CAPTEUR DE CONTRAINTE APPROPRIÉ POUR MESURER UNE CONTRAINTE MÉCANIQUE DANS UNE STRUCTURE DE MÉTALLISATION EN COUCHES D'UN COMPOSANT MICROÉLECTRONIQUE

摘要

The invention is related to a sensor for measuring mechanical stress in a layered metallization structure such as the back end of line portion of an integrated circuit die. The sensor operates as a field effect transistor comprising a gate electrode (1), gate dielectric (5), channel (6) and source and drain electrodes (7,8), wherein the gate electrode is a conductor (1) of a first metallization level and the source and drain electrodes are two interconnect vias (7,8), connecting the channel (6) to respective conductors (3,4) in an adjacent level. At least one of the interconnect vias is formed of a material whereof the electrical resistance is sensitive to mechanical stress in the direction of the via. The sensitivity of the electrical resistance to the mechanical stress is sufficient to enable measurement of the stress by reading out the drain current of the transistor. The sensor thereby allows monitoring of stress in the BEOL prior to cracking.