The stored charge characteristics of Ni-silicide nanocrystals embedded in nitride formed by annealing a Ni-Si-N thin film were studied in this paper. We used X-ray photoelectron spectroscopy, leakage current density, and X-ray diffraction to offer chemical material analysis of nanocrystals with surrounding dielectric and the crystallization of nanocrystals for different thermal annealing treatments. Transmission electron microscope analyses revealed nanocrystals embedded in the nitride layer. Nonvolatile Ni-Si nanocrystal memories with 600 degrees C annealing revealed superior electrical characteristics for charge-storage capacity and reliability compared with the memories with 300 and 500 degrees C annealing. In addition, we used energy-band diagrams to explain the significance of surrounding dielectric for reliability. (C) 2008 The Electrochemical Society.