Pyroelectric Ba0.8Sr0.2TiO3 thin films derived from a 0.05 M solution precursor by sol–gel processing

Abstract

Tetragonal Ba0.8Sr0.2TiO3 thin films with large columnar grains 100–200 nm in diameter have been prepared on Pt/Ti/SiO2/Si substrates using a 0.05 M solution precursor by sol–gel processing. The ferroelectric phase transition in the prepared Ba0.8Sr0.2TiO3 thin films is broadened, and suppressed to 40 °C with a maximum dielectric constant of εr (100 kHz)=680. The observed low dissipation factor tan δ=2.6% and high pyroelectric coefficient p=4.586×10−4 C/m2 K at 33 °C render the prepared Ba0.8Sr0.2TiO3 thin films promising for uncooled infrared detector and thermal imaging applications.