Enhancing reliability with thermal transient testing

Thermal transient measurement, the method for the characterisation of IC packages is gaining increasing importance. The measurement of these transients requires dedicated equipment. The paper discusses the methodology of thermal transient measurements in details, including the compensation of second order effects as non-linearity, non-constant powering etc. In the following part the evaluation methods and algorithmic solutions are discussed. A typical example is presented. Reliability issues are discussed in the last section of the paper, including the problem of die attach testing. The contribution of the thermal transient measurements to the analysis of thermo-mechanical strain is demonstrated.