Direct Write Extreme Environment Packaging

There is growing interest in extreme temperature electronics to support instrumentation for sensors at temperatures beyond the normal range of electronics. Reliable packaging in the temperature range of more than 300°C has been demonstrated using ceramic multi-chip modules using conventional hybrid circuit technology. This approach typically requires high NRE costs and lead time. Additive manufacturing processes of metals, ceramics, conductors, and dielectrics provides a digital transformation of hybrid circuit manufacturing technology that reduces time and cost for packaging with the added benefits of novel 3D structures and embedded features. Silicon carbide devices have been demonstrated to operate above 300C which requires capable interconnects. This report presents the results of testing to characterize important electrical and mechanical properties of additively manufactured packaging materials (substrates, conductor, dielectrics) and die interconnect methods capable for operation above 300 °C. Characterization of thick film materials were tested for resistance, SIR, and adhesion stability on 96% alumina, 98.4% additively printed alumina, and Corning alumina ribbon ceramic at 300, 500, and 750°C. Methods for direct write interconnects were developed and tested at 300 and 500C for resistance stability and thermal shock. The methods are direct write surface interconnects, embedded interconnects using additive alumina substrates, and flip chip. Reliability testing results, a test method for insitu measurement, and demonstrations using the materials are presented.