| Abstract |
The quality of epitaxial silicon layers grown on Czochralski single crystal substrates directly influences device parameters and yield. Unintentional doping of these layers from the substrate has been well studied. However we found no reports on unintentional oxygen contamination of epilayers due to its presence in the substrate. The use of high spatial resolution Fourier transform infrared spectroscopy in transversal mode is shown to be a powerful technique for both oxygen profiling and precipitation studies. A significant difference in oxygen behaviour during the epitaxial layer growth, even for lightly P doped substrates, is found. Oxygen, that in some cases diffuses significantly into the grown epitaxial layer, tends to form precipitates there. This is an important consequence of outdiffusion, since it directly influences the quality of the epitaxial layer. |
