Gallium nitride-based light-emitting diode (LED) with distributed Bragg reflectors on side walls and preparation method thereof

Abstract

The invention discloses a gallium nitride-based light-emitting diode (LED) with distributed Bragg reflectors on side walls and a preparation method thereof. The preparation method comprises the following steps of: sequentially growing a N-GaN layer, a multiple-quantum well layer and a P-GaN layer on a sapphire substrate; forming a transparent conducting layer on the P-GaN layer; etching part of a table top on which the transparent conducting layer is positioned by a light shield until the N-GaN layer is exposed; forming a P electrode on the transparent conducting layer; forming a N electrode on the exposed N-GaN layer; forming the distributed Bragg reflectors on the side walls of the sapphire substrate, the N-GaN layer, the multiple quantum well layer and the P-GaN layer; and thinning and polishing the sapphire substrate, and cutting the sapphire substrate into independent LED core grains. Compared with the prior art, the invention has the advantage that the distributed Bragg reflectors with excellent reflectivity are arranged on the side walls of an LED chip, thus when light reaches the side surfaces of the sapphire substrate, light output or light extraction can be effectively increased, and the external quantum efficiency of the LED can be effectively improved.

Description

technical field [0001] The invention relates to a gallium nitride-based light-emitting diode, in particular to a gallium-nitride-based light-emitting diode with a distributed Bragg reflector on the side wall and a preparation method thereof. Background technique [0002] Light Emitting Diode (English for Light Emitting Diode, referred to as LED) has the advantages of no pollution, high brightness, low power consumption, long life, low working voltage, and easy miniaturization. As the efficiency of power GaN-based LEDs continues to increase, it will become an unstoppable trend to replace existing lighting sources with GaN-based LED semiconductor lamps; however, there are still many problems to be solved if semiconductor lighting is to enter thousands of households. The problem is luminous efficiency and production cost. [0003] Existing methods to improve LED luminous efficiency mainly include the use of graphic substrates, transparent substrates, distributed Bragg reflecto...

AI Technical Summary

Problems solved by technology

When light is emitted from the quantum well layer 13, this structure is likely to make it impossible to effectively extract the light emitted from the side wall, that is, it does not emit light upward, which affects the light extraction efficiency of the light-emitting diode.

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