Fabrication Of Patterned ZnO Nanorod Arrays And Transfer To Different Substrates

Vertically aligned ZnO nanorod (NR) arrays have been receiving increased attention because of theirunique photonic properties and potential applications in photonic devices. Vertically aligned ZnO nanorodarrays are being considered as important building blocks for various applications, each of these applicationshas different requirements in terms of nanostructure geometry, spacing, and alignment. The ability to buildnanocrystals with desired positions and shapes is essential not only to diversify their potential applicationsin electronics and optoelectronics but also to enhance their performance. Patterned growth of aligned ZnONRs have been achieved by using various patterning methods such as electron beam lithography (EBL),nanoimprint lithography (NIL), nanosphere lithography (NSL) and Laser-interference lithography (LIL).Among these, EBL is a promising method, which can fabricate various patterned structures with highprecision ratio in nanometer-scales. Transfer ZnO nanorod arrays with highly uniform and verticallyaligned to conductive substrates can effectively avoid the ZnO seed layer’s effect on the performance ofarray, at the same time we can make use of high crystalline ZnO nanorod array which is difficult to growon conductive substrate to construction of electronics and optoelectronics devices, thus to enhance theirperformance. Transfer ZnO nanorod arrays is prerequisite to produce high performance ZnO basednanodevices. In this thesis we carried out research mainly from the following three aspects.1. We controlled fabricated of ZnO nanorod arrays on Si, ITO and sapphire substrate and investigatedthe influence of the seed layers and substrates on the hydrothermal growth of ZnO nanorod arrays. Flowerlike ZnO nanorod arrays were fabricated on si and ITO substrate, we found that vertically aligned singleZnO nanorods could grown on the sapphire (0001) substrate. But their nanorods were thick in diameter,which could greatly limited their applications.2. The influences of the reaction time, reaction temperature and the precursor concentration on themorphology of the ZnO nanorod arrays, such as diameter, length and geometry, were investigated to reducethe diameter of nanorods. ZnO nanorod arrays with small diameter and high aspect ratio were successfullyfabricated by contrlolled the above reaction conditions. We have demonstrated an effective approach forfabrication ZnO nanorod arrays based nanodevices. 3. We report a nanoimprint assisted transfer method that enables the fabrication of vertically alignedZnO nanowires electronic devices on arbitrary substrates such as ITO glass slides, plastic sheets and copperfoil. Vertical ZnO nanorod arrays were successfully transfered to conducting substrate with their originVertical direction and integrity. We have demonstrated that vertical aligned ZnO nanorod arrays withdifferent density and periodic were successfully transfered to arbitrary substrate, such as ITO glass slides,plastic sheets and copper foils. The current-voltage characteristics of the devices were investigate with thevertical ZnO nanowire array on conductive substrate.