The effects of miscut toward (111)A of (001) GaAs substrates on a dislocation glide in compositionally step-graded (AI)GaInP buffers grown by metal-organic chemical vapor deposition have been investigated. The full width at half maximum of X-ray rocking curves and the tilt obtained from symmetric (004) reciprocal space mappings suggest that the average misfit glide length of alpha dislocations is longer in samples on 15 degrees off substrates than that on 7 degrees off substrates. Compared to the 7 degrees sample, the larger miscut 15 degrees more significantly weakens the blocking effect of the p dislocations on the motion of alpha dislocations, and it also provides a much stronger driving force on a dislocations in (111) slip planes, which greatly enhances the misfit dislocation glide. Eventually, the two effects collectively lead to a longer average misfit glide length of alpha dislocations and a lower threading dislocation density in the active layer on the 15 degrees off substrates, which is critical for improving the performances of devices based on lattice mismatched materials. (C) 2013 Elsevier B.V. All rights reserved.