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 eta = 7.8% (2 mum thickness) was fabricated at a deposition rate of 7.4 Angstrom /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 eta = 11.2%. A 4 mum thick single-junction cell at a deposition rate of 10 Angstrom /s and with a conversion efficiency of eta = 6.9% was fabricated on a non-optimised substrate. Special attention is drawn to near-infrared spectral response and interface optimisation. (C) 2001 Elsevier Science B.V. All rights reserved.