High-light-efficiency spot-evening LED chip with sapphire substrate and preparation method of LED chip

Abstract

The invention provides a high-light-efficiency spot-evening LED chip with a sapphire substrate and a preparation method of the LED chip. The LED chip comprises a sapphire substrate layer, an N-type GaN layer, a multiple-quantum-well luminous layer, a P-type GaN layer and a current expanding layer from the top down sequentially, wherein inner concave micro-lens structures are formed in the sapphire substrate layer. The preparation method comprises the following steps: (1) growing the N-type GaN layer, the multiple-quantum-well luminous layer and the P-type GaN layer on the sapphire substrate sequentially; (2) forming the inner concave micro-lens structures in a surface of the sapphire substrate layer via femto-second laser pulse shock; (3) conducting chemical etching on the inner concave micro-lens structures; (4) preparing the current expanding layer on the P-type GaN layer on an epilayer; and (5) conducting electrode etching on a wafer from the current expanding layer to the N-type GaN layer, and preparing a P metal electrode and an N metal electrode on a P electrode table surface and an N electrode table surface respectively. The LED chip prepared according to the preparation method has the advantages that the light extraction efficiency is remarkably improved; the light-emitting angle is expanded; and the beams emitted by an LED are evened.

Description

technical field [0001] The invention relates to an LED chip structure with a high light efficiency and uniform spot sapphire substrate and a preparation method thereof, belonging to the technical field of LED lighting. Background technique [0002] The emergence of LED is a revolution for traditional light sources. LED is called the fourth generation lighting source or green light source. It has the characteristics of energy saving, environmental protection, long life and small size. It is widely used in various indications, displays, decorations, backlights , general lighting and urban night scenes and other fields. At present, the LED application market has broad prospects. LED products are mainly used in the three major fields of backlight, color screen and indoor lighting. With the continuous development of the industry, technological breakthroughs, and vigorous promotion of applications, the luminous efficacy of LEDs is also continuously improving, but at the same time...

AI Technical Summary

Problems solved by technology

[0007] Aiming at the problem that the luminous efficiency of the existing LED chip is still not high enough and the distribution of the emitted light spot is uneven after packaging, the present invention provides a sapphire substrate LED chip with high light efficiency and uniform spot, and also provides a preparation method of the LED chip

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