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During the past 20 years,advances in micro/nano science and technology are leading to various chip-scale micro and nano devices developed and applied to many applications.On chip energy and/or power source devices is also under investigation to catch up this trend[1].In this paper,we present an on-chip all-solid-states thin film lithium-ion micro-battery with SnOx films doped with Cu as negative electrode.Fig.1 shows the structure of negative electrode of the developed microbattery.The silicon substrate is oxidized first and then a 0.3μm layer of Au is evaporated on the substrate.After that,a layer of SnOx is deposited on the Au layer by using RF sputtering technology.During sputtering,several copper thin plates with different areas are placed into the cabinet of the sputtering machine as the source for Cu doping.The generated SnOx thin film is analyzed by XRD,showing in Fig.2.It can be seen that the phase of SnOx thin films tends from crystalline to amorphous with the increase of doped Cu.Also,SEM picture (Fig.3) shows that with increasing Cu the particles on the surface of SnOx thin film became smaller.The performance of Cu-doped SnOx thin film as the negative electrode are electrochemically tested and Fig.4 shows the discharge capacity curves of SnOx vs cycle numbers of 3 samples.It can be seen that with the increase of doped Cu the discharge capacity of SnOx films is greatly increased.Based on above,we designed and fabricated all-solid-states lithium-ion microbatteries on the silicon substrate.For all of microbatteries developed,LiPON thin film is sputtered as the electrolyte and LiCoO2 thin film is sputtered as the positive electrode.Fig.5 shows the structure designed for on-chip all-solid-states LiCoO2/LiPON/SnOx and LiCoO2/LiPON/CuySnOx thin film lithium-ion micro-batteries.The tested results are shown in Fig.8 that LiCoO2/LiPON/CuySnOx batteries have larger discharge capacity and better circulation property than LiCoO2/LiPON/SnOx batteries.Especially,it can be seen from Fig.8 that the capacity of one cell microbattery with doped SnOx as negative electrode is 10-13nAh,and capacity of one cell of microbattery with undoped SnOx as negative electrode is only 4-6nAh.Requirements of higher capacity for applications in microsensors and/or microsystems can be obtained through series or parallel connection in arrays of developed microbatteries.