Studies on electrical properties of PLD grown BiFeO3 - based layered MFIS heterostructure device

Abstract

The pulsed lase deposited layered based thin film heterostructured device have been fabricated in Ag (metal) / Ca doped BiFeO₃ (Ferroelectric) / SrTiO₃ (Insulator) / ZnO (Semiconductor) MFIS geometry on STO (100) single crystalline substrate. The X-ray diffraction measurement confirm the substrate-oriented growth of Ca doped BiFeO₃ and SrTiO₃ layer while growth of ZnO is in different geometry due to its different structure than substrate. Surface and microstructural characterization have been carried out using Atomic Force Microscopy measurements which indicates the homogenous grain growth of Ca doped BiFeO₃ and ZnO layer. Electrical properties of proposed Ca doped BiFeO₃ based MFIS heterostructure have been studied using frequency dependent dielectric, cyclic I-V behaviour (with and without UV illumination) and channel resistance measurements. To understand the electrical property of proposed device, various charge conduction mechanism has understood using the fitting of I-V data. In addition, role of Ca doped BiFeO₃ ferroelectric layer in the channel resistance is investigated.