LED chip based on alumina-silica composite substrate and fabrication method thereof

An LED chip based on an alumina-silica composite substrate, comprising:

• an alumina-silica composite patterned sapphire substrate (PSS) substrate, a composite buffer layer and an LED structural layer, wherein the composite buffer layer is epitaxially grown on the alumina-silica composite PSS substrate, and the LED structural layer is epitaxially grown on the composite buffer layer;
• the composite buffer layer comprises:
• an aluminum oxynitride/aluminum nitride layer and a silicon oxynitride layer;
• the alumina in the alumina-silica composite PSS substrate is covered with the aluminum oxynitride/aluminum nitride layer, and the silica in the alumina-silica composite PSS substrate is covered with the aluminum oxynitride/aluminum nitride layer and the silicon oxynitride layer in a staggered manner;
• the aluminum oxynitride in the aluminum oxynitride/aluminum nitride layer is connected to the alumina-silica composite PSS substrate, and the aluminum nitride in the aluminum oxynitride/aluminum nitride layer is connected to the LED structural layer.