수열합성법으로 플렉서블 기판에 성장된 Al doped ZnO(AZO) nanorods의 성장 조건에 따른 특성 연구

Abstract

Flexible transparent electrodes are essential components for flexible electronic devices, such as touch panels, organic light-emitting diodes, and solar cells. Indium tin oxide (ITO) is widely used as transparent electrode in optoelectronic devices. However, ITO has certain problems, mainly centered on its scarcity of supply, and its ceramic nature. Therefore, alternative transparent electrodes with excellent optical, electrical performance and mechanical flexibility will be greatly demanded.

Flexible electronic devices should be made under comparatively low temperature condition because of plastic’s low melting point. So it is difficult to obtain good properties.

Recently ZnO, possible to process in low temperature condition and have fast electron mobility, is received attention for material used in the flexible electronic devices. ZnO, representative II-VI oxide semiconductor, is chemically stable material having high exciton energy and comparatively wide band gap energy.

The substitution of Zn2+ ions with group III ions (B3+,Al3+,Ga3+,and In3+) generates extra electrons and improves ZnO optical, electrical, thermal, and magnetic properties. And Al3+ has been the most used dopant element due to its small ionic radius and low material cost.

Therefore, in this study, In the chapter 1, introduction about this study was briefly described. The chapter 2 introduce theoretical background of nanotechnology, characterization of nanostructure, 1-D ZnO, AZO and growth process by hydrothermal method.

The chapter 3 explains the effects of buffer layer on the growth of ZnO nanorods. The structure, electrical and optical properties of AZO nanorods were investigated by X-ray spectroscopy, field emission scanning electron microscopy and Hall effect measurement system.

And growth of AZO nanorods with several kinds of conditions, such as doping time and concentration, were explained at hydrothermal method. Finally, in chapter 5, results were summarized and concluded.