MOCVD-Derived Highly Transparent, Conductive Zinc- and Tin-Doped Indium Oxide Thin Films: Precursor Synthesis, Metastable Phase Film Growth and Characterization, and Application as Anodes in Polymer Light-Emitting Diodes
datasetposted on 20.04.2005, 00:00 by Jun Ni, He Yan, Anchuang Wang, Yu Yang, Charlotte L. Stern, Andrew W. Metz, Shu Jin, Lian Wang, Tobin J. Marks, John R. Ireland, Carl R. Kannewurf
Four diamine adducts of bis(hexafluoroacetylacetonato)zinc [Zn(hfa)2·(diamine)] can be synthesized in a single-step reaction. Single crystal X-ray diffraction studies reveal monomeric, six-coordinate structures. The thermal stabilities and vapor phase transport properties of these new complexes are considerably greater than those of conventional solid zinc metal−organic chemical vapor deposition (MOCVD) precursors. One of the complexes in the series, bis(1,1,1,5,5,5-hexafluoro-2,4-pentadionato)(N,N‘-diethylethylenediamine)zinc, is particularly effective in the growth of thin films of the transparent conducting oxide Zn−In−Sn−O (ZITO) because of its superior volatility and low melting point of 64 °C. ZITO thin films with In contents ranging from 40 to 70 cation % (a metastable phase) were grown by low-pressure MOCVD. These films exhibit conductivity as high as 2900 S/cm and optical transparency comparable to or greater than that of commercial Sn-doped indium oxide (ITO) films. ZITO films with the nominal composition of ZnIn2.0Sn1.5Oz were used in fabrication of polymer light-emitting diodes. These devices exhibit light outputs and current efficiencies almost 70% greater than those of ITO-based control devices.