Optoelectronic Properties Of Gaas Nanowire PN Junction Used For Micro-System Applications

The research work is mainly supported by the grants from National Basic Research Program of China (Grant No.2010CB327600), the Major International (Regional) Joint Research Program of China (Grant No.6102010600), the National Natural Science Foundation of China (Grant No.61077049), the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No.20120005110011) and the Programme of Introducing Talents of Discipline to Universities (111Program) of China (Grant No.B07005).Nanowires have great potential in the new generation of nanoscale devices and systems. Having a direct band gap, III-V nanowires can obtain a high photoelectric conversion efficiency, which have a unique advantage in optoelectronic devices, such as photoelectric detectors and solar cells. Nanowire p-n junction is the core unit of a nanowire optoelectronic device. The research of electrical, optical and optoelectronic properties of p-n junction is important for the design and fabrication of high performance optoelectronic devices. This paper focuses on optoelectronic properties of GaAs axial and core-shell nanowires. Results are as follows:1. In this paper, the electrical properties of GaAs axial and core-shell nanowires are simulated by using the finite volume method (FVM). The effects of doping concentration, height and radius are studied. It is proved that GaAs core-shell nanowires have some benefits over axial nanowires.2. In this paper, the optoelectronic properties of GaAs axial and core-shell nanowires are simulated by using the finite difference time domain (FDTD) method. The effects of temperature, optical power and wavelength are studied. Conversion efficiencies of GaAs axial and core-shell nanowires are calculated in AM1.5G. The conversion efficiency of GaAs core-shell nanowire is calculated to be18.3%, which is much higher than that of the GaAs axial cell.3. Tungsten probe is made by anodic etching. The nanowires can be moved accurately by using the tungsten probe and the three-dimensional adjusting frame, preparing for the electrical and optical characteristics test of a single nanowire.