Thin Solid Films, Vol.633, 222-226, 2017
What is the dopant concentration in polycrystalline thin-film Cu(In,Ga)Se-2?
We compare the dopant concentration of polycrystalline Cu(ln,Ga)Se-2 thin film absorbers derived from Hall and capacitance-voltage measurements. Although both measurements techniques appear to be reliable, dopant concentrations determined by capacitance-voltage analysis are significantly lower and vary with probing depth into the absorber. The doping profiles and differences between both measurement techniques are consistent with Cd in-diffusion from the CdS buffer layer during solar cell fabrication. Different doping profiles obtained after a variation of the CdS deposition process support this scenario. (C) 2016 Elsevier B.V. All rights reserved.