Electron spin resonance study of as-deposited and annealed (Hf O2) x (Si O2) 1-x high- κ dielectrics on Si

Abstract

Electron spin resonance measurements on 4 and 40 nm thick (Hf O2) 0.6 (Si O2) 0.4 and (Hf O2) 0.4 (Si O2) 0.6 high- κ films on (100)Si wafers detected Pb0 and Pb1 defects at the dielectric/Si interface and verified their identities with g value mapping. Annealings of a 4 nm thick (Hf O2) 0.6 (Si O2) 0.4 film in nitrogen at 800 and 1000 °C monotonically lowered total interface states. In contrast, the same annealings monotonically increased the total interface states observed in 40 nm thick films of both compositions. For the 4 nm technologically relevant thickness, the annealed (Hf O2) 0.6 (Si O2) 0.4 composition on (100)Si had lower interface states than the (Hf O2) 0.4 (Si O2) 0.6 composition on (100)Si. After nitrogen annealing at 800 °C, a third defect believed to be the EX, appears in larger quantities in the thicker 40 nm films. © 2007 American Institute of Physics.