GaN-based VCSEL chip based on porous DBR and preparation method

Abstract

The invention discloses a GaN-based VCSEL chip based on a porous DBR. The GaN-based VCSEL chip comprises a substrate, a buffer layer manufactured on the substrate, a bottom porous DBR layer manufactured on the buffer layer, an n-type doped GaN layer manufactured on the bottom porous DBR layer, an active layer manufactured on the n-type doped GaN layer, an electron blocking layer manufactured on the active layer, a p-type doped GaN layer manufactured on the electron blocking layer, a current limiting layer manufactured on the p-type doped GaN layer, a transparent electrode manufactured on the p-type doped GaN layer, an n electrode, a p electrode manufactured on the transparent electrode, and a dielectric DBR layer, wherein a table board is formed by etching the periphery of the n-type doped GaN layer downwards; a current window is formed in the center of the current limiting layer; the current limiting layer covers the active layer, the electron blocking layer and the side wall of a bulge part of the n-type doped GaN layer; the n electrode is manufactured on the table board of the n-type doped GaN layer; a notch is formed in the middle of the p electrode; and the dielectric DBR layer is manufactured on the transparent electrode in the notch of the p electrode.

Description

technical field [0001] The invention belongs to the field of laser light sources, in particular to a GaN-based VCSEL (vertical cavity surface emitting laser), in particular to a GaN-based VCSEL chip based on a porous DBR bottom reflector and a preparation method. Background technique [0002] GaN semiconductor-based lasers have shown great application prospects and market demand in high-density optical storage, laser lighting, laser display, visible light communication and other fields, and have attracted much attention in international scientific research and industry in recent years. At present, GaN basal edge-emitting lasers have been commercialized, but vertical cavity surface-emitting lasers (VCSELs) with better performance have not yet reached the practical level. Compared with traditional edge-emitting lasers, GaN-based VCSELs have good dynamic single-mode and spatial emission mode characteristics, low operating threshold, small beam divergence angle, low manufacturin...

AI Technical Summary

Problems solved by technology

However, the cost of the laser lift-off method is high, and the bottom of the epitaxial layer after lift-off is very uneven, and chemical polishing is required to achieve the planarization of the lift-off surface, thereby reducing the scattering loss

In addition, in order to minimize the impact of laser lift-off on the active region, it is often necessary to use a longer resonant cavity length to keep the active region away from the peeled surface, but this will reduce the quality factor of the resonant cavity.

Therefore, the method of peeling off the substrate and depositing the dielectric DBR bottom reflector is complex and expensive, which is not ideal for practical GaN-based VCSELs.

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