Abstract
This paper studies the adverse environmental impacts of atomic layer deposition (ALD)
nano-manufacturing technology on ALD of Al2O3 nano-scale thin films. Numerical
simulations with detailed ALD surface reaction mechanism developed based on Density
Functional Theory (DFT), and atomic-level calculations are performed to investigate the
effects of four process parameters including process temperature, pulse time, purge time, and
carrier gas flow rate on ALD film deposition rate, process emissions and wastes. Full-cycle
ALD simulations reveal that the depositions of nano-thin-films in ALD are in essence the
chemisorption of the gaseous species and the conversion of surface species. Methane
emissions are positively proportional to the film deposition process. The studies show that
process temperature fundamentally affects the ALD chemical process by changing the energy
states of the surface species. Pulse time is directly related to the precursor dosage. Purge time
influences the ALD process by changing the gas-surface interaction time, and higher carrier
gas flow rate alters the ALD flow field by accelerating the convective heat and mass transfer
in ALD process.