Diode includes first metal layer, coupled to p-type III-N layer and to first terminal, has a substantially equal lateral size to the p-type III-N layer. Central portion of light emitting region on first side and first metal layer includes first via that is etched through p-type portion, light emitting region and first part of n-type III-N portion. Second side of central portion of light emitting region that is opposite to first side includes second via connected to first via. Second via is etched through second part of n-type portion. First via includes second metal layer coupled to intersection between first and second vias. Electrically-insulating layer is coupled to first metal layer, first via, and second metal layer. First terminals are exposed from electrically-insulating layer. Third metal layer including second terminal is coupled to n-type portion on second side of light emitting region and to second metal layer through second via.

A method of manufacturing a nitride semiconductor element includes dry etching a main surface of a sapphire substrate at a c-plane side thereof, using a mask provided on the main surface, to form a plurality of projections, each having a circular bottom surface; wet etching the sapphire substrate to form an upper part of each projection into a triangular pyramid shape while maintaining the circular bottom surface of the projection; and growing a semiconductor layer made of a nitride semiconductor on a dry etched surface and a wet etched surface of the sapphire substrate.

A contact to a semiconductor heterostructure is described. In one embodiment, there is an n-type semiconductor contact layer. A light generating structure formed over the n-type semiconductor contact layer has a set of quantum wells and barriers configured to emit or absorb target radiation. An ultraviolet transparent semiconductor layer having a non-uniform thickness is formed over the light generating structure. A p-type contact semiconductor layer having a non-uniform thickness is formed over the ultraviolet transparent semiconductor layer.

A light emitting diode includes a first electrode, a second electrode, and an epitaxial structure. The epitaxial structure is arranged on the first electrode, and electrically connects with the first electrode and the second electrode. The second electrode surrounds periphery of the epitaxial structure to reflect light from the epitaxial structure out from the top of the epitaxial structure. A method for manufacturing the light emitting diode is also presented. The light emitting diode and the method increase lighting efficiency of the light emitting diode.

Disclosed is a light emitting diode using light of a short wavelength band. The light emitting diode includes a first conductivity type semiconductor layer having a front side and a back side, a second conductivity type semiconductor layer having a front side and a back side, an active layer formed between the back side of the first conductivity type semiconductor layer and the front side of the second conductivity type semiconductor layer, a first electrode electrically connected to the first conductivity type semiconductor layer, a second conductivity type reflective layer formed on the back side of the second conductivity type semiconductor layer, and a reflective part formed on the second conductivity type reflective layer to reflect light of a short wavelength band and light of a blue wavelength band and electrically connected to the second conductivity type semiconductor layer. The second conductivity type reflective layer includes DBR unit layers. Each of the DBR unit layers includes a low refractive index layer and a high refractive index layer adjacent to the low refractive index layer. The low refractive index layer and the high refractive index layer include Al.sub.xGa.sub.1-xN (0<x1) and Al.sub.yGa.sub.1-yN (0y<1, y<x), respectively.

A light emitting element manufacturing method of allowing a semiconductor laminated part which includes a light emitting layer and includes a group-III nitride semiconductor to grow on a substrate surface in which protrusions are formed in a period which is larger than an optical wavelength of light emitted from the light emitting layer and is smaller than a coherent length of the light, includes: forming a buffer layer along the substrate surface having the protrusions; allowing crystal nuclei which have facet surfaces and are separated from each other to grow on the buffer layer such that the crystal nuclei include at least one protrusion; and allowing a planarization layer to grow on the buffer layer in which the crystal nuclei are formed.

A light emitting diode chip includes: a first conductive type semiconductor layer disposed on a substrate; a mesa disposed on the first conductive type semiconductor layer and including an active layer and a second conductive type semiconductor layer; an insulation layer covering the first conductive type semiconductor layer and the mesa, the insulation layer including at least one first opening exposing the first conductive type semiconductor layer and a second opening disposed on the mesa; a first pad electrode disposed on the insulation layer and electrically connected to the first conductive type semiconductor layer through the first opening; and a second pad electrode disposed on the insulation layer and electrically connected to the second conductive type semiconductor layer through the second opening. The first opening of the insulation layer includes a first region covered by the first pad electrode and a second region exposed outside the first pad electrode.

A light emitting device can include a GaN layer having a multilayer structure that can include an n-type layer, an active layer, and a p-type layer, the GaN layer having a first surface and a second surface; a conductive structure on the first surface of the GaN layer, the conductive structure includes a first electrode in contact with the first surface of the GaN layer, the first electrode is configured to reflect light from the active layer back through the second surface of the GaN layer; and a metal layer including Au, in which the metal layer serves as a first pad; a second electrode on the second surface of the GaN layer; and a second pad on the second electrode, in which a thickness of the second pad is about 0.5 m or higher.

A light-emitting device comprises a textured substrate comprising a plurality of textured structures, wherein the textured structures and the textured substrate are both composed of sapphire; and a light-emitting stack overlaying the textured substrate, comprising a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, wherein one of the plurality of textured structures comprises a top portion and a bottom portion, wherein a first distance between a first projection of the top portion on the bottom portion and the bottom portion at one side is different from a second distance between a second projection of the top portion on the bottom portion and the bottom portion at another side.

By controlling the luminance of light emitting element not by means of a voltage to be impressed to the TFT but by means of controlling a current that flows to the TFT in a signal line drive circuit, the current that flows to the light emitting element is held to a desired value without depending on the characteristics of the TFT. Further, a voltage of inverted bias is impressed to the light emitting element every predetermined period. Since a multiplier effect is given by the two configurations described above, it is possible to prevent the luminance from deteriorating due to a deterioration of the organic luminescent layer, and further, it is possible to maintain the current that flows to the light emitting element to a desired value without depending on the characteristics of the TFT.