X-ray CTR Measurements of Oxidation Reaction at the interface of HfSiO_x/SiO₂/Si structures

Abstract

X–ray crystal truncation rod (CTR) scattering was applied to the measurement of oxidation reaction at the SiO₂/Si interface under high–permittivity (high–k) materials. Effects of the nitridation process and thermal annealing on the interface structure were investigated by monitoring the CTR intensity. We found that oxidation reaction at the interface has progressed during thermal annealing for HfO₂/SiO₂/Si and HfSiOx/HfO₂/Si structures. Oxidation reaction has also progressed during the nitridation process and post–deposition annealing (PDA). However, the CTR intensity did not change during the thermal annealing for the nitrided sample, indicating the suppression effect of the nitridation on the oxidation reaction.