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Fabrication and Operation of an Oxygen Insert for Adherent Cellular Cultures
Published on: January 6, 2010
Inward diffusion of oxygen on a silicon surface
1Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
Physical Review Letters
|September 16, 2000
Summary
Density functional theory computations reveal that oxygen diffusion into silicon substrates is facilitated by surface dangling bonds. This process has a low activation energy, suggesting efficient oxygen incorporation into silicon.
Area of Science:
- Surface Science
- Computational Materials Science
- Solid-State Chemistry
Background:
- Understanding oxygen diffusion on silicon surfaces is crucial for semiconductor manufacturing.
- Previous studies have explored oxygen interactions with silicon, but detailed mechanisms remain under investigation.
Purpose of the Study:
- To elucidate the diffusion mechanism of oxygen atoms adsorbed on a silicon surface.
- To quantify the activation energy for inward oxygen diffusion into the silicon substrate.
Main Methods:
- Density functional theory (DFT) cluster computations were employed.
- Calculations focused on modeling oxygen atom adsorption and diffusion on a silicon surface.
Main Results:
- The activation energy for oxygen diffusion into the silicon substrate was calculated to be 1.6 eV.
- A significant reduction in activation energy was observed due to the presence of surface dangling bonds.
- An intermediate species facilitating Si-O bond rearrangement was identified.
- Enhanced inward diffusion was noted with the adsorption of a second oxygen atom.
Conclusions:
- Surface dangling bonds play a critical role in lowering the activation energy for oxygen diffusion into silicon.
- The findings provide insights into the initial stages of silicon oxidation and oxygen incorporation.
- Further adsorption of oxygen can accelerate the diffusion process.
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