Transit times of SiGe:C HBTs using non selective base epitaxy

Abstract

The transit times of SiGe:C HBTs using a non selective base epitaxy are investigated at 300 K and low temperature. The transit times depending on base boron dose and activation anneal conditions are investigated. Because the current gain strongly increases at low temperature, we can analyze dynamic performances versus temperature. We separate every charging and transit times over the temperature, in order to provide a better understanding of the 300 K behavior and to open up the road to further frequency optimization.