Comparison of oxide leakage currents induced by ion implantation and high field electric stress

We compare in this work the electrical properties of gate leakage currents induced through the thin SiO2 oxide layer of metal-oxide-semiconductor stru ctures by high-energy ion implantation (Boron B2+) and high field electrica l stresses where electrons are injected from the gate in the Fowler-Nordhei m regime. Even if the high-frequency capacitance-voltage characteristics ar e very different after both treatments, comparable increases and similar sh apes are found at low field in static gate current-voltage curves, typical of equivalent oxide damage. Moreover, these stress or implantation induced leakage currents are both removed in a similar way by a thermal anneal unde r forming gas at 430 degreesC. We conclude that similar defects could be in duced through the oxide by both processes and generate those excess current s by a defect assisted tunneling mechanism. (C) 2001 Elsevier Science Ltd. All rights reserved.