Effect of Pt bottom electrode texture selection on the tetragonality and physical properties of Ba0.8Sr0.2TiO3 thin films produced by pulsed laser deposition

TL;DR

This study investigates how the texture of platinum bottom electrodes influences the structural and electrical properties of Ba0.8Sr0.2TiO3 thin films, revealing that electrode orientation affects tetragonality and ferroelectric behavior.

Contribution

It demonstrates the correlation between Pt electrode texture and the tetragonality, dielectric, and ferroelectric properties of BST thin films, highlighting the importance of electrode orientation in device performance.

Findings

Higher tetragonality on (111) textured Pt layers

Polarization current depends exponentially on electric field

Leakage current behavior varies with voltage and Pt texture

Abstract

The effect of platinum (Pt) bottom electrode texture on the tetragonality, dielectric, ferroelectric, and polarization switching response of pulsed laser deposited Ba0.8Sr0.2TiO3 (BST) thin films has been studied. The x-ray diffraction and Raman analysis revealed the higher tetragonality of BST films when they were grown on higher (111) textured Pt layer. The properties like dielectric permittivity, polarization, switching time, and leakage currents were found to be correlated to tetragonality and orientation of the BST films. The polarization current was observed to be higher in BST films on Pt epitaxial layer and it exhibits exponential dependence on the electric field. The voltage-current measurements displayed Ohmic behavior of leakage current irrespective of Pt texture for low voltages (up to 1 V), whereas at higher voltages the conduction mechanism was found to be dependent on texture selection of bottom Pt electrode.