Fabrication and characterization of Bi2Se3 wall-like nanostructure
Yen-Cheng Lin1*, Hsin-Yen Lee1, Jen-Kai Wu1, Yu-Sung Chen1, Chao-Chun Lee1, Chi-Te Liang1, Yuan-Huei Chang1
1Department of Physics, National Taiwan University, Taipei, Taiwan
* presenting author:林彥成, email:ericajax1989@gmail.com
We report the growth and characterization of topological insulator material bismuth selenide (Bi2Se3) wall-like nano-structures. The nano-structures were grown by an unconventional chemical-vapor-deposition (CVD) method. In our method, the substrates were placed upside down on the inner top part of the quartz tube, and in the down stream of the bismuth and selenide powders. The carrier gas was Ar gas, the flow rate was 30 sccm and the powders were heated to a temperature of 400 °C. Morphology of the nano-structures were examined with scanning electron microscope (SEM) and it was found that the nano-structure exhibited primarily triangular shape with special wall-like structure. Atomic force microscope (AFM) measurement indicates the center thickness of wall structure was about 50 nm and the thickness of the wall was about 120 nm. X-Ray diffraction (XRD) measurements indicate that the samples were of good crystalline quality and the energy-dispersive X-ray spectroscopy (EDS) measurements confirm that the bismuth and selenide ratio of our samples was 2 to 3.

Keywords: Bi2Se3