\textbf{A single}\textbf{-}\textbf{step growth process of graphane using hydrogen plasma and observation of an induced bandgap.}

There has been considerable interest in reliably opening up a bandgap in graphene for electronic applications. One promising method is the hydrogenation of graphene into graphane. We present Raman spectroscopy, scanning tunneling microscopy/spectroscopy (STM/STS) and x-ray photoemission spectroscopy (XPS) studies of hydrogenated multilayer graphene on Cu as a function of hydrogen exposure time ($t)$. Our growth process for hydrogenated graphene involved \textit{in-situ} exposure of PECVD-grown graphene on Cu to hydrogen plasma. Raman measurements revealed an increase in intensity of a pronounced and narrow D-band with $t$ when compared to pristine graphene. FTIR studies revealed the presence of C-H bonds on the surface of our samples post hydrogenation. STM topographic studies revealed a nanoscale Moir\'{e} pattern resulting from the hydrogenated graphene. For $t \quad =$ 120s, STS studies revealed an average gap of $\Delta $ \textasciitilde (0.275\textpm 0.050) eV, which increased to average value of $\Delta $ \textasciitilde (0.315\textpm 0.050) eV for $t \quad =$ 600s. Topographic and spectroscopic studies showed approximate hydrogen coverage of 20{\%}, 50{\%} and 80{\%} for $t \quad =$ 30s, 60s and 120s, respectively. XPS studies of the C-1s state revealed an energy shift from the C-C peak (284.6 nm) towards a C-H peak (285.8 nm), consistent with the formation of carbon-hydrogen bonds. Our results have demonstrated the existence of a bandgap opening in graphene, induced by the adsorption of atomic hydrogen onto graphene.