Nonlinear properties of fractal growth of thin films at low temperature

Fractal growth of thin films at low temperature (75-200 K) is simulated by kinetic Monte Carlo method, using realistic growth model-Ag on Pt(111) surface and physical parameters. It is shown that the fractal growth of thin films is nonlinear, i. e., the island size S(t) grows with time t as tk ) where the growth exponent k is slightly less than 1 because of the growth competition of islands and the competition between nucleation and growth of islands. The further results indicate that the branch width of islands b increases with increasing island size S as b -Sa, where a is approximately equal to 1/3 because of the geometrical structure of the triangular substrate.