Recent Advances in Three Dimensional Thin Film Microbatteries

Abstract

ABSTRACTAutonomous MEMS require similarly miniaturized power sources. We present the first three-dimensional (3D) working thin-film microbattery (MB) technology that is compatible with MEMS requirements. Our 3D MBs are formed in perforated substrates (silicon chip or glass microchannel plate), in which a sandwich-like thin-film battery structure is deposited conformally and sequentially on all available surfaces, using wet chemistry. The area of high aspect ratio holes in the substrate enhances the capacity and energy density per given substrate footprint by more than an order of magnitude. Full 3D cells were manufactured on both glass and silicon substrates. A 3D cell on a micro-channel plate substrate exhibited a capacity of ca. 2mAh/cm2, in good agreement with the ca. 23 times area gain provided vs an identical footprint 2D cell.