Preparation of low-loss titanium dioxide for microwave frequency applications

Preparation of low-loss titanium dioxide for microwave frequency applications Conference

Zhang, L, Shqau, K, Verweij, H et al. (2008). Preparation of low-loss titanium dioxide for microwave frequency applications . 1 94-101.

Dense titanium dioxide (TiO2) was prepared from commercially available high-purity powders. The powders were first deagglomerated and colloidally stabilized in aqueous NH3 to form a stable suspension. The suspension was screened, followed by colloidal-filtration, drying and sintering. Sintering at 1000°C for 10 hours resulted in > 99.5% density and 2.2 μm grains. The dielectric loss of the dense-sintered TiO2 was 1.4X10-4 at 6.4 GHz at room temperature. This low dielectric loss is attributed to a low sintering temperature and homogeneous microstructure. Dense, low-loss TiO2 is particularly interesting for microwave applications because of its very high dielectric constant at GHz frequencies. The process presented here will be used to make dense TiO2 parts with complex shape in new microwave antenna concepts, for its high dielectric constant and low dielectric loss at microwave frequencies. © 2008 MS&T'08 ®.