Effects of Zn doping on GaAs nanowires

Knowledge on doping effects is essential for fabrication of nanowire devices. While high doping levels may be required, nanowire growth can fail when doping is increased exceedingly. We report effects of Zn doping on different properties of GaAs nanowires, such as morphology, optical properties and growth rate. Nanowires with lower doping showed better and more consistent morphology while highly doped nanowires suffered from frequent crystal defects and a kinked structure. Additionally, doping increased the growth rate. Optical properties were surprisingly enhanced, which was seen as significantly higher photoluminescence intensity when compared to undoped nanowires. Zn impurities also redshifted the photoluminescence signal compared to the bulk band gap value.