Failure Mechanism in Thick Film Materials for 300 $~{}^{\circ}{\rm C}$ Operation

Geothermal well logging and instrumentation applications require electronics capable of operation at 300°C. SiC device technology enables the design and fabrication of analog circuits that can operate at these temperatures. However, to build functional systems that can operate at high temperatures, an interconnection and packaging technology must be developed to provide interconnectivity between different SiC devices and passive components. Thick film technology based on metals, glasses, and ceramics has the potential for high operating temperatures. The effect of biased 300°C storage on leakage current and the adhesion of different thick film conductors and multilayer dielectrics has been studied. Mobility of glass modifiers at 300°C has been shown to result in leakage current and adhesion loss.