Characterization of CoxNiyO hybrid metal oxide nanoparticles as charge trapping nodes in nonvolatile memory devices

The CoxNiyO hybrid metal oxide nanoparticles (HMONs) embedded in the HfOxNy high-k dielectric as charge trapping nodes of the nonvolatile memory devices have been formed via the chemical vapor deposition using the Co/Ni acetate calcined and reduced in the Ar/NH3 ambient. A charge trap density of 8.96 × 1011 cm−2 and a flatband voltage shift of 500 mV were estimated by the appearance of the hysteresis in the capacitance-voltage (C-V) measurements during the ±5 V sweep. Scanning electron microscopy image displays that the CoxNiyO HMONs with a diameter of ∼10-20 nm and a surface density of ∼1 × 1010 cm−2 were obtained. The mechanism related to the writing characteristics are mainly resulted from the holes trapping. Compared with those devices with the CoxNiyO HMONs formed by the dip-coated technique, memory devices with the CoxNiyO HMONs fabricated by the drop-coated technique show improved surface properties between the CoxNiyO HMONs and the HfON as well as electrical characteristics.