A device for mass storage of information, the device comprising: a substrate (30); an electrically-conductive tip (10) for atomic force microscopy located above the surface (31) of said substrate (30) in electrical contact therewith; and a voltage generator (41) for applying a potential difference between said tip (10) and said substrate (30); the device being characterized in that: said substrate (30) has a surface (31) of a material presenting electrical conductivity that is both electronic and ionic in nature; and in that said generator (41) is adapted to apply a potential difference that is sufficient to induce a redox reaction of said material that modifies the surface electrical conductivity of the substrate (30). The use of such a device (1) for mass storage of information.