Method for manufacturing inverted LED chip

Abstract

The invention relates to a method for manufacturing an inverted LED chip. The method comprises the following steps: forming a light reflection layer on the surface of a P-type ohmic contact layer; forming an N-type electrode formation area; forming an insulating dielectric film; forming a P-type electrode area and an N-type electrode area; manufacturing a P-type electrode and an N-type electrode, wherein the N-type electrode adopts a staircase structure, the lower end of the N-type electrode penetrates the insulating dielectric film to be connected with an N-type layer, the upper end of the N-type electrode extends towards the position of the P-type electrode, and the N-type electrode at the upper end and the P-type electrode are provided with common soldering surfaces of which heights are equal or approximately equal; and the P-type electrode and the N-type electrode are fixed on the respective PCB board through soldering. As the N-type electrode and the P-type electrode of the inverted LED chip are provided with the common soldering surfaces of which heights are equal or approximately equal, the yield of packaging in the flip-chip process of the LED chip is increased, and the phenomenon of inveracious soldering or desoldering of the electrode is avoided.

Description

technical field [0001] The invention relates to a method for manufacturing an LED chip, in particular to a method for manufacturing a flip-chip LED chip. Background technique [0002] The light-emitting surface of the blue, green or violet LED chip made on the sapphire substrate is the growth surface of the epitaxial material, that is, the P-type surface. During the LED packaging process, the sapphire substrate surface is directly fixed on the heat sink. During the working process of the LED, its light-emitting area is the source of heat generation of the device. Since the sapphire substrate itself is an insulator material, and its thermal conductivity is poorer than that of GaN materials, the working current of this formally mounted LED device is limited to ensure the luminous efficiency and working life of the LED. In order to improve the heat dissipation performance of the device, people have designed an LED chip structure, that is, a flip-chip LED chip. [0003] Since...

AI Technical Summary

Problems solved by technology

[0006] 1. The N-type electrode 37 is far away from the P-type electrode 34 in the horizontal direction. The N-type electrode 37 has strict requirements on the position design of the PCB board 27 below it, which affects the packaging quality rate

[0007] 2. The position of the N-type electrode 37 is much higher than that of the P-type electrode 34, resulting in a large gap between it and the PCB board 39 below, and it is easy to make the N-level solder layer 38 too long during soldering, resulting in false soldering or detachment Occurrence of welding

[0008] 3. In order to allow welding of the N-type electrode 37 and the PCB board 39 below it, a large part of the light-emitting area needs to be removed, which affects the luminous efficiency of the LED chip

Images