Silicon integrated micro batteries based on deep reactive ion etching and through silicon via technologies

Abstract

A technology has been developed for the extreme miniaturization of lithium ion micro batteries using wafer level processing. These batteries will be used as electronic buffer storage in future miniaturized sensor nodes, data loggers, RFID devices and medical applications. Between 2000 and 10000 micro batteries can be fabricated on one 300 mm wafer being a low cost process. While standard silicon processing used in MEMS and 3D packaging can be used to define cavities for the electrochemical electrodes, current collectors and contacts, technology development was required to optimize the electrode pastes and electrolyte for application in the wafer processing. A novel battery design was tested with anode and cathode fabricated side by side in a planar arrangement which simplifies battery assembly significantly