Structural Analysis of Submicrometer LiCoO[sub 2] Films

Abstract

Submicrometer LiCoO 2 films were prepared with pulsed laser deposition PLD and rf sputtering using stoichiometric targets. The influences of both substrate material and annealing procedure on the polycrystalline microstructure of the LiCoO 2 films were investigated. XRD analysis revealed strong preferential orientation: annealed films deposited with PLD had their 00l planes parallel to the surface, while rf sputtered films had their 110 planes in this orientation. The rf-film also developed the 003 reflection typical of PLD-films, but only after prolonged annealing at 600C. The degree of preferential orientation is influenced significantly by the annealing procedure and only little by the substrate material and the thickness of the deposited film. Pulsed laser deposition on an rf-sputtered seed layer revealed the PLD-film reflections. Extinction of the otherwise dominating 003 reflection indicated a random cationic distribution in LiCoO 2 with an NaCl-type structure.