Solution growth of polycrystalline silicon on quartz glass substrates

Polycrystalline silicon thin films were grown directly on quartz glass substrates from Cu-Si solutions with the addition of All at around 900degreesC. Al reduces SiO2 to Si and improves the affinity between the substrate and Si solution. From the 0.1 wt% Al added Cu-Si solution, the continuous polycrystalline Si layer with the thickness of about 10 mum was obtained on the SiO2 substrate. In contrast, for the substrate on which Al thin film was coated, only the discontinuous Si islands were observed. Our results indicate that Al addition to the solution is crucial to grow the continuous Si on the SiO2 substrates.