abstract
PbTiO3 thin films were deposited on Si and Ru substrates by atomic layer deposition at a substrate temperature of 200 degrees C using H2O and O-3 as oxygen sources and lead(II) bis(3-N,N-dimethylamino-2-methyl-2-propoxide) and titanium(IV) isopropoxide as the Pb and Ti precursors, respectively. When H2O was used as the oxygen source for both Pb and Ti precursors, film growth was most effective under the conditions where a stoichiometric PTO film was achieved (Pb/Ti concentration ratio similar to 1). On the other hand, the PTO growth per cycle increased with increasing the PbOx/TiO2 subcycle ratio when O-3 was used as the oxygen source for the Ti precursor, even when Pb-rich PTO films were deposited. These unexpected results were explained by the different reactions occurring according to the oxygen source used, in particular, by a reaction mechanism involving the direct condensation between surface formate species and alkoxy species in the case of ozone.
keywords
QUADRUPOLE MASS-SPECTROMETRY; ELECTRICAL-PROPERTIES; OXIDE; H2O; RU; ROUTES; TRIMETHYLALUMINUM; DIELECTRICS; PRECURSORS; TITANIUM
subject category
Chemistry; Science & Technology - Other Topics; Materials Science
authors
Lee, HJ; Park, MH; Min, YS; Clavel, G; Pinna, N; Hwang, CS
our authors
Nicola Pinna
ResearcherGroups
acknowledgements
The study was supported by the Converging Research Center Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0081961), the National Program for 0.1 Terabit NVM Devices of the Korean Government, the World Class University program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R31-2008-000-10075-0) and (R31-10013), and FCT Project No. PTDC/CTM/65667/2006.