Low-temperature epitaxial thickening of sub-micron poly-Si seeding layers on glass made by aluminium-induced crystallisation

The formation of device-grade polycrystalline silicon (poly-Si) films on standard glass at low temperature (i.e., below the softening point of the glass) using simple and fast processes is one of the major challenges for low-cost thin-film solar cells. In this paper, we report what is believed to be the first successful realisation of thick (/spl sim/5 /spl mu/m), large-grained (/spl sim/5 /spl mu/m), continuous poly-Si films on glass at T<650/spl deg/C. This technological breakthrough has been achieved by using ion-assisted deposition at 630/spl deg/C for epitaxially thickening a thin (/spl sim/0.4 /spl mu/m) seeding layer made on glass by aluminium-induced crystallisation.