Ring, chain, and cluster compounds in the Cl-Ga-N-H system

Area of Science:

• Computational Chemistry
• Materials Science
• Inorganic Chemistry

Background:

• Understanding gas-phase reactions is crucial for optimizing chemical vapor deposition (CVD) processes.
• Gallium Nitride (GaN) synthesis often involves complex precursor chemistries.
• Oligomerization of precursors can significantly impact deposition efficiency and material quality.

Purpose of the Study:

• To investigate the formation pathways of gas-phase oligomers in the Cl-Ga-N-H system.
• To evaluate the thermodynamic feasibility of various intermediates for Gallium Nitride (GaN) deposition.
• To compare the oligomerization behavior of Gallium-Nitrogen systems with Aluminum-Nitrogen systems.

Main Methods:

• Utilized hybrid Hartree-Fock/density functional theory (HF/DFT) for electronic structure calculations.
• Employed a polarized double-zeta quality basis set for high accuracy.
• Calculated geometric parameters, vibrational frequencies, and thermodynamic properties of key species.

Main Results:

• Characterized the Cl(3)GaNH(3) adduct, its dissociation products, amidochlorogallanes, and imidochlorogallanes.
• Predicted amidochlorogallane generation to be feasible during low-temperature laser-assisted CVD.
• Found high-temperature gas-phase association processes to be less important for GaN CVD compared to AlN CVD.

Conclusions:

• Amidochlorogallanes are promising intermediates for low-temperature GaN CVD.
• The reduced importance of high-temperature association for GaN is attributed to a weaker Ga-N bond energy compared to Al-N.
• This research provides insights into precursor design for efficient GaN synthesis.