Structural and Dynamic Properties of Gallium Alkoxides.

Area of Science:

• Inorganic Chemistry
• Materials Science
• Nanotechnology

Background:

• Gallium oxide (Ga2O3) is a promising semiconductor material with applications in electronics and optoelectronics.
• Developing efficient and reliable precursors for Ga2O3 thin film deposition is crucial for its technological advancement.
• Aerosol-assisted chemical vapor deposition (AACVD) offers a versatile route for thin film fabrication.

Purpose of the Study:

• To synthesize and characterize novel chlorido-gallium alkoxide precursors.
• To investigate the solution behavior and fluxional properties of these precursors using variable-temperature nuclear magnetic resonance (VT-NMR) spectroscopy.
• To evaluate the efficacy of these precursors for the deposition of gallium oxide thin films via AACVD.

Main Methods:

• Synthesis of gallium alkoxide complexes via salt metathesis and ligand exchange reactions.
• Structural characterization using mass spectrometry and VT-NMR spectroscopy.
• Computational analysis using density functional theory (DFT) to understand ligand coordination.
• Thin film deposition using AACVD followed by annealing.
• Film characterization using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV-visible spectroscopy, and energy dispersive X-ray analysis (EDX).

Main Results:

• Successful synthesis of oligomeric and monomeric chlorido-gallium alkoxide precursors.
• VT-NMR and DFT studies revealed hemilabile coordination of the alkoxide ligands.
• AACVD deposition at 450 °C yielded amorphous Ga2O3 films.
• Annealing at 1000 °C converted amorphous films to crystalline Ga2O3.

Conclusions:

• Chlorido-gallium alkoxides with hemilabile ligands are effective precursors for AACVD.
• The synthesized precursors enable the formation of Ga2O3 thin films.
• The process allows for the transformation of amorphous to crystalline Ga2O3, suitable for various applications.