Electron spin resonance measurements on (100)Si/SiOx/ZrO2 and (100)Si/Al2O3/ZrO2 stacks with nm-thick dielectric layers reveal, upon post-deposition oxidation in the range of 650 to 800C, the appearance of various SiO2-characteristic defects, including E’ and EX centers and a 95-G doublet. These defects generally grew during post-deposition oxidation treatment, attesting to significant modification of the SiOx interlayer, and/or additional SiOx interlayer growth. The electron spin resonance results on E’ indicated that the SiOx interlayer formed in (100)Si/SiOx/ZrO2 was drastically inferior to standard thermal (100)Si/SiO2, exhibiting over one order of magnitude more O-deficiency centers. The (100)Si/Al2O3 system appears more robust in terms of SiOx interlayer growth, and had better interlayer properties.

Paramagnetic Defects in Annealed Ultrathin Layers of SiOx, Al2O3 and ZrO2 on (100)Si. A.Stesmans, V.V.Afanasev: Applied Physics Letters, 2004, 85[17], 3792-4