A light-emitting thyristor includes a first semiconductor layer of a P type, a second semiconductor layer of an N type arranged adjacent to the first semiconductor layer; a third semiconductor layer of the P type arranged adjacent to the second semiconductor layer; and a fourth semiconductor layer of the N type arranged adjacent to the third semiconductor layer. A part of the first semiconductor layer is an active layer adjacent to the second semiconductor layer. A dopant concentration of the active layer is higher than or equal to a dopant concentration of the third semiconductor layer. A thickness of the third semiconductor layer is thinner than a thickness of the second semiconductor layer. A dopant concentration of the second semiconductor layer is lower than the dopant concentration of the third semiconductor layer.

A light-emitting diode includes a first semiconductor region having a first conductive type; a second semiconductor region having a second conductive type; and an active layer disposed between the first semiconductor region and the second semiconductor region and including phosphorus (P). The light-emitting diode has a rod shape, the second semiconductor region includes a first semiconductor layer, a second semiconductor layer, and a third semiconductor layer, which are sequentially stacked, the first semiconductor layer is disposed between the active layer and the second semiconductor layer, and the second semiconductor layer includes a compound represented by AlGaInP and satisfying Equation 1.

A semiconductor light-emitting device includes first and second semiconductor layers and a light-emitting layer provided between the first semiconductor layer and the second semiconductor layer. The first semiconductor layer includes a compound semiconductor represented by a compositional formula Al.sub.XGa.sub.1-XAs (0<X<1). The first semiconductor layer has an n-type conductivity and includes a first impurity of the n-type. The first layer further includes carbon with a lower concentration than a concentration of the first impurity, and oxygen with a lower concentration than the concentration of the first impurity. The second semiconductor layer includes a compound semiconductor represented by a compositional formula AlYGa1-YAs (0<Y<1). The second semiconductor layer has a p-type conductivity and including a second impurity of the p-type. The second semiconductor layer further includes carbon with a concentration substantially equal to the carbon concentration in the first semiconductor layer.

There is provided a semiconductor light emitting device, including: a first electrode; a substrate formed over the first electrode; a metal layer formed over the substrate; a semiconductor layer formed over the metal layer and including a light-emitting layer, a first conductivity type layer disposed at a substrate side with respect to the light-emitting layer and a second conductivity type layer disposed at an opposite side to the substrate with respect to the light-emitting layer; and a second electrode formed over the second conductivity type layer.

A unipolar-doped light emitting diode or laser diode is described. The diode includes a bottom region having an n-type layer, a top region having an n-type layer, and a middle region between the top and bottom regions having at least one material different from the top or bottom region forming two or more heterojunctions. The top and bottom regions create light emission by interband tunneling-induced photon emission. Systems including the unipolar-doped diode including LIDAR are also taught.

Embodiments of the invention include a III-nitride light emitting layer disposed between an n-type region and a p-type region, a III-nitride layer including a nanopipe defect, and a nanopipe terminating layer disposed between the III-nitride light emitting layer and the III-nitride layer comprising a nanopipe defect. The nanopipe terminates in the nanopipe terminating layer.

A light-emitting device is provided, which includes a first semiconductor structure, an active structure, a second semiconductor structure, and a first blocking layer. The first semiconductor structure has a first conductivity type. The active structure is on the first semiconductor structure and has a first dopant. The second semiconductor structure is on the active structure and has a second conductivity type different from the first conductivity type. The first blocking layer is between the second semiconductor structure and the active structure. The first blocking layer has the first dopant with a first doping concentration decreasing along a depth direction from the second semiconductor structure to the first semiconductor structure.

A micro LED display panel includes a blue LED layer, a green LED layer, and a red LED layer. The blue LED layer, the green LED layer, and the red LED layer are in a stacked formation. The blue, the green, and the red LED layers each include a plurality of micro LEDs spaced apart from each other. The composition of the layers is such that light emitted from all but the bottom layer is able to pass through transparent material in other layers before exiting the panel and being viewed.

A light source for plant cultivation includes a first light source emitting a first type of light for photosynthesis of a plant and a second light source emitting a second type of light for adjustment of phytochemicals in the plant. The first type of light has at least one peak in the visible spectrum, and the second type of light has a peak in a different wavelength band from the first light source. The second type of light has a peak in the wavelength band of about 360 nm to about 420 nm.

Disclosed in an embodiment is a semiconductor device comprising: a light-emitting structure including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer; a first electrode electrically connected to the first conductive semiconductor layer; a second electrode electrically connected to the second conductive semiconductor layer; a reflective layer disposed on the second electrode and including a first metal; and a nitride of the first metal between the second electrode and the reflective layer.