GaN epilayer can be grown on sapphire substrate with a Ga 2O 3 sacrificial layer. It was employed for the epilayer transferring from sapphire substrate to Cu substrate using the chemical lift-off process application. The (-201) oriented β-Ga 2O 3 thin film was first deposited on the c-plane sapphire substrate, followed by the GaN growth via metalorganic vapor phase epitaxy under N 2 and H 2 environment in sequence. The crystal quality of GaN epilayer can be improved dramatically with the regrowth in a H 2 ambient. A GaN epilayer with an electroplated copper substrate was demonstrated using a chemical lift-off process where the Ga 2O 3 sacrificial layer can be laterally etched out with a hydrofluoric solution. It is worthy to mention that the separated sapphire substrate can be cleaned and reused for LED epitaxial growth next time. It is benefiting the cost down for the LED fabrication and Green Photonics Development.