Reverse-polarity AlGaInP-based LED side wall coarsening method

Abstract

The invention relates to a reverse-polarity AlGaInP-based LED side wall coarsening method. The method includes the following steps that (1) exposure and development are conducted on a mesa image epitaxial wafer of a reverse-polarity AlGaInP-based LED through an existing photolithographic process, and a constant periodicity edge figure is formed at the periphery of the mesa image epitaxial wafer; (2) the mesa image epitaxial wafer obtained after development in the step (1) is corroded through deionized water containing saturation Br2; (3) cleaning and photoresist removing are conducted on the mesa image epitaxial wafer after being corroded through the step (2) according to the conventional process, and coarsening side wall corresponding to the periodicity edge figure shape is formed. According to the reverse-polarity AlGaInP-based LED side wall coarsening method, the mode that coarsening of the side wall of the LED chip is achieved through the photolithographic technology is first proposed, the light extraction efficiency of the LED, especially the LED chip side face, is improved greatly compared with the prior art, the external quantum efficiency of LED devices is improved, internal heat is reduced, and the service life of the LED is prolonged.

Description

technical field [0001] The invention relates to a method for roughening the side wall of a reverse-polarity AlGaInP-based LED, belonging to the technical field of light-emitting diode manufacturing. Background technique [0002] In the 1950s, with the efforts of many well-known research institutions represented by IBM Thomas J. Watson Research Center, III-V semiconductors represented by GaAs rose rapidly in the field of semiconductor light emitting. Later, with the emergence of metal oxide chemical vapor deposition (MOCVD) technology, the growth of high-quality III-V semiconductors broke through the technical barrier, and semiconductor light-emitting diode devices with various wavelengths flooded into the market one after another. Compared with the current light-emitting devices, semiconductor light-emitting diodes have the characteristics of high theoretical efficiency, long life, and mechanical shock resistance, and are regarded as a new generation of lighting devices worl...

AI Technical Summary

Problems solved by technology

The disadvantages of using etching to roughen the light-emitting surface of LEDs are: (1) etching is very destructive to the carrier transport properties of semiconductor materials, which significantly reduces the electrical properties of LEDs; (2) ) The cost of purchasing and using etching equipment is extremely high, which greatly increases the cost of LEDs; (3) There is no way to control and optimize the shape and size of the roughened LED light-emitting surface by etching; (4) Processing time Longer, less productive

The shortcomings of using chemical corrosion to roughen the light-emitting surface of LEDs are: (1) It is difficult to accurately control the rate and depth of corrosion, which is determined by the inherent defects of chemical methods; (2) It is susceptible to external environmental temperature and other factors. impact, it is difficult to obtain highly repeatable roughened LED chips; (3) the structure obtained by etching is single, and it is difficult to optimize the light extraction effect

(4) The processing time is longer and the production efficiency is lower

This method has high requirements for the epitaxial growth of semiconductor materials, is not easy to realize, and is extremely difficult to control

[0011] Due to the obvious anisotropic corrosion characteristics of quaternary phosphide semiconductor materials, such as the AlGaInP base described in the present invention, it is difficult to realize the control of its side wall morphology by using the traditional mesa etching method, and it is impossible to obtain an excellent side wall corrosion profile. appearance

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