A light-emitting device is provided. The light-emitting device comprises: a substrate; and multiple radiation emitting regions arranged on the substrate, and comprising: a first radiation emitting region capable of emitting coherent light and emits a coherent light when driven by a first current; a second radiation emitting region capable of emitting coherent light and emits an incoherent light when driven by the first current, wherein each of the first radiation emitting region and the second emitting region comprises epitaxial structure comprising a first DBR stack, a light-emitting structure, and a second DBR stack.

An RAMO.sub.4 substrate including a single crystal represented by a general formula RAMO.sub.4, wherein R represents one or more trivalent elements selected from a group consisting of Sc, In, Y, and lanthanide elements, A represents one or more trivalent elements selected from a 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, in which a main plane of the RAMO.sub.4 substrate has an off-angle a tilted a with respect to an M-axis direction from a C-plane and 0.05|a|0.8 is satisfied.

A method for soldering electronic components includes providing a circuit substrate; providing a plurality of electronic components; placing the plurality of electronic components onto the circuit substrate; applying a conductor between the plurality of electronic components and the circuit substrate; providing an energy source which projects an energy beam with a first coverage; enlarging the energy beam and projecting the energy beam onto the circuit substrate with a second coverage; and melting the conductor within the second coverage via the energy beam and fixing the corresponding electronic components on the circuit substrate through the melted conductor. Besides, a method for manufacturing a LED display is disclosed.

A light-emitting device is provided. The light-emitting device comprises: a substrate; and multiple radiation emitting regions arranged on the substrate, and comprising: a first radiation emitting region capable of emitting coherent light and emits a coherent light when driven by a first current; a second radiation emitting region capable of emitting coherent light and emits an incoherent light when driven by the first current, wherein each of the first radiation emitting region and the second emitting region comprises epitaxial structure comprising a first DBR stack, a light-emitting structure, and a second DBR stack.

An RAMO.sub.4 substrate including a single crystal represented by a general formula RAMO.sub.4, wherein R represents one or more trivalent elements selected from a group consisting of Sc, In, Y, and lanthanide elements, A represents one or more trivalent elements selected from a 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, in which a main plane of the RAMO.sub.4 substrate has an off-angle a tilted a with respect to an M-axis direction from a C-plane and 0.05|a|0.8 is satisfied.

A light-emitting device is provided. The light-emitting device comprises: an epitaxial structure comprising a first DBR stack, a light-emitting stack and a second DBR stack and a contact layer in sequence; an electrode on the epitaxial structure; a current blocking layer between the contact layer and the electrode; a first opening formed in the current blocking layer; and a second opening formed in the electrode and within the first opening; wherein a part of the electrode fills in the first opening and contacts the contact layer.

Quantum cascade (QC) lasers and methods of fabricating such QC lasers are provided. The QC lasers incorporate a DFB grating without requiring the use of relying on epitaxial regrowth processes. The DFB gratings are formed as sidewall gratings along the lateral length of the QC active region, or the DFB gratings are formed atop the lateral length of the QC active region, and wherein the top DFB grating is planarized with a polymeric material.

A light-emitting device is provided. The light-emitting device comprises: an epitaxial structure comprising a first DBR stack, a light-emitting stack and a second DBR stack and a contact layer in sequence; an electrode on the epitaxial structure; a current blocking layer between the contact layer and the electrode; a first opening formed in the current blocking layer; and a second opening formed in the electrode and within the first opening; wherein a part of the electrode fills in the first opening and contacts the contact layer.

In a distributed feedback semiconductor laser element, a multi-layered structure includes a GaN substrate, an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, and a ridge waveguide is formed. A first diffraction grating is formed adjacent to and on both sides of the ridge waveguide. A depth d of a groove of the first diffraction grating is included in the range of 50 nm d200 nm, and a duty ratio duty is included in the range of an inequality (1) using constants a, b, c, and n defined for the order of the diffracted light.

[00001]$\begin{array}{cc}-\sqrt[n]{\frac{d-c}{a}}+b\mathrm{duty}\sqrt[n]{\frac{d-c}{a}}+b& \left(1\right)\end{array}$

A light-emitting device is provided. The light-emitting device is configured to emit a radiation and comprises: a substrate; an epitaxial structure on the substrate and comprising a first DBR stack, a light-emitting stack and a second DBR stack and a contact layer in sequence; an electrode; a current blocking layer between the contact layer and the electrode; a first opening formed in the current blocking layer; and a second opening formed in the electrode and within the first opening; wherein a part of the electrode fills in the first opening and contacts the contact layer; and the light-emitting device is devoid of an oxidized layer and an ion implanted layer in the second DBR stack.