High Power Opto, Inc.

Yea-Chen Lee

Liang-Jyi Yan

Chih-Sung Chang

Chang-Han Chiang

The present invention discloses a high-reflectivity and low-defect density LED structure. A patterned dielectric layer is embedded in a sapphire substrate via semiconductor processes, such as etching and deposition. The dielectric layer is formed of two materials which are alternately stacked and have different refractive indexes. An N-type semiconductor layer, an activation layer and a light emitting layer which is a P-type semiconductor layer are sequentially formed on the sapphire substrate. An N-type electrode and a P-type electrode are respectively coated on the N-type semiconductor layer and the P-type semiconductor layer. The dielectric layer can lower the defect density of the light emitting layer during the epitaxial growth process. Further, the dielectric layer can function as a high-reflectivity area to reflect light generated by the light emitting layer and the light is projected downward to be emitted from the top or the lateral. Thereby is greatly increased the light-extraction efficiency.

High-reflectivity and low-defect density LED structure

The present invention discloses a high light-extraction efficiency LED structure, wherein metallic pads and metallic mesh wires made of an aluminum-silver alloy are formed on an LED, whereby the high-reflectivity aluminum-silver alloy makes the light incident on the metallic pads and metallic mesh wires reflected once more or repeatedly and then emitted from the surface or lateral side of the LED, wherefore the present invention can decrease the light loss and increase the light-extraction efficiency.

High light-extraction efficiency light-emitting diode structure

The present invention discloses an LED-laser lift-off method, which applies to lift off a transient substrate from an epitaxial layer grown on the transient substrate after a support substrate having an adhesion metal layer is bonded to the epitaxial layer. Firstly, the epitaxial layer is etched to define separation channels around each chip section, and the epitaxial layer between two separation channels is not etched but preserved to form a separation zone. Each laser illumination area only covers one illuminated chip section, the separation channels surrounding the illuminated chip section, and the separation zones surrounding the illuminated chip section. Thus, the adhesion metal layer on the separation channels is only heated once. Further, the outward stress generated by the illuminated chip section is counterbalanced by the outward stress generated by the illuminated separation zones, and the stress-induced structural damage on the chip section is reduced.

Growing community of inventors

Hsinchu County, Taiwan

Yea-Chen Lee