Systematic study and performance optimization of transparent conducting indium-zinc oxides thin films

To optimize the physical properties of In2O3-ZnO pulsed laser deposited thi n films, we embarked on a systematic study of their microstructural charact erization and transport properties. We found that the electrical properties of the films are greatly governed by their microstructure, which evolves f rom granular to frber and to columnar textures, as we go from cubic In2O3 t o hexagonal ZnO via ZnkIn2Ok+3 layered structure in the binary In2O3-ZnO ph ase diagram. Maximum conductivity is reached for a Zn/(Zn + In)= 0.5 (at.) composition having a layered ZnkIn2Ok+3-type structure with essentially k = 2, which was synthesized for the first time. Electrochemical measurements show that this film can be used as a transparent electrode in electrochromi c devices operating either in an aqueous or organic medium. (C) 2001 Elsevi er Science Ltd. All rights reserved.