Surface treatment of CuInGaSe2 thin films and its effect on the photovoltaic properties of solar cells Original Research Article

Solar cells have been fabricated with partial electrolyte treatments of CuInGaSe2 (CIGS) thin film absorbers in lieu of a CdS layer. Treatment of the absorbers in a Cd or Zn containing solution is shown to produce conditions under which efficient solar cells can be fabricated. A similar effect is also observed in CuInGaSSe2 (CIGSS) graded band gap absorbers. These observations can be explained by the ability of Cd and Zn to produce n-type doping or inversion in the surface region. We also provide a brief review of similar work done elsewhere and identify directions for future investigations.