화학공학소재연구정보센터
Thin Solid Films, Vol.487, No.1-2, 8-13, 2005
Lateral variations of optoelectronic quality of Cu(In1-xGax)Se-2 in the submicron-scale
Optoelectronic properties of Cu(In1-xGax)Se-2 (CIGSe) have been studied by confocal microscopic photoluminescence (PL)with lateral submicron resolution. The lateral patterns of PL-yields, varying by factors of up to 10 between regimes with low and high emission, exhibit structures in the length scale of some micrometers (3-10 mu m) whereas geometrical sizes of individual grains are in the 1-mu m range or below. In addition to the local PL-variation, we observe that the geometrical extension of PL-patterns depend on excitation flux, that spectral PL-shapes are varying with respect to different onset energies of the low-energy wings, signalizing different local band gaps and that low-energy PL-wings get steeper with rise in excitation flux pointing towards potential fluctuations and their respective screening by photoexcited excess carriers. (C) 2005 Elsevier B.V. All rights reserved.