All solid-state rechargeable thin-film microsupercapacitor fabricated with tungsten cosputtered ruthenium oxide electrodes

We investigate an all solid-state thin-film microsupercapacitor (TFSC) fabricated with tungsten cosputtered ruthenium oxide electrodes (W-RuO2) and LiPON electrolyte. It is shown that the room-temperature charge–discharge behavior of the TFSC is similar to that of a bulk-type supercapacitor. It is also shown that the W-RuO2-based TFSC exhibits a higher discharge specific capacitance and more stable cyclibility, compared with those of the RuO2-based TFSC. Based on the pseudocapacitance of the oxide electrodes, the cycling behavior of the TFSCs and tungsten cosputtering effect on the electrochemical properties of TFSCs are described.