LED epitaxial wafer based on graphical Si substrate and making method of LED epitaxial wafer

The invention discloses an LED epitaxial wafer based on a graphical Si substrate and a making method of the LED epitaxial wafer. The LED epitaxial wafer comprises the graphical Si substrate, an Al2O3 coating growing on the graphical Si substrate, a nucleating layer, a first buffer layer, a first interposition layer, a second buffer layer, a second interposition layer, an n-GaN layer, an InGaN/GaN quantum well layer, a p-GaN layer, an n electrode and a p electrode, wherein the nucleating layer, the first buffer layer, the first interposition layer, the second buffer layer, the second interposition layer, the n-GaN layer, the InGaN/GaN quantum well layer and the p-GaN layer sequentially grow on the Al2O3 coating, the n electrode is electrically connected with the n-GaN layer, and the p electrode is electrically connected with the p-GaN layer. The making method is more suitable for making LED epitaxial wafers with a large size, crystal quality is improved, and light extraction efficiency of an LED tube core is improved.