Shape-Controlled Nanoarchitectures Using Nanowalls

A novel method for shaping and positioning ZnO nanoarchitectures using conventional lithography and catalyst-free metal organic vapor-phase epitaxy is demonstrated. Nanowalls and nanotubes of desired shapes and arrangements can be grown heteroepitaxially on Si substrates, and their electron-emission characteristics were optimized by changing their diameter and spacing. This method can be readily expanded to create many artificial 1 D and 2D structures, as required for various device applications.