Cathodoluminescence Characterization of Dilute Nitride GaNSbAs Alloys Articles uri icon

publication date

  • September 2018

start page

  • 5061

end page

  • 5067

volume

  • 47

International Standard Serial Number (ISSN)

  • 0361-5235

Electronic International Standard Serial Number (EISSN)

  • 1543-186X

abstract

  • The effects of ex situ annealing in N ambient and in situ annealing in As ambient on GaNSbAs/GaAs structures grown by molecular beam epitaxy were investigated by low temperature cross-sectional cathodoluminescence (CL). The amount and distribution of Sb was measured by energy dispersive spectroscopy (EDS). The cross-sectional CL analysis of all samples reveals a shift of the near band edge (NBE) emission along the growth axis, presumably associated with a non-uniform incorporation of Sb during the growth process, in agreement with the Sb distribution measured by EDS in the as-grown sample. The NBE emission in the annealed samples presents a redshift with respect to the as-grown sample. This effect might be explained by a redistribution/activation of N in the GaNSbAs lattice since the Sb distribution measured by EDS does not reveal significant changes, within the error margin, with respect to the as-grown sample. The in situ annealed in the As overpressure sample shows the best properties for solar cells applications, i.e., a NBE peak position close to 1.0 eV and the lowest full width at half maximum of this emission.

keywords

  • dilute nitrides; gansbas; solar cells; cathodoluminescence; annealing