A nanowire gauge factor extraction method for material comparison and in-line monitoring

We propose a new non-destructive extraction method of gauge factor (GF) of nanowires (NW) for in-line monitoring of this parameter and piezoresistive material properties comparisons. Unlike destructive conventional techniques which also suffer from reproducibility issues, this method allows a direct measurement of the GF locally at the nanoscale and at the wafer level. GFs have been reliably measured on a wide range of silicon-based NEMS resonators with different designs, crystalline structures and doping levels. For monocrystalline devices, the extracted values are in good agreement with typical values obtained for NWs fabricated with well-controlled top-down processes. These values are also compared with polysilicon (polySi) NEMS, which look promising for low cost solutions.