A model for growth directional features in silicon nanowires

Long silicon nanowires (SiNWs) grown by laser ablation or by thermal evaporation of monoxide source materials are primarily oriented in the (112) direction, and some in the (110) direction, but rarely in the (100) or (111) directions. We propose a model to explain these SiNW growth directional features. The model consists of two parts. Part one is concerned with mechanism-based criteria and part two with applying these criteria to explain the experimental results. Four criteria are considered: (i) the stability of a Si atom occupying a surface site; (ii) the Si {111} surface stability in the presence of oxygen; (iii) the stepped Si {111} surface layer lateral growth process; and (iv) the effect of dislocations in providing perpetuating {111} steps to facilitate SiNW growth. Analyses of SiNW growth in accordance with these criteria showed that (112) and (110) are the preferred SiNW growth directions, and that (111) and (100) are not

Duke Scholars

Author Teh Yu Tan Thomas Lord Department of Mechanical Engineering and Materia ...