Effect of SrTiO3 buffer layer on electrical, ferroelectric memory, and polarization reversal studies of spin-coated ferroelectric 0.6Ba (Zr0·2Ti0.8)O3-0.4(Ba0·7Ca0.3)TiO3 thin film in MFIS structure

Abstract

This work highlights the effect of SrTiO3 (STO) buffer layer on leakage current, memory, and polarization reversal properties of spin-coated 0.6Ba(Zr0·2Ti0.8)O3-0.4(Ba0·7Ca0.3)TiO3 (BCZT) thin film on Si-substrate in metal-ferroelectric-semiconductor configuration. XRD and Raman analysis confirm the presence of a morphotropic phase of BCZT. Raman and SEM studies suggested that STO enhances the microstructure of BCZT films. The current-voltage (I–V) analysis suggests that the transport mechanism is governed by Schottky – emission model and insertion of STO reduces the leakage current by three orders of magnitude. The capacitance-voltage (C–V) characteristics of Al/BCZT/Si and Al/BCZT/STO/Si structures exhibited a memory window of 1.7 V and 2.6 V respectively. The Al/BCZT/STO/Si structure also showed good retention properties. Further, the peak values of polarization current in the Al/BCZT/STO/Si structure exhibited Mert'z law. The low leakage current, enhanced memory window, high retention characteristics, and faster switching time of the Al/BCZT/STO/Si structure make it attractive for next-generation memory applications.