Thermal-mechanical analysis of Terabus high-speed optoelectronic package

Terabus is a high-speed optoelectronic package designed to run at 10-20 Gb/s/channel over 48 channels of optical/electrical links. The Terabus package consists of an optochip that can be passively attached to an optocard with processes similar to those in microelectronic packaging. Due to the high degree of integration, thermal, mechanical, and assembly challenges arise, and need to be addressed. The thermal requirements for the cooling system include handling a heat flux of 60 W/cm², and keeping the vertical-cavity surface-emitting lasers (VCSELs) at a temperature <85 °C. A heat pipe cooling system which satisfies the thermal requirements is designed, assembled and demonstrated. Thermal analysis with finite-element modeling is used to study local temperature distribution in the laser chip. In addition, the model is used to study evolution of stresses in the structure during thermal excursions.