Abstract: Provided are a light emitting device, a light emitting device package, and a lighting system. The light emitting device comprises a reflective layer, a second conductive type semiconductor layer on the reflective layer, an active layer on the second conductive type semiconductor layer, a first conductive type semiconductor layer on the active layer, and a pad electrode on the first conductive type semiconductor layer. The reflective layer comprises a predetermined pattern.

Abstract: A light emitting device package includes: a package body having a first cavity; an electrode layer comprising a first electrode and a second electrode which are electrically isolated from each other; a light emitting device electrically connected to the electrode layer on the package body; a protective device disposed in a second cavity formed at the package body and electrically connected to the electrode layer; a reflective layer on the protective device; and a molding part on the light emitting device, wherein at least one of the first electrode and the second electrode is disposed on the package body.

Abstract: Provided are a quantum dot laser diode and a method of manufacturing the same. The method of manufacturing a quantum dot laser diode includes the steps of: forming a grating structure layer including a plurality of gratings on a substrate; forming a first lattice-matched layer on the grating structure layer; forming at least one quantum dot layer having at least one quantum dot on the first lattice-matched layer; forming a second lattice-matched layer on the quantum dot layer; forming a cladding layer on the second lattice-matched layer; and forming an ohmic contact layer on the cladding layer. Consequently, it is possible to obtain high gain at a desired wavelength without affecting the uniformity of quantum dots, so that the characteristics of a laser diode can be improved.

Abstract: A light emitting device package includes: a package body having a first cavity; an electrode layer comprising a first electrode and a second electrode which are electrically isolated from each other; a light emitting device electrically connected to the electrode layer on the package body; a protective device disposed in a second cavity formed at the package body and electrically connected to the electrode layer; a reflective layer on the protective device; and a molding part on the light emitting device, wherein at least one of the first electrode and the second electrode is disposed on the package body.

Abstract: Provided are a light emitting device, a light emitting device package, and a lighting system. The light emitting device comprises a reflective layer, a second conductive type semiconductor layer on the reflective layer, an active layer on the second conductive type semiconductor layer, a first conductive type semiconductor layer on the active layer, and a pad electrode on the first conductive type semiconductor layer. The reflective layer comprises a predetermined pattern.

Abstract: A quantum dot laser diode and a method of fabricating the same are provided. The quantum dot laser diode includes: a first clad layer formed on an InP substrate; a first lattice-matched layer formed on the first clad layer; an active layer formed on the first lattice-matched layer, and including at least one quantum dot layer formed of an InAlAs quantum dot or an InGaPAs quantum dot which is grown by an alternate growth method; a second lattice-matched layer formed on the active layer; a second clad layer formed on the second lattice-matched layer; and an ohmic contact layer formed on the second clad layer.

Abstract: A quantum dot laser diode and a method of fabricating the same are provided. The quantum dot laser diode includes: a first clad layer formed on an InP substrate; a first lattice-matched layer formed on the first clad layer; an active layer formed on the first lattice-matched layer, and including at least one quantum dot layer formed of an InAlAs quantum dot or an InGaPAs quantum dot which is grown by an alternate growth method; a second lattice-matched layer formed on the active layer; a second clad layer formed on the second lattice-matched layer, and an ohmic contact layer formed on the second clad layer.

Abstract: Provided is a method of forming quantum dots, including: forming a buffer layer on an InP substrate so as to be lattice-matched with the InP substrate; and sequentially alternately depositing In(Ga)As layers and InAl(Ga)As or In(Ga, Al, As)P layers that are greatly lattice-mismatched with each other on the buffer layer so as to form In(Ga, Al)As or In(Ga, Al, P)As quantum dots.

Abstract: Provided are a quantum dot laser diode and a method of manufacturing the same. The method of manufacturing a quantum dot laser diode includes the steps of: forming a grating structure layer including a plurality of gratings on a substrate; forming a first lattice-matched layer on the grating structure layer; forming at least one quantum dot layer having at least one quantum dot on the first lattice-matched layer; forming a second lattice-matched layer on the quantum dot layer; forming a cladding layer on the second lattice-matched layer; and forming an ohmic contact layer on the cladding layer. Consequently, it is possible to obtain high gain at a desired wavelength without affecting the uniformity of quantum dots, so that the characteristics of a laser diode can be improved.

Abstract: Provided is a distributed feedback semiconductor laser structure including: a first clad layer; a first ridge waveguide formed on the first clad layer; an active layer formed on the first ridge waveguide; a second ridge waveguide formed on the active layer; a second clad layer formed on the second ridge waveguide; an ohmic contact layer formed on the second clad layer; and a plurality of gratings formed in at least one of the first and second clad layers, making a predetermined angle with the first ridge waveguide or the second ridge waveguide, and periodically arranged in a longitudinal direction of the first or second ridge waveguide. As a result, a general hologram lithography process capable of mass production is applied to the present invention so that process time can be reduced. Also, a distributed feedback semiconductor laser structure using a quantum-dot active layer that does not require an additional process for obtaining a pure single-wavelength is provided.

Abstract: Provided are a quantum dot laser diode and a method of manufacturing the same. The method of manufacturing a quantum dot laser diode includes the steps of: forming a grating structure layer including a plurality of gratings on a substrate; forming a first lattice-matched layer on the grating structure layer; forming at least one quantum dot layer having at least one quantum dot on the first lattice-matched layer; forming a second lattice-matched layer on the quantum dot layer; forming a cladding layer on the second lattice-matched layer; and forming an ohmic contact layer on the cladding layer. Consequently, it is possible to obtain high gain at a desired wavelength without affecting the uniformity of quantum dots, so that the characteristics of a laser diode can be improved.

Abstract: Provided are a semiconductor laser diode and a method of manufacturing the same. The semiconductor laser diode includes a lower cladding layer disposed on a substrate; a ridge including an optical waveguide layer, an active layer, an upper cladding layer, and an ohmic contact layer, which are sequentially stacked on the lower cladding layer, and having a predetermined width, which is obtained by performing a channel etching process on both sides of the ridge; an oxide layer disposed on surfaces of the upper and lower cladding layer to control the width of the ridge; a dielectric layer disposed on left and right channels of the ridge; an upper electrode layer disposed on the entire surface of the resultant structure to enclose the ridge and the dielectric layer; and a lower electrode layer disposed on a bottom surface of the substrate. The method is simpler than a conventional process of manufacturing a semiconductor laser diode.

Abstract: Provided is a distributed feedback semiconductor laser structure including: a first clad layer; a first ridge waveguide formed on the first clad layer; an active layer formed on the first ridge waveguide; a second ridge waveguide formed on the active layer; a second clad layer formed on the second ridge waveguide; an ohmic contact layer formed on the second clad layer; and a plurality of gratings formed in at least one of the first and second clad layers, making a predetermined angle with the first ridge waveguide or the second ridge waveguide, and periodically arranged in a longitudinal direction of the first or second ridge waveguide. As a result, a general hologram lithography process capable of mass production is applied to the present invention so that process time can be reduced. Also, a distributed feedback semiconductor laser structure using a quantum-dot active layer that does not require an additional process for obtaining a pure single-wavelength is provided.

Abstract: Provided are a quantum dot laser diode and a method of manufacturing the same. The method of manufacturing a quantum dot laser diode includes the steps of: forming a grating structure layer including a plurality of gratings on a substrate; forming a first lattice-matched layer on the grating structure layer; forming at least one quantum dot layer having at least one quantum dot on the first lattice-matched layer; forming a second lattice-matched layer on the quantum dot layer; forming a cladding layer on the second lattice-matched layer; and forming an ohmic contact layer on the cladding layer. Consequently, it is possible to obtain high gain at a desired wavelength without affecting the uniformity of quantum dots, so that the characteristics of a laser diode can be improved.

Abstract: Provided is a method of forming quantum dots, including: forming a buffer layer on an InP substrate so as to be lattice-matched with the InP substrate; and sequentially alternately depositing In(Ga)As layers and InAl(Ga)As or In(Ga, Al, As)P layers that are greatly lattice-mismatched with each other on the buffer layer so as to form In(Ga, Al)As or In(Ga, Al, P)As quantum dots.

Abstract: The distributed feedback semiconductor laser includes: a lower clad layer formed on a substrate; a ridge including an active layer and an upper clad layer sequentially formed on the lower clad layer; and a grating formed at a sidewall or both sidewalls of the ridge including the active layer in a direction perpendicular to the active layer and a resonance axis so as to enable a single longitudinal mode oscillation. The grating has parallel grooves that are equally spaced at a period equal to an integer multiple of half of an oscillation wavelength ? (n?/2, n=1, 2, 3 . . . ).

Abstract: Provided is a method of forming quantum dots in which the quantum dots are formed on a thin InxGa1-xAs strained layer. The In(Ga)As quantum dots can be applied to an active layer of an optical device such as a laser diode or an optical detector.

Abstract: Provided are a semiconductor laser diode and a method of manufacturing the same. The semiconductor laser diode includes a lower cladding layer disposed on a substrate; a ridge including an optical waveguide layer, an active layer, an upper cladding layer, and an ohmic contact layer, which are sequentially stacked on the lower cladding layer, and having a predetermined width, which is obtained by performing a channel etching process on both sides of the ridge; an oxide layer disposed on surfaces of the upper and lower cladding layer to control the width of the ridge; a dielectric layer disposed on left and right channels of the ridge; an upper electrode layer disposed on the entire surface of the resultant structure to enclose the ridge and the dielectric layer; and a lower electrode layer disposed on a bottom surface of the substrate. The method is simpler than a conventional process of manufacturing a semiconductor laser diode.