The defect structure of periodic Si δ-doped GaN films grown by low-pressure metal-organic chemical phase deposition was investigated by means of high-resolution X-ray diffraction. The rocking curves for 5 planes, (00▪2), (10▪3), (10▪2), (10▪1) and (20▪1), were investigated. A pseudo-Voigt function was used to simulate the rocking-curve of every plane. The effects of Si δ-doping upon the various types of dislocation were considered. It was demonstrated that Si δ-doping significantly reduced the numbers of threading dislocations with a purely edge character, and induced no changes in the threading dislocations having a screw component. The results were consistent with atomic force microscopy results.

Reduction of Threading Edge Dislocation Density in n-Type GaN by Si Delta-Doping. Y.B.Pan, Z.J.Yang, Z.T.Chen, Y.Lu, T.J.Yu, X.D.Hu, K.Xu, G.Y.Zhang: Journal of Crystal Growth, 2006, 286[2], 2006, 255-8