Abstract We report on the characteristics of rapid-thermal-annealed LiNi1yxCoxO2 cathode films for all-solid-state thin film microbatteries (TFBs). Scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy and Auger electron spectroscopy results show that the surface oxide layer formed on the as-deposited LiNi1yxCoxO2 film is completely removed by a rapid thermal annealing process. All-solid-state TFBs consisting of LiyLiPONyLiNi1yxCoxO2yPtyMgOySi exhibit stable cyclibility and a high specific discharge capacity of 60.2 uAh/cm2 um. It is concluded that the Li Ni Co O cathode could represent a promising candidate for a cathode film in TFBs.