An in-situ and ex-situ transmission electron microscopy study of the substrate orientational dependence of the solid-phase epitaxial growth of amorphized GaAs

In-situ transmission electron microscopy (TEM) has been utilised in conjunction with conventional ex-situ TEM to study the influence of substrate orientation on the solid-phase epitaxial growth (SPEG) of amorphized GaAs. A thin amorphous layer was produced by ion implantation of As and Ga ions into semi-insulating (100), (110) and (111) GaAs substrates. In-situ annealing at ~260°C in the electron microscope was performed to study the influence of substrate orientation on the SPEG of amorphized GaAs. Quantitative analysis has demonstrated that the non-planarity of the amorphous-crystalline (a/c)-interface was greatest for the (111) substrate orientation. Conversely the a/c-interface is planar for the (110) substrate. The angle of the microtwins with respect to the a/c-interface was measured and it has been shown that the angle in the case of (111) plane was largest. This is consistent with in-situ TEM results, and thus confirming that the a/c-interface for the (111) is the roughest