Atomistic Simulations of Plasma-Enhanced Atomic Layer Deposition

Area of Science:

• Materials Science
• Chemical Engineering
• Computational Chemistry

Background:

• Plasma-enhanced atomic layer deposition (PEALD) is a critical technique for thin-film fabrication.
• Accurate atomistic simulations are needed to understand and optimize PEALD processes.
• Existing models often lack realistic precursor representations.

Purpose of the Study:

• To develop and validate an atomistic simulation scheme for PEALD.
• To investigate the influence of precursor-surface interactions on SiO2 thin film growth.
• To identify key parameters for achieving dense SiO2 films with minimal impurities.

Main Methods:

• Combined Monte Carlo deposition algorithm with molecular dynamics for structure relaxation.
• Utilized a realistic, atomistic precursor model to account for steric and overlap effects.
• Incorporated process parameters as probabilities for precursor product formation at each step.

Main Results:

• Simulations revealed that precursor binding to single surface oxygen atoms promotes amorphous growth, high -OH content, and voids.
• Increased binding to two surface oxygen atoms resulted in dense SiO2 films and reduced -OH impurities.
• Optimizing precursor site formation probabilities is crucial for film quality.

Conclusions:

• The developed atomistic simulation accurately models PEALD processes.
• Controlling precursor binding modes is essential for tailoring SiO2 thin film properties.
• This approach provides a pathway for designing high-quality PEALD-grown films.