Characterization of conductive heat transfer in electronic device-packages solid systems

摘要

The heat conduction properties of device-package assemblies in electronic system can be experimentally characterised using a method based on the measurement of temperature transient curves after the power switching off. This technique, named TRAIT (Thermal Resistance Analysis by Induced Transient) yield the complete characterisation of row-like equivalent thermal circuit and therefore it allows the knowledge of the total thermal resistance of the system as a sum of several contributions due to the various parts of the assembling structure. This "spatial resolution" may be useful in failure analysis concerning the thermal reliability of multi-layer structures with several layer-layer interfaces. The theoretical background of the method is briefly exposed and some applications to both simulated and real devices are reported in order to demonstrate the capability of the method in revealing the differences of thermal conductive properties due to the parts of a heat conductive chain.