Abstract:
Disclosed is a light-emitting diode element including a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, an active layer. A first electrode is provided on a surface of the second semiconductor layer. A second electrode is provided in a second region of the principal surface of the first semiconductor layer. A conductive layer is arranged such that the conductive layer covers a third region, a fourth region, and a fifth region in the rear surface of the first semiconductor layer. In the rear surface of the first semiconductor layer, the first semiconductor layer includes a sixth region which is not covered with the conductive layer and which overlaps another part of the first electrode. The first semiconductor layer is not provided with a through electrode.
Abstract:
Disclosed herein is an electrode for energy devices such as electric double layer capacitors, which includes conductive fibers made of carbon, such as carbon nanotubes, as an electrode active material and has a high capacitance. The electrode for energy devices includes a current collector and a plurality of conductive fibers (e.g., carbon nanotubes) provided to stand on a surface of the current collector so that their one ends are electrically connected to the surface of the current collector, wherein the conductive fibers are made of carbon and have carboxyl group-containing functional groups or oxo group-containing functional groups and hydroxyl group-containing functional groups attached thereto. The conductive fibers preferably carry a quinone group-containing compound.