Demonstration of planar thick InP layers by selective MOVPE

We studied the selective metal-organic vapor-phase epitaxy of thick InP bulk layers. The work focused on the obtention of planar thick layers by an adjustment of the growth conditions. We showed that reduced pressure and temperature in the reactor allowed to decrease the sharpness of the thickness profiles in the vicinity of the mask. This approach is consistent with the vapor phase diffusion model and the kinetic theory. Thick InP layers generally show huge overgrowths at the edges of the dielectric stripes. These overgrowths were suppressed by reducing the growth rate. All samples’ thickness profiles were characterized by means of optical interferometer microscopy and surface profiler. Scanning electronic microscopy was used in the observation of the edge overgrowths and highlighted the complexity and anisotropy of the growth at these edges.