CONTRIBUTION OF THE TEMPERATURE-MEASUREMENT USING THERMOELECTRICAL MICRO-PROBE IN THE FIELD OF THERMAL MICROSCOPY

New non destructive investigation techniques by means of photoacoustic and photothermal phenomena have appeared and are growing up for more than 15 years. The low thermal inertia of thermoelectrical microprobes allows the detection of thermal waves produced around an absorbing surface heated by a modulated laser beam. It is possible to measure thermal characteristics of thin samples in transmission mode. On the other hand, the thermal microscopy can be operated in the reflection mode for surface imaging or microcircuit defects detection; in this case the lateral resolution is given by the excitation beam diameter (a few micrometers).