Pyroelectric response of spray-deposited BaTiO_3 thin film

摘要

Pyroelectric photoresponse of aqueous spray deposited thin films containing BaTiO_3 nano-crystals is reported. X-ray diffraction data indicate the presence of hexagonal BaTiO_3 nano-crystals with ～20 nm crystalline domains in a matrix of some as yet unidentified nano-crystalline material. When the film is annealed at 600 C, the X-ray pattern changes significantly and indicates a conversion to one of the non-hexagonal phases of BaTiO_3 as well as a complete change in the matrix. With suitable amplifier, the measured photoresponse was 40V/W. Ferroelectric hysteresis on a film with significant presence of hexagonal BaTiO_3 shows saturated polarization which is about 5-times smaller than for the bulk tetragonal phase. A potential application is a patternable infrared detector for photonic and plasmonic devices, such as chip-scale spectral sensors.