Growth and optical property characterizations of ZnTe:(Al,N) layers using two co-doping techniques

In order to get around the high and activated n-doping levels for ZnTe, the co-doping technique known as effective method to overcome the dopant compensation was explored. The co-doping concept is to introduce two oppositely polar atoms at the same time in a 2:1 ratio, forming metastable three-atom complexes located at adjacent crystal sites. In this study, two types of deposition process were considered to place the co-dopants at the intended site, and the co-doped ZnTe:(Al, N) layers were grown on (001) oriented ZnTe substrates by molecular beam epitaxy. From the low temperature PL spectra, the increase of Al activation was confirmed by using co-doping sequences, and the activation of N dopant was also confirmed for one doping sequence even thought the doping level was maintained the same.