Improvement of hot carrier lifetime by cleaning process prior to selective reoxidation in metal gate LDD nMOSFETs

Abstract

We have investigated the effects of the cleaning process prior to selective reoxidation on the device reliability against hot carrier degradation. A remarkable increase in the lifetimes was obtained for the devices in which the remaining oxide under the LDD spacer was partially removed. This additional cleaning process was found to effectively improve the interface quality of the spacer bottom oxide.