Facet stability of GaN during tri-halide vapor phase epitaxy: an -based approach

An ab initio -based approach is used to investigate the facet stability of GaN during tri-halide vapor phase epitaxy (THVPE). First, surface reconstructions are analyzed to create surface phase diagrams as a function of the gaseous pressure and temperature. Next, a triangular wedge model is used to compute absolute surface formation energies with the bulk state as a reference. A Wulff construction is used to predict the crystal growth form composed of energetically preferred facets. The calculated results can be used to control the shape of GaN grown by THVPE. An ab initio -based approach is used to study the facet stability of GaN during THVPE. The surface phase diagrams as functions of temperature and pressure are determined. Wulff construction is used to predict the crystal shape.