The fabrication of a novel class of microgrippers is\ud demonstrated by means of bulk microelectromechanical systems (MEMS) technology using silicon on insulator wafer substrates and deep reactive ion etching. Hard masking is implemented to maximize the selectivity of the bulk etching using sputtered aluminum and aluminum–titanium thin films. The microroughness problem related to the use of metal mask is addressed by testing different mask combinations and etching parameters. The O2 flow, SF6 pressure, wafer temperature, and bias power are examined, and the effect of each parameter on micromasking is assessed. Sidewall damage associated with the use of a metal mask is eliminated by interposing a dielectric layer between silicon substrate and metal mask. Dedicated combdrive anchors are implemented to etch safely both silicon sides down to the buried oxide, and to preserve the wafer integrity until the final wet release of the completed structures. A first set of complete devices is realized and tested under electrical actuation

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A new method for conductive via's using gold electroplating is presented. Tapered walls through wafer via (TWV) holes were made using a variable isotropy DRIE process, with a very good control over the obtained anglesangles of 11.3° and 21.8° were obtained with errors smaller than 10%. Barrier and seed layers were deposited in via's performed by PVD (Physical Vapor Deposition) techniques with a very good coverage of the walls. Finally, gold electroplating was used to fill the narrow part of via's.