Barium titanate (BaTiO3) semiconductors' introduction

Barium titanate is an inorganic compound with the chemical formula BaTiO3. It is a white powder that is transparent as larger crystals. This titanate is a ferroelectric ceramic material, having piezoelectric properties and a photorefractive effect. It can exist in five phases including hexagonal, cubic, tetragonal, orthorhombic, and rhombohedral crystal structure. All the phases exhibit the ferroelectric effect except the cubic phase. It can be manufactured by heating barium carbonate and titanium dioxide. 

Applications

Barium titanate is a dielectric ceramic used for capacitors. 

As a piezoelectric material, it was largely replaced by lead zirconate titanate but has been widely used in microphones and other transducers. 

Polycrystalline barium titanate exhibits a positive temperature coefficient, which makes it a useful material for thermistors and other self-regulating electric heating systems. 

Barium titanate material can be operated at visible and near-infrared wavelengths and has high beam-coupling gain, and hence it is widely used for self-pumped phase conjugation applications. 

The material is doped with various other elements like iron for photorefractive applications. 

The pyroelectric and ferroelectric properties of barium titanate enable it to be used in uncooled sensors of thermal cameras.