Fabrication and characterization of Au/SBT/LZO/Si MFIS structure

Abstract

Ferroelectric SrBi 2 Ta 2 O 9 (SBT) films on a ptype Si (100) wafer with a LaZrO x (LZO) buffer layer have been fabricated to form a metal-ferroelectric-insulatorsemiconductor (MFIS) structure. The LZO thin film and SBT films were deposited by using a sol-gel method. The equivalent oxide thickness (EOT) value of the LZO thin film was about 8.83 nm. Also, the leakage current density of the LZO thin film is about 3.3×10 −5 A/cm 2 at bias sweeping voltage of ±5 V. SBT films were crystallized in polycrystalline phase with highly preferred (115) orientation. Also, the intensity of each pick slightly increased as thickness of SBT films increased. The C-V characteristics of Au/SBT/LZO/Si structure showed clockwise hysteresis loop. The memory window width increased as the thickness of SBT films increased. The leakage current density of Au/ SBT/LZO/Si structure decreased as thickness of SBT films increased.