Characterization of the gate oxide thickness and the channel length dependencies of hot-carrier degradation in LDD p-MOSFETs

Abstract

The gate oxide thickness and the channel length dependencies of the hot-carrier induced degradation in buried-channel LDDp-MOSFETs are characterized for the first time. On one hand, the scaling of the channel length enhances the hot-carrier injection. On the other hand, a reduction in the gate oxide thickness improves the hot-carrier immunity. Our finding reveals that the scaling of the LDD p-MOSFETs does not necessarily lead to a reduction in the hot carrier hardness as long as a sufficiently thin gate oxide is utilized. A simple analytical model for the p-MOSFET degradation indicates that the improvement in the hot carrier hardness for the devices with thinner gate oxides may be attributed to the reduction in the total number of traps in the oxide.