American Institute of Physics, Journal of Applied Physics, 2(110), p. 024310
DOI: 10.1063/1.3610396
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Quantum confined Ge nanocrystals embedded in high bandgap and high-k Al(2)O(3) dielectric matrix have been synthesized to demonstrate dual functional devices using Si-compatible fabrication technology. Transmission electron microscopy has shown the formation of Ge nanocrystals of varying diameter from 2.5 to 7.5 nm, much lower than the excitonic Bohr radius of Ge. A broad visible electroluminescence band at room temperature has been observed, which is attributed to the recombination of injected electrons and holes in Ge nanocrystals. An anti-clockwise hysteresis in the capacitance-voltage measurement of these devices indicates the charge storage in nanocrystals, useful for floating gate memory devices.