Study of Thermal and Thermo-Mechanical Behavior in a Multi-Chip-Composed Optoelectronic Package

In this paper, thermal and thermo-mechanical behavior of a multi-chip-composed (MCM) optoelectronic package is analyzed. The optoelectronic module consists of a common silicon platform on which an InP optoelectronic chip and one or more silicon control circuitry chips are flip-chip mounted. The InP chip contains a semiconductor optical amplifier (SOA) which optical gain is temperature sensitive and therefore requires thermal stabilization. The SOA itself generates significant heat flux and, due to the coefficient of the thermal extension (CTE) mismatch between the different package elements, thermo-mechanical stress is generated during device operation. This stress has to be reduced in order to improve the reliability of the packaged system. In our current work, the factors that mostly affect the performance of the SOA thermally and thermo-mechanically i.e. the geometry and count of Au/Sn solder bumps, are analyzed with extensive thermal simulations using Ansoft ePhysicstrade.