Abstract: Provided is a semiconductor laser diode, including a GaAs/In P substrate and a multi-layer structure on the GaAs/InP substrate. The multi-layer structure includes a lower epitaxial region, an active region and an upper epitaxial region. The active region comprises a first active layer, an epitaxial region and a second active layer, the epitaxial region is disposed between the first active layer and the second active layer, the first active layer comprises one or more quantum well structures or one or more quantum dot structures, and the second active layer comprises one or more quantum well structures or one or more quantum dot structures.

Abstract: A vertical cavity surface-emitting laser epitaxial structure having a current spreading layer is disclosed. The vertical cavity surface-emitting laser epitaxial structure includes a substrate, a first epitaxial region on the substrate, an active region on the first epitaxial region, and a current spreading layer disposed in the first epitaxial region. The current spreading layer includes an N-type dopant, and the N-type dopant is selected from a group consisting of Si, Se, and the combination thereof. The current spreading layer does not directly contact the active region.

Abstract: Provided is a semiconductor laser diode. Although the materials used in the conventional technology can reduce the strain, the selections of materials are relatively limited and the carrier confinement ability is not good. To solve the above-mentioned problems, a phosphorus-containing semiconductor layer is provided in a laser diode. As such, it can effectively reduce the strain of the active region or the total strain of the laser diode, and improve the carrier confinement capability of the active region. Therefore, it can effectively reduce the total strain or significantly improve carrier confinement under appropriate conditions of the laser diode. In some cases, it has the aforesaid effects. The phosphorus-containing semiconductor layer is suitable for an active region with one or more active layers. Especially after the phosphorus-containing semiconductor layer is provided in the active region with multiple active layers, high temperature performance are significantly improved or enhanced.