▎ 摘　　要

NOVELTY - Preparation of composite package substrate involves preparing graphene oxide solution by treating the flake graphite powder with a strong acid and an oxidizing agent, purifying, ultrasonically processing, and drying, preparing graphene oxide quantum dot (GOQDs) solution by dry cleavage of graphene oxide by chemical cutting, reducing and purifying, dispersing GOQDs into colloid to obtain a stable GOQDs composite encapsulation matrix material, coating encapsulation matrix material on the surface of the LED in the light-emitting direction, and curing. USE - Preparation of composite package substrate used for LED packaging. ADVANTAGE - The method produces composite package substrate having improved thermal stability and phosphor light emission. The package substrate effectively improves light extraction efficiency of package material, and achieves high device efficiency. The substrate ensures long-term stable luminous flux output of the LED device under high power.