▎ 摘　　要

NOVELTY - Direct epitaxial method of graphene by chemical vapor deposition (CVD) using II-VI semiconductor zinc oxide (ZnO) substrate comprises injection molding and pre-processing ZnO substrate, adjusting growth pressure, flow rate and temperature, and directly growing graphene on ZnO. USE - The graphene-ZnO composite is used for piezoelectric device (claimed). ADVANTAGE - The method does not need metal as catalyst. There is no need to transfer graphene from the substrate since the composite can be readily used. The composite improves the electrical characteristics and reliability of the device. DETAILED DESCRIPTION - Direct epitaxial method of graphene by CVD using II-VI semiconductor zinc oxide (ZnO) substrate comprises: (A) orderly adding acetone, ethanol and deionized water in ZnO substrate to wash for 5 minutes each, taking out, and drying using high-purity nitrogen; (B) putting ZnO substrate in CVD reaction chamber and setting vacuum at 10-5-10-6 torrs to remove residual gases; (C) introducing high-purity argon (Ar) gas at 150-250 degrees C and 10-5-10-6 torrs for 10-30 minutes to adsorb gas on the surface of substrate; (D) introducing hydrogen (H2)gas for pre-processing the surface of substrate; (E) introducing H2 and methane (CH4) gas and naturally cooling without changing the flow rates of H2 and CH4, and growing graphene; and (G) reducing temperature to less than 100 degrees C, stopping introduction of Ar, H2, and CH4, and taking out graphene-ZnO composite.