Flat FCB (Flip Chip Bonding) GaN-based LED (Light-Emitting Diode) chip structure

Abstract

The invention provides a flat FCB (Flip Chip Bonding) GaN-based LED (Light-Emitting Diode) chip structure comprising a substrate. An N-type GaN layer, a QW (Quantum Well) active area, a P-type GaN layer, a current extension level and a light-reflecting layer are sequentially arranged below the substrate from top to bottom, a stepped surface to the N-type GaN layer is etched on the light-reflecting layer, an N electrode is made on the N-type GaN layer of the stepped surface, a P electrode is made on the light-reflecting layer and arranged on the same plane with the outer end of the P electrode, a transparent insulated medium film is coated on the plane of the P electrode bonding pad and the N electrode bonding pad except the regions of P electrode bonding pad and the N electrode bonding pad, a P bonding board is made at the outer end of the P electrode bonding spot, an N bonding board is made at the outer end of the bonding point of the N electrode, and the P bonding board and the N bonding board are bonded on a P electrode area and an N electrode area of a conductive Si or SiC substrate by cocrystallization or alloy. The insulated medium film is coated outside the PN bonding pads to prevent PN from being subjected to short circuits and a limit N-area electrode conductive flat is spliced to the P area desk.

Description

Technical field [0001] The invention relates to a GaN-based blue LED (light emitting diode) structure, which belongs to the technical field of light emitting diode structures. Background technique [0002] The structure of the traditional sapphire substrate GaN-based LED (light emitting diode) chip is as follows figure 1 As shown, an N-type GaN layer 2, a quantum well QW active region 3, a P-type GaN layer 4, and a current spreading layer 5 are arranged from bottom to top on the substrate 1, and an N electrode is arranged on the N-type GaN layer 2. 7. The electrode is just on the light-emitting surface of the chip. In this structure, a small portion of the P-type GaN layer 4 and the "light emitting" layer are etched to form electrical contact with the N-type GaN layer 2 below. Light is taken out from the upper P-type GaN layer 4. The limited conductivity of the P-type GaN layer 4 requires that another layer of current diffusion layer 5 be deposited on its surface. If the curr...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the problem that the heat-conducting metal bumps in the flip-chip structure are limited, and the bumps are too large to easily cause the PN short circuit of the chip, the invention proposes a flat flip-chip GaN-based LED chip with good heat dissipation effect and flat metal pads structure

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