Published online by Cambridge University Press: 25 February 2011
The thermal stability at the Cu / SiO2 interface has been studied as a function of the annealing atmosphere composition. Using either good vacuum conditions or refractory metal encapsulation, no copper diffusion into SiO2 has been found even for thermal treatments at 500°C for l0h. Moreover, a noticeable accumulation of the refractory metal, ( Cr, Ti ), at the Cu / SiO2 interface has been observed. The diffusion phenomena allows the self-aligned formation of a refractory metal barrier layer at the SiO2 surface.