Through-silicon vias using bosch DRIE process technology

Abstract

Silicon deep reactive ion etching (DRIE) is having a great effect on micro-electro-mechanical systems technology (MEMS) and quite recently also on memory devices and through-silicon via (TSV) etch applications. Nowadays, it is an established fabrication process within the MEMS field. The basic technology was originally developed at Bosch in the early 1990s. At that time, classical wet etching in KOH was the state-of-the-art technology, with design options like the silicon vias and also many others remaining unthinkable. With the Bosch DRIE process it became possible to overcome the design restrictions and compatibility problems related to the old silicon wet etching technology. The etching performance of the Bosch process is not reached by any wet etchant or other microstructuring technology. Today, after more than a decade of Bosch process plasma etching technology shaping the MEMS field, it is emerging also as a new enabler in other areas, e.g., for extremely precise high aspect ratio TSVs for stacking memory chips and other purposes. The Bosch process has evolved throughout the years thanks to continuing progress in process and hardware development. Today a broad supplier base is supporting DRIE customer needs in many application areas, with the industry's high-density plasma equipment and process know-how all over the world. © 2011 Springer Science+Business Media, LLC.