Microcrystalline n-i-p solar cells deposited at 10 Å/s by VHF-GD

In the present paper, we report on thin-film microcrystalline silicon solar cells grown at high deposition rates on back-reflectors with optimised light-scattering capabilities. A single-junction solar cell with a conversion efficiency of η=7.8% (2 μm thickness) was fabricated at a deposition rate of 7.4 Å/s. Another microcrystalline cell was successfully implemented in a “micromorph” tandem (i.e. a microcrystalline/amorphous tandem cell with n–i–p–n–i–p configuration); the resulting initial conversion efficiency was η=11.2%. A 4 μm thick single-junction cell at a deposition rate of 10 Å/s and with a conversion efficiency of η=6.9% was fabricated on a non-optimised substrate. Special attention is drawn to near-infrared spectral response and interface optimisation.