Dislocation behaviours were analyzed in AlGaN/GaN multiple-quantum-well films grown with different strain-modified interlayers. In the case of multiple-quantum-well layers grown on a GaN buffer layer without the interlayer, many threading dislocations interacted and annihilated within about 100nm below the multiple quantum well layer. For multiple-quantum-well layers grown with the AlGaN interlayer, misfit dislocations between the GaN buffer layer and the AlGaN interlayer enter multiple-quantum-well layers and resulted in an increase of threading dislocation density. Besides misfit dislocations, the edge-type dislocation was another dislocation origin attributed to the dissociation of Shockley partials bounding the stacking fault in AlN/GaN superlattices below the interlayer interface

Dislocation Behavior in AlGaN/GaN Multiple Quantum-Well Films Grown with Different Interlayers. H.H.Sun, F.Y.Guo, D.Y.Li, W.Lu, D.G.Zhao, L.C.Zhao: Chinese Physics Letters, 2012, 29[9], 096101