Lateral Nonuniformity of the Tunneling Current of Al/SiO2/p-Si Capacitor in Inversion Region Due to Edge Fringing Field Effect

Abstract

Interesting area and perimeter dependency mechanisms of dark gate current in Al/SiO2/p-Si capacitor is demonstrated. To study this lateral non-uniformity phenomenon, three different thicknesses of top aluminum gate are intentionally designed to our capacitors. According to C-V and I-V measurements carried out in the dark, it is found that the device with thin top Al-gate will result in entirely different electrical characteristics compared with the device with thick top Al-gate. Moreover, measurements with light illumination show that there is enhanced edge charge collection efficiency in inversion due to edge fringing field effect.