Inversion LED chip and ohmic contact electrode structure of inversion LED chip

Abstract

The invention discloses an ohmic contact electrode structure of an inversion LED chip and the inversion LED chip comprising the ohmic contact electrode structure. The inversion LED chip comprises a sapphire substrate, an N-type semiconductor layer and a P-type semiconductor layer, wherein the N-type semiconductor layer is arranged on the lower side of the sapphire substrate, the P-type semiconductor layer is arranged on the lower side of the N-type semiconductor layer, a P-type ohmic contact electrode layer wraps the lower side of the P-type semiconductor layer, the P-type semiconductor layer and the P-type ohmic contact electrode layer are provided with long-strip grooves, the grooves extend from the bottom face of the P-type ohmic contact electrode layer to the N-type semiconductor layer, and a part, located inside the grooves in the lower side, of the N-type semiconductor is provided with N-type ohmic contact electrodes which are distributed along the grooves in a long-strip shape mode. The long-strip shaped ohmic contact electrodes are designed to enable the LED chip to carry out soldering packaging. Compared with eutectic soldering, the inversion LED chip is lower in cost. Currents between the P-type semiconductor layer and the N-type semiconductor layer of the inversion LED chip are distributed evenly, and the light-emitting efficiency of the chip is improved.

Description

technical field [0001] The invention belongs to the field of optoelectronic technology, and in particular relates to an ohmic contact electrode structure of a flip-chip LED chip and a flip-chip LED chip containing the structure. Background technique [0002] Compared with regular LED chips, flip-chip LED chips have better heat dissipation function and luminous efficiency, and have the advantages of low voltage, high brightness, high reliability, high saturation current density, etc., and have greater advantages in performance. , has a good development prospect. [0003] At present, the packaging of flip-chip LED chips first prepares a flip-chip LED chip suitable for eutectic welding, and at the same time prepares a silicon substrate of a corresponding size, and makes a gold conductive layer and a lead-out conductive layer (ultrasonic gold wire) of the eutectic welding electrode on it. ball solder joint). Then, use eutectic welding equipment to weld the flip-chip LED chip a...

AI Technical Summary

Problems solved by technology

[0006] However, the existing flip-chip LED chips cannot be directly soldered with tin alloys, and there are mainly the following technical problems: since the N-type ohmic contact electrodes of the existing flip-chip LED chips are composed of several point-shaped electrodes made by sinking holes, The welding surface of each electrode is very small to be suitable for eutectic welding, and the weight of the LED chip is very light, so it cannot be soldered effectively; each N-type ohmic contact electrode is independent of each other, and it is impossible to connect each electrode, and it is connected uniformly To the welding electrode; the N-type ohmic contact electrode is dot-shaped, and the distance between each electrode and the P-type metal electrode is not equal, resulting in uneven current distribution on the N-type semiconductor, which affects the efficiency of light emission

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