Abstract: There is provided a method of fabricating a semiconductor light emitting device, including: forming a sacrificial layer having a plurality of nanostructures on a growth substrate; forming a protective layer to cover the sacrificial layer; forming a light emitting structure by allowing a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer to be sequentially grown on the protective layer; etching the protective layer to expose the nanostructures; and separating the light emitting structure from the growth substrate by etching the exposed nanostructures, whereby damage and degradation of a light emitting structure at the time of the separation thereof may be prevented.

Abstract: A semiconductor light emitting device having enhanced luminous efficiency and a manufacturing method thereof are provided. The semiconductor light emitting device includes: an n-type semiconductor layer having at least one pit formed in an upper surface thereof; an active layer formed on the n-type semiconductor layer, a region of the active layer corresponding to the pit having an upper surface bent along the pit; and a p-type semiconductor layer formed on the active layer, a region of the p-type semiconductor layer corresponding to the pit having an upper surface bent along the bent portion of the active layer.

Abstract: There is provided a method of manufacturing a light emitting diode and a light emitting diode manufactured by the same. The method includes growing a first conductivity type nitride semiconductor layer and an undoped nitride semiconductor layer on a substrate sequentially in a first reaction chamber; transferring the substrate having the first conductivity type nitride semiconductor layer and the undoped nitride semiconductor layer grown thereon to a second reaction chamber; growing an additional first conductivity type nitride semiconductor layer on the undoped nitride semiconductor layer in the second reaction chamber; growing an active layer on the additional first conductivity type nitride semiconductor layer; and growing a second conductivity type nitride semiconductor layer on the active layer.

Abstract: Provided is a method of manufacturing a hexagonal boron nitride nanosheet to mass-produce a high-quality hexagonal boron nitride nanosheet at a low temperature in a safe process. The method of manufacturing a hexagonal boron nitride nanosheet includes (a) obtaining an alkali metal ion or alkali earth metal ion from a salt mixture including at least two kinds of alkali metal salt or alkali earth metal salt, (b) preparing a hexagonal boron nitride interlayer compound by inserting the alkali metal ion or alkali earth metal ion into layers of hexagonal boron nitride, and (c) obtaining a hexagonal boron nitride nanosheet by removing the alkali metal ion or alkali earth metal ion from the hexagonal boron nitride interlayer compound.

Abstract: A semiconductor light emitting device and a fabrication method thereof are provided. The semiconductor light emitting device includes: first and second conductivity-type semiconductor layers; and an active layer disposed between the first and second conductivity-type semiconductor layers and having a structure in which a quantum barrier layer and a quantum well layer are alternately disposed, and the quantum barrier layer includes first and second regions disposed in order of proximity to the first conductivity-type semiconductor layer.

Abstract: There is provided a chemical vapor deposition apparatus, including: a reaction chamber including a support part having a wafer placed thereon and a gas supply part supplying a process gas to a reactive space formed above the support part to allow a thin film to be grown on a surface of the wafer; a heat exchanger changing a temperature of the process gas, supplied to the reactive space through the gas supply part, to allow the process gas to be maintained at a set temperature: and a controller regulating a flow rate of the process gas, and detecting a temperature difference between a temperature of the process gas and the set temperature to thereby control the heat exchanger to supply the process gas to the reactive space while the process gas is maintained at a reference temperature set according to each stage.

Abstract: There is provided a nitride semiconductor light emitting device including an active layer having enhanced external quantum efficiency at both low and high current density. The nitride semiconductor light emitting device includes a first conductivity type nitride semiconductor layer; an active layer disposed on the first conductivity type nitride semiconductor layer and having a plurality of quantum well layers and at least one quantum barrier layer alternately arranged; and a second conductivity type nitride semiconductor layer disposed on the active layer. The plurality of quantum well layers disposed adjacent to each other include first and second quantum well layers having different thicknesses.

Abstract: A semiconductor light emitting device and a fabrication method thereof are provided. The semiconductor light emitting device includes: first and second conductivity-type semiconductor layers; and an active layer disposed between the first and second conductivity-type semiconductor layers and having a structure in which a quantum barrier layer and a quantum well layer are alternately disposed, and the quantum barrier layer includes first and second regions disposed in order of proximity to the first conductivity-type semiconductor layer.

Abstract: Provided is a nitride semiconductor light emitting device including p-type nitride semiconductor layer, an n-type nitride semiconductor layer, and an active layer formed therebetween. A contact layer is positioned between the p-type nitride semiconductor layer and a p-side electrode. The contact layer includes a first p-type nitride layer having a first impurity concentration to form ohmic contact with the p-side electrode and a second p-type nitride layer having a second impurity concentration, the second impurity concentration having a concentration lower than the first impurity concentration.

Abstract: There are provided a vapor deposition system, a method of manufacturing a light emitting device, and a light emitting device. A vapor deposition system according to an aspect of the invention may include: a first chamber having a first susceptor and at least one gas distributor discharging a gas in a direction parallel to a substrate disposed on the first susceptor; and a second chamber having a second susceptor and at least one second gas distributor arranged above the second susceptor to discharge a gas downwards. When a vapor deposition system according to an aspect of the invention is used, a semiconductor layer being thereby grown has excellent crystalline quality, thereby improving the performance of a light emitting device. Furthermore, while the operational capability and productivity of the vapor deposition system are improved, deterioration in an apparatus can be prevented.

Abstract: There is provided a method of fabricating a semiconductor light emitting device, including: forming a sacrificial layer having a plurality of nanostructures on a growth substrate; forming a protective layer to cover the sacrificial layer; forming a light emitting structure by allowing a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer to be sequentially grown on the protective layer; etching the protective layer to expose the nanostructures; and separating the light emitting structure from the growth substrate by etching the exposed nanostructures, whereby damage and degradation of a light emitting structure at the time of the separation thereof may be prevented.

Abstract: An objective lens drive apparatus configured to drive an objective lens that focuses a laser beam on an optical disk is disclosed, the apparatus including a holding member that holds the objective lens; at least one pair of drive magnets arranged to face each other at opposite sides of the holding member with respect a tangential direction that is parallel to a tangential line of the optical disk, the drive magnets having protruding end portions that protrude from each side of the holding member with respect to a tracking direction that is parallel to a radial direction of the optical disk; and plural drive coils configured to drive the holding member through interaction with the drive magnets, at least one of the drive coils being arranged on each side of the drive magnets with respect to the tangential direction.

Abstract: There is provided a method of manufacturing a light emitting diode and a light emitting diode manufactured by the same. The method includes growing a first conductivity type nitride semiconductor layer and an undoped nitride semiconductor layer on a substrate sequentially in a first reaction chamber; transferring the substrate having the first conductivity type nitride semiconductor layer and the undoped nitride semiconductor layer grown thereon to a second reaction chamber; growing an additional first conductivity type nitride semiconductor layer on the undoped nitride semiconductor layer in the second reaction chamber; growing an active layer on the additional first conductivity type nitride semiconductor layer; and growing a second conductivity type nitride semiconductor layer on the active layer.

Abstract: Provided are a method of packetizing encoded symbols and an apparatus using the same. The method includes an encoded symbol and target packet selection step of deciding a first source symbol and selecting an unpacketized first encoded symbol and a target packet into which the unpacketized first encoded symbol is inserted if there is the unpacketized first encoded symbol of at least one first encoded symbol, which is an encoded symbol of the first source symbol generated using an AND-OR tree structure, and a packetization step of generating a second source symbol based on at least one unpacketized first encoded symbol by use of the AND-OR tree structure, generating at least one second encoded symbol based on the second source symbol by use of the AND-OR tree structure, and packetizing at least one of second encoded symbols into the target packet along with the first encoded symbol.

Abstract: A semiconductor light emitting device includes: a semiconductor light emission stacked body including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer positioned between the first and second conductive semiconductor layers; and a highly conductive transparent electrode formed on at least one of the first and second conductive semiconductor layers and including a transparent electrode layer formed of at least one of a transparent conductive oxide layer and a transparent conductive nitride and a graphene layer allowing light within the visible spectrum to be transmitted therethrough, the transparent electrode layer and the graphene layer being stacked.

Abstract: The present invention relates to an apparatus for measuring a residual stress of an optical fiber. More particularly, the present invention relates to an apparatus for measuring residual stress of an optical fiber which is provided with a variable polarizer of which rotation is unnecessary instead of a rotary analyzer to measure the residual stress in high resolution and at high speed.

Abstract: Disclosed is a device for separating a propulsion system from a missile, the device including a locking unit configured to fix a propulsion system to a missile, a string disposed to cross a rear portion of the propulsion system to be broken by heat of the propulsion system, and an unlocking unit configured to unlock the missile by the broken string, whereby the number of additional components of an unlocking system can be reduced as many as possible so as to simplify the configuration of the apparatus, resulting in guaranteeing an enhanced performance of the missile, an easy assembly of the missile, and a reduction of a fabricating cost.

Abstract: A nitride semiconductor light emitting device includes a substrate, a first conductivity type nitride semiconductor layer disposed on the substrate and including a plurality of V-pits placed in a top surface thereof, a silicon compound formed in the vertex region of each of the V-pits, an active layer disposed on the first conductivity type nitride semiconductor layer and including depressions conforming to the shape of the plurality of V-pits, and a second conductivity type nitride semiconductor layer disposed on the active layer. The nitride semiconductor light emitting device, when receiving static electricity achieves high resistance to electrostatic discharge (ESD) since current is concentrated in the V-pits and the silicon compound placed on dislocations caused by lattice defects.

Abstract: There are provided a vapor deposition system, a method of manufacturing a light emitting device, and a light emitting device. A vapor deposition system according to an aspect of the invention may include: a first chamber having a first susceptor and at least one gas distributor discharging a gas in a direction parallel to a substrate disposed on the first susceptor; and a second chamber having a second susceptor and at least one second gas distributor arranged above the second susceptor to discharge a gas downwards. When a vapor deposition system according to an aspect of the invention is used, a semiconductor layer being thereby grown has excellent crystalline quality, thereby improving the performance of a light emitting device. Furthermore, while the operational capability and productivity of the vapor deposition system are improved, deterioration in an apparatus can be prevented.

Abstract: There is provided a nitride semiconductor light emitting device including an active layer having enhanced external quantum efficiency at both low and high current density. The nitride semiconductor light emitting device includes a first conductivity type nitride semiconductor layer; an active layer disposed on the first conductivity type nitride semiconductor layer and having a plurality of quantum well layers and at least one quantum barrier layer alternately arranged; and a second conductivity type nitride semiconductor layer disposed on the active layer. The plurality of quantum well layers disposed adjacent to each other include first and second quantum well layers having different thicknesses.