▎ 摘　　要

NOVELTY - A metal precursor compound is dissolved in a low boiling point solvent to obtain a metal precursor solution. The metal precursor solution is subjected to ultrasonic treatment, and metal oxide precursor droplets are dispersed in a solvent. Droplets and graphene are supplied to a chamber, and droplet is adsorbed on graphene with carrier gas to form metal oxide thin film on graphene. USE - Formation of metal oxide thin film on graphene for device e.g. transparent energy electric power generating element, transparent photoelectric device or inverted organic solar cell (all claimed). ADVANTAGE - The metal oxide thin film is formed on graphene at low temperature with high crystallization without damaging graphene.