Electrically active interface defects in Si/SiO₂ and Si(100)/HfO₂ structures

This paper provides an overview of the energy distribution of electrically active interface states in Si/SiO₂ and Si/HfO₂ structures, based on analysis of the capacitance-voltage (CV) and conductance-voltage (GV) characteristics. For the Si/SiO₂ system, results are presented on the energy distribution of interface states following rapid thermal annealing (RTA) in an N₂ ambient for the thermally oxidized Si(100), Si(110) and Si(111) orientations. An examination of the interface states from CV analysis combined with electron spin resonance (ESR), demonstrates hydrogen dissociation from P_b0/P_b1) dangling bond centres resulting from the RTA step. The energy distribution of interface states for Si(100)/HfO₂ structures are presented and compared to the hydrogen free Si(100)/SiO ₂ interface. Analysis of the interface state distribution and density from CV, GV and ESR, provides evidence that the frequency dependant features commonly observed in the CV response of Si(100)/HfO₂ structures are due to PW dangling bond centres.