1st Paragraph: Thermal fatigue is a common cause of failure in electronic interconnects and therefore electronic devices. One of the issues of investigating the reliability of a device against failure through thermal fatigue is that this process requires thermal cycling, which is a slow process. Thermal cycling causes stresses in the material through differential thermal expansion, which depends on thermal gradients in the device, as well as differences in co-efficient of thermal expansion (CTE). If the thermal cycling rate is increased to a high rate, then the stresses generated in the device are not representative of the stresses that would be generated at a lower cycling rate, due to the finite rate of thermal conductivity and a thermal shock process may occur instead of the expected thermal cycling .
Authors: David Routledge and Tae-Kyu Lee
Keywords: Solder characterization, thermal cycling, failure investigation, solder fatigue