GROWTH AND FRACTAL SCALING NATURE OF COPPER THIN-FILMS ON TIN SURFACEBY METAL-ORGANIC CHEMICAL-VAPOR-DEPOSITION FROM HEXAFLUOROACETHYLACETONATE CU-(I) VINYLTRIMETHYLSILANE

The initial stage of growth and fractal scaling nature of copper (Cu) films, deposited by metal organic chemical vapor deposition on TiN sub strate using hexafluoroacethylacetonate Cu(I) vinyltrimethylsilane pre cursor, was investigated by means of Auger electron spectroscopy, atom ic force microscopy (AFM), x-ray diffraction, transmission electron mi croscopy, and scanning electron microscopy (SEM). Cu films were deposi ted in the surface reaction controlled regime (< 200 degrees C) onto a columnar structure TIN substrate and discontinuous island growth was observed due to oxygen contamination of the TiN surface. Preferred ori entation of the deposited Cu film changed as a function of the deposit ion time and coverage. The roughness exponent (alpha) and lateral corr elation length (xi) of Cu films grown under different growth stages we re studied. From AFM measurement, it was found that the roughness expo nent increased with increasing deposition time and the lateral correla tion length also increased as the grains coalesced, which was also com pared with SEM images. For island growth mode at the early stage of gr owth, alpha was below 0.65 and it saturated at 0.75 for the continuous growth mode. (C) 1997 American Vacuum Society.