title: Microscopic evidence for the modification of the electronic structure at grain boundaries of Cu(In(1-x),Ga(x))Se2 films.
abstract: We investigated the electronic properties around grain boundaries of polycrystalline Cu(In(1-x),Ga(x)Se(2)) films as a function of Ga content, using scanning tunneling spectroscopy. Spectra acquired on samples with low Ga content (x=0 and 0.33) reveal downward band bending with respect to adjacent p-type grains, suggesting type inversion at the surface of grain boundaries. Such a behavior was not observed for samples with high Ga contents. These results are consistent with our atomic force microscopy data and may shed light on the origin of the x-dependent efficiency for polycrystalline Cu(In(1-x),Ga(x)Se(2))-based solar cells.
authors.affiliation: Racah Institute of Physics and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Doron
authors.initials: D
authors.lastname: Azulay
authors.forename: Isaac
authors.initials: I
authors.lastname: Balberg
authors.forename: Oded
authors.initials: O
authors.lastname: Millo