| Summary: | 碩士 === 國立虎尾科技大學 === 機械與機電工程研究所 === 95 === In this thesis, the reduced bimetallic oxide nanocrystal (BONs) embedded in the hafnium oxynitride (HfON) high-k film have been developed by means of the low-temperature chemical-vapor-deposition (CVD) method. The bimetallic acetate solutions were prepared by dissolving the X-metal acetate (CH3COOH)2X and Y-metal acetate (CH3COOH)2Y (X, Y= Co or Mo, or Fe) into ethanol. By modulated the various weight percentage of the bimetallic acetate, the different acetates mixed solutions, the various thicknesses of the HfON blocking oxide, the various dip-coating times, the drop-coating and the HfON surface treatment, the high-quality BON can be achieved for the nonvolatile flash memory (NFM) devices applications.
Capacitance-voltage (C-V) measurements estimate that a charge trap states density of 1.1 x 1012 cm-2 and a flatband voltage shift of 700 mV were achieved during the C-V hysteresis sweep at �b5 V for memory devices with CoxMoyO BONs. Scanning electron microscopy image displays that the CoxMoyO BONs with a diameter of ~4-20 nm and a surface density of ~1 x 1011 cm-2 were obtained. The results also show that the electrical and surface characteristics of memory devices with CoxMoyO BONs are better than those of memory devices with FexCoyO or FexMoyO. The electrical and surface properties of nonvolatile memory devices with CoxMoyO BONs can be further improved by the drop techniques and the TiOx incorporated into HfON surface. The writing characteristics measurements illustrate that the memory effects of devices with CoxMoyO, FexCoyO, and FexMoyO as charge trapping layers are mainly due to the holes trapping.
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