Photoelectric effects in chemical solution deposited Bi₄Ti₃O₁₂ thin films

Abstract

Bismuth titanate ferroelectric thin films were deposited on platinum coated silicon using chemical solution deposition. Photoconductive and photovoltaic effects were observed both in continuous and modulated light. With the increasing of the annealing temperature the maximum of the photoconductive signal spectral distribution is moving toward longer wavelengths, from 340 nm to 370 nm. The existence of the photovoltaic effect could be due to some potential barriers existing at the grain boundaries and the enlargement of its spectral distribution toward longer wavelengths could be due to the presence of some traps at the grain boundaries.