A 2D layer of spherical, crystalline Ge nanodots embedded in a SiO2 layer was formed by low pressure chemical vapour deposition combined with furnace oxidation and rapid thermal annealing. The samples were characterized structurally by using transmission electron microscopy and Rutherford back scattering spectrometry, as well as electrically by measuring C-V and I-V characteristics. It was found that formation of a high density Ge dots took place due to oxidation induced Ge segregation. The dots were situated in the SiO2 at the average distance 5–6 nm from the substrate. Strong evidence of charge storage effect in the crystalline Ge-nanodot layer was demonstrated by the hysteresis behavior of the high-frequency C-V curves.
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