Improvements in selective area growth of InP by metal-organic vapor phase epitaxy

Abstract

Improvements in selective area epitaxy (SAE) of InP have been achieved by optimizing the epitaxial parameters in metal-organic vapor-phase epitaxy (MOVPE). The significant effect of V/III ratio on the shape of the selectively grown ridge allows the tailoring of ridge geometries for device applications: at high V/III ratios, ridges with vertical side walls can be obtained on substrates with a slight appropriate misorientation. The data show that in contrast to metal-organic molecular-beam epitaxy (MOMBE) for SAE in MOVPE both surface kinetics (diffusion, adsorption-desorption relation) and gas phase diffusion play an important role; in MOMBE only surface kinetics is present and is almost comparable to the mechanisms found in the present study. The results are described by a qualitative model taking into account the dependence of the surface mobility of the adatoms on group V adsorption flux. The reduction of the adatom surface diffusion length should have significant consequences for selective growth of ternary and quaternary layers. These results will also impact selective area growth in the vicinity of mesa stripes, which is important for the monolithic integration of a laser ridge and a waveguide. >