How is barium titanate powder made for ceramic capacitors?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Figure 1: Ferroelectric properties of barium titanate (BaTiO3). (Left) Above 120° C the structure of the BaTiO3 crystal is cubic, and there is no net polarization of charge; (right) below 120° C the structure changes to tetragonal, shifting the relative positions of the ions and causing a concentration of positive and negative charges toward opposite ends of the crystal. — capacitor dielectric and piezoelectric ceramics Figure 1: Ferroelectric properties of barium titanate (BaTiO₃). (Left) Above 120° C the structure of the BaTiO₃ crystal is cubic, and there is no net polarization of charge; (right) below 120° C the structure changes to tetragonal, shifting the relative positions of the ions and causing a concentration of positive and negative charges toward opposite ends of the crystal.

Barium titanate powder, which serves as a primary material for ceramic capacitor dielectrics, is produced through two main methods:

Mixing and Firing: The traditional approach involves mixing and firing barium carbonate and titanium dioxide.1
Liquid-Mix Techniques: These methods are increasingly preferred because they allow for better mixing, high purity, submicrometre particle size, and precise control over the barium-to-titanium ratio.1

Once the powder is processed, it is manufactured into capacitors using techniques such as dry-pressing or punching from tape for disk capacitors, or tape casting and doctor blading for multilayer capacitors.1