Nanocrystalline Silicon Thin Films Fabricated at 80 °C by Using Electron Cyclotron Resonance Chemical Vapor Deposition

Deposition of nanocrystalline silicon (nc Si) on glass at very low temperatures by electron cyclotron resonance (ECR) plasma enhanced chemical vapour deposition (PECVD) was investigated. It was shown that nc Si could be deposited from hydrogen diluted silane gas at a substrate temperature of 80 °C with a crystalline fraction up to 80% and a lateral grain size of around 50 nm. This was achieved by growing the nc Si in a low pressure regime which ensured that mono-silyl species were the dominant deposition precursor. Furthermore, a high flux of energetic hydrogen ions was required to induce crystallisation of the silicon material through a chemical annealing process.