AVS 59th Annual International Symposium and Exhibition
    Thin Film Thursday Sessions
       Session TF+EM+SS-ThA

Paper TF+EM+SS-ThA10
Self Limiting Behavior in the Directed Self-Assembly of Mounds on Patterned GaAs(001)

Thursday, November 1, 2012, 5:00 pm, Room 10

Session: Applications of Self-Assembled Monolayers and Layer-by-Layer Assemblies
Presenter: C.-F. Lin, University of Maryland
Authors: C.-F. Lin, University of Maryland
C.J.K. Richardson, Laboratory for Physical Science
H.-C. Kan, University of Maryland
N.C. Bartelt, Sandia National Laboratories
R.J. Phaneuf, University of Maryland
Correspondent: Click to Email
We present results demonstrating directed self assembly of nm scale mounds during molecular beam epitaxial growth on patterned GaAs(001) surfaces. In the initial stages of growth, a lithographically-defined pattern directs the spontaneous formation of multilayer islands at the centers of bridges between near-neighbor nanopits along [110] crystal orientation, seemingly due to the presence of an Ehrlich-Schwoebel barrier. As growth continues, the heights of mounds at these 2-fold bridge sites “self-limit”. Beyond this point mounds at other, 4-fold bridge sites dominate the topography, but these self-limit as well. This behavior suggests the existence of a minimum, ‘critical terrace width’ for nucleation of islands during growth, and provides a physical mechanism for understanding the transient nature of the observed instability during growth on these patterned surfaces