Processing technologies for ferroelectric thin films and heterostructures

Basic scientific and technological advances on ferroelectric thin films and heterostructures are discussed in relation to the work on nonvolatile ferroelectric random access memories (NVFRAMs) performed by different groups during the last seven years. A reasonable understanding of the synthesis and microstructureproperty relationships of ferroelectric thin films for NVFRAMs is demonstrated. Materials integration strategies developed to fabricate ferroelectric capacitors with practically no fatigue or imprint, long polarization retention, and low leakage current are discussed. These properties have been obtained using two ferroelectric materials, Pb(ZrxTi1-x)O3 (PZT) and SrBi2Ta2O9 (SBT), that are the main candidates for application to the first generation of commercial NVFRAMs. A discussion of current knowledge and future research directions is presented.