Structural and dielectric properties of glasses in the system TeO2-CaCu3Ti4O12

TL;DR

This study investigates the structural and dielectric properties of TeO2-CaCu3Ti4O12 glasses, revealing their amorphous nature, temperature-independent dielectric behavior, and potential for high-frequency electronic applications.

Contribution

It presents new insights into the dielectric and structural characteristics of TeO2-CaCu3Ti4O12 glasses, highlighting their low loss and thermal stability for high-frequency device substrates.

Findings

Dielectric constant increases with CCTO content.

Loss remains low and nearly constant across frequencies.

Glasses exhibit high thermal stability and amorphous structure.

Abstract

The glasses in the system (100-x)TeO2-xCaCu3Ti4O12, (x=0.25 to 3 mol %) were fabricated. The color varied from olive green to brown as the CaCu3Ti4O12 (CCTO) content increased in TeO2 matrix. The X-ray powder diffraction and differential scanning calorimetric analyses that were carried out on the as-quenched samples confirmed their amorphous and glassy nature respectively. The dielectric constant and loss in the 100 Hz-1MHz frequency range were monitored as a function of temperature (50-400oC). The dielectric constant and the loss (D) increased as the CCTO content increased in TeO2 at all the frequencies and temperatures under investigation. Further, the effective dielectric constant and D were found to be frequency independent in the 50-200oC temperature range. The value obtained for the loss at 1MHz was 0.0019 which was typical of low loss materials, and exhibited near constant loss (NCL) in the 100Hz-1MHz frequency range. The electrical relaxation was rationalized using the electric modulus formalism. These glasses may be of considerable interest as substrates for high frequency circuit elements in conventional semiconductor industries owing to their high thermal stability.