Glancing-angle X-ray diffraction and X-ray photoelectron spectroscopy studies of nitrogen-implanted tantalum

Composition of tantalum nitride thin films grown by low-energy nitrogen implantation: a factor analysis study of the Ta 4 f XPS core level

“…Raole et al [13] have suggested that preferential nitrogen loss during 30keV nitrogen implantation of tantalum is responsible for the formation of the low-stoichiometry Ta 2 N phase at higher ion doses (~5x10 17 atoms/cm 2 ) due to the reduction of cubic TaN and hexagonal Ta 5 N 6 phases previously formed. According to results of Table 2, the nitrogen sputtering yield, S y N , at saturation does not depend markedly on the ion beam energy between 0.5 and 5keV.…”

“…Finally, for the heaviest nitrogen dose (~5x10 17 atoms/cm 2 ), XRD analysis shows the presence of β-TaN 0.05 , γ-Ta 2 N, δ-TaN and ε-TaN phases. Raole et al [13] have found that β-TaN 0.05 , cubic TaN and hexagonal Ta 5 N 6 phases are formed for low nitrogen ion doses, however, the hexagonal γ-Ta 2 N and TaN phases are only observed for higher ion doses.…”

“…Ensinger et al [2] and Zhang et al [3], have shown using IBAD with nitrogen ions of 25 to 70keV and XRD, that the tantalum nitride films formed consist of a metastable cubic TaN phase. On the other hand, Zhou et al [12] and Raole et al [13] have studied the growth of tantalum nitride films by nitrogen implantation at 80 and 30keV, respectively. According to Zhou et al [12], there is a correlation between the types of nitrides formed and the ion dose.…”

“…Moreover, alternative techniques like ion beam assisted deposition (IBAD) [1][2][3][4] and nitrogen implantation [12][13][14]16,17], that allow the growth of the film keeping the substrate at low or moderate temperatures, have been also used recently by several groups.…”

“…The synthesis and characterisation of tantalum nitride thin films have attracted great interest during the last years due to their different technological applications, especially as protective hard coatings and diffusion barriers in copper metallizations [1][2][3][4][5][6][7][8][9][10][11][12][13][14].…”