BaTiO3 Film Grown by Water-Based Process

Autor: Isaiah O. Oladeji, Sarmad Fawzi Hamza Alhasan, Hussain Abouelkhair, Robert E. Peale
Rok vydání: 2016
Předmět:
Zdroj: ECS Transactions. 72:343-349
ISSN: 1938-6737
1938-5862
Popis: Self-assembled nano-crystalline BaTiO3 films on stainless steel foil substrates, were grown by the water based Streaming Process for Electrodeless Electrochemical Deposition (SPEED). SPEED is an aqueous process that deposits self-assembled nanomaterial inorganic thin films over large areas, without a vacuum, providing a scalable and manufacturing friendly process to fabricate durable films. Water-soluble compounds with complexing agents grow films by heterogeneous reaction on the substrate, with little wasteful homogeneous reaction. Hydrophilic substrates bind hydroxyl ions (OH–), which are attachment sites for nucleation with density exceeding 1012 per square centimeter. The water based precursor, nebulized into 10 to 20 μm droplets (vapor phase SPEED, or VPSPEED), impinges on the substrate, which is at temperatures of ~300 ℃, giving growth rate exceeding 200 nm per minute. The substrate heating provides the reaction activation energy, and decomposes/volatilizes reaction byproducts, but the required temperatures are well below those required for spray pyrolysis. All films were subsequently annealed at 500 C for 1 hour. The morphology of the ~1 mm thick films comprises single crystals of micron dimensions imbedded in a matrix of nanocrystals. XRD confirms presence of BaTiO3 crystals of hexagonal phase. Further annealing at 500 oC increases the hexagonal peak intensity. Subsequent annealing at 600 oC for 1 hour causes a substantial transformation to the cubic phase. Potential applications include dielectric layers, capacitors, waveguides, ferroelectric RAM, and pyroelectric infrared detectors and phosphors. Characterization of pyroelectric properties and application to infrared detection will be presented.
Databáze: OpenAIRE
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