2017/02/02 by L. Janicki, G. Kunert, M. Sawicki +5 · 29 citations
Materials Science · Physics and Astronomy · #Band gap #Electrical resistivity and conductivity #Fermi Gamma-ray Space Telescope #Fermi level #Ga2O3 and related materials #GaN-based semiconductor devices and materials #Impurity #Molecular beam epitaxy #Oscillation (cell signaling) #Quasi Fermi level #Semimetal #ZnO doping and properties #cond-mat.mtrl-sci
paper · pdf · doi:10.1038/srep41877
published in Scientific Reports 7(1), 41877 (Nature Portfolio) · 27 pages, 7 figures
openalex publication_date 2017/02/02 · openalex created_date 2017/02/10 · arxiv created 2017/12/16 · arxiv updated 2017/12/19 · openalex updated_date 2026/08/05
Abstract The Fermi level position in (Ga,Mn)N has been determined from the period-analysis of GaN-related Franz-Keldysh oscillation obtained by contactless electroreflectance in a series of carefully prepared by molecular beam epitaxy GaN/Ga 1−x Mn x N/GaN(template) bilayers of various Mn concentration x . It is shown that the Fermi level in (Ga,Mn)N is strongly pinned in the middle of the band gap and the thickness of the depletion layer is negligibly small. For x > 0.1% the Fermi level is located about 1.25–1.55 eV above the valence band, that is very close to, but visibly below the Mn-related Mn 2+ /Mn 3+ impurity band. The accumulated data allows us to estimate the Mn-related band offsets at the (Ga,Mn)N/GaN interface. It is found that most of the band gap change in (Ga,Mn)N takes place in the valence band on the absolute scale and amounts to −0.028 ± 0.008 eV/% Mn. The strong Fermi level pinning in the middle of the band gap, no carrier conductivity within the Mn-related impurity band, and a good homogeneity enable a novel functionality of (Ga,Mn)N as a semi-insulating buffer layers for applications in GaN-based heterostuctures.