Chapter 1. Synthesis of Single Phase (Ba,Sr)TiO₃, by a Reactive Process

Summary

This work utilized an energy-efficient reactive process to produce sputtering targets made out of (Ba,Sr)TiO₃ (BST). BST and related materials such as BaTiO₃ (BT) and SrTiO₃ (ST) (in thin film conditions) are important constituents for future generation computer chips. Because of their high dielectric constant, they are likely to be used as capacitors in dynamic random access memory devices (DRAMS). The reactive process utilized here is the “Microwave Activated Combustion Synthesis (MACS)”. The reactants BaO, BaO₂, TiO₂, SrO₂, and Ti were mixed in proper ratios and reacted in situ inside a commercial microwave furnace. For comparison, same reactants were ignited in a conventional sintering furnace and results were compared. The constituents were chosen based upon the thermodynamic calculations. The phases were evaluated by X-ray diffraction technique (XRD). Microstructures were characterized by a scanning electron microscope (SEM). The results showed that pure single phase BST can be formed by MACS process.