▎ 摘　　要

The deposition of dielectric materials onto graphene without introducing atomic defects is challenging owing to the unavoidable exposure of carbon-carbon bonds to plasma, energetic ions, or high-energy photons that are present during deposition. Here, we report a simple and nondegradative method of depositing a silicon oxide layer on graphene based on the thermal evaporation of silicon monoxide (SiO). Raman spectroscopy and mapping showed that this method does not form defects in graphene, whereas depositing silicon oxide by e-beam evaporation severely damages graphene. The SiO-coated graphene also showed excellent resistance to ozone and hot air. Since SiO is transparent to visible light and infrared light, the coating may serve as a protective layer for graphene optical devices such as photodetectors and electro-optic modulators. Also noted that the present method is much simpler than atomic layer deposition, which requires additional functionalization of graphene. (C) 2013 The Japan Society of Applied Physics