In this work, we evaluated novel Sr and Ti precursors for atomic layer deposition application. Traditional Sr precursor Sr(thd)2 is a solid with very low vapor pressure, high melting point, and requires high temperature oxidation for efficient carbon removal.. In comparison, bulky cyclopentadienyl based Sr compounds display high vapor pressures, low melting points, reactivity with water and high ALD growth rates. We also evaluated the effect of various stabilizing adducts on the properties of Sr cyclopentadienyl precursors and on the SrO ALD process. Sr precursors studied include AbsoluteSr Sr(iPr3Cp)2, HyperSr.THF Sr(iPr3Cp)2.2THF, HyperSr.DME Sr(iPr3Cp)2.DME, StarSr.THF Sr(Me5Cp)2.THF and StarSr.DME Sr(iPr3Cp)2.DME. Novel Ti precursors like PrimeTi (Ti(MeCp)(OMe)3), StarTi (Ti(Me5Cp)(OMe)3), TyALD (TiCp(NMe2)3) and StarTyALD (TiMe5Cp(NMe2)3) developed using heteroleptic chemistry are evaluated for TiO2 ALD. Finally, compatibility of the novel HyperSr.THF along with Ti precursors such as PrimeTi and StarTi in terms of composition tunability and material properties for STO ALD are studied.

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A nonpyrophoric, oxygen-free, halogen-free tris͑diethylamino͒ aluminum ͑TDEAA͒ precursor was used for atomic layer deposition ͑ALD͒ of aluminum oxide on Si͑100͒. ALD of aluminum oxide using TDEAA and water was found to be self-limiting with respect to both reactants. The temperature window for ALD in the hotwall reactor used was found to be between 200 and 400°C. The ALD rate was 1.4 Å/cycle at optimum conditions. Fourier transform infrared ͑FTIR͒ analyses indicated negligible interfacial SiO 2 growth during deposition. Both FTIR spectra and transmission electron micrographs showed the ALD aluminum oxide to be amorphous. Also, FTIR and X-ray photoelectron spectral ͑XPS͒ analyses showed negligible carbon and nitrogen ͑Ͻ1% atomic͒ contamination in the film. Z-contrast images and electron energy loss spectra showed uniform aluminum oxide film with an abrupt interface with Si. XPS analysis revealed aluminum oxide film to be stoichiometric with no detectable Al-Al cluster formation. Also, XP spectra showed no silicate formation at the interface of as-deposited alumina films.