Hydrogen-induced thermal interface degradation in (111) Si/SiO2 revealed by electron-spin resonance

Electron-spin resonance (ESR) experiments show that the interface degradation induced in thermal (111) Si/SiO2 by postoxidation annealing (POA) in vacuum-previously isolated by ESR as a permanent creation of P-b (degrees Si equivalent to Si-3) interface defects-is strongly enhanced (similar to 6 times) when performed in H-2 ambient. It, thus, appears that the H-2 POA step, standardly applied to passivate interface states (preexisting P(b)s) naturally introduced during oxidation, effectively creates additional defect entities; the process initiates from similar to 550 degrees C onward vis-a-vis similar to 640 degrees C for vacuum. The results unveil the atomic nature of one of the mechanisms of the electrically long-known ii-induced POA generation of adverse interface states. (C) 1998 American Institute of Physics.