Bismuth titanate thin film for pressure sensor prepared by sol gel method

Bismuth titanate, Bi₄Ti₃O₁₂ thin film pressure sensor was fabricated by sol gel method. The Bi₄Ti₃O₁₂ thin film was synthesized on substrate Si/ SiO₂ / RuO₂ at low temperature to avoid short-circuit problem. The film was obtained by depositing multiple Bi-Ti-O spin coat layers on substrate, followed by heating of each layer at 300 C in air for 15 mins. Ag film was then deposited as top electrode. The piezoelectric response of the sensor was tested by pneumatic loading method. It was found that the sensor was sensitive to the applied pressure and the response recovered back when the pressure was removed from the chamber. This study showed that the piezoelectric Bi₄Ti₃O₁₂ thin film prepared by sol gel method potentially be used as a stable pressure sensor.