CdCl Treatment-Induced Enhanced Conductivity in CdTe Solar Cells Observed Using Conductive Atomic Force Microscopy.

The rear surfaces of CdTe photovoltaic devices without back contacts, grown by close-spaced sublimation (CSS), were analyzed using conductive atomic force microscopy (C-AFM). As-deposited and CdCl-treated CdTe samples were compared to clarify the effect of the treatment on charge flow through grains and grain boundaries. The CdCl-treated samples exhibit a more homogeneous and enhanced current flow across the grains as compared to the as-deposited samples.