Title :
First-principles analysis of precursor-surface reaction pathways relevant to plasma deposition of silicon thin films
Author :
Bakos, Tamas ; Maroudas, Dimitrios
Author_Institution :
Dept. of Chem. Eng., Univ. of Massachusetts, Amherst, MA, USA
fDate :
4/1/2005 12:00:00 AM
Abstract :
Passivation of silicon dangling bonds and abstraction of hydrogen by growth precursors are among the fundamental atomic-scale processes that determine the growth of hydrogenated amorphous silicon thin films during plasma-enhanced chemical vapor deposition from SiH4/H2 containing discharges. Using results of first-principles density functional theory calculations, combined with images of planar intersections of the three-dimensional valence electron density distribution, we determine the optimized reaction pathways and energetics of dangling bond passivation and hydrogen abstraction reactions. Both reactions are found to be barrierless and exothermic in accordance with the experimentally observed temperature-independent growth rate of amorphous Si thin films.
Keywords :
ab initio calculations; dangling bonds; density functional theory; elemental semiconductors; passivation; plasma CVD; plasma chemistry; semiconductor growth; semiconductor thin films; silicon; surface chemistry; valence bands; Si; atomic-scale processes; dangling bond passivation; discharges; exothermic reaction; first-principles density functional theory; hydrogen abstraction; hydrogenated amorphous silicon thin films; plasma deposition; plasma-enhanced chemical vapor deposition; precursor-surface reaction; three-dimensional valence electron density; Amorphous silicon; Atomic layer deposition; Chemical vapor deposition; Density functional theory; Hydrogen; Passivation; Plasma chemistry; Plasma density; Semiconductor thin films; Sputtering; Chemisorption; density functional theory; hydrogen abstraction; hydrogenated amorphous silicon thin films; plasma CD; surface reactions;
Journal_Title :
Plasma Science, IEEE Transactions on
DOI :
10.1109/TPS.2005.845002
