Microwave Dielectric Properties and Low‐Temperature Cofiring of BaTe ₄ O ₉ with Aluminum Metal Electrode

Abstract

Polycrystalline BaTe 4 O 9 ceramic compound was investigated as a promising microwave dielectric compound for low‐temperature cofired ceramics (LTCC) applications. The binary phase BaTe 4 O 9 was synthesized and subsequently densified over the temperature range of only 500°–550°C, which allows for low‐temperature cofiring with aluminum metal. The dielectric properties of BaTe 4 O 9 ceramics sintered at 550°C for 2 h were determined in the microwave region of 12–14 GHz. The dielectric constant and Q × f product obtained were 17.5 and 54 700 GHz at 12 GHz, respectively. The temperature coefficient of resonance frequency showed a negative value of −90 ppm/°C. In terms of its evaluation for LTCC, the BaTe 4 O 9 composition was found to be chemically compatible and successfully cofired with highly conductive aluminum electrode, while maintaining good electrical performance.