Memory devices containing the nanocrystalline Si embedded Zr-doped HfO 2 high-k dielectric film, which have many advantages over the conventional non-doped high-k films, have been prepared and characterized. The memory effect was manifested by the large counterclockwise capacitance-voltage hysteresis, e.g., 2.98V, and negative differential resistance region in the positive bias current-voltage characteristics. A large memory operation window, e.g., 0.72 V, with a long charge retention time, e.g., > 10,000 s, was achieved under the proper gate stress voltages. It is a viable dielectric for future nano-size metal oxide semiconductor field effect transistors and capacitors. 2006 The Japan Society of Applied Physics.