Description: In this STTR program, Structured Materials Industries (SMI) and partners propose to develop an electrically contacted zinc magnesium oxide (ZnMgO) nanowire array for highly efficient UV focal plane arrays. The properties of ZnMgO make it a very promising material for optoelectronic devices. In particular, the wide bandgap (3.37 eV) and large exciton binding energy (60 meV), and the ability to fabricate stable, uniform ZnMgO nanowires make the material attractive as a sensor material.

Benefits: A ZnMgO nanowire focal plane array has great potential as a highly sensitive, low noise imager capable of operation over a broad wavelength range in the UV. The wide bandgap of ZnMgO will produce very little thermal noise. A dense array of nanowire will produce a very large absorption cross section for the design wavelength range. The precise control of the nanowire deposition process, including composition and diameter provides the ability to precisely tune the structures for particular wavelength ranges and objectives. Further, sensitizers (molecular or nanoparticle) on the surface of the nanowires may be used to further tune the optoelectronic response. All these factors lead to a high performance, UV imager.

The technology to produce large arrays of electrically contacted, highly uniform nanowires also has other applications. One application of great interest is t chemical sensing. By bonding specific receptors to the ZnMgO nanowires, highly sensitive and highly specialized chemical sensors may be fabricated. This technology may be used for gas and chemical sensors for industry as well as for military and homeland security applications.