Charge storage characteristics of Au nanocrystals embedded in high-k gate dielectrics on Si

The charge storage characteristics of metal-oxide-semiconductor structures containing Au nanocrystals in atomic-layer-deposited high-k gate dielectrics were studied. Cross-sectional high-resolution transmission electron microscopy reveals that the Au nanocrystals are self-assembled in the high-k dielectric matrix after high temperature annealing in N-2 ambient. The memory effect was observed from capacitance-voltage (C-V) relations and a satisfactory charge retention characteristic was obtained in the sample using Al2O3 as the gate dielectric than in the one using Hf2AlOx. Moreover, a saturation of electron storage in the metal-oxide-semiconductor capacitors was also observed. (c) 2007 American Institute of Physics.