Hafnium oxide (HfO 2 ) and zirconium oxide (ZrO 2 ) are two high-materials having the potential to replace silicon oxide (SiO 2 ) as the gate dielectric. Atmospheric molecular contamination can affect the quality of the new gate dielectric film in a manner similar to SiO 2 . Characterization of contaminant adsorption behavior of these high-films should assist in deciding their potential for successful integration in silicon metal oxide semiconductor technology. The interaction of moisture and organics ͑in particular, isopropanol, IPA͒ as common interfacial contaminants with a 5 nm HfO 2 film deposited by atomic layer chemical vapor deposition ͑ALCVD͒, which is a trademark of ASM International͒ is investigated using atmospheric pressure ionization mass spectrometry ͑APIMS͒; the kinetics and mechanism are compared to that of ZrO 2 and SiO 2 . HfO 2 and ZrO 2 have similar moisture adsorption loading, but are significantly higher than that of SiO 2 . However, almost all the adsorbed moisture can be removed from SiO 2 and HfO 2 after a 300°C bake under nitrogen purge, whereas ZrO 2 surfaces retain 20-30% of the adsorbed moisture. Experiments with IPA show that the adsorption loading on the three surfaces has the following order: ZrO 2 Ͼ HfO 2 Ͼ SiO 2 . A multilayer model for adsorption of water and IPA is developed to understand the mechanism of interactions of contaminants with the three surfaces. Results from the application of this multilayer model to the experimental data indicate that ZrO 2 forms the strongest surfacehydroxyl ͑X-OH͒ bond.

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The effect of various processing conditions on the extent of adsorption of organics and incorporation of carbon in normalSi/SiO2 during thermal oxidation is investigated. The key parameters studied are preoxidation cleaning, temperature-ramp rate and ambient, gas-phase impurity concentration, and the presence of moisture. A novel method based on the catalytic oxidation of organics is developed to monitor and characterize the outgassing of organics. Results show that SC1-last surfaces adsorb more polar organics than do HF-last surfaces; this results in a higher amount of carbon incorporation. HF-last surfaces, however, retain a larger fraction of the adsorbed organics. Addition of oxygen to the temperature-ramp ambient reduces the extent of carbon incorporation. The kinetics and mechanisms of carbon incorporation in normalSi/SiO2 substrates are investigated. A reaction model based on the competitive processes of desorption, readsorption, decomposition, oxidation, and chemisorption of the adsorbed organics is developed. This model provides a better understanding of one of the key aspects of defect formation in silicon-based dielectric thin films. © 2002 The Electrochemical Society. All rights reserved.