Textural evolution of Cu interconnects having a different line width was
investigated after annealing. Texture was measured on the surface of Cu
interconnects using EBSD (electron backscattered diffraction) techniques
including GBCD (grain boundary character distribution). To analyze a
relationship between the stress distribution and textural evolution in the
samples investigated, the micro stresses were calculated for the different
line width at 200°C using FEM (finite element modeling). In this
investigation, it was found that the inhomogeneity of stress distribution in
Cu interconnects is an important factor is necessary for understanding
textural transformation after annealing. A new interpretation of textural
evolution in damascene interconnects lines after annealing is suggested,
based on the state of stress and the growth mechanisms of Cu
electrodeposits.