| The growing importance of cadmium containing thin films and the desire for their efficient deposition has necessitated the development of high performance MOCVD precursors. To this end, a series of low-melting, and thermally-stable cadmium MOCVD precursors has been synthesized, characterized, and implemented in the growth of highly conductive and transparent CdO-based thin films. One member of the series, bis(1,1,1,5,5,5-hexafluoro-2,4-pentanedionato)(N,N-diethyl-N ', N'-dimethyl-ethylenediamine)cadmium(II), Cd(hfa)2(N,N-DE-N' ,N'-DMEDA), represents a particularly significant improvement over previously available Cd precursors owing to its low melting point, and robust thermal stability. This precursor will allow careful control of composition and growth rates in complex cadmium-containing oxide systems owing to the elimination of sintering effects detrimental to reproducible growth with solid precursors.; Materials with high electrical conductivity and optical transparency are needed for future flat panel display, solar energy, and other opto-electronic technologies. High quality Cd1-xInxO films with been deposited utilizing our new class of MOCVD precursors. The x = 0.05 film, with conductivity of 17,000 S/cm, carrier mobility of 70 cm2/V·s, and wide visible region optical transparency window considerably exceed the corresponding parameters for commercial indium-tin oxide (ITO).; A detailed understanding of the fundamental aspects of charge transport in degenerate semiconductors is of great interest. In order to elucidate the importance of individual scattering mechanisms in TCO materials, high-quality CdO films were grown by MOCVD in parallel on glass and single-crystal MgO (100) between 300°C and 412°C. Enhanced mobilities observed for highly biaxially textured films grown on MgO (100) vs. glass are attributed, on the basis of DC charge transport measurements and microstructure analysis, to a reduction in neutral impurity scattering and/or to a more densely packed grain microstructure. Although single grained films grown on MgO (100) exhibit greater mobilities than analogues with discrete ∼100 nm grains and similar texture, this effect is attributed, on the basis of charge transport and Hall effect measurements as well as optical reflectivity analysis to small differences in carrier concentration, rather than to a reduction in grain boundary scattering. Conductivities and mobilities as high as 11,000 S/cm and 307 cm2/V·s, respectively, are obtained for epitaxial single-grained CdO films grown in situ on MgO (100). |
