Zinc oxide (ZnO) is a promising wide band gap semiconductor. It has a direct energy band gap, Eg of 3.3eV at room temperature. ZnO can be alloyed with CdO and MgO to form the ternaries CdxZn1-xO and MgxZn1-xO, extending the direct energy band from 2.8eV to 4.0eV. Through proper doping, it also can be made transparent and conductive, piezoelectric, or ferromagnetic. ZnO based single crystal nano...

Wide bandgap semiconductor ZnO, GaN and InN nanowires have displayed the ability to detect many types of gases and biological and chemical species of interest. In this review, we give some recent examples of using these nanowires for applications in pH sensing, glucose detection and hydrogen detection at ppm levels. The wide bandgap materials offer advantages in terms of se...

Nanoscale zinc oxide (ZnO) rods of diameters close to the Bohr-exciton radius ( approximately 2 nm) can be prepared from a simple acetate precursor, resulting in ligand-capped rods of ZnO, highly dispersible in nonpolar solvents. Zinc oxide, ZnO, is a wide band-gap semiconductor with applications in blue/ultraviolet (UV) optoelectronic devices and piezoelectric devices. We observe self-assembly...

Semiconductor GaN NWs are promising components in next generation nano- and optoelectronic systems. In addition to their direct band gap, they exhibit piezoelectricity, which renders them particularly attractive in energy harvesting applications for self-powered devices. Nanowires are often considered as one-dimensional nanostructures; however, the electromechanical coupling leads to a third ra...

We report the first piezoelectric potential gated hybrid field-effect transistors based on nanotubes and nanowires. The device consists of single-walled carbon nanotubes (SWNTs) on the bottom and crossed ZnO piezoelectric fine wire (PFW) on the top with an insulating layer between. Here, SWNTs serve as a carrier transport channel, and a single-crystal ZnO PFW acts as the power-free, contact-fre...

Unusually large spontaneous and piezoelectric fields in the III–V nitrides have led to the making of an entirely new class of two-dimensional electron gas. Fluctuation from a perfectly periodic binary structure in highly polar semiconductor alloys present the same physical situation as a random distribution of microscopic dipoles. The excess dipole distribution in the barrier layers is evaluate...

Using a metal-semiconductor-metal back-to-back Schottky contacted ZnO microwire device, we have demonstrated the piezoelectric effect on the output of a photocell. An externally applied strain produces a piezopotential in the microwire, which tunes the effective height of the Schottky barrier (SB) at the local contact, consequently changing the transport characteristics of the device. An equiva...

Strain-induced polarization charges in a piezoelectric semiconductor effectively modulate the band structure near the interface and charge carrier transport. Fundamental investigation of the piezotronic effect has attracted broad interest, and various sensing applications have been demonstrated. This brief review discusses the fundamentals of the piezotronic effect, followed by a review highlig...

The precision stage is an essential device for optic fiber assembly systems, micro machines and semiconductor equipments. A new piezoelectric inchworm type actuator is proposed to implement an actuator-integrated long-stroke linear stage. An in-and-quadrature phase (I/Q) heterodyne interferometer is developed as a feedback sensor of a servo system, and a synchronized counting method is proposed...

A high-performance flexible piezoelectric nanogenerator (PNG) is fabricated by a direct writing method, which acquires both patterned piezoelectric structure and aligned piezoelectric nanowires simultaneously. The voltage output of the as-prepared PNG is nearly 400% compared with that of the traditional spin-coated device due to the effective utilization of stress. This facile printing approach...