Patent application number | Description | Published |
20100140586 | QUANTUM DOTS HAVING COMPOSITION GRADIENT SHELL STRUCTURE AND MANUFACTURING METHOD THEREOF - Provided are quantum dots having a gradual composition gradient shell structure which have an improvedluminous efficiency and optical stability, and a method of manufacturing the quantum dots in a short amount of time at low cost. In the method, the quantum dots can be manufactured in a short amount of time at low cost using a reactivity difference between semiconductor precursors, unlike in uneconomical and inefficient conventional methods where shells areformed after forming cores and performing cleaning and redispersion processes. Also, formation of the cores is followed by formation of shells having a composition gradient. Thus, even if the shells are formed to a large thickness, the lattice mismatch between cores and shells is relieved. Furthermore, on the basis of the funneling concept, electrons and holes generated in the shells are transferred to the cores to emit light, thereby obtaining a high luminous efficiency of 80% or more. The quantum dot structure is not limited to Group II-IV semiconductor quantum dots but can be applied to other semiconductors quantum dots, such as Group III-V semiconductors quantum dots and Group IV-IV semiconductors quantum dots. Also, the manufacturing method can be utilized in the development of semiconductor quantum dots having different physical properties, and in various other fields. | 06-10-2010 |
20110156214 | STRUCTURE OF THIN NITRIDE FILM AND FORMATION METHOD THEREOF - Provided are a nitride thin film structure and a method of forming the same. If a nitride thin film is formed on a substrate that is not a nitride, many defects are generated by a difference in lattice constants between the substrate and the nitride thin film. Also, there is a problem of warping the substrate by a difference in thermal expansion coefficients between the substrate and the nitride thin film. In order to solve the problems, the present invention suggests a thin film structure in which after coating hollow particles, i.e. hollow structures on the substrate, the nitride thin film is grown thereon and the method of forming the thin film structure. According to the present invention, since an epitaxial lateral overgrowth (ELO) effect can be obtained by the hollow structures, high-quality nitride thin film can be formed. Since a refractive index in the thin film structure is adjusted, there is an effect of increasing light extraction efficiency during manufacturing the thin film structure into a light emitting device such as a light emitting diode (LED). Also, when thermal expansion coefficient of the substrate is greater than that of the nitride thin film, total stress of the nitride thin film is decreased according to the compression of the hollow structures in the nitride thin film such that there is also an effect of preventing warpage of the substrate. | 06-30-2011 |
20110227007 | METHOD OF MANUFACTURING QUANTUM DOT - A method of manufacturing a quantum dot, the method including: mixing of a Group II precursor and a Group III precursor in a solvent to prepare a first mixture; heating the first mixture at a temperature of about 200° C. to about 350° C.; adding a Group V precursor and a Group VI precursor to the first mixture while maintaining the first mixture at the temperature of about 200° C. to about 350° C. to prepare a second mixture; and maintaining the second mixture at the temperature of about 200° C. to about 350° C. to form a quantum dot. | 09-22-2011 |
20110227034 | QUANTUM DOT-BLOCK COPOLYMER HYBRID, METHODS OF FABRICATING AND DISPERSING THE SAME, LIGHT EMITTING DEVICE INCLUDING THE SAME, AND FABRICATION METHOD THEREOF - Disclosed are a quantum dot-block copolymer hybrid, methods of fabricating and dispersing the same, a light emitting device including the same, and a fabrication method thereof. The quantum dot-block copolymer hybrid includes; a quantum dot, and a block copolymer surrounding the quantum dot, wherein the block copolymer has a functional group comprising sulfur (S) and forms a chemical bond with the quantum dot. | 09-22-2011 |
20120315391 | QUANTUM DOTS HAVING COMPOSITION GRADIENT SHELL STRUCTURE AND MANUFACTURING METHOD THEREOF - Provided are quantum dots having a gradual composition gradient shell structure which have an improved luminous efficiency and optical stability, and a method of manufacturing the quantum dots in a short amount of time at low cost. In the method, the quantum dots can be manufactured in a short amount of time at low cost using a reactivity difference between semiconductor precursors, unlike in uneconomical and inefficient conventional methods where shells are formed after forming cores and performing cleaning and redispersion processes. Also, formation of the cores is followed by formation of shells having a composition gradient. | 12-13-2012 |
20140016207 | OPTICAL FILM WITH PARTIALLY COATED STRUCTURE ARRAY AND MANUFACTURING METHOD THEREOF - The present invention relates to an optical film comprising a substrate on which an array of structures is formed, wherein a material having a different refractive index, absorbancy or reflectivity from that of a surface of the structures is partially coated on the surface of the structures, and a manufacturing method thereof. Specifically, the optical film according to one embodiment of the present invention may have a different transparency depending on the direction or can transmit light asymmetrically. Further, the optical film may be applicable to image devices, which need to change brightness or images depending on the angle of view or to display three-dimensional images. | 01-16-2014 |
20140326297 | THREE-DIMENSIONAL ELECTRODE ON DYE-SENSITIZED SOLAR CELL AND METHOD FOR MANUFACTURING THE SAME - The present invention relates to a photoelectrode for a dye-sensitized solar cell including inorganic nanoparticles, wherein a three-dimensional pattern is formed on the surface of the photoelectrode. The three-dimensional photoelectrode for a dye-sensitized solar cell according to the present invention has a micrometer-sized pattern and thus exhibits an improved light absorption caused by a total reflection and a increased light path. | 11-06-2014 |
20150087137 | NITRIDE THIN FILM STUCTURE AND METHOD OF FORMING THE SAME - Provided are a nitride thin film structure and a method of forming the same. If a nitride thin film is formed on a substrate that is not a nitride, many defects are generated by a difference in lattice constants between the substrate and the nitride thin film. Also, there is a problem of warping the substrate by a difference in thermal expansion coefficients between the substrate and the nitride thin film. In order to solve the problems, the present invention suggests a thin film structure in which after coating hollow particles, i.e. hollow structures on the substrate, the nitride thin film is grown thereon and the method of forming the thin film structure. According to the present invention, since an epitaxial lateral overgrowth (ELO) effect can be obtained by the hollow structures, high-quality nitride thin film can be formed. Since a refractive index in the thin film structure is adjusted, there is an effect of increasing light extraction efficiency during manufacturing the thin film structure into a light emitting device such as a light emitting diode (LED). Also, when thermal expansion coefficient of the substrate is greater than that of the nitride thin film, total stress of the nitride thin film is decreased according to the compression of the hollow structures in the nitride thin film such that there is also an effect of preventing warpage of the substrate. | 03-26-2015 |