Accession Number : ADP006685

Title :   Low Temperature Processing of Ferroelectric Thin Films and Amorphous Ferroelectricity,

Corporate Author : CALIFORNIA UNIV LOS ANGELES DEPT OF MATERIALS SCIENCE AND ENGINEERING

Personal Author(s) : Xu, Ren ; Xu, Yuhuan ; Mackenzie, John D.

Report Date : 05 APR 1991

Pagination or Media Count : 10

Abstract : LiNbO3 thin films on various substrates were fabricated from sol-gel process. Epitaxial growth of LiNbO3 On sapphire(012), single crystal LiTaO3(l 10) and single crystal LiNbO3(001) were found. Water addition in the solution prior to film deposition was found to be unnecessary. Crystallization temperature was between 350 deg C and 450 deg C in air. Amorphous gel films stabilized at temperatures ranging from 25 deg C to 250 deg C at different Li/Nb ratios were also found to show P-E hysteresis loops. Pr and Ec values were in the same order of magnitude as those of single crystal LiNbO3. Pyroelectric coefficients were measured. Auger and IR spectra were used to study the gel film composition and structure. X-ray and electron diffractions were used to confirm the amorphousness of these gel films. Amorphous ferroelectricity was used to account for these observations.

Descriptors :   *EPITAXIAL GROWTH, *THIN FILMS, *LITHIUM NIOBATES, COEFFICIENTS, CRYSTALLIZATION, CRYSTALS, DEPOSITION, FERROELECTRICITY, GELS, HYSTERESIS, LOOPS, RATIOS, SINGLE CRYSTALS, SPECTRA, STRUCTURES, SUBSTRATES, TEMPERATURE, AUGER ELECTRON SPECTROSCOPY.

Subject Categories : Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE