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Indium–zinc oxide films (ZnxInyOx+1.5y), with x/y=0.08–12.0, are grown by low-pressure metal-organic chemical vapor deposition using the volatile metal–organic precursors In(TMHD)3 and Zn(TMHD)2 (TMHD=2,2,6,6–tetramethyl–3,5–heptanedionato). Films are smooth (rms roughness=40–50 Å) with complex microstructures which vary with composition. The highest conductivity is found at x/y=0.33, with σ=1000 S/cm (n-type; carrier density=3.7×1020 cm3; mobility=18.6 cm2/V s; dσ/dT<0). The optical transmission window of such films is broader than Sn-doped In2O3, and the absolute transparency rivals or exceeds that of the most transparent conductive oxides. X-ray diffraction, high resolution transmission electron microscopy, microdiffraction, and high resolution energy dispersive X-ray analysis show that such films are composed of a layered ZnkIn2O3+k phase precipitated in a cubic In2O3:Zn matrix.

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A new class of volatile, low-melting, fluorine-free lanthanide metal-organic chemical vapor deposition (MOCVD) precursors has been developed. The neutral, monomeric Ce, Nd, Gd, and Er complexes are coordinatively saturated by a versatile, multidentate ether-functionalized beta-ketoiminato ligand series, the melting point and volatility characteristics of which can be tuned by altering the alkyl substituents on the keto, imino, and ether sites of the ligand. Direct comparison with conventional lanthanide beta-diketonate complexes reveals that the present precursor class is a superior choice for lanthanide oxide MOCVD. Epitaxial CeO(2) buffer layer films can be grown on (001) YSZ substrates by MOCVD at significantly lower temperatures (450-650 degrees C) than previously possible by using one of the newly developed cerium beta-ketoiminate precursors. Films deposited at 540 degrees C have good out-of-plane (Deltaomega = 0.85 degrees ) and in-plane (Deltaphi = 1.65 degrees ) alignment and smooth surfaces (rms roughness approximately 4.3 A). The film growth rate decreases and the films tend to be smoother as the deposition temperature is increased. High-quality yttrium barium copper oxide (YBCO) films grown on these CeO(2) buffer layers by pulsed organometallic molecular beam epitaxy exhibit very good electrical transport properties (T(c) = 86.5 K, J(c) = 1.08 x 10(6) A/cm(2) at 77.4 K).

The flatbandhhreshold voltages (VJV,) in poly-Si gated pFETs with Hf-based gate dielectrics are shown to be set during poly-Si deposition and are found to remain virtually unchanged during gate implantation and activation, independent of the p-type dopant. The reaction of Si with HfO2 at poly-Si deposition temperatures is identified as the root cause for the poor VJV, control. No improvement in V, control is obtained by engineering physically closed Si3N4 barrier layers on Hf02. It is furthermore shown for the first time that even when the gate is fully silicided (FUSI) large VnJV, shifts are observed with HfO,. Reduced pFET shifts are observed when Hf-silicates with low Hf content are used and further improvements are observed by using AI203 cap layers on silicates.

Abshact-YB~Cu30x (YBCO) films have been deposited on buffered metal substrates by metal organic chemical-vapor deposition (MOCVD). Nickel alloy substrates with biaxirdlytextured yttria-stabilized zirconia (YSZ) buffer layers deposited by ion-beam-assisted deposition (IBAD) were used. A liquidstatic precursor delivery system was designed, constructed, and used in the MOCVD facility at Intermagnetics for the reported work. At 77 & under self-field conditions, we achieved a critical current (Q of 97.5 A in YBCO film grown by MOCVD on an IBAD substrate. This ICcorresponds to a critical current density of 1.3 MA/cm2 and 130 A/cm width of tape.

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