1.
S Reiter; N Koper; R Reineke-Koch; Y Larionova; M Turcu; J Krügener; D Tetzlaff; T Wietler; U Höhne; J -D Kähler; R Brendel; R Peibst
Parasitic Absorption in Polycrystalline Si-layers for Carrier-selective Front Junctions Artikel
In: Energy Procedia, Bd. 92, S. 199-204, 2016, ISSN: 1876-6102, (Proceedings of the 6th International Conference on Crystalline Silicon Photovoltaics (SiliconPV 2016)).
@article{Reiter2016d,
title = {Parasitic Absorption in Polycrystalline Si-layers for Carrier-selective Front Junctions},
author = {S Reiter and N Koper and R Reineke-Koch and Y Larionova and M Turcu and J Krügener and D Tetzlaff and T Wietler and U Höhne and J -D Kähler and R Brendel and R Peibst},
doi = {10.1016/j.egypro.2016.07.057},
issn = {1876-6102},
year = {2016},
date = {2016-08-01},
journal = {Energy Procedia},
volume = {92},
pages = {199-204},
abstract = {We investigate the optical properties of n- and p-type polycrystalline silicon (poly-Si) layers. We determine the optical constants n and k of the complex refractive index of polycrystalline silicon by using variable-angle spectroscopic ellipsometry. Moreover, we investigate the effect of different doping levels in the poly-Si on free carrier absorption (FCA). Thereby, we demonstrate that the FCA in poly-Si can be described by a model developed for crystalline silicon (c-Si) at a first approximation. The optical properties of hydrogenated amorphous silicon layers (a-Si:H) are also investigated as a reference. With ray tracing simulations the absorption losses of poly-Si and of the a-Si:H layers are quantified with respect to the film thickness. Based on this approach we find that the short-circuit current density losses due to parasitic absorption of poly-Si layers are significantly lower when compared to a-Si:H layers of the same thickness. For example the short-circuit current density loss due to a 20 nm thick p-type poly-Si layer is around 1.1 mA/cm2, whereas a 20 nm thick p-type a-Si:H layer leads to a loss of around 3.5 mA/cm2.},
note = {Proceedings of the 6th International Conference on Crystalline Silicon Photovoltaics (SiliconPV 2016)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We investigate the optical properties of n- and p-type polycrystalline silicon (poly-Si) layers. We determine the optical constants n and k of the complex refractive index of polycrystalline silicon by using variable-angle spectroscopic ellipsometry. Moreover, we investigate the effect of different doping levels in the poly-Si on free carrier absorption (FCA). Thereby, we demonstrate that the FCA in poly-Si can be described by a model developed for crystalline silicon (c-Si) at a first approximation. The optical properties of hydrogenated amorphous silicon layers (a-Si:H) are also investigated as a reference. With ray tracing simulations the absorption losses of poly-Si and of the a-Si:H layers are quantified with respect to the film thickness. Based on this approach we find that the short-circuit current density losses due to parasitic absorption of poly-Si layers are significantly lower when compared to a-Si:H layers of the same thickness. For example the short-circuit current density loss due to a 20 nm thick p-type poly-Si layer is around 1.1 mA/cm2, whereas a 20 nm thick p-type a-Si:H layer leads to a loss of around 3.5 mA/cm2.