Substrate for inversely installed LED chip and manufacturing method thereof

Abstract

The invention provides a substrate for an inversely installed LED chip and a manufacturing method thereof. The substrate includes a support substrate, a dielectric layer, and a crystal lattice matching layer in the same structure with an epitaxial layer crystal structure of the inversely installed LED chip, the dielectric layer and the crystal lattice matching layer are arranged on the support substrate, the crystal lattice matching layer is in a cylinder structure arranged in an array and is embedded in the dielectric layer, or, the dielectric layer is in a cylinder structure arranged in an array and is embedded in the crystal lattice matching layer. The crystal quality of the inversely installed LED chip is improved, namely, the internal quantum efficiency is improved, the reflection of light from the epitaxial layer to the substrate can be reduced, the transmission is increased, the luminous efficiency of the inversely installed LED chip is improved, namely, the external quantum efficiency is improved.

Description

technical field [0001] The invention belongs to the field of manufacturing semiconductor optoelectronic chips, in particular to a substrate for flip-chip LED chips and a manufacturing method thereof. Background technique [0002] Since the commercialization of GaN-based LEDs in the early 1990s, after more than 20 years of development, its structure has become mature and perfect, and it has been able to meet people's current needs for lighting decoration; but it must completely replace traditional light sources and enter the lighting industry. In the field of lighting, especially in the field of high-end lighting, the improvement of luminous brightness is the never-ending pursuit of scientific researchers in the LED industry. In recent years, the most active technology in improving LED luminance is undoubtedly the patterned substrate technology. The patterned substrate technology not only improves the crystal quality of LED epitaxy by reducing lattice defects (or lattice mism...

AI Technical Summary

Problems solved by technology

However, the flip-chip LED chip structure emits light on the N side. Since the refractive index of sapphire is lower than that of gallium nitride, the light emitted from the epitaxial layer will be reflected on the interface between the sapphire and the substrate, resulting in more light. It cannot be emitted, especially the patterned substrate currently used in the mainstream of the LED chip structure has scattering and diffuse reflection effects, which is more likely to cause more light not to be emitted, reducing the light extraction efficiency

Not only that, after the patterned substrate replaces the flat substrate, the surface of the patterned substrate must be filled with a thicker buffer layer to ensure that the epitaxial layer on the substrate has a higher crystal quality. However, the buffer The layer is generally a polycrystalline material, which has a high light absorption rate, which seriously damages the light-emitting effect of the flip-chip LED chip; however, if the patterned substrate technology is not used, the internal quantum efficiency of the LED chip cannot be fully utilized.

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