  Recently, liquid-phase crystallization of thin silicon films has emerged as a
promising candidate for thin-film photovoltaics. On 10 \mu m thin absorbers,
wafer-equivalent morphologies and open-circuit voltages were reached, leading
to a record efficiency of 12.1%. However, short-circuit current densities are
still limited, mainly due to optical losses at the glass-silicon interface.
While nano-structures at this interface have been shown to efficiently reduce
reflection, up to now these textures caused an increase in recombination.
Therefore, optical gains were mitigated due to electronic losses. Here, the
SMooth Anti-Reflective Three-dimensional (SMART) texture is introduced in order
to overcome this trade-off. By smoothing nanoimprinted SiOx nano-pillar arrays
with spin-coated TiOx layers, light-trapping properties of laser-crystallized
silicon solar cells could significantly be improved as successfully shown in
three-dimensional simulations and in experiment. At the same time, the smooth
surface morphology of SMART textures allows preserving electronic material
quality equivalent to that of planar reference samples and reaching Voc values
above 640 mV in 8 \mu m thin liquid-phase crystallized silicon solar cells.
Furthermore, the short-circuit current density jsc could be increased from 21.0
mA cm-2 for planar reference cells with already optimized anti-reflective
interlayer stacks to 23.3 mA cm-2 on SMART textures, corresponding to a
relative increase of 11%.
