AVS 60th International Symposium and Exhibition
    Surface Science Monday Sessions
       Session SS+AS+NS-MoM

Paper SS+AS+NS-MoM11
Nucleation of Copper Islands on Graphite

Monday, October 28, 2013, 11:40 am, Room 201 A

Session: Nanostructures: Growth & Characterization
Presenter: D. Appy, Ames Laboratory, Iowa State University
Authors: D. Appy, Ames Laboratory, Iowa State University
H. Lei, Ames Laboratory, Iowa State University
C.Z. Wang, Ames Laboratory, Iowa State University
D. Shao, Ames Laboratory, Iowa State University
E. Kwolek, Ames Laboratory, Iowa State University
P.A. Thiel, Ames Laboratory, Iowa State University
Correspondent: Click to Email
Graphite, and surface processes on graphite, serves as a valuable benchmark for carbon-based materials such as graphene. We have studied copper on graphite, using STM in UHV, to determine the characteristic features of nucleation and growth of metal islands in this system. We have varied the parameters of deposition temperature, Cu coverage, and Cu flux. In the pre-coalescence regime of coverage, we find that Cu decorates step edges and also forms three-dimensional islands on the terraces. The areal density of the islands is 10-4 to 10-3 nm-2, after growth at temperatures of 180 to 300 K, over a range of Cu flux and Cu coverage. This relatively-invariant density indicates that nucleation is heterogeneous. After annealing above room temperature (but well below the onset of desorption at about 900 K), both the density of Cu islands and the total volume of Cu are much lower. DFT is used to understand the processes and energetics in this system.