Thermal Testing of Integrated Circuits

Temperature has been always considered as an appreciable magnitude to detect failures in electric systems. In this book, the authors present the feasibility of considering temperature as an observable for testing purposes, with full coverage of the state of the art.Temperature has been always considered as an appreciable magnitude to detect failures in electric systems. Abnormal status of this variable, both too high and too low, is sign of abnormal behavior in electronic systems. In Thermal Testing of Integrated Circuits the authors present the feasibility to consider temperature as an observable for testing purposes. The coupling of circuits through heat is inherent to the solid-state nature and the inspection of temperature does not interact with Under Test Circuits or Systems, something that does not happen when voltage or current observable are used. In the book the basis of heat propagation, heat conducting mechanisms and temperature sensitivity of semiconductors are focused with a full coverage of the state of the art. We usually have the idea that all the heating processes are slow, which is true in the macroscopic world, but is not in the case of integrated circuits where the reduced size and amount of material and the really high conductivity of substrates make the thermal testing a promising technique. CMOS and BICMOS temperature sensors for built-in thermal testing are presented in the book. The application of temperature as testing magnitude for both on-line and off-line, analog or digital, on-chip or off-chip are considered. The temperature sensing has an inherent directional capability that can be used as an element for localizing failures, so the technique has interesting diagnosis capabilities as well.