Effects of Substrate Miscut on the Quality of In0.3Ga0.7As Layers Grown on Metamorphic (Al)GaInP Buffers by Metal–Organic Chemical Vapor Deposition

In0.3Ga0.7As layers were grown by metal–organic chemical vapor deposition utilizing compositionally step-graded (Al)GaInP buffers on different misorientated GaAs substrates. The substrate miscut toward the [110] direction promotes α dislocation glide along the [110] direction while it exerts an adverse effect on β dislocations in the perpendicular direction with increasing the miscut degree. In comparison with the 2° and 7° samples, a better surface morphology with a RMS roughness of 5.77 nm and a lower density of threading dislocations indicated by the photoluminescence and transmission electron microscopy results were obtained in the 15° sample.