Structured Materials Industries, Inc. (SMI) with its partner, Drexel University, propose to build upon our Phase I success and continue the development of electrically contacted zinc oxide nanowire (NW) arrays for highly efficient solar blind UV sensors, and implement them in a packaged prototype product. The properties of ZnO make it a very promising material for optoelectronic devices. In particular, the wide bandgap (3.37eV) and large exciton binding energy (60meV), and the ability to fabricate stable, uniform ZnO nanowires make the material attractive as a sensor material. A ZnO nanowire focal plane array has great potential as a highly sensitive, low noise imager capable of operation over a broad wavelength range. The wide bandgap of ZnO will produce very little thermal noise. A dense array of nanowires, properly designed, will produce a very large absorption cross section for the design wavelength range. The precise control of nanowire deposition, including composition and diameter provides the ability to adapt the structures for particular objectives. Further, sensitizers (molecular or nanoparticle) on the surface of the nanowires may be used to tune the optoelectronic response further. The unique material system allows fabrication processes compatible with silicon IC technology, providing high quality, low-cost devices.
Benefit: The primary market for this technology will be military, for remote monitoring and for detection of hostile actions. There are further markets available to the imager in industrial settings and elsewhere for solar blind imaging. Other uses include hydrogen and natural gas fire detection, electrical corona discharge detection, and monitoring some industrial manufacturing processes. The technology may also prove highly useful for chemical sensing with further development.
Keywords: Multi-spectral, ultraviolet, zinc oxide, Nanowire, Solar blind, ultraviolet detector, Imager, focal plane array