The Investigation Of Zinc Oxide Nanowires Material With Its Preparation And Properties

Zinc oxide (ZnO) is one kind of Ⅱ-Ⅵ direct wide forbidden gap semiconductor materialin composite of metal oxide (its energy gap is3.37eV), with large binding exciton energy(60meV) at room temperature. ZnO is one of the most abundant nano-structure materials inthe world. One dimensionality nanometer material with its novel physical and chemicalproperties is used in nano-devices for potential application in the nanotechnology research. ZnOis a kind of functional materials coupling semiconductor and piezoelectric properties. Thematerial has most abundant structure and properties with its rich structure and nature on themechanical, thermal, optical, electrical, optical electronics, piezoelectric electronics, conduction,sensing, biological medical and other different areas.The main work of this thesis is as follows:The first part: we use ultra tiny zinc oxide powder and carbon powder as reaction of rawmaterials. By chemical vapor deposition method, we grow six party system phase of ZnO singlecrystal nanowire on Si (001) substrate, which is along the [0001] crystal to the preferentialgrowth features and quasi perpendicular to the base.The second part: We change the reaction conditions, such as reaction temperature, reactionpressure, heating rate, cooling rate, not only get a large number of special structurenano-material, but also synthetise original of conical zinc oxide nanowires, and analysis theeffect on growth conditions in depth. By controlling the reaction pressure and repeating theexperiment, we obtain the controlled morphology in the conical ZnO nanowires, and furtherresearch the inner mechanism.The third part: Through a series of chemical processes, we isolate nano-material from the Sibase inanhydrous ethanol, and discrete into zinc oxide nanowires solution. We bond a piece of nanowire in two end points of high silver glue (99.99%). It makes up of single zinc oxidenano-devices with optical microscope, scanning electron microscope characterized it.The fourth part: We test I-V characteristic signal in the nano-scale devices, by firstmeasuring the fundamental Schottky barrier curve, in order to distinguish that device is good orbad. Then test the nano-device made by tapered nanowire, due to its asymmetry structural, bothends of the Schottky barrier height has great difference with different thickness. Themeasurement is in different bending conditions, due to the different of bending strain degree,lead to the different pressure potential on the device and change Schottky barrier height. Theoutput of the piezoelectric signals due to both ends of the barrier is caused by strain.