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Non-volatile memory based on TiN nanocrystal (TiN-NC) charge storage nodes embedded in SiO2 has been fabricated and its electrical properties have been measured.It was found that the density and size distribution of TiN-NCs can be controlled by annealing temperature. The formation of well separated crystalline TiN nano-dots with an average size of 5 nm is confirmed by transmission electron microscopy and x-ray diffraction, x-ray photoelectron spectroscopy confirms the existence of a transition layer of TiNxOy/SiON oxide between TiN-NC and SiO2, which reduces the barrier height of tunnel oxide and thereby enhances programming/erasing speed. The memory device shows a memory window of 2.5 V and an endurance cycle throughout 105.Its charging mechanism, which is interpreted from the analysis of programming speed (dVth/dt) and the gate leakage versus voltage characteristics (Ig vs Vg), has been explained by direct tunnelling for tunnel oxide and Fowler-Nordheim tunnelling for control oxide at programming voltages lower than 9V, and by Fowler-Nordheim tunnelling for both the oxides at programming voltages higher than 9V.