▎ 摘　　要

NOVELTY - The epitaxial wafer has a substrate (1), a sacrificial layer (2) sequentially deposited on the substrate, a metal film layer (3), a buffer layer (5), an undoped GaN layer (6), a N-doped GaN layer (7), a multiple quantum well layer (8), an electron blocking layer (9), and a P-type doped GaN layer (10). The sacrificial layer is a graphene layer or a gallium tellurium layer. The metal film layer includes multiple metal islands on the sacrificial layer. Each of the metal islands is in contact with the sacrificial layer. A circle surrounds the cross section of the metal island and includes the smallest area has a diameter of 500-1500 nm. A gap exists between adjacent metal islands. The metal film layer is silver film layer, gold film layer, indium film layer, and aluminum film layer. USE - Gallium nitride (GaN)-based LED epitaxial wafer. ADVANTAGE - The contact area between the sacrificial layer and the GaN epitaxial layer is reduced, since the metal island covers a portion of the sacrificial layer. The dislocation defects caused by lattice mismatch and thermal mismatch between the substrate and the GaN material can be reduced or suppressed, and the dislocation defects are prevented from extending into the GaN epitaxial layer along the sacrificial layer, thus improving the crystal quality of the GaN material on the sacrificial layer. The use efficiency and service life of the LED device are improved, and the utility model has strong practicability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method of preparing GaN-based-LED epitaxial wafer. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a GaN-based LED epitaxial wafer. Substrate (1) Sacrificial layer (2) Metal film layer (3) Buffer layer (5) Undoped GaN layer (6) N-doped GaN layer (7) Multiple quantum well layer (8) Electron blocking layer (9) P-type doped GaN layer (10)