In a high efficiency CIGS solar cell, we observed a MoSe2, layer at the int
erface by SIMS, TEM and X-ray diffraction, MoSe2, had a layer structure and
the layers were oriented perpendicular to the Mo layer. The MoSe2, contrib
utes to the improvement of adhesion at the CIGS/Mo interface. The effects o
f the MoSe2, layer on the electrical and photovoltaic properties of CIGS so
lar cells were investigated. The CIGS/Mo heterocontact, including the MoSe2
, layer, is not Schottky-type, but a favorable ohmic-type by the evaluation
of dark I-V measurement at low temperature. A characteristic peak at 870 n
m is observed in the differential quantum efficiency of a solar cell with a
CIGS thickness of 500 nm. This peak relates to the absorption of the MoSe2
layer. The band gap of MoSe2, is calculated to be 1.41 eV from the absorpt
ion peak. (C) 2001 Elsevier Science S.V. All rights reserved.