Ion beam preparation of passivated copper integrated circuit structures for electron backscatter diffraction/orientation imaging microscopy analysis

Passivation layers were removed from copper interconnect lines using a broad beam ion source in preparation for electron backscatter diffraction (EBSD) and orientation imaging microscopy (OIM) analysis. Results were obtained on interconnect lines with widths as small as 0.25 μm. The effects of ion beam energy and scanning electron microscope (SEM) acceleration voltage on the quality of the results obtained are examined and explained. The use of thin amorphous carbon coatings to reduce specimen charging during orientation data collection is also discussed.