KR-102962652-B1 - Method for producing quantum dot, quantum dot produced by the same, and photo device comprising the quantum dot

Abstract

In one aspect, a method for manufacturing quantum dots is provided, comprising: (a) a step of preparing a quantum dot seed solution; (b) a step of continuously injecting a quantum dot cluster solution into the quantum dot seed solution to grow quantum dots; (c) a step of separating the grown quantum dots and redispersing them in a solvent; and (d) a step of continuously injecting the quantum dot cluster solution into the redispersed quantum dots to further grow the quantum dots.

Inventors

• 조경상
• 정소희
• 김태완
• 양유성
• 박성민

Assignees

• 삼성전자주식회사
• 성균관대학교산학협력단

Dates

Publication Date

20260507

Application Date

20210318

Claims (20)

1. (a) Step of preparing a quantum dot seed solution; (b) a step of growing quantum dots by continuously injecting a quantum dot cluster solution into the quantum dot seed solution; (c) a step of separating the grown quantum dots and redispersing them in a solvent; and (d) a step of continuously injecting a quantum dot cluster solution into the redistributed quantum dots to further grow the quantum dots; a method for manufacturing quantum dots comprising:
2. In Article 1, A method for manufacturing quantum dots in which steps (b) and (d) are performed until the quantum dots of each step each have a constant size.
3. In Article 1, A method for manufacturing quantum dots by repeating steps (c) and (d) until the quantum dots grow to a predetermined size.
4. In Article 1, A method for manufacturing quantum dots in which the above quantum dots are group II-VI, group III-V, or group IV-VI compound semiconductor materials.
5. In Article 1, A method for manufacturing quantum dots in which the above quantum dots are selected from the group consisting of GaN, GaP, GaAs, GaSb, InN, InP, InAs, InGaAs, InSb, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, ZnO, ZnS, ZnSe, ZnTe, ZnCdSe, ZnCdTe, ZnCdS, CdS, CdSe, CdSeTe, CdSeZn, CdTe, HgS, HgSe, HgTe, GeSe, and GeTe.
6. (a) Step of preparing an InAs quantum dot seed solution; (b) a step of growing InAs quantum dots by continuously injecting an InAs quantum dot cluster solution into the above InAs quantum dot seed solution; (c) a step of separating the above InAs quantum dots; and (d) a step of continuously injecting an InAs quantum dot cluster solution into the InAs quantum dots to further grow the InAs quantum dots; a method for manufacturing InAs quantum dots comprising:
7. In Article 6, A method for manufacturing InAs quantum dots having a diameter of 3 nm to 12 nm of the finally grown InAs quantum dots.
8. In Article 6, A method for manufacturing InAs quantum dots in which the finally grown InAs quantum dots have an absorption wavelength of 1400 nm to 1600 nm.
9. In Article 6, A method for manufacturing InAs quantum dots in step (b) above, wherein the InAs quantum dot seed solution is a solution heated to 100-350°C.
10. In Article 6, A method for manufacturing InAs quantum dots in the above step (b), wherein the InAs quantum dot cluster solution is at room temperature.
11. In Article 6, The above step (b) is a method for manufacturing InAs quantum dots, which is performed until the InAs quantum dots have a constant size.
12. In Article 6, The above step (b) is a method for manufacturing InAs quantum dots, which is performed until the InAs quantum dots have a constant absorption wavelength.
13. In Article 6, The above step (b) is a method for manufacturing InAs quantum dots, which is performed until the absorption wavelength of the InAs quantum dots does not change.
14. In Article 6, A method for manufacturing InAs quantum dots by repeating steps (c) and (d) until the InAs quantum dots grow to a predetermined size.
15. In Article 6, A method for manufacturing InAs quantum dots by rapidly injecting an As precursor solution into a heated In precursor solution to prepare the InAs quantum dot seed solution.
16. In Article 6, A method for manufacturing InAs quantum dots, wherein an In precursor solution and an As precursor solution are reacted at room temperature in a ratio (volume ratio) of 11:1 to 1:11 to prepare the InAs quantum dot cluster solution.
17. Manufactured by the manufacturing method of paragraph 6, and InAs quantum dots having an absorption peak at wavelengths between 1500 nm and 1600 nm.
18. In Article 17, The absorption peak above corresponds to the first exciton peak of the InAs quantum dot, an InAs quantum dot.
19. An optical device comprising a light-absorbing layer containing InAs quantum dots of claim 17.
20. In Article 19, An optical device including a photodetector.

Description

Method for producing quantum dot, quantum dot produced by the same, and photo device comprising the quantum dot The present invention relates to a method for manufacturing quantum dots, quantum dots manufactured by the same, and an optical device comprising quantum dots. InAs quantum dots, which possess a small bulk bandgap, are expected to be utilized in electronic devices in the near-infrared and infrared regions. Meanwhile, since the optical and electronic properties of quantum dots are controlled by their size, ensuring size uniformity is critical. Strategies to control size uniformity by manipulating the reactivity of precursors in the synthesis of InAs quantum dots have demonstrated their limitations. Recently, a continuous precursor injection process has been proposed and reported to improve size uniformity and reaction yield (Nature communications, 2016, 7, 12749 and Chemistry of Materials, 2016, 28(22), 8119). However, in the continuous injection process, as the injection of the precursor (cluster) solution continues, the concentration of the precursor (cluster) present in the solution decreases, and the distance between the precursor (cluster) and the quantum dot increases. Consequently, in diffusion-dependent growth, which creates quantum dots of uniform size, the diffusion rate of the precursor (cluster) decreases, thereby reducing the growth rate of the quantum dot. Furthermore, due to the increase in excess precursor (cluster) that did not participate in the reaction, reaction-dependent growth occurs, resulting in non-uniform quantum dot size and secondary nucleation, which stops the growth of the quantum dot. According to prior reports, the absorption wavelength of InAs quantum dots is limited to 1200 nm, which falls short of the 1300 nm and 1550 nm required for optical communication, etc. FIG. 1 is a flowchart illustrating a method for manufacturing quantum dots according to one embodiment. Figure 2 is a diagram showing that the volume of the reaction solution does not increase beyond a certain volume due to the separation and redispersion of quantum dots in a continuous injection process according to one embodiment. Figure 3 is a TEM image of the InAs quantum dots prepared in Example 1. Figure 4 is a graph showing the size distribution of InAs quantum dots prepared in Example 1. Figure 5 is a graph showing the volume of quantum dots according to the injection rate of the quantum dot cluster solution during the preparation of InAs quantum dots of Example 1. Figure 6 is the absorption spectrum in the short-wavelength infrared region of the InAs quantum dots prepared in Example 1. FIG. 7 is a schematic diagram of a JFET device (10) using InAs quantum dots manufactured in Example 1 in the light absorption layer. Figure 8 is an Id-Vd graph of the optical element of Example 2 when irradiated with a laser light of 1310 nm wavelength and when not irradiated. FIG. 9 is a graph showing the response (A/W) according to the drain voltage (Vd) for a gate voltage (Vg) of 0.5 V of the optical device of Example 2, according to the intensity of the irradiated light. Hereinafter, a method for manufacturing quantum dots according to one embodiment will be described in more detail. In this specification, "quantum dot seed" is a crystalline material that serves as a seed for growing quantum dots to a desired size. "Quantum dot seed solution" is a solution containing quantum dot seeds and a solvent, and may further include components such as quantum dot precursors and ligands. In this specification, "quantum dot precursor" refers to a material containing a component that constitutes a quantum dot, used in the manufacture of quantum dots. In this specification, "quantum dot precursor solution" means a solution containing a quantum dot precursor. In this specification, "ligand" refers to a substance that coordinates to the surface of a quantum dot during the quantum dot synthesis process to help disperse the quantum dot or change the properties of the quantum dot surface. In this specification, "quantum dot cluster" means an amorphous aggregate or composite composed of components constituting quantum dots. In this specification, "first excitonic peak" refers to an absorption peak having a wavelength corresponding to the bandgap of the exciton. (Quantum dot manufacturing method) FIG. 1 is a flowchart illustrating a method for manufacturing quantum dots according to one embodiment. Referring to the flowchart of FIG. 1, a quantum dot seed solution is first prepared (S10). The quantum dot material may be a compound semiconductor of group II-VI, group III-V, or group IV-VI containing, for example, two, three, or four elements. The quantum dot material may include, for example, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InGaAs, InSb, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, ZnO, ZnS, ZnSe, ZnTe, ZnCdSe, ZnCdTe, ZnCdS, CdS, CdSe, CdSeTe, CdSeZn, CdTe, HgS, HgSe, HgTe, GeSe, or GeTe. Quantum dot seeds can be formed by reacti