Flip LED chip and manufacturing method thereof

Abstract

The invention discloses a flip LED chip and a manufacturing method of the flip LED chip. The flip LED chip comprises a front-end structure with a substrate, an N-type gallium nitride layer, a quantum well layer and a P-type gallium nitride layer, and the N-type gallium nitride layer, the quantum well layer and the P-type gallium nitride layer are formed on the substrate. An Ohmic contact layer, a mirror medium layer and a mirror metal layer are formed on the front-end structure, and a first electrode connected with the N-type gallium nitride layer and a second electrode connected with the mirror metal layer are formed. In the flip LED chip, incoming light outside the full reflecting angle of gallium nitride and the mirror medium layer can be fully reflected, the absorption proportion of a mirror on light is reduced, meanwhile, the average reflecting rate of the full incident angle of the mirror is improved, the light emitting efficiency of the chip is improved, and the photoelectric conversion efficiency of the LED chip is improved.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a flip-chip LED chip and a manufacturing method thereof. Background technique [0002] For traditional front-mounted LED chips, P-type GaN is difficult to dope, resulting in low hole carrier concentration and difficulty in growing thick, resulting in difficult diffusion of current. At present, the method of preparing ultra-thin metal film or ITO film on the surface of P-type GaN is generally used to achieve The current has to spread evenly. However, the metal thin film electrode layer has to absorb part of the light to reduce the light extraction efficiency, and if the thickness is reduced, it will in turn limit the current diffusion layer to achieve uniform and reliable current diffusion on the surface of the P-type GaN layer. Although the light transmittance of ITO is as high as 90%, the electrical conductivity is not as good as that of metal, and the diffusion effect o...

AI Technical Summary

Problems solved by technology

[0004] At present, the light-emitting layer added between the PN junction and the P electrode of the flip-chip LED chip is a metal structure, which relies on the high reflectivity of Ag, Al, Rh and other metals to complete the reflection of the light emitted by the quantum well layer to the bottom of the chip. Metal reflection There are many disadvantages: there are different degrees of light absorption for each light incident angle, and there are limits to reflectivity, such as mirror reflectivity below 90%

Therefore, it still restricts the quality of flip-chip LED chips

Images