BaTiO3thin films having a perovskite structure were deposited onto stainless steel and fused quartz substrates by sol‐gel processing. Crystalline, transparent, and crack‐free films of 5000 A˚ thickness were fabricated by spinning and post‐deposition annealing at a temperature of 600 °C. Ferroelectric properties were confirmed byP‐Ehysteresis loops. The dielectric constant and optical transmission were also measured.