Chad Yuen

Publications (2)11.57 Total impact

• Source

  Available from: Patricia A Thiel

  Article: Self-assembly of metal nanostructures on binary alloy surfaces.

  T Duguet, Yong Han, Chad Yuen, Dapeng Jing, Barış Unal, J W Evans, P A Thiel
  [show abstract] [hide abstract]
  ABSTRACT: Deposition of metals on binary alloy surfaces offers new possibilities for guiding the formation of functional metal nanostructures. This idea is explored with scanning tunneling microscopy studies and atomistic-level analysis and modeling of nonequilibrium island formation. For Au/NiAl(110), complex monolayer structures are found and compared with the simple fcc(110) bilayer structure recently observed for Ag/NiAl(110). We also consider a more complex codeposition system, (Ni + Al)/NiAl(110), which offers the opportunity for fundamental studies of self-growth of alloys including deviations for equilibrium ordering. A general multisite lattice-gas model framework enables analysis of structure selection and morphological evolution in these systems.
  Proceedings of the National Academy of Sciences 01/2011; 108(3):989-94. · 9.68 Impact Factor
• Article: Stranski–Krastanov-like growth of an Ag film on a metallic glass

  Dapeng Jing, Barış Ünal, Feili Qin, Chad Yuen, J.W. Evans, C.J. Jenks, D.J. Sordelet, P.A. Thiel
  [show abstract] [hide abstract]
  ABSTRACT: We have studied the morphology of a bulk-crystalline metal, Ag, deposited on a clean surface of a metallic glass, Zr–Ni–Cu–Al. At 190–300 K, the films exhibit Stranski–Krastanov-like growth, wherein three-dimensional clusters form atop an Ag wetting layer that is 4–5 monolayers thick. Above this coverage, cluster growth competes with growth of the flatter regions. The cluster density increases with decreasing temperature, indicating that the conditions of island nucleation are far-from-equilibrium. Within a simple model where clusters nucleate whenever two mobile Ag adatoms meet, the temperature-dependence of cluster density yields an (reasonable) upper limit for the value of the Ag diffusion barrier on top of the Ag wetting layer of 0.32 eV. Overall, this prototypical study suggests that it is possible to grow films of a bulk-crystalline metal that adopts the amorphous character of a glassy metal substrate, if film thickness is sufficiently low.
  Thin Solid Films 517(24):6486-6492. · 1.89 Impact Factor