Si-SiO2 interface passivation by plasma NH3 and atomic H

Plasma ammonia treatment at 400 °C leads to de-passivation of a fully hydrogenated Si-SiO2 interface, and to passivation of a fully de-hydrogenated Si-SiO2 interface. Plasma NH3 exposure causes irreversible Si surface damage and degradation of thermal stability. Atomic hydrogen exposure, although it results in similar effects on the Si-SiO2 interface, does not introduce additional defects or a decrease of the Si surface thermal stability. The difference between plasma NH3 exposure and atomic H exposure is speculated to be due to either the nitridation of Si-SiO2 interface or radiation damage resulting from plasma NH3 exposure. EPR measurements indicate changes of the paramagnetic defect properties and an increase in the paramagnetic defect density generated by plasma NH3 exposure.