Grain growth and twinning in copper thin films for ULSI circuits

摘要

For an analysis of microstructure influence on electromigration behaviour of different deposited copper films, a thorough study of microstructure is necessary. Therefore the temperature dependence of grain growth and twinning of PVD-Cu and the grain growth at room temperature (self-annealing) of electroplating-Cu has been studied. The grain boundaries and the grain size have been measured by backscatter Kikuchi technique (EBSD) and X-Ray Diffraction (XRD). PVD Coppershows a strong <111> fibre texture and electroplating Copper more randomly oriented grains. During the self-annealing of EP-Copper the <111> texture remains but the fraction of randomly oriented cristallites increases. The EBSD data exhibit an accumulation of #SIGMA#3 grain boundaries for both depositions (PVD: 35