Abstract: The present invention provides a method of fabricating a semiconductor substrate and a method of fabricating a light emitting device. The method includes forming a first semiconductor layer on a substrate, forming a metallic material layer on the first semiconductor layer, forming a second semiconductor layer on the first semiconductor layer and the metallic material layer, wherein a void is formed in a first portion of the first semiconductor layer under the metallic material layer during formation of the second semiconductor layer, and separating the substrate from the second semiconductor layer by etching at least a second portion of the first semiconductor layer using a chemical solution.

Abstract: A light emitting diode (LED) having a modulation doped layer. The LED comprises an n-type contact layer, a p-type contact layer and an active region of a multiple quantum well structure having an InGaN well layer. The n-type contact layer comprises a first modulation doped layer and a second modulation doped layer, each having InGaN layers doped with a high concentration of n-type impurity and low concentration of n-type impurity InGaN layers alternately laminated. The InGaN layers of the first modulation doped layer have the same composition, and the InGaN layers of the second modulation doped layer have the same composition. The second modulation doped layer is interposed between the first modulation doped layer and the active region, and an n-electrode is in contact with the first modulation doped layer. Accordingly, an increase in process time is prevented and strains induced in a multiple quantum well structure are reduced.

Abstract: A light emitting diode (LED) having a modulation doped layer. The LED comprises an n-type contact layer, a p-type contact layer and an active region of a multiple quantum well structure having an InGaN well layer. The n-type contact layer comprises a first modulation doped layer and a second modulation doped layer, each having InGaN layers doped with a high concentration of n-type impurity and low concentration of n-type impurity InGaN layers alternately laminated. The InGaN layers of the first modulation doped layer have the same composition, and the InGaN layers of the second modulation doped layer have the same composition. The second modulation doped layer is interposed between the first modulation doped layer and the active region, and an n-electrode is in contact with the first modulation doped layer. Accordingly, an increase in process time is prevented and strains induced in a multiple quantum well structure are reduced.

Abstract: A light emitting diode (LED) has an n-type semiconductor layer, an active layer, a p-type semiconductor layer, and a transparent electrode layer. The LED includes a tunnel layer interposed between the p-type semiconductor layer and the transparent electrode layer, an opening arranged in the transparent electrode layer so that the tunnel layer is exposed, a distributed Bragg reflector (DBR) arranged in the opening, and an electrode pad arranged on the transparent electrode layer to cover the DBR in the opening.

Abstract: Disclosed are a light emitting device and a method of fabricating the same. The light emitting device comprises a substrate. A plurality of light emitting cells are disposed on top of the substrate to be spaced apart from one another. Each of the light emitting cells comprises a first upper semiconductor layer, an active layer, and a second lower semiconductor layer. Reflective metal layers are positioned between the substrate and the light emitting cells. The reflective metal layers are prevented from being exposed to the outside.

Abstract: A light emitting diode (LED) has an n-type semiconductor layer, an active layer, a p-type semiconductor layer, and a transparent electrode layer. The LED includes a tunnel layer interposed between the p-type semiconductor layer and the transparent electrode layer, an opening arranged in the transparent electrode layer so that the tunnel layer is exposed, a distributed Bragg reflector (DBR) arranged in the opening, and an electrode pad arranged on the transparent electrode layer to cover the DBR in the opening.

Abstract: The present invention provides a method of fabricating a semiconductor substrate and a method of fabricating a light emitting device. The method includes forming a first semiconductor layer on a substrate, forming a metallic material layer on the first semiconductor layer, forming a second semiconductor layer on the first semiconductor layer and the metallic material layer, wherein a void is formed in a first portion of the first semiconductor layer under the metallic material layer during formation of the second semiconductor layer, and separating the substrate from the second semiconductor layer by etching at least a second portion of the first semiconductor layer using a chemical solution.

Abstract: Disclosed is a method of fabricating a light emitting diode using a laser lift-off apparatus. The method includes growing an epitaxial layer including a first conductive-type compound semiconductor layer, an active layer and a second conductive-type compound semiconductor layer on a first substrate, bonding a second substrate, having a different thermal expansion coefficient from that of the first substrate, to the epitaxial layers at a first temperature of the first substrate higher than a room temperature, and separating the first substrate from the epitaxial layer by irradiating a laser beam through the first substrate at a second temperature of the first substrate higher than the room temperature but not more than the first temperature. Thus, during a laser lift-off process, focusing of the laser beam can be easily achieved and the epitaxial layers are prevented from cracking or fracture. The laser lift-off process is performed by a laser lift-off apparatus including a heater.

Abstract: Provided are a light emitting diode (LED) and a method for manufacturing the same. The LED includes an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. The active layer includes a well layer and a barrier layer that are alternately laminated at least twice. The barrier layer has a thickness at least twice larger than a thickness of the well layer.

Abstract: A light emitting diode (LED) has an n-type semiconductor layer, an active layer, a p-type semiconductor layer, and a transparent electrode layer. The LED includes a tunnel layer interposed between the p-type semiconductor layer and the transparent electrode layer, an opening arranged in the transparent electrode layer so that the tunnel layer is exposed, a distributed Bragg reflector (DBR) arranged in the opening, and an electrode pad arranged on the transparent electrode layer to cover the DBR in the opening.

Abstract: Disclosed is a light emitting device employing nanowire phosphors. The light emitting device comprises a light emitting diode for emitting light having a first wavelength with a main peak in an ultraviolet, blue or green wavelength range; and nanowire phosphors for converting at least a portion of light having the first wavelength emitted from the light emitting diode into light with a second wavelength longer than the first wavelength. Accordingly, since the nanowire phosphors are employed, it is possible to reduce manufacturing costs of the light emitting device and to reduce light loss due to non-radiative recombination.

Abstract: Disclosed is a light emitting device employing nanowire phosphors. The light emitting device comprises a light emitting diode for emitting light having a first wavelength with a main peak in an ultraviolet, blue or green wavelength range; and nanowire phosphors for converting at least a portion of light having the first wavelength emitted from the light emitting diode into light with a second wavelength longer than the first wavelength. Accordingly, since the nanowire phosphors are employed, it is possible to reduce manufacturing costs of the light emitting device and to reduce light loss due to non-radiative recombination.

Abstract: Disclosed are a light emitting diode employing an array of nanorods and a method of fabricating the same. The light emitting diode comprises an array of semiconductor nanorods positioned on a substrate. An upper electrode layer is deposited on the array of the nanorods such that an empty space remains between adjacent ones of the nanorods. Since the space between adjacent ones of the nanorods is not filled with an insulating material, the light extraction efficiency of a light emitting diode can be improved and a method of fabricating the light emitting diode can be simplified.

Abstract: Disclosed are a light emitting device and a method of fabricating the same. The light emitting device comprises a substrate. A plurality of light emitting cells are disposed on top of the substrate to be spaced apart from one another. Each of the light emitting cells comprises a first upper semiconductor layer, an active layer, and a second lower semiconductor layer. Reflective metal layers are positioned between the substrate and the light emitting cells. The reflective metal layers are prevented from being exposed to the outside.

Abstract: A method of forming a p-type compound semiconductor layer includes increasing a temperature of a substrate loaded into a reaction chamber to a first temperature. A source gas of a Group III element, a source gas of a p-type impurity, and a source gas of nitrogen containing hydrogen are supplied into the reaction chamber to grow the p-type compound semiconductor layer. Then, the supply of the source gas of the Group III element and the source gas of the p-type impurity is stopped and the temperature of the substrate is lowered to a second temperature. The supply of the source gas of nitrogen containing hydrogen is stopped and drawn out at the second temperature, and the temperature of the substrate is lowered to room temperature using a cooling gas. Accordingly, hydrogen is prevented from bonding to the p-type impurity in the p-type compound semiconductor layer.

Abstract: A light emitting diode (LED) having a modulation doped layer. The LED comprises an n-type contact layer, a p-type contact layer and an active region of a multiple quantum well structure having an InGaN well layer. The n-type contact layer comprises a first modulation doped layer and a second modulation doped layer, each having InGaN layers doped with a high concentration of n-type impurity and low concentration of n-type impurity InGaN layers alternately laminated. The InGaN layers of the first modulation doped layer have the same composition, and the InGaN layers of the second modulation doped layer have the same composition. The second modulation doped layer is interposed between the first modulation doped layer and the active region, and an n-electrode is in contact with the first modulation doped layer. Accordingly, an increase in process time is prevented and strains induced in a multiple quantum well structure are reduced.

Abstract: A method of forming a p-type compound semiconductor layer includes increasing a temperature of a substrate loaded into a reaction chamber to a first temperature. A source gas of a Group III element, a source gas of a p-type impurity, and a source gas of nitrogen containing hydrogen are supplied into the reaction chamber to grow the p-type compound semiconductor layer. Then, the supply of the source gas of the Group III element and the source gas of the p-type impurity is stopped and the temperature of the substrate is lowered to a second temperature. The supply of the source gas of nitrogen containing hydrogen is stopped and drawn out at the second temperature, and the temperature of the substrate is lowered to room temperature using a cooling gas. Accordingly, hydrogen is prevented from bonding to the p-type impurity in the p-type compound semiconductor layer.

Abstract: A method of forming a p-type compound semiconductor layer includes increasing a temperature of a substrate loaded into a reaction chamber to a first temperature. A source gas of a Group III element, a source gas of a p-type impurity, and a source gas of nitrogen containing hydrogen are supplied into the reaction chamber to grow the p-type compound semiconductor layer. Then, the supply of the source gas of the Group III element and the source gas of the p-type impurity is stopped and the temperature of the substrate is lowered to a second temperature. The supply of the source gas of nitrogen containing hydrogen is stopped and drawn out at the second temperature, and the temperature of the substrate is lowered to room temperature using a cooling gas. Accordingly, hydrogen is prevented from bonding to the p-type impurity in the p-type compound semiconductor layer.

Abstract: A light emitting diode (LED) has an n-type semiconductor layer, an active layer, a p-type semiconductor layer, and a transparent electrode layer. The LED includes a tunnel layer interposed between the p-type semiconductor layer and the transparent electrode layer, an opening arranged in the transparent electrode layer so that the tunnel layer is exposed, a distributed Bragg reflector (DBR) arranged in the opening, and an electrode pad arranged on the transparent electrode layer to cover the DBR in the opening.

Abstract: Provided are a light emitting diode (LED) and a method for manufacturing the same. The LED includes an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. The active layer includes a well layer and a barrier layer that are alternately laminated at least twice. The barrier layer has a thickness at least twice larger than a thickness of the well layer.