Effect of rapid thermal annealing on the electrical properties of ion‐beam‐synthesized oxide layers using 12 keV O2+ bombardment of Si

Abstract

AbstractSurface layers of SiO2 were synthesized by bombarding n‐type Si samples with 12 keV O2+ ions at 10° incidence in a SIMS instrument. The oxide layers were annealed at 950 °C for 3, 6 or 8.5 min under Ar flow in a rapid thermal annealer. Temperature‐dependent current–voltage (I–V–T) measurements were used in order to establish both the dielectric quality and the current transport mechanisms across the dielectric layers. Annealing for 8.5 min doubled the breakdown voltage while decreasing the leakage current by a factor of ∼18. The ohmic quality of the layers for the low field strengths decreased with the increasing annealing time, which is related to the removal of implantation damage as observed by high‐resolution RBS measurements. For the high field strengths, the tunnelling effect was most dominant for the oxide annealed for 8.5 min. The breakdown voltage of oxide layers exhibited an Arrhenius‐like dependence on the sample temperature, with the activation energy for breakdown decreasing with the increasing annealing time. Deep‐level transient spectroscopy (DLTS) and capacitance–voltage (C–V) measurements also were used to characterize the samples. Copyright © 2001 John Wiley & Sons, Ltd.