Preparation and thermoelectric properties of nc-Si:(Al2O3 + SiO2) composite film

A composite film of nanocrystalline Si (nc-Si) embedded in (Al2O3 + SiO2) has been prepared on a quartz substrate by thermally evaporating a 400 nm thick Al film on a quartz substrate and annealing in air at 580 °C for 1 h. During annealing, the Al reacts with the SiO2 of the quartz substrate and produces nc-Si, which is embedded in the (Al2O3 + SiO2) film. The average size of nc-Si is ~ 22 nm and the thickness of the nc-Si:(Al2O3 + SiO2) composite film is ~ 810 nm. It is found that the prepared film is thermoelectric with a Seebeck coefficient of − 624 μV/K at 293 K and − 225 μV/K at 413 K.