Room-temperature conductivity and location of mobile sodium ions in the thermal silicon dioxide layer of a metal-silicon dioxide-silicon structure

Room-temperature conductivity of mobile Na+ ions in the SiO 2 layer of a metal-silicon dioxide-silicon structure is directly shown to be interface limited by use of the photo I-V technique. Na+ ions were found to be located within ≈50 Å of the interfaces regardless of field stressing conditions (2-4.5 MV/cm), temperature (20-40°C), number of ions drifted (up to 2.6×1012 cm-2), or number of temperature-bias cycles used to move Na+ ions back and forth between the interfaces.