Underfilling BGA for harsh environment deployment

A method has been developed to allow use of mainstream commercial low CTE area array IC packages (CBGA) and high CTE area array IC packages (PBGA) side by side on electronics module assemblies intended for deployment in harsh environments such as automotive under-the-hood applications and military avionics applications. The solution leverages composite heatsink technology and underfilling technology to regulate solder joint stresses within acceptable levels. This method does not require any modification to the COTS area array IC packages.