SIMOX with epitaxial silicon: point defects and positive charge

Electron paramagnetic resonance (EPR), capacitance-voltage (CV) and point contact transistor measurements are used to investigate the radiation response of the SIMOX substrate emphasizing the difference between those samples with and without an epitaxial Si layer. It is shown that the hydrogen present during epitaxial deposition is responsible for a tenfold increase in radiation induced defects. Furthermore, the measurements indicate that the density of positive charge and oxygen vacancy related defects (E' centers) typically associated with this charge are not correlated in the case of hydrogen treated buried oxides. A model for E' generation in epitaxial SIMOX will be developed based on the known influence of hydrogen and lack of positive charge creation. Results of etch back measurements are briefly addressed.>