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Enormous manufacturing cost and technical complexity of continued shrinking of electronic devices through the conventional transformative "top-down" approach have motivated efforts worldwide to explore simpler alternatives. New nano-scale assembly technology, such as catalyzed or self-assembled growth of nanowires and quantum dots, may enormously benefit integrated circuit fabrication technique methods. In the recent past, semiconductor nanowire devices have exhibited many novel electronic, optical and chemical properties. Despite a significant progress in nanowire synthesis and many promising single device demonstrations, nanowire applications have been hindered by our incapability to incorporate them within ICs. Several research groups have demonstrated an approach of serially connecting metal electrodes to individual nanowires using costly and slow e-beam lithography and made considerable investigations of the nanowire devices. However, none of those are massively parallel and manufacturable interfacing techniques that are crucial for reproducible fabrication of dense, low-cost nanodevices. In this paper, we present a novel bridging techniques that can connect a large number of highly directional metal-catalyzed nanowire devices between two pre-fabricated electrodes. Two opposing vertical and electrically isolated semiconductor surfaces are fabricated using coarse optical lithography along with wet and dry etching. Lateral nanowires are then grown from one surface and epitaxially connected to the other, forming mechanically robust "nano-bridges". By forming the structure on a silicon-on-insulator (SOI) substrate, the needed electrical isolation is achieved. The bridges are found to be mechanically robust and can resist significant force and chemical attacks. The technique, for the first time, can help access individual nanowire devices without using a nanoprobe or expensive lithography techniques. Using this novel bridging technique, novel nano-electronic and photonic devices can be designed and integrated with conventional circuits. The results will open doors to unprecedented device-density in integrated circuits, eventually making the nanowire based devices a commercial reality.
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