▎ 摘　　要

NOVELTY - A silicon nitride (Si3N4) substrate is produced by immersing Si substrate in acid solution, treating with acid to induce hydrolysis reaction while causing hydroxy (-OH) group to be formed on the surface of the substrate, forming a solution in which graphene oxide is dispersed by adding graphene oxide powder to a solvent, coating graphene oxide by drying solution on which graphene oxide is dispersed on surface of Si3N4 substrate formed with -OH group, and heat-reducing Si3N4 substrate coated with graphene oxide to change graphene oxide to graphene and obtain graphene-coated Si3N4 substrate. USE - Production of silicon nitride substrate. ADVANTAGE - Hydroxy (-OH) groups that form chemical bonds on the Si3N4 substrate are formed, so adhesion between Si3N4 substrate and graphene coating layer can be improved, where graphene coating layer formed on the substrate can effectively heat transfer by increasing thermal diffusion, and thermal conductivity characteristics can also be improved. As a result, Si3N4 substrate has excellent heat dissipation properties.