CRYOGENIC ANALYSIS MEASURING THERMAL EXPANSION COEFFICIENT OF SILICON NITRIDE AND SAPPHIRE VIA THE STRAIN GAUGE METHOD AND COMPUTATIONAL SYSTEM COUPLING

Microchip reliability issues can be caused by mismatches in coefficients of thermal expansion (CTE) which can be mitigated by selecting materials with lower thermal expansion values. The strain gauge method was utilized to develop a simple thermal expansion measurement system. The objective of this research is to evaluate the coefficient of thermal expansion of sapphire and silicon nitride within the cryogenic temperature range of 299 K4 K, as alternative options for substrate and printed circuit board (PCB) materials within integrated circuitry. This research focuses on validating experimental results with computational modeling at the liquid nitrogen temperature range of 77K and a brief overview of the mean CTE data at 4K.