Nitric Acid Oxidized ZrO $_2$ as the Tunneling Oxide of Cobalt Silicide Nanocrystal Memory Devices

In this study, ZrO₂ formed by the nitric acid oxidation method is proposed to be the tunneling oxide for nonvolatile memory device applications. The sputtered Zr thin film was oxidized by immersing in the nitric acid solution (HNO₃:H₂O = 1:10) for 60 s at room temperature. The quality of the formed ZrO₂ was also extracted by the capacitance-voltage and current density-voltage measurements. Then, X-ray photoelectron spectroscopy has been used to confirm that the deposited Zr can be oxidized completely after the oxidation process. Moreover, a CoSi₂ thin film was deposited on the nitric acid oxidized ZrO₂ as the self-assembled layer of the memory device. After the device fabrication, the electrical and material characteristics of the CoSi₂ nanocrystal memory devices have also been demonstrated and discussed.