FIG. 2, since the air supplied through the inlet on the lower left side is discharged through the outlet on the upper right side, cooling can be performed in the entire region inside the chamber 210.

That is, air or cooling water can flow into the cooling pipes 225a, 225b, 228a, and 228b shown in FIGS. 7 and 8. If the upper and lower portions of the reaction region can be uniformly cooled, speed is maintained at 5 ° C / sec. to 10 ° C / sec. or less, so that graphene can be grown by out-diffusion of carbon due to pore contraction of a metal catalyst.

If the cooling rate is too high, the carbon can not sufficiently escape, the pores become clogged, and the graphene is not formed or becomes uneven. If the cooling rate is too high, cracks are formed in the grown graphene or the surface is rapidly shrunk, FIG. 3 is a graph showing changes in volume and temperature of air supplied to the graphene growth apparatus.

The volume of air supplied to the chamber, as shown (V _a) is a temperature increase of air over time (T _a) may be reduced over time.

4 is a view showing an air supply unit of the second embodiment of the graphene growth apparatus. The same shape as the graphene growth apparatus of FIG. 2, but only the shape shown in the region adjacent to the air supply unit may be different.

The air injection port is connected to the air supply unit 250 and includes an air injection port 255a and a second air injection port 255b. The air injection port includes a first air injection port 255a and a second air injection port 255b. The jetting ports 255b may have different jetting angles of air.

The first air injection port 255a and the second air injection port 255b are connected to each other through the air supply unit 250 and the air supply pipe 251 so that air can be supplied to the first air injection port 255a. Valves 256a and 256b may be disposed in the air injection port 255b, respectively.

4, when the valve 256a in the first air injection port 255a of the chamber 210 is opened, air is supplied in an upward direction of the chamber 210, And the valve 256b in the second air injection port 255b of the chamber 210 is opened so that air is supplied in a downward direction of the chamber 210 so that the lower region of the chamber 210 Can be further cooled.

5 is a view showing an air supply unit of a third embodiment of the graphene growth apparatus.

2, a power control unit is provided in the air supply unit 250 to control the speed at which air is supplied from the air supply unit 250 to the chamber 210.

That is, the power controller can control the cooling rate inside the chamber 210 by adjusting the volume V _a of the air supplied to the chamber 210 as shown in FIG.

Fig. 6 is a view showing an air supply unit of a fourth embodiment of the graphene growth apparatus, which is the same as the graphene growth apparatus of Fig. 2, in which water is arranged adjacent to the air supply unit.

That is, the temperature of the air supplied from the air supply unit 250 can be adjusted through the water, and the air whose temperature is lowered by the cooling water is supplied into the chamber 210, The temperature can be cooled.

7 is a view showing an air supply unit of a fifth embodiment of the graphene growth apparatus. 2, the cooling tube 225a is disposed in the upper dome 220a inside the chamber 210, and the cooling medium flowing in the cooling tube 225a The upper dome 220a can be cooled directly by the action of water.

A cooling pipe 225b is disposed in the lower dome 220b inside the chamber 210 so that the lower dome 220b can be cooled directly by the action of water flowing inside the cooling pipe 225b .

The cooling pipe 225 may receive cooling water from the outside of the chamber 210 though the cooling pipe 225 is not shown and the cooling water is directly contacted with the upper dome 220a made of quartz, Fig. 8 is a view showing the air supply unit of the sixth embodiment of the graphene growth apparatus.

2, the cooling tube 228a is disposed around the upper dome 220a inside the chamber 210, and the inside of the cooling tube 228a The upper dome 220a can be cooled directly by the action of water flowing through the upper dome 220a.

A cooling pipe 228b is disposed around the lower dome 220b in the chamber 210 to directly cool the lower dome 220b by the action of cooling water flowing in the cooling pipe 228b .

The cooling pipe 225 may receive cooling water from the outside of the chamber 210 though the cooling pipe 225 is not shown and the cooling water contacts the surface of the upper dome 220a made of quartz or the like, To quickly cool the area inside the upper dome 220a.

In the embodiment shown in FIGS. 7 and 8, the cooling pipes 225 and 228 may be disposed inside or on the upper dome 220a to cool the upper dome 220a directly by the flow of the cooling water. The cooling tubes 225 and 228 may be made of a material capable of withstanding high temperatures such as a sustain system or a ceramic system or a graphite system. In addition to the water, air may flow inside.

The graphene growth apparatus described above is operated by growing the graphene by a CVD process and by operating the air supply unit off in the temperature raising process of the chamber and the dome, The cooling speed of the inside of the chamber can be increased to 5 DEG C / sec or more without using a separate cooling module, and particularly, / RTI > / sec, so that the thickness of the graphene grown on the susceptor is uniform and the occurrence of cracks can be prevented.

The air supplied from the air supply unit can be supplied to other areas of the chamber through the first air jet opening and the second air jet opening with different jetting angles and the amount of cooling water or air supplied to the chamber by the action of the power control unit and the cooling water And temperature can be adjusted.

The graphenes grown in the above-described graphene growth apparatus are excellent in quality because they do not crack uniformly in thickness, and can be used for display materials such as organic light emitting devices (OLEDs), in particular, indium tin oxide ; ITO). ≪ / RTI >

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

100, 200: graphene growth apparatus 110, 210: chamber
120: Dom 130, 230: Susceptor
140: Heater 150, 250: Air supply
215: chamber body 220a: upper dome
220b: Lower dome
225a, 225b, 228a, 228b:
235: drive shaft 238: drive device
240a, 240b: lower heater 241:
242: side portion 243: lamp
244:
251: air supply pipe 255a: first air jet opening
255b: second air injection port 256a, 256b: valve

Claims (11)

chamber;
A dome disposed within the chamber and having a susceptor disposed therein and forming a closed space;
A raw material supply unit disposed inside the dome and supplying the raw material gas toward the susceptor;
A heater for heating the dome; And
And an air supply unit for supplying air into the chamber,
Wherein an air inlet is formed in a lower region of the chamber and an air outlet is disposed in an upper region of the chamber so as to face the air inlet with the dome therebetween. delete The method according to claim 1,
Further comprising an air injection port connected to the air supply unit and supplying air into the chamber, wherein the air injection hole includes a first air injection port and a second air injection port with different air injection angles. The method of claim 3,
Further comprising valves disposed in the first air ejection port and the second air ejection port, respectively. The method according to claim 1,
And a power control unit for adjusting a supply amount of air supplied from the air supply unit to the chamber. The method according to claim 1,
And cooling water for cooling air supplied from the air supply unit to the chamber. The method according to claim 1,
And a cooling tube disposed inside the dome. The method according to claim 1,
And a cooling tube disposed on an outer surface of the dome. 9. The method according to claim 7 or 8,
Wherein air or cooling water flows through the inside of the cooling tube. 9. The method according to claim 7 or 8,
Wherein the dome is made of quartz. 9. The method according to claim 7 or 8,
Wherein the cooling tube is made of a material of a sustain type, a ceramic type or a graphite type.

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