Ferroelectric Pb(Zr,Ti)O3 (PZT) thin films were fabricated by liquid delivery MOCVD using conventional multi-sources. The deposition rate of 20 nm/min was attained at the reactor pressure of 5 Torr and the substrate temperature of 550°C by using Zr(DIBM)4 as a Zr-source instead of Zr(DPM)4. The step coverage increased from 50 to 100% by decreasing the substrate temperature from 600 to 400°C although the deposition rate decreased to the half. The uniform PZT thin films were successfully formed on 6-inch wafers. The variation in thickness was less than 5% all over the wafers. However, the remanent polarization at the center was half of that at the border. A cocktail source prepared by mixing Pb(METHD)2, Zr(METHD)4 and Ti(MPD)(METHD)2 with ECH was also examined. The cocktail source was stable for 3 months. PZT thin films deposited using the cocktail source exhibited ferroelectric properties. However, strongly oriented PbPtx alloy and oriented PbO were also formed. The improvement in crystallinity, electrical properties and surface morphology remains for future study.
No takes yet. Share an insight, caveat, or question.
Shiosaki et al. (2003) studied this question.