Vertical Resonant Surface Emission Laser Structure with Quantum Well Mixing

摘要

The present invention consists of a multi-quantum well active layer and a semiconductor multilayer thin film Bragg mirror layer above and below, wherein the layer closest to the active layer among the p-type Bragg mirror layers is partially oxidized and not oxidized at the center of the cylindrical mesa. The center part forms a current path and relates to a vertical resonance surface emitting laser structure in which quantum wells are mixed only in oxidized peripheral part quantum wells. When material mixing occurs between the quantum well and the barrier layer, the energy level of the quantum well is increased, which acts as a spatial energy barrier for the part where no quantum well mixing occurs. After the process, the rapid heat treatment is performed in a high temperature nitrogen atmosphere. In this case, the co-reinforced quantum well mixing phenomenon is actively generated only in the quantum well layer in the portion facing the oxide film, and thus has a higher energy band gap than the current path, that is, the quantum well in the non-oxidized portion. In this structure, the path of injected current is limited only to the portion of the current path that is not oxidized, and the diffusion of the transporter that reaches the quantum well active layer is also limited to the current path size by the changed energy bandgap. Therefore, it is possible to drastically reduce the current loss due to the carrier diffusion that occurs in the oxide small diameter surface emitting laser of very small diameter.