Formation of V-defects in InxGa1–xN/GaN multiple quantum wells, grown on GaN layers with different threading dislocation densities, was investigated. From cross-sectional transmission electron microscopy, it was found that not all of the V defects were always connected with threading dislocations at their bottom. By increasing the In composition in the InxGa1–xN well layer or decreasing the threading dislocation density of the thick GaN layer, many V defects were generated from the stacking mismatch boundaries induced by stacking faults which were formed within the multiple quantum well due to the strain relaxation. Also, threading dislocation density in the thick GaN layer affects not only the origin of V-defect formation but also the critical In composition of the InxGa1–xN well on the formation of V defects.

Formation Mechanism of V Defects in the InGaN/GaN Multiple Quantum Wells Grown on GaN Layers with Low Threading Dislocation Density. H.K.Cho, J.Y.Lee, G.M.Yang, C.S.Kim: Applied Physics Letters, 2001, 79[2], 215-7