Band gap engineering of N-alloyed Ga2O3 thin films

Abstract

The authors report the tuning of band gap of GaON ternary alloy in a wide range of 2.75 eV. The samples were prepared by a two-step nitridation method. First, the samples were deposited on 2-inch fused silica substrates by megnetron sputtering with NH3 and Ar gas for 60 minutes. Then they were annealed in NH3 ambience at different temperatures. The optical band gap energies are calculated from transmittance measurements. With the increase of nitridation temperature, the band gap gradually decreases from 4.8 eV to 2.05 eV. X-ray diffraction results indicate that as-deposited amorphous samples can crystallize into monoclinic and hexagonal structures after they were annealed in oxygen or ammonia ambience, respectively. The narrowing of the band gap is attributed to the enhanced repulsion of N2p -Ga3d orbits and formation of hexagonal structure.

Nano-engineering and functionalization of hybrid Au–MexOy–TiO2(Me = W, Ga) hetero-interfaces for optoelectronic receptors and nociceptors

“…The dissociation of the N 2 anion in the 2D Ga 2 O 3 film considerably altered its energy bandgap. The origin of the decreased bandgap is attributed to the N acceptor states [30][31][32] in the bandgap of Ga 2 O 3 . Therefore, N 2 -doped Ga 2 O 3 is considered a valuable candidate for tunable optoelectronic applications and can also affect the charge transfer mechanism at hetero-interfaces.…”

Zero-Power-Consumption Solar-Blind Photodetector Based on β-Ga2O3/NSTO Heterojunction

“…Current researches in solar-blind photodetectors focus mostly on wide bandgap semiconductors such as AlGaN, ZnMgO, diamond, and monoclinic gallium oxide (β-Ga 2 O 3 ). − However, there are obvious disadvantages in these structures, such as that the epitaxial quality of the AlGaN film deteriorates dramatically with increasing Al concentration, the single wurtzite phase of the MgZnO film breaks down with increasing Mg content, and the bandgap of diamond cannot be tuned. , β-Ga 2 O 3 is considered as an ideal candidate for its wide bandgap (4.9 eV), which lies sharply in the solar-blind spectrum region and also exhibits a flexible tunability in bandgap by alloying with different materials. Moreover, because of its high chemical and thermal stability, β-Ga 2 O 3 is favorable for robust devices that can work in harsh environments. − …”

Composition and Properties Control Growth of High-Quality GaOxNy Film by One-Step Plasma-Enhanced Atomic Layer Deposition

“…However, the method for fabricating the GaO x N y material is not mature. The only reported methods are chemical vapor deposition (CVD), oxidation or nitridation, , hydrothermal synthetic, and sol–gel spin coating technique . These methods have their own limitations: either the high deposition temperature (i.e., 800 °C in CVD process) is not suitable for semiconductor technology or the uncontrollable composition in the hydrothermal and nitridation process creates difficulties for precise performance tuning.…”