Gallium Nitride-based UV Lasers with Alinn Magnesium Backdiffusion Barriers

Abstract

A gallium nitride-based ultraviolet laser with an AlInN magnesium reverse diffusion barrier layer includes a gallium nitride homogeneous substrate; an n-type homoepitaxial layer; an n-type confinement layer; an n-type waveguide layer; an active region; an AlInN magnesium backdiffusion barrier layer; a p-type electron barrier layer; a p-type waveguide layer; a p-type confinement layer, which is made on the p-type waveguide layer, and the middle of the p-type confinement layer is a protrusion ridge shape; a p-type doped / p-type heavily doped contact layer, which is fabricated on the raised ridge shape of the p-type confinement layer; a p-type ohmic electrode and an n-type ohmic electrode. The invention keeps the p-type doping region away from the quantum well active region, reduces the diffusion length of magnesium impurities, increases the optical confinement factor, and reduces the threshold value of the laser.

Description

technical field [0001] The invention relates to the field of semiconductor optoelectronic devices, in particular to a gallium nitride-based ultraviolet laser with an AlInN magnesium reverse diffusion barrier layer. Background technique [0002] For GaN-based semiconductor lasers, the p-type dopant material is one of the key factors affecting the characteristics of the laser. At present, p-type doping impurities are mainly magnesium (Magnesium, Mg). After epitaxial growth, rapid thermal annealing technology is used to inhibit the passivation of hydrogen impurities on magnesium during the growth process, activate magnesium impurities, and obtain p-type with low resistivity. Material. [0003] The p-type doped materials of GaN-based lasers include GaN, AlGaN, InGaN and their composite structures. In the laser structure, common p-type doping materials include p-type AlGaN electron blocking layer, p-type GaN / AlGaN / InGaN waveguide layer, p-type AlGaN confinement layer and p-type...

AI Technical Summary

Problems solved by technology

Therefore, in the process of epitaxially growing a thicker p-type AlGaN confinement layer, the long-term high-temperature growth process causes thermal degradation of the InGaN quantum well, which reduces the quantum efficiency of the active region.

[0006] 3. Magnesium impurities in p-type doped materials have reverse diffusion characteristics, which reduces the luminous recombination efficiency of the quantum well active region

At the same time, in order to protect the InGaN quantum well grown at low temperature, the growth temperature of the AlGaN barrier layer needs to be greatly reduced, the material quality of the AlGaN barrier layer is reduced, and the defect density is increased.

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