Characteristics of ferroelectric SrBi₂Ta₂O₉ thin films grown by “flash” MOCVD

Abstract

Abstract A chemical vapor deposition process for the ferroelectric SrBi2Ta2O9 has been developed utilizing a liquid delivery and flash vaporization technique. Uniform layered perovskite of SrBi2Ta2O9 was formed over 4 inch wafers by the chemical vapor deposition followed by annealing at 800°C in oxygen ambient. The SrBi2Ta2O9 thin film capacitors showed well saturated hysteresis loops with remanent polarization (2Pr) and coercive field (Ec) of up to 21.3 (μC/cm2) and 47.2 (kV/cm), respectively. The SrBi2Ta2O9 capacitors with platinum electrodes showed fatigue free characteristics after switching of 1×1010 cycles. The chemical vapor deposition technique demonstrated excellent conformal coating of SrBi2Ta2O9 film on 0.5 μm line-and-space patterns. These performances will meet the requirements for high-density nonvolatile memory devices.