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

Electrically detected magnetic resonance (EDMR), due to spin-dependent recombination (SDR), in commercial silicon p–n diodes is re-examined. New features were noted in our samples. The main signal, formerly seen as a single line and attributed to Pt dopant, occurred as three similar lines with g∥=2.028, 2.046, 2.073, and g⊥=1.969. EDMR centers aligned 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 seen in previous studies, but has passed unremarked. Though no favored explanations can be offered, these new complexities strongly suggest that extant theories of EDMR are incomplete.