Effects of post-deposition annealing time in oxygen ambient on Y₂O₃ film deposited on silicon substrate

Abstract

In this work, systematic investigation was performed to study the effects of post-deposition annealing time (15, 30 and 45 minutes) at 1000°C in oxygen ambient on electrical characteristics of Y₂O₃ gate deposited on Si substrate using radio frequency magnetron sputtering. Capacitance–voltage characteristics of the investigated samples deduced the presence of positive-charged traps through the attainment of negative flatband voltage shift. Sample post-deposition annealing at 30 minutes demonstrated the lowest leakage current density and the highest breakdown voltage. This was owing to the acquisition of the lowest effective oxide charge, slow trap density, interface-trap density and total interface-trap density. It was determined that the leakage current of samples post-deposition annealing at 15 and 30 minutes is governed by Ohm's law, Mott–Gurney law and trap-filled-limit conduction. Only Ohm's law and trap-filled-limit conduction are dominating the leakage current of samples post-deposition annealing at 45 minutes.

Keywords:

• Oxygen
• Gate oxide
• Yttrium oxide
• Ohm's law
• Mott–Gurney
• Trap-filled-limit
• Space-charge-limited conduction

Acknowledgements

H.J.Q. would like to acknowledge Universiti Sains Malaysia, USM RU-PRGS (8044041) and Universiti Sains Malaysia Vice Chancellor's Award for their financial support.