AVS 46th International Symposium
    Surface Science Division Thursday Sessions
       Session SS1+EM+NS-ThA

Paper SS1+EM+NS-ThA2
Non Capillarity Driven Grain Growth in a Strained Cu Ultrathin Film

Thursday, October 28, 1999, 2:20 pm, Room 606

Session: Metal/Metal Growth
Presenter: A.K. Schmid, Sandia National Laboratories
Authors: A.K. Schmid, Sandia National Laboratories
T. Giessel, Sandia National Laboratories
N.C. Bartelt, Sandia National Laboratories
J. de la Figuera, Sandia National Laboratories
R.Q. Hwang, Sandia National Laboratories
Correspondent: Click to Email
Properties of metal films are crucially influenced by details of their grain structure. To determine basic mechanisms of grain evolution we have investigated a prototypical granular thin film using LEEM and STM. In two monolayer thick films of Cu on Ru(0001) a uniaxial relaxation relieves the misfit strain (5.5%) with the substrate, leading to a two-dimensional grain structure consisting of three orientationally different domain types. We observed in-situ grain growth using LEEM in dark field imaging mode and took STM snap shots at several stages of the grain evolution. While on large scale of both time and area the total length of grain boundary decreases in order to reduce the free energy of the system an increase of boundary length has been observed locally and on smaller time scale. The observed behavior can not be described within the framework of a Q-state Potts model which has been widely used for the description of grain growth. We show that the long-ranged lateral interactions between the surface atoms in the strained Cu film which are not considered in Potts model are responsible for the observed behavior.