Influence of Mn-doping on densities of screw- and edge-type threading dislocations in Ga1−xMnxN grown by metal organic chemical vapor deposition

A detailed study is presented on the influence of Mn-doping on densities of screw (c-type) and edge (a-type) threading dislocations (TDs) in Ga1−xMnxN grown by metal organic chemical vapor deposition (MOCVD) by using high-resolution X-ray diffraction (XRD). Three regions were present in Mn source rate dependence plots of density of c-TDs, and the mean twist angle corresponding to the density of a-TDs. In each region, Mn-doping exhibits different effects on the densities of a- and c-TDs, which is attributed to different dependences of the two types of TD on stresses. The results obtained from X-ray diffraction are consistent with those of atomic force microscope (AFM) measurements. It is further suggested that similar phenomena would occur when doping other elements into GaN grown by MOCVD.