The Failure analysis plays an important role in the improvement of the performances and themanufacturing of integrated circuits. Defects can be present at any time in the product chain,during the conception (design), during the qualification, during the production, or still duringits use. It is important to study these defects in order to improve the reliability of the products.Furthermore, with the density increasing and the complexity of the chips, it is harder andharder to localize the defects. This thesis work consists to develop a new failure analysis technique based on the study of thereflected laser beam the "Laser Voltage Imaging" LVI, for the ultimate technologies (below45nm).