Study on Raman scattering spectroscopy of Mn-doped GaN grown by the ammonothermal method

Abstract

Mn-doped GaN crystals of a-plane and (11−22) plane were grown by the ammonothermal method. The Mn concentrations were characterized on the order of 10²⁰ cm⁻³ by glow discharge mass spectrometry, and the valence state of Mn in GaN crystals was measured to be a mixed valence state of Mn²⁺ and Mn³⁺ using X-ray photoelectron spectroscopy. Raman scattering spectroscopy shows that due to the doping of Mn, the interaction potential energy between Ga and N ions changes, and the longitudinal optical mode E₁(LO) shifts towards a lower frequency. The Raman scattering spectra of Mn–Mg_k cation complexes formed by unintentional doping of Mg on the (11−22) plane were studied.