Preparation of PbTiO 3 Thin Film by Mist Source Plasma Enhanced Chemical Vapor Deposition (CVD) Using Heptane Solvent

• Published in: Japanese Journal of Applied Physics 1999-09, Vol.38 (9S), p.5326
• Main Authors: Wakiya, Naoki, Nagata, Shingo, Higuchi, Masashi, Shinozaki, Kazuo, Mizutani, Nobuyasu
• Format: Article
• Language: English
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.38.5326

Heptane has been proposed as a new solvent for liquid source chemical vapor deposition (LSCVD) and liquid source mist chemical vapor deposition (LSMCVD) instead of tetrahydrofuran (THF). The range of the explosive limit of heptane is much narrower than that of THF, and heptane does not have self-explosive characteristics unlike THF. The boiling point of heptane is higher than that of THF, therefore, selective vaporization of the solvent can be avoided. The preparation of PbTiO 3 thin films was attempted using a liquid source in which Pb(DPM) 2 and Ti(O-i-Pr) 4 were dissolved in heptane. The substituent exchange reaction was not perceived in heptane. Moreover, fine mists of the solution could be generated using an ultrasonic nebulizer. These facts indicate that heptane is an excellent solvent. The solution was applied to the plasma-enhanced LSMCVD apparatus and PbTiO 3 thin films having stoichiometric composition and smooth and flat microstructures were prepared on Pt/Ti/SiO 2 /Si substrates. The dielectric and ferroelectric properties of PbTiO 3 thin films agree well with those reported in literature.