Thermal-mechanical analysis of packaged power amplifiers based on heterogeneous integrations using photosensitive BCB

This study demonstrated the fabrication integration process of two cascaded GaAs MMICs using BCB films in order to achieve heterogeneous integration. Thermal-mechanical analysis has been simulated and performed to investigate the distributions of the temperature and stress. It has been found that the maximum temperature in the packaging depended on the dissipated power of the RF medium power amplifier. Although the temperature would not exceed the channel temperature of the dies in this case, the materials may also exceed their yield strength which will cause the reliability issues. This research will help to understand significant thermal and mechanical issues of high density IC packaging.