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Thin films of composition Ti x Si 1±x O 2 were grown by low-pressure (LP) CVD on silicon (100) , as the sources of SiO 2 and TiO 2 , respectively. The substrate temperature was varied between 300 C and 535 C, and the individual precursor delivery rates ranged from 5 sccm to 100 sccm. Under these conditions, growth rates ranging from 0.6 nm min ±1 to 90.0 nm min ±1 were observed. As-deposited films were amorphous to X-rays, and cross-sectional transmission electron microscopy (TEM) images showed no compositional inhomogeneity. Rutherford backscattering (RBS) spectrometry revealed that the relative concentration of TiO 2 and SiO 2 was dependent upon the choice of TiO 2 precursor. Possible multi-precursor deposition scenarios are presented and discussed in relation to the observed variation of film stoichiometry. For the TTIP±TEOS pair, the systematic variation of Ti content with deposition conditions could be accounted for by a growth scenario that limits SiO 2 growth to TiO 2 sites within the composite film. For the case of TN±TEOS the Ti content remained close to 50 % for all conditions studied. A specific chemical reaction between TN and TEOS prior to film deposition accounts for the observed composition.

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Anhydrous zirconium(IV) nitrate was used as a volatile, carbon-free precursor for the low pressure chemical vapor deposition of thin ZrO 2 films on silicon (100) substrates. Depositions were performed at substrate temperatures between 300 and 500ЊC at total reactor pressures between 0.25 and 1.1 Torr. During deposition the N 2 carrier gas (flow rates ϭ 20 or 100 sccm) was diverted through the precursor vessel which was maintained between 80 and 95ЊC. Under these conditions typical growth rates reached 10.0 nm/min. The polycrystalline films were predominantly monoclinic ZrO 2 with compositions very near the ideal value. Crosssectional transmission electron microscopy and medium energy ion scattering established that an interfacial layer of SiO 2 separates the silicon substrate from the ZrO 2 . Electrical measurements made on capacitors constructed of 58 nm thick films of ZrO 2 with a platinum top electrode suggest that charge trapping occurs in the Si/ZrO 2 interfacial region.

A low-pressure chemical vapor deposition (CVD) reactor was modified to produce a continuous compositional spread of titanium, tin, and hafnium dioxides on a single Si(100) wafer. The corresponding anhydrous metal nitrates, Ti(NO 3 ) 4 , Sn(NO 3 ) 4 , and Hf(NO 3 ) 4 , were used as single-source precursors to the component oxides. The compositions were mapped using X-ray photoelectron spectroscopy and Rutherford backscattering spectrometry. On a single wafer an array of 100 µm × 100 µm capacitors was used to map the effective dielectric constant (κ eff ) of the films. For compositional spreads grown at 400 and 450 °C κ eff reached a maximum value in regions with the highest concentrations of TiO 2 . The formation of the orthorhombic R-PbO 2 phase for a composition near Hf 0.75 Sn 0.25 O 2 was also observed in the 450 °C compositional spread.