Density of states of Pb1 Si/SiO2 interface trap centers

The electronic properties of the (100) Si/SiO2 interfacial defect called Pb1 are quite controversial. We present electron spin resonance measurements that demonstrate: (1) that the Pb1 defects have levels in the silicon band gap, (2) that the Pb1 correlation energy is significantly smaller than that of the Pb1 defect, and (3) that the Pb1 levels are skewed toward the lower part of the silicon band gap.