A new evaluation method of thermal transient measurement results

TLDR

Thermal transient recording is widely used to characterize IC packages, yet the evaluation of the resulting data remains problematic. The article introduces a new mathematical method to evaluate recorded thermal transients. The method computes a detailed heat‑flow map (structure function) and interprets it to reveal package structure. The approach yields a structure function that enables package qualification and defect location, as illustrated by practical examples.

Abstract

Thermal transient recording is a commonly used method for characterization of IC packages. The evaluation of the measured data, however, has involved open questions. The article presents a new mathematical method for the evaluation of the recorded transient. The result of the evaluation is a detailed heat-flow map of the package structure, called the structure function. The paper also deals with the interpretation of this heat-flow map. The final part of the paper discusses practical examples and presents the package qualification and defect location abilities that are inherint in the method.