Abstract: A positive active material for a rechargeable lithium battery may include a first positive active material including a lithium cobalt-based oxide doped with aluminum and coated with zirconium; and a second positive active material including a lithium cobalt-based oxide doped with aluminum and coated with zirconium, wherein a particle diameter of the second positive active is smaller than a particle diameter of the first positive active material, in the first positive active material, a doping amount of aluminum based on a total weight of the lithium cobalt-based oxide is about 0.50 wt % to about 0.80 wt %, in the second positive active material, a doping amount of aluminum based on the total weight of the lithium cobalt-based oxide is about 0.20 wt % to about 0.40 wt %, and a coating amount of zirconium based on a total weight of the positive active material is about 0.10 wt % to about 0.15 wt %.

Abstract: A positive active material for a rechargeable lithium battery includes nickel-based lithium transition metal oxide secondary particles, in which a plurality of primary particles are aggregated. The primary particles include polycrystalline primary particles composed of 2 to 10 single crystals, and each of the single crystals has a particle diameter of about 0.5 ?m to about 3 ?m.

Abstract: A positive active material for a rechargeable lithium battery includes nickel-based lithium transition metal oxide secondary particles, in which a plurality of primary particles are aggregated. The primary particles include polycrystalline primary particles composed of 2 to 10 single crystals, and each of the single crystals has a particle diameter of about 0.5 ?m to about 3 ?m.

Abstract: A light emitting device is disclosed. The light emitting device includes a light emitting structure including a first conductive-type semiconductor layer, an active layer, and a second conductive-type semiconductor layer, a light-transmissive conductive layer disposed on the second conductive-type semiconductor layer and having a plurality of open regions through which the second conductive-type semiconductor layer is exposed, and a second electrode disposed on the light-transmissive conductive layer so as to extend beyond at least one of the open regions, wherein the second electrode contacts the second conductive-type semiconductor layer in the open regions and contacts the light-transmissive conductive layer in regions excluding the open regions.

Abstract: A light-emitting device discloses a light emitting structure layer including an active layer between first and second conductive semiconductor layers, a first electrode electrically connected to the first conductive semiconductor layer, a contact layer disposed under the second conductive semiconductor layer, a reflective layer disposed under the contact layer, a capping layer disposed under the reflective layer, and a conductive supporting member disposed under the capping layer. The reflective layer comprises a thickness that is greater than the thickness of the second conductive semiconductor layer and 90 or more times greater than the thickness of the contact layer.

Abstract: A light emitting device includes a substrate, a plurality of light emitting cells disposed on the substrate to be spaced apart from each other, and a connection wire electrically connecting adjacent ones of the light emitting cells. A first separation distance between first adjacent light emitting cells that are not connected by the connection wire among the light emitting cells is smaller than a second separation distance between second adjacent light emitting cells connected by the connection wire among the light emitting cells.

Abstract: A light emitting device includes a substrate, a plurality of light emitting cells disposed on the substrate to be spaced apart from each other, and a connection wire electrically connecting adjacent ones of the light emitting cells. One of the adjacent light emitting cells includes a plurality of first segments, and the other of the adjacent light emitting cells includes a plurality of second segments respectively facing the first segments. A separation distance is provided between first and second segments facing each other, where each of which has an end contacting the connection wire is greater than a separation distance between first and second segments facing each other, and each of which has an end that does not contact the connection wire.

Abstract: A light-emitting device discloses a light emitting structure layer including an active layer between first and second conductive semiconductor layers, a first electrode electrically connected to the first conductive semiconductor layer, a contact layer disposed under the second conductive semiconductor layer, a reflective layer disposed under the contact layer, a capping layer disposed under the reflective layer, and a conductive supporting member disposed under the capping layer. The reflective layer comprises a thickness that is greater than the thickness of the second conductive semiconductor layer and 90 or more times greater than the thickness of the contact layer.

Abstract: A light emitting device includes a light emitting structure having a plurality of light emitting regions including a first semiconductor layer, an active layer, a second semiconductor layer, a first electrode in one of the light emitting regions, a second electrode in another of the light emitting regions, and at least one connection electrode to sequentially connect the light emitting regions in series. The light emitting regions connected in series are divided into 1st to ith light emitting region groups. Areas of light emitting regions that belong to different groups are different. An area of a light emitting region which is more frequently used among the plurality of light emitting regions is larger than an area of a light emitting region which is less frequently used among the plurality of light emitting regions.

Abstract: A light emitting device includes a substrate, a plurality of light emitting cells disposed on the substrate to be spaced apart from each other, and a connection wire electrically connecting adjacent ones of the light emitting cells. One of the adjacent light emitting cells includes a plurality of first segments, and the other of the adjacent light emitting cells includes a plurality of second segments respectively facing the first segments. A separation distance is provided between first and second segments facing each other, where each of which has an end contacting the connection wire is greater than a separation distance between first and second segments facing each other, and each of which has an end that does not contact the connection wire.

Abstract: A light emitting device is disclosed. The light emitting device includes a light emitting structure including a first conductive-type semiconductor layer, an active layer, and a second conductive-type semiconductor layer, a light-transmissive conductive layer disposed on the second conductive-type semiconductor layer and having a plurality of open regions through which the second conductive-type semiconductor layer is exposed, and a second electrode disposed on the light-transmissive conductive layer so as to extend beyond at least one of the open regions, wherein the second electrode contacts the second conductive-type semiconductor layer in the open regions and contacts the light-transmissive conductive layer in regions excluding the open regions.

Abstract: Provided is a light emitting device. The light emitting device includes a light emitting structure layer comprising a first conductive type semiconductor layer, an active layer, and a second conductive type semiconductor layer. A first electrode is connected to the first conductive type semiconductor layer and includes first pad, plurality of first bridge portions and plurality of first contact portions. A current spreading layer is on a top surface of the second conductive type semiconductor layer. An insulation layer is on an upper surface of the first conductive type semiconductor layer and a top surface of the current spreading layer. A second electrode is on a top surface of the current spreading layer. The plurality of first bridge portions are extended from the first pad at an acute angle to each other.

Abstract: A light emitting device includes a substrate, a plurality of light emitting cells disposed on the substrate to be spaced apart from each other, and a connection wire electrically connecting adjacent ones of the light emitting cells. One of the adjacent light emitting cells includes a plurality of first segments, and the other of the adjacent light emitting cells includes a plurality of second segments respectively facing the first segments. A separation distance is provided between first and second segments facing each other, where each of which has an end contacting the connection wire is greater than a separation distance between first and second segments facing each other, and each of which has an end that does not contact the connection wire.

Abstract: Disclosed are a light emitting device. The light emitting device includes a light emitting structure including a first conductive type semiconductor layer, an active layer, and a second conductive type semiconductor layer, a first electrode disposed in an opening portion of the light emitting structure and contacted with a portion of the first conductive type semiconductor layer, an insulating layer covering the first electrode, a second electrode disposed connected to the second conductive type semiconductor layer and first electrode layer is connected to the second conductive type semiconductor layer and the second electrode. The first electrode layer is disposed on a top surface of the second conductive type semiconductor layer and a top surface of the insulating layer. The second electrode is not vertically overlapped with the first electrode.

Abstract: A light emitting device is disclosed. The light emitting device includes a light emitting structure including a first conductive-type semiconductor layer, an active layer, and a second conductive-type semiconductor layer, a light-transmissive conductive layer disposed on the second conductive-type semiconductor layer and having a plurality of open regions through which the second conductive-type semiconductor layer is exposed, and a second electrode disposed on the light-transmissive conductive layer so as to extend beyond at least one of the open regions, wherein the second electrode contacts the second conductive-type semiconductor layer in the open regions and contacts the light-transmissive conductive layer in regions excluding the open regions.

Abstract: A light emitting device includes a light emitting structure having a plurality of light emitting regions including a first semiconductor layer, an active layer, a second semiconductor layer, a first electrode in one of the light emitting regions, a second electrode in another of the light emitting regions, and at least one connection electrode to sequentially connect the light emitting regions in series. The light emitting regions connected in series are divided into 1st to ith light emitting region groups. Areas of light emitting regions that belong to different groups are different. An area of a light emitting region which is more frequently used among the plurality of light emitting regions is larger than an area of a light emitting region which is less frequently used among the plurality of light emitting regions.

Abstract: A light emitting device including a light emitting structure comprising a plurality of light emitting regions comprising a first semiconductor layer, an active layer and a second semiconductor layer, a first electrode unit disposed on the first semiconductor layer in one of the light emitting regions, a second electrode unit disposed on the second semiconductor layer in another of the light emitting regions, and at least one connection electrode to sequentially connect the light emitting regions in series, wherein the light emitting regions connected in series are divided into 1st to ith light emitting region groups and areas of light emitting regions that belong to different groups are different (where 1<i?j, each of i and j is a natural number, and j is a last light emitting region group).

Abstract: A light emitting device package includes a body having a cavity therein and first and second recesses inside the cavity of the body. The first and second electrode layers are provided in the first and second recesses, and a light emitting device is provided on the first and second electrode layers. The first and second bumps are provided under the light emitting device and attached to the first and second recesses.

Abstract: Provided are a light emitting device, a light emitting device package, and a lighting system. The light emitting device includes a substrate, a light emitting structure layer, a second electrode, a first electrode, a contact portion, and a first electrode layer. The first electrode is disposed in the substrate from a lower part of the substrate to a lower part of a first conductive type semiconductor layer in a region under an active layer. The contact portion is wider than the first electrode and makes contact with the lower part of the first conductive type semiconductor layer. The first electrode layer is disposed under the substrate and connected to the first electrode.

Abstract: Disclosed is a light emitting device including a light emitting structure including a plurality of light emitting regions including a first semiconductor layer, an active layer and a second semiconductor layer, and a plurality of boundary regions disposed between the light emitting regions, a first electrode unit disposed on the first semiconductor layer in one of the light emitting regions, a second electrode unit disposed on the second semiconductor layer in another of the light emitting regions, at least one connection electrode to electrically connect the first semiconductor layer of one of adjacent light emitting regions to the second semiconductor layer of the other thereof, and an intermediate pad disposed on the first semiconductor layer or the second semiconductor layer in at least one of the light emitting regions, wherein the light emitting regions are connected in series through the connection electrode.