A pulsed EDMR study of charge trapping at Pb centers

Low temperature pulsed electrically detected magnetic resonance pEDMR measurements of charge trapping and recombination transitions involving Pb centers at the c Si 111 SiO2 inter face are presented. The results of these experiments show that when a conduction electron is trapped, it forms a strongly coupled spin pair with the defect electron prior to its readjustment into the charged Pb ground state. The data reveals that the Land factors of the two electrons within these pairs are almost identical difference lt; 0.002 and that they are, within the meas urement accuracy, identical to the Land factor of the uncharged, singly occupied Pb center. From this, it is concluded that trapping and recombination at Pb defects is dominated by direct charge capture and not by tunneling or hopping transitions from other localized states. Different cross sections attributed in previous studies to different interface defects at the c Si SiO2 interface can be explained by readjustment out of different spin configurations of the charged Pb defect