Metal induced growth of Poly-Si solar cells and sillicide nanowires by use of multiple catalyst layers

Polycrystalline Si thin films and single NiSi crystalline nanowires were made by the metal induced growth method. The different growth mechanisms for poly-Si and nanowires lie in the metal suicide formation. Poly-Si growth is based on metal disilicide formation and the growth of nanowires depends on metal monosilicide formation. The metal suicide formation depends on catalyst species and sputtering power. Following catalyst coating, Si was deposited in a DC magnetron sputtering system to grow poly-Si or nanowires. Several metals (Ni, Co, Co/Ni and Pd) were used as catalysts to confirm the nanowire growth mechanism as well as to fabricate solar cells. Poly-Si thin films were about 5 μm thick with up to 1 μm crystallite size. Nanowires were up to 10 μm long with about 50 nm diameter.