@ARTICLE{Barreau_solmat_2009,
  author = {N. Barreau and J. L\"ahnemann and F. Couzini\'e-Devy and L. Assmann
	and P. Bertoncini and J. Kessler},
  title = {Impact of {Cu}-rich growth on the {CuIn$_{1-x}$Ga$_x$Se$_2$} surface
	morphology and related solar cells behaviour},
  journal = Sol. Energ. Mat. Sol. C.,
  year = {2009},
  volume = {93},
  pages = {2013--2019},
  number = {11},
  abstract = {The amount of copper excess provided during the Cu(In,Ga)Se2 (CIGSe)
	3-stage co-evaporation process is among the most operator subjective.
	In the present paper the influence of this parameter on the properties
	of the CIGSe films as well as on the behaviour of the related solar
	cells is investigated. It is observed that both the In/Ga lateral
	intermixing and the grain size are enhanced when the excess of copper
	is increased. Contrary to what could be expected, these changes only
	weakly affect the performance of the solar cells. Increasing the
	copper excess also yields a rougher CIGSe morphology. This latter
	evolution is observed to be the most important factor influencing
	the device behaviour. Through accurate analysis of quantum efficiency,
	it is concluded that, in the case of the standard cell structure,
	there exists a threshold in copper excess, beyond which the cell
	performance is significantly reduced.},
  doi = {10.1016/j.solmat.2009.08.004},
  keywords = {CIGSe}
}