Effect of Indium Doping on the Growth and Physical Properties of Ultrathin Nanosheets of GaInN/ZnO Solid Solution

Abstract

We have prepared single-crystal, thin GaInN/ZnO solid-solution nanosheets by nitration of a single source Ga−In−Zn−O gel-like homogeneous precursor. The thickness of these nanosheets can be as low as about 2 nm. The In doping ratio typically was 1−2%. It is found that while indium plays an important role in the formation of the nanosheets and contributes to their narrow bandgap energy of about 2.55 eV, the impact of Zn doping on the bandgap shrinkage is higher than that of indium. An X-ray absorption near-edge structures (XANES) study confirms the validity of In doping in the solid solution, revealing that it increases chemical disorder, which is evident by the corresponding distortion of the Ga L3,2-edge and the N K-edge spectra. From the XANES, we observe that Zn atoms are displaced from the GaN lattice as In is incorporated into the solid solution. X-ray excited optical luminescence measurements show that indium doping reduces zinc acceptors in the GaN lattice, resulting in a blue shift and narrowing of the material’s emission band.