▎ 摘　　要

NOVELTY - A metal film containing nickel or cobalt is provided on a substrate. The resultant substrate is subjected to primary heat treatment under hydrogen gas atmosphere and recrystallized to form epitaxial metal film on the substrate. The resultant substrate is subjected to secondary heat treatment under mixed gas containing methane gas and hydrogen gas atmosphere to obtain graphene film on substrate. The substrate is sapphire substrate. USE - Formation of graphene film used for electronic devices. ADVANTAGE - The method provides high-quality graphene film. DESCRIPTION OF DRAWING(S) - The drawing shows the block diagram of formation of graphene film. (Drawing includes non-English language text).