Comparison of DC/AC Hot Carrier Degradation between Short Channel Si Bulk and SiGe SOI p-FinFETs

Abstract

In this study, both direct current (DC) and alternating current (AC) hot carrier degradation (HCD) of Si Bulk p-FinFETs and SiGe SOI p-FinFETs with 40 nm channel length are compared. The time exponent (n), activation energy (E-A) and voltage acceleration factor (VAF) under different HCD stress conditions are investigated. Experiments show that DC HCD of Si FinFETs is almost 1.2 times of that of SiGe FinFETs at room temperature. However, SiGe SOI FinFETs are more sensitive to AC signal frequency than Si Bulk FinFETs in AC HCD measurement. With AC frequency increasing, oxide traps capture in AC HCD of SiGe FinFETs is becoming dominant due to the reduction of slow-interface traps capture.