LASER PROBING OF THERMAL-BEHAVIOR OF ELECTRONIC COMPONENTS AND ITS APPLICATION IN QUALITY AND RELIABILITY TESTING

We have developed two optical laser probes for the contactless charact erisation of microelectronic components and ICs. The first is a high r esolution interferometer for the measurement of dilatations, absolute values over 11 decades are obtained ranging from 10(-3) to 10(-14) m. The second is a reflectance probe for the absolute measurement of surf ace temperature variations upon ICs. The instrument is a thermometer f or surface micrometric analysis able to measure temperature variation in the 10(-3) to 500-degrees-K range. The outstanding performances of these probes have been the starting point of the development of new in vestigation methods in the field of quality and reliability measuremen ts. We show results of hot points detection upon integrated circuits w ith micrometric lateral resolution. We also present a method for homog eneity analysis of current density inside power MOS transistors. Final ly we present a method for absolute temperature mapping upon metallic lines used in accelerated tests of current stress to study their relia bility with regard to electromigration.