Effect of Sn Addition on Epitaxial GaAs Nanowire Grown at Different Temperatures in Metal-Organic Chemical Vapor Deposition

In this study, we investigated the growth behaviors of GaAs nanowires with tetraethyl-tin (Sn) as addition grown at different temperatures in a metal-organic chemical vapor deposition system. It was found that the nanowire axial growth rate can be influenced by the addition of Sn in opposite ways at different growth temperatures. The growth rate of nanowires is higher because of the enhanced decomposition of trimethyl gallium (TMGa) with increasing the Sn addition at 390 °C while lower because of the lower catalyst supersaturation level with increasing the Sn addition at 450 °C. With the Sn addition, nanowire quality can be maintained at 390 °C because the lower temperature benefits stabilizing the structure but further degraded at 450 °C when compared with intrinsic nanowires. This study provides an insight into the effect of the Sn addition on GaAs nanowire growth, which will be useful for the design of nanowire-based devices.