Enhancement of electrical conductivity and lateral photovoltaic sensitivity via mechanical bending in flexible Cr:In2O3 films

Abstract

Functional oxide thin film materials have drawn extensive attention due to their rich tunable properties. Here, we deposited Cr-doped In2O3 thin films on flexible mica substrates and investigated the tunable effect of bending strain on their electrical transport and lateral photovoltaic properties. By applying mechanical bending with different curvature, a range of bending strains from compressive (-0.084%) to tensile (0.083%) in the Cr-doped In2O3 thin films was achieved. As the bending strain increased, the lateral photovoltage based on the thermoelectric effect and the electrical conductivity significantly increased. The flexoelectric effect induced by bending strain plays a key role in the mechanical bending tunable effect. In the Cr:In2O3 thin films, bending strain simultaneously increased both the electrical conductivity and the Seebeck coefficient, while reducing the thermal conductivity, highlighting its potential value in enhancing the performance of thermoelectric materials.