The development of a robust method for integrating high-performance semiconductors on flexible plastics could enable exciting avenues in fundamental research and novel applications. One area of vital relevance is chemical and biological sensing, which if implemented on biocompatible substrates, could yield breakthroughs in implantable or wearable monitoring systems. Semiconducting nanowires (and nanotubes) are particularly sensitive chemical sensors because of their high surface-to-volume ratios. Here, we present a scalable and parallel process for transferring hundreds of pre-aligned silicon nanowires onto plastic to yield highly ordered films for low-power sensor chips. The nanowires are excellent field-effect transistors, and, as sensors, exhibit parts-per-billion sensitivity to NO2, a hazardous pollutant. We also use SiO2 surface chemistries to construct a nano-electronic nose library, which can distinguish acetone and hexane vapours via distributed responses. The excellent sensing performance coupled with bendable plastic could open up opportunities in portable, wearable or even implantable sensors.
Bibliographical noteFunding Information:
We thank W. Dichtel, A. Boukai and Y. Bunimovich for useful discussions. M.C.M. thanks the Intelligence Community Postdoctoral Research Fellowship Program for financial support. J.R.H. acknowledges primary support of this work via a contract from the MITRE Corporation, and support from the National Cancer Institute (#5U54 CA119347). Correspondence and requests for materials should be addressed to J.R.H.