Recent Developments on MOCVD of Ferroelectric Thin Films

    loading  Checking for direct PDF access through Ovid

Abstract

Ferroelectric Pb(Zr, Ti)O3 thin films were fabricated by liquid delivery MOCVD using Pb(DPM)2, Ti(OiPr)2(DPM)2 and Zr(DIBM)4. The deposition rate of 12.3 nm/min was attained on 6-inch Pt/Ti/SiO2/Si wafers at 550°C. The average and the deviation of twofold remanent polarization were 45.5 μC/cm2 and ± 6.4%, respectively, over the 6-inch wafer. Step coverage was improved from 44% to 90% by decreasing deposition temperature from 550 to 400°C although the deposition rate decreased by 60%. TiO2 nanoparticles diffused to the surface of platinum bottom electrodes were effective as a seed to obtain 111 preferential oriented PZT thin films at the deposition temperature of 550°C. Iridium oxide bottom electrodes were reduced to metal ones by CO and/or H2 gases generated by decomposition of precursors. Oxide materials seem to be not the best as bottom electrodes in liquid delivery MOCVD. A cocktail source consisted of Pb(METHD)2, Ti(MPD)(METHD)2 and Zr(METHD)4 was also examined. PbPtx alloy phase existed in PZT films deposited at 500°C was disappeared by post-annealing at 600°C and the annealed film showed hysteresis properties with the 2Pr of 56 μC/cm2 and the 2Ec of 181 kV/cm.

Related Topics

    loading  Loading Related Articles