Reduced leakage current in BiFeO3 thin films with rectifying contacts

TL;DR

This study demonstrates that increasing the growth rate of BiFeO3 thin films near metal contacts reduces leakage current and alters conduction mechanisms, enabling better ferroelectric properties.

Contribution

It reveals that selectively increasing the growth rate near contacts effectively decreases leakage current and improves ferroelectric hysteresis in BiFeO3 films.

Findings

Leakage current decreases with higher growth rates.

Conduction mechanism shifts from Poole-Frenkel to Schottky emission.

Enhanced ferroelectric hysteresis observed.

Abstract

BiFeO3 thin films were grown on Pt/c-sapphire substrates by pulsed laser deposition with different growth rates. With increasing growth rate the leakage current is decreased and the conduction mechanism changes from bulk-limited Poole-Frenkel emission to interface-limited Schottky emission. In the present work, we show that only the growth rate of the BiFeO3 films close to the metal contacts has to be increased in order to reduce the leakage current and to observe saturated polarization-electric field hysteresis loops.