The decay kinetics of 2D TiN adatom and vacancy islands on highly anisotropic TiN(111) surfaces were measured using in situ high-temperature STM. There was an abrupt decrease in decay rates for adatom islands with areas A less than a critical value Ac≃1600 Å2, irrespective of Ta. However, no decay rate transition was observed for vacancy islands. The coarsening/decay kinetics of both adatom and vacancy islands on TiN(111) were found to be consistent with a detachment-limited mechanism. From time- and temperature-dependent island area measurements, activation energies were obtained for TiN(111) adatom island decay of 3.3±0.4 eV (A<Ac) and 2.3±0.6 eV (A>Ac). Overall, the results provide the first evidence of a strong island size-dependence, and therefore a large anisotropy in attachment/detachment activation barriers.
ASJC Scopus subject areas
- Physics and Astronomy(all)