Zinc blende and wurtzite crystal structure formation in gold catalyzed InGaAs nanowires

Abstract

III-V semiconductor nanowires made of materials which have the zinc blende crystal structure in bulk are well known to exhibit either the zinc blende or the wurtzite crystal structure. Understanding and controlling which crystal structure that forms is of highest importance for nanowire applications in a variety of areas. In addition to this, composition control in ternary nanowires is another key technology area for successful nanowire applications. We derive a general model, based on two-component nucleation theory, which we use to explain the so far less understood experimental observations of zinc blende, wurtzite, and mixed crystal structure as a function of growth conditions and composition, x, in gold catalyzed InxGa1-xAs nanowires. An interesting theoretical finding is that the wurtzite and zinc blende phases have different compositions, even if they are nucleated from the same catalyst particle at the same conditions.