Comparative analysis of the H-2 passivation of interface defects at the (100)Si/SiO2 interface using electron spin resonance

The passivation with molecular hydrogen in the range 213-234 degrees C of the interfacial P-b0 and P-b1 defects in (1 0 0)Si/SiO2, thermally grown at low temperature (<750 degrees C), has been analyzed by K-band electron spin resonance. The passivation kinetics are found to be well described by the same defect-H-2 reaction limited model applying to the interfacial P-b, defect (oSi=Si-3) in (1 1 1)Si/SiO2 grown at 850 degrees C. However, unlike P-b, that was typified by a single-valued activation energy for passivation E(a) = 1.66 eV, both P-b0 and P-b1 are found to exhibit a Gaussian spread sigma(Ea) similar to 0.15 eV around their respective mean E(a) values, deduced as 1.51 and 1.57 +/- 0.3 eV. The similar passivation kinetics are in line with assigning the P-b0 and P-b1 defects, like P-b, to an interfacial unpaired sp(3) Si hybrid. However, as there is no fundamental difference between P-b0 and P-b1 regarding passivation in H-2, more specific identification of P-b with either P-b0 Or P-b1, if any, cannot be concluded.