Abstract: Disclosed are an ultraviolet measuring device, a photodetector, an ultraviolet detector, an ultraviolet index calculation device, and an electronic device or portable terminal including the same. In one aspect, an ultraviolet measuring is provided to comprise: a substrate on which an electrode is formed; a readout integrated circuit (ROTC) unit electrically connected with the electrode; and an aluminum gallium nitride (AlGaN) based UVB sensor electrically connected with the readout integrated circuit unit and formed on an insulating substrate, wherein the read-out integrated circuit converts a photocurrent input from the UV sensor into a digital signal including UV data.

Abstract: Exemplary embodiments provide a UV light emitting diode and a method of fabricating the same. The method of fabricating a UV light emitting diode includes growing a first n-type semiconductor layer including AlGaN, wherein growth of the first n-type semiconductor layer includes changing a growth pressure within a growth chamber and changing a flow rate of an n-type dopant source introduced into the growth chamber. A pressure change during growth of the first n-type semiconductor layer includes at least one cycle of a pressure increasing period and a pressure decreasing period over time, and change in flow rate of the n-type dopant source includes increasing the flow rate of the n-type dopant source in the form of at least one pulse. The UV light emitting diode fabricated by the method has excellent crystallinity.

Abstract: A UV light emitting device includes: an n-type contact layer including an AlGaN layer or an AlInGaN layer; a p-type contact layer including a AlGaN layer or an AlInGaN layer; and an active layer of a multi-quantum well structure placed between the n-type contact layer and the p-type contact layer. The active area of the multi-quantum well structure includes barrier layers and well layers. The well layers include electrons and holes present according to probability distributions thereof. The barrier layers are formed of AlInGaN or AlGaN and have an Al content of 10% to 30%. At least one of the barrier layers disposed between the well layers has a smaller thickness than of the well layers and at least one of the barrier layers placed between the well layers has a thickness and a band gap preventing electrons and holes injected into and confined in a well layer adjacent to the barrier layer from spreading into another adjacent well layer.

Abstract: Disclosed is a near UV light emitting device. The light emitting device includes an n-type contact layer, a p-type contact layer, an active area of a multi-quantum well structure disposed between the n-type contact layer and the p-type contact layer, and at least one electron control layer disposed between the n-type contact layer and the active area. Each of the n-type contact layer and the p-type contact layer includes an AlInGaN or AlGaN layer, and the electron control layer is formed of AlInGaN or AlGaN. In addition, the electron control layer contains a larger amount of Al than adjacent layers to obstruct flow of electrons moving into the active area. Accordingly, electron mobility is deteriorated, thereby improving recombination rate of electrons and holes in the active area.

Abstract: Exemplary embodiments provide a UV light emitting diode and a method of fabricating the same. The method of fabricating a UV light emitting diode includes growing a first n-type semiconductor layer including AlGaN, wherein growth of the first n-type semiconductor layer includes changing a growth pressure within a growth chamber and changing a flow rate of an n-type dopant source introduced into the growth chamber. A pressure change during growth of the first n-type semiconductor layer includes at least one cycle of a pressure increasing period and a pressure decreasing period over time, and change in flow rate of the n-type dopant source includes increasing the flow rate of the n-type dopant source in the form of at least one pulse. The UV light emitting diode fabricated by the method has excellent crystallinity.

Abstract: Disclosed are an ultraviolet measuring device, a photodetector, an ultraviolet detector, an ultraviolet index calculation device, and an electronic device or portable terminal including the same. In one aspect, an ultraviolet measuring is provided to comprise: a substrate on which an electrode is formed; a readout integrated circuit (ROTC) unit electrically connected with the electrode; and an aluminum gallium nitride (AlGaN) based UVB sensor electrically connected with the readout integrated circuit unit and formed on an insulating substrate, wherein the read-out integrated circuit converts a photocurrent input from the UV sensor into a digital signal including UV data.

Abstract: A method of forming a light detection device includes forming a non-porous layer on a substrate, forming a light absorption layer on the non-porous layer, the light absorption layer including pores formed in a surface thereof, forming a Schottky layer on the surface of the light absorption layer and in the pores thereof, and forming a first electrode layer on the Schottky layer.

Abstract: Exemplary embodiments provide a UV light emitting diode and a method of fabricating the same. The method of fabricating a UV light emitting diode includes growing a first n-type semiconductor layer including AlGaN, wherein growth of the first n-type semiconductor layer includes changing a growth pressure within a growth chamber and changing a flow rate of an n-type dopant source introduced into the growth chamber. A pressure change during growth of the first n-type semiconductor layer includes at least one cycle of a pressure increasing period and a pressure decreasing period over time, and change in flow rate of the n-type dopant source includes increasing the flow rate of the n-type dopant source in the form of at least one pulse. The UV light emitting diode fabricated by the method has excellent crystallinity.

Abstract: Disclosed are a substrate regeneration method and a regenerated substrate. The substrate regeneration method comprises preparing a substrate having a surface separated from an epitaxial layer. The separated surface includes a convex portion and a concave portion, and the convex portion is comparatively flatter than the concave portion. A crystalline restoration layer is grown on the separated surface. The crystalline restoration layer is grown on the convex portion. Furthermore, a surface roughness improvement layer is grown on the crystalline restoration layer, thereby providing a continuous surface. Accordingly, it is possible to provide a regenerated substrate, which has a flat surface, without using physical polishing or chemical etching technology.

Abstract: A light detection device includes a substrate, a buffer layer disposed on the substrate, a first band gap change layer disposed on a portion of the buffer layer, a light absorption layer disposed on the first band gap change layer, a Schottky layer disposed on a portion of the light absorption layer, and a first electrode layer disposed on a portion of the Schottky layer.

Abstract: An ultraviolet (UV) photo-detecting device, including: a substrate; a first nitride layer disposed on the substrate; a second nitride layer disposed between the first nitride layer and the substrate; a light absorption layer disposed on the first nitride layer; and a Schottky junction layer disposed on the light absorption layer.

Abstract: A light detection device includes a substrate, a buffer layer disposed on the substrate, a first band gap change layer disposed on a portion of the buffer layer, a light absorption layer disposed on the first band gap change layer, a Schottky layer disposed on a portion of the light absorption layer, and a first electrode layer disposed on a portion of the Schottky layer.

Abstract: Exemplary embodiments provide a UV light emitting diode and a method of fabricating the same. The method of fabricating a UV light emitting diode includes growing a first n-type semiconductor layer including AlGaN, wherein growth of the first n-type semiconductor layer includes changing a growth pressure within a growth chamber and changing a flow rate of an n-type dopant source introduced into the growth chamber. A pressure change during growth of the first n-type semiconductor layer includes at least one cycle of a pressure increasing period and a pressure decreasing period over time, and change in flow rate of the n-type dopant source includes increasing the flow rate of the n-type dopant source in the form of at least one pulse. The UV light emitting diode fabricated by the method has excellent crystallinity.

Abstract: A UV light emitting diode and a method of fabricating the same are provided. The light emitting diode includes an active area between an n-type nitride-based semiconductor layer and a p-type nitride-based semiconductor layer, wherein the active area includes a plurality of barrier layers containing Al, a plurality of well layers containing Al and alternately arranged with the barrier layer, and at least one conditioning layer. Each conditioning layer is placed between the well layer and the barrier layer adjacent to the well layer and is formed of a binary nitride semiconductor. The design of the conditioning layer can reduce stress of the active area while allowing uniform control of the composition of the well layers and/or the barrier layers.

Abstract: A UV light emitting device and a method for fabricating the same are disclosed. The method includes forming a first super-lattice layer including AlxGa(1-x)N on a substrate, forming a sacrificial layer including AlzGa(1-z)N on the first super-lattice layer, partially removing the sacrificial layer, forming an epitaxial layer on the sacrificial layer, and separating the substrate from the epitaxial layer, wherein the sacrificial layer includes voids, the substrate is separated from the epitaxial layer at the sacrificial layer, and forming an epitaxial layer includes forming an n-type semiconductor layer including n-type AluGa(1-u)N (0<u?z?x<1). With this structure, the light emitting device can emit UV light and be separated from the substrate.

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: Exemplary embodiments provide a UV light emitting diode and a method of fabricating the same. The method of fabricating a UV light emitting diode includes growing a first n-type semiconductor layer including AlGaN, wherein growth of the first n-type semiconductor layer includes changing a growth pressure within a growth chamber and changing a flow rate of an n-type dopant source introduced into the growth chamber. A pressure change during growth of the first n-type semiconductor layer includes at least one cycle of a pressure increasing period and a pressure decreasing period over time, and change in flow rate of the n-type dopant source includes increasing the flow rate of the n-type dopant source in the form of at least one pulse. The UV light emitting diode fabricated by the method has excellent crystallinity.

Abstract: A photo-detecting device includes a first nitride layer, a light absorption layer disposed on the first nitride layer, and a Schottky junction layer disposed on the light absorption layer. According to a photoluminescence (PL) properties measurement of the photo-detecting device, a first peak light intensity is greater than a second peak light intensity, and the first peak light intensity is a peak light intensity of light emitted from the light absorption layer, and the second peak light intensity is a peak light intensity of light emitted from the first nitride layer.

Abstract: An ultraviolet (UV) photo-detecting device, including: a substrate; a first nitride layer disposed on the substrate; a second nitride layer disposed between the first nitride layer and the substrate; a light absorption layer disposed on the first nitride layer; and a Schottky junction layer disposed on the light absorption layer.

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.