Journal of physics-condensed matter vol:13 issue:28 pages:L673-L680
Paramagnetic point defects were probed by electron spin resonance in stacks of (100) Si with mn-thin SiOx, ZrO2 and Al2O3 layers. After photodesorption of passivating hydrogen (300 K; 8.48 eV), the Si dangling bond type interface centres P-bo, P-b1 appear as prominent defects at all (100) Si/dielectric interfaces, with P-bo densities up to similar to6 x 10(12) cm(-2). This P-bo, P-b1 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. As probed by the P-b-type defects, the interfaces are under substantially enhanced stress, characteristic for low-temperature Si/SiO2 growth. Standard quality thermal Si/SiO2 interface properties, as exposed by the P-b-type defects (density similar to 1 x 10(12) cm(-2)), may be approached by appropriate mild annealing (similar to 650 degreesC). This fact of a naturally present or possibility to establish a high quality (100) Si/SiO2-type interface, with ultrathin SiO2 interlayer, may be basic to successful application of high-kappa metal oxides in Si-based devices.