A nitride light emitter includes: a nitride semiconductor light-emitting element including an Al.sub.xGa.sub.1-xN substrate (0≤x≤1) and a multilayer structure above the Al.sub.xGa.sub.1-xN substrate; and a submount substrate on which the nitride semiconductor light-emitting element is mounted. The multilayer structure includes a first clad layer of a first conductivity type, a first light guide layer, a quantum-well active layer, a second light guide layer, and a second clad layer of a second conductivity type which are stacked sequentially from the Al.sub.xGa.sub.1-xN substrate. The multilayer structure and submount substrate are opposed to each other. The submount substrate comprises diamond. The nitride semiconductor light-emitting element has a concave warp on a surface closer to the Al.sub.xGa.sub.1-xN substrate.

A nitride light emitter includes: a nitride semiconductor light-emitting element including an Al.sub.xGa.sub.1-xN substrate (0x1) and a multilayer structure above the Al.sub.xGa.sub.1-xN substrate; and a submount substrate on which the nitride semiconductor light-emitting element is mounted. The multilayer structure includes a first clad layer of a first conductivity type, a first light guide layer, a quantum-well active layer, a second light guide layer, and a second clad layer of a second conductivity type which are stacked sequentially from the Al.sub.xGa.sub.1-xN substrate. The multilayer structure and submount substrate are opposed to each other. The submount substrate comprises diamond. The nitride semiconductor light-emitting element has a concave warp on a surface closer to the Al.sub.xGa.sub.1-xN substrate.

The invention relates to an AlInGaN alloy based laser diode, which uses a gallium nitride substrate. It also includes a lower cladding layer, a lower light-guiding layer-cladding, a light emitting layer, an upper light-guiding-cladding layer, an upper cladding layer, and a subcontact layer. The lower light-guiding-cladding layer and the upper light-guiding-cladding layer have a continuous, non-step-like and smooth change of indium and/or aluminum content.

A device includes a substrate (10) and a III-nitride structure (15) grown on the substrate, the III-nitride structure comprising a light emitting layer (16) disposed between an n-type region (14) and a p-type region (18). The substrate is a RA0.sub.3 (MO).sub.n where R is one of a trivalent cation: Sc, In, Y and a lanthanide; A is one of a trivalent cation: Fe (III), Ga and Al; M is one for a divalent cation: Mg, Mn, Fe (II), Co, Cu, Zn and Cd; and n is an integer1. The substrate has an inplane lattice constant a.sub.substrate. At lease one III-nitride layer in the III-nitride structure has a bulk lattice constant a.sub.layer such that [(|a.sub.substratea.sub.layer|)/a.sub.substrate]*100% is no more than 1%.

An RAMO.sub.4 substrate that includes an RAMO.sub.4 monocrystalline substrate formed of a single crystal represented by general formula RAMO.sub.4, wherein R represents one or more trivalent elements selected from the group consisting of Sc, In, Y, and lanthanoid elements, A represents one or more trivalent elements selected from the group consisting of Fe(III), Ga, and Al, and M represents one or more divalent elements selected from the group consisting of Mg, Mn, Fe(II), Co, Cu, Zn, and Cd. The RAMO.sub.4 monocrystalline substrate has a principal surface with a plurality of grooves. The principal surface has an off-angle with respect to a cleaving surface of the single crystal. The RAMO.sub.4 monocrystalline substrate satisfies tan Wy/Wx, where Wx is the width at the top surface of a raised portion between the grooves, and Wy is the height of the raised portion.

The invention relates to an AlInGaN alloy based laser diode, which uses a gallium nitride substrate. It also includes a lower cladding layer, a lower light-guiding layer-cladding, a light emitting layer, an upper light-guiding-cladding layer, an upper cladding layer, and a subcontact layer. The lower light-guiding-cladding layer and the upper light-guiding-cladding layer have a continuous, non-step-like and smooth change of indium and/or aluminium content.

An RAMO.sub.4 substrate that includes an RAMO.sub.4 monocrystalline substrate formed of a single crystal represented by general formula RAMO.sub.4, wherein R represents one or more trivalent elements selected from the group consisting of Sc, In, Y, and lanthanoid elements, A represents one or more trivalent elements selected from the group consisting of Fe(III), Ga, and Al, and M represents one or more divalent elements selected from the group consisting of Mg, Mn, Fe(II), Co, Cu, Zn, and Cd. The RAMO.sub.4 monocrystalline substrate has a principal surface with a plurality of grooves. The principal surface has an off-angle with respect to a cleaving surface of the single crystal. The RAMO.sub.4 monocrystalline substrate satisfies tan Wy/Wx, where Wx is the width at the top surface of a raised portion between the grooves, and Wy is the height of the raised portion.

The present disclosure provides a preparation method of a polymer film laser. Polymer materials are dissolved in an organic solvent, a polymer solution is spin-coated on a substrate with or without a grating structure, and a homogeneous polymer thin film is formed. For the substrate without the grating structure, an interference pattern of an ultraviolet laser is used to interact with a thin polymer film, and one-dimensional or multi periods grating structures with multi directions are formed. The substrate with the thin polymer film is immersed in a hydrochloric acid solution or water and the polymer film with the grating structure peels off the substrate to obtain the polymer film laser. A pump beam is used to excite the polymer film to generate fluorescence, which is reflected and gained by the grating to obtain laser outputs.

The present disclosure provides a preparation method of a polymer film laser. Polymer materials are dissolved in an organic solvent, a polymer solution is spin-coated on a substrate with or without a grating structure, and a homogeneous polymer thin film is formed. For the substrate without the grating structure, an interference pattern of an ultraviolet laser is used to interact with a thin polymer film, and one-dimensional or multi periods grating structures with multi directions are formed. The substrate with the thin polymer film is immersed in a hydrochloric acid solution or water and the polymer film with the grating structure peels off the substrate to obtain the polymer film laser. A pump beam is used to excite the polymer film to generate fluorescence, which is reflected and gained by the grating to obtain laser outputs.

Bulk relaxed Wurtzite In-containing III-nitride layers having a smooth and substantially pit-free surface morphology and an interface region having a substantially relaxed in-plane a-lattice parameter and characterized by a single-phase gallium-polar (0001) orientation are disclosed. Methods of making the bulk relaxed Wurtzite In-containing III-nitride layers using MOCVD growth conditions are also disclosed. Semiconductor structures include epitaxial layers grown on a bulk relaxed Wurtzite In-containing III-nitride layer. The semiconductor structures can be used in optoelectronic devices such as in light sources for illumination and display applications.