Nano-X-ray diffraction study of single Co-implanted ZnO nanowires

This work reports on the long-range order of single as-implanted and annealed ZnO:Co nanowires studied using a hard X-ray nanoprobe. For all nanowires, nano-X-ray fluorescence maps reveal a homogeneous distribution of Co ions implanted along the nanowires. For the as-implanted nanowires, however, nano-X-ray diffraction data shows a larger deviation from the bulk ZnO lattice along the c-axis induced by the ion implantation process. For the thermally annealed nanowires, on the other hand, the c lattice parameter is similar to the one of bulk wurtzite ZnO. The structural analysis of individual nanowires highlights the importance of the subsequent thermal annealing and emphasizes the critical role of the unavoidable damage created by the ion-implantation process. Such defects ultimately limit the use of semiconductor nanowires.