Title :
Characterization and electrical properties of chemical vapor deposited ferroelectric lead titanate films on titanium
Author :
Yoon, Soon Gil ; Kim, Ho Gi
Author_Institution :
Dept. of Mater. Sci. & Eng., Korea Adv. Inst. of Sci. & Technol., Seoul, South Korea
Abstract :
Lead titanate thin films were deposited on titanium substrates by a chemical vapor deposition (CVD) process involving the application of vapor mixtures of Pb, ethyl titanate (Ti(C/sub 2/H/sub 5/O)/sub 4/), and oxygen. Auger electron spectroscopy (AES) analyses were performed to determine the chemical composition of lead titanate films. AES analysis revealed that TiO/sub 2/ and TiO interlayers formed between the PbTiO/sub 3/ and titanium substrate. AES also showed that stoichiometry was obtained in the lead titanate film deposited at 750 degrees C, Ti(C/sub 2/H/sub 2/O)/sub 4/ with 0.152, an O/sub 2/ partial pressure of 0.06 atm, and a gas flow rate of 800 sccm. The lead titanate with a stoichiometric composition has a DC conductivity of 3.2*10/sup -12/ Omega /sup -1/-cm/sup -1/ at room temperature. The nonsaturating loops observed in the present investigation may be caused by TiO/sub 2/ and TiO layers between the conductive substrate and the PbTiO/sub 3/ ferroelectric film. The ferroelectric properties of the stoichiometric PbTiO/sub 3/ film included a remanent polarization of 14.1 mu C/cm/sup 3/ and a coercive field of 20.16 kV/cm.<>
Keywords :
Auger effect; chemical vapour deposition; dielectric polarisation; electronic conduction in insulating thin films; ferroelectric materials; ferroelectric thin films; lead compounds; stoichiometry; 0.06 atm; 300 K; 750 degC; AES; Auger electron spectroscopy; CVD; DC conductivity; O/sub 2/ partial pressure; PbTiO/sub 3/ ferroelectric film; Ti substrate; TiO interlayers; TiO/sub 2/ interlayers; chemical composition; chemical vapor deposition; coercive field; conductive substrate; electrical properties; gas flow rate; nonsaturating loops; remanent polarization; room temperature; stoichiometry; vapor mixtures; Chemical analysis; Chemical vapor deposition; Electrons; Ferroelectric films; Lead; Performance analysis; Spectroscopy; Sputtering; Substrates; Titanium compounds;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on