Electrochemical properties of LiPON films made from a mixed powder target of Li3PO4 and Li2O

Abstract Lithium phosphorus oxynitride (LiPON) films were prepared by radio frequency magnetron sputtering. In order to control the atomic composition of the films, a mixture of Li 3 PO 4 and Li 2 O powders was used as the sputtering target. The ionic conductivity of the films showed a maximum (6.4 × 10 − 6 S/cm) when the molar ratio of Li 3 PO 4 to Li 2 O in the target was 1:2. The films formed from a target not containing Li 2 O showed good durability in air at the expense of slightly poorer ionic conductivity. This is probably due to the amount of Li in the film being significantly less which effectively suppressed absorption of CO 2 in air.