A floating-gate capacitor memory device containing nanocrystalline MoOx embedded ZrHfO high-k gate dielectric has been fabricated and studied for the nonvolatile memory properties. The charge trapping capacity and trapping site were investigated with the capacitance-voltage measurements. The memory functions were mainly contributed by the hole-trapping mechanism. The leakage current-voltage curve was consistent with the above result and showed the coulomb blockade effect. From the extrapolation of the charge retention data, this device could retain more than 50% of trapped charges over 10 years. This is a potentially feasible dielectric structure for future nanosize nonvolatile memories. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.020206esl] All rights reserved.