Method of manufacturing quantum dots and quantum dots

Abstract

The invention relates to a method for manufacturing a quantum dot and the quantum dot. The method of manufacturing a quantum dot includes: forming a core including silver (Ag) and indium (In); purifying the core with a surface treatment solution comprising gallium (Ga); and forming a shell surrounding (e.g., surrounding) the core by reacting a first precursor comprising gallium (Ga) with the core.

Description

Technical Field

[0001] This invention relates to a method for manufacturing quantum dots, quantum dots manufactured using this method, a display device comprising quantum dots, and an electronic device comprising quantum dots. More specifically, this invention relates to a method for manufacturing quantum dots having a red emission wavelength, quantum dots manufactured using this method, a display device comprising the same, and an electronic device comprising the same. Background Technology

[0002] Quantum dots are nanoscale semiconductor nanocrystals that exhibit quantum confinement effects. By controlling the size and composition of the nanocrystals, they can have different band gaps and thus emit light at one or more suitable emission wavelengths. A quantum dot may include: a core; a shell surrounding the core; and ligands formed on and chemically bonded to the surface of the shell.

[0003] A display device is a device that displays images to provide visual information to a user. In recent years, research has been conducted on the use of quantum dots in the manufacture of display devices. Summary of the Invention

[0004] One or more embodiments of this disclosure relate to methods for manufacturing quantum dots with improved or enhanced process economy.

[0005] One or more embodiments of this disclosure relate to quantum dots manufactured using the method, each having improved light-emitting properties, display devices including the same, and electronic devices including the same.

[0006] Further aspects of the implementation will be set forth in part in the description which follows, and in part will be obvious from the description or may be learned by practicing the embodiments presented in this disclosure.

[0007] A method for manufacturing quantum dots according to one or more embodiments may include: forming a core comprising silver (Ag) and indium (In); purifying the core with a surface treatment solution comprising gallium (Ga) (e.g., a Ga-containing compound); and forming a shell surrounding (e.g., encircling) the core by reacting a first precursor comprising gallium (Ga) (e.g., a Ga-containing precursor) with the core.

[0008] In one or more embodiments, the surface treatment solution may include at least one selected from GaI3 and Ga(acac)3.

[0009] In one or more embodiments, the purification of the nucleus can be carried out between the formation of the nucleus and the formation of the shell.

[0010] In one or more embodiments, after the nuclear purification, the peak emission wavelength of the nuclear photoluminescence (PL) spectrum may be about 600 nm or greater (e.g., greater than 600 nm).

[0011] In one or more embodiments, the formation of the core may include: adding a second precursor comprising silver (Ag) (e.g., an Ag-containing precursor) and a third precursor comprising indium (In) (e.g., an In-containing precursor) to the reaction vessel; and adding sulfur (S) to the reaction vessel.

[0012] In one or more embodiments, the second precursor may include at least one selected from AgF, AgCl, AgBr, AgI, Ag(NO3), Ag(OAc), Ag(acac), and Ag(DDTC).

[0013] In one or more embodiments, the third precursor may include at least one selected from InF3, InCl3, InBr3, InI3, In(NO3)3, In(OAc)3, In(acac)3 and In(DDTC)3.

[0014] In one or more embodiments, the addition of the second and third precursors may be carried out at a first temperature, and the addition of sulfur may be carried out at a second temperature for a first duration (e.g., during a first time period).

[0015] In one or more embodiments, the second temperature may be higher than the first temperature, and the second temperature may be greater than about 220°C.

[0016] In one or more embodiments, during the purification of the nucleus, the nucleus and the surface treatment solution may react at a third temperature below the second temperature.

[0017] In one or more embodiments, during the purification of the nucleus, the nucleus and the surface treatment solution may react for a second duration (e.g., during a second time period) that is longer than the first duration.

[0018] In one or more embodiments, the method may further include adding a ligand to the nucleus at a fourth temperature below a third temperature between the purification of the nucleus and the formation of the shell.

[0019] In one or more embodiments, sulfur may be added during shell formation to react with the core and the first precursor.

[0020] In one or more embodiments, the first precursor may include at least one selected from GaF3, GaCl3, GaBr3, GaI3, Ga(NO3)3, Ga(OAc)3, Ga(acac)3, and Ga(DDTC)3.

[0021] In one or more embodiments, the core may include AgInS2.

[0022] In one or more embodiments, the casing may include gallium (Ga).

[0023] A quantum dot according to one or more embodiments may include: a core comprising silver (Ag) and indium (In); and a shell surrounding (e.g., encircling) the core and comprising gallium (Ga) and sulfur (S), wherein the full width at half maximum (FWHM) of the emission wavelength of the quantum dot may be about 50 nm or less, and the peak emission wavelength of the PL spectrum of the quantum dot may be about 600 nm or greater.

[0024] In one or more embodiments, the average diameter of the core may be about 4.5 nm or greater and about 12 nm or smaller.

[0025] A display device according to one or more embodiments may include: a substrate including a light-emitting region and a non-light-emitting region adjacent to the light-emitting region; a color conversion pattern disposed in the light-emitting region and on the substrate; and a light-blocking pattern disposed in the non-light-emitting region, on the substrate, and adjacent to the color conversion pattern. The color conversion pattern includes quantum dots and a resin portion surrounding the quantum dots. The quantum dots have a full width at half maximum (FWHM) of about 50 nm or less and a peak emission wavelength of a photoluminescence (PL) spectrum greater than or equal to 600 nm. The quantum dots include: a core comprising silver (Ag) and indium (In); and a shell surrounding (e.g., encircling) the core and comprising gallium (Ga) and sulfur (S).

[0026] In one or more embodiments, the average diameter of the nucleus may be about 4.5 nm or greater and about 12 nm or smaller. Electronic devices according to one or more embodiments include the aforementioned quantum dots.

[0027] In a method for manufacturing quantum dots according to one or more embodiments of this disclosure, the nucleus is purified with a surface treatment solution after its formation, allowing confirmation of the peak emission wavelength of the nucleus's PL spectrum (e.g., whether it meets a set or predetermined emission wavelength) before shell formation. Accordingly, because the quality of the quantum dots can be evaluated (e.g., easily determined) during the quantum dot manufacturing process, the cost of the quantum dot manufacturing process can be reduced and the efficiency of the quantum dot manufacturing process can be improved. Furthermore, quantum dots with substantially uniform dimensions can be manufactured more easily.

[0028] In quantum dots according to one or more embodiments of the present disclosure, the average diameter of the nucleus may be about 4.5 nm or larger, and the full width at half maximum (FWHM) of the emission wavelength of the quantum dot may be about 50 nm or smaller. Accordingly, because the quantum dot has a bulk (e.g., large) sized nucleus and a narrow FWHM of the emission wavelength, the emission efficiency of the quantum dot can be improved.

[0029] In a display device according to one or more embodiments of the present disclosure, the average diameter of the nucleus may be about 4.5 nm or greater, and the full width at half maximum (FWHM) of the emission wavelength of the quantum dot may be about 50 nm or less. Accordingly, the display quality of the display device can be improved. Attached Figure Description

[0030] The illustrative and non-limiting embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.

[0031] Figure 1 This is a schematic diagram of a quantum dot according to one or more embodiments of the present disclosure.

[0032] Figure 2 To explain manufacturing Figure 1 The flowchart of the quantum dot method.

[0033] Figure 3 To explain Figure 2 The flowchart of the formation of the nucleus.

[0034] Figure 4 For the purpose of explanation when performing Figure 2 A schematic diagram of temperature changes during the manufacturing process of quantum dots.

[0035] Figure 5 , Figure 6 , Figure 7 and Figure 8 Each graph represents the effect of PL intensity versus wavelength on the explanation of the effects of quantum dots and the methods used to manufacture them.

[0036] Figure 9 Images of Comparative Examples 1 to 4 are shown.

[0037] Figure 10 Images of Examples 1 and 2 are shown.

[0038] Figure 11 For including Figure 1 A plan view of a quantum dot display device.

[0039] Figure 12 For along Figure 11 The cross-sectional view taken from line I-I'. Detailed Implementation

[0040] In the following description, the display device according to the embodiment will be described in more detail with reference to the accompanying drawings. The same reference numerals are used for the same components in the drawings, and repeated descriptions of the same components will not be provided.

[0041] Figure 1 This is a schematic diagram of a quantum dot according to one or more embodiments of the present disclosure.

[0042] refer to Figure 1A quantum dot (QD) according to one or more embodiments of this disclosure may include a core 100, a shell 200, and a ligand 300. The core 100 may include AgInS2, which is a group I-III-VI semiconductor compound (i.e., a group I-III-VI semiconductor compound). The shell 200 may surround the core 100 (e.g., encircle the core 100). The ligand 300 may be bonded to the surface of the shell 200. In one or more embodiments, the quantum dot (QD) may be a quantum dot having a red emission wavelength (e.g., emitting red light).

[0043] The casing 200 may include gallium (Ga). For example, the casing 200 may be GaS, which includes gallium (Ga) and sulfur (S). x Shell. However, the composition of the shell 200 according to one or more embodiments of this disclosure is not limited thereto. The shell 200 of the quantum dot QD can serve as a protective layer to maintain semiconductor properties by preventing or reducing chemical modification of the core 100, and / or as a charging layer to impart electrophoretic properties to the quantum dot QD. The shell 200 can be a single layer or multiple layers. The interface between the core 100 and the shell 200 can have a concentration gradient in which the concentration of elements present in the shell 200 decreases toward the center of the core 100.

[0044] Ligand 300 improves the physical and chemical stability of quantum dots (QDs) so that adjacent QDs do not aggregate (e.g., clump together) during QD fabrication. Ligand 300 may comprise organic materials. For example, organic materials may include trioctylphosphine (TOP), trioctylphosphine oxide (TOPO), oleic acid, oleylamine, octylamine, trioctylamine, hexadecylamine, octyl mercaptan, dodecyl mercaptan, hexylphosphonic acid (HPA), tetradecylphosphonic acid (TDPA), and / or octylphosphonic acid (OPA), etc. These materials may be used alone or in combination with each other.

[0045] In one or more embodiments, the average diameter D2 of the core 100 may be about 4.5 nm or greater and about 12 nm or less. In one or more embodiments, the average diameter D2 of the core 100 may be about 6 nm or greater and about 12 nm or less.

[0046] In one or more embodiments, the average diameter D1 of the core 100 and shell 200 (together) may be about 6 nm or greater and about 20 nm or less. In one or more embodiments, the average diameter D1 of the core 100 and shell 200 may be about 8 nm or greater and about 15 nm or less.

[0047] In one or more embodiments, the emission wavelength of the PL spectrum (photoluminescence spectrum) of the quantum dot QD may be about 600 nm or greater. In one or more embodiments, the emission wavelength of the PL spectrum of the quantum dot QD may be about 600 nm or greater and about 640 nm or less.

[0048] In one or more embodiments, the full width at half maximum (FWHM) of the emission wavelength of the quantum dot QD may be about 50 nm or less. In one or more embodiments, the full width at half maximum (FWHM) of the emission wavelength of the quantum dot QD may be about 40 nm or greater and about 45 nm or less.

[0049] As described above, in a quantum dot QD according to one or more embodiments of the present disclosure, the average diameter D2 of the core 100 may be about 4.5 nm or greater, and the full width at half maximum (FWHM) of the emission wavelength of the quantum dot QD may be about 50 nm or less. For example, because the quantum dot QD has a bulk-sized core 100 (e.g., with a diameter of 4.5 nm or greater) and a narrow full width at half maximum (FWHM) of the emission wavelength, the emission efficiency of the quantum dot QD can be improved.

[0050] Figure 2 To explain manufacturing Figure 1 The flowchart of the quantum dot method. Figure 3 To explain Figure 2 The flowchart of the formation of the nucleus. Figure 4 For the purpose of explanation when performing Figure 2 A schematic diagram of temperature changes during the manufacturing process of quantum dots.

[0051] refer to Figure 2 , Figure 3 and Figure 4 A method for manufacturing quantum dots according to one or more embodiments of the present disclosure may include: forming a core comprising AgInS2 (e.g., Figure 1 The nucleus 100 is purified (step S10); the nucleus is purified with a surface treatment solution (step S20); a ligand is added to the nucleus (step S30); a GaS-containing nucleus is formed. x The shell (e.g., Figure 1 The formation of the core (step S10) may include: adding a first precursor, a second precursor, and a solvent to the reaction vessel (step S110); and adding sulfur (S) to the reaction vessel (step S120). In this disclosure, the first precursor and the second precursor may also be referred to as a second precursor comprising silver (Ag) and a third precursor comprising indium (In), respectively. For example, the first precursor may be referred to as a second precursor comprising (containing) silver (Ag), and the second precursor may be referred to as a third precursor comprising (containing) indium (In).

[0052] During nucleus formation (step S10), an AgInS2 nucleus comprising silver (Ag) and indium (In) can be formed. When the first precursor, the second precursor, and the solvent are added to the reaction vessel (step S110), the reaction vessel provides space for the nucleosynthesis reaction. For example, the reaction vessel can be a synthesis flask. In one or more embodiments, the volume of the reaction vessel can be about 50 mL. However, the type (type) and volume of the reaction vessel according to one or more embodiments of this disclosure are not limited to this, and one or more suitable types (types) of vessels or volumes may be used.

[0053] The first precursor may include silver (Ag) (e.g., an Ag-containing precursor). In one or more embodiments, the first precursor may include AgF, AgCl, AgBr, AgI, Ag(NO3), Ag(OAc), Ag(acac), and / or Ag(DDTC), etc. These materials may be used alone or in combination with each other. The second precursor may include indium (In) (e.g., an In-containing precursor). In one or more embodiments, the second precursor may include InF3, InCl3, InBr3, InI3, In(NO3)3, In(OAc)3, In(acac)3, and / or In(DDTC)3, etc. These materials may be used alone or in combination with each other. The solvent may include ODE (octadecene), OLA (oleylamine), and / or OA (oleic acid), etc. These solvents may be used alone or in combination with each other. Throughout this disclosure, in compounds containing OAc, acac, and / or DDTC, OAc refers to an acetic acid group, acac refers to an acetylacetonate group, and DDTC refers to a diethyldithiocarbamate group.

[0054] In one or more embodiments, the addition of a first precursor, a second precursor, and a solvent to the reaction vessel (step S110) can be carried out at a first temperature. For example, the first precursor, the second precursor, and the solvent can be added to the reaction vessel and reacted at the first temperature. In one or more embodiments, the first temperature can be from about 100°C to about 150°C. In one or more embodiments, the first temperature can be about 120°C.

[0055] When adding sulfur (S) to the reaction vessel (step S120), sulfur (S) may be added to a solution formed by the reaction of a first precursor, a second precursor, and a solvent. For example, an S-OLA solution in which sulfur (S) is dissolved in OLA and a thiolate may be introduced into the reaction vessel. In one or more embodiments, the addition of sulfur (S) to the reaction vessel (step S120) may be carried out at a second temperature. The second temperature may be higher than the first temperature. For example, the second temperature may be about 220°C or higher. In one or more embodiments, the second temperature may be about 240°C or higher to about 280°C or lower. For example, the second temperature may be about 260°C.

[0056] In one or more embodiments, the addition of sulfur (S) to the reaction vessel (step S120) may be carried out for a first time t1 (e.g., within a first duration). For example, the first time t1 may be about 2 minutes or more and about 3 minutes or less. In one or more embodiments, the first time t1 may be about 2 minutes and 30 seconds.

[0057] After adding sulfur (S) to the reaction vessel (step S120) for a first time t1, the nucleus can be purified with a surface treatment solution (step S20). In one or more embodiments, the purification of the nucleus (step S20) can be carried out at a third temperature. For example, the third temperature can be about 200°C.

[0058] During the purification of the nucleus with the surface treatment solution (step S20), the surface treatment solution may be added to the reaction vessel after the third temperature is reached. In one or more embodiments, the surface treatment solution may include gallium (Ga). For example, the surface treatment solution may include GaI3 and / or Ga(acac)3, etc. These materials may be used alone or in combination with each other.

[0059] In one or more embodiments, the purification of the nucleus with the surface treatment solution (step S20) can be performed at a second time t2 (e.g., within a second duration). In one or more embodiments, the second time t2 can be greater than the first time t1. For example, the second time t2 can be about 8 minutes or more. In one or more embodiments, the second time t2 can be about 10 minutes. The addition of a ligand to the nucleus (step S30) can be performed between the purification of the nucleus with the surface treatment solution (step S20) and the formation of the shell (step S40). In one or more embodiments, the addition of a ligand to the nucleus (step S30) can be performed at a fourth temperature. In one or more embodiments, the fourth temperature can be lower than a third temperature. For example, the fourth temperature can be lower than about 200°C. In one or more embodiments, the fourth temperature can be about 180°C. In one or more embodiments, the ligand can include TOP. For example, when adding a ligand to the nucleus (step S30), a TOP solution can be injected into the reaction vessel. In one or more embodiments, the addition of a ligand to the nucleus (step S30) can be performed for about 20 minutes. For example, the TOP solution can be injected into the reaction vessel at approximately 180°C and reacted for approximately 20 minutes.

[0060] After adding ligands to the core (step S30), the temperature can be lowered to below a fourth temperature before the shell formation step (e.g., action or task) (step S40). For example, after adding ligands to the core (step S30), the temperature can be lowered to room temperature before the shell formation (step S40), and the process associated with core formation (e.g., generation) can be terminated.

[0061] During shell formation (step S40), the third precursor and the core can react to form the shell. For example, during shell formation (step S40), a purified core, a third precursor, sulfur (S), and a solvent can be added to the reaction vessel. The purified core is formed by forming the core in the reaction vessel (step S10), purifying the core with a surface treatment solution (step S20), and adding a ligand to the core (step S30). In this disclosure, the third precursor may be referred to as a first precursor comprising gallium (Ga).

[0062] In one or more embodiments, the third precursor may include GaF3, GaCl3, GaBr3, GaI3, Ga(NO3)3, Ga(OAc)3, Ga(acac)3, and / or Ga(DDTC)3, etc. During shell formation (step S40), the third precursor may be added to the reaction vessel in a solution state dissolved in a solvent (such as toluene). During shell formation (step S40), sulfur (S) may be added to the reaction vessel in an S-OLA state. During shell formation (step S40), a nitrogen substitution reaction may be carried out in the reaction vessel.

[0063] When adding a ligand to the shell (step S50), the ligand may include TOP. For example, when adding a ligand to the shell (step S50), a ZnCl2 solution dissolved in TOP and dodecyl mercaptan may be added. For example, when adding a ligand to the shell (step S50), after adding the ZnCl2 solution dissolved in TOP and dodecyl mercaptan, the reaction may be carried out in a reaction vessel at about 200°C for about 20 minutes.

[0064] However, the execution temperatures of each of the following steps according to one or more embodiments of this disclosure—nucleus formation (step S10), nucleus purification with a surface treatment solution (step S20), addition of ligands to the nucleus (step S30), shell formation (step S40), and addition of ligands to the shell (step S50)—are provided as examples, and this disclosure is not limited thereto. The temperature for each step may have a variety of suitable temperatures (e.g., may be appropriately adjusted).

[0065] As described above, in the method for manufacturing quantum dots according to one or more embodiments of this disclosure, by purifying the nucleus with a surface treatment solution (step S20) after nucleus formation (step S10), the peak emission wavelength of the PL spectrum of the nucleus can be confirmed before shell formation. Accordingly, because it is easier to determine whether the quantum dots are well formed (e.g., meeting the desired peak emission wavelength of the PL spectrum) during the quantum dot manufacturing process, the cost of the quantum dot manufacturing process can be reduced and the efficiency of the quantum dot manufacturing process can be improved. In addition, quantum dots with substantially uniform dimensions can be easily manufactured.

[0066] Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10 A graph or image used to explain the effects of quantum dots and methods for manufacturing quantum dots.

[0067] For example, Figure 5 The graph shows the kernel values ​​for the comparative example, and Figure 7 This is a graph showing the entire quantum dot, including the core and shell, for the comparative example.

[0068] For example, Figure 6 The graph shows the kernel of the embodiment, and Figure 8 This is a graph showing the entire quantum dot, including the core and shell, in relation to the embodiment.

[0069] For example, Figure 9 and 10 TEM images used to explain the effects of quantum dots and methods for manufacturing them.

[0070] The effects of this disclosure will be described below with reference to embodiments and comparative examples.

[0071] Manufacturing Example 1: Formation of AgInS2 cores

[0072] 0.4 mmol of AgI, 0.9 mmol of InI3, 2.5 mL of ODE, 2.5 mL of OA, and 5 mL of OLA were placed in a 50 mL synthesis flask and heated to 120 °C for nitrogen substitution reaction. Then, 1.6 mL of S-OLA solution (1 M) and 1.6 mL of 1-octylthiol (Sigma-Aldrich, 98.5 wt% (content determined)) stock solution were added to the synthesis flask, and the flask was heated to 200 °C and reacted for 2 min 30 sec. Subsequently, the temperature was lowered to 180 °C, 4 mL of TOP stock solution was added to the synthesis flask, the reaction was carried out for 20 min, and then the temperature was lowered to room temperature to form the AgInS2 core.

[0073] Manufacturing Example 2: Formation of AgInS2 cores and treatment of Ga solution

[0074] 0.4 mmol of AgI, 0.9 mmol of InI3, 2.5 mL of ODE, 2.5 mL of OA, and 5 mL of OLA were placed in a 50 mL synthesis flask and heated to 120 °C for nitrogen substitution reaction. Then, 1.6 mL of S-OLA solution (1 M) and 1.6 mL of 1-octylthiol (Sigma-Aldrich, 98.5 wt% (as determined)) stock solution were added to the synthesis flask, and the flask was heated to 260 °C and reacted for 2 min 30 sec. Subsequently, the temperature was lowered to 200 °C, and 1 mL of Ga-OLA solution (1 M) containing Ga(acac)3 was added to the synthesis flask, and the reaction was carried out for 10 min. Afterward, the temperature was lowered to 180 °C, 4 mL of TOP solution was added to the synthesis flask, and the reaction was carried out for 20 min. The temperature was then lowered to room temperature to form the AgInS2 core.

[0075] Comparative Example 1

[0076] Comparative Example 1 is AgInS2 / GaS manufactured as follows x Quantum dots: AgInS2 cores prepared according to manufacturing example 1, 8 mL of OLA, 2.3 mmol of GaCl3 solution dissolved in 1 mL of toluene, and 1.6 mL of S-OLA solution (1 M) were placed in a 50 mL synthesis flask, heated to 200 °C, and 0.5 mL of ZnCl2-TOP solution (0.63 M) and 0.5 mL of 1-dodecyl mercaptan (Sigma-Aldrich, 98.5 wt% (content determination)) stock solution were added to the synthesis flask and the reaction was carried out for 20 minutes.

[0077] Comparative Example 2

[0078] Comparative Example 2 is AgInS2 / GaS manufactured using essentially the same manufacturing process as Comparative Example 1. x The difference with quantum dots is that, during the manufacturing process of Example 1, 1.6 mL of S-OLA solution (1M) and 1.6 mL of 1-octylthiol (Sigma-Aldrich, 98.5 wt% (content determination)) stock solution were placed in a synthesis flask and heated to 240 °C instead of 200 °C.

[0079] Comparative Example 3

[0080] Comparative Example 3 is AgInS2 / GaS manufactured using essentially the same manufacturing process as Comparative Example 1. xThe difference with quantum dots is that, during the manufacturing process of Example 1, 1.6 mL of S-OLA solution (1M) and 1.6 mL of 1-octylthiol (Sigma-Aldrich, 98.5 wt% (content determination)) stock solution were placed in a synthesis flask and heated to 260 °C instead of 200 °C.

[0081] Comparative Example 4

[0082] Comparative Example 4 is AgInS2 / GaS manufactured using essentially the same manufacturing process as Comparative Example 1. x The difference with quantum dots is that, during the manufacturing process of Example 1, 1.6 mL of S-OLA solution (1M) and 1.6 mL of 1-octylthiol (Sigma-Aldrich, 98.5 wt% (content determination)) stock solution were placed in a synthesis flask and heated to 270 °C instead of 200 °C.

[0083] refer to Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10 Example 1 is an AgInS2 / GaS manufactured as follows. x Quantum dots: AgInS2 cores prepared according to Manufacturing Example 2, 8 mL of OLA, a solution of 2.3 mmol of GaCl3 dissolved in 1 mL of toluene, and 1.6 mL of S-OLA (1 M) were placed in a 50 mL synthesis flask, heated to 200 °C, and 0.5 mL of ZnCl2-TOP (0.63 M) and 0.5 mL of a stock solution of 1-dodecyl mercaptan (Sigma-Aldrich, 98.5 wt% (content determination)) were added to the synthesis flask, and the reaction was carried out for 20 minutes. Example 2 describes quantum dots prepared using essentially the same process as in Example 1, except that 1 mL of Ga-OLA (0.5 M) containing GaI3 instead of Ga(acac)3 was added to the synthesis flask during the manufacturing process of Example 2.

[0084] According to Figure 5 and Figure 6 The PL spectra measured during the nucleation process for each of the comparative examples and embodiments illustrated herein, with the peak emission wavelengths of the PL spectra of the nuclei shown in Table 1.

[0085] Table 1

[0086] Example type Peak emission wavelength (nm) of the nuclear PL spectrum Comparative Example 1 - Comparative Example 2 - Comparative Example 3 - Comparative Example 4 - Example 1 623 Example 2 627

[0087] Referring to Table 1 above, in Examples 1 and 2, the peak emission wavelength of the PL spectrum of the nucleus was 600 nm or greater, wherein the nucleus was surface-treated with a gallium solution of Ga-OLA at 200 °C. Furthermore, in Comparative Examples 1, 2, 3, and 4, where the nucleus was not surface-treated, the peak emission wavelength of the PL spectrum of the nucleus could not be specified (e.g., it was difficult to determine precisely). Accordingly, in performing the nucleus formation process (e.g., Figure 2 The process of purifying the nucleus with gallium solution in the formation of the nucleus (step S10), purification of the nucleus with a surface treatment solution (step S20), and addition of a ligand to the nucleus (step S30) (e.g., the process of purifying the nucleus with gallium solution) Figure 2 In the case of purifying the nucleus with a surface treatment solution (step S20), the peak emission wavelength of the nucleus's PL spectrum can be confirmed even during the nucleus formation process before shell formation. Accordingly, since it is easy to determine whether the nucleus is well formed before shell formation, the cost of the quantum dot manufacturing process can be reduced and the efficiency of the quantum dot manufacturing process can be improved. In addition, quantum dots with substantially uniform dimensions can be easily manufactured.

[0088] exist Figure 7 and Figure 8 The peak emission wavelength and full width at half maximum (FWHM) of the PL spectra of each quantum dot in the comparative examples and embodiments illustrated herein are shown in Table 2.

[0089] Table 2

[0090]

[0091] Referring to Table 2 above, the quantum dots with core / shell structures in Comparative Examples 1, 2, 3, 4, Example 1, and 2 have a full width at half maximum (FWHM) of 50 nm or less in their emission wavelengths. Furthermore, the quantum dots in Comparative Examples 3, 1, and 2, which were reacted at 260°C with S-OLA solution and 1-octylthiol solution added during the nucleation process, exhibit similar peak emission wavelengths, FWHMs, and fluorescence yields in their PL spectra. Correspondingly, in the nucleation process, the characteristics of quantum dots fabricated by surface treatment of the core with gallium solution are not significantly different from those fabricated without surface treatment of the core with gallium solution.

[0092] The fluorescence yield was obtained by irradiating the quantum dots of the examples and comparative examples with excitation light, measuring the emitted fluorescence intensity, and calculating the ratio of the number of emitted photons to the number of absorbed photons.

[0093] Table 1 is about the nucleus, and Table 2 is about the entire quantum dot including the nucleus and shell.

[0094] exist Figure 9 and Figure 10The average diameter of the nucleus for each of the comparative examples and embodiments illustrated herein is shown in Table 3.

[0095] Table 3

[0096] Example type Average diameter of the nucleus (nm) Comparative Example 1 4.1 Comparative Example 2 5 Comparative Example 3 6.1 Comparative Example 4 10 Example 1 6.1 Example 2 6.2

[0097] Referring to Table 3 above, the addition of S-OLA solution and 1-octylthiol solution and the reaction temperature (e.g., when performing...) Figure 2 The higher the second temperature at which sulfur (S) is added to the reaction vessel (step S120), the larger the average diameter of the nucleus. In Comparative Examples 2 to 4, and Examples 1 and 2, the desired or required second temperature for forming a bulk nucleus with an average diameter of 4.5 nm or greater was confirmed because S-OLA solution and 1-octylthiol solution were added and reacted at 240 °C or higher.

[0098] Figure 11 For including Figure 1 A plan view of a quantum dot display device. Figure 12 For along Figure 11 The cross-sectional view taken from line I-I'.

[0099] refer to Figure 11 and Figure 12 The described display device DD may include Figure 1 Quantum dot quantum dots (QDs). For example, color conversion patterns (CVLs) may include quantum dot QDs. In the following text, omissions or simplifications may be made in conjunction with references. Figure 1 Any content (e.g., description) that overlaps with the content of the quantum dot QD described.

[0100] refer to Figure 1 , Figure 11 and Figure 12 A display device DD according to one or more embodiments of the present disclosure may include a display area DA and a peripheral area PA. The display area DA may include a light-emitting area LA and a non-light-emitting area NLA adjacent to the light-emitting area LA.

[0101] The display area DA can be an area that displays an image by generating light or controlling the transmittance of light provided from an external light source. At least one light-emitting pixel PX can be arranged in the display area DA.

[0102] In this disclosure, the plane may be defined by a first direction DR1 and a second direction DR2 intersecting the first direction DR1. For example, the first direction DR1 and the second direction DR2 may be orthogonal to each other (e.g., perpendicular). In addition, a third direction DR3 may be orthogonal to (e.g., perpendicular to) the plane.

[0103] Multiple pixels (PXs) can be arranged within the display area DA. For example, the pixels (PXs) can be arranged in a matrix within the display area DA along a first direction DR1 and a second direction DR2. The multiple pixels (PXs) can emit light of different colors. For example, the multiple pixels (PXs) may include a first pixel for emitting a first light, a second pixel for emitting a second light, and a third pixel for emitting a third light. For example, the first light may be green, the second light may be red, and the third light may be blue. However, the color of the light emitted by the pixels (PXs) according to one or more embodiments of this disclosure is not limited to this, and light having one or more suitable colors (such as magenta, cyan, and / or yellow) can be emitted.

[0104] The peripheral region PA may surround (e.g., encircle) at least a portion of the display region DA. For example, in a plan view, the peripheral region PA may completely surround (e.g., encircle) the display region DA. The peripheral region PA may be defined as a region that does not emit light and does not produce an image. A driver for driving the pixel PX may be arranged in the peripheral region PA. The driver may provide signals and / or voltages to the pixel PX.

[0105] The display device DD may include a substrate SUB, a bottom metal layer BML, a buffer layer BFL, an active layer ACT, a gate insulating layer GIL, a gate electrode GE, an interlayer insulating layer ILD, a source electrode SE, a drain electrode DE, a via insulating layer VIA, a pixel electrode PE, a pixel defining layer PDL, a light-emitting layer EML, a common electrode CE, a package layer TFE, a color conversion pattern CVL, a barrier layer BK, a refractive layer LR, a color filter CF, a light-blocking pattern BM, and a planarization layer OC. The pixel electrode PE, the light-emitting layer EML, and the common electrode CE may together define a light-emitting element LED. The active layer ACT, the gate electrode GE, the source electrode SE, and the drain electrode DE may together define a transistor.

[0106] The substrate SUB can be used as a substrate for the pixel PX. The substrate SUB may comprise a transparent or opaque material. In one or more embodiments, examples of materials used as the substrate SUB include glass, quartz, and / or plastic. These materials may be used alone or in combination with each other.

[0107] The bottom metal layer (BML) may be disposed on the substrate (SUB). The bottom metal layer (BML) prevents or substantially prevents the introduction of impurities into the substrate (SUB) or prevents or substantially prevents static electricity from occurring in the active layer (ACT). The bottom metal layer (BML) may include a conductive material.

[0108] A buffer layer (BFL) may be disposed on the bottom metal layer (BML). The buffer layer (BFL) prevents or substantially prevents the diffusion of metal atoms or impurities from the substrate (SUB) to the active layer (ACT). Additionally, the buffer layer (BFL) controls the rate of heat delivery during the crystallization process used to form the active layer. The buffer layer (BFL) may include an insulating material.

[0109] The active layer ACT can be disposed on the buffer layer BFL. The active layer ACT may include a source region connected to the source electrode SE, a drain region connected to the drain electrode DE, and a channel region disposed between the source region and the drain region. The active layer ACT may include polysilicon and / or oxide semiconductors, etc.

[0110] A gate insulating layer (GIL) may be disposed on the active layer ACT. The gate insulating layer (GIL) may comprise an inorganic insulating material. In one or more embodiments, the gate insulating layer (GIL) may cover the upper surface of the active layer ACT along the contour of the active layer ACT. However, the gate insulating layer (GIL) according to one or more embodiments of the present disclosure is not limited thereto, and the gate insulating layer (GIL) may not create steps (e.g., unevenness) around the active layer ACT, and may have a substantially flat upper surface.

[0111] The gate electrode GE may be disposed on the gate insulating layer GIL. In a plan view, the gate electrode GE may overlap with the active layer ACT. For example, the channel region may be defined as a portion of the active layer ACT that overlaps with the gate electrode GE. The gate electrode GE may include a conductive material.

[0112] An interlayer insulating layer (ILD) may be disposed on the gate electrode GE. The interlayer insulating layer (ILD) may comprise an inorganic insulating material. In one or more embodiments, the interlayer insulating layer (ILD) may cover the upper surface of the gate electrode GE along the contour of the gate electrode GE. However, the interlayer insulating layer (ILD) according to one or more embodiments of the present disclosure is not limited thereto, and the interlayer insulating layer (ILD) may have a substantially flat upper surface without creating steps around the gate electrode GE.

[0113] The source electrode SE and drain electrode DE can be disposed on the interlayer insulating layer ILD. The source electrode SE and drain electrode DE can contact the source region and drain region respectively through openings in the third-direction DR3 that penetrate the interlayer insulating layer ILD and the gate insulating layer GIL. Each of the source electrode SE and drain electrode DE may include a conductive material.

[0114] The via insulating layer VIA can be disposed on the source electrode SE and the drain electrode DE. The via insulating layer VIA may include an organic insulating material. The via insulating layer VIA may have a substantially flat upper surface.

[0115] The pixel electrode PE may be disposed on the via insulating layer VIA. In one or more embodiments, the pixel electrode PE may contact the source electrode SE through an opening in the via insulating layer VIA in the third-direction DR3. However, according to one or more embodiments of this disclosure, the pixel electrode PE may not be limited to this, and the pixel electrode PE may contact the drain electrode DE through the opening. The pixel electrode PE may include a conductive material.

[0116] The pixel defining layer (PDL) may be disposed on the via insulating layer (VIA). The PDL may partially cover the pixel electrode (PE). For example, the PDL may define an opening that exposes the center of the pixel electrode (PE), and the PDL may cover the edge of the pixel electrode (PE).

[0117] The emissive layer EML can be disposed on the pixel electrode PE. The emissive layer EML can be disposed on the pixel electrode PE exposed by an opening in the pixel defining layer PDL. The emissive layer EML may include organic light-emitting materials and / or quantum dots, etc. The emissive layer EML can be disposed in the emissive region LA.

[0118] The common electrode CE can be disposed on the emitter layer EML and the pixel defining layer PDL. The common electrode CE may include a conductive material. The common electrode CE can be disposed across the emitting region LA and the non-emitting region NLA.

[0119] The encapsulation layer TFE can be disposed on the common electrode CE. The encapsulation layer TFE can cover the light-emitting element LED. In one or more embodiments, the encapsulation layer TFE may include at least one organic layer and at least one inorganic layer. However, the encapsulation layer TFE according to one or more embodiments of the present disclosure is not limited thereto, and the encapsulation layer TFE may be a substrate including glass or the like.

[0120] A color conversion pattern (CVL) can be arranged on the encapsulation layer TFE. The CVL can overlap with the emission layer EML. The CVL can be arranged within the light-emitting region LA. The CVL can include a pattern having a red emission wavelength (e.g., emitting red light). Figure 1 The quantum dot (QD) is used. A color conversion pattern (CVL) can convert the wavelength of light emitted from an emitting layer (EML). For example, if light emitted from an emitting layer (EML) overlapping with a color conversion pattern (CVL) that includes a quantum dot (QD) having a red emission wavelength passes through the color conversion pattern (CVL), red light can be emitted. However, according to one or more embodiments of this disclosure, the color of light passing through the color conversion pattern (CVL) is not limited to this, and another color conversion pattern (CVL) adjacent to the color conversion pattern (CVL) including a quantum dot (QD) having a red emission wavelength can transmit light of colors other than red.

[0121] In one or more embodiments, the color conversion pattern (CVL) may include fluorescent materials, scattering materials, and / or quantum dots (QDs). The CVL may include a resin portion surrounding (e.g., encircling) the quantum dots (QDs). The resin portion may include polymeric resins, etc.

[0122] A barrier layer BK can be disposed on the encapsulation layer TFE. The barrier layer BK can be formed of a light-blocking material and can block light emitted from below. In addition, an opening that exposes the encapsulation layer TFE can be formed in the barrier layer BK.

[0123] A refractive layer LR can be disposed on a color conversion pattern CVL. The refractive layer LR can have a set or predetermined refractive index that differs from that of adjacent layers (e.g., from that of the color conversion pattern CVL). Accordingly, the light efficiency of the display device can be improved. However, the refractive layer LR according to one or more embodiments of this disclosure is not limited thereto, and the refractive layer LR can be disposed below the color conversion pattern CVL. Furthermore, the refractive layer LR can have a single-layer structure or a multi-layer structure.

[0124] A color filter CF may be disposed on a refractive layer LR. The color filter CF may overlap with an emissive layer EML and a color conversion pattern CVL. The color filter CF may transmit light of a wavelength corresponding to the light emitted from the emissive layer EML that overlaps with it. For example, a color filter CF overlapping with a color conversion pattern CVL including quantum dots QD having a red emission wavelength may transmit red light. However, the color filter CF according to one or more embodiments of this disclosure may not be limited thereto, and a color filter CF not overlapping with a quantum dot QD having a red emission wavelength may transmit light of colors other than red.

[0125] A light-blocking pattern BM can be arranged on the refractive layer LR. The light-blocking pattern BM can be formed of a light-blocking material and can block light emitted from below. In addition, an opening can be formed in the light-blocking pattern BM to expose the refractive layer LR. The light-blocking pattern BM can also be arranged in the non-emissive region NLA.

[0126] The planarization layer OC can be disposed on the color filter CF. The planarization layer OC can be formed of organic material and can provide a substantially flat upper surface.

[0127] Although the quantum dot QD according to one or more embodiments of the present disclosure is interpreted as being included in a color conversion pattern (CVL), the quantum dot QD according to one or more embodiments of the present disclosure is not limited thereto, and the quantum dot QD may be included in an emissive layer (EML).

[0128] As described above, the average diameter of the core 100 of the quantum dot QD according to one or more embodiments of the present disclosure may be about 4.5 nm or larger (e.g., greater than 4.5 nm) and about 12 nm or smaller, and the quantum dot QD may have a full width at half maximum (FWHM) of the emission wavelength of about 50 nm or smaller. Accordingly, because the quantum dot QD has a bulk-sized core 100 and a narrow FWHM of the emission wavelength, the display quality of the display device DD can be improved.

[0129] The quantum dot manufacturing method, quantum dots, and display device according to one or more embodiments can be applied to electronic devices, such as computers, laptops, mobile phones, smartphones, smart tablets, PMPs, PDAs, MP3 players, televisions, monitors, tablet computers, and / or electric vehicles, etc.

[0130] Unless otherwise specifically defined in this description, particle size may refer to the average particle size (average diameter). Additionally, particle size indicates the average particle size (D) that constitutes approximately 50% by volume of the cumulative volume in the particle size distribution. 50 Average particle size (D) 50 The particle size distribution (D) can be measured by appropriate methods, such as by a particle size analyzer, transmission electron microscopy (TEM) images, or scanning electron microscopy (SEM) images. In one or more embodiments, a dynamic light scattering measurement device is used for data analysis, counting the number of particles for each particle size range, and then calculating the average particle size (D). 50 In contrast, laser scattering methods can be used to measure the average particle size (D). 50 In the laser scattering method, target particles are distributed in a dispersion solvent and introduced into a laser scattering particle size analyzer (e.g., the MT3000, commercially available from Microtrac, Inc.). The particles are irradiated with 28 kHz ultrasound at a power of 60 W, and the average particle size (D) is then calculated using a 50% standard of particle size distribution within this analyzer. 50 ).

[0131] As used herein, the terms “use,” “using,” and “used” are to be regarded as synonyms with the terms “utilize,” “utilizing,” and “utilized,” respectively. As used herein, expressions such as “at least one of…,” “one of…,” and “selected from…” modify the entire list of elements when placed before or after a list of elements, without modifying any individual element of the list. For example, “selected from at least one of a, b, and c” and “at least one of a, b, and / or c” can indicate only a, only b, only c, both a and b (e.g., both a and b simultaneously), both a and c (e.g., both a and c simultaneously), both b and c (e.g., both b and c simultaneously), all a, b, and c, or variations thereof.

[0132] When describing embodiments of the inventive concept, the word "may" refers to "one or more embodiments of the inventive concept".

[0133] As used herein, the term "about" and similar terms are used as approximations and not as terms of degree, and are intended to describe the inherent bias in a measured or calculated value that would be recognized by one of ordinary skill in the art. As used herein, the term "about" includes the stated value and means within an acceptable range of deviation for a particular value, determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system). For example, "about" may mean within one or more standard deviations, or within ±30%, ±20%, ±10%, or ±5% of the stated value.

[0134] Furthermore, any numerical range set forth herein is intended to include all subranges of the same numerical precision falling within the set forth range. For example, the range “1.0 to 10.0” is intended to include (and inclusive) the stated minimum value of 1.0 and the stated maximum value of 10.0, that is, all subranges having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit set forth herein is intended to include all lower numerical limits falling within it, and any minimum numerical limit set forth in this specification is intended to include all higher numerical limits falling within it. Accordingly, the applicant reserves the right to amend this specification (including the claims) to expressly set forth any subranges falling within the range expressly set forth herein.

[0135] Here, unless otherwise specified, the listing of steps, tasks, or actions in a particular order does not necessarily imply that the invention or claims require that particular order. That is, the general rule is that unless the steps, tasks, or actions of a method (e.g., a method claim) actually specify the order, they should not be construed as requiring that order.

[0136] Those skilled in the art, in view of the full contents of this disclosure, will recognize that each suitable feature of the various embodiments of this disclosure may be combined in part or in whole, or combined with one another, and may be technically interlocked and operated in a variety of suitable ways. Unless otherwise stated or implied, each embodiment may be implemented independently of or in combination with one another in any suitable manner.

[0137] Display devices, electronic devices, means for manufacturing them (e.g., quantum dots), and / or any other related devices or components according to embodiments of the invention described herein can be implemented using any suitable hardware, firmware (e.g., application-specific integrated circuits), software, or a combination of software, firmware, and hardware. For example, various components of the device may be formed on an integrated circuit (IC) chip or on a separate IC chip. Furthermore, various components of the device may be implemented on a flexible printed circuit film, a tape-on-a-package (TCP), or a printed circuit board (PCB), or formed on a substrate. Additionally, various components of the device may be processes or threads that run on one or more processors in one or more computing devices, execute computer program instructions, and interact with other system components to perform the various functions described herein. The computer program instructions are stored in memory, which may be implemented using standard memory devices (such as, for example, random access memory (RAM)) in the computing device. The computer program instructions may also be stored in other non-transitory computer-readable media (such as, for example, CD-ROMs or flash drives). Furthermore, those skilled in the art will recognize that, without departing from the scope of this disclosure, the functions of various computing devices may be combined or integrated into a single computing device, or the functions of a dedicated computing device may be distributed across one or more other computing devices.

[0138] Although methods for manufacturing quantum dots, quantum dots, display devices, and electronic devices according to one or more embodiments have been described with reference to the accompanying drawings, the illustrated embodiments are exemplary and may be modified and altered by those skilled in the art without departing from the spirit of the technology described in the claims and their equivalents.

Claims

1. A method for manufacturing quantum dots, comprising: It forms a nucleus consisting of Ag and In; The nucleus was purified using a surface treatment solution containing Ga; as well as A shell is formed around the core by reacting a first precursor, including Ga, with the core.

2. The method according to claim 1, wherein the surface treatment solution comprises at least one selected from GaI3 and Ga(acac)3.

3. The method of claim 1, wherein the purification of the core is performed between the formation of the core and the formation of the shell.

4. The method according to claim 1, wherein after the purification of the nucleus, the peak emission wavelength of the photoluminescence spectrum of the nucleus is 600 nm or greater.

5. The method of claim 1, wherein the formation of the core comprises: A second precursor comprising Ag and a third precursor comprising In are added to the reaction vessel; as well as Add S to the reaction vessel. The second precursor includes at least one selected from AgF, AgCl, AgBr, AgI, Ag(NO3), Ag(OAc), Ag(acac), and Ag(DDTC), and The third precursor includes at least one selected from InF3, InCl3, InBr3, InI3, In(NO3)3, In(OAc)3, In(acac)3 and In(DDTC)3.

6. The method according to claim 5, wherein The addition of the second precursor and the third precursor is carried out at a first temperature, and The addition of S is carried out at the second temperature during the first duration.

7. The method according to claim 1, wherein the first precursor comprises at least one selected from GaF3, GaCl3, GaBr3, GaI3, Ga(NO3)3, Ga(OAc)3, Ga(acac)3 and Ga(DDTC)3.

8. The method of claim 1, wherein the core comprises AgInS2, and The shell comprises Ga.

9. A quantum dot, comprising: Including Ag and In cores; as well as A shell surrounding the core and comprising Ga and S. The quantum dot has a full width at half maximum (FWHM) of 50 nm or less in its emission wavelength, and the peak emission wavelength of the photoluminescence spectrum of the quantum dot is 600 nm or greater.

10. The quantum dot of claim 9, wherein the average diameter of the core is 4.5 nm or greater and 12 nm or less.

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