Low-temperature fabrication of nanographene on a copper substrate using pentacene

Abstract

We developed a low-temperature fabrication method for nanographene on a copper (Cu) substrate. This process is called hot-mesh deposition (HMD) and uses pentacene, H2, and a tungsten (W) mesh. In HMD, pentacene and H2 molecules decompose on a heated W mesh placed between a pentacene source in a molybdenum boat and a Cu substrate. A clean surface was obtained using atomic hydrogen treatment prior to nanocarbon film formation. The nanocarbon films consisted of nanographenes, which formed on the cleaned Cu substrate. The peaks due to the D and D' bands of nanographene were observed in the Raman spectrum. It was found that nanographene could be produced by HMD even at temperatures as low as 250 °C. It is considered that the key factors for the low-temperature formation of nanographene are a clean Cu surface, and the reaction of pentacene with the 6,13-dihydropentacene generated on the heated W mesh.