Epitaxial ferroelectric capacitors obtained by MOCVD

Thin films of metallic oxides La0.5Sr0.5CoO3, La NiO3, [La0.5Sr0.5CoO3]l-x[LaNiO3]x and ferroelectrics PbZrxTi1-xO3 were deposited by single source MOCVD using M(thd)n compounds. After the deposition conditions of individual layers were optimized, the epitaxial capacitors LaNiO3/PbTiO3/LaNiO3, [La0.5Sr0.5CoO3]0.5[LaNiO3]0.5/PbTiO3/[La0.5Sr0.5CoO3]0.5[LaNiO3]0.5 and La0.5Sr0.5CoO3/PbTiO3/La0.5Sr0.5CoO3 were prepared on MgO single crystal substrates. The materials obtained were characterized by XRD, SEM, EDX, AFM, HREM and Raman spectrometry. For ferroelectric measurements on each wafer the series of capacitors with common bottom electrode and separate top electrode plates (200 to 200 mkm2) were formed by standard photolithography. Remnant polarization of obtained capacitors reached 5-10 mkC/cm2. Crucial effect of morphological and microstructural deffects of capacitor layers on reproducibility of polarization was noted. Keywords : MOCVD, metallic oxide, ferroelecirics, heterostructures