Scaling laws in annealed LiCoOx films

The surface morphology evolution due to the annealing process of LiCoOx thi n films deposited by rf sputtering is studied by means of an atomic force m icroscope. Linear relationships were observed in log-log plots of interface width versus window length, as predicted by scaling laws. For as-grown fil ms, only one growth exponent ais evidenced. For annealed films two differen t slopes alpha(1) and alpha(2) were observed, indicating distinct growth dy namics in the system. The roughness exponent for the as-grown film and the internal morphology of the crystalline grains for the annealed films can be described by a diffusional process. The macrostructure shows characteristi cs of a Kardar-Parisi-Zhang system [M. Kardar, G. Parisi, Y. C. Zhang, Phys . Rev. Lett. 56, 889 (1986); J. Krim and G. Palasantzas, Int. J. Mod. Phys. B 9, 599 (1995)]. An activation energy E-d = (0.11 +/-0.01) eV is determin ed for the diffusion process. (C) 1999 American Institute of Physics. [S000 3-6951(99)02212-3].