Abstract: The present invention relates to a light-emitting device using a clad layer consisting of asymmetric units, wherein the clad layer is provided by repeatedly stacking a unit having an asymmetric energy bandgap on upper and lower portions of an active layer, and the inflow of both electrons and holes into the active layer is arbitrarily controlled through the clad layer, so that the internal quantum efficiency can be improved. The light-emitting device using the clad layer consisting of the asymmetric units according to the present invention is characterized in that the clad layer is provided on at least one of the upper and lower portions of the active layer and consists of one or plural units, wherein the unit has a structure in which the first to nth unit layers (n is a natural number equal to or greater than three) having different energy bandgaps are sequentially stacked and has an asymmetric energy band diagram.

Abstract: A method of manufacturing a light generating device with required wavelength is disclosed. According to the method, a) a required wavelength is determined. b) A polar angle and an azimuthal angle corresponding to the required wavelength in a nitride semiconductor are determined. Then, c) a nitride semiconductor crystal is grown according to the polar angle and the azimuthal angle. Therefore, a light generating device with required wavelength may be manufactured without adjusting amounts of elements of compound semiconductor.

Abstract: The present invention relates to a nitride semiconductor light emitting device using a hybrid buffer layer and a method for fabricating the same which can minimize the lattice mismatch between a buffer layer and a nitride semiconductor. The method for fabricating the nitride semiconductor light emitting device using the hybrid buffer layer includes a first step of forming an AlxGa1-xN(0?x<1) layer on a substrate, a second step of forming a three-dimensional crystal seed layer made of a material included in a general formula of AlxGa1-xN(0?x<1) and AlOyNz on the substrate by recrystallizing the substrate with the AlxGa1-xN(0?x<1) layer thereon, and a third step of forming an AlN nanostructure by annealing the substrate subjected to the second step at NH3 gas atmosphere, thus forming a hybrid buffer layer composed of the three-dimensional crystal seed layer and the AlN nanostructure on the substrate.

Abstract: A method of manufacturing a light generating device with required wavelength is disclosed. According to the method, a) a required wavelength is determined. b) A polar angle and an azimuthal angle corresponding to the required wavelength in a nitride semiconductor are determined. Then, c) a nitride semiconductor crystal is grown according to the polar angle and the azimuthal angle. Therefore, a light generating device with required wavelength may be manufactured without adjusting amounts of elements of compound semiconductor.

Abstract: The present disclosure relates to a semiconductor light-emitting device which includes: a light-emitting layer composed of an active layer and of barrier layers formed as superlattice layers and disposed on and under the active layer to relieve stresses applied to the active layer and reduce the sum of electric fields generated in the active layer by the spontaneous polarization and the piezo; an N-type contact layer injecting electrons into the light-emitting layer; and a P-type contact layer disposed opposite to the N-type contact layer with respect to the light-emitting layer and injecting holes into the light-emitting layer, wherein the active layer contains InGaN, and the barrier layers are formed by alternately stacking of an AlGaN thin film and an InGaN thin film.

Abstract: The present invention relates to a light-emitting device using a clad layer consisting of asymmetric units, wherein the clad layer is provided by repeatedly stacking a unit having an asymmetric energy bandgap on upper and lower portions of an active layer, and the inflow of both electrons and holes into the active layer is arbitrarily controlled through the clad layer, so that the internal quantum efficiency can be improved. The light-emitting device using the clad layer consisting of the asymmetric units according to the present invention is characterized in that the clad layer is provided on at least one of the upper and lower portions of the active layer and consists of one or plural units, wherein the unit has a structure in which the first to nth unit layers (n is a natural number equal to or greater than three) having different energy bandgaps are sequentially stacked and has an asymmetric energy band diagram.

Abstract: The present invention relates to III-nitride semiconductor light emitting device and a method for fabricating the same. The III-nitride semiconductor light emitting device includes: a substrate; a plurality of III-nitride semiconductor layers grown over the substrate and including an active layer for generating light by recombination of electrons and holes; and a protrusion formed on a surface of the substrate over which the semiconductor layers are to be grown, a section of the protrusion which is in parallel to the growth direction of the semiconductor layers being formed in a triangular shape.

Abstract: There is provided a compound semiconductor light emitting device capable of optimizing strain applied to an active layer and a clad layer to minimize a piezoelectric field and spontaneous polarization in an active layer and to maximize light emission efficiency. In a compound semiconductor light emitting device having a structure in which a buffer layer, a first clad layer, an active layer, and a second clad layer are sequentially deposited, a strain induction layer and a strain control layer intersect at least once and are deposited between the buffer layer and the first clad layer, the strain induction layer performs induction so that compressive strain to be applied to the active layer is dispersed to the strain control layer, and the compressive strain applied to the active layer is reduced as the compressive strain is applied to the strain control layer.

Abstract: There is provided a light emitting device using a compound semiconductor, which can improve electrical characteristics and internal quantum efficiency by maximizing the recombination rate of electrons and holes in an active layer. The light emitting device using a compound semiconductor includes a substrate; a compound semiconductor layer formed on the substrate, the compound semiconductor layer comprising an active layer; and a current spreading layer formed on at least one of the top and bottom surfaces of the active layer, the current spreading layer allowing electrons or holes to be uniformly spread into the active layer.

Abstract: The present disclosure relates to a III-nitride semiconductor light emitting device, including: a substrate; a plurality of III-nitride semiconductor layers grown over the substrate and including an active layer generating light by recombination of electrons and holes; a scattering surface provided on the substrate to scatter the light generated in the active layer; and a sub-scattering portion ruggedly formed on the scattering surface.

Abstract: There is provided a compound semiconductor light emitting device capable of optimizing strain applied to an active layer and a clad layer to minimize a piezoelectric field and spontaneous polarization in an active layer and to maximize light emission efficiency. In a compound semiconductor light emitting device having a structure in which a buffer layer, a first clad layer, an active layer, and a second clad layer arc sequentially deposited, a strain induction layer and a strain control layer intersect at least once and are deposited between the buffer layer and the first clad layer, the strain induction layer performs induction so that compressive strain to be applied to the active layer is dispersed to the strain control layer, and the compressive strain applied to the active layer is reduced as the compressive strain is applied to the strain control layer.

Abstract: Disclosed are a light-emitting diode and a method for fabricating the same. The ternary or quaternary Group III-V nitride semiconductor light-emitting diode comprises a buffer layer doped with conductive impurities and developed with an orientation inclined toward the axis [1122] at an angle of 40° to 70° with respect to the axis [0001] on a [0001]-oriented substrate, a light-emitting layer arranged on the buffer layer, a first electrode arranged under the buffer layer, and a second electrode arranged on the light-emitting layer, wherein the light-emitting layer includes a first clad layer arranged on the buffer layer, an activation layer arranged on the first clad layer and a second clad layer arranged on the activation layer.

Abstract: The invention relates to a nitride semiconductor LED using a hybrid buffer layer with a minimum lattice mismatch between the buffer layer and the nitride semiconductor and a fabrication method therefor. The fabrication method of a nitride semiconductor LED using a hybrid buffer layer comprises: a first step, in which an AlxGa1-xN (0?x<1) layer is formed over a semiconductor; a second step, in which a crystalline seed layer of a 3D structure and AlOyNz are formed over the substrate, the crystalline seed layer being formed by recrystallizing the substrate with the AlxGa1-xN (0?x<1) layer formed thereover and containing a substance with a general formula of AlxGa1-xN (0?x<1); and a third step, in which the substrate having gone through the second step is subject to heat treatment under NH3 gas atmosphere to form an AlN nano structure, thus forming over the substrate a hybrid buffer layer consisting of the 3D crystalline seed layer and the AlN nano structure.