Self Consistent Model For InP Selective Regrowth by Hydride Vapour Phase Epitaxy

Abstract

The surface diffusion mechanism of InP selective regrowth around [110] and [110] directional etched InP mesas by hydride vapour phase epitaxy (HVPE) is investigated. A model has been proposed on the basis that the excess area growth in the immediate vicinity of mesas takes place due to an accumulation of materials fed by surface diffusion from the top of the mesa. The surface diffusion length and surface diffusion coefficient along [110] direction (i.e. case of [110] directional mesa) and [110] direction (i.e. case of [110] directional mesa) are estimated for the first time. It is observed that the surface diffusion length and surface diffusion coefficient towards [110] direction are about three and eight times higher than those towards [110] direction, respectively. The anisotropic growth behaviour in these directions is explained due to these differences in the surface diffusion lengths. The validity of the model is justified by a self consistent calculation.