The promise and perils of wide-bandgap semiconductor nanowires for sensing, electronic, and photonic applications

The importance of wide-bandgap semiconductor nanowires, such as GaN, ZnO, and InN for making sensors, electronics, and photonic devices, is discussed. The large surface area of the nanowires makes them suitable for gas and chemical sensing, and the ability to control their nucleation sites makes them appropriate for microlasers or memory arrays. ZnO forms a heterostructure system with MgO and CdO that can be in blue/UV optoelectronics, transparent electronics, spintronics devices, and sensor applications. It has a direct badngap energy of 3.37 eV, which makes it transparent in covers. Temperature dependence of the resistance of an InN nanowires enables them to be used in resistors and other electronic devices. The InN nanowires can also be used for detection of various gases since the reversible chemisorption of reactive gases at the surface of nitrides and oxides can produce a large and variation in the conductance of the material.