Gas-source molecular beam epitaxial growth and characterization of InNxP1-x on InP

We report a study of N incorporation into InP using a radio frequency (rf) N plasma source. Very streaky reflection high-energy electron diffraction patterns are observed for InNxP1-x(x<1%) grown on InP, indicating lager-by-layer growth of the film. The sharp x-ray diffraction peak and the clear Pendelloesung fringes in the high-resolution x-ray rocking curves reveal the high crystalline quality and uniformity of the film. They also suggest the smoothness of the interface between InP and InNxP1-x and of the surface of the InNxP1-x layer. This is further confirmed by scanning electron microscopy on these samples, where featureless surface is obtained. The formation of an InNP alloy is confirmed by x-ray theta . 2 theta diffraction measurement where no phase separation is observed. Different ways to increase the N composition in InNP were explored. At a fixed N-2 flow-rate fraction, lowering the growth temperature increases the N composition in InNP. Raising the rf power or using a larger beam exit aperture will also increase the N incorporation as a result of the availability of more active N species.