Fabrication of polycrystalline silicon thin films by gold-induced crystallization of amorphous silicon suboxide

• Published in: Vacuum 2021-10, Vol.192, p.110462, Article 110462
• Main Authors: Zamchiy, A.O., Baranov, E.A., Starinskiy, S.V., Lunev, N.A., Merkulova, I.E.
• Format: Article
• Language: English
• Subjects: Gold-induced crystallization; Phase transformation; Polycrystalline silicon; Silicon suboxide; Thin films
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2021.110462

In this work, polycrystalline silicon (poly-Si) thin films were synthesized using Au-induced crystallization of amorphous silicon suboxide for the first time. The structure and elemental composition of the substrate/Au/a-SiO0.4 stacked structure annealed at 500–700°C were investigated by transmission electron microscopy (TEM), Raman, and energy-dispersive X-ray spectroscopy (EDX). TEM and Raman methods confirmed the formation of a poly-Si thin film in the bottom layer (on the substrate) as a result of annealing. At the same time, TEM and EDX studies showed the formation of a thin (barrier) SiO2 layer with a thickness of ~5 nm located between the poly-Si thin film and the upper layer consisting of Au, Si, and O. Based on the results, a mechanism for the growth of poly-Si thin films is proposed which has features (dewetting of Au films and formation of a barrier SiO2 layer) that are not characteristic of the well-known layer exchange process. •Poly-Si thin films were synthesized using Au-induced crystallization of a-SiOx for the first time•Formation of a poly-Si thin film in the bottom layer (on the substrate) as a result of annealing•Formation of a thin (barrier) SiO2 5-nm-thick layer located between a poly-Si thin film and an upper layer•A mechanism for the growth of poly-Si thin films is proposed