Preparation method of GaN-based porous DBR

Abstract

The invention discloses a preparation method of a GaN-based porous DBR. The method comprises the following steps of (1) sequentially growing a buffer layer, an n-type GaN conductive layer, n-type high-doped layers and non-doped layers on a substrate, wherein the n-type high-doped layers and the non-doped layers are alternately stacked to form a multi-period nitride epitaxial structure; (2) depositing an insulating dielectric layer on the upper surface of the nitride epitaxial structure; (3) forming an electrode window in one side of the upper surface of the insulated dielectric layer through photolithography and corrosion, and forming a groove in the area except for an electrode window; (4) etching the electrode window downwards by adopting a dry etching technology to form an electrode table and etching a groove downwards to expose the side wall of the nitride epitaxial structure to form a corrosion groove; and (5) carrying out electrochemical corrosion on the nitride epitaxial structure of which the side wall is exposed to form a periodical porous DBR; and (6) removing the insulated dielectric layer by employing wet corrosion and completing preparation.

Description

technical field [0001] The invention belongs to the technical field of manufacturing nitride optoelectronic devices, and in particular relates to a preparation method of a GaN-based porous DBR. Background technique [0002] In the field of nitride optoelectronic device manufacturing technology, highly reflective GaN-based DBR (Distributed BraggReflector, distributed Bragg reflector) has shown great promise in high-brightness LEDs, resonant cavity enhanced LEDs (RCLEDs), vertical cavity surface emitting lasers (VCSELs) and detectors. A huge application prospect and market demand. However, for traditional GaN-based DBRs, such as epitaxial nitride DBRs represented by AlN / GaN systems, due to the lattice mismatch and thermal expansion coefficient difference of AlN / GaN, it is extremely difficult to prepare high-quality AlN / GaN-based DBRs in the actual process. big. At the same time, due to the small refractive index difference of AlN / GaN, it is often necessary to increase the nu...

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 device process is complicated and difficult to popularize by peeling off the substrate and re-depositing the dielectric DBR bottom mirror.

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