Flip-over type light emitting diode chip and preparation method thereof

Abstract

The invention provides a preparation method of a flip-over type light emitting diode chip. The preparation method comprises the steps of: providing a substrate and forming a first semiconductor layer,a light emitting layer, a second semiconductor layer and a transparent conducting layer on the substrate in sequence; removing a part of the transparent conducting layer, the second semiconductor layer, the light emitting layer and the first semiconductor layer to form a concave part, wherein the bottom of the concave part is exposed from the first semiconductor layer; forming first metal layerson the first semiconductor layer, from which the bottom of the concave part is exposed, and the transparent conducting layer so as to define first electrodes and second electrodes of the first metal layers; forming reflection layers on the first metal layers, the side wall of the concave part and the transparent conducting layer; forming second metal layers on the first metal layers and the reflection layers so as to define first electrodes and second electrodes of the second metal layers; depositing insulating layers on the second metal layers; and depositing third metal layers on the insulating layers so as to define first electrodes and second electrodes of the third metal layers. The chip prepared by the method is high in product yield.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a method for preparing flip-chip light-emitting diode chips. Background technique [0002] In recent years, with the continuous expansion of the upstream industry, the light-emitting diode packaging industry has entered the era of meager profits. The fierce price competition and disorderly industry ecological chain have prompted the industry to demand new packaging technology, so the flip-chip light-emitting diode chip has taken advantage of the trend out. Compared with the front-mounted light-emitting diode chip, the flip-chip (Flip-chip) improves the luminous efficiency and improves the heat dissipation performance by avoiding the occupation of the light-emitting area by the electrodes in the front-mounted chip. At the same time, it also has low voltage, high brightness, high Reliability, high saturation current density and other advantages; in addition, the protection ...

AI Technical Summary

Problems solved by technology

The solder paste and surface electrodes of flip-chip light-emitting diodes are prone to mutual dissolution over time

The circuit layer material of the chip is similar to the electrode material. As the aging time increases, the solder paste fully reacts with the underlying circuit layer, and the resulting intermetallic compound gradually expands, completely lifting the passivation insulating layer covering the circuit layer. Lead to the failure of the passivation insulating layer, which in turn leads to the failure of chip leakage

[0007] In addition to the above-mentioned phenomena, there are many reasons for the leakage of flip-chip LED chips, and once the LED leaks, its light output efficiency will be greatly reduced. Therefore, improving the leakage of flip-chip LEDs has become an urgent need for the entire industry. Technical issues resolved

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