Fundamental differences in the nature of electrically active point-defects in plasma enhanced chemical vapor deposited and thermal oxide structures

We have investigated plasma enhanced chemical vapor deposited (PECVD) and thermal oxides using electron spin resonance (ESR). We have been able to show that electron injection into PECVD oxides results in the generation of neutral E′ centers. The E′ center is an unpaired electron on a silicon backbonded to three oxygens. However, in thermal oxides, E′ centers are generated by hole injection, not electron injection; thermal oxide E′ centers are positively charged. Thus, there are fundamental differences in the point-defects in thermally grown and PECVD oxides.