Significant Effects of Nitrogen Ion Implantation on Lithium Phosphorus Oxynitrid Solid State Electrolytes Via E-Beam Reactive Evaporation

Microbattery devices are strongly equipped with onboard power systems which consists of one important component, that is, solid-state electrolytes. The solid-state electrolyte thin films used in microbatteries could be perfect and free pinholes to aviod short circuites. In this study, lithium phosphorous oxynitride(Lipon) thin film has been fabricated successfully by E-beam reactive evaporated sintering Li₃PO₄ with the insertion of nitrogen ions. Scanning Electronic Microscopy(SEM) showed that  well-controlled film thickness and composition depend on the deposition parameter. Lipon thin films were examined by X-ray photoelectron spectroscopy (XPS), and the obtained results showed that the method of nitrogen ion implantation for the increase of nitrogen content in membrane is obvious and the decrease of the activation energy. Moreover, the lithium ion conductivity of the as-deposited Lipon thin films was investigated by impedance spectroscopy. It was found that the thin film exhibited high lithium ion conductivity. Due to three-coordinated nitrogen atoms, a higher cross-linked structure directly affects the ionic conductivity.