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This work presents the results of a detailed series resistance characterization of silicon solar cells with screen-printed front contacts using hotmelt silver paste. Applying the hotmelt technology energy conversion efficiencies up to 18.0% on monocrystalline wafers with a size of 12.5 cut X 12.5 cut have been achieved, an increase of 0.3% absolute compared to cells with conventional screen-printed contacts. This is mainly due to the reduction in the finger resistance to values as low as 14 Omega/m, which reduces the series resistance of the solar cell significantly. To retrieve the lumped series resistance as accurately as possible under the operating condition, different determination methods have been analyzed. Methods under consideration were fitting of the two-diode equation function to a dark IV-curve, integration of the area A under an IV-curve, comparison of a j(sc)-V-oc with a one-sun IV-curve, comparison of the jsc and V-oc points of a shaded curve with the one-sun IV-curve as well as comparison of a dark IV-curve with a one-sun IV-curve, and comparison of IV-curves measured at different light intensities. The performed investigations have shown that the latter four methods all resulted in reliable series resistance values

We present a standard p + pn + solar cell device exhibiting a full-area aluminum back surface field (BSF) and a conversion efficiency of 20.1%. The front side features a shallow emitter which has been exposed to a short oxidation step and reduces the emitter dark saturation current density j 0e to 160 fA/cm 2 on a textured surface. The front contact is formed by light-induced nickel and silver plating. Also, devices featuring screen-printed front contacts have been realized that reach a conversion efficiency of 19.8%. PC1D simulations are presented in order to extract the electronic parameters of the BSF. Therefore, external quantum efficiency and reflectance have been determined for modeling the internal quantum efficiency by adapting surface recombination and lifetime of the PC1D-simulated silicon device. As a result, a recombination velocity of S BSF = 283 cm/s and a dark saturation current density of j BSF = 274 fA/cm 2 in the Al BSF are determined. This results in an effective diffusion length L eff = 1150 μm.

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