Thermal effects on the dielectric and electrical properties of relaxor ferroelectric ceramic-based MLCs

The effects of different thermal shock treatments on dielectric and electrical properties of relaxor based and BaTiO/sub 3/ based "0805" Y5V multilayer ceramic chip capacitors (MLCs) were investigated. It was found that thermal shock generally resulted in larger leakage currents and lower breakdown voltages. It is also confirmed that the thermal shock resistance of relaxer MLCs is in disadvantage to that of the barium titanate MLCs. Nevertheless, no obvious failure was found when the relaxor-based MLCs were subjected to the thermal effects in the normal infrared solder reflow process. Besides the relatively lower mechanical strength, low insulation resistivity and breakdown strength were also proposed to be important contributors to the undesirable reliability of relaxor MLCs.