Nano-floating gate memories made of Al(2)O(3)/ZnO/Al(2)O(3) nanostructures were fabricated with chemically-driven ZnO nanocrystals embedded into high-k Al(2)O(3) thin films prepared through atomic layer deposition. The memory characteristics were analyzed through high-frequency capacitance-voltage measurement and current-voltage characteristics, along with high-resolution images of the aforementioned structures. The dotted ZnO nanocrystals function as charge-trapping/detrapping centers, inducing a very large memory window of 5.34 V. The defective nature of ZnO was optimally adjusted into the energy-band diagrams in combination with the tunneling and control layers of the robust Al(2)O(3) thin films. The measured memory characteristics exhibited superior retention features derived from the charge-trapping/detrapping behaviors. (C) 2011 Elsevier B.V. All rights reserved.