Fully MOCVD obtained epitaxial ferroelectric capacitors

Abstract

Thin films of ferroelectrics PbZr_xTi_1-xO₃ and metallic oxides La_0.5Sr_0.5CoO₃, LaNiO₃, [La_0.5Sr_0.5CoO₃]_1-x[LaNiO₃]_x were deposited by single source MOCVD using M(thd)_n compounds. After the deposition conditions of individual layers were optimized, the epitaxial capacitors were prepared on MgO single crystal substrates. The series of capacitors with common bottom electrode and separate top electrode plates (200 to 200 μm₂) were formed by standard photolithography and wet etching. Remnant polarization of obtained capacitors reached 5–10 μC/cm² and showed no fatigue behaviour after more then 10¹³ switching. Crucial effect of morphological and microstructural defects of capacitor layers on reproducibility of polarization was noted.

Key Words:

• MOCVD
• metallic oxide
• ferroelectrics
• heterostructures