The size control of uniform nanocrystalline Si grains by constrained growth model

Size-controlled nanocrystalline silicon (nc-Si) has been prepared from a-SiNx/a-Siffl/a-SiNx ( 'a' standing for amorphous) sandwich structures by thermal annealing. Transmission electron microscope analyses show that the mean size and the grain size distribution (GSD) of the nc-Si are controlled by the annealing conditions and the a-Si sublayer thickness. Based on our theoretical model of constrained crystallization, we interpret the phenomena of the growth halt of nc-Si and higher crystallization temperature for the thinner a-Si sublayers. The experimental results show that constrained crystallization method is promising to achieve uniform and high density nc-Si array which can be used in the future nano-devices.