Investigation of potential and compositional fluctuations in CuGa3Se5 crystals using photoluminescence spectroscopy

Limitation factors for the performance of kesterite Cu2ZnSnS4thin film solar cells studied by defect characterization

“…As shown in Fig. 3(c), a large blue shi of peak energy ($25 meV) with slope of 14.3 meV per decade is observed when excitation density is increased, which is consistent with previous observations 21, [25][26][27][28] in solar cell with large potential uctuations. Actually, the large blue shi with the increasing laser power is one feature of donor-acceptor pair (DAP) transition or band to tail (BT) transition.…”

Study of optical and structural properties of Cu2ZnSnS4 thin films

“…In the low energy side the energy dependence of the PL intensity is exponential whereas in the high energy side the fall of the intensity is steeper. Similar bands with asymmetrical shapes were observed in CZTS grown by other methods [15][16][17][18], as well as, in chalcopyrite-type semiconductors [19][20][21][22][23]. This is the first time PL results are reported for CZTS thin films grown through the sulphurization method.…”

Temperature dependent electroreflectance study of Cu2ZnSnSe4 solar cells

“…An average value of the broadening parameter ΓE125 meV is practically constant over the whole temperature range and one possible explanation is, that not only potential fluctuations, but also the bandgap energy fluctuations due to presence of ordered and disordered structures and/or different defect clusters [5,6,22] are affecting the inhomogeneous broadening. Very similar bandgap energy fluctuations were discovered by PL in the ternary compound CuGa 3 Se 5 [19] and, as a rule, they lead to an abnormal widening of PL and ER bands. Therefore, the bandgap energy E g obtained from ER fittings always represents some average value.…”