Crystal structures of GaAs/GaNAs core- multishell nanowire

摘要

Introduction of several % of N into GaAs can provide large variability in lattice constant and band gap. The introduction of heterostructure into the nanowire provides intentional carrier control within the ststem, showing the possibility for the realization of advanced electronic devices. In this study, we report the results of X - ray diffraction (XRD) and electron back scattered diffraction (EBSD) investigation on the structural properties of GaAs - based core - multishell nanowires with GaNAs shell layer prepared by molecular beam epitaxy. The introduction of N into the GaNAs shell showed the peak shift of zinc-blende (ZB) related XRD GaAs (111) peak to the high angle side, indicating the strain deformation of the entire nanowire. In addition, the N introduction reduces the intensity of the wurtzite(WZ)-related GaAs (0002) peak. The phenomenon was further investigated by EBSD. As a result, the WZ structures have smaller diameter than ZB phases, suggesting the transformation of WZ structure to ZB by the introduction of GaNAs shell