ABSTRACT
Energy-loss imaging in the transmission electron microscope has been used to characterise localised changes in the densities and compositions of porous low k dielectric oxides formed by different types of optimised resist strip processing. Optimised resist strip processes have been used to 'seal' the sidewalls of porous dielectric oxides, but little is known about their effects on the microstructure of low k dielectric oxides. The bands are similar for each resist strip process, have a typical width of between 5 and 8 nm, and exhibit stronger absorption contrast than the oxides located to their sides. The line scans show that the N 2/H 2 treatment results in an increase in the density of both C and 0 within the sidewall regions of the dielectric layers, when projected in the electron beam direction, relative to that in the N2/02 stripped sample.
