Reaction mechanism of N atoms interaction with low-k organosilicate glass films: Dynamic density functional theory study

Damage of porous organosilicate glass films with low dielectric constants (low-k films) in plasma processing is a critical problem for modern microelectronics. For this problem, understanding and revealing of basic reactions for radical (e.g., O, F, and N atoms) interactions with low-k films are of importance. In this study, reactions of initial (Si‒CH3) and appeared (Si‒CHxNy) surface groups with incident N atoms in the ground and excited metastable states were simulated systematically by the dynamic density functional theory (DFT) method. On the basis of a large amount of calculated vibrational modes of various N-containing groups and reaction trajectories, the most important Si‒CHxNy groups for the explanation of obtained experimental data were selected and the most probable reaction pathways were found and described in detail. The proposed reaction mechanism revealed by DFT modeling is used to analyze and to explain the measured FTIR spectra changes with N atom doses and temperatures of porous low-k films.Damage of porous organosilicate glass films with low dielectric constants (low-k films) in plasma processing is a critical problem for modern microelectronics. For this problem, understanding and revealing of basic reactions for radical (e.g., O, F, and N atoms) interactions with low-k films are of importance. In this study, reactions of initial (Si‒CH3) and appeared (Si‒CHxNy) surface groups with incident N atoms in the ground and excited metastable states were simulated systematically by the dynamic density functional theory (DFT) method. On the basis of a large amount of calculated vibrational modes of various N-containing groups and reaction trajectories, the most important Si‒CHxNy groups for the explanation of obtained experimental data were selected and the most probable reaction pathways were found and described in detail. The proposed reaction mechanism revealed by DFT modeling is used to analyze and to explain the measured FTIR spectra changes with N atom doses and temperatures of porous low-k f...