(a) Schematic 3D drawing of one cylindrical grain. For 1D simulations a slice of this grain (green line in (a)) is chosen. (b) Throughout this study a 1D structure with a fixed surface charge and a homogeneous defect density in the bulk (structure A) will be compared with one without a fixed interface charge but with a high defect density at the interface (structure B).
Ratio of the average excess carrier density to the density in the bulk (a), quasi-Fermi level splitting (b) and PC lifetime (c) are shown as a function of the average excess carrier density . Numerical simulations, performed assuming a homogeneous layer with a fixed interface charge (structure A, see Fig. 1 and Table I ), are compared with the semi-analytic model. To highlight the effect of DRM, simulations with and without defects in the SCR and with and without DRM effect are shown.
The black isolines with the labels show the threshold value of excess charge carriers below which the DRM effect starts to dominate the measurement ( ) as function of the band bending and the structure size W. The calculations were performed using the semi-analytic model [Eq. (16) ] and assuming a doping density of for structure A (see Fig. 1 , Table I ).
Ratio of the average excess carrier density to the density in the bulk (a), quasi-Fermi level splitting (b) and PC lifetime (c) as a function of the average excess charge carrier density. The numerical simulations are performed assuming a homogeneous layer with a fixed interface charge. Results for structure A with parameters from Table I are compared with variations in structure size W, fixed charge , doping density and bulk defect density . The injection levels corresponding to illumination with the AM1.5 spectrum are marked.
PC lifetime as a function of the average minority carrier density calculated with numerical simulations for a homogeneous bulk with low defect density and a defective interface (structure B, see Fig. 1 ). Results for structure B with parameters from Table I are compared with variations in GB defect density , defect position and doping density . The injection levels corresponding to illumination with the AM1.5 spectrum are labeled with the corresponding quasi-Fermi level spitting .
(a) PC decay curves of thin poly-Si on glass and on SiN without bias light and with additional bias light with and without 50% NDF. (c) PC lifetime calculated with Eq. (21) . It is highlighted that excess carrier density decreases with time and increases with bias light intensity. Please note that both axes use a logarithmic scale.
Oscillation amplitude of charge carriers during an inductively coupled conductivity measurement as function of distance r between the charge carrier and the coil axis.
Parameters for Structures A and B.
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