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Register a new userUltra-low dissipation patterned silicon nanowire arrays for scanning probe microscopy
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In recent years, self-assembled semiconductor nanowires have been successfully used as ultra-sensitive cantilevers in a number of unique scanning probe microscopy (SPM) settings. We describe the fabrication of ultra-low dissipation patterned silicon nanowire (SiNW) arrays optimized for scanning probe applications. Our fabrication process produces, with high yield, ultra-high aspect ratio vertical SiNWs that exhibit exceptional force sensitivity. The highest sensitivity SiNWs have thermomechanical-noise limited force sensitivity of $9.7pm0.4~text{aN}/sqrt{text{Hz}}$ at room temperature and $500pm20~text{zN}/sqrt{text{Hz}}$ at 4 K. To facilitate their use in SPM, the SiNWs are patterned within $7~mutext{m}$ from the edge of the substrate, allowing convenient optical access for displacement detection.
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