Qd substrate manufacturing method using multi-functionalised electrophoresis, and full color qled using same

Abstract

The present invention relates to a substrate comprising a patterned optical waveguide, comprising: an optical waveguide extending, in at least one direction, with directivity on a substrate; and a quantum dot layer formed on the surface of the optical waveguide, the quantum dot layer in which quantum dots are dispersed in an organic medium.

Description

Method for manufacturing QD substrate using multifunctional electrophoresis method and full-color QLED using the same

[0001] The present invention relates to a method for forming a multi-resonance structure by forming an electron transport layer of a self-luminous quantum dot light-emitting diode and controlling its thickness.

[0002] The development of patternable quantum dots (QDs) has attracted much attention due to their outstanding optical and electrical properties, such as broad absorption, narrow emission spectra with photoluminescence quantum yields close to 1, size-tunable band gaps, and high stability.

[0003] Based on these advantageous characteristics, the demand for stable, vivid, high-resolution quantum dot light-emitting diodes (QLEDs) for various advanced display applications such as head-up displays and XR has grown significantly.

[0004] XR devices, in particular, can offer highly immersive technologies that can transport users into virtual reality (VR), overlay digital information on the real world (augmented reality; AR), and seamlessly blend VR and AR (mixed reality). To maximize these user experiences, implementation of the latest 8K display technology, known as a horizontally formatted, high-resolution device with 8,000 pixels, may be necessary. Implementing such high-resolution displays could reduce the visualization of pixel grids, allowing for more immersive and realistic virtual environment experiences.

[0005]

[0006] However, despite numerous studies, fabricating uniform, nano-sized quantum dots in an intended pattern and implementing white QLEDs remains challenging.

[0007] Several known studies have proposed patternable QD technologies, including inkjet printing, contact transfer printing, and photolithography patterning, to achieve high-resolution implementation of QDs and facilitate their integration into self-luminous red, green, and blue (RGB) QLEDs to achieve these goals. However, these printing methods have had problems in stably patterning fine QDs to ensure industrial applicability and achieve ultra-high resolution due to issues with inkjet nozzles, reliability of stamps, color alignment issues in flexible molds, and optical loss issues due to the use of high-energy cross-linking sources.

[0008] The present invention is intended to introduce a technology introduced to solve the above-described purpose, and proposes a technology that enables high throughput and selective and sequential placement of nano-pixelated QDs (~500 nm) without increasing the difficulty of the manufacturing process by introducing a multi-functionalized electrophoretic deposition (MEPD) system technology.

[0009] A method for manufacturing a QD pattern using a multifunctional electrophoretic method according to one embodiment of the present invention comprises the steps of preparing a ZnO nanoparticle solution and a QD solution, respectively; connecting a target electrode and a counter electrode to a power supply; and connecting a transparent substrate to the target electrode and immersing the target electrode in the ZnO nanoparticle solution and the counter electrode in the QD solution, respectively.

[0010] In one embodiment, the ZnO nanoparticle solution may be acidic.

[0011] According to one embodiment, the target electrode may include ITO (Indium Tin Oxide).

[0012] In one embodiment, the QD may have a ligand on its surface that has a negative charge.

[0013] In one embodiment, the ligand on the QD surface may be substituted using mercaptopropionic acid.

[0014] In one embodiment, the target electrode may have a bank connected to at least one side having a lower surface energy than the target electrode.

[0015] In one embodiment, the bank may comprise SU-8 and function to effectively deposit QDs on the pattern of the target electrode.

[0016] According to one embodiment, the size of each QD light-emitting particle forming the QD pattern may be from several hundred nanometers to several micrometers.

[0017]

[0018] According to one embodiment, each of the QD light-emitting particles forming the QD pattern may include light-emitting particles of different sizes, and at least some of the light-emitting particles of different sizes may be formed through the same electrophoretic process.

[0019]

[0020] A method for manufacturing an RGB full-color QD pattern using a multi-functional electrophoretic method according to another embodiment of the present invention includes a step of forming each of the R, G, and B QD patterns using separate ITO electrodes in a method for manufacturing an RGB QD pattern on a substrate.

[0021] According to one embodiment, the QD pattern may be manufactured using a method for manufacturing a QD pattern using a multifunctional electrophoretic method according to an embodiment of the present invention.

[0022]

[0023] A QD pattern using a multifunctional electrophoretic method according to another embodiment of the present invention includes a plurality of QD light-emitting particles formed on a substrate, the QD light-emitting particles forming an array pattern, and the pattern of the QD light-emitting particles may be manufactured using a manufacturing method according to an embodiment of the present invention.

[0024] According to one embodiment, the plurality of QD light-emitting particles include QD light-emitting particles of different sizes, and the QD light-emitting particles may be hundreds of nanoscale to several microscale.

[0025]

[0026] A full-color QLED manufactured using a multifunctional electrophoretic method according to another embodiment of the present invention includes a plurality of QD patterns, at least some of the QD patterns are formed by stacking a plurality of QDs, and includes pixels of R, G, and B colors, the R and G pixels are connected in parallel and the B pixels are connected in series, and the QD pattern may be a QD pattern according to an embodiment of the present invention.

[0027] In one embodiment, the full-color QLED may have a number of subpixels of color B greater than the number of subpixels of color R and G.

[0028] According to embodiments proposed in the present invention, the same deposition method can be used for ZnO nanoparticles (NPs) and QDs, thereby ensuring versatility in the approach. This has the advantage of enabling the implementation of a white QLED by precisely controlling individual red, green, and blue pixels. In other words, according to embodiments proposed in the present invention, the deposition of nano-pixelated ZnO nanoparticles and QDs for implementing a white QLED can be successfully performed.

[0029] According to embodiments proposed in the present invention, a novel multifunctional electrophoretic deposition (MEPD) method enables rapid arrangement of QDs at precisely desired locations. Furthermore, this multifunctional electrophoretic deposition process enables successful patterning of ZnO nanoparticles to reduce crosstalk issues and the operation of RGB QD-based EL devices controllable by individual electrodes.

[0030] More specifically, the novel patterning techniques proposed in the embodiments of the present invention utilize two different substrates and spatially separate them, thereby enabling complete separation of RGB QDs, thereby realizing the smallest QD pixel size ever reported (~500 nm).

[0031] That is, the multifunctional electrophoretic deposition method proposed in the present invention can be an efficient and practical method for realizing pixel patterning, color coordinate control, and RGB full-color QLED display.

[0032] The embodiments proposed in the present invention can form pixels ranging in size from several micrometers to several hundred nanometers, ranging from small, medium and large.

[0033] However, the effects of the present invention are not limited to the effects described above, and include all effects naturally implemented due to the various configurations proposed in the present invention.

[0034] FIG. 1 is a schematic diagram showing a configuration in which a multifunctional electrophoretic deposition (MEPD) system according to one embodiment of the present invention is implemented.

[0035] FIG. 2 is an image showing the characteristics of a nano-electrophoresis (EPD) process and a nano-pixelated QD pattern according to one embodiment of the present invention.

[0036] FIG. 3 is an image showing a full color patterning process for a high-resolution EL device using a multi-functional electrophoretic deposition system according to one embodiment of the present invention and an example implemented therefrom.

[0037] FIG. 4 shows the results of confirming the characteristics of an RGB QLED implemented using a multifunctional electrophoretic deposition system according to one embodiment of the present invention.

[0038]

[0039] The embodiments of the present invention are provided for the purpose of illustrating the technical concept of the present invention. The scope of the rights of the present invention is not limited to the embodiments presented below or the specific descriptions of these embodiments.

[0040] All technical and scientific terms used in this invention, unless otherwise defined, have the meanings commonly understood by those skilled in the art to which this invention pertains. All terms used in this invention have been selected for the purpose of more clearly explaining the invention and are not intended to limit the scope of the rights provided for in this invention.

[0041] Expressions such as “comprising,” “having,” and the like used in the present invention should be understood as open-ended terms that imply the possibility of including other embodiments, unless otherwise stated in the phrase or sentence in which the expression is included.

[0042] The singular expressions described in the present invention may include plural meanings unless otherwise stated, and this also applies to the singular expressions described in the claims.

[0043]

[0044] Hereinafter, with reference to the embodiments illustrated in FIGS. 1 to 4, the QD patterning technology proposed in the present invention through a novel multifunctional electrophoretic deposition method and respective implementation examples will be described in detail in four steps. The embodiments of the present invention propose a technology that enables position control by adopting an electroflow method for ZnO nanoparticles dispersed in a polar solvent, overcoming the limitations of the manufacturing method of QD light-emitting diodes that have been limited to the conventional quantum dot patterning method.

[0045]

[0046] Previous studies have reported large-area, full-color patterning processes that selectively deposit QDs via electrophoretic deposition (EPD). However, these electrophoretic studies required pixelated electrodes to be connected by thin metal lines, as the deposition of RGB QDs was controlled by the potential difference between two different electrodes on the same substrate. Consequently, extremely high electric fields were required to deposit QDs on the pixelated substrate, necessitating the fabrication of individually pixelated RGB QLEDs and the deposition of nanoparticles (NPs), and several additional challenges, such as low compatibility with other charge transport layers. For these reasons, the development of an innovative electrophoretic method was essential to achieve completely independent pixelation of RGB QDs and nanoparticles.

[0047] In an embodiment of the present invention, a novel multifunctional electrophoretic deposition (MEPD) method is proposed to achieve individual RGB full-color QD patterning. According to one embodiment of the present invention, the new patterning technique can completely spatially separate RGB QDs by applying two different substrates consisting of pixelated SU-8 banks on an ITO electrode and a counter electrode. In the embodiment, by spatially separating the two different substrates, the smallest QD pixel size reported to date (~500 nm) can be realized.

[0048]

[0049] Furthermore, embodiments of the present invention can significantly reduce the electric field used in multifunctional electrophoretic deposition (MEPD) by forming negatively charged, water-dispersible QDs through ligand modification (e.g., using 3-mercaptopropionic acid (MPA)). This approach allows for precise and rapid alignment of QDs at desired locations. Through this multifunctional electrophoretic deposition process, the inventors have successfully patterned ZnO nanoparticles to reduce crosstalk issues and have demonstrated for the first time the operation of RGB QD-based EL devices controllable by individual electrodes, thereby completing the present invention.

[0050]

[0051] Introduction of a multifunctional electrophoretic deposition method

[0052] FIG. 1 is a schematic diagram showing a configuration in which a multifunctional electrophoretic deposition (MEPD) system according to one embodiment of the present invention is implemented.

[0053] More specifically, Fig. 1(a) is a schematic diagram schematically showing a ligand modification method for MEPD, showing that a pristine oleic acid (OA) ligand is exchanged with a negatively charged mercaptopropionic acid (MPA) ligand. Fig. 1(b) is a graph of zeta potential analysis using capped QDs of (OA) and (c) MPA, and each inset image illustrates the advantages of a multifunctional electrophoretic deposition (MEPD) system and the possibility of selective QD deposition. Fig. 1(d) is a schematic diagram of a multifunctional electrophoretic deposition system using two different electrodes according to an embodiment of the present invention, in which an SU-8 bank patterned on an ITO electrode and a counter electrode are immersed in the same ZnO nanoparticle (or QD) solution. The two electrodes are each interconnected through the same power supply. Figure 1(e) is a schematic diagram showing the deposition process of ZnO nanoparticles (upper image) and QD layer (lower image) in a multifunctional electrophoretic deposition system.

[0054]

[0055] In an embodiment of the present invention, a ligand modification method for high-resolution and large-area QLED displays can be adopted to form individually well-established RGB QDs at desired locations.

[0056] In one embodiment, a ligand such as oleic acid (hereinafter referred to as OA) may be used to modify pure QDs. Additionally, a negatively charged ligand such as mercaptopropionic acid (hereinafter referred to as MPA) may be utilized to electrically mobilize the QDs under a potential difference.

[0057] When the solvent of QDs with MPA ligands is changed from non-polar solvents such as toluene and hexane to polar solvent such as deionized water (DIW), the zeta potential peak (ζ) value of the QDs can be clearly observed. Unlike the broad distribution of pure QDs in Fig. 1(b), the ζ value of MPA-capped QDs in Fig. 1(c) shows a sharp peak at -45.1 mV, indicating that they are not strongly attracted to a specific charge. This means that while pristine QDs are deposited on all electrodes under low electric field conditions, MPA-capped QDs are selectively deposited, which means that pure QDs may also be deposited on the opposite electrode, resulting in material waste. While electrophoretic deposition (EPD) processes using non-aqueous solvents typically require hundreds or thousands of V (volts), the multifunctional electrophoretic deposition (MEPD) process according to the embodiments of the present invention required only less than 5 V.

[0058]

[0059] In addition, in the multifunctional electrophoretic deposition process according to an embodiment of the present invention, the surface energy contrast between the banks and ITO is greatly amplified, thereby preventing QDs from being deposited on banks with low surface energy, while allowing them to be effectively deposited on very fine ITO patterns with relatively high surface energy and experiencing a stronger electric field. At this time, the inventors of the present invention confirmed that selective deposition is possible even in the multifunctional electrophoretic deposition (MEPD) method based on the fact that ZnO nanoparticles (QDs) are dispersed in a polar solvent such as butanol. Through this, similar to aqueous electrophoretic deposition (EPD), a lower applied voltage and a faster processing speed can be realized compared to the electrophoretic deposition method using a non-polar solvent.

[0060]

[0061] In a specific example, preparation of two separate solutions, one for the ZnO nanoparticles and one for the QDs, and the other for the cathode and anode lines of an appropriate power supply may be required to ensure precise deposition of the MPA-capped QDs.

[0062] As confirmed in FIG. 1(e), the multifunctional electrophoretic deposition (MEPD) method according to one embodiment of the present invention can be performed including the following steps: (i) preparing a ZnO nanoparticle and QD solution, (ii) interconnecting a counter electrode (ITO) and a target substrate to a power supply, and (iii) immersing the two substrates in an applied voltage.

[0063] At this time, the deposition of ZnO nanoparticles and QDs can be processed sequentially for the purpose of reducing leakage current caused by unwanted formation in the SU-8 region.

[0064]

[0065] Nanopixel QD films through process optimization

[0066] FIG. 2 is an image showing the characteristics of a nano-electrophoresis (EPD) process and a nano-pixelated QD pattern according to one embodiment of the present invention.

[0067] More specifically, Fig. 2(a) shows a simulation of QD film formation as a function of process time in COMSOL. Fig. 2(b) shows a fluorescence image of a 2 μm Х 6 μm R-QD pixel array, which clearly shows individual sub-pixels with very uniform PL brightness. Fig. 2(c) shows an FE-SEM image of QDs deposited in a 2 μm Х 6 μm sub-pixel bank structure and a cross-sectional TEM image of the deposited QDs. The SEM image of Fig. 2(c) confirms that the QDs are selectively packed in the banks to form a very uniform film, and the TEM image confirms that a uniform film with a thickness of one to two layers is implemented. At this time, Al can be formed to protect the QD layer from penetrating during the platinum (Pt) coating and to easily identify the QD layer. At this time, the Al deposition can be deposited using a thermal evaporation method.

[0068] The results in Fig. 2(d) indicate that lines of multiple scales were simultaneously generated in a single process, suggesting that the multifunctional electrophoretic deposition process can be performed without increasing the process difficulty depending on the pattern size. Fig. 2(d) simultaneously displays fluorescent images of nano- to micro-scale QD patterns. This image shows that Sungnyemun, a national treasure of Korea, was expressed using two sizes of QD circular patterns, with a 500 nm circle used to express the outline of Sungnyemun and a 2 μm circle used as the background. The image includes line patterns with widths of 4, 2, and 1 μm, which were introduced to demonstrate the simplicity and efficiency of the patterning process, as well as the smallest pattern reported to date, which is 500 nm. Thus, the multifunctional electrophoretic deposition process of the present invention can form patterns of various sizes on a single substrate, and all of this is achieved within a single electrophoretic deposition process, suggesting the broad potential of this technology. Furthermore, the aforementioned examples demonstrate that the intended purpose can be achieved through electrical migration and deposition processes alone, without the need for complex new process steps, in order to introduce various patterns in shape and size. The enlarged fluorescence image on the right confirms that the entire image is well-filled with uniform nano- and micro-scale patterns.

[0069] Figure 2(e) is an image of MEPD (Multifunctional Electrophoretic Deposition) formed with a 500 nm blue dot array pattern.

[0070]

[0071] In the above example, the MPA-capped QDs possess a negative zeta potential, allowing them to electrically migrate in DIW. Because they are subject to various repulsive and interactive forces in an electric field, understanding the factors that contribute to achieving a uniform surface morphology of the QD film is essential for producing high-resolution and efficient QLEDs.

[0072] The present inventors observed the changing QD concentration while applying voltage at transient μs intervals to patterned ITO through COMSOL simulations as shown in Fig. 2(a). They confirmed that the QDs were initially observed at the edge of the ITO, showing an asymmetric distribution, and then concentrated at the center of the ITO electrode until the QDs reached a steady state. These simulation results were also implemented in actual QD deposition experiments, and in some examples, a more uniform film shape was secured using the Taguchi method, one of the process optimization design theories.

[0073] Unlike previously reported selective electrophoretic deposition (SEPD) methods that require thin metal lines, the described examples clearly demonstrate the feasibility of implementing individual QD pixel structures using two different substrates, a novel approach. Furthermore, the highest applied voltage in these examples was approximately 25 times lower than that achieved with previously reported SEPD methods.

[0074]

[0075] Sequential full-color QD deposition using multifunctional electrophoretic deposition

[0076] FIG. 3 is an image showing a full color patterning process for a high-resolution EL device using a multi-functional electrophoretic deposition system according to one embodiment of the present invention and an example implemented therefrom.

[0077] More specifically, FIG. 3(a) is an image showing a process for implementing full-color patterning using a nano-electrophoretic deposition (EPD) method according to one embodiment, wherein each R, G, and B QD can be deposited at a desired location through separate ITO electrodes. In the above embodiment, each of the red and green electrodes is connected in parallel to each pad, and the blue electrode is connected in series, and can be designed to have twice as many subpixels as other colors to compensate for the low luminance of blue itself. By design, each electrode is used sequentially in the electrophoretic deposition process to enable rapid generation of a full-color pattern.

[0078] Fig. 3(b) shows PL images of full-color patterns manufactured by multi-functional electrophoretic deposition (MEPD) method. The left image shows a 10 μm x 30 μm subpixel full-color pattern on a 13 μm wide ITO electrode. Each subpixel is spaced 5 μm apart, and each ITO electrode is spaced 2 μm apart. Also, the middle PL image shows a 4 μm x 12 μm subpixel full-color pattern. Due to process limitations in manufacturing the ITO electrode, two subpixels of the same color are implemented on the 13 μm electrode. The right image is a full-color pattern with 2 μm Х 6 μm subpixels. For the same reason as the middle image, three subpixels of the same color are placed on a single-width ITO electrode.

[0079] Figure 3(c) is an image of a traditional Korean painting implemented using QDs. This image is composed of about one million dots filled with QDs, as can be seen in the fluorescence microscope image of the QDs stacked on the right.

[0080]

[0081] To fabricate RGB full-color QD patterns using embodiments of the present invention, separate ITO electrodes for each color with SU-8 bank structures may be necessary. In this case, the ITO electrodes may be introduced individually for deposition of RGB QDs.

[0082] As shown in Figure 3(a), a multifunctional electrophoretic deposition process can be performed to create full-color QD patterns using designed pads and electrodes. Each process involves separate RGB electrodes, and by manipulating surface energy differences, each color can be selectively deposited without mixing. This allows for full-color patterns with sub-pixels of 10, 4, and 2 μm, as shown in Figure 3(b).

[0083] According to an embodiment of the present invention, the implemented fluorescence image shows uniform photoluminescence (PL) brightness in all pixel areas, and in particular, it can be confirmed that B QDs in the B color are uniformly deposited with the designed electrode without potential drop.

[0084] The image in Fig. 3(c) is a replica of a traditional Korean painting, Minhwa (a painting of lotus flowers and carp), designed using an embodiment of the present invention, which is expressed similarly to pointillism using about 1 million SU-8 circles of 10 μm in size. The yellow color in the image was created by stacking G QDs on R QDs within a single circle pattern, the purple color was created by stacking R QDs and B QDs, and the cyan color was also created by stacking G QDs and B QDs. The result of the mixed colors by the stacked QDs is shown on the right side of Fig. 3(c). This means that the functional electrophoretic deposition method can stack additional QDs by repeating the process. In this case, since white cannot be expressed by stacking the three primary colors of QDs due to the disturbance of the absorption-emission spectra of G QDs and B QDs, it can be expressed by arranging R, G, and B pixels.

[0085]

[0086] RGB QLED using multifunctional electrophoretic deposition

[0087] FIG. 4 shows the results of confirming the characteristics of an RGB QLED implemented using a multifunctional electrophoretic deposition system according to one embodiment of the present invention.

[0088] More specifically, Fig. 4(a) is a schematic diagram showing the structure of a stack of fabricated individual RGB QLEDs, and Fig. 4(b) is a corresponding energy diagram of the RGB QLED. Figs. 4(c) to 4(f) are graphs showing results depending on spin-casted and multifunctional electrophoretic deposition (MEPD) ZnO nanoparticles, wherein Fig. 4(c) is a JV characteristic, Fig. 4(d) is a LV characteristic, Fig. 4(e) is an EQE-J characteristic, and Fig. 4(f) is a normalized EL intensity graph of the RGB QLED. In addition, Fig. 4(g) is a photograph showing the operating results of an RGB EL device with a full-color pattern showing red, green, blue, magenta, yellow, cyan, and white, and Fig. 4(h) is an image showing the position of the MEPD scheme according to an embodiment of the present invention on the CIE coordinates.

[0089]

[0090] In one embodiment, a multifunctional electrophoretic deposition (MEPD) method was utilized to achieve high-resolution and white QLEDs, maximizing advantages such as precise control of the emission area, reduced crosstalk issues, high contrast ratio, and high pixel density. However, despite these various advantages, the MEPD process is also used to form ZnO NPs to effectively minimize crosstalk issues. This is because the high electron mobility of ZnO NPs typically affects the creation of leakage paths, which can accelerate current flow to unwanted areas, i.e., areas without QD EMLs. In this sense, SU-8 banks can be formatted to ensure continuous and selective formation of ETL / EMLs, thereby distinguishing individual RGB QD pixels, as shown in Fig. 4(a). Based on this, we performed multifunctional electrophoretic deposition on a pixelated ITO array on a glass substrate, confirming that the deposition of ZnO NPs can be positioned.

[0091] Based on various analyses, the inventors were able to fabricate individual patterned RGB QLEDs as arrays with pixel sizes of 2 μm Х 6 μm. The proposed device in Fig. 4(a) consists of glass / ITO / ZnO NP / RGB QD / 4,4-bis(9-carbazolyl)-biphenyl):2,2'-bis(4-(carbazol-9-yl)phenyl)biphenyl (CBP:BCBP) / MoOx / Al 10.

[0092] At this time, the OA ligand of the QD emission layer (EML) was exchanged with the corresponding MPA ligand, and the energy diagram of the corresponding RGB QLED is shown in Figure 4(b).

[0093] To compare the device performance of RGB QLEDs based on spin-casted and MEPD-based ZnO NPs, the current density-voltage (JV), luminance-voltage (LV), external quantum efficiency (EQE), and normalized EL spectra are shown in Figs. 4(c) to 4(f). As shown in these figures, it can be confirmed again that the leakage current and turn-on voltage of the QLED according to the embodiment of the present invention are significantly reduced compared to the QLED based on spin-casted ZnO nanoparticles. Consequently, the EQE of the RGB QLED was also dramatically improved by a factor of 6 to 10, and the normalized EL spectra showed similar FWHM.

[0094] In one embodiment, based on these experiments, a full-color QLED capable of emitting light from a single color such as red, green, blue, magenta, yellow, cyan, and white to multiple colors was successfully implemented (Fig. 4(g)), and the color gamut of the QLED according to one embodiment of the present invention implemented based on these results is illustrated in Fig. 4(h).

[0095]

[0096] The above description is merely an illustrative example of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

Claims

1. Step of preparing ZnO nanoparticle solution and QD solution respectively; A step of connecting the target electrode and the counter electrode to a power supply; and A step of connecting a transparent substrate to the target electrode and immersing the target electrode in a ZnO nanoparticle solution and the counter electrode in a QD solution, respectively; Method for manufacturing QD patterns using multifunctional electrophoresis.

2. In paragraph 1, The above ZnO nanoparticle solution is acidic. Method for manufacturing QD patterns using multifunctional electrophoresis.

3. In paragraph 1, The above target electrode comprises ITO (Indium Tin Oxide). Method for manufacturing QD patterns using multifunctional electrophoresis.

4. In paragraph 1, The above QD has a surface ligand with a negative charge. Method for manufacturing QD patterns using multifunctional electrophoresis.

5. In paragraph 4, The ligand on the surface of the above QD is substituted using mercaptopropionic acid. Method for manufacturing QD patterns using multifunctional electrophoresis.

6. In paragraph 1, The above target electrode has a bank connected to at least one side having a lower surface energy than the target electrode. Method for manufacturing QD patterns using multifunctional electrophoresis.

7. In paragraph 6, The above bank, Including SU-8, Functioning to effectively deposit QDs on the pattern of the above target electrode, Method for manufacturing QD patterns using multifunctional electrophoresis.

8. In paragraph 1, The size of each QD light-emitting particle forming the above QD pattern is from several hundred nanometers to several micrometers. Method for manufacturing QD patterns using multifunctional electrophoresis.

9. In paragraph 1, Each QD light-emitting particle forming the above QD pattern contains light-emitting particles of different sizes, At least some of the above different sized luminescent particles are formed through the same electrophoretic process. Method for manufacturing QD patterns using multifunctional electrophoresis.

10. A method for manufacturing an RGB QD pattern on a substrate, A step of forming each QD pattern of R, G and B using separate ITO electrodes, Method for manufacturing RGB full-color QD patterns using multifunctional electrophoresis.

11. In paragraph 10, The above QD pattern is manufactured using a method for manufacturing a QD pattern using the multifunctional electrophoresis method of the first clause. Method for manufacturing RGB full-color QD patterns using multifunctional electrophoresis.

12. Containing a plurality of QD light-emitting particles formed on a substrate, The above QD light-emitting particles form an array pattern, The pattern of the above QD light-emitting particles is manufactured using the manufacturing method of claim 1. QD patterning using multifunctional electrophoresis.

13. In paragraph 12, The above plurality of QD light-emitting particles include QD light-emitting particles of different sizes, The above QD light-emitting particles are hundreds of nanoscale to several microscale. QD patterning using multifunctional electrophoresis.

14. Containing multiple QD patterns, At least some of the above QD patterns are formed by stacking multiple QDs; It has pixels of all colors R, G and B, The pixels of R and G above are connected in parallel and the pixels of B are connected in series. The above QD pattern is the QD pattern of clause 12. Full-color QLED manufactured using a multi-functional electrophoresis method.

15. In paragraph 14, The above full color QLED is, The number of subpixels of color B is greater than the number of subpixels of colors R and G. Full-color QLED manufactured using a multi-functional electrophoresis method.

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