Nowadays, nano-science is being a popular topic, more and more people take part in the study of nano-structure. In this research project, we focus on the formation and preferred orientation of the nano-trenches induced by Au nano-particle catalyst on ZnSe layer. We have discovered an interesting phenomenon that annealing of Au droplets on a ZnSe surface can induce trenches along some certain directions. Base on the SEM, AFM and X-ray Laue diffraction studies, we found that the preferred migration directions of the catalyst droplet are among the <110> direction family. On a ZnSe(111) surface, each of the trenches is along one of the six <110> directions while on a ZnSe(100) surface, the trenches are along only two <110> directions anti-parallel to each other. Our preliminary understanding on these observations is also provided in this report. The results of this project open a brand new approach for the fabrication of ordered nanostructures of other materials.

Mr. Lau was a Year 1 Physics undergraduate students when he took part in our scheme. This scheme provided him an opportunity to carry out research based on the cutting-edge technologies and findings of our department.


Yuan Cai, Siu Keung Chan, Iam Keong Sou, Yu Fai Chan, Dang Sheng Su, and Ning Wang, “Temperature-Dependent Growth Direction of Ultrathin ZnSe Nanowires” Small, 3, No. 1, 111–115 (2007).

Y. Cai, S. K. Chan, I. K. Sou, Y. F. Chan, D. S. Su and N. Wang, "The size-dependent growth direction of ZnSe nanowires” Adv. Mater., 18, 109-114 (2006).