Photoluminescence characteristic of co-doping zinc oxide film
Jhe Wei Liou1*, Yao Teng Chuang1, Wei Yen Woon1
1Condensed matter physics lab, Department of Physics, National Central University, Taoyuan, Taiwan
* presenting author:Jhe Wei Liou, email:roy810791@gmail.com
Zinc oxide is a wide direct band gap semiconductor with high exciton binding energy at room temperature which is a potential material for wide range of applications. Although many of the prospective applications for zinc oxide require both n- and p-type, high quality and stable p-type zinc oxide is still a challenge today.
Doping is well known process to control carrier type. However, in zinc oxide, the lower formation energy of donor defect states causes that single doping of V-group element with equilibrium way seems to be hard to realize high quality p-type. Thus, last few years, some theoretical research suggests that the combination of specific bonding and defects induces accepter level defects. It seems that co-doping may be a more possible way to realize p-type.
In our research, the high quality zinc oxide samples are prepared by chemical vapor deposition (CVD). With lower concentration initial donor defect, CVD is a better way for zinc oxide preparing. Ion implantation co-doping nitrogen and phosphorus ion and annealing in nitrogen and oxygen ambience are expected to enhance p-type. The crystal lattice reconstruction is detected by XRD. Hall and photoluminescence are introduced for detail electrical and optical properties measurement.
We found a better condition for zinc oxide growth and reconstruction in annealing process. It states that co-doping of nitrogen and phosphorus can actually enhance p-type. In oxygen annealing, zinc oxide p-type enhancing is much easier than nitrogen annealing.


Keywords: zinc oxide, Photoluminescence, co-doping, semiconductor, ion implantation