Observations were made, using electron spin resonance, of P-related point defects in nm-thick HfO2 films on (100)Si after annealing at 500 to 900C and in ZrO2 powder. Based upon the principal g-matrices and hyperfine tensors deduced from consistent X-, K-, and Q-band spectra simulations and comparison with established P-associated defects in silica, both centers appeared similar in nature and were attributed to a P2-type defect; P replacing a Hf or Zr atom. Both centers were observed in the monoclinic phase of the high-κ oxides, with the unpaired electron strongly localized on the P atom. Within the concern about dopant penetration out of Si into the high-κ layers on top, identification of the dopant-associated defects in the latter appears crucial to which the present basic results provide fundamental access. The centers may operate as detrimental charge trapping sites.

P-Associated Defects in the High-κ Insulators HfO2 and ZrO2 Revealed by Electron Spin Resonance. A.Stesmans, K.Clémer, V.V.Afanasev: Physical Review B, 2008, 77[12], 125341 (9pp)