The impact of ScO(x)N(y) interlayers on unintentional doping and threading dislocations in GaN
Zhu, T and Moram, M A and Rao, D V S and Li, H and Kappers, M J and Oliver, R A and Walther, T and Nellist, P D and Hutchison, J L and Cullis, A G
To reduce the threading dislocation density in (0001) GaN grown on c-plane sapphire, a series of samples have been grown using scandium oxynitride (ScOxNy) interlayers (ILs) on AlN-on-sapphire templates. Scanning capacitance microscopy (SCM) has been employed to investigate the unintentional doping in GaN with varying ScOxNy IL thicknesses. The use of ScOxNy ILs decreases the threading dislocation density. An unintentionally n-doped layer has been identified by SCM close to the GaN/ScOxNy interface. The average width of this conductive layer has been quantified and found to increase as the ScOxNy IL thickness increases up to 13 nm.
Department of Materials
Imperial College London
Royal School of Mines
London, SW7 2AZ - UK