Electrically detected magnetic resonance study of stress-induced leakage current in thin SiO2

A spin-dependent trap-assisted tunneling current has been detected in a thin (44.5 Å) SiO2 film. An electron paramagnetic resonance signal, obtained from the tunnel current, provides the first microscopic information regarding the identity of defects responsible for stress-induced leakage currents in thin SiO2. The observed electrically detected magnetic resonance spectrum is anisotropic and does not correspond to any of the commonly known defects in the Si/SiO2 system. The change in current is 2.4±0.3×10-7 at resonance, which we explain in terms of a spin-dependent hopping process. Assuming that the signal corresponds to traps in the oxide, we estimate sensitivity to ∼1×109 defects/cm2. © 1996 American Institute of Physics.