I. Introduction
Single crystal lithium niobate (ln) has been widely used in surface acoustic wave (SAW) devices owing to its large piezoelectric coefficient. Low electric conductivity, which is on the order of [1]–[3], coupled with the intrinsic pyroelectricity of LN generates pyroelectric surface charges with temperature changes. The surface charging and associated sparking may damage electrodes and fracture crystals during device production processes [4]. The surface charging effect, on the other hand, causes contact electrification when LN is used as a contacting material [5].