Growth and Characterization of Cu(111) on Al2O3 (111) Surfaces

There exist a small lattice mismatch between Cu(111) and graphene, which makes Cu(111) the preferred substrate for graphene synthesis. It is essential to prepare a large scale Cu(111) surface before we can synthesize large-scale grapehene for device applications. In this presentation, we will report our study on the Cu(111) growth on Al2O3 (111) surfaces. A layer of 350-nm thick copper was sputtered onto sapphire pieces cut from a Al2O3 (111) wafer. We found significant twinning on the Cu(111) surfaces originated from surface defects. Annealing in a reduced ambient or depositing copper at higher temperatures promotes coalescence of the twinned regions. Investigation of reducing surface defects by different substrate surface preparation and sputtering conditions is in progress. Preliminary results of chemical vapor deposition of ethylene on the Cu(111) will also be reported