화학공학소재연구정보센터
AIChE Journal, Vol.50, No.8, 1881-1888, 2004
Susceptibility of SiO2, ZrO2, and HfO2 dielectrics to moisture contamination
Moisture contamination of HfO2 and ZrO2 ultrathin dielectric films, deposited by atomic layer chemical vapor deposition (ALCVD(TM)), is investigated and compared to that of native SiO2. Results show that HfO2 and ZrO2 surfaces adsorb higher amounts of moisture and bind moisture more strongly than SiO2 surfaces. A multilayer model is developed to represent the dynamics of moisture interaction with these three oxides. Using this model, the fundamental kinetic parameters are determined. The adsorption rate constants are of the same order of magnitude for all three surfaces. However, the desorption rate constants for ZrO2 and HfO2 are almost three orders of magnitude lower than that for SiO2. Activation energies for desorption of water molecules from the first two layers are 33, 27, and 19 kJ/mol, for ZrO2, HfO2, and SiO2, respectively. Results obtained in this study suggest that the HfO2 and ZrO2, as the new dielectric materials, are more prone to moisture contamination than SiO2. (C) 2004 American Institute of Chemical Engineers.