In-Doped Gallium Oxide Micro- and Nanostructures: Morphology, Structure, and Luminescence Properties

Abstract

The influence of indium doping on morphology, structural, and luminescence properties of gallium oxide microand nanostructures is reported. Indium-doped gallium oxide micro-and nanostructures have been grown by thermal oxidation of metallic gallium in the presence of indium oxide. The dominant morphologies are beltlike structures, which in many cases are twisted leading to springlike structures, showing that In diffusion in Ga 2 O 3 influences the microstructure shapes. High-resolution transmission electron microscopy has revealed the presence of twins in the belts, and energy-dispersive X-ray spectroscopy in the scanning electron microscopy (SEM) has detected a segregation of indium impurities at the edges of planar structures. These results suggest that indium plays a major role in the observed morphologies and support the assumption of a layer by layer model as growth mechanism. An additional assessment of indium influence on the defect structure has been performed by cathodoluminescence in the SEM, X-ray photoelectron microscopy, and spatially resolved Raman spectroscopy.

Structural and Luminescence Properties of Ga2O3:Zn Micro‐ and Nanostructures

“…Figure shows polarized, local µ‐Raman spectra from a representative individual ribbon. The observed peaks are the characteristic ones of Ga 2 O 3 , confirming that no other phases have been formed in doped samples. The peak at 520 cm −1 is due to the Si substrate.…”

“…This allows for optoelectronic applications in the whole UV‐vis‐IR range by doping Ga 2 O 3 with optically active ions that present emission at the desired wavelength . In particular, our group has doped Ga 2 O 3 nanostructures with different elements, such as rare earths, transition metals, e.g., Cr 3+ or Mn, as well as isoelectronic dopants . With them, a wide range has been covered and interesting features for photonics, such as waveguiding and resonant cavity effects have been observed.…”

Reduced Graphene Oxide/InGaZn Mixed Oxide Nanocomposite Photocatalysts for Hydrogen Production

“…[58,59] The Ga 3d peak is observed at 20.4 eV, which shows the presence of Ga in the +3 oxidation state in 3RGO/IGZ. [60] The In 3d XPS spectrum shows two individual peaks at 444.6 and 452.1 eV assigned to In 3d 5/2 and In 3d 3/2 . These binding energies suggest the presence of In in the +3 oxidation state.…”

Antiferromagnetic superexchange interaction between Fe3+ ions in Fe3+ doped wide-gap oxide of β-Ga2−Fe O3 (x=0.1, 0.2, 0.3, 0.4)

“…The properties of β-Ga 2 O 3 , such as transportation [4][5][6][7][8][9], magnetism [10][11][12][13][14], and photoluminescence [15][16][17][18], can be greatly affected by the substitution of Ga 3 þ ions with the doped impurities. The previous investigations on the doping of β-Ga 2 O 3 indicate that compared with the Ga 3 þ ion ( $ 0.62 Å), the doped ion with a larger radius, such as Ti 4 þ [6], Cr 2 þ [19,20], Mn 2 þ [21,22], Fe 3 þ [23,24], In 3 þ [25,26], Er 3 þ [27], and Eu 3 þ [28], tends to occupy the B sites, while the doped ion with a smaller radius prefers to sit at the A site, such as Be 2 þ [26], and Si 4 þ [14].…”