What microchip stress testing can teach us Press enter or click to view image in full size Photo by Ged Mullen-Buick on Unsplash Not a Medium member? Read here . Before microchips reach our computers and smartphones, they are put through accelerated reliability stress testing to ensure their intended lifespan. Human aging, in many ways, is also a reliability challenge. Reliability of chips strongly depends on stress conditions, such as environmental humidity, elevated power, hot-cold temperature swings, and the number of cycles. The harsher the environment, the shorter their lifespan. External stress also interacts with the device’s internal stress condition, weakening components over time. Take thermal-mechanical stress as an example. Since different materials, i.e., Si, copper, dielectrics, and polymers, are used to build microchips, differences in material properties create residual stress during processing within chips. The internal stress directly influences its long-term structural integrity.…