Testing the limits of silicon technology based MEMS materials

This paper summarizes some advances by the Microsystem Materials Laboratory of the Institute of Microsystem Technology IMTEK, University of Freiburg, in testing and transcending current limits of micro materials and MEMS structures. The emphasis is on materials inspired from silicon IC technology enhanced by micromachining. Three studies of the fracture of micromaterials and microstructure are reported dealing respectively with the shock resistance of epipoly, the failure of PEVCD silicon nitride membranes under particle impact, and the fracture of LPCVD silicon nitride membranes under differential pressure. Extensions of the application range of MEMS are illustrated using polysilicon thin films operated at temperatures up to 1200 K, microstructures for differential thermal analysis, and the use of sharp silicon microstructures for embossing and scratching materials with Vickers hardness from 4 HV to 73 HV. Finally, an analysis of higher-order offset components in integrated Hall sensors is presented.