High-resolution microbeam x-ray diffractometry applied to InGaAsP/InP layers grown by narrow-stripe selective metal-organic vapor phase epitaxy

We measure the diffraction peaks of InGaAsP selective metal-organic vapor-p hase epitaxial layers on 1.7-mu m-wide InP stripe regions between a pair of SiO2 mask stripes. This is achieved by using an x-ray microbeam with low a ngular divergence and a narrow energy bandwidth that was produced through t wo-dimensional condensation of undulator radiation x rays from a synchrotro n light source using successive asymmetric diffraction. The lattice strain is investigated by changing the SiO2 mask width from 4 to 40 mu m. The rock ing curves reveal clear peak shifts in the InGaAsP layers from the higher a ngle side to the lower angle side of the InP substrate peaks as the mask wi dth increases. (C) 2000 American Institute of Physics. [S0003- 6951(00)0193 5-5].