Fabrication and characterization of metal-ferroelectric (PbZr0.53Ti0.47O3)-insulator (Dy2O3)-semiconductor capacitors for nonvolatile memory applications

Metal-ferroelectric-insulator-semiconductor capacitors with Pb(Zr0.53,Ti0.47)O3 (PZT) ferroelectric layer and dysprosium oxide (Dy2O3) insulator layer were fabricated and characterized. The measured memory window of 0.86V was close to the theoretical value ΔW≈2dfEc≈0.78V at a sweep voltage of 8V. The size of the memory window as a function of PZT film thickness was discussed. The C-V flatband voltage shift (ΔVFB) as function of charge injection was also studied. An energy band diagram of the Al∕PZT∕Dy2O3∕p-Si system was proposed to explain the memory window and flatband voltage shift. The charge injection is mainly due to electrons.