Electron spin resonance analysis of interfacial Si dangling bond defects in stacks of ultrathin SiO2, Al2O3, and ZrO2 layers on [formula omitted]Si

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Paramagnetic point defects were probed by electron spin resonance in stacks of (100)Si with nm-thin SiOx, ZrO2, and Al2O3 layers. After hydrogen photodesorption (8.48 eV; 300 K), the Si dangling bond interface centers Pb0, Pb1 appear as prominent defects at all (100)Si/dielectric interfaces. This Pb0, Pb1 fingerprint, generally unique for the thermal (100)Si/SiO2 interface, indicates that, while reassuring for the Si/SiOx/ZrO2 case, the as-deposited (100)Si/Al2O3 interface is basically Si/SiO2-like. The interfaces are under enhanced stress, typical for low temperature Si/SiO2 growth. Standard quality thermal Si/SiO2 interface properties, as exposed by the Pb-type defects (density ∼1×1012 cm−2), may be approached by appropriate annealing (∼650 °C). A high quality (100)Si/SiO2 type interface, with ultrathin SiO2 interlayer, may be basic to successful application of high-κ metal oxides in Si-based devices.