KR102447531B1 - A Spheroid of Ntrides-based Nanocomposite, having a Single or Multi Core-Shell Structure - Google Patents

Abstract

The present invention relates to a nitride-based nano-fusion spheroid having a core-shell structure capable of exhibiting the properties of a spherical body (quantum dot), and more specifically, nano-crystallization and shell of a core raw material by a plasma method It relates to a nitride-based nanofusion spheroid of a single or multiple core-shell structure manufactured through a spheroidization process of a raw material and various uses thereof.

Description

A Spheroid of Ntrides-based Nanocomposite, having a Single or Multi Core-Shell Structure

The present invention relates to a nitride-based nano-fusion spheroid having a core-shell structure capable of exhibiting the properties of quantum dots, and more specifically, nano-crystallization of a core raw material by a plasma method and a shell raw material The present invention relates to a nitride-based nanofusion spheroid of a single or multiple core-shell structure made of a single crystal unit prepared through a spheroidization process of a material, and various uses thereof.

Research over the past few decades has laid the groundwork for a broadly defined new direction of nano science and technology, and has endeavored to combine the two. These nanotechnology studies are still being actively pursued because of their unique and fascinating properties as well as complementary applications for bulk materials. This is because newly made nanomaterials exhibit significantly improved properties (optical properties, strength, elasticity, thermal and electrical conductivity, etc.) compared to conventional bulk and thin film materials, and can contribute a lot to the miniaturization of devices. .

Among these nanomaterials, quantum dots are semiconductor nanoparticles having a zero-dimensional spherical shape, and despite being the same material, they exhibit different optical and electrical properties from bulk materials. The reason is that as the size of the material decreases, the band consisting of the continuous energy state of the original inorganic crystal changes discontinuously, and the properties change.

In particular, quantum dots are attracting attention because they can emit a variety of spectra with high quantum efficiency and excellent color purity through material size control compared to fluorescent dyes, and because they are not organic materials, they can also ensure photostability. In addition, research on quantum dots capable of emitting light in various wavelengths as well as in the visible light region is being conducted, and research for applying them to solar cells, bioimaging, light emitting diodes, and photodetectors is also being actively conducted.

In particular, quantum dot LED (quantum dot light emitting diode, QD-LED) using the same has good color purity, excellent color reproducibility, and is capable of realizing a large-area high-resolution display with good video characteristics, so a lot of research is being conducted.

Group II-VI compound semiconductors with high quantum efficiency and excellent stability are mainly used as quantum dot light emitting materials for QD-LEDs. ) structured quantum dot materials have been extensively studied due to their high PL (photoluminescence) quantum efficiency. However, since the core component of the quantum dot is made of Cd, which is harmful to the environment and the human body, research on a Cd-free group III-V semiconductor quantum dot material and an LED device using the same is being actively conducted. Therefore, group III-V quantum dots, which are non-toxic and eco-friendly quantum dots, have been in the spotlight, but effective mass synthesis methods for group III-V quantum dots have not yet been reported.

In particular, there have been few studies so far on synthesizing core-shell structured quantum dots or similar structures using non-cadmium-based materials, In, Ga, Al, and nitride.

Accordingly, the present inventors used In, Ga, Al and Nitride, which are non-cadmium-based materials that were difficult to make with a conventional core-shell structure, similar to quantum dots that can exhibit properties similar to those of conventional quantum dots. As a structure, it was confirmed for the first time that a nitride-based nano-fusion spheroid having a single or multiple core-shell structure composed of a single crystal unit can be synthesized, and the present invention was completed.

Patent Document 1: Republic of Korea Patent Registration 10-1043311 Patent Document 2: Korean Patent Publication No. 10-2011-0059855 Patent Document 3: Korean Patent Publication No. 10-2012-0019955 Patent Document 4: Republic of Korea Patent Registration 10-1436099

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An object of the present invention is a single crystal unit using a nitride-based material, preferably an In-Ga-Al-N-based material, which is a non-cadmium-based material that has been difficult to make into a conventional core-shell structure. It is to provide a nitride-based nano-fusion spheroid of a single or multiple core-shell structure consisting of.

Another object of the present invention is to provide various uses of the nitride-based nano-fusion spheroid having the single or multiple core-shell structure.

Another object of the present invention is to provide a method for synthesizing the nitride-based nano-fusion spheroid of the single or multiple core-shell structure using a plasma method.

In order to solve the above problems, the present invention

consisting of single crystal units,

Provided is a nitride-based nanofusion spheroid forming a single core-shell or multiple core-shell structure.

The spherical body may be spherical or protruding including irregular oval, amorphous, and regular spherical shapes.

The single core-shell structure spheroid preferably has a core having a diameter of 1 nm to 10 nm and a shell having a thickness of 0.1 to 10 nm, and the multi-core-shell structure has a spheroid having a diameter of 1 nm to 10 nm. It is preferable to have a spherical or protruding structure in which at least 2 of the cores are impregnated in a shell having a diameter of 100 nm to 1 μm. At this time, in the spherical body of the multi-core-shell structure, about 100 to 50,000, 500 to 50,000, preferably 500 to 40,000, more preferably 500 to 30,000 of the cores are impregnated into the shell. there may be

In particular, the present invention is a non-cadmium-based material using a nitride-based material, more preferably In, Ga, Al, and nitride (N), which has been difficult to make into a conventional core-shell structure. It is characterized by providing a structure that solves the problem.

The core of the spheroid may be a III-V material, preferably III-V nitrides. Specific examples include at least one material selected from the group consisting of InN, InP, GaAs, GaP, GaInN, GaN and InGaAlN, and more preferably InN and/or GaInN.

The shell of the spheroid may also be a III-V material, preferably III-V nitrides. As a specific example, it may be at least one selected from the group consisting of GaN, InN, AlN, and AlGaN, and most preferably, GaN and/or AlGaN is used.

In one embodiment of the present invention, the core material of the spheroid is GaN, and the spheroid shell material is InN.

Therefore, the most preferred example of the core-shell structure spheroid of the present invention is a nitride-based, that is, an In-Ga-Al-N-based nano-fusion spheroid characterized by being composed of In, Ga, Al and N. . These nitride-based spheroids have the advantage of very high thermal stability.

The present invention also provides, as another embodiment, a method for synthesizing the nitride-based nanofusion spheroid of the core-shell structure, comprising:

Plasma method is used,

forming a nano-crystallized core by vaporizing at least one spherical core material selected from the group consisting of InN, GaInN, GaN and InGaAlN at a first temperature of 5000 to 10000° C.; and

GaN, AlN, and at least one spherical shell material selected from the group consisting of AlGaN is vaporized or liquefied at a second temperature of 500 ~ 4000 ℃ spheroidizing the shell surrounding the core.

Preferably, the plasma method uses a thermal plasma method.

At this time, providing the first temperature and the second temperature may be carried out by injecting the raw material for forming the core and the shell of the spherical body at different heights in the plasma reaction chamber using tubes having different lengths, respectively. have.

In addition, as another embodiment, the present invention provides various uses of the nitride-based, that is, In-Ga-Al-N-based nano-fusion spheroids.

In particular, the nitride-based nano-fusion spheroids of the present invention can exhibit excellent light emitting properties of quantum dots, and have high thermal stability, as well as excellent dispersibility because aggregation between the spheroids does not occur well. Therefore, it will be able to be widely used with better physical properties in the field to which the conventional quantum dots have been applied.

The present invention is a single crystal unit excellent in stability, dispersibility and luminescence by using In, Ga, Al, and nitride-based materials, which are non-cadmium-based materials that have been difficult to make into a conventional core-shell structure. By making it possible to provide a nano-fusion spheroid of a single or multi-core-shell structure made of

1 is a schematic diagram of a nitride-based, more preferably In-Ga-Al-N-based spheroid having a single or multi-core-shell structure of the present invention.
FIG. 2 is a schematic view showing a feature including a dual tube according to a temperature gradient in the manufacture of a spheroid of a core-shell structure of the present invention.
3 to 4 are TEM images of nitride-based nanofusion spheroids having a multi-core-shell structure, which is an embodiment of the present invention.
5 is a TEM-EDS analysis result of a nitride-based nano-fusion spheroid having a multi-core-shell structure, which is an embodiment of the present invention.
6 is a result of confirming the light emission characteristics using a UV-Lamp of 312nm wavelength.

"Nanomaterial" refers to a material that uses the size dependence of physical properties in the nanometer size region (1 to 100 nanometers), and the application of these nanomaterials is in the form of a powder, a tube or a whisker. It is possible in various forms, such as a form, a thin film form, and a bulk form.

As used herein, "about" refers to 30, 25, 20, 25, 10, 9, 8, 7, 6, means an amount, level, value, number, frequency, percent, dimension, size, amount, weight or length varying by 5, 4, 3, 2 or 1%.

Throughout this specification, unless the context requires otherwise, the terms "comprises" and "comprises" include the steps or elements, or groups of steps or elements presented, but any other step or element, or step or element. It should be understood to imply that a group of these is not excluded.

The present invention relates to a nitride-based nano-fusion spheroid having a core-shell structure capable of exhibiting the properties of quantum dots.

In particular, cadmium (Cd) is not used (Cd-free), nitride-based (Nitride) material, preferably in the nano-fusion spheroid of a single or multiple core-shell structure made of an In-Ga-Al-N-based material. it's about

Therefore, in one aspect, the present invention relates to a spherical or protruding nitride-based nanofusion spheroid having a single or multiple core-shell structure.

Most preferably, it relates to a spherical In-Ga-Al-N-based spheroid having a single core-shell structure or a multi-core-shell structure.

The "single core-shell structure" means a structure according to Schematic A of FIG. 1, consisting of a single core and a single-layered shell structure surrounding the same, and "multi-core-shell structure" means a plurality of cores and surrounding them. It means the structure according to the schematic diagram B of FIG.

The nitrite-based nanofusion spheroids of the present invention include both spheroids having a single core-shell structure and spheroids having a multi-core-shell structure.

The "nano-fusion spheroid" of the present invention refers to a spherical unit having a nanometer-sized region (1 to 100 nanometers) or a spheroidized structure in which they are fused and spheroidized. In the present invention, it is preferably Units having a diameter of about 1 to 50 nm, 1 to 40 nm, 1 to 30 nm, 1 to 20 nm, 1 to 10 nm, and spherical or protruding units with a diameter of 100 nm to 1 μm formed by fusion of them Includes all structures.

In addition, although "nitride-based material" of the present invention refers to a material containing nitrogen as an anion, in the present invention, not only pure nitride but also oxynitride may be used. Any known method may be used as a method for producing it, for example, ammonothermal synthesis may be used. Since ammonia has similar physical properties to water than any other solvent, the ammonothermal synthesis technique is advantageous for synthesizing a nitrogen-based compound. The nitride-based material exhibits excellent electron mobility, dielectric breakdown voltage, saturation electron velocity, and thermal conductivity, and thus has many possibilities as a high-frequency, high-output transistor material. In addition, since there is no need to worry about the depletion of N resources, it has the advantage of promising as a future material.

In addition, the "nano-fusion spheroid" of the present invention is characterized in that it consists of a material of a single crystal unit. That is, the core and shell structures forming the spheroid are composed of single crystal units having such a periodically arranged atomic structure. It was extremely impossible to grow a crystal from a generally known melt, and in some studies, it was formed in a bulk form by reacting a group III-V material with N ₂ gas in a high-temperature and high-pressure atmosphere, but the crystallinity was poor. Although there was a problem, the spherical body of the present invention forms a crystal with high efficiency, which is made of a single crystal unit.

Hereinafter, a single core-shell structure will be described in more detail.

core( Core )

The core of the spheroids of the present invention consists of a single crystal group III-V material, more preferably a III-V nitrides material, and when combined with the shell, a luminescent structure is produced.

Specific examples include at least one material selected from the group consisting of InN, GaInN, GaN, and InGaAlN, and most preferably, InN and/or GaInN are used, but the present invention is not limited thereto. In one embodiment of the present invention, InN is used. The core may include two or more elements.

In terms of optical properties, InN has a wide band gap energy of 0.7 to 1.9 eV, and GaInN compounds have optical and electrical properties advantageous for optoelectronic devices, such as high electron mobility and high saturation rate.

In one embodiment, the core can have a diameter of about 1 nm to 40 nm, about 1 nm to 30 nm, about 1 nm to 20 nm, or about 1 nm to 10 nm, preferably about 1 nm to 10 nm.

shell ( Shell )

The shell of the spheroid of the present invention is a semiconductor that is different from the semiconductor of the core and is combined with the core to form a surface layer of the core. The shell usually passivates the core by having a higher bandgap than the core.

The shell structure of the present invention may be single-crystal III-V nitrides or III-V oxides, preferably III-V nitrides.

For example, one selected from the group consisting of aluminum oxide, silicon oxide, silicon nitride, silicon oxynitride, magnesium oxide, indium oxide, hafnium oxide, zinc oxide, tin oxide, titanium oxide, manganese oxide, tungsten oxide, and magnesium fluoride species can be used. As a more preferable example, SiO ₂ , Al ₂ O ₃ , ZnS, GaN, InN, AlN, AlGaN, or the like may be used. Even more preferably, GaN, AlN, and AlGaN, most preferably GaN and/or AlGaN may be used, but not limited thereto. In an embodiment of the present invention, GaN was used.

The GaN is a semiconductor and a very hard material with a Wurtzite crystal structure. The wide band gap is 3.4 eV, and the light generated in the 3.4 eV band gap is light corresponding to a wavelength of blue to purple, and because of these characteristics, photoelectrons ( It can be mainly used in optoelectronic, high-power & high frequency devices or light emitting diodes.

In one embodiment, the size of the shell in a single core-shell structure may be about 0.1-10 nm thick, about 0.1-5 nm thick, or about 0.1-2 nm thick (FIG. 1A).

multi-core shell structure nitride system nano fusion spheroid

On the other hand, the present invention may have a protrusion or spherical shape with a diameter of 100 nm to 1 μm, including a plurality of the single core, from another viewpoint. This is referred to herein as a nitride-based nanofusion spheroid of a multi-core shell structure composed of single crystal units.

The spherical shape includes both irregular oval, amorphous, and regular spherical shapes.

The multi-core-shell structure has, for example, a structure in which a plurality of (plural) cores having a diameter of about 1 nm to 10 nm are impregnated in a shell structure having a diameter of 100 nm to 1 μm ( FIG. 1B ).

In the multi-core-shell structure spheroid, there are hundreds, thousands, or tens of thousands of single cores with a diameter of 0.1 to 10 nm, that is, about 100 to 50000, preferably 500 to 50000, more preferably in the shell. about 500 to 40,000 may be impregnated. For example, several hundred or more single cores, such as 500-30000, 500-20000, 500-10000, 1000-30000, 1000-20000, 1000-10000, etc., may be impregnated in the shell.

As the most preferred embodiment in the present invention, a nitride-based nanofusion spheroid having such a multi-core-shell structure may be mentioned.

In particular, the multi-core-shell quantum dots of the present invention solve the problem of conventional nano-sized quantum dots agglomerated with each other and difficult to disperse.

That is, since the multi-core-shell quantum dots having a diameter of 100 nm to 1 μm are in the form of impregnated nano-sized core particles on the surface, agglomeration does not occur, so they are easy to disperse and have the advantage of being stable in the atmosphere.

Therefore, the multi-core-shell quantum dot of the present invention also solves the cumbersome problem in which an additional process of imparting a different functional group to the surface was required in the prior art in order to prevent the aggregation due to the nano size.

In addition, since the quantum dots of the multi-core-shell structure include a plurality of cores and form a shell structure surrounding them, the desired optical and electrical properties can be maximized, and the efficiency and stability of the quantum dots can be increased together. have.

As such, the nitride-based nano-fusion spheroid as a preferred embodiment of the present invention consists of a single crystal unit, GaN / InN, GaInN / AlGaN, InN / AlN, GaInN / AlN, InN / AlGaN, such as core-shell structure spheres include That is, the nitride-based nano-fusion spheroid of the present invention is characterized in that it consists of In, Ga, Al and N.

Therefore, in addition to the toxicity problem of the conventional cadmium-based quantum dots, the synthesis is also unfriendly, and only a small amount that is difficult to industrialize is possible, which solves the problem that was acting as a big obstacle to commercialization.

In short, the following technical advantages can be achieved:

(i) It can be used as an eco-friendly quantum dot-like structure that has excellent luminous efficiency and stability and is not toxic like cadmium.

Quantum dots with excellent efficiency that are currently commercialized are made of cadmium compounds, so there are concerns about toxicity to the environment and the human body. QLED can be developed.

(ii) A thin film in which the spheroids of the present invention are uniformly distributed can be produced.

Although the surface of the conventional quantum dot is covered by a short organic ligand, it is difficult to form a uniform light emitting layer because the quantum dots (QD) are agglomerated with each other when forming a thin film. And in order to develop a QD film, it is necessary to uniformly disperse the QD in a polymer matrix, which is difficult because phase separation occurs well.

However, if the nitride-based nano-fusion spheroid having a multi-core shell structure of the present invention is used, there is no such aggregation and has excellent dispersibility, so that a uniform thin film can be manufactured.

(iii) The nitride-based nano-fusion spheroid having a multi-core shell structure of the present invention including a plurality of cores can simultaneously increase the efficiency and lifespan of a conventional QLED.

Therefore, the present invention in another aspect relates to various uses of the nanofusion spheroids of single or multiple core-shell structure made of the above nitride material, preferably In-Ga-Al-N-based material.

In particular, the nitride-based nano-fusion spheroid having a single or multiple core-shell structure of the present invention can exhibit the properties of quantum dots known in the prior art and their improved properties.

That is, the spherical body of the present invention exhibits very different changes in physical properties compared to the bulk state of the solid and general organic compounds, and based on these properties, has infinite application potential in various fields such as electronics, energy, and medicine.

In one embodiment, the wavelength-converted excitation light of a light emitting diode (LED) may be used in a spherical body for an LED to generate wavelength-converted light.

In another embodiment, when the spherical body is used in a solar cell, it may be possible to manufacture a low-cost solar cell through a simpler process. In particular, it is possible to absorb sunlight from short to long wavelengths according to the size control of the spherical body, so that it is possible to absorb light in a much wider area than conventional solar cells, thereby covering the entire solar spectrum. Next-generation solar cells that exhibit higher efficiency than cells can be developed.

In another embodiment, among the applications of spheroids, the application in the field of bio devices has many expectations. The size of the spheroid is similar to the size of an important molecule or protein in the living body, and it can be adjusted to emit a wavelength in the accurate visible range according to the size, so it can be effectively used for cell imaging and drug delivery. have. In other words, if a biomarker that responds to a specific cell is attached to the spheroid, imaging and tracking of the cell is possible, and cancer diagnosis and treatment can be performed using the biomarker. Therefore, the development of biocompatible spheroids and biomarkers that respond to specific cells should be prioritized. On the other hand, spheroids have a high potential for use as a gene or drug delivery medium because they may have the ability to track cells affected by a specific disease.

In addition, it may be utilized in various fields of various nanomaterials.

In addition, the present invention from another viewpoint

vaporizing the quantum dot core material using a plasma method, preferably using a thermal plasma method, at a first temperature to form a nano-crystallized core; and the quantum dot shell material is vaporized or liquefied at a second temperature lower than the first temperature to spheroidize into a shell surrounding the core.

In one embodiment, it relates to a method for synthesizing nitride-based nanofusion spheres with single or multiple core-shell structures, comprising the steps of:

Plasma method is used,

forming a nano-crystallized core by vaporizing at least one spherical core material selected from the group consisting of InN, GaInN, GaN and InGaAlN at a first temperature of 5000 to 10000° C.; and

GaN, AlN, and at least one spherical shell material selected from the group consisting of AlGaN is vaporized or liquefied at a second temperature of 500 ~ 4000 ℃ spheroidizing the shell surrounding the core.

The plasma method may be performed by a person skilled in the art by appropriately modifying a known method.

For example, but not limited to, high frequency thermal plasma (RF) may be used, which may produce uniform nanoparticles.

However, preferably, in order to provide the first temperature and the second temperature, the raw material for forming the core and the shell of the spherical body is injected at different heights in the plasma reaction chamber using tubes having different lengths, respectively. can be carried out with

That is, by utilizing the temperature gradient function in the thermal plasma method to simultaneously or continuously provide each temperature environment required for core formation and shell formation of quantum dots, a single or multiple core-shell structure nitride-based nanofusion spheroids can be synthesized in situ (FIG. 2).

A brief explanation of the synthesis principle is as follows:

The raw material powder of the shell is injected through a long tube in the low-temperature part of the lower part of the plasma reaction part, preferably in the second low-temperature environment of about 4000 ° C. Partial vaporization or liquefaction is made, and it binds to the nanocrystals of the core material to form a spherical shell structure according to capping or a spherical or protruding shell structure with a diameter of 100 nm to 1 μm in which a plurality of cores are impregnated. .

The spheroids obtained by this plasma method can be obtained by mixing quantum dots of a single core-shell structure and quantum dots of a multi-core-shell structure. In addition, according to this method, since it is possible to continuously supply a relatively large amount of raw material, continuous and mass production of spheroids is possible.

Example

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention, and it will be apparent to those of ordinary skill in the art that the scope of the present invention is not to be construed as being limited by these examples.

production example One: Ga - In -N-based nano fusion globular Produce

Ga-In-N-based nano-fusion spheroids were prepared using an RF thermal plasma device.

Argon gas was used as a central gas, a sheath gas, a carrier gas, and a quenching gas to be introduced into the plasma processing apparatus, and ammonia and nitrogen gas for inducing a nitridation reaction were mixed and introduced to generate nitride.

Specifically, argon gas as the central gas was introduced at a flow rate of 30 L/min, and ammonia gas for inducing a nitridation reaction was introduced at 80 L/min as the sheath gas by mixing 5 L/min. In addition, nitrogen gas was injected at a flow rate of 10 L/min as a carrier gas for transporting raw materials InN and GaN.

The quenching gas for rapid cooling was injected at a rate of 280 L/min from 48 nozzles with a diameter of about 1 mm installed in the wall supply section using argon gas, and a separate quenching nozzle was introduced from the bottom in the center. Thus, it was additionally added at the same location at a flow rate of 100 L/min.

On the other hand, as the applied power for generating plasma, 20 kW was applied based on DC plate power to generate high-temperature thermal plasma, and the pressure inside the system was maintained at 200 torr.

In the plasma electrode part, dual tubes having different lengths were mounted and used for raw material injection. InN, a spherical core raw material, was injected into a short-length injection tube through a stepped nozzle, and GaN, a spherical shell raw material, was injected into a long-length injection tube, respectively, and the injection mass ratio was adjusted to about 1: 2 did.

At this time, the nozzle of the short injection tube was positioned at the center height of the electrode, which is 20 cm below the top of the electrode, and the nozzle of the long injection tube was installed 38 cm below the top of the electrode.

By installing in this form, the nozzles are positioned in the middle of the hot zone past the electrode part, so that InN injected from the short injection tube is completely vaporized and descends, and the GaN injected into the long injection tube is partially vaporized while Most of the surface was allowed to come down while maintaining the molten droplet state.

Next, a quenching gas was injected into the quenching part and cooled to obtain a mixture of nitride-based nanofusion spheroids having a single or multiple core-shell structure.

The quenching gas forms the nanofused spheroids of the present invention with single or multiple core shell structures while performing two roles: (i) cooling for InN to stop nucleation at a few nanoscales. role, and (ii) inducing collisions between these particles by creating a complex flow of fluid by quenching gas introduced from the side and from bottom to top.

The prepared, fused spheroids were moved according to the fluid flow and adsorbed on the metal sintered filter of the collector, and the adsorbed particles were separated through a blowback process in which a high-pressure gas was instantaneously blown in the opposite direction to the fluid flow of the adsorption process. . Then, by moving to the bottom by free fall, it was collected and obtained through the collecting unit.

Example 1: Transmission electron microscope ( TEM ) by analysis

The obtained nano-fusion spheroids were analyzed using a transmission electron microscope (TEM), and images were obtained and shown in FIGS. 3 to 5 .

As shown in FIG. 3 , it was confirmed that single cores having a total diameter of about 10 nm were impregnated like projections on the surface of a large shell. (Red circle: single core part, yellow circle: single shell part)

In addition, from the TEM image, as shown in FIG. 4 , it was found that several nm of InN was attached to the surface of GaN particles of about 200 nm, and the theoretical bonding distance of InN, (101) plane, 2.693 Å, (002) It can be seen that the measured bonding distances of the spheroids prepared by the present invention for the plane 2.845 Å are consistent as 2.818 Å, 2.647 Å, and 2.735 Å.

In addition, the result confirmed by performing component mapping in conjunction with an Energy Dispersive X-ray Spectroscopy (EDS) equipment is shown in FIG. 5 .

As a result, it was confirmed that, as indicated by the previous experimental data, a multi-core shell structure in which a small core InN component was bonded to the surface of a large shell structure of GaN component was formed.

Example 2: Confirmation of luminescence characteristics

The light emitting properties of the obtained Ga-In-N-based nano-fusion spheroids were confirmed.

As a result of confirming the luminescence characteristics using a UV-Lamp having a wavelength of 312 nm, as shown in FIG. 6 , it was possible to confirm the luminous ability of blue/green/red.

This means that the Ga-In-N-based nano-fusion spheroids of the present invention have light-emitting properties similar to those of conventional quantum dots.

The foregoing description of the present application is for illustration, and those of ordinary skill in the art to which the present application pertains will understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present application. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and likewise components described as distributed may also be implemented in a combined form.

The scope of the present application is indicated by the claims described below rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present application. .

Claims (14)

consisting of single crystal units,
Nitride-based nanofusion spheroids forming multiple core-shell structures.
According to claim 1,
The spheroid is a nitride-based nano-fusion spheroid, characterized in that the spherical or protrusion.
delete The multi-core-shell structure of claim 1, wherein the
A nitride-based nano-fusion spheroid, characterized in that the core 2 or more having a diameter of 1 nm to 10 nm is impregnated in a shell having a diameter of 100 nm to 1 μm.
5. The method of claim 4, wherein the multi-core-shell structure is
Nitride-based nano-fusion spheroids, characterized in that the core is in the form of 100 to 50,000 impregnated shells.
The method of claim 1,
The spheroid is a nitride-based nano-fusion spheroid, characterized in that consisting of In, Ga, Al and N.
According to claim 1,
Nitride-based nano-fusion spheroids, characterized in that the core of the spheroids is a III-V nitride (Nitrides) material.
8. The method of claim 7,
The core of the spheroid is a nitride-based nano-fusion spheroid, characterized in that at least one material selected from the group consisting of InN, GaInN, GaN and InGaAlN.
The method of claim 1,
The shell of the spheroid is a nitride-based nano-fusion spheroid, characterized in that the III-V nitride (Nitrides) material.
10. The method of claim 9,
The spheroid shell is a nitride-based nano-fusion spheroid, characterized in that at least one material selected from the group consisting of GaN, InN, AlN, and AlGaN.
The method of claim 1,
The spheroid's core material is InN, and the spheroid shell material is GaN.
A method for synthesizing a nitride-based nanofusion spheroid of a core-shell structure according to claim 1, comprising:
Using the plasma method,
forming a nano-crystallized core by vaporizing at least one spherical core material selected from the group consisting of InN, GaInN, GaN and InGaAlN at a first temperature of 5000 to 10000° C.; and
GaN, AlN, and at least one spherical shell material selected from the group consisting of AlGaN is vaporized or liquefied at a second temperature of 500 ~ 4000 ℃ spheroidizing the shell surrounding the core.
13. The method of claim 12, wherein providing the first temperature and the second temperature comprises:
Method characterized in that it is carried out by injecting the raw material for forming the core and the shell of the spherical body at different heights in the plasma reaction chamber using tubes of different lengths, respectively.
13. The method of claim 12,
The plasma method is a method, characterized in that the thermal plasma method.

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