The characteristics of RuO2-SnO2 nanocrystalline-embedded amorphous electrode, grown by DC reactive sputtering, was investigated. X-ray diffraction (XRD), transmission electron microscopy (TEM), and transmission electron diffraction (TED) examination results showed that Sn and Ru metal cosputtered electrode in O-2/Ar ambient have RuO2-SnO2 nanocrystallines in an amorphous oxide matrix. It is shown that the cyclic voltammorgram (CV) result of the RuO2-SnO2 nanocrystalline-embedded amorphous film in 0.5 M H2SO4 liquid electrolyte is similar to a bulk-type supercapacitor behavior with a specific capacitance of 62.2 mF/cm(2) mum. This suggests that the RuO2-SnO2 nanocrystalline-embedded amorphous film can be employed in hybrid all-solid state energy storage devises as an electrode of supercapacitor. (C) 2004 Elsevier B.V. All rights reserved.