Substrate effect on microstructure of LiCoO2 thin film cathodes

LiCoO2 thin films were prepared by pulsed laser deposition technique on different substrates with respect to deposition parameters. The surface morphological features of the deposited films were studied by scanning electron microscopy (SEM) with respect to different substrates. The SEM data demonstrated that the LiCoO2 films deposited on Pyrex glass substrate have rough surface with several dispatches of grains, where as the films deposited on silicon substrate showed very fine and uniform particles without dispatches of grains. The films deposited on flexible substrate showed non-uniform grains and dispatches of grains due to discontinuity in the film. These results showed that the selection of an appropriate substrate is important for fabricating the thin film electrode with the high rate capacity, especially considering the application of microbatteries.