Crystallization of lithium cobalt oxide thin films by radio-frequency plasma irradiation

The crystallinity of lithium cobalt oxide thin films deposited by the radio -frequency (rf) reactive magnetron sputtering method has been improved by t he rf plasma irradiation method. Compared with conventional thermal anneali ng, reaction to form crystalline lithium cobalt oxide via rf plasma irradia tion is fast and does not need any additional external heat supply. It is f ound that the nucleation and the growth reactions are determined during the film deposition and the rf irradiation, respectively. The film composition does not change significantly, and severe mechanical damages such as respu ttering or etching phenomena do not appear after the irradiation. A model s howing the process of the crystallization by rf plasma irradiation is sugge sted on the basis of phenomenological analyses using secondary electron mic roscopy, high-resolution transmission electron microscopy, etc. (C) 2001 Am erican Institute of Physics.