The Synthesis Of Low Dimension GaN Nano Material By Sol-Gel

Gallium Nitride (GaN), as the representation of the third semiconductor material, is an important direct wide bandgap semiconductor material and is also one of the most advanced semiconductors in the world due to its excellcnt physical and chemical properties. It can be not only applied to light emitting devices, such as blue, near ultraviolet, violet light emitting diodes, laser and high temperature/high power microelectronic, but also empolyed as a new eco-friendly material applying into the environmental protection. Because of the outstanding characteristics, an amounts of research have been done with respect to GaN material and devices. The nano-sized materials, according to the requirement of decrease in the size of the device, are of great significance nanodevices because of their excellent natures.This research contains two parts:One is experiment part and the other is theoretical calculation.The first part:a novel two-step method of synthesizing GaN nano crystal is chiefly discussed, by means of a two-step combination of sol-gel proccss with high temperature ammoniating. At the same time, we discuss influence on the structure, elemental composition and the morphology of GaN nano crystal by ammoniated temperature and ammoniated time and therefore determine the best preparation condition. Ga2O3 gel and ammonia are used as the gallium source and nitrogen source respectively that the GaN nanowires are synthesized by high temperature ammoniating successfully. It reveals that ammoniated temperature and ammoniated time have a great influence on the crystal quality and the surface morphology of the GaN nanostructures. In addition, the effects of the process parameters on the properties of GaN nanostructures are discussed. Our research analyse the morphology, structure, elemental composition and photoluminescence characteristic of GaN nanostructure prepared under the best technological conditions and explore the growth mechanism for GaN nanostructures. The technique is suitable for the scale production because of lower price, easy to operate and efficency.The second part:Some physical properties of the cluster, such as energy structures, optical properties, magnetic properties and thermodynamic properties present transformation tendency from atomic property to bulk material property. Therefore, it is necessary to calculate the structure and property of the clusters theoretically. The B3LYP method of density functional theory (Density Functional Theory, DFT) is used to optimize geometry configuration of GanN3 (n=1-8) clusters at the level of 6-31G*. The bond properties, photoelectron energy spectroscopy and stability are calculated and analyzed, and the most stable structures are obtained finally which can explanation the formation of nano-materiais.