A method for removing a diffusion barrier layer on pad regions and diminishing the effect of plasma ions induced when removing a photoresist layer by a plasma asher. A two stage rapid thermal processing step is applied to the partially-removed diffusion barrier layer before a metal layer is formed. The first stage lasts a longer period of time at a lower temperature, for example, in the range of between 50 and 60 seconds at a temperature of about 600.degree. C. The second stage lasts a shorter period of time at a higher temperature, for example, in the range of between 20 and 30 seconds at a temperature of about 750.degree. C.