PREPARATION OF (100)-ORIENTED LaNiO3 OXIDE ELECTRODES FOR SrBi2Ta2O9-BASED FERROELECTRIC CAPACITORS

LaNiO3 thin films were prepared on SiO2/Si and Pt/Ti/SiO2/Si substrates using a modified sol-gel technique. To decrease the annealing temperature, LaNiO3 thin films were annealed layer-by-layer in a RTA furnace. The effects of preheating temperature and annealing temperature on the crystallographic orientation and resistivity of LaNiO3 thin films were studied resp. (100)-oriented LaNiO3 thin films can be formed on SiO2/Si and Pt/Ti/SiO2/Si substrates at an annealing temperature of 600 C. The typical room-temperature resistivity of the (100)-oriented LaNiO3 thin films deposited on SiO2/Si substrates is about 4.7x 10-4 OHM cm. To verify the function of LaNiO3 thin films as the bottom electrodes of ferroelectric capacitors, SrBi2Ta2O9 thin films were fabricated on LaNiO3-coated Pt/Ti/SiO2/Si substrates by the metal organic decomposition technique. No evident fatigue was observed for an SrBi2Ta2O9 thin film annealed at 600 C, although its remanent polarization is not as large as that for the SrBi2Ta2O9 thin films deposited directly on Pt/Ti/SiO2/Si substrates. 9 refs.