A semiconductor optical device includes a laminated structure constituted of a first compound semiconductor layer of an n type, an active layer, and a second compound semiconductor layer of a p type, the active layer including at least 3 barrier layers and well layers interposed among the barrier layers, and the semiconductor optical device satisfying Eg.sub.p-BR>Eg.sub.n-BR>Eg.sub.Well when a bandgap energy of the barrier layer adjacent to the second compound semiconductor layer is represented by Eg.sub.p-BR, a bandgap energy of the barrier layer between the well layers is represented by Eg.sub.Well, and a bandgap energy of the barrier layer adjacent to the first compound semiconductor layer is represented by Eg.sub.n-BR.

A thermal emission source capable of switching the intensity of light at a high response speed similarly to a photoelectric conversion element. A thermal emission source includes: a two-dimensional photonic crystal including a slab in which an n-layer made of an n-type semiconductor, a quantum well structure layer having a quantum well structure, and a p-layer made of a p-type semiconductor are stacked in the mentioned order in the thickness direction, wherein modified refractive index areas (air holes) whose refractive index differs from the refractive indices of the n-layer, the p-layer and the quantum well structure layer are cyclically arranged in the slab so as to resonate with a specific wavelength of light corresponding to a transition energy between the subbands in a quantum well in the quantum well structure layer; and a p-type electrode and an n-type electrode for applying, to the slab, a voltage which is negative on the side of the p-layer and positive on the side of the n-layer.

A semiconductor device includes a semiconductor layer formed of a III-V group semiconductor crystal containing As as a primary component of a V group. A V group element other than As has been introduced at a concentration of 0.02 to 5% into a V group site of the III-V group semiconductor crystal in the semiconductor layer.

The invention relates to a component (10) having a semiconductor layer sequence, which has a p-conducting semiconductor layer (1), an n-conducting semiconductor layer (2), and an active zone (3) arranged between the p-conducting semiconductor layer and the n-conducting semiconductor layer, wherein the active zone has a multiple quantum well structure, which, from the p-conducting semiconductor layer to the n-conducting semiconductor layer, has a plurality of p-side barrier layers (32p) having intermediate quantum well layers (31) and a plurality of n-side barrier layers (32n) having intermediate quantum layers (31). Recesses (4) having flanks are formed in the semiconductor layer sequence on the part of the p-conducting semiconductor layer, wherein the quantum well layers and/or the n- and p-side barrier layers extend in a manner conforming to the flanks of the recesses at least in regions. The interior barrier layers have a larger average layer thickness than the p-side barrier layers.

A semiconductor optical device includes an active layer, the active layer including a plurality of quantum well layers having gain peak wavelengths different from one another in a layering direction thereof, and a plurality of barrier layers, wherein the quantum well layers and the barrier layers are alternately layered over each other, and an n-type dopant has been added in the plurality of quantum well layers having gain peak wavelengths different from one another and in the plurality of barrier layers.

A semiconductor light emitting element has a laminated structure formed by laminating a first compound semiconductor layer, an active layer, and a second compound semiconductor layer. The semiconductor light emitting element satisfies I.sub.2>I.sub.1, where I.sub.1 is an operating current range when the temperature of the active layer is T.sub.1, and I.sub.2 is the operating current range when the temperature of the active layer is T.sub.2 (where T.sub.2>T.sub.1). The semiconductor light emitting element satisfies P.sub.2>P.sub.1, where P.sub.1 is a maximum optical output emitted when the temperature of the active layer is T.sub.1, and P.sub.2 is the maximum optical output emitted when the temperature of the active layer is T.sub.2 (where T.sub.2>T.sub.1).

A split electrode vertical cavity optical device includes an n-type ohmic contact layer, first through fifth ion implant regions, cathode and anode electrodes, first and second injector terminals, and p and n type modulation doped quantum well structures. The cathode electrode and the first and second ion implant regions are formed on the n-type ohmic contact layer. The third ion implant region is formed on the first ion implant region and contacts the p-type modulation doped QW structure. The fourth ion implant region encompasses the n-type modulation doped QW structure. The first and second injector terminals are formed on the third and fourth ion implant regions, respectively. The fifth ion implant region is formed above the n-type modulation doped QW structure and the anode electrode is formed above the fifth ion implant region.

A semiconductor device includes an n-type ohmic contact layer, cathode and anode electrodes, p-type and n-type modulation doped quantum well (QW) structures, and first and second ion implant regions. The anode electrode is formed on the first ion implant region that contacts the p-type modulation doped QW structure and the cathode electrode is formed by patterning the first and second ion implant regions and the n-type ohmic contact layer. The semiconductor device is configured to operate as at least one of a diode laser and a diode detector. As the diode laser, the semiconductor device emits photons. As the diode detector, the semiconductor device receives an input optical light and generates a photocurrent.

A Dual-wavelength hybrid (DWH) device includes an n-type ohmic contact layer, cathode and anode terminal electrodes, first and second injector terminal electrodes, p-type and n-type modulation doped QW structures, and first through sixth ion implant regions. The first injector terminal electrode is formed on the third ion implant region that contacts the p-type modulation doped QW structure and the second injector terminal electrode is formed on the fourth ion implant region that contacts the n-type modulation doped QW structure. The DWH device operates in at least one of a vertical cavity mode and a whispering gallery mode. In the vertical cavity mode, the DWH device converts an in-plane optical mode signal to a vertical optical mode signal, whereas in the whispering gallery mode the DWH device converts a vertical optical mode signal to an in-plane optical mode signal.

An nitride semiconductor device for the improvement of lower operational voltage or increased emitting output, comprises an active layer comprising quantum well layer or layers and barrier layer or layers between n-type nitride. semiconductor layers and p-type nitride semiconductor layers, wherein said quantum layer in said active layer comprises InxGa1xN (0<x<1) having a peak wavelength of 450 to 540 nm and said active layer comprises laminating layers of 9 to 13, in which at most 3 layers from the side of said n-type nitride semiconductor layers are doped with an n-type impurity selected from the group consisting of Si, Ge and Sn in a range of 510.sup.16 to 210.sup.18/cm.sup.3.