LED (light emitting diode) epitaxial wafer, LED chip, LED and manufacturing method

The invention discloses an LED (light emitting diode) epitaxial wafer, an LED chip, an LED and a manufacturing method, wherein the LED epitaxial wafer comprises a reflective layer, a substrate and an epitaxial layer, the substrate is arranged between the reflective layer and the epitaxial layer, an interface between the substrate and the epitaxial layer is provided with a hollow structure, the hollow structure is distributed in a periodic strip shape, and a dielectric material in the hollow structure is air. The LED epitaxial wafer, the LED chip, the LED and the manufacturing method have the advantages that the light emitting efficiency of the LED is effectively improved, meanwhile, the heat generating amount of the LED epitaxial wafer is effectively reduced, and the adverse effect on the manufacturing processes and the appearances of the LED epitaxial wafer, the LED chip and the LED is avoided.