Thin-film polycrystalline silicon solar cells on ceramic substrates by aluminium-induced crystallization

Thin polycrystalline “seed layers” have been created on ceramic substrates using aluminium-induced crystallization (AIC) of amorphous silicon. An intermediate spin-on-oxide between substrate and AIC layer suppresses excessive nucleation and leads to larger grains. Epitaxial growth with high-temperature chemical vapor deposition has been successfully performed on these seed layers, yielding an average grain size around 5 μm. In this way, solar cells with grain size larger than active layer thickness have been made, reaching Voc values up to 460 mV and energy conversion efficiencies around 4.5%.