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Updated: Jan 26, 2026

Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
Conduction mechanism and switchable photovoltaic effect in (1 1 1) oriented BiFe0.95Mn0.05O3 thin film
J Belhadi1, J Ruvalcaba2, S Yousfi1
1LPMC EA2081, Université de Picardie Jules Verne, 33 Rue Saint Leu, 80000 Amiens, France.
None:
Epitaxial 200 nm BiFe0.95Mn0.05O3 (BFO) film was grown by pulsed laser deposition (PLD) on (1 1 1) oriented SrTiO3 substrate buffered with a 50 nm thick SrRuO3 electrode. The BFO thin film shows a rhombohedral structure and a large remnant polarization of Pr = 104 µC cm-2. By comparing I(V) characteristics with different conduction models we reveal the presence of both bulk limited Poole-Frenkel and Schottky interface mechanisms and each one dominates in a specific range of temperature. At room temperature (RT) and under 10 mW laser illumination, the as grown BFO film presents short-circuit current density (J sc) and open circuit voltage (V oc) of 2.25 mA cm-2 and -0.55 V respectively. This PV effect can be switched by applying positive voltage pulses higher than the coercive field. For low temperatures a large V oc value of about -4.5 V (-225 kV cm-1) is observed which suggests a bulk non-centrosymmetric origin of the PV response.
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