In this work, we have investigated the photocurrent and spectral sensitivity of the
silicon/SrTiO3:xNb/perovskite structures. The sol–gel method carried out the deposition of undoped
SrTiO3 layers as well as niobium-doped (SrTiO3:Nb) layers at atomic concentrations of 3 and 6% Nb.
The perovskite layer, CH3NH3PbI3_xClx, has been deposited by the vacuum co-evaporation technique. The layers have been characterized by scanning electron microscopy and X-ray diffraction
measurements. The volt–ampere characteristics and spectral sensitivity of the fabricated samples
have been measured under illumination with selective wavelengths of 405, 450, 520, 660, 780, 808, 905,
980, and 1064 nm of laser diodes. We have shown that for different configurations of applied voltage
between silicon, SrTiO3:xNb, and CH3NH3PbI3_xClx, the structures are photosensitive ones with
a variation of photocurrent from microamperes to milliamperes depending on Nb concentration in
SrTiO3, and the highest photocurrent and spectral sensitivity values are observed when a SrTiO3:Nb
layer with 3 at.% of Nb is used. A possible application of the proposed structure with a SrTiO3:Nb
layer for perovskite solar cells and photodetectors is being discussed