Fatigue-free La-modified Pb(Zr, Ti)O3 capacitors using aseed layer

Abstract

The development of lead zirconate titanate (PZT)-based capacitors using common Pt electrodes has been a long-time goal of ferroelectric random access memories (FRAM).In this work, a series of Pb1−xLax(Zr0.55Ti0.45)O3 capacitors (for 0.01 < x < 0.05) having fatigue-free characteristics have been grown on Pt/ Ti/SiO2/Si substrates. Typically 2–3 mol% La-modified PZT capacitors fabricated at 580 °C by applying a PZT seed layer exhibited fatigue-free behavior up to 6.5 × 1010 switching cycles, a low coercive field of 50–55 kV/cm, and a stable charge retention profile with time, all of which assure their suitability for the future nonvolatile FRAM.