| Thermal phenomena associated with electronic packaging were introduced and explored in detail. Packaging refers to the silicon integrated circuits (IC), cards and boards. The mechanisms of multi-mode heat transfer in electronic packaging are summarized and approaches to the design and operation by means of conjugate thermal-flow simulations and testing are explored. Simulations were accomplished by numerical modeling with the aid of finite element method (FEM) and finite volume method (FVM) techniques.; The component level designs included the structural design and material management. Structural designs focused on the substrate, die, lid, board, thermal vias, heat sink, adhesive layer design. These configurations are associated with thermal conductivity, convective heat transfer coefficient, emissivity, view factor and other parameters which involve conduction, convection and radiation heat transfer over the IC components, ASICs and other packaging components. Material selections were based on the thermal conductivity performance for IC substrate, die, thermal vias, printed circuit board (PCB), and interfacial materials between heat sinks and lid, die and substrate. A three dimensional (3D) simulation case study of a multi-chip module (MCM) in surface mounted technology (SMT) ball-grid-array (BGA) hybrid packaging on multi-layer printed circuit boards illustrated the component level design.; Device system level designs are mainly associated with forced convection over all components and board level systems. 3D computational fluid dynamics (CFD) FVM models were used to compute system level solutions numerically. These numerical solutions were compared with experimental results. The models involved arrays of electronics modules in a channel.; The simulations involved conduction heat transfer, conjugate conduction/flow, convection and radiation heat transfer. The flows were assumed to be viscous and incompressible laminar or turbulent fluid flow conjugated with heat conduction or radiation. In computational fluid dynamics of system models for turbulence flow, the k-epsilon and LVEL algebraic turbulence models were used. Application of different thermal and flow boundaries including interfacial thermal resistance were explored and a discussion is initiated. The relative error of simulation results were found to lie in the range 0.64%--7.67% in comparison with standard benchmark tests. Future trends of thermal management issues as they apply to electronic packaging are discussed. |
