Electron spin resonance observation of Si dangling-bond-type defects at the interface of (100) Si with ultrathin layers of SiOx, Al2O3 and ZrO2

Paramagnetic point defects were probed by electron spin resonance in stacks of (100) Si with mn-thin SiOx, ZrO2 and Al2O3 layers. After photodesorptio n of passivating hydrogen (300 K; 8.48 eV), the Si dangling bond type inter face centres P-bo, P-b1 appear as prominent defects at all (100) Si/dielect ric 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 int erface, 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 t he P-b-type defects, the interfaces are under substantially enhanced stress , characteristic for low-temperature Si/SiO2 growth. Standard quality therm al Si/SiO2 interface properties, as exposed by the P-b-type defects (densit y similar to 1 x 10(12) cm(-2)), may be approached by appropriate mild anne aling (similar to 650 degreesC). This fact of a naturally present or possib ility to establish a high quality (100) Si/SiO2-type interface, with ultrat hin SiO2 interlayer, may be basic to successful application of high-kappa m etal oxides in Si-based devices.