KR101930523B1 - Method for fabricating quantum dot using nanocluster and method for fabricating quantum dot film - Google Patents

Abstract

 A method of preparing quantum dots using the disclosed nanoclusters comprises reacting a Group III precursor solution comprising a Group III precursor and a solvent and a solution of a Group V precursor comprising a Group V precursor, a solvent and an amine to form a Group III-V semiconductor compound Preparing seed particles having crystallinity and containing the same semiconducting compound as the nano clusters; and reacting the seed particles with the nanoclusters to form seeds, Forming a quantum dot larger than the particle.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a quantum dot using nanoclusters and a method for manufacturing the same,

The present invention relates to quantum dots, and more particularly, to a method for manufacturing quantum dots using nanoclusters and a method for manufacturing quantum dots using the same.

Quantum dots are nanoparticles having a size of several tens of nanometers or less, which have semiconductor characteristics, and have properties different from those of bulk particles due to the quantum confinement effect. Specifically, the bandgap varies according to the size of the quantum dot, and the wavelength to be absorbed can be changed. The quantum confinement effect due to the small size exhibits new optical, electrical, and physical characteristics not seen in bulk materials. Therefore, studies have been actively made on a technique for manufacturing photoelectric conversion elements such as solar cells and light emitting diodes using such quantum dots.

Studies on typical II-VI compound semiconductor quantum dots have attracted much attention due to their advantages such as high luminescence efficiency and stability, but they contain Cd2 + and Se2- as well as cause problems in environmental hazard and toxicity , And biodegradation, it has been recently investigated that the ternary system of Group III-V and the ternary compound semiconductor quantum dots of Group I-III-V, which can replace the Ⅱ-Ⅵ QDs, Respectively.

However, in the case of a V-group precursor such as arsenide, it is difficult to stably control the size of a quantum dot due to its high reactivity, and it is difficult to grow it to a sufficient size.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a method for stably forming quantum dots using nanoclusters.

It is another object of the present invention to provide a method of manufacturing a quantum dot thin film using the quantum dot.

According to an embodiment of the present invention for achieving the object of the present invention, there is provided a method of manufacturing a quantum dot using a nanocluster, the method comprising: preparing a Group III precursor solution including a Group III precursor and a solvent, and a Group III precursor solution including a Group V precursor, Preparing a nanocluster having an amorphous phase comprising a III-V semiconductor compound by reacting a solution of a Group V precursor, preparing a seed particle having crystallinity and containing the same semiconducting compound as the nanocluster, And reacting the seed particles with the nanoclusters to form quantum dots that are larger than the seed particles.

According to one embodiment, the semiconducting compound comprises indium arsenide.

According to one embodiment, the semiconducting compound comprises a V-group precursor comprising tris trimethylsilylacenamide.

According to one embodiment, the amine comprises an amine having an alkyl chain of 6 or more carbon atoms.

According to one embodiment, the amine comprises at least one selected from the group consisting of octylamine, hexylamine, oleylamine, dioctylamine, dihexylamine, trioctylamine and trihexylamine.

According to one embodiment, the solvent of the V-group precursor solution comprises a hydrocarbon.

According to one embodiment, the volume ratio of the amine to the solvent in the V-group precursor solution is 30% to 70%.

According to one embodiment, the step of preparing the nanoclusters comprises: injecting the Group V precursor solution into the Group III precursor solution at 200 ° C. to 320 ° C. and injecting the Group III precursor solution and the Group V precursor solution Cooling the mixture, and allowing the reaction to proceed at 40 < 0 > C or lower.

According to one embodiment, the seed particles are obtained by reacting a Group III precursor solution comprising a Group III precursor and a solvent and a solution of a Group V precursor comprising a Group V precursor, a solvent and an amine.

According to an embodiment of the present invention, a method of fabricating a quantum dot thin film includes: forming a quantum dot thin film by coating a quantum dot particle on a substrate; and providing a ligand exchange composition comprising a ligand material in the quantum dot thin film, And exchanging the ligands of the particles.

According to the present invention, III-V group quantum dots can be formed by reacting seed particles using a nanocluster having sufficient reactivity and stability at the same time as a precursor. Therefore, growth and size control of the quantum dot is easy.

Further, in the process of forming nanoclusters and / or seed particles, the use of oleylamine as a surfactant improves the size uniformity of quantum dot particles, the yield of quantum dots and the efficiency of ligand exchange, thereby increasing the luminous efficiency.

1 and 2 are schematic views for explaining a method of manufacturing a quantum dot according to an embodiment of the present invention.
3 is a flowchart illustrating a method of manufacturing a quantum dot thin film according to an embodiment of the present invention.
4A is a graph showing an absorption spectrum of a quantum dot in Synthesis Example 3. Fig.
4B is a graph showing absorption spectra of quantum dots in Comparative Synthesis Example 3. Fig.
5 is a graph showing the normalized luminescence spectra of the quantum dots of Synthesis Example 3 and Comparative Synthesis Example 3. Fig.
6 is a graph showing the measurement of the impurity content and optical density of the quantum dots in Synthesis Example 3 and Comparative Synthesis Example 3. Fig.
FIG. 7A is a graph showing Fourier transform infrared (FTIR) measurement results of a thin film formed using quantum dots of Synthesis Example 3 before and after a ligand replacement process. FIG.
7B is a graph showing Fourier transform infrared (FTIR) measurement results of a thin film formed using quantum dots of Comparative Synthesis Example 3 before and after the ligand replacement step.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In this application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a part or a combination thereof is described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Method of manufacturing quantum dots using nanoclusters

1 and 2 are schematic views for explaining a method of manufacturing a quantum dot according to an embodiment of the present invention.

According to an embodiment of the present invention, seed particles 10 are grown by providing nanoclusters 20 to seed particles 10. As a result, the quantum dot 30 having a larger diameter than the seed particles 10 can be obtained.

The seed particles and the nanoclusters may include the same material and may be classified according to their size and physical properties.

For example, the seed particles and the nanoclusters may include semiconducting compounds capable of forming quantum dots, and may specifically include Group III-V compounds. For example, the seed particles and the nanocluster may be formed of a material selected from the group consisting of gallium phosphorus (GaP), gallium arsenide (GaAs), gallium antimony (GaSb), gallium nitride (GaN), aluminum phosphorus (InN), indium phosphide (InP), indium arsenide (InAs), indium antimony (InSb), indium nitride (InN), gallium phosphors Gallium arsenide nitrides (GaAsN), gallium antimony nitrides (GaSbN), aluminum phosphorescent arsenide (AlPAs), gallium arsenide nitride (GaAs) , Aluminum phosphorus antimony (AlPSb), aluminum phosphorus nitrides (AlPN), aluminum arsenide nitrides (AlAsN), aluminum antimony nitrides (AlSbN), indium phosphorous arsenide (InPAs) Aluminum gallium arsenide (AlGaAs), aluminum gallium arsenide (AlGaAs), indium gallium arsenide (AlGaAs), aluminum gallium arsenide (AlGaSb), aluminum gallium nitride (AlGaN), aluminum arsenide nitrides (AlAsN), aluminum antimony nitrides (AlSbN), indium gallium phosphors (InGaP), indium gallium arsenide (AlIn), aluminum indium arsenide (AlInAs), aluminum indium arsenide (InAsN), indium antimonitride (InSbN), aluminum indium phosphide (AlInP), aluminum indium arsenide (AlInSb), aluminum indium nitride (AlInN), aluminum arsenide nitrides (AlAsN), aluminum antimony nitrides (AlSbN), aluminum phosphorus nitrides (AlPN) , GaAlPAs, GaAlPb, GaInPAs, GaInAlAs, Gallium Aluminum Phosphorus Nitride (GaAlPN), Gallium Aluminum Phosphorus Nitride (GaAlPN) (GaAlAsN), gallium aluminum antimonitride (GaAlSbN), gallium indium phosphorus nitride (GaInPN), gallium indium arsenide nitride (GaInAsN), gallium indium aluminum nitride (GaInAlN), gallium aluminum gallium arsenide nitride (GaAsPPN), gallium arsenide phosphorus nitride (GaAsPN), gallium arsenide antimonitride (GaAsSbN), gallium indium phosphosphorus antimony (GaInPSb), gallium indium phosphorus nitride (GaInPN ), Gallium indium antimonitride (GaInSbN), gallium phosphorus antimonitride (GaPSbN), indium alum (InAlN), indium aluminum phosphonite (InAlN), indium aluminum phosphonite (InAlN), indium aluminum phosphonite (InAlN), indium aluminum phosphonite , Indium arsenide antimonitride (InAsSbN), and indium aluminum phosphorus antimony (InAlPSb).

In one embodiment, the seed particles and the nanoclusters may comprise indium arsenide.

The seed particles have crystallinity. For example, the seed particles may have a diameter of 2 nm or more and 3 nm or less. The nanoclusters may have a larger size distribution than the seed particles. For example, the nanoclusters may have a diameter of 1 nm to 4 nm and have an amorphous phase. Since the nanoclusters have an amorphous phase, they are unstable (easier to react) than crystalline particles. Therefore, it can function as a precursor for growing particles.

The seed particles can act as a nucleus in the course of quantum dot growth. The nanoclusters can bond to and react with the seed particles, and the growth of quantum dots can proceed. The nanoclusters are more stable than commonly known Group III precursors or Group V precursors and have reactivity to function as precursors for the growth of quantum dots. If quantum dots are to be formed only by the nanoclusters without the seed particles, nucleation takes a lot of time and a high temperature process is required, which is not preferable.

For example, the seed particles and the nanoclusters can be obtained by different methods.

The seed particles can be obtained by the reaction of the precursors. For example, the seed particles can be obtained by the reaction of Group III precursors and Group V precursors. For example, when preparing seed particles containing indium arsenide, an indium precursor and an arsenide precursor are reacted.

For example, the indium precursor may be at least one selected from the group consisting of indium chloride, indium chloride tetrahydrate, indium oxide, indium nitrate, indium nitrate hydrate, Indium sulfate, indium sulfate hydrate, indium acetate, indium acetylacetonate, indium bromide, indium fluoride, indium fluoride, Indium fluoride trihydrate, trimethyl indium, indium oleate, and the like. Preferably, the indium precursor may comprise indium acetate. The indium acetate reacts with oleic acid to form seed particles capped with oleate (or oleic acid), and seed particles capped with oleate may have stable dispersibility.

For example, the precursor may be tris (trimethylsilyl) -arsenide, (TMS) _3- As, arsenic trioxide, arsenic silylamide, For example, arsenic chloride, arsenic sulfate, arsenic bromide, and the like. Preferably, the arsenide precursor may comprise tris (trimethylsilyl) acetamide. Tris trimethylsilylacenamide has a much higher reactivity than other arsenide precursors.

According to an embodiment, the indium arsenide seed particle may be obtained by mixing the indium precursor solution containing the indium precursor and the arsenide precursor solution containing the arsenide precursor, followed by conducting the reaction.

For example, the indium precursor solution includes an indium precursor and a solvent. The solvent may be a non-reactive solvent which is not reactive with the precursor and may include, for example, a hydrocarbon. For example, as the hydrocarbon, hexane, dodecane, decane, undecane, tetradecane, hexadecane, 1-hexadecyne, 1-octadecyne, diphenyl ether and the like can be used. These may be used alone or in combination.

When indium oleate is used as the indium precursor, oleic acid is added for the synthesis of indium oleate. For example, indium (tri) acetate and oleic acid may be mixed in a solvent and then reacted at about 100 ° C to 150 ° C to obtain indium (trioleate).

For example, the above-described arsenide precursor solution includes an arsenide precursor, a solvent, and an amine. The solvent may be substantially the same as the non-reactive solvent used in the indium precursor solution.

The amine may serve as a surfactant to increase the size uniformity of the quantum dot particles. In addition, the amine may accelerate the reaction of the precursors to reduce the generation of impurities and increase the quantum dot production efficiency.

Preferably, the amine can be a primary amine, a secondary amine or a tertiary amine, more preferably an alkylamine having 6 or more carbon atoms, such as octylamine, hexylamine, oleylamine, dioctylamine, dihexylamine , Trioctylamine, trihexylamine, and the like.

For example, the content of the amine may be 30% to 70% based on the volume of the solvent.

In one embodiment, the indium arsenide seed particles may be formed at a high temperature and, in particular, may be formed by a hot injection method.

For example, after the temperature of the indium precursor solution is raised to 200 ° C. to 320 ° C., the precursor solution is rapidly injected with a syringe or the like, and crystals are grown at a temperature 40 ° C. to 60 ° C. lower than the temperature at the time of implantation , Seed particles can be synthesized.

In the above, a process for obtaining indium arsenide seed particles is described, and other precursors may be used depending on the material constituting the seed particles.

For example, the Group III precursor may be selected from the group consisting of aluminum acetate, aluminum iodide, aluminum bromide, aluminum chloride, aluminum chloride hexahydrate, Aluminum fluoride, aluminum nitrate, aluminum oxide, aluminum perchlorate, aluminum carbide, aluminum stearate, aluminum sulfate Di-i-butylaluminum chloride, diethylaluminum chloride, tri-i-butylaluminum, triethylaluminum, triethylaluminum, (Tri-sec-butoxy) dialuminium, trimethyl aluminum (tri-sec- Gallium acetylacetonate, Gallium chloride, Gallium fluoride, Gallium fluoride trihydrate, Gallium oxide, Gallium nitrate, gallium nitrate hydrate, gallium sulfate, gallium iodide, triethyl gallium, trimethyl gallium, and the like.

The V-group precursor may also be selected from the group consisting of alkyl phosphine, tris (trialkylsilyl phosphine), tris (dialkylamino phosphine), tris dialkylaminophosphine tris (dialkylamino) phosphine, nitric acid, ammonium nitrate, and the like.

The nanoclusters are formed at a lower temperature than the seed particles. For example, the nanoclusters can be formed at 40 占 폚 or lower, for example, at 20 占 폚 to 40 占 폚. When the temperature during the synthesis of the nanoclusters exceeds 40 캜, the crystallinity increases, and it is difficult to obtain physical properties and reactivity as clusters.

The method of preparing the nanoclusters may comprise the step of mixing the seed particles (a), except that the reaction temperature of the V-group precursor, for example, the indium precursor and the precursor of the precursor, May be the same as the method of preparing the sample. In addition, the reaction of the precursors may proceed under inert gas conditions such as nitrogen gas and the like.

Next, the seed particles are provided with the nanoclusters to grow crystals. For example, the step of reacting the seed particles with the nanoclusters may be performed at a high temperature. For example, a solution 15 containing seed particles at a high temperature (for example, 250 DEG C to 320 DEG C) is injected into the solution 15 using a hot injection method as shown in FIG. 2, A solution 25 containing the nanoclusters is injected.

As shown in Fig. 1, the nanoclusters 20 react with the seed particles 10 to grow the seed particles 10, thereby obtaining quantum dots 30. Although the nanoclusters have an amorphous phase, the quantum dots 30 having crystallinity through a growth reaction at a high temperature can be obtained.

The quantum dots 30 have a larger diameter than the seed particles 20. For example, the size of the quantum dot 30 may be more than 3 nm but less than 20 nm. The size of the quantum dot 30 can be controlled by the injection rate of the nanocluster solution, the reaction temperature, and the like.

According to the present invention, it is possible to form quantum dots by reacting seed particles using nanoclusters having sufficient reactivity and stability at the same time as precursors, instead of forming quantum dots from anionic precursors having high reactivity but low stability. Therefore, growth and size control of the quantum dot is easy.

In addition, according to the present invention, by including an amine in the V-group precursor composition, the size uniformity of the quantum dot particles can be increased, the reaction of the precursors can be promoted to reduce the generation of impurities and increase the quantum dot production efficiency.

Although the synthesis of group III-V quantum dots has been described in the above examples, the present invention can be applied to the synthesis of multi-element quantum dots of three or more elements, for example, Group I-III-V group quantum dots, But also to the synthesis of quantum dots having covalent bonds such as Si-Ge.

Manufacturing method of quantum dot thin film

3 is a flowchart illustrating a method of manufacturing a quantum dot thin film according to an embodiment of the present invention.

Referring to FIG. 3, first, quantum dot particles are coated on a substrate to form a quantum dot thin film (S10). The quantum dot particles may be obtained according to the quantum dot manufacturing method described above. Therefore, a detailed description thereof will be omitted. The quantum dot particles can significantly improve the ligand exchange efficiency.

The substrate may include glass, quartz, silicon, plastic, or the like. The plastic may include polyethylene terephthalate, polyamide, polydimethylsiloxane, polyethylene, polypropylene, polyimide, polyurethane, and the like.

The quantum dot particles may have a first ligand bound to the surface. The first ligand is an organic molecule, for example, an oleic acid ligand.

In one embodiment, to coat the quantum dot particles on the substrate, a composition comprising the quantum dot particles and a solvent may be coated on the substrate. For example, the solvent may include butanol, methanol, hexane, and the like.

The coating of the quantum dot particles may be accomplished through dipping, spraying, drop casting, self-assembly, spin coating, doctor blade, printing, and the like.

Next, the ligands of the quantum dot particles are exchanged (S20). For example, a ligand exchange composition comprising a ligand material in the quantum dot thin film can be provided. The ligand material can be strongly bound to the quantum dot and has a size smaller than that of the ligand originally bound. For example, the ligand material is an organic material, preferably having 3 or less carbon atoms, and more preferably 1 or 2 carbon atoms. Specifically, the ligand material to be exchanged may be ethanethiol, alkanedithiol such as ethanedithiol, hydrazine, hydroxylamine, and the like. At this time, the ligand material can be selected according to the quantum dot used. Specifically, for example, when the quantum dot particles include indium arsenide, ethanedithiol can be preferably used.

Thus, the quantum dot particles are bound to the second ligand smaller than the first ligand.

The step of exchanging the ligands of the quantum dots may be performed by dipping, spraying, drop casting, self-assembly, spin coating, doctor blade, printing, etc. In this embodiment, the dipping method may be preferably used.

Next, the substrate on which the ligands of the quantum dot particles have been exchanged is heat-treated (S30). The heat treatment may be performed at about 40 to 100 < 0 > C. Through the heat treatment, the electrical characteristics of the quantum dot thin film can be improved. During the heat treatment, the quantum dot particles adhere to each other, the electron binding energy of the quantum dot particles increases, and the volume of the thin film may decrease.

The substrate having the quantum dot thin film may be provided in various electronic devices using the quantum dot thin film, for example, a solar cell or the like.

Hereinafter, embodiments of the present invention will be described by way of specific examples and examples of quantum dots.

Synthetic example  1 indium Acenide  Seed particle

In a round flask, 0.29 g (1 mmol) of indium acetate (In (OAc) ₃ ) and 0.9 ml ( ₃ mmol) of oleic acid were mixed with 5 ml of octadecene and the reaction was conducted while being degassed under vacuum at 120 ° C for 1 hour, A precursor solution was prepared.

In another round flask, 0.14 g (0.5 mmol) of tris (trimethylsilyl) arnine, 1 ml of octadecine and 0.15 ml of oleylamine were mixed and mixed at 50 ° C for 1 hour to prepare an acetonide precursor solution.

After the temperature of the indium precursor solution was raised to 300 ° C, the precursor solution was rapidly introduced. Next, the temperature was lowered to 270 캜 and the reaction was carried out for 30 minutes to obtain seed particles.

Synthetic example  2 indium Acenide  Nanoclusters

In a round flask, 0.87 g ( ₃ mmol) of indium acetate (In (OAc) ₃ ) and 2.7 ml (9 mmol) of oleic acid were mixed with 15 ml of octadecene and the reaction was carried out while being degassed under vacuum at 120 ° C for 1 hour.

In another round flask, 0.42 g (1.5 mmol) of tris (trimethylsilyl) arsenide, 3 ml of octadecine and 0.45 ml of oleylamine were mixed and mixed at 50 ° C for 1 hour to prepare an acetonide precursor solution.

Next, the temperature of the indium precursor solution was lowered to room temperature, the above-mentioned precursor solution was added, and stirred at a constant rate for 10 minutes to obtain a nanocluster.

Synthetic example  3 indium Acenide Qdot

The solution containing the indium arsenide seed particles of Synthesis Example 1 was heated to 270 캜 or 300 캜 and a solution containing the indium arsenide nanocluster of Synthesis Example 2 was injected using a syringe (diameter 20 mm) : 0.005 to 0.05 mmol / min, on the basis of the equivalents of acetonitrile).

compare Synthetic example  1 indium Acenide  Seed particle

In a round flask, 0.29 g (1 mmol) of indium acetate (In (OAc) ₃ ) and 0.9 ml ( ₃ mmol) of oleic acid were mixed with 5 ml of octadecene and the reaction was conducted while being degassed under vacuum at 120 ° C for 1 hour, A precursor solution was prepared.

In another round flask, 0.14 g (0.5 mmol) of tris (trimethylsilyl) arsenide and 1 ml of octadecyne were mixed and mixed at room temperature to prepare an acetonide precursor solution.

After the temperature of the indium precursor solution was raised to 300 ° C, the precursor solution was rapidly introduced. Next, the temperature was lowered to 270 캜 and the reaction was carried out for 30 minutes to obtain seed particles.

compare Synthetic example  2 indium Acenide  Nanoclusters

In a round flask, 0.87 g ( ₃ mmol) of indium acetate (In (OAc) ₃ ) and 2.7 ml (9 mmol) of oleic acid were mixed with 15 ml of octadecene and the reaction was carried out while being degassed under vacuum at 120 ° C for 1 hour.

In another round flask, 0.42 g (1.5 mmol) of tris (trimethylsilyl) arsenide and 3 ml of octadecin were mixed at room temperature and mixed at 50 DEG C for 1 hour to prepare an acetonide precursor solution.

Next, the temperature of the indium precursor solution was lowered to room temperature, the above-mentioned precursor solution was added, and stirred at a constant rate for 10 minutes to obtain a nanocluster.

compare Synthetic example  3 indium Acenide Qdot

The solution containing the indium arsenide seed particles of Comparative Synthesis Example 1 was heated to 270 캜 or 300 캜 and a solution containing indium arsenide nanoclusters of Comparative Synthesis Example 2 was injected using a syringe (diameter 20 mm) Injection rate: 0.005 to 0.05 mmol / min, in terms of the equivalence of acetonide).

compare Synthetic example  4 indium Acenide Qdot

The solution containing the indium arsenide seed particles of Synthesis Example 1 was heated to 270 캜 or 300 캜 and a solution containing indium arsenide nanoclusters of Comparative Synthesis Example 2 was injected using a syringe (diameter 20 mm) Speed: 0.005 to 0.05 mmol / min, on the basis of the equivalents of acetonitrile).

compare Synthetic example  5 indium Acenide Qdot

The solution containing the indium arsenide seed particles of Comparative Synthesis Example 1 was heated to 270 캜 or 300 캜, and a solution containing the indium arsenide nanoclusters of Synthesis Example 2 was injected using a syringe (diameter 20 mm) Speed: 0.005 to 0.05 mmol / min, on the basis of the equivalents of acetonitrile).

4A is a graph showing absorption spectra of quantum dots in Synthesis Example 3, and Fig. 4B is a graph showing absorption spectra of quantum dots in Comparative Synthesis Example 3. Fig.

4A and 4B, the first excitation peak of the quantum dot ((TMSi) ₃ As) of Comparative Synthesis Example 3 appears at 970 nm and the half-width half-width (HWHM) thereof is 85 while the quantum dot (TMSi ) ₃ As-OLA) appears at 1018 nm, and its half-width half-width (HWHM) is 60, confirming that a narrower first excitation peak appears, which leads to improved size uniformity.

5 is a graph showing the normalized luminescence spectra of the quantum dots of Synthesis Example 3 and Comparative Synthesis Example 3. Fig.

5, it can be seen that the luminescence properties of the quantum dot ((TMSi) ₃ As-OLA) in Synthesis Example 3 were significantly improved compared to the quantum dots ((TMSi) ₃ As) of Comparative Synthesis Example 3.

6 is a graph showing the measurement of the impurity content and optical density of the quantum dots in Synthesis Example 3 and Comparative Synthesis Example 3. Fig.

6, Samples 1 to 8 were obtained by testing quantum dots ((TMSi) ₃ As) of Comparative Synthesis Example 3, and Samples 9 to 15 were obtained by testing quantum dots ((TMSi) ₃ As-OLA) of Synthesis Example 3 . Referring to FIG. 6, when quantum dots are prepared according to Synthesis Example 3, the By-product mass is low and the optical density (OD, 450 nm) is high.

FIG. 7A is a graph showing Fourier transform infrared (FTIR) measurement results of a thin film formed using quantum dots of Synthesis Example 3 before and after a ligand replacement process, and FIG. 7B is a graph showing the results of FTIR measurement of a thin film formed using quantum dots of Comparative Synthesis Example 3 (FTIR) measurement results before and after the ligand replacement process. A methanol solution containing 50 mg / ml of the quantum dots ((TMSi) ₃ As-OLA) of Synthesis Example 3 and the quantum dots ((TMSi) ₃ As) of Comparative Synthesis Example 3 was applied onto the glass substrate for the above- Spin coating, and 1% ethanedithiol (solvent is methanol).

7A and 7B, when the quantum dots ((TMSi) ₃ As-OLA) in Synthesis Example 3 are compared with the results of measurement before (LBL WITH EDT) before the ligand replacement process (before LBL) As shown in FIG.

Table 1 below shows optical densities (OD, 450 nm) and half-value half-widths (HWHM) of the quantum dots in Synthesis Example 3, Comparative Synthesis Example 4 and Comparative Synthesis Example 5.

Optical density (OD, 450 nm) Half half-width (HWHM, meV) Synthesis Example 3 1.846 60 Comparative Synthesis Example 4 1.058 87 Comparative Synthesis Example 5 0.894 80

Referring to Table 1, it can be seen that the effect of increasing the size uniformity and reducing the impurities is remarkably increased when the oleylamine is applied to both of the seed particles or the nanoclusters.

The following Table 2 shows the results of Table 2, except that in Synthesis Example 3 obtained using oleylamine, Synthesis Example 4 obtained using trioctylamine instead of oleylamine, Synthesis Example 5 obtained using octylamine instead of oleylamine, (OD, 450 nm) and half-value half-width (HWHM) of the quantum dots of Synthesis Example 6 obtained using dioctylamine.

Optical density (OD, 450 nm) Half half-width (HWHM, meV) Synthesis Example 3 1.846 60 Synthesis Example 4 1.870 60 Synthesis Example 5 1.450 68 Synthesis Example 6 1.775 52

Referring to Table 2, it can be seen that similar effects can be obtained when secondary amines such as dioctylamine or tertiary amines such as trioctylamine are used in addition to primary amines.

INDUSTRIAL APPLICABILITY The present invention can be used for various quantum dots, various electronic devices using solar cells, solar cells, display devices, light sources, and the like.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. You will understand.

Claims (15)

Reacting a Group III precursor solution comprising a Group III precursor and a solvent and a Group V precursor solution comprising a Group V precursor, a solvent and an amine to prepare a nanocluster comprising an amorphous phase comprising a Group III-V semiconductor compound ;
Preparing seed particles having the same semiconducting compound as the nanoclusters and having crystallinity; And
Reacting the seed particles with the nanoclusters to form quantum dots larger than the seed particles,
Wherein the mixing and reaction of the III-group precursor solution and the V-group precursor solution proceed at 40 < 0 > C or lower in the step of preparing the nanoclusters. The method of claim 1, wherein the semiconducting compound comprises indium arsenide. 3. The method of claim 2, wherein the semiconducting compound comprises a Group V precursor comprising tris (trimethylsilyl) acetamide. The method for producing a quantum dot according to claim 1, wherein the amine comprises an amine having an alkyl group having 6 or more carbon atoms. The method according to claim 4, wherein the amine comprises at least one selected from the group consisting of octylamine, hexylamine, oleylamine, dioctylamine, dihexylamine, trioctylamine and trihexylamine. ≪ / RTI > 5. The method of claim 4, wherein the solvent of the V-group precursor solution comprises a hydrocarbon. 6. The method of claim 5, wherein the volume ratio of the amine to the solvent in the V-group precursor solution is 30% to 70%. delete 2. The method of claim 1, wherein the seed particles are obtained by reacting a Group III precursor solution comprising a Group III precursor and a solvent and a Group V precursor solution comprising a Group V precursor, a solvent and an amine. Way. Reacting a Group III precursor solution comprising a Group III precursor and a solvent and a Group V precursor solution comprising a Group V precursor, a solvent and an amine to prepare a nanocluster comprising an amorphous phase comprising a Group III-V semiconductor compound ;
Preparing seed particles having the same semiconducting compound as the nanoclusters and having crystallinity;
Reacting the seed particles with the nanoclusters to form quantum dots larger than the seed particles;
Coating the quantum dot particles on a substrate to form a quantum dot thin film; And
Providing a ligand exchange composition comprising a ligand material in the quantum dot thin film to exchange ligands of the quantum dot particles,
Wherein the mixing and reaction of the III-group precursor solution and the V-group precursor solution proceed at 40 < 0 > C or lower in the step of preparing the nanoclusters. 11. The method of claim 10, wherein the ligand material comprises at least one selected from the group consisting of alkane thiol, hydrazine, and hydroxylamine. 11. The method of claim 10, further comprising the step of heat treating the quantum dot thin film after exchanging ligands of the quantum dot particles. The method according to claim 10, wherein the amine comprises at least one selected from the group consisting of octylamine, hexylamine, oleylamine, dioctylamine, dihexylamine, trioctylamine and trihexylamine. A method for producing a thin film. 14. The method of claim 13, wherein the volume ratio of the amine to the solvent in the V-group precursor solution is 30% to 70%. The method of claim 10, wherein the seed particles are obtained by reacting a Group III precursor solution comprising a Group III precursor and a solvent and a solution of a Group V precursor comprising a Group V precursor, a solvent and an amine. Gt;

Images