Construction, characterization, and reliability of BaTiO3-based buried thick film capacitor materials sets, 1200<K<1600

DuPont investigated an X7R BaTiO₃ based buried thick film capacitor material, K∈(1200, 1600). A capacitor construction methodology is established utilizing various combinations of conductor, high dielectric constant (K) capacitor dielectric, and multilayer insulating dielectric materials. The electrical performance of material sets were characterized by capacitance, dissipation factor, insulation resistance, and temperature change in capacitance. Reliability was ascertained by breakdown voltage, capacitive decay, thermal cycling, voltage bias, HHBT (humidity, voltage bias, and temperature), and capacitance refire stability. In general, for the material sets studied, both low insulation resistance (<10⁹ Ω) and high dissipation factor (df>5%) are positively correlated with low breakdown voltage (<600 V) and can be used as predictors of reliability failure. A new parameter, the reliability quotient, correlates breakdown voltage with capacitance, dissipation factor, and insulation resistance. The optimum materials sets and assembly procedure for reliability and capacitive performance are described