LED chip

Abstract

The invention relates to an LED chip. The LED chip adopts the structure that an N-type electrode (22) adopts a staircase structure; the lower end of the N-type electrode (22) penetrates an insulating dielectric film (13) to be connected with an N-type layer (3); the middle part of the N-type electrode (22) is attached to the insulating dielectric film (13) at a vertical part; the upper end of the N-type electrode (22) is positioned above the insulating dielectric film (13) at the top, and extends towards the position of a P-type electrode (21); and the upper end of the N-type electrode (22) is connected with a second PCB board (23), and the N-type electrode (22) at the upper end and the P-type electrode (21) are provided with common soldering surfaces of which heights are equal or approximately equal. As the N-type electrode and the P-type electrode of the flip LED chip are provided with the common soldering surfaces of which heights are equal or approximately equal, the yield of packaging in the inverted-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 an LED chip, in particular to an LED chip with a flip-chip structure. 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 the flip chip design was proposed, ...

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

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