Au induced crystallization and layer exchange in a-Si/Au thin film on glass below and above the eutectic temperature

• Published in: Journal of non-crystalline solids 2017-03, Vol.460, p.130-135
• Main Authors: Kishan Singh, Ch, Tah, T., Madapu, K.K., Saravanan, K., Ilango, S., Dash, S.
• Format: Article
• Language: English
• Subjects: Au induced layer exchange; Au-induced crystallization; Diffusion limited aggregation; Poly-Si
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2017.01.029

Au (metal) induced layer exchange and crystallization of amorphous Si (a-Si) on corning glass (CG) in a-Si/Au/CG thin film specimen upon vacuum annealing (~10−8mbar) is reported. The crystallization characteristics of these specimens at temperatures ranging on either side of the Au-Si eutectic temperature Te(Au-Si) are investigated. Our results shows that solid state diffusion assisted layer exchange of the a-Si and Au layer, followed by crystallization of a-Si into crystalline Si (c-Si) occur at 350°C (below the Te). The upper limit to this crystallization mechanism was observed to be above the Te(Au-Si) and this continues till ~400°C in the present study. Above this limit, the layer exchange phenomenon ceases and eutectic mixing reaction of Au-Si takes over to form diffusion limited crystalline aggregates of Si with different microstructural attributes. •Polycrystalline silicon on glass by Au induced crystallization•Layer exchange in a-Si/Au thin film bilayer•Effect of isochronal vacuum annealing on either side of the eutectic temperature Te(Au-Si)•Evolution of spatial regions with different microstructural features above the Te(Au-Si)