New features of electrically detected magnetic resonance in silicon p-n diodes

Electrically detected magnetic resonance (EDMR), due to spin-dependent reco mbination (SDR), in commercial silicon p-n diodes is re-examined. New featu res were noted in our samples. The main signal, formerly seen as a single l ine and attributed to Pt dopant, occurred as three similar lines with g(//) = 2.028, 2.046, 2.073, and g(perpendicular to) = 1.969. EDMR centers align ed in only one direction were seen: with g(//) along the diode axis, which is also a Si[111] bond direction. This restricted directionality may be see n in previous studies, but has passed unremarked. Though no favored explana tions can be offered, these new complexities strongly suggest that extant t heories of EDMR are incomplete. (C) 2000 Published by Elsevier Science Ltd.