Diffusion and incorporation of Cd in solar-grade CIGSe layers

Hiepko K., Bastek J., Stolwijk N.A., Schlesiger R., Schmitz G., Wuerz R.

Abstract

We examined Cd diffusion in Cu(In,Ga)Se2 layers by means of the radiotracer technique. Depth profiles of 109Cd were determined by ion-beam sputter-sectioning upon isothermal diffusion in the range from 197 to 425 o C. The Cd diffusivity can be described by the Arrhenius equation DCd ¼ 4.8 x 10-4 exp (-1.04 eV/kBT )cm2s-1. Atom-probe tomography on a sample saturated with natural Cd at 450 oC revealed its homogeneous incorporation over the crystal volume.