Self-assembled silicon nano-bridges as an enabler for nano-sensors

To build efficient sensors a large sensing area can be achieved by forming a massively parallel set of nanostructures. We have grown laterally oriented, metal-catalyzed silicon nanowires bridging between vertical (111) Si planes formed by anisotropically etching a [110]-oriented silicon wafer. The surrounding silicon can be developed into electrodes. The bridges are mechanically robust and resist significant force. By employing only coarse optical lithography to form the electrodes ("top-down" formation) combined with self-assembled ("bottom-up") fabrication of nanostructures, a large array of nano-scale sensors can be fabricated between biasing electrodes.