The present article gives a summary of recent technological and scientific developments in the field of polycrystalline silicon (poly-Si) thin-film solar cells on foreign substrates. Cost-effective fabrication methods and cheap substrate materials make poly-Si thin-film solar cells promising candidates for photovoltaics.
With an appropriate light trapping concept crystalline silicon thin-film solar cells can principally reach single-junction efficiencies of more than 17% close to that of silicon wafer-based solar cells, as calculated by Brendel in 1999 .
Eventually, the combination of high-bandgap and low-bandgap thin-film solar cells (such as perovskite/perovskite) could combine high efficiency and low cost, spelling the death of crystalline silicon PV technology.
Liquid phase crystallization approaches for poly-Si thin-film solar cells have the highest potential to achieve large grains, high VOC values and therefore high solar cell efficiencies by fast and cost-effective fabrication processes.
The current poly-Si thin-film solar cell efficiency record is still held by an SPC device . However, due to the limited grain size accompanied by a moderate material quality (VOC <500 mV) and long-lasting expensive fabrication processes the SPC technology was not competitive enough to survive on the global market.
The ability to engineer efficient silicon solar cells using a-Si:H layers was demonstrated in the early 1990s 113, 114. Many research laboratories with expertise in thin-film silicon photovoltaics joined the effort in the past 15 years, following the decline of this technology for large-scale energy production.