A new approach to modelling Kelvin probe force microscopy of hetero-structures in the dark and under illumination

A numerical method is proposed to model Kelvin probe force microscopy of hetero-structures in the dark and under illumination. It is applied to FTO/TiO 2 and FTO/TiO 2 /MAPbI 3 structures. The presence of surface states on the top of the TiO 2 layers are revealed by combining theoretical computation and experimental results. Basic features of Kelvin probe force microscopy under illumination, namely surface photovoltage, are simulated as well. The method paves the way toward further investigations of more complicated optoelectronic devices.